Dopamine receptor sites in the anterior pituitary.

An immunocytochemical method was developed to visualize dopamine receptor sites on dispersed anterior pituitary cells of the rat. Dopamine receptors were labeled with the antagonist haloperidol. Some cells were incubated with haloperidol and a 100-fold excess of the potent antagonist D-butaclamol to determine nonspecific binding. The labeled sites were stained with an antibody against haloperidol and the peroxidase anti-peroxidase (PAP) technique. PAP complexes which served as markers for dopamine binding sites appeared on the outer plasmalemmal surface of the vast majority of mammotrophs. PAP complexes attached to the inner surface of endocytotic vesicle membrane suggested internalization of receptor-rich portions of the plasmalemma. Some gonadotrophs and somatotrophs were specifically stained to a lesser extent. However, high receptor site density and internalization of PAP complexes were never observed on cell types other than mammotrophs. The presence of dopamine receptors on the plasmalemma of mammotrophs provides strong additional evidence that dopamine acts upon these cells as a prolactin inhibitory hormone.


Identification of immunoreactive sites in bovine parathyroid cells to antibodies raised against the NH2-terminal sequence of parathyroid hormone.

The NH2-terminal sequence of bovine parathyroid hormone (1-84) was localized with different immunocytochemical methods on the light and electron microscopic level in bovine parathyroid glands and in isolated bovine parathyroid parenchymal cells. The peroxidase labeled staphylococcal protein A and the peroxidase anti-peroxidase method were found to be advantageous for light and electron microscopic localization, respectively. Reaction product was found light microscopically in the cytoplasma of the parenchymal cells and electron microscopically largely over the secretion granules of the parenchymal cells. The immunoreactive sites were subsequently identified to represent only intact parathyroid hormone (1-84) by gel electrophoresis derived enzyme linked immunosorbent assay.


A quantitative immunoperoxidase procedure employing energy dispersive x-ray analysis.

A method is described for substituting gold for osmium as a marker in the unlabeled antibody technique. The gold marker can be detected in the light or electron microscope. The gold-labeled reaction product can be detected in lower concentrations than osmium and can be used as the basis for quantitating antigen concentrations in cells and tissues with the scanning electron microscope and energy dispersive x-ray analysis.


Immunocytochemical studies of the evolution of islet hormones.

By using both immunofluorescence and peroxidase-anti-peroxidase procedures to detect cells producing the four islet hormones, supplemented by biochemical, biological, and radioimmunological assays of tissue extracts, it has been shown that insulin seems to be the most original hormone, apparently occurring already in invertebrates in cells of open type in the alimentary tract mucosa. Insulin cells also predominate in the first islet organ, namely that of the cyclostomes. The order of appearance in the endocrine pancreas during the subsequent evolution is: somatostatin; glucagon; and the pancreatic polypeptide. Even in lower vertebrates pancreatic polypeptide cells occur in those parts of the pancreas situated in close proximity to the gut.


The rise and fall of the baby's bottle.

As the traditional practice of breast-feeding and later weaning of babies slowly regains popularity in Europe and America, the Third World is just getting used to the idea of bottle-feeding and early weaning. Infant food manufacturers have been indicted for irresponsible marketing of their products, but they are not totally responsible for the present situation. The author examines the origins and development of bottle-feeding, and argues that the present polarisation of views can only be resolved by cooperation between the antagonists.


Delayed advent of stringent, non-H-2 genetic regulation of the antibody response to a protein antigen.

The role of non-H-2 gene(s) in the control of the antibody response to three lysozymes was investigated. Upon secondary challenge, A/J (H-2a) mice generated at least a 25-fold greater anti-lysozyme plaque-forming cell response than did B10.A (H-2a) mice. Nearly equal, strong peak primary responses, predominantly IgG in nature, were obtained from both A/J and B10.A mice after a single challenge with lysozyme in complete Freund's adjuvant. However, clear differences in responses are seen within 5 days after the peak primary plaque-forming response and by day 28 at the serum antibody level. B10.A mice never equal their primary responses, whereas A/J mice demonstrate positive immune memory. It appears that a non-H-2 gene(s) that regulates the overall antibody level to a protein antigen becomes manifest only after an initial antibody response.


Sensitivity of long-standing xenografts of rat hearts to humoral antibodies.

Long-standing rat skin xenografts on immunosuppressed mice are known to become insensitive to destruction by mouse anti-rat serum. Our present experiments demonstrate that long-standing primarily vascularized rat-to-mouse cardiac xenografts, unlike skin, remain fully sensitive to antiserum-mediated destruction, even in mice also bearing a long-standing skin graft that is resistant to antiserum. It appears that skin grafts become resistant to antiserum-mediated destruction because of extensive replacement of the endothelium by cells of host origin. The hearts remain sensitive to antiserum since such an extensive endothelial replacement would not occur as readily in these whole organ grafts.


Tissue distribution of immunoglobulin-secreting cells in normal and IgA-deficient chickens.

A reverse hemolytic plaque assay was employed to enumerate lymphoid cells actively secreting either immunoglobulin (Ig)G, IgA, or IgM in the small intestine, lungs, and lymphoid organs of normal and IgA-deficient chickens. In normal birds, intestinal lamina propria lymphocytes were proportionately richest in cells secreting IgG and IgA whereas the bone marrow was richest in IgM-secreting cells. The highest ratio of IgA to IgG secreting cells was also found in the lamina propria lymphocytes of the intestine (0.9), followed by the IgA to IgG ratios in the intestinal epithelium (0.31), and the lungs (0.19). The IgA to IgG ratios in the bone marrow (0.08) and the spleen (0.02) were considerably lower. Thus, both the intestine and the lungs were relatively enriched in cells actively secreting IgA. These IgA-secreting cells are the likely source of the IgA found in such quantities in intestinal and respiratory secretions. The tissue distribution of Ig-secreting cells was also studied in two generations of birds with experimentally induced IgA deficiency. There was a striking diminution of IgA-secreting cells in all tissues, including the intestine and lungs, whereas cells secreting IgG and IgM were normal or increased. The lack of IgA-secreting cells in these birds represents the effects of donor suppressor T cells having specificity for IgA.


An enzyme immunoassay (EIA) for progesterone in horse plasma.

A simple enzyme immunoassay (EIA) for the measurement of progesterone is described. Antibody against 11-OH-hemisuccinate-BSA is bound to polystyrene tubes. 11-OH-hemisuccinyl-beta-D-galactosidase is used as enzyme-coupled antigen and methylumbelliferyl-beta-D-galactoside as substrate. Concentrations down to 0.156 ng/ml plasm or amounts of 93 pg/tube are detectable. Probit analysis gave a linear relationship between log concentration and percentage of binding. A comparison of EIA and radioimmunoassay gave a correlation coefficient of 0.81. The assay is sufficiently sensitive to estimate progesterone levels in plasma.


An alternative method of expressing results of lymphocyte transformation experiments.

The use of counts per minute, disintegrations per minute and stimulated index as a means of expressing lymphocyte transformation is discussed. An alternative method is proposed, namely, that the degree of transformation is more effectively measured by the difference in incorporation of nucleoprotein base by stimulated as compared with unstimulated cultures expressed in moles uptake of base per unit number of lymphocytes.


In vitro induction of cytotoxic effector cells against human neoplasms. I. Sensitization conditions and effect of cryopreservation on the induction and expression of cytotoxic responses to allogeneic leukemia cells.

Peripheral blood lymphocytes (PBL) from normal human donors were sensitized in vitro against allogeneic human acute myelocytic leukemia (AML) cells by means of an unidirectional mixed lymphocyte-tumor cell culture (MLTC) technique. The cytotoxic responsiveness of the sensitized lymphocytes, as determined in vitro by the 51Cr-release assay, varied among individual lymphocyte donors and was greatly dependent on the sensitization culture conditions. Induction of cytotoxic effector cells was augmented appreciably by adding to the cultures minute amounts of the immunopotentiating agent MER-BCG. Responding lymphocytes and stimulating leukemia cells cryopreserved for several weeks in liquid nitrogen were as effective as fresh cells in generating effector lymphocytes; the cytotoxic capacity of already sensitized lymphocytes was fully retained by cryopreservation. The implications of these findings for possible clinical employment of in vitro sensitized lymphocytes in adoptive immunotherapy of cancer are discussed.


Lymphocyte cultures with small numbers of cells.

Prior experience with cultures of cerebrospinal fluid lymphocytes indicated a need to develop methods for culturing small numbers of cells. Peripheral blood lymphocytes (PBL) were obtained from 20 normal volunteers. Standard microcultures using 100 X 10(3) PBL/0.2 ml and cultures with 50, 25 and 12.5 X 10(3) in 0.1 ml or 0.2 ml were established in RPMI 1640 with autologous plasma. These cultures were incubated with PHA (1--30 microgram) for 3, 4 and 5 days, pulsed with [3H]thymidine and harvested. In unstimulated cultures, cpm declined linearly with decreasing cell numbers. Standard cultures (100 X 10(3) PBL/0.2 ml) had maximal PHA stimulation (80,916 +/- 6394) at day 3 with 30 microgram PHA. Other 0.2 ml cultures had lower cpm. By culturing 25 X 10(3) PBL in 0.1 ml for 3 days cpm were 82,874 +/- 6875 with 30 microgram PHA and 77,153 +/- 6022 with 15 microgram PHA and were similar to standard cultures. Similar cpm were seen with 12.5 X 10(3) PBL in 0.1 ml after 4 days with 30 micrograms of PHA (80,838 +/- 6674) and with 15 micrograms of PHA (72,860 +/- 6243), and also after 5 days with 30 micrograms of PHA (86,703 +/- 6732) and with 15 micrograms of PHA (74,066 +/- 6388). The maximal response (126,578 +/- 6580) was seen with 25 X 10(3) PBL/0.1 ml at day 4 with 30 micrograms of PHA. By decreasing culture volume to 0.1 ml and increasing time, the number of cells necessary to give PHA responses similar to standard cultures can be reduced by 75--88%.


The H-2 histocompatibility system and lymphocyte adhesion: interaction modulation factor involvement.

