Electron microscope comparison of freeze-substitution and conventional chemical fixation of undecalificied human dentin.

Within the stated limits of cell fine structure preservation and within the observed anatomical limits specified in the Results and Discussion sections, a freeze-substitution method using an ethylene glycol-Hank's solution eutectic mixture with a glutaraldehyde additive can be used to effectively prepare undecalcified human dentin for electron microscopy. The ultrastructual appearance of the odontoblast cell body and the odontoblastic process subjected to freeze-substitution differs from that seen with conventional chemical fixation. Artifacts produced by freeze-substitution differ in appearance and frequency of occurrence from those produced by glutaraldehyde-osmium tetroxide sequential double fixation. The cellular component of dentin shows greater structural preservation of protein when it is subjected to freeze-substitution that when it is prepared by conventional chemical fixation. The absence of ice crystal defects in the odontoblastic process in calcified dentin and the presence of ice crystal defects in the odontoblast cell body suggest that intracellular water in the odontoblastic process in the calcified dentin may exist in a more highly structured state than intracellular water in the odontoblast cell body. If intracellular water exists in a more highly structured state in the odontoblastic process of the calcified dentin than in the cell body, the ratio of protein molecules to cytoplasmic volume may be greater in the odontoblastic process than in the cell body. After glutaraldehyde-osmium tetroxide sequential double fixation, the use of graded alcohol dehydration obtained cell fine structure preservation and artifact control superior to that obtained by use of ethylene glycol cryodehydration. Further refinements of the freeze-substitution technique, as it applies to the preparation of undecalcified human dentin, are necessary to increase the amount of cellular preservation, to decrease the number of ice crystal artifacts, and to improve the overall quality of cell fine structure preservation.


The Pupil Evaluation Inventory. A sociometric technique for assessing children's social behavior.

The Pupil Evaluation Inventory was developed to assess peer ratings of the behavior of male and female children in grades one through nine. Three homogeneous and stable factors emerged from a factor analyss: Aggression, Withdrawal and Likeability. High interrater agreement between male and female raters, stability of factorial structure, high internal consistency, and moderate concurrent validity were found across sex and grade levels. Test-retest reliability was high for a separate sample of third and sixth graders. There was a tendency for higher internal consistency and teacher-peer correlations for the Aggression factor.


Adhesion of orthodontic cements to human enamel.

The tensile bonding characteristics of five orthodontic cements to etched human enamel with and without a silane primer after storage for 1, 7, and 30 days in artificial saliva at 37 C were compared. The scatter of the data was probably due to the wide variation of surface morphology of etched human enamel. Cement L, a composite resin cement, was significantly stronger than the other cements tested. Cement D, a polycarboxylate cement, was significantly the weakest cement tested. Cements U, O, and N-B were of relatively equal bond strengths. Of the direct-bonding systems commercially available, the N-B system had the fastest setting time. The silane primer used in the research decreased the bond strength of cement O; however, it significantly increased the bond strength of cement L. Storage in artificial saliva at 37 C for 30 days decreased the mean bond strengths of most of the orthodontic cements with and without a silane primer. The exceptions were cement N-B without a silane primer and cements O and D with silane primer.


Caffeine in the "sundown syndrome." Report of negative results.

This paper reports the results of a double blind study in patients with senile dementia to determine if the quality and quantity of sleep could be changed with various amounts of caffeine. Twelve patients with dementia were studied in a nursing home setting. Patients were medication free for a month prior to the study. Four treatments were given in a double blind technique. These included an uncaffeinated liquid and coffee with various amounts of caffeine. Measurements checked included sleep induction time, quality of sleep, total length of sleep, time awake during the night, and a global rating. No significant differences were noted between the noncaffeinated placebo and the coffee containing various amounts of caffeine.


The stereotype of "old." A review and alternative approach.

Within the literature, a negative stereotype of "old" has been emphasized which, it has been argued, is important for self-concept in late life. This paper questions the validity of this argument and presents an alternative model more congruent with extant data. Forty-seven reports of research on stereotypes of old age were analyzed. It was found that 21 studies utilized older persons in the sample, and half of these were based on institutionalized or indigent aged. A positive stereotype of old age was reported in several studies. Thus, the assumption that the aged accept a negative stereotype of old age may not be valid. An alternative theoretical model is presented. From the framework of cognitive dissonance theory, it is argued that the acceptance of a negative or positive stereotype by the aged is related to objective indicators of old age, the subjective definition of self, and self-concept.


A bibliography of doctoral dissertations on aging from American institutions of higher learning, 1973-1975.

This bibliography acts as the fifth supplement to the original title which covered 1934-1969. The supplements will include all titles of earlier years which were found after the original bibliography was published, Journal of Gerontology, 1971, 26, 391-422. Due to the nature of bibliographic control in regard to doctoral disserations, each supplement will try to cover the academic year rather than the physical year. This means that a dissertation issued in 1970 may be either in the original bibliography or in the supplements. The arrangement of the supplement is similar to the original bibliography.


Infusion of donor lymphocytes into stable canine radiation chimeras: implications for mechanism of transplantation tolerance.

Canine radiation chimeras were used to investigate further mechanism(s) responsible for maintaining the stable chimeric state. Chimeras were studied 7 to 46 months after 1200 R total body irradiation and transplantation of marrow from a littermate donor matched at the major histocompatibility complex. An attempt was made to perturb the stable chimeric state by infusion of large numbers (0.6 to 13.7 x 10(8)/kg) of donor peripheral blood lymphocytes into each respective chimera. Two groups were studied: donors in Group A were normal; donors in Group B had been specifically sensitized against minor histocompatibility antigens of the chimera by repeated skin grafts. None of the nine chimeras in Group A developed significant clinical or histologic evidence of graft-vs-host disease (GVHD) after donor lymphocyte infusion. Eight of the 12 chimeras in Group B, however, developed GVHD which was transient in three and fatal in five. The results in Group A are not consistent with classical theories of tolerance, i.e., elimination or inactivation of potentially reactive cell clones, but suggest the presence of an active mechanism suppressing recognition of host antigens by the infused donor lymphocytes and development of GVHD. The results in Group B indicate that this mechanism can be overcome by infusion of sensitized donor cells. In an attempt to elucidate the nature of this postulated active mechanism, the cytotoxicity of donor lymphocytes for fibroblasts of the chimera and the presence or absence of serum-blocking factors were assessed in vitro by using a cellular inhibition (CI) assay. The presence of serum-blocking factors did not protect against the development of significant GVHD in two chimeras (fatal in one). GVHD did not occur in four other chimeras after infusion of cytotoxic donor lymphocytes despite the absence of serum-blocking factors. These and previous results suggest that serum-blocking factors are not the mechanisms suppressing the development of GVHD in canine radiation chimeras, and raise the possibility that a suppressor cell population may be responsible for preventing GVHD.


Effect of lipopolysaccharide on the induction of tolerance to polymerized flagellin.

The effect of bacterial lipopolysaccharide (LPS) on the induction of tolerance to the T-independent polymerized flagellar protein (POL) of Salmonella adelaide strain SW1338 was studied in vitro. In contrast to published results with T-dependent antigens, LPS failed to prevent or reverse tolerance induction to POL under conditions in which tolerance was reversible by other means. Moreover, the addition of high doses of LPS to slightly supra-immunogenic concentrations of POL augmented-tolerance induction. These results suggest that the mitogenic properties of LPS are insufficient to convert a tolerogenic dose of POL into an immunogenic one and, therefore, that LPS may act only on T-dependent B cell responses. Since both POL (1338) and LPS are T-independent, mitogenic and so-called "polyclonal B cell activators," these data have implications for signal discrimination in the immune response.


Preparation and effects of an anti-B cell serum.

An heterologous antiserum specific for bone marrow-derived cells (B cells) was prepared by immunizing rabbits with lymph node cells from nude mice. After absorption with mouse red blood and thymus cells, the antiserum killed a population of cells from various lymphoid organs and the cytotoxic effects were inversely related to those of anti-theta antibody. When bone marrow or spleen cells were treated with the antiserum and guinea pig complement before transfer into irradiated mice, the number of plaque-forming cells was greatly reduced in the spleen of the recipient. Pretreatment of thymus cells with the antiserum in a similar way resulted in no inhibition of hemolytic plaque. When spleen cells from mice previously immunized with sheep red blood cells were treated with the antiserum and complement, the formation of hemolytic plaque was not affected. These findings indicated that the antiserum was specific for B cells and that the number of antigenic determinants on B cells to which the antiserum reacted decreases during differentiation into antibody-forming cells.


An in vitro assay for T cell immunity to malaria in mice.