The effects of thymocyte interaction modulation factor on the adhesion of mouse allogeneic thymocytes and B-cells are reported. This glycoprotein, produced by short term cultures of thymocytes, has already been described as reducing the adhesion of syngeneic B-cells, leucocytes and macrophages. Adhesion was measured in suspension culture using the collision efficiency method. This paper reports that: 1. In addition to the syngeneic effect of thymocyte IMF in reducing adhesion of certain unlike cell types there is also an allogeneic effect in which an allogeneic T-IMF will diminish the adhesion of a thymocyte population, or still further reduce the adhesion of a B-cell population than would a syngeneic T-IMF. 2. Thymocyte IMFs were prepared from different congenic strains and tested on the adhesion of syngeneic and allogeneic thymocytes. When factor and cells were syngeneic or matched at any H-2 locus except H-2 D there was no effect on adhesion since it remained at the same value as in controls in their own IMF. But whenever factor and cells were mismatched at H-2 D there was a marked diminution in the adhesion of the cells. 3. Antibodies raised against specific thymocyte IMFs could be used to detect the presence of T-IMF binding to the surface of cells by immunofluorescence or immune cytolysis. These systems show that the antibodies against thymocyte IMF can be used to type the H-2 D type of a cell and that these factors are present at the surface of thymocytes and certain other cell types. They confirm that the thymocyte IMF is either in H-2 D product or is closely associated with H-2 D locus in its binding and action. They also show that the T-IMF antigen on non-lymphocytic types is produced by T-cells or thymocytes. 4. The general relevance of these results is discussed in relation to cell recognition phenomena.


Ro 20-1724: an agent that significantly improves psoriatic lesions in double-blind clinical trials.

Two double-blind studies comparing the effectiveness of the cyclic nucleotide-altering agent (4-[3-butoxy-4-methoxybenzyl]-2-imidazolidinone) (Ro 20-1724) vs vehicle have demonstrated that this compound can improve psoriatic lesions. Although Ro 20-1724 was not as effective as intensive occlusive treatment of psoriatic lesions with 0.025% triamcinolone acetonide, Ro 20-1724 had no adverse systemic or cutaneous effects. Ro 20-1724 and other cyclic nucleotide-altering agents may have therapeutic potential in the future treatment of psoriasis.


Purification of a mannan from Candida albicans which activates serum complement.

Candida species activate complement by the alternative pathway, induce leukocyte migration and, when applied epicutaneously, cause epidermal microabscesses of neutrophils in man and experimental animals. Complement activation by C. albicans appears to be a property of the cell wall. To biochemically identify the complement-activating constituent(s) of C. albicans, an ethyleneglycol extract of growth phase blastospores was prepared. Acid hydrolysis and neutral sugar analysis revealed mannose (82%), fucose (7%), and glucose (11%). The soluble, mannose-rich cell wall polysaccharide of C. albicans activates serum complement via the alternative pathway, induces neutrophil chemotaxis and is antigenically reactive with antisera to C. albicans. This constituent exhibits in vitro endotoxin-like activity as measured by Limulus lysate gelation, but is nonpyrogenic in rabbits. The extracts produced precipitin lines in double immunodiffusion studies against serum from patients with invasive candidiasis and rabbit antisera to mycelial and blastospore preparations of C. albicans, but not against normal serum. Thus, pathogenic properties and reactive phenomenon of C. albicans are in part attributable to a cell wall polysaccharide, mannan.


Sebaceous gland differentiation: II. The isolation, separation and characterization of cells from the mouse preputial gland.

Viable cells have been isolated, by enzyme digestion, from mouse preputial glands and have been separated, by isopycnic centrifugation, into populations of different buoyant densities. The separated cells have been evaluated by morphological and biochemical criteria to assess the success of the separation procedure in terms of the stage of differentiation of each cell population. Use of Ficoll as gradient medium for the isopycnic centrifugation proved unsuccessful, but good separations were obtained when Metrizamide was used. The separated cells from the Metrizamide gradient were shown to be in different stages of differentiation. Techniques are described for the special handling of these cells as well as suitable assay procedures. Some of the properties of the separated cells are described.


Susceptibility of Escherichia coli K1 to four combinations of antimicrobial agents potentially useful for treatment of neonatal meningitis.

The synergy of four combinations of antimicrobial agents potentially useful in the treatment of neonatal meningitis was examined with 19 strains of Escherichia coli K1. The effect on antimicrobial activity of changes in E. coli concentration and in pH to values similar to those of cerebrospinal fluid from infected neonates was also assessed. The degree of synergy, assessed by checkerboard agar dilution of the antimicrobial agents in combination with gentamicin, decreased in the following order: trimethoprim, cefamandole, ampicillin, and chloramphenicol. Significant variation in activity against different strains of E. coli was not observed. In broth dilution tests, the individual antimicrobial agents, but not the combinations, were notably less active at pH 7.00 with an inoculum of 10(7) cfu/ml than at pH 7.40 with 10(5) cfu/ml. Bactericidal activities of the beta-lactam and trimethoprim combinations were similar. Chloramphenicol antagonized the bactericidal effect of gentamicin and of ampicillin plus gentamicin.


Treatment of experimental nocardiosis in mice: comparison of amikacin and sulfonamide.

Recent in vitro susceptibility studies have shown that amikacin inhibits more than 90% of isolates of Nocardia. This study was designed to evaluate the effect of treatment with amikacin or sulfonamides on infection caused by Nocardia asteroides with the use of murine models. In an acute lethality model in which infection was induced by intraperitoneal injection, 13 (45%) of 29 mice that had been treated with amikacin survived, in comparison to zero of 39 untreated animals in the control group and one of 39 mice that had been treated with sulfadiazine (P less than 0.001 for amikacin). When infected with a strain of N. asteroides that was resistant to amikacin, all mice that were treated with amikacin and all untreated mice died. Drug therapy was also evaluated in a chronic infection model, in which abscesses were produced by an intraperitoneal injection of N. asteroides in saline. Treatment with either amikacin (P less than 0.001) or sulfonamide (P less than 0.02) for two to three weeks significantly increased the rate of resolution of these abscesses. These murine models demonstrate that amikacin has in vivo activity against Nocardia and may be potentially useful in the treatment of human disease.


Effects of glucose and amino acids on insulin, glucagon and zymogen granule size of foetal rat pancreas grown in organ culture.

Foetal rat pancreatic rudiments explanted on day 14 of gestation were grown for 6 days in organ culture in medium containing glucose (5.5(1G) or 16.5(3G)mmol/l) and amino acids at the 'physiological' (1AA) or seven times the 'physiological' (7AA) concentration. Cultures were also performed in medium to which zinc sulphate had been added at 10(-7) to 10(-5) mol/l concentration. At the end of the period of culture the diameters of insulin, glucagon and zymogen granule profiles in the rudiments were compared with those in normal 20-day foetal pancreas by quantitative morphology. The beta cell volume, the number of granules per beta cell, the insulin granular volume fraction and the area of insulin granule core and halo were also measured under selected experimental conditions. Zymogen granule profiles were largest in vivo, intermediate in diameter when grown in 1G x 7AA medium and smallest in 1G x 1AA medium. The mean diameter of glucagon granule profiles remained constant for growth in vivo, in 1G x 7AA medium. Insulin granule profiles were largest in 1G x 1AA medium or in 1G x 7AA medium, smallest in 3G x 1AA mdeium and of intermediate diameter in vivo. Amino-acid enrichment increased the diameter of insulin granules and glucose enrichment decreased it. The addition of zinc to the culture medium had no effect on insulin granule diameter. In 1G x 7AA cultures the beta cells were of similar size to those in vivo, but there were 29% fewer insulin granules per cell. The increased size of the insulin granules in 1G x 7AA cultures resulted in the insulin granule volume fraction in 1G x 7AA being 17.6 compared with 10.8% in vivo. Insulin granule cores were made larger by amino-acid enrichment of the culture medium but they were unaffected by glucose. The haloes were larger in 7AA medium and smaller in 3G medium. Glucose and amino-acid enrichment had a significant interaction on halo area, the mean area in 3G x 7AA medium being less than would have been expected from the summation of the effects of the two conditions.


Possible priming effect of luteinizing hormone releasing hormone on the anterior pituitary gland in the Japanese quail and the stimulation of secretion of follicle-stimulating hormone.

After the i.m. injection of 10 micrograms synthetic LH releasing hormone (LH-RH) into Japanese quail the levels of LH and FSH in plasma rose significantly within 2 min. The increased level of LH declined rapidly but that of FSH was maintained for the duration of the experiment. To determine whether the anterior pituitary gland is primed by LH-RH a double injection schedule was adopted. It would appear that, while endogenous LH-RH may prime the avian pituitary gland slightly, synthetic LH-RH is ineffective.


Concanavalin A binding to amphibian embryo and effect on morphogenesis.

The effect of Concanavalin A (Con A) on morphogenesis in Pleurodeles waltlii has been studied. Embryos were incubated with various concentrations of the lectin for a period of 6 days. Three stages of development were examined, late blastula, young gastrula and late gastrula. In the presence of the lectin at a concentration of 200, 150 or 100 micrograms/ml morphogenic movements were delayed, altered and finally blocked. At lower concentrations, 50 or 25 microgram/ml, there was a slight delay in gastrulation, but in some cases development was normal. These findings indicate that Con A exerted an inhibitory effect on amphibian morphogenesis and there is evidence that the lectin effect was concentration dependent. The effects of Con A were specific since they were totally inhibited by alpha-methyl-D-mannopyranoside (0.05 M). The viability of the 24 h lectin-treated embryos was demonstrated by washing experiments. Labelled Con A binding to the embryos was investigated before and after discarding the vitelline membrane. The results suggest a direct interaction between Con A and the cell surface and this was confirmed by using fluorescein isothiocyanate Con A.


Failure of long surviving, passively enhanced kidney allografts to provoke T-dependent alloimmunity. I. Retransplantation of (AS X AUG)F1 kidneys into secondary AS recipients.

Long survival of (AS X AUG)F1 rat kidney allografts in AS recipients was induced by passive enhancement with AS anti-AUG antiserum at the time of grafting. After 1-3 mo, the kidney allografts were transferred to second AS recipients, either naive or sensitized against AUG tissue. Naive second recipients did not reject the grafts acutely and failed to mount T-dependent immunity against AUG targets. When later challenged with spleen cells carrying the AUG haplotype, the naive second AS recipients showed strong IgM, IgG, and cytotoxic T-cell responses after grafting, and the kidneys were rapidly destroyed by immune rejection in all but one rat. It is concluded that long-surviving kidney allografts fail to activate helper T cells and induce in naive second recipients the same state of unresponsiveness observed in the first recipient.


Failure of long surviving, passively enhanced kidney allografts to provoke T-dependent alloimmunity. II. Retransplantation of (AS X AUG)F1 kidneys from AS primary recipients into (AS X WF)F1 secondary hosts.

Long surviving, passively enhanced (AS X AUG)F1 kidneys carried by AS recipients were retransplanted into (AS X WF)F1 second hosts. Acute graft rejection did not occur. Only one of six secondary recipients mounted a significant T-dependent IgG lymphocytotoxic antibody response. In all six, generation of cytotoxic T cells was markedly slower and depressed. These results are compatible with the hypothesis that kidney parenchyma, although carrying major histocompatibility complex specificity is able to induce T-independent but not T-dependent alloimmunity. A corollary is that passenger cells are responsible for exciting the T-dependent allimmune response normally observed after grafing. The practical difficulty of eliminating all T-dependent immunogenicity from (AS X AUG)F1 kidneys was emphasized by the observation that a 3-d residence in an intermediate AS recipient was insufficient time to prevent acute graft rejection after retransplantation.


Distribution of mast-cell precursors in hematopoeitic and lymphopoietic tissues of mice.

Two experimental systems were used to investigate the origin of precursor cells which differentiate into tissue mast cells in vivo. (a) Increase of mast cell number was examined in the skin, stomach, cecum, and mesentery of genetically mast cell-depleted WBB6F1 (WB X C57BL/6)-W/WV mice after the injection of various hematolymphoid cells of congenic +/+ mice. (b) Appearance of mast cells with giant granules was studied in irradiated C57BL/6-+/+ mice after the injection of lymphoid cells of C57BL/6-bgJ/bgJ (beige, Chediak-Higashi syndrome) mice. Concentrations of mast cell precursors in the thymus, lymph node and Peyer's patch were less than 0.1% of the concentration in the bone marrow. Neither treatment of donor bone marrow cells with anti-Thy-1.2 serum and complement nor thymectomy of the recipient mice affects the development of mast cells in the skin, stomach, cecum, and mesentery. Moreover, the number of mast cells increased to normal level when the skin of WBB6F1-W/WV mice was grafted on the back of nude athymic (BALB/c-nu/nu) mice. These results indicate that mast cell precursors are derived from hematopoietic tissues rather than lymphopoetic ones and that the differentiation of the precursor cells does not depend on T lymphocytes or the thymus.


Hybrid resistance to EL-4 lymphoma cells. I. Characterization of natural killer cells that lyse EL-4 cells and their distinction from marrow-dependent natural killer cells.

Natural killer (NK) cells from nonimmunized mice capable of lysing EL-4 (C57BL/6 strain H-2b) tissue culture-adapted lymphoma cells have been analyzed and compared with NK cells which lyse YAC-1 (A-strain, H-2a) lymphoma cells. A correlation was seen in the ability of inbred and B6D2F1 mice to reject C57BL/6 (B6) bone-marrow grafts and the ability of their spleen cells to lyse EL-4 cells in vitro. This suggests that hybrid or hemopoietic histocompatibility antigens, (Hh-1b), relevant in the rejection of B6 stem cells may also be the relevant target structures for the anti-EL-4 NK cells. Certain features of these NK cells are similar to the NK cells reactive against YAC-1 cells. Both types of NK cells are present in athymic nude mice, are not affected by treatment with anti-immunoglobulin plus complement, and are not depleted by techniques that remove macrophages. NK activity against both targets is stimulated 3 d after injection of Corynebacterium parvum, and 24 h after challenge with polyinosinic:polycytidylic acid. Hydrocortisone acetate and cyclophosphamide lead to reduction of NK activity within 2-3 d after administration. However, the anti-YAC and anti-EL-4 NK reactivities differed in several important respects. Treatment of mice with 89Sr, the bone-seeking isotope, to deplete marrow-dependent cells, depleted the anti-YAC-1 but not anti-EL-4 cell functions. Anti-EL-4 NK cells were unaffected by silica particles in vivo or in vitro; the NK cells reactive to EL-4 cells matured functionally much earlier in life (5 d of age) and the function did not decline with age. Irradiated mice reconstituted with syngeneic marrow or spleen cells developed functional NK cells against EL-4 targets before they developed anti-YAC-1 NK cells in their spleen. Thus anti-EL-4 NK cells that express hybrid resistance in vitro appear to differ from anti-YAC-1 NK cells and do not require an intact marrow microenvironment for functional differentiation. Despite differences in the NK-cell types involved in the lysis of YAC-1 and EL-4 cells, these two tumor cells share certain common determinants. This was ascertained both by cold competition and by utilization of YAC-1 and EL-4 cell monolayers as immunoadsorbents. We conclude that Hh-1b is the common antigen present in EL-4 and YAC-1 cells, because B6D2F1 anti-B6 (anti-Hh-1b) cytotoxic T lymphocytes lysed both the tumor cells. Our data suggest that Hh-1b antigen is recognized by both types of NK cells, but that additional determinants must be present on YAC-1 cells. Two models of NK cell lysis compatible with the data are presented.


Effects of immobilized immune complexes on Fc- and complement-receptor function in resident and thioglycollate-elicited mouse peritoneal macrophages.

We have examined the Fc- and complement-receptor function of resident and thioglycollate-elicited mouse peritoneal macrophages plated on surfaces coated with rabbit antibody-antigen complexes and with complement. We derive four major conclusions from these studies. (a) The trypsin-resistant Fc receptors of resident and thioglycollate-elicited macrophages are completely modulated when these cells are plated on rabbit antibody-antigen complexes. Residual Fc receptor activity is a result of the incomplete modulation of trypsin-sensitive IgG2a receptors. (b) The complement receptors of thioglycollate-elicited macrophages, but not of resident macrophages, are modulated when these cells are plated on complement-coated surfaces. The capacity of the two cell types to modulate their complement receptors is correlated with their ability to ingest complement-coated erythrocytes. (c) The complement and Fc receptors of both types of macrophages move independently of one another. (d) Complement masks the Fc segments of IgG in immune complexes thereby rendering them ineffective as ligands for macrophage Fc receptors.


[Artificial endocrine pancreas (author's transl)].

16 years ago Kadish (1963) Trans. Amer. Soc. Artif. Org. 9, 363--367) published his first pioneering experiments with an extracorporal blood glucose regulating machine. These experiments were fundamental to the development of an artificial endocrine pancreas that replaces the natural regulator of the blood glucose. Enormous improvements have been done as far as analytical and computer technology and algorithms are concerned. Satisfactory but time-limited insulin therapy of problematic diabetics is feasable and benefical. However, in spite of a very great miniaturization of the analytical device, of the computer system, or of the insulin delivery pump, we are still far away from a durable, or at least long-term implantation of an artificial endocrine pancreas.


Augmentation of macrophage complement receptor function in vitro. I. Characterization of the cellular interactions required for the generation of a T-lymphocyte product that enhances macrophage complement receptor function.

The function of complement receptors of mouse peritoneal macrophages was converted in vitro from mediating only attachment of macrophage complement receptor function was achieved by treating freshly explanted macrophages with supernates from cultures containing T lymphocytes and appropriately triggered macrophages. Fc receptor-mediated phagocyctosis by macrophages was required for the production of active supernates, for neither ingestion via the cells' complement receptors nor ingestion via nonimmunologic means was a sufficient stimulus for the macrophages' participation in the generation of supernatant activity. Fc receptor-triggered macrophages interacted by a contact dependent, but histocompatibility independent, mechanism with T lymphocytes, thereby signalling the lymphocytes to elaborate the active product. The possible significance of enhanced macrophage complement receptor function in inflammation, host defense against microbial pathogens, immune complex disease, and neoplasia is discussed.


[Algorithm for extracorporal blood glucose regulation (author's transl)].

A control mechanism is described, based on a simple proportional/differential regulation. The calculation takes one minute and it takes into account glucose degradation, insulin half life in vivo, and the delay between blood sampling and insulin action on the blood glucose value. This is repeated continuously every minute (short time mode) or every 5 minutes or more (long time mode), depending on the rate of change of the blood glucose. Operator decision is based on digitally converted tables, which are analogous to the graph of proportional control, and on glucose equivalent tables, which give the insulin effect on glucose as a function of time.


[Determination of thyroxine in serum by a heterogeneous enzyme immunoassay: results of a joint trial].

This paper describes the evaluation of a heterologous enzyme immunoassay for the determination of total thyroxine in serum by a group of seven clinical chemical laboratories. The test follows the principles of the enzyme linked immunosorbent assay (ELISA) and uses peroxidase as a marker. The evaluation of analytical reliability yielded the following results within the analytical range from 39 unto 322 nmol/l: 1. Within-batch precision ranged from 3.1 unto 10.4% (coefficient of variation) with single analyses. 2. Between-batch precision ranged from 3.7 unto 20.4% with single analyses. 3. Between-laboratories precision ranged from 5.4 unto 6.8%. 4. Pure thyroxine, added to serum or thyroxine-free serum, gave recoveries between 93 and 120%. 5. Analysis of control sera gave results essentially comparable to the assigned values based upon radioimmunoassays. 6. Analysis of 288 clinical sera gave slightly higher results by the enzyme immunoassay than by the analogous radioimmunoassay from the same manufacturer. 7. Comparison with other methods of analysis (radioimmunoassays, competitive protein ligand assays, hormonal iodine assay) yielded partly comparable, partly higher results. 8. Comparison with the homogenous enzyme immunoassay (EMIT) led to comparable results. 9. Interference due to hyperlipemia or hemolysis was not observed. 10. There might be an interference in hyperbilirubinaemic sera, due to an as yet unknown factor. With respect to practicability the ELISA-test compares favourably with the analogous solid phase radioimmunoassay. The main differences are the absence of radioactive material and a longer shelf-live of reagents. Following the manual procedure the time taken to perform the enzyme immunoassay is slightly longer than for the analogous radioimmunoassay.


Evaluation of enzyme immunoassays for determination of thyroxine (EMIT, ENZYMUN) and of thyroxine binding index.

An evaluation of enzyme immunoassays for determination of thyroxine in serum (EMIT ABA thyroxine assay, Syva Corp., ENZYMUN assay thyroxine, Boehringer Mannheim) and of thyroxine binding index (ENZYMUN assay TBI1), Boehringer Mannheim) is presented. The precision of the enzyme immunoassays was adequate (coefficients of variation ranged from day to day with EMIT from 3--11% and with ENZYMUN from 4--11%). Both assays are specific and easy to perform. About 20 unknown samples can be analyzed in duplicate by EMIT within 60 minutes and by ENZYMUN within 250 minutes. A comparison of the results obtained by enzyme immunoassays and radioimmunoassay in a series of about 100 patients showed a good correlation between both methods. The precision of the ENZYMUN TBI assay was adequate (coefficient of variation from day to day 4.9%) and the thyroxine/TBI-ratio correlated well with the thyroxine/TBG-ratio.


Strategies for diagnosing vaginitis.

Detailed history, physical examination, laboratory, and follow-up data were obtained from 821 patients presenting to a primary care clinic over an 18-month period with the symptoms of vaginal infection or urinary tract infection (UTI). Information useful in deciding when to perform a vaginal examination, when to obtain various types of cultures, and when to perform microscopic examination of a saline suspension or Gram stain is presented. Of particular interest were the findings that patients with dysuria more commonly have vaginitis than UTI, the superiority of a saline examination to other means of diagnosing yeast vaginitis, and the rarity of a positive trichomonas preparation when the vaginal discharge had a curd-like appearance.