After infection with a nonlethal strain of murine malaria (17XNL Plasmodium berghei yoelli), BALB/c mice are then resistant to a lethal strain (17XL P.b. yoelli). BALB/c mice were infected with 17XNL, anc challenged 3 weeks later, after clearing their parasitemias, with 17XL. Three weeks thereafter, spleen cells from such immune animals were used to define an early peaking T-dependent (anti-theta sensitive) antigen-specific proliferative response when incubated in vitro with 17XL infected RBC, or a saline soluble 17XL antigen preparation. T dependent responsiveness of spleen cells from uninoculated control animals to the 17XL antigen preparation was also observed, but demonstrated a much different (delayed) kinetics from that observed with immune cells.


Local immunization in the mammary glands of the rabbit.

The effects of a local immunization with bovine serum albumin in the left mammary glands of the rabbit have been compared with those of an intramuscular (i.m.) immunization. The ability of several tissues to synthesize antibodies was studied in vitro with or without in vitro antigenic stimulation, and the antibody class in the plasmocytes of these tissues was determined by immunofluorescence. After i.m. immunization, the serum antibodies synthesized by the spleen and the lymph nodes pass into the milk by transudation; there is no antibody synthesis in the mammary glands. After immunization in the left mammary glands, there is antibody synthesis in the left mammary glands and also in the spleen and lymph nodes. In the mammary glands in the antibodies belong essentially to the IgG class and are synthesized by the plasmocytes that infiltrate the granulation tissue around the injection sites. The fragments of the immunized glands are capable of an in vitro secondary response analogous to that made by the spleen and lymph nodes. Thus the local immunization of the mammary glands does not stimulate the secretory immunologic system but elicits an antibody synthesis in the granuloma as in any other tissue. This local immunization also provokes a traffic of sensitized cells to the same lymphoid tissues as an i.m. immunization does.


An enzyme-linked procedure for the detection and estimation of surface receptors on cells.

An enzyme immunoassay procedure has been developed for the visualization and estimation of lymphocyte surface receptors. beta-Galactosidase (beta-gal'ase) was covalently linked to sheep anti-rabbit immunoglobulin (SARIg), to ovalbumin (OA), and to adenosine (A). Exposure of rabbit peripheral lymphocytes to SARIg-beta-gal'ase and subsequent incubation with the fluorogenic substrate fluorescein-beta-digalactopyranoside allowed visualization of B cells by fluorescence microscopy. Treatment with each of the above beta-gal'ase conjugates and incubation with another fluorogenic substrate, 4-methyl-beta-D-umbelliferylgalactopyranoside, made possible the estimation of the various receptors by spectro fluorimetry. Procedures used for enrichment of T and B cell populations could be monitored. Among the findings was that immunoglobulin-bearing cells (presumably B cells) formed rosettes with sheep erythrocytes. The quantitative procedure was used to study lymphocyte population changes during immunization with an A-O A conjugate. An increase in the binding of A-beta-gal'ase, SARIg-beta-gal'ase, and OA-beta-gal'ase by peripheral lymphocytes occurred repeatedly 6 to 8 days after immunization but lasted only a few days despite a continued high circulating antibody titer. These results are consistent with the possibility that immunization induces migration of lymphocytes into the circulation from bone marrow and/or thymus.


Specific removal of bovine serum albumin (BSA) antibodies in vivo by extracorporeal circulation over BSA immobilized on nylon microcapsules.

Studies were undertaken to determine whether BSA, once immobilized on activated nylon microspheres, would be capable of specifically removing circulating BSA antibody in vitro and in vivo in an extracorporeal circulation system in dogs. Nylon microspheres were prepared and, after gentle hydrolysis and glutaraldehyde treatment, demonstrated a retention of up to 34.5 mg of BSA. In vitro studies showed that BSA immobilized on microspheres removed a significant percentage of BSA-binding activity. For in vivo studies, an extracorporeal circulation system was established and mongrel dogs were then injected with anti-BSA and anti-HSA antibodies. After an equilibration period, BSA microspheres were introduced into the extracorporeal circulation system. After the insertion of BSA microcapsules, serum exhibited a sharp reduction in BSA binding over the next 15 min, with a more gradual diminution over the ensuing 60 to 90 min. There was no significant reduction in anti-HSA binding over the same time frame. This effect could not be attributed to release of BSA from the microspheres since no 125I-BSA was detected in the serum or organs of the dogs at the conclusion of the experiments. After extracorporeal circulation over nylon microspheres, there were only minimal changes in the host's hematocrit or leukocyte counts and no significant thrombotic material or cellular debris was recoverable on the capsules. These data suggest that antigen immobilized on nylon microspheres may specifically withdraw circulating antibodies in vivo with minimal release of its antigenic material and little alteration in the host's hematologic status.