Hyperactivity: a current assessment.

Hyperactivity in children is frequently overdiagnosed and inappropriately managed. When a syndrome of hyperactive behavior associated with learning difficulties is established, aggressive multifaceted management is indicated. Many possible etiologies have been suggested, but none of these has yet been proven. It may well be that more than one etiology exists and that many children have multiple factors contributing to their illness. None of the nontraditional therapies recently receiving attention, such as the Feingold diet, have had any proven benefit, although scattered anecdotal reports and some recent controlled trials suggest that some nontraditional therapies may be of limited value in some children. The most important consideration in therapy is that of defining specific problem areas for each individual child and assuring that each is dealt with appropriately. Caution must be exercised to avoid the pitfall of using drugs as the sole modality of treatment. Finally, parental education must never be overlooked.


Patterns of mobilization of the Proteus mirabilis chromosome by R plasmids.

R plasmids R40a, Rip69, R447b, R769 belonging to incompatibility groups A-C, M, N, V, respectively, were investigated for chromosomal mobilizing ability in Proteus mirabilis. Plasmids R40a, Rip69 and R447b mediated polarized transfer of markers in a clockwise direction from origins near tyr-1, metF and ser-2, respectively, on the linkage map. The recovery frequency per donor cell of proximal markers approached 1 x 10(-4) for these three plasmids and the efficiency of chromosomal transfer was higher than that of the previously studied plasmid D. The plasmid-guided chromosomal trajectories overlap and it was possible to complement results obtained with plasmid D to assemble a time-of-entry chromosomal map and directly establish the circularity of the linkage group. The map comprises a length of 93 min in terms of transfer time. Plasmid R769 had a different pattern of chromosome transfer. This plasmid produced recombinants for all markers at frequencies of about 4 x 10(-6) per donor. It effected multiple and more or less simultaneous entry of markers and produced recombination over lengths of chromosome rarely corresponding to more than 10 min on the linkage map.


Pleiotropic aspartate taxis and serine taxis mutants of Escherichia coli.

Mutants that at one time were thought to be specifically defective in taxis toward aspartate and related amino acids (tar mutants) or specifically defective in taxis toward serine and related amino acids (tar mutants) are now shown to be pleiotropic in their defects. The tar mutants also lack taxis toward maltose and away from Co2+ and Ni2+. The tsr mutants are altered in their response to a variety of repellents. Double mutants (tar tsr) fail in nearly all chemotactic responses. The tar and tsr mutants provide evidence for two complementary, converging pathways of information flow: certain chemoreceptors feed information into the tar pathway and others into the tsr pathway. The tar and tsr products have been shown to be two different sets of methylated proteins.


Isolation by differential and zonal centrifugation of minicells segregated by Escherichia coli.

Minicells segregated from Escherichia coli chi925 carrying a drug-resistance plasmid were separated from nucleated cells by differential centrifugation and purified by rate-zonal centrifugation in sucrose gradients. Minicells purified in this way were capable of donating the plasmid to nucleated cells. They also incorporated thymidine, uridine and methionine into macromolecules. Methods are described for purification of plasmid-containing minicells on a scale large enough to allow isolation of DNA, DNA polymerase and RNA polymerase in sufficient quantities for studies of enzymes involved in replication and transcription of plasmid DNA.


The pools of ribosomal proteins and ribosomal ribonucleic acids during relaxed control of Escherichia coli A19 (Hfr, rel met rns).

The soluble fraction extracted from Escherichia coli A19 (Hfr, rel met rns) during early and late times of phenotypic and genotypic induced relaxed control have been examined for the possible accumulation of ribosomal proteins (r-proteins) and rRNA species during this time of unbalanced macromolecular synthesis. Ribosomal proteins and rRNA species were not found to accumulate within the soluble fraction at any time during this period of relaxed control; even after the typical rRNA accumulation had ceased, r-proteins did not accumulate. It is concluded, from these and related observations, that the r-proteins and rRNA species known to be produced during relaxation must immediately associate to form the unusual ribonucleoprotein particles (e.g. 'relaxed particles' and 'chloramphenicol particles') characteristic of periods of relaxed control. Since r-proteins do not accumulate even when net RNA accumulation halts, it appears that some elements of the normal, basic co-ordination between rRNA and r-protein synthesis/stability persist even during relaxed control.


Differences between the anthranilate-5-phosphoribosylpyrophosphate phosphoribosyltransferases of Salmonella typhimurium strains LT2 and LT7.

The anthranilate-5-phosphoribosylpyrophosphate phosphoribosyltransferases (PRT), coded by the second structural gene (trpB) of the tryptophan (trp) operon in strains LT2 and LT7 of Salmonella typhimurium, differ from each other in a number of parameters. These include the apparent Km values for their substrates anthranilic acid and 5-phosphoribosylpyrophosphate, thermostability, sensitivity to substrate inhibition by anthranilic acid, as well as end-product inhibition by tryptophan and specific activity. The PRT of strain LT7 further differs from that of strain LT2 in that its apparent Km for 5-phosphoribosylpyrophosphate is three to seven times higher when associated with anthranilate synthase in the enzyme complex which catalyses the first two steps of tryptophan biosynthesis than in its free uncomplexed form, which the PRT of strain LT2 shows the same apparent Km for this substrate in both its free and complexed forms. These results confirm and extend the finding of Stuttard (1975) that strains LT2 and LT7 differ genetically form each other at a single site within region II of the trpB gene.


Studies on the interaction of Mycobacterium microti and Mycobacterium lepraemurium with mouse polymorphonuclear leucocytes.

When polymorphonuclear leucocytes (PMN) elicited in mice were infected with Mycobacterium microti or Mycobacterium lepraemurium, phagosome-lysosome fusion occurred with both species. This contrasts with the situation in macrophages where phagosome-lysosome fusion is inhibited by M. microti but not M. lepraemurium. No evidence was found for killing of M. microti or M. lepraemurium when the bacteria were isolated from PMN and their viability tested in cell-free medium or macrophages.


High and low toxin production by a non-toxigenic strain of Clostridium botulinum type C following infection with type C phages of different passage history.

Toxin production in Clostridium botulinum types C and D is governed by specific bacteriophages. Prior passages of a phage controlling type C toxin production caused subsequently lysogenized bacteria to become variably toxigenic. This appears to be one of the causes of the decrease in toxigenicity which is common in some type C and D strains. The morphology of bacteria was also changed from rod-shaped to filamentous by infection with a successively propagated phage.


Host modification of chlamydiae: differential infectivity for cell monolayers of chlamydiae grown in eggs and monolayers.

Cell monolayer-grown chlamydiae (CGO) differed from egg-grown organisms (EGO) in their increased spontaneous infectivity relative to centrifuge-assisted infectivity for monolayers. For each population spontaneous: centrifuge-assisted infectivity ratios were constant over a wide dose range. Spontaneous infection increased linearly with time and could not be exhausted from either population by prolonged adsorption; there was no change in infectivity ratios in residual supernatants. Further, one passage of EGO through monolayers gave CGO with stable infectivity properties not increased by further cell passage yet reverting on a single passage in eggs. Spontaneous infection of monolayers with EGO gave progeny with the same infectivity ratios as monolayers infected with EGO by centrifugation. The change in properties following EGO infection of monolayers occurred prior to natural release from cells. We conclude that EGO and CGO are two phenotypically distinct, homogeneous populations. The two infection modes are not properties of subpopulations within EGO and CGO. The relationship of these observations on chlamydiae to other possible host-imposed phenomena is considered.


Host modification of chlamydiae: presence of an egg antigen on the surface of chlamydiae grown in the chick embryo.

Egg-grown chlamydiae (EGO) have a yolk sac antigen assoicated with their surface which is absent from cell monolayer-grown organisms (CGO). EGO infectivity was specifically neutralized by rabbit antiserum to normal yolk sac; CGO infectivity, before or after incubation with normal yolk sac material, was not neutralized. Treatment of EGO with Clostridium welchii culture filtrate, containing phospholipase C, abolished spontaneous infectivity for monolayers and neutralization by anti-yolk sac antiserum but did not affect centrifuge-assisted infectivity. The possible significance of host antigen on the chlamydial surface is considered.


Transduction of fimbriation demonstrating common ancestry in FIRN strains of Salmonella typhimurium.

The production of fimbriate (Fim+) recombinants was observed in transductional crosses between different pairs of wild-type strains of different biotypes of Salmonella typhimurium. Fim+ recombinants were readily produced in transductions from Fim+ donor strains to Fim- recipient strains and, less frequently, between some pairs of Fim- strains, for example, between almost any strain of the firn biogroup (Fim- Inl- Rha- Bxyl-) and many strains of the non-FIRN Fim- biogroup. None of numerous crosses between different pairs of FIRN strains gave Fim+ recombinants, suggesting that the fim mutation was present at the same intragenic site in all FIRN strains. FIRN strains are thought to have descended from a single ancestral FIRN bacterium which originated by a series of mutations from a strain of the common biotype 1a (Fim+ Inl+ Rha+ Bxyl+). Two FIRN-like (Fim- Inl+ Rha- Bxyl-) strains that did not yield Fim+ recombinants in crosses with FIRN strains were probably wild-type Inl+ mutants from FIRN strains.


Location of binding sites on common type 1 fimbriae from Escherichia coli.

Common type 1 fimbriae were isolated from Escherichia coli and their length distribution profile was determined before and after treatment with ultrasound. As fimbriae were shortened, so their haemagglutinating capacity decreased, but their ability to bind to erythrocytes did not decrease to the same extent. Isolated fimbriae did not agglutinate inside-out vesicles prepared from horse erythrocytes or liposomes, suggesting that the binding mechanism was not based on non-specific hydrophobic interactions. The results support a lateral rather than a terminal location for the fimbrial binding site responsible for haemagglutination.


Salmonella phage glycanases: substrate specificity of the phage P22 endo-rhamnosidase.

Interaction between phage P22 and phenol-water extracted lipopolysaccharides from sensitive Salmonella bacteria belonging to serogroups A, B and Di results in hydrolysis of the alpha-L-rhamnosyl linkages within the tetrasaccharide repeating unit of the O-antigenic polysaccharide chain. These O-antigens have identical structures except for the nature of the 3,6-dideoxy-hexosyl group linked to O-3 of the D-mannosyl residue. Removal of the dideoxysugar, or periodate oxidation followed by borohydride reduction of the L-rhamnosyl residue made the O chain resistant to the endo-rhamnosidase. Substitution of the D-galactosyl residue at O-4, but not at O-6, with an alpha-D-glucosyl group was compatible with hydrolysis. A number of Klebsiella pneumoniae and Shigella flexneri lipo- or capsular polysaccharides containing chain L-rhamnosyl residues were tested but none was sensitive to the P22 endo-rhamnosidase. The substrate specificity of the endo-rhamnosidase parallels the lytic specificity of the phage which suggests that the initial step in phage P22 infection is a P22 tail enzyme O-antigen substrate interaction. The main product of the hydrolysate was octa-, dodeca- and hexadecasaccharides. Treatment of phage FO resistant smooth strains of S. typhimurium with P22 tails removed O polysaccharide chains and made previously 'hidden' FO receptors accessible to the phage.


Hemolysis-in-gel test in immunity surveys and diagnosis of rubella.

The hemolysis-in-gel (HIG) technique was adapted for rubella antibody determinations. Use of sucrose gradient purified virus and its coupling with CrCl3 to chicken erythrocytes resulted in gel plates that could be stored for several weeks and were suitable for reproducible antibody determinations. In a serological survey of young healthy adults the HIG values (range less than 2--13 mm) were in close correlation to those obtained by the HI test (less than 10 5o 320). The Hig test seems well suited for screening the need of vaccination. Seronegative sera (HIG less than 2,HI less than 10) gave without heat inactivation hemolysis zones ranging from 4 to 6.5 mm. Although the present rubella HIG test did not measure IgM antibodies, the test, by virtue of its accuracy and sensitivity--extending to antibody levels corresponding to HI titers 2--10--provides a simpler and more rapid means for diagnosis of rubella infections than the conventional HI and CF tests.


Hepatitis B core antibody in volunteer blood donors: comparison of radioimmunoassay and indirect immunofluorescence.

The results of a pilot study on the prevalence of anti-HBc in HBsAg negative volunteer blood donors are presented. Two techniques for anti-HBc determination were compared--radioimmunoassay (RIA) and indirect immunofluorescence (IF). In a panel of 56 sera with known HBV markers, RIA was found to be significantly more sensitive than IF, and both techniques were specific. Out of 2,000 HBsAg negative blood donor sera tested by RIA, 46 (2.3%) were found positive for anti-HBc. In 24/24 sera, the specificity of the anti-HBc was confirmed. Also 37/46 (80.4%) anti-HBc positives were found positive for anti-HBs, leaving 9/2,000 (0.4%) blood donors positive only for anti-HBc. It is concluded that it would be premature to advocate the introduction of anti-HBc as a routine screening test of blood donors.


Effect of acute stress on the absorption and distribution of zinc and on Zn-metallothionein production in the liver of the chick.

A study has been made of the effects of chloroform inhalation, Escherichia coli endotoxin injection and hydrocortisone injection on the absorption of a single intragastric dose of 65Zn by the chick. Injection of hydrocortisone increased the absorption of the 65Zn by 30-55% in both Zn-deficient and Zn-supplemented chicks. The influence of chloroform and endotoxin was less consistent; the former treatment only increased 65Zn absorption and endotoxin was less consistent; the former treatment only increased 65Zn absorption in Zn-supplemented chicks fed ad libitum whereas endotoxin only increased that in Zn-supplemented chicks on a restricted food intake. Injection of endotoxin increased the hepatic uptake of the absorbed 65Zn in both Zn-deficient and Zn-supplemented chicks, whereas hydrocortisone had a similar effect in the Zn-supplemented birds only. Chloroform inhalation increased hepatic 65Zn uptake in Zn-deficient chicks only. The increase in hepatic Zn concentrations in the stressed chicks was mainly associated with a protein in the cytosol identified as metallothionein. Both endotoxin and hydrocortisone decreased total plasma Zn concentrations in Zn-supplemented and Zn-deficient chicks; chloroform decreased plasma 65Zn content only.


Neurosurgery at the crossroads: leadership role of the American Association of Neurological Surgeons. The 1979 AANS presidential address.

The President of the American Association of Neurological Surgeons (AANS) reviews the formative history of the major neurosurgical societies, together with their agreement to consolidate their efforts in the joint AANS. As a united group, the Association has been effective in carrying out relations with other professional organizations and with government. Long-range planning is being pursued steadily to increase the role of organized neurosurgery in maintenance of, and improvement in, patient care, education, and research.


Anterior cervical discectomy and interbody fusion. An experimental study using a synthetic tricalcium phosphate.

This study evaluates the histological and histochemical changes and osteogenicity of Synthos (tricalcium phosphate ceramic) implanted in the cervical intervertebral space. The cervical vertebrae from C-3 to C-6 were exposed in 20 dogs, and discectomy was performed at the third and fifth spaces. A dowel of Synthos was inserted into the third space, and a piece of fresh autologous graft from the humerus was inserted into the fifth space. The animals were divided into five groups with four animals in each. Four animals were sacrificed at each of 3, 6, 12, 18, and 22 weeks after the procedure. The C-3 to C-6 vertebrae were removed en bloc. One-half of each specimen was processed for histological examination of bone development, while the other half was processed for the two-color fluorescent labeling technique of Suzuki and Matthews for determination of osteogenesis at the time of operation and sacrifice. Various degrees of compression of the Synthos dowel were noted, with anterior and/or posterior displacement of the implant in 70% of the cases. Results indicate that the Synthos implant was biochemically and biomechanically unacceptable for the purposes of this investigation.


Iliac crest fracture after removal of two bone plugs for anterior cervical fusion. Case report.

A case is reported in which the iliac crest fractured following removal of two bone plugs. The plugs had been removed for use in a double cervical vertebral body fusion operation by the method of Cloward.


Comparative susceptibility of starch granules of double- and triple-mutants containing amylose-extender, waxy, sugary-1, sugary-2 and dull genes of maize inbred OH43 (Zea mays L.) to amylase.

Starch granules were prepared from 14 double- and 26 triple-mutants containing amylose-extender (ae), 14 double- and 18 triple-mutants containing waxy (wx), 15 double- and 20 triple-mutants containing sugary-1 (su1), 13 double- and 23 triple-mutants containing sugary-2 (su2), and 14 double- and 19 triple-mutants containing dull (du) of maize inbred Oh43 (Zea mays L.). The relative susceptibilities of these starch granules to fungal glucoamylase were determined and the starch granules were examined by scanning electron microscopy. A commercial normal maize starch was used as a control. Starch granules of the double- and triple-mutants containing su1 and su2 were digested two to eight times faster than normal. The ae gene reduced susceptibility and seems to be epistatic to su1 and su2. Starch granules of the double- and triple-mutants containing wx were digested about two times faster than normal and those containing shrunken-2 (sh2) were digested 1.2 to eight times faster than normal. Starch granules of triple-mutant combinations with opaque-2 (o2) showed digestion properties which were comparable to those of their respective monopaque double-mutant counterpart.


Cellular survival of human marrow during placement of marrow-cancellous bone grafts.

The survival of human marrow cells during the placement of marrow-cancellous bone grafts was studied by three independent viability assays. Marrow cells are resistant cells able to survive the surgical harvest from the ilium. Salt solutions such as normal saline solution and 5% dextrose in water (D5W) were superior to tissue culture medium, the serum of the patients, and several other solutions in supporting the survival of the graft cells. High survival rates of marrow cells stored in normal saline solution and D5W for four hours or less established that 95% to 100% live cells can be transplanted even with long delays between harvest and placement of the graft.


Timing, results, and complications of mandibular reconstructive surgery: report of 32 cases.

Sufficient information concerning the difficulties encountered in reconstructive surgery is rarely provided in the literature. This study, which was performed on 32 patients, points out a high rate of complication; major and minor complications were encountered in 68.8% of the patients. Benign and traumatic lesions caused the fewest problems. Malignant lesions, particularly those receiving radiotherapy, had the greatest incidence of complications. Successful reconstruction was accomplished in 75% of the cases. The use of a corticocancellous autogenous graft is suggested in selected cases of malignant disease.


Suppressed responsiveness to gonadotropin-releasing hormone in girls with unsustained isosexual precocity.

Eleven girls, ages 10/12 to 76/12 years, were evaluated because of early and rapid breast development. Initial clinical presentations and serum gonadotropin or estradiol determinations did not differentiate patient types. However, patients could be divided into two groups based on their responses to synthetic gonadotropin-releasing hormone: Group A consisted of seven girls with suppressed or prepubertail-type responses, and Group B consisted of four girls with pubertal or adult-type responses. Subsequent evaluation revealed that Group A patients had intermittent or unsustained isosexual precocity, whereas Group B patients had isiopathic prococious puberty. During initial evaluation, increased serum or urinary estrogen values were noted in ten of ten patients who were studied. The greatest serum E2 values (162 and 117 pg/ml) were noted in two Group A patients; three months and two years later, those patients had normal prepubertal responses to GnRH and serum E2 values of less than 4 and 14 pg/ml, respectively. Unsustained sexual precocoity in girls may be secondary to autonomous ovarian production of estrogens, and the GnRH test may be useful in evaluation of girls with isosexual precocity.


Familial nesidioblastosis: severe neonatal hypoglycemia in two families.

Severe neonatal hypoglycemia with pathologic findings of diffuse nesidoblastosis of the pancreas is described in five children of both sexes from two families with unaffected parents. This appears to represent an autosomal recessive disorder of pancreatic development. Despite extensive testing, the diagnosis of hyperinsulinism was difficult in the index case of each family and delayed definitive treatment. Medical therapy with steroids and diazoxide was unsuccessful; pancreatectomy was required to treat persistent hypoglycemia. An abnormality of circulating glucagon found in one child with this disorder suggested that hyperinsulinism may not be the sole hormonal imbalance present, but rather that this disease is one of generalized disturbance of islet cell function. The history of severe, persistent neonatal hypoglycemia in an older sibling should lead the physician to investigate subsequent children for the presence of asymptomatic hypoglycemia.


Synchronization of Plasmodium falciparum erythrocytic stages in culture.

Synchronous development of the erythrocytic stages of a human malaria parasite, Plasmodium falciparum, in culture was accomplished by suspending cultured parasites in 5% D-sorbitol and subsequent reintroduction into culture. Immediately after sorbitol treatment, cultures consisted mainly of single and multiple ring-form infections. At the same time, varying degrees of lysis of erythrocytes infected with the more mature stages of the parasite was evident. Approximately 95% of the parasites were in the ring stage of development at 48 and 96 hr after sorbitol treatment-likewise, a high percentage of trophozoite and schizont stages was observed at 24, 72, and 120 hr. D-Mannitol produced similar, selective, lytic effects.


Steroids and bag and mask ventilation in the treatment of acute epiglottitis.

A non-instrumentation treatment protocol for acute epiglottitis that features the use of dexamethasone to reduce edema and positive pressure ventilation by bag and mark to support ventilation, if needed, has been used in 40 cases, 1974--1977, with no mortality. The presence of the airway specialist (pediatric surgeon) in the Intensive Care Unit with the patient further assured the airway. The importance of having a protocol in place that is workable for the specific local circumstances of each institution is emphasized.