Trypsin increases in vitro antibody synthesis and substitutes for helper T cells.

Trypsin, a neutral protease, enhanced the direct plaque response of T cell-suffiecient mouse spleen cell cultures to sheep erythrocytes (SRBC) and significantly increased the number of spontaneous PFC against SRBC in cultures without antigen. Moreover, trypsin proved to be able to substitute for T cells in nu/nu spleen cell cultures stimulated with SRBC. Its restorative capacity in this type of response was comparable to the one of lipopolysaccharide. Restoration of antibody synthesis in T cell-deprived cultures could not be explained by enzymatic alteration of SRBC. The data are discussed in terms of a possible role of hydrolytic enzymes released by accessory cells during the induction of an antibody response.


The effects of antigen dose and adjuvant on the antibody response; amplification of restricted B cell clones.

Anti-DNP antibody production in inbred strain 2 guinea pigs immunized with chemically defined DNP-oligolysines was enhanced by increasing the antigen dose or employing more potent adjuvants. However, the increase in antibody titer was not accompanied by an increase in antibody heterogeneity. Only a small number of anti-DNP antibody-producing B lymphocyte clones were triggered to produce antibody, regardless of the antigen dose or the adjuvant used for immunization or the resulting specific antibody titer. This restricted response occurred despirte the capacity of these animals to synthesize a large number of distinct anti-DNP antibodies and of DNP-oligolysines to bind all these antibodies. These observations are inconsistent with the hypothesis that adjuvant and increased antigen dose enhance antibody titer by recruitment of more diverse precursor B cells (clonal recruitment), but support the hypothesis that adjuvant and increased antigen dose act by enhancing the expansion of a restricted few B lymphocyte clones (clonal expansion).


Augmentation of cell-mediated cytotoxicity against syngeneic Gross virus-induced lymphoma in rats by phytohemagglutinin and endotoxin.

Normal W/Fu rat spleen cells cultured for 1 day with mitogenic concentrations of phytohemagglutinin (PHA) or with a wide range of concentrations of endotoxin (LPS) exerted cytotoxic activity against the syngeneic Gross virus-induced lymphoma, (C58NT)D, and also against other tumor cells in a 4-hr 51Cr release assay. This activity did not involve release of detectable lymphotoxins, nor did it require the presence of additional mitogen in the media during the cytotoxicity assay. The cytotoxic activity induced by PHA was dependent on the presence of T cells while the activity induced by LPS was not dependent on T cells and appeared to require the presence of macrophages. Both PHA and LPS also augmented the cytotoxic activity of spleen cells immune against (C58NT)D tumor cells. With submitogenic concentrations of PHA, only specific cytotoxicity against (C58NT)D cells was augmented. In contrast, LPS and mitogenic concentrations of PHA caused nonspecific augmentation. Mitogenic concentrations of PHA and LPS also augmented the antibody-dependent cytotoxicity of normal W/Fu rat spleen cells against (C58NT)D cells in the presence of syngeneic anti-serum.


Enzyme-linked immunoassay: conjugation of the Fab' fragment of rabbit IgG with beta-D-galactosidase from E. coli and its use for immunoassay.

1. A method for the conjugation of the Fab' fragment of rabbit IgG with beta-D-galactosidase from Escherichia coli is described. The method consists of two main steps: treatment of the Fab' fragments containing sulfhydryl groups with excess N,N'-o-phenylenedimaleimide, to introduce maleimide residues into the fragments, and then incubation of the dimaleimide-treated Fab' fragments with beta-D-galactosidase, which also contains sulfhydryl groups, to form the rabbit Fab'-beta-D-galactosidase complex. More than 90% of the enzyme used can be converted to the Fab'-enzyme complex, and the complex is readily separated from free Fab' fragments by chromatography on a Sepharose 6B column. 2. The application of the rabbit Fab'-beta-D-galactosidase complex for immunoassay of macromolecular antigens is shown by measuring human IgG by the sandwich method. The rabbit (anti-human IgG) IgG-coupled Sepharose 4B is incubated with human IgG and then with the rabbit (anti-human IgG) Fab'-enzyme complex, and the enzyme activity bound to the Sepharose is measured. In this way it is possible to determine as little as 0.3 fmoles of human IgG.


Macrophage requirement for the in vitro response to TNP Ficoll: a thymic independent antigen.

The in vitro antibody-forming cell response of mouse spleen cells to the thymic independent synthetic polymer, TNP-Ficoll, was found to require the presence of either macrophages or 2-mercaptoethanol. The TNP-Ficoll response and that to the thymic dependent antigen, sheep erythrocytes, demonstrated the same degree of macrophage dependence. However, macrophage-depleted spleen cells which did not produce plaque-forming cells responded normally to T and B cell mitogens. Comparison of the antibody-forming cell response of macrophage-depleted spleen cells in the presence and absence of 2-mercaptoethanol indicated that either macrophages function 10 to 100 times more efficiently in its presence or that 2-mercaptoethanol partially replaces the function of macrophages.


Effects of BCG on lymphocyte trapping.

The effects of Bacillus-Calmette Guerin (BCG) administration upon lymphocyte traffic was studied in BALB/cJ mice. Intravenous or subcutaneous injection of BCG resulted in increased localization (trapping) of 51Cr-labeled syngeneic lymphocytes in the spleen or draining nodes. BCG-induced splenic trapping was biphasic, occurring 1 to 2 days after BCG injection, and reappearing 3 weeks later. Trapping in draining lymph nodes persisted and increased during the 24 days of study. These results are in contrast to those obtained with SRBC, where trapping was evident only within the first few days of antigen injection. Additional studies revealed that prior injection of BCG influencdd the ensuing magnitude of SRBC-induced trapping. Intravenous administration of BCG suppressed SRBC-induced splenic trapping; both intravenous and subcutaneous injection of BCG enhanced trapping to SRBC in the draining lymph nodes. These studies suggest that one mechanism for potentiation of immune responses by BCG may operate via BCG's effects upon regulation of lymphocyte traffic to the lymphoid tissues.


Antibodies to the triplet codons AAA, AAC, and AUG: reactions with nucleic acids.

Antibodies specific for the trinucleotide codons AAA, AUG, and AAC were examined for their reactions with nucleic acids. Anti-AUG and anti-AAC precipitated denatured DNA. Anti-AAA did not, and moreover, the binding of a tritiated AAA derivative to anti-AAA was not inhibited by denatured DNA. Radioligand-binding studies showed that anti-AAA was highly specific for the triplet sequence, some cross-reactions occurring with di-A and tetra-A but little with A and poly(A). The anti-codons did not precipitate whole yeast RNA, but binding could be demonstrated with Escherichia coli 3H-rRNA. Anti-AAC and anti-AUG (but not anti-AAA) bound E. coli 14C-tRNA. Anti-AUG was found to inhibit protein synthesis in an in vitro system in which rabbit reticulocyte mRNA was being translated. Inhibition was abolished by absorption of the antibody with AUG-RSA. The results of these and previous experiments (reference 1) are interpreted to indicate that antibodies can recognize trinucleotide sequences but not with absolute specificity, and it is suggested that antibodies to longer nucleotide sequences might show specificity comparable to that shown by antibodies to polysaccharide and peptide sequences.


Structural features and biologic properties of fragments obtained by limited proteolysis of C3.

Limited proteolysis of the third component of human complement (C3) was performed by using trypsin and streptococcal proteinase and the digests were analyzed for biologic activity. Incubation of C3 with trypsin for 1 min yielded a peptide with smooth muscle-contracting activity but no chemotactic activity, whereas the digest obtained after 15 min of incubation had only chemotactic activity. The conversion of muscle contracting to chemotactic activity could be correlated with the time course of trypsin hydrolysis. Hydrolysis of C3 with streptococcal proteinase gave a digest demonstrating only chemotactic activity. Each digest was resolved on a Sephadex G-100 column and the fractions containing biologic activities were characterized. The amino acid composition of the trypsin fragments, despite having different biologic activities, was remarkably similar, although differences in NH2-terminal amino acids were demonstrable. The fragments obtained by digestion of C3 with the streptococcal proteinase had an amino acid composition different from the trypsin fragments and displayed marked heterogeneity of NH2-terminal residues. These results suggest that slight alterations in the primary structure of C3 fragments may yield significant changes in their biologic activities and that the structural requirements for chemotactic activity are not confined to a single peptide species.


Electrophoretic mobility of human lymphocytes purified by nylon wool columns and spontaneous sheep red blood cells rosetting techniques correlation with immunofluorescence.