The government and the inguinal hernia.

Our review of the incidence of inguinal hernias in children based on socioeconomic differences and their risk of incarceration with its subsequent complications, was prompted by a governmental decision to disallow elective herniorrhaphy in children over 1 yr of age. The review showed the following: The risk of incarceration, the failure of preoperative reduction and the potential gonadal injury is more than three times as high in the poor child, usually covered by Medicaid. Since operative and postoperative complications increase proportional to the incidence of incarcertain, the denial of an elective herniorrhaphy endangers the life of a child. Since the increased hospitalization after incarceration also increases the financial expenditure, this rule is not only medically but also economically unsound. This review suggests that unilateral governmental health care decisions, especially those aimed at cost containment, should be carefully scrutinized to determine what price not only the society, but the patient has to pay for the "cost containment". We feel that the price of the denial of a herniorrhaphy is too high.


Periosteal activation and root demineralization associated with the horizontal sliding flap.

A sliding flap technique for covering denuded root associated with periosteal activation and root demineralization "in situ" was described. The possible biological mechanisms involved were discussed. Two clinical cases were presented illustrating the successful results that can be achieved.


Comparison of healing following periodontal surgery with and without dressings in humans.

Seven patients with chronic moderate to severe generalized periodontitis requiring periodontal flap surgery were selected for study. Internally beveled full thickness, apically positioned flaps with osseous recontouring were performed in 20 quadrants. Half the quadrants received a noneugenol dressing, and the other half were left undressed. Fluid Index, Gingival Index, inflammatory index, pocket depth and patient comfort were studied up to 16 weeks postoperatively. Results showed no difference in these parameters between quadrants where periodontal dressings were or were not used following surgery. The patients reported more pain and discomfort and the pain and discomfort was more severe postoperatively when the dressing was used. The results of this study suggest that a surgical dressing serves no useful purpose when periodontal flap surgery is performed.


The histopathogenesis of acute ulcerative gingivitis.

The present study was a preliminary histological and immunofluorescent investigation of the edge of the ulcer in acute ulcerative gingivitis. The results of this study show that the lesion is dominated by polymorphonuclear leukocytes, with plasma cells present in the deeper parts. The epithelium on the edge shows widening of the intercellular spaces with destruction of the epithelial cells, accompanied by a heavy infiltrate of PMNs. Both IgG and C3 could be demonstrated between these epithelial cells, although the present study could not establish whether this represented immune complex deposition. The histopathogenesis of AUG therefore seems to involve a PMN infiltration of the epithelium, with subsequent destruction of the epithelium, probably due to the release of hydrolytic enzymes. The presence of the PMNs within the epithelium may involve direct bacterial chemotaxis and/or the activation of complement via the classical or alternative pathways.


The evaluation of the periotron.

These preliminary investigations seem to indicate that the periotron may be useful in assessment of the presence of gingival inflammation in the clinical periodontal pockets. Successive recordings of the same volume varied from 5 to 11%. Data from the periotron showed a high correlation with increased known volumes of fluid and with assessment of gingival inflammation using the GI. Assessment with the periotron varied with the dissipation constant of fluids. Since the dissipation constant of gingival fluid varied among individuals, this constant must be evaluated when the instrument is used in clinical and research efforts.


MMPI results of male candidates for transsexual surgery.

The MMPI was administered to a group of 27 male transsexual candidates for sex change surgery, and their test results were compared with those of 24 male kidney transplant surgical candidates and 26 males suspected of having a psychophysiological disorder. The data revealed a notable absence of psychopathology among the transsexuals as well as the kidney patients, while the psychophysiological patients showed the expected elevations in the Hypochondriasis, Depression, and Hysteria scales. The results were in keeping with previous research of male-to-female sex change candidates that reject the notion that transsexuals invariably suffer major emotional disturbance.


Structural biochemistry XIII: Synthesis of luteinizing hormone-releasing hormone modification [Trp8]-LH-RH.

A fragment condensation method was utilized for synthesis of the Trp8-substituted luteinizing hormone-releasing hormone (LH-RH). tert-Butoxycarbonyl protection was employed for the alpha-amino positions, and benzyl protection was used for the phenol group of Tyr and the imidazole nitrogen of His. Peptide bond-forming reactions were performed using N-hydroxysuccinimide (for Trp), dicyclohexylcarbodiimide-1-hydroxybenzotriazole, 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide hydrochloride, or mixed carbonic anhydride methods. Biological evaluation of [Trp8]-LH-RH indicated no luteinizing hormone-releasing activity or inhibition of luteinizing hormone release over the dose ranges studied.


Endogenous prostaglandins and stimulated gastric secretion in the cat: the effect of various secretory inhibitors.

1. The effects of cimetidine, somatostatin and atropine upon the outputs of acid, pepsin, prostaglandins (PG) E and F in gastric juice secreted in response to i.v. infusions of pentagastrin and histamine (H) have been studied in the conscious gastric fistula cat. 2. At constant rate infusions secretion of PGE occurs and follows a similar pattern to that of gastric acid. However the ratio of H:PGE varies considerably and to an extent inexplicable in terms of assay variation. 3. Inhibition of acid output is matched by inhibition of the output of PGE, but changes in concentration of PGE suggest this is a volume related phenomenon. 4. It is concluded that gastric juice PGE is most unlikely to have a regulatory effect upon acid secretion.


Diuresis from left atrial receptors: effect of plasma on the secretion of the Malpighian tubules of Rhodnius prolixus.

1. Stimulation of left atrial receptors by distension of a balloon in the lumen of the left atrium of anaesthetized dogs was shown to result in an increase in urine flow. Plasma samples obtained from these dogs during control periods and during periods of stimulation were applied to the Malpighian tubules of Rhodnius prolixus. 2. It was found that the tubules suspended in test plasma secreted at a significantly lower rate than those suspended in control plasma. 3. These differences were also evident in extracts of plasma prepared using the solvent n-butanol. 4. Cutting or cooling the cervical vagi abolished these differences along with the increase in urine flow. It is argued that this preparation of the Malpighian tubule of Rhodnius prolixus could be used as a means of detecting the diuretic agent responsible for the increase in urine flow.


Tissue response to posterior denture base-type pontics.

Several factors have been presented that must be evaluated when selecting an appropriate posterior pontic design. Because of the controversy that exists with regard to using posterior denture base pontics, a long-span fixed partial denture was followed for 14 months. Results indicate that tissue health can be maintained, while tissue proliferation is inevitable. There is no one posterior pontic design that can be used to satisfy all requirements. Optimal pontic design can be accomplished only if each situation is evaluated on an individual basis and an appropriate design selected. Further controlled longitudinal clinical research of pontic design is mandatory for expansion of the ability to predict optimal prognosis.


Casting a gold alloy to embedded precision attachment metals.

The technique for casting a gold alloy to embedded attachment metals has been described. The joints of gold alloy cast to commercially available attachment metals were examined with a metallurgic and a scanning electron microscope. The investigation indicated that an uninterrupted gapless joint is possible, and that some diffusion occular along the interfaces with some attachment metals. In view of these findings, it is concluded that this technique can be recommended as a dental laboratory procedure.


Stress analysis of disjunct removable partial dentures.

The (1) tooth-supported, (2) ridge-supported, and (3) tooth- and ridge-supported variations of the disjunct removable partial denture were studied. When testing loads were applied to three sites, bilaterally and unilaterally, it was found that the stresses were highest when the removable partial framework was tooth-support. No significant difference was recorded between the ridge-supported partial denture and the tooth- and ridge-supported partial framework. Further refinement of the pinsleeve mechanism may be necessary to effect better control over the distributions of the stresses.


Pitting corrosion for retaining acrylic resin facings.

1. Pitting corrosion provides undercuts suitable for retaining a resin facing. 2. Using a cathode with a proper shape, pits were uniformly distributed on the surface of a metal casting. The size of pits varies, depending on the time of pitting treatment. 3. The retentive pits were excellent in both retentive strength and marginal sealing when compared with spherical powder and beads.


Effectiveness of porcelain repair systems.

The study indicates that the repair system using a bonding agent with acrylic resin is significantly stronger than the repair system using a specific composite resin. On the basis of this study, the acrylic resin repair system has the best potential for clinical success in porcelain-to-porcelain repairs.


Evaluation of resin die materials.

Some mechanical properties, physical characteristics, and manipulative features of three resin-based die materials were assessed. Advantages afforded by the strength and hardness of the test materials were overshadowed by relatively long setting times, incompatability with certain impression materials, and polymerization shrinkage. All dies aged beyond 24 hours were found to be unsuitable for use in precision fixed phosthodontic procedures.


Carbon-coated subperiosteal dental implants for fixed and movable prostheses.

Subperiosteal dental implants are not intended to replace conventional dentistry but provide an alternative method of treatment for the patient who cannot otherwise tolerate a dental prosthesis. Success can be achieved in the maxillae and in the mandible without the risk of serious complications. There are good prospects for a long-term favorable prognosis when appropriate surgical and prosthodontic criteria are observed.


Nonfunctional and functional occlusal contacts: a review of the literature.

A review of the literature on occlusal contacts emphasizes the following points. 1. Contacts in centric occlusion do not correspond to any ideal occlusal diagram. 2. Canine protection and group function appear to correspond to two successive states of the evolving dentition under the effect of abrasion. In most lateral occlusions, two maxillary teeth, of which one is the canine, are involved. 3. During mastication, tooth contacts exist. They occur most often during a sliding movement in which the direction and the origin are variable. This justifies the concept of an occlusal field of mastication. 4. During unilateral mastication, the chewing of the food is performed by working as well as nonworking contact. This imposes the distinction between the chewing and nonchewing sides (functional) and the working and nonworking sides (kinematic). 5. Centric occlusion is the occlusion most often used during mastication. It is also the occlusion for which the masticatory forces are the greatest. 6. The bibliographic data concerning occlusal contracts during swallowing are largely contradictory. It nevertheless seems that the occlusal contacts obey laws nearly the same as those governing the occlusal contact during mastication (sliding on an occlusal field of deglutition, and the importance of centric occlusion).


The cosmetic overdenture.

A technique has been described to show how a deviated midline, missing lateral incisor, and diastema were corrected with a cosmetic overdenture for a patient who is a professionl model. Irreversible procedures were unnecessary on an otherwise acceptable and functional dentition.


Border molding in mandibular denture impressions.

A modification of the border molding technique for lower dentures has been presented to increase the accuracy of this procedure.


Simplified method for removing intraradicular posts.