Cell electrophoresis allows separation of normal human lymphocytes into two principal groups which are a function of their relative rates of migration. In 42 healthy adults, 19.9% of the lymphocytes have a slower migration rate, and 80.1%, a faster migration rate than the reference speed (1 mum - sec-1 - cm). Two methods are used for the selection of the lymphocytic populations: spontaneous rosetting with sheeps red blood cells, a property of T-lymphocytes, and adherence to nylon wool columns, which preferentially selects B-lymphocytes. The cells which do not form spontaneous rosettes, but adhere to nylon wool columns show mainly slow migration. Cells which do not adhere to nylon columns show a faster migration rate. These findings affirm the T-nature of the rapidly migrating lymphocytes, and the B-nature of the slow-migrating lymphocytes. Results by the immunofluorescence technique confirm this.


Failure of Farr test in detecting IgM response to dinitrophenyl in mice.

In mouse serum the ammonium sulphate technique does not detect the immune response to the haptenic determinant DNP on polysaccharide, nor the early stage of the primary response to DNP on protein. Specific anti-DNP antibodies are easily detected, in the same sera, by the phage neutralization technique. This failure of the Farr test seems to be related to its inability to measure adequately mouse anti-DNP 19S antibodies.


A simplified procedure for in vitro immunization of dispersed spleen cell cultures.

Dispersed spleen cell suspensions from normal mice were immunized with sheep erythrocytes in flat bottom vial tubes containing a relatively small amount of tissue culture medium fortified with a 'nutrient cocktail'. The magnitude of the number of antibody plaque forming cells appearing in such tube cultures was equivalent or greater than that obtained in Marbrook vessels in the Mishell--Dutton system. Omission of the nutrient cocktail on the day of culture initiation, or the use of round bottom vials, resulted in much lower PFC responses.


Use of 125I-labelled albumin for the detection and measurement of delayed-hypersensitivity reactions in the mouse.

Accumulation of 125I-labelled albumin in the mouse hind foot has been used to measure reactions of delayed hypersensitivity in the mouse. The assay is technically simple and permits use of groups of 10 or more animals. Its sensitivity and reproducibility have been demonstrated by comparing sensitized with non-sensitized animals in two antigen systems (P.P.D. and an extract of Trypanosoma cruzi).


The role of Langerhans cells in allergic contact hypersensitivity. A review of findings in man and guinea pigs.

Evidence in favor of a role for Langerhans cells in contact allergic hypersensitivity reactions has been reviewed. This includes mononuclear cell to Langerhans cell apposition and damage to some Langerhans cells at sites of specific challenge to a variety of contact allergens. Such apposition occurs in actively sensitized patients and guinea pigs and in passively sensitized guinea pigs. In addition, in passively sensitized guinea pigs Langerhans cells circulate in dermal vessels resembling lymphatics and are much increased in the dermis after challenge with the contact allergen. These observations, together with the existing knowledge that Langerhans cells occur in the lymph nodes and thymus, suggest that these cells may be involved not only in contact allergic reactions but also in other immunologic reactions, particularly in cell-mediated reactions in the skin.


Genesis of the sweat:plasma urea concentration gradient.

Experiments with 14C-labeled urea in human volunteers show that urea is sequestered in the epidermis, where it turns over more slowly than in general body water. Sequestered urea, presumed to be concentrated through insensible evaporation of water, is the source of the excess urea found in sweat. Physiologic and clinical implications of the existence of this urea pool are discussed.


Preservation of specific fluorescence by sealing with nail polish.

Semipermanent mounting media and postfixation of immunofluorescence (IF) slides in alcohol have been effective in preserving specific fluorescence (SF). In the present study the efficacy of such mounting was compared with a simpler technique of sealing the routinely mounted IF slides with nail polish. Frozen sections of skin lesions of systemic lupus erythematosus and lichen planus, and patients' sera known to have pemphigus or pemphigoid antibodies were used for IF procedures. SF was equally detectable with both techniques for over 8 months. Control slides similarly processed but not sealed lost most of their SF within a few weeks.


Experimental model of severe renal hypertension.

A simple technique is described for producing severe reproducible renal hypertension in the rat. Total ligation of the aorta between the renal arteries and just below the origin of the superior mesenteric artery resulted in sustained systolic and diastolic pressures in 90 per cent of 170 rats studied. Arterial pressure is then measured in the conscious unrestrained rat through a carotid cannula inserted no more than 48 hours before measurements are made. The mean arterial pressure increases to a peak of 180 mm. Hg at day 5 and then remains at a plateau of 160 mm. Hg through the 40 days of the study. Plasma renin increases to a peak at 5 days but returns to baseline at 30 days despite the persistence of severe hypertension. Infarction of the left kidney below the aortic constriction results in no increase in pressure or plasma renin. Infarctions of the right kidney by emboli originating from the indwelling carotid cannula are associated with greater increases in blood pressure and plasma renin than the standard preparation. Prolonged carotid cannulation must be avoided in order to prevent such emboli. This simple technique for producing renal hypertension allows studies on the pathogenesis of hypertension with an excellent degree of reproducibility and reliability.


Determinants of variation between Fick and indicator dilution estimates of cardiac output during diagnostic catheterization. Fick vs. dye cardiac outputs.

Simultaneous Fick and duplicate dye cardiac outputs were done in 105 patients with various cardiovascular diseases during routine cardiac catheterization. Dye was injected into the pulmonary artery and sampled from the brachial artery. Nineteen patients had mitral and/or aortic valvular regurgitation. Eighty-four per cent of the duplicate dye cardiac outputs agreed within 10 per cent variation from the line of identity, and 98 per cent were within 25 per cent. There was no systematic difference between the Fick and dye methods. Seventy-five per cent agree within 20 per cent variation from the line of identity. However, individual variation ranged from -27 to +58 per cent. There was, also, no systematic difference between Fick and dye methods either with low cardiac index or valvular regurgitation. Variation between the two methods was less with low cardiac index and greater with higher cardiac index. The variation was not increased in the presence of valvular regurgitation. The variation in the two methods could partly be explained by errors in the measurement of arteriovenous oxygen difference and oxygen consumption. When the injection is made into the pulmonary artery and sampled from the brachial artery, dye outputs are valid irrespective of the level of resting cardiac index and valvular regurgitation as long as there are enough points to draw a straight line from semilogarithmic trace of the descending limb.


Plasma post-heparin lipolytic activity and triglyceride clearance in uremic and hemodialysis patients and renal allograft recipients.

In order to study mechanisms in the pathogenesis of hypertriglyceridemia in uremia, maintenance hemodialysis, and post-renal transplantation, plasma post-heparin lipolytic acitivity was measured and the kinetics of triglyceride removal were determined during infusions of triglyceride in patients from each of these groups and in healthy control subjects. In addition, plasma lipolytic activity was measured both during the course of a single hemodialysis treatment and in response to daily hemodialysis over a five-day period. The mean serum triglyceride level was significantly elevated and the mean plasma post-heparin lipolytic activity significantly reduced in all three groups. Post-heparin lipolytic activity in transplant recipients with a normal serum creatinine concentration was not significantly different from that in control subjects. Those transplant recipients with mildly impaired graft function had levels of post-heparin lipolytic activity comparable to those in patients with end-stage renal failure. Triglyceride clearance was significantly reduced in both the transplant recipients and in the uremic patients. During a single hemodialysis treatment with systemic heparinization plasma lipolytic activity decreased after the first hour. With daily hemodialysis, predialysis post-heparin lipolytic activity progressively declined after the second day. It is concluded that reduced post-heparin lipolytic activity and decreased triglyceride clearance contribute to the hypertriglyceridemia seen not only in uremic patients and in patients on maintenance hemodialysis but also in renal allograft recipients. Diminished lipolytic activity in hemodialysis patients may be in part due to heparin-induced depletion.


Absorption of cholesterol by the gallbladder.

To study whether cholesterol is absorbed by the gallbladder, we instilled from 1 to 300 nmoles of [4-14C]cholesterol dissolved in 1 ml of guinea pig bile into the in situ guinea pig gallbladder. The bile used in these experiments contained 7 mumole/ml bile acid, 27 nmole/ml lecithin, and 8 nmol/ml cholesterol. To this bile, we added the radioactive cholesterol, from 0 to 1 mumole/ml egg lecithin, and 100 mug/ml of bromosulfophthalein, a nonabsorbable marker. After 1 nmole [4-14C]cholesterol was instilled in bile without added lecithin, 77 +/- 8% of the radioactivity was demonstrated to be in the gallbladder wall 6 hours later. The proportion of cholesterol absorbed by the gallbladder decreased as the concentration of added lecithin or bile salts was increased. Radioautography showed radioactivity in the mucosa, and subcellular fractionation of homogenized cells by centrifugation showed cholesterol in the mitochondrial (23 +/- 4%) and microsomal (18 +/- 4%) fractions. Studies on specific activity suggested that there was net absorption of cholesterol and not merely an exchange of cholesterol in the contents for cholesterol in the wall. This study presents evidence that significant quantities of cholesterol but not cholesterol ester can be absorbed by the guinea pig gallbladder. We also found that the absorbed cholesterol can be converted to cholesterol ester and the relevance of these findings to cholesterosis in man are discussed.