A technique for post removal prior to endodontic or restorative retreatment procedures has been presented. This simplified procedure is not only highly efficient, but also reduces or eliminates risks encountered in other treatment modalities.


Plasmodium falciparum in culture: improved continuous flow method.

A new design of flow vessel provides a method for continuous culture of P. falciparum in a settled layer of human erythrocytes with a slow flow of culture medium over them. The parasitemia is kept fluctuating from approximately 1%, just after addition of fresh erythrocytes, to approximately 10%, 2 or 3 days later. Each vessel provides each week 3 harvests, each containing approximately 0.6--1 X 10(9) parasites.


Observations on gametogenesis in Plasmodium falciparum from continuous culture.

Gametocytes of Plasmodium falciparum were produced in continuous cultures but eventually declined in numbers after 3--4 months in vitro. Their development progressed in a consistent pattern, from small rounded, through triangular, to ellipsoidal, and finally after 8 days to crescentic forms. Morphologic maturity occurred at 8--9 days, but the gametocytes would not exflagellate in vitro, even after 14--18 days of development. Thus, current culture methods cannot produce a continuous supply of functional gametes for further studies.


Oestrus, time of ovulation, ovulation rate and conception rate in progestagen-treated ewes given Gn-RH, Gn-TH analogues and gonadotrophins.

The influence of Gn-RH, hCG and a PMSG-hCG mixture (PG600) on the time of ovulation, ovulation rate and on the occurrence of oestrus in ewes treated with progestagen-impregnated sponges for 12 days examined. The effects of Gn-RH analogues on plasma LH, oestrus, ovulation and conception rate were also investigated. Six separate experiments were carried out. When 50 micrograms Gn-RH were given 24 h after sponge removal ovulation occurred in 44--46% of ewes within 24 h and in all ewes by 34 h. Gn-RH was a more potent ovulation synchronizer than hCG. Both hCG and PG600 reduced the incidence of overt oestrus. Gn-RH also had this effect in ewes treated during February and May but not in August and September. Gn-RH analogues given 2 days before sponge removal significantly increased ovulation rate. The display of oestrus was not affected in ewes treated 2 days before sponge removal but was suppressed in 43-69% of ewes treated with an analogue at the time of sponge removal. Ovulation occurred in 50-62% of ewes within 30-35 h of injection of Gn-RH analogues, regardless of the time of their administration. The release of LH in response to one analogue was not influenced by the presence of the progestagen-impregnated sponge in the vagina. When given a Gn-RH analogue 2 days before sponge removal or at the time of sponge removal 63 and 62% of mated ewes became pregnant compared with 70% of control ewes.


Oestrous and ovarian activity in a female jaguar (Panthera onca).

The mean +/- s.e.m. duration of oestrus was 12.0 +/- 1.0 days (n = 7) and the oestrous cycle length was 47.2 +/- 5.4 days (n = 6) for a captive jaguar. Ovulation did not occur spontaneously, but was induced by treatment with hCG or LH-RH.


Differential release of LH and FSH in cyclic mares in response to synthetic Gn-RH.

Mares at different stages of the oestrous cycle were given a single intravenous injection of 0.5 mg synthetic Gn-RH. The mean area of the induced LH peak was significantly less at mid-cycle (Day 10-11) than at any other time. The mean height of the LH peak above preinjection concentration was greater at late oestrus and early cycle (Day 5-6) than at mid-cycle and early oestrus. There were no significant different in mean FSH responses. The LH:FSH ratio for both height and area of induced peaks was significantly less at mid-cycle than at other times of injection. These results suggest that one releasing hormone could cause the release of both FSH and LH in the normal cyclic mare.


Effect of suppression of plasma prolactin on ovulation, plasma gonadotrophins and corpus luteum function in LH-RH-treated anoestrous ewes.

Nineteen Scottish Blackface ewes were given LH-RH (3 X 30 micrograms i.v., 90-min intervals) during anoestrus when prolactin levels were elevated. Plasma levels of prolactin were suppressed with CB 154 (twice daily, i.m.) on Days -5 to 0 (N = 5), 0 to +5 (N = 5) or -5 to +5 (N = 5) around the day of LH-RH treatment (Day 0). Control animals (N = 4) received saline on Days -5 to +5. Nine animals ovulated forming corpora lutea as judged by laparoscopy on Day +7. No difference in FSH or LH levels was found between treatments and ovulations occurred equally in all treatment groups. Progesterone levels were less than ng/ml in all animals up to Day 14. It is concluded that short-term suppression of prolactin does not affect the incidence of ovulation or corpus luteum progesterone production in LH-RH-treated anoestrous ewes.


Further investigation of the antiovulatory effects of the antiprogestational steroid RMI 12,936 in the rat.

Inhibition of ovulation by RMI 12,936 was associated with suppression of the pro-oestrous peak of hypothalamic dopamine. The antiovulatory effect was not reversed by administration of oestrogen, was partly reversed by progesterone and was fully reversed by oestrogen and progesterone. Hypophysial sensitivity to LH-RH, known to be reduced by RMI 12,936, remained low when ovulation was restored by steroid treatment. Administration of oestrogen did not restore the pro-oestrous peak of hypothalamic dopamine and ovulation was not induced following administration of L-DOPA in RMI 12,936-treated animals. It was concluded that RMI 12,936 is antioestrogenic as well as antiprogestational, that oestrogen is necessary for induction of full hypothalamic-hypophysial responsiveness to progesterone and that a hypothalamic dopaminergic pathway may have a non-essential role in the control of ovulation possibly associated with increasing hypophysial sensitivity to LH-RH.


Induction of follicular development and ovulation in seasonally acyclic mares using gonadotrophin-releasing hormones and progesterone.

Deeply acyclic (seasonally anovulatory) mares were treated with GnRH or a GnRH analogue to induce follicular development and ovulation. Courses of GnRH (3--4) were administered at approximately 10-day intervals to reproduce the gonadotrophin surges which precede ovulation in the normal cycle. Exogenous progesterone was administered in an attempt to reproduce the luteal phase pattern. Induced serum FSH concentrations were comparable to those causing follicular development in the normal cycle, but induced LH levels were lower and of shorter duration than those of the periovulatory surge. Three of 4 mares treated with GnRH appeared to ovulate, but did not establish CL. Nine of 10 mares given GnRH analogue also developed follicles during the final treatment course, as did mares treated with progesterone only, while only 1 of 5 untreated control mares showed any ovarian development. Failure to induce final follicular maturation and CL development by this treatment regimen may be due to an inadequate LH surge at the time of the expected ovulation associated with the low preovulatory oestradiol-17 beta surge, possibly caused by the preceding FSH stimulation being inadequate or inappropriate. Progesterone treatment increased baseline FSH concentrations in GnRH-treated mares, and also stimulated follicular development in mares not treated with GnRH, indicating a possible role for progesterone in folliculogenesis and, indirectly, ovulation.


Localization of gonadotrophin-releasing hormone (GnRH) in the hypothalamus of ovariectomized pony mares by season.

Fifteen Pony mares, ovariectomized during the previous summer, were randomly assigned to three seasonal treatment groups, winter, spring and summer (N = 5). At the designated season, the animals were killed and hypothalamic areas were collected and assayed by radioimmunoassay for gonadotrophin-releasing hormone (GnRH) activity. The hypothalamic areas were sectioned into 54 5-mm cubes to determine the sites of GnRH storage. Maximum immunoreactive GnRH activity was located in an oblique pattern extending from the arcuate nucleus-median eminence area to the anterior hypothalamic area dorsally and anteriorly. While total hypothalamic GnRH concentrations were not significantly different among seasons (P greater than 0.05), there was a trend towards increasing concentrations in the summer season. Distribution of GnRH activity was significantly different among seasons (P less than 0.05), the change in distribution occurring in the ventral to dorsal plane, as well as anteriorly to posteriorly.


Interaction of oestradiol and gonadotrophin-releasing hormone on LH release in the mare.

Acyclic mare given oestradiol for 3 days to simulate the preovulatory plasma oestradiol surge showed a non-significant 37% decrease in plasma LH during treatment. When GnRH analogue injections were given with oestradiol on Days 1--3, oestradiol had no effect on each GnRH-induced LH increase, but LH increases were more prolonged following subsequent GnRH injections on Days 4--7 when oestradiol was no longer being given. A much greater prolongation of LH release occurred when the course of GnRH injections was commenced after oestradiol treatment ceased; the LH response was almost identical to the prolonged periovulatory LH surge of the normal cycle. Therefore, it appears that the timing of the oestradiol surge, in relation to other hormonal events, is critical in inducing the uniquely prolonged periovulatory LH surge of the mare.


Effects of synchronization and frequency in insemination on fertility.

Fifty-four normally cycling, non-lactating mares were given 2 injections (i.m.) of PGF-2 alpha (10 mg) 14 days apart without regard to stage of the oestrous cycle. At 19 days after the first PGF-2 alpha treatment, a single i.m. injection of either hCG (3300 i.u.) or a GnRH-analogue (500 micrograms) was administered. Each mare was inseminated with 100 X 10(6) motile spermatozoa at one of the following frequencies: once only on Day 20; every other day during oestrus or at least on Days 19 and 21; or daily during oestrus or at least on Days 19, 20, 21 and 22. Eighteen control mares received saline injections on Days 0 and 14, and were inseminated either on the 4th day of oestrus or every other day or daily beginning on the 2nd day of oestrus. More (P greater than 0.05) PGF-2 alpha treated mares displayed their 1st day of oestrus on Days 14 to 20 than control mares (80.6 versus 27.8%). During cycle 1, fewer (P greater than 0.05) treated mares became pregnant compared to controls; 38.9, 25.0 and 66.7% for PGF-2 alpha + hCG, PGF-2 alpha + GnRH-A and control mares, respectively. After three cycles, the pregnancy rates for mares inseminated every other day or daily were higher (P less than 0.05) than mares inseminated only once during oestrus (88.9 and 88.2 versus 64.7%).


The bacteriological culture of equine uterine contents, in-vitro sensitivity of organisms isolated and interpretation.

A total of 19 pathogenic bacterial species was isolated from uterine swabs of 498 out of 1539 mares over 4 years. The swabs were taken by 5 veterinary clinicians using 2 different techniques. Bacterial contamination during swabbing was minimized by scrupulous attention to cleansing of the external genitalia and the perineal area, and in the handling of the culture specimen. The most prevalent organisms isolated were beta-haemolytic streptococcus (39%), Escherichia coli (27%) and Klebsiella pneumoniae (7%). Interpretation of microbiological findings correlated well with clinical findings when number of organisms isolated and endometrial cytology were considered. The use of a bacterial transport medium combined with sophisticated culture methods reflects a more accurate picture of the uterine microflora than can be obtained by previous techniques. Streptococci isolated were uniformly sensitive to penicillins. The sensitivity of E. coli and K. pneumoniae towards chloramphenicol, gentamicin and polymyxin was nearly 100%. The selection of an appropriate antibacterial agent depends upon sensitivity, pharmacological action, genital tract status and cost. This study shows that a Gram stain of uterine cytology can be used to diagnose quickly and select an appropriate antibiotic for treatment prior to culture results if sufficient numbers of organisms are present.


Isolation of Klebsiella pneumoniae from the urogenital tract of experimentally infected mares.

K. pneumoniae capsule type 68 infused into the uterus of 4 mares was recovered up to 15 weeks after inoculation. The insertion of a tampon for 10 min was more effective than a swab technique in detecting the organism in the uterus. The clitoral fossa and the urethral orifice when sampled by the swab technique were also found to be infected for a comparable period. K. pneumoniae was isolated from the clitoral specimens more often and more consistently than from either urethral or uterine specimens.


Contagious equine metritis--outbreak of the disease in Kentucky and laboratory methods for diagnosing the disease.

Contagious Equine Metritis (CEM) was initially reported during the 1977 breeding season in England (Crowhurst, 1977) and Ireland (Timoney, Ward & Kelly, 1977. The disease has also been diagnosed in France and Australia (Huges, Bryden & MacDonald, 1978). The first occurrence of CEM in the United States followed the importation or 2 stallions from France late in 1977 which resulted in an outbreak early in the 1978 breeding season (Swerczek, 1978). Mares usually develop clinical signs of CEM 8--10 days after being covered by an infected stallion, when a copious, greyish discharge is seen. Other mares may not show any outward signs of disease, but may have a shortened dioestrous period. Many mares recover spontaneously from the disease, but a small proportion become carriers of the CEM organism. The stallion does not show any clinical signs of disease, but remains a carrier. In this paper we recommend various laboratory procedures for the diagnosis of CEM in mares and stallions.


Endometrial histology and post-partum mares treated with progesterone and synthetic GnRH (AY-24,031).

Foal heat was significantly delayed in 15 Thoroughbred and Quarter-horse mares by 200 mg progesterone in oil from Days 5--14 post partum. Nine of these mares subsequently received daily i.v. injections of 2 mg of a synthetic GnRH preparation (AY-24,031) from Day 2 of the progesterone-delayed oestrus but this treatment did not significantly shorten oestrus or hasten ovulation. Uterine biopsies taken on Day 15 post partum from all the mares showed a mixed endometrial morphology having both oestrous and dioestrous characteristics. There was an increased proliferation of endometrial glands in these animals at the time of ovulation compared to control mares having a normal foal heat.


An analysis of stallion fertility rates (foals born alive) from the breeding documents of the Landgestüt Celle over a 158-year period.

An evaluation of the foaling rate achieved in the Hannoverian breed in Germany between 1815 and 1973 showed that during this period no improvement of the reproductive rate was achieved. The decennial foaling percentage remained within 50--60% except for those decades which included the two World Wars and their aftermaths. The annual foaling percentage remained maximal until the number of mares covered/stallion rose above 80 and it also remained high throughout the reproductive life of the stallion. Only in the oldest stallion (32 years) was there a significant lowering of fertility.


Microphotometric techniques in intravital microcirculatory studies.

Intravital microscopic techniques were developed in order to measure plasma proteins: (1) circulating in the streaming blood of microcirculatory vessels of the exposed rat mesentery, (2) permeating the vessel wall, and (3) moving through the perivascular interstitial tissue. By means of the ultramicrospectrophotometry, the absorbance of proteins containing aromatic amino acids at 280 nm is measured. Absolute amounts of proteins in the range of picograms are measured in a circular measuring field with a diameter of 17 micrometers. Problems of calibration and of unspecific light scattering are discussed. The scanning microfluorometry makes use of the fluorescent labelling of the plasma proteins. Interstitial tissue with a capillary vessel containing labelled proteins is measured at high speed. A motor-driven object stage synchronized with a measuring system uses scanning lines to traverse the tissue. The data are then processed by a computer. In this way we get continuous quantitative information about the dynamics of protein permeability, starting from time zero. The measuring of the fluorescence intensity and the speed of the fluorometric system are further improved by a computerized 10 kHz scanning device.


Inhibition of 2-fluorenamine-induced mutagenesis in Salmonella typhimurium by vitamin A.

Vitamin A alcohol (retinol) completely inhibited the mutagenicity of the carcinogen 2-fluorenamine (2-FA) in Salmonella typhimurium TA98 when the mutagen was activated by liver microsomes from CFN rats. The mutagenicity of 2-FA activated by 9,000Xg rat liver supernatant S9 was inhibited by retinol to a lesser degree. The decline in the number of his+ revertants was not an artifact due to bacterial killing, inasmuch as retinol was not toxic to the bacteria at levels that totally inhibited mutagenesis by 2-FA. Mutagenesis induced by adriamycin, an antibiotic that does not require metabolic activation for mutagenic potential, was unaffected by vitamin A. These results indicate that retinoids inhibit the metabolic activation of some chemical carcinogens to forms that can interact with DNA. Our findings are consistent with the hypothesis that retinoids may exert anticancer activity by inhibiting carcinogen activation, thereby inhibiting tumor induction. In addition to the more widely accepted role of retinoids in modulating the proliferation of epithelially derived neoplasms.


Concentration-dependent mutation by alkylating agents in human lymphoblasts and Salmonella typhimurium: N-methyl-N-nitrosourethane and beta-propiolactone.

The toxic and mutagenic effects of the alkylating agents N-methyl-N-nitrosourethane (MNUT) and beta-propiolactone (BPL) were quantitatively measured in human lymphoblasts and Salmonella typhimurium. Forward mutation to 6-thioguanine resistance was measured in the human lymphoblasts, and forward mutation to 8-azaguanine resistance was measured in the bacterial cells after equigenerational (1.5 doubling times) exposures. In both systems, the induced mutant fraction rose linearly as a function of concentration for BPL and was biphasic for MNUT. The responses of the two assay systems to eight alkylating agents were compared. The exposure of the cells to each alkylating agent was calculated as exposure concentration multiplied by the time of exposure, and allowance was made for the decomposition of the alkylating agents during exposure (integral exposure). Human cells were 2.5--13 times more sensitive than was S. typhimurium to the alkylating agents methyl methanesulfonate, ethyl methanesulfonate, propyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine, methylnitrosourea, and MNUT. S. typhimurium cells were three times more sensitive to butyl methanesulfonate and 25 times more sensitive to BPL than were human cells.


Biochemical markers of central nervous system tumors measured in cerebrospinal fluid and their potential use in diagnosis and patient management: a review.

The concept of tumor markers was reviewed, and the potential uses of markers of central nervous system (CNS) tumors and methods for their evaluation were discussed. Markers examined included lactate dehydrogenase, aspartate aminotransferase, fructose-bisphosphate aldolase, the polyamines, desmosterol, and several other enzymatic, nonenzymatic, and immunologic markers. Data collated from the clinical studies surveyed showed isocitrate dehydrogenase, desmosterol, and the polyamines to have the greatest potential utility in the diagnosis of CNS tumors.


Assay for mutagenicity of bile in Sprague-Dawley rats treated subcutaneously with intestinal carcinogens.

To investigate the mode of action of sc injected intestinal carcinogens, the mutagenicity assay of bile collected from noninbred Sprague-Dawley rats treated sc with carcinogens was conducted in the presence and absence of beta-glucuronidase. The bile samples from rats inoculated with 4-aminobiphenyl were mutagenic for Salmonella typhimurium TA100 only in the presence of beta-glucuronidase, whereas those from the 3,2'-dimethyl-4-aminobiphenyl-treated rats did not require the enzyme for mutagenicity toward strain TA100. On the contrary, the assays with S. typhimurium G46 and TA100 of bile from rats inoculated with 1,2-dimethylhydrazine, azoxymethane, or methylazoxymethanol acetate failed to reveal mutagenicity whether beta-glucuronidase was added or not, though these carcinogens were highly mutagenic for strain G46 in the Salmonella-microsome mutagenicity test and/or in the host-mediated assay.


Correlation between natural and antibody-dependent cell-mediated cytotoxicity against tumor targets in the mouse. II. Characterization of the effector cells.

Direct comparison of the effector cells mediating natural killer (NK) activity against mouse tumor cells and antibody-dependent cell-mediated cytotoxicity (ADCC) against mouse tumor target cells coated with alloantisera indicated that NK cells and K-cells (effector cells mediating ADCC) may belong to the same subpopulation of lymphocytes, but they have a different mechanism of killing. Effector cells mediating NK activity and ADCC were nonadherent, nonphagocytic Fc receptor-bearing cells that sediment at 3.5-4.5 mm/hour. Treatment with anti-Thy 1.2 serum in the absence of complement resulted in an increase of NK activity, whereas this treatment caused a substantial loss in ADCC. Both NK activity and ADCC were equally sensitive to the in vivo or in vitro effects of X-irridiation. In vivo inoculations of high doses of hydrocortisone resulted in a reduction of NK activity, but ADCC was not affected. NK cells were trypsin-sensitive, with a profound decrease in the cytolytic activity being observed in a 4-hour 51Cr release assay. The activity, however, could be recovered after overnight incubation at 37 degrees C. Trypsin treatment did not inhibit ADCC as measured by the 18-hour assay.


Control of protein synthesis in Escherichia coli: control of bacteriophage Q beta coat protein synthesis after energy source shift-down.

Escherichia coli Q13 was infected with bacteriophage Q beta and subjected to energy source shift-down (from glucose-minimal to succinate-minimal medium) 20 min after infection. Production of progeny phage was about fourfold slower in down-shifted cultures than in the cultures in glucose medium. Shift-down did not affect the rate of phage RNA replication, as measured by the rate of incorporation of [14C]uracil in the presence of rifampin, with appropriate correction for the reduced entry of exogenous uracil into the UTP pool. Phage coat protein synthesis was three- to sixfold slower in down-shifted cells than in exponentially growing cells, as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The polypeptide chain propagation rate in infected cells was unaffected by the down-shift. Thus, the reduced production of progeny phage in down-shifted cells appears to result from control of phage protein synthesis at the level of initiation of translation. The reduction in the rate of Q beta coat protein synthesis is comparable to the previously described reduction in the rate of synthesis of total E. coli protein and of beta-galactosidase, implying that the mechanism which inhibits translation in down-shifted cells is neither messenger specific nor specific for 5' proximal cistrons. The intracellular ATP pool size was nearly constant after shift-down; general energy depletion is thus not a predominant factor. The GTP pool, by contrast, declined by about 40%. Also, ppGpp did not accumulate in down-shifted, infected cells in the presence of rifampin, indicating that ppGpp is not the primary effector of this translational inhibition.