The pituitary response to exogenous luteinizing hormone releasing factor in steroid-treated gonadectomized rats.

Rats gonadectomized 1-2 months previously were anaesthetized with sodium pentobarbitone and 50 ng/100 g body weight of a synthetic decapeptide gonadotrophin releasing factor (LH-RF) injected intravenously. Palsma concentrations of LH and FSH were determined by radioimmunoassay in samples taken before and at intervals up to 60 min after injection of LH-RF. The pituitary response was evaluated by determining the maximal increment in plasma gonadotrophin concentrations and by estimating the area under the plasma gonadotrophin concentration curves. In both males and females the pituitary response was increased in animals given 20 mug oestradiol benzoate 3 days earlier. Progesterone (2-5 mg) had no effect on the response measured 4 h later in oil-treated rats, male or female. In oestrogen-primed rats progesterone administration produced a significantly increased response in females that was not seen if sodium pentobarbitone was given at the time of progesterone injection. In oestrogen-primed males progesterone produced some increase in sensitivity but less than was seen in females. Both in males and in females that had received androgen on day 4 of postnatal life sodium pentobarbitone had no effect on the responses of oestrogen plus progesterone-treated rats to LH-RF. When two injections of LH-RF were given 60 min apart, the second response was greater than the first in animals, both male and female, that had been primed with oestrogen. The second response was no greater than the first in oil-treated females. The results suggest that oestrogen can increase pituitary sensitivity of LH-RF in both male and female rats and that LH-RF itself can increase pituitary sensitivity to a second injection of LH-RF in both male and female rats if they have received oestrogen. It is suggested that the differences between the pituitary responses of females and males after oestrogen plus progesterone treatment and the major differences in gonadotrophin secretion reported previously (Brown-Grant, 1974) may be accounted for on the basis of there being a relatively slight increase in endogenous LH-RF secretion with a consequent marked rise in pituitary responsiveness in female but not in male rats.


The formation of the gonadal ridge in Xenopus laevis. III. The behaviour of isolated primordial germ cells in vitro.

Previous studies have described the morphology, including the ultrastructure, of primordial germ cells (PGCs), and the cells with which they associate to form the gonadal ridge, in Xenopus laevis. In order to test their capacity for active movement we have studied single, isolated PGCs in vitro. Time-lapse studies of these cells reveal that they are motile, using broad cytoplasmic processes. The fact that these cells are very large and easy to manipulate in vitro makes them an attractive subject of study, particularly with respect to the mechanism of their movement and the surface phenomena which guide them to the site of the gonadal ridge.


The nature and distribution of serologically detectable alloantigens on the preimplantation mouse embryo.

The nature and distribution of surface alloantigens on preimplantation mouse embryos has been examined by immunofluorescence. Non-H-2 alloantigens were detected at all stages examined, from the 2-cell to the 4 1/2-day blastocyst. Cleaving blastomeres, inner cell mass cells and cells of the primary trophectoderm were all positive. In F1 embryos maternal non-H-2 alloantigens were detectable at all stages, whereas paternal antigens first became evident at the 6- to 8-cell stage. No convincing evidence of the presence of alloantigens associated with the H-2 haplotype was found at any stage or on any cell type, suggesting that if these antigens are present they are in low quantity or are masked.


The behavior of skin grafts incompatible with respect to skin alloantigens on mice rendered tolerant at birth with lymphoid cells.

It has been reported that lethally irradiated adult B6 mice restored with (A X B6) hemopoietic cells subsequently reject adult A-strain skin grafts because they are not tolerant of A-strain skin-specific (Sk) antigens. This thesis has been confirmed by a series of experiments conducted on neonatally treated animals. Thus sublethally irradiated neonatal B6 mice, inoculated with (A X B6) lymphoid cells, permanently accept these cells while subsequently rejecting adult strain A skin grafts. Further evidence that the destruction of these grafts results from the reaction of the host to Sk antigens, is provided by the fact that similarly treated recipients often permanently accept neonatal A-strain skin. Such grafts usually induce tolerance of adult A-strain skin grafts.


Trypanosoma cruzi: mechanism of entry and intracellular fate in mammalian cells.

The mode of entry and intracellular fate of epimastigotes and trypomastigotes of Trypanosoma cruzi in cultured cells was studied. Electron microscopic observations indicated the uptake by phagocytosis of both forms into mouse peritoneal macrophages and of trypomastigotes and transition forms into other cultured cell types. In each instance the organisms were initially surrounded by a plasma membrane-derived phagosome. Trypsin and chymotrypsin treatment of the macrophages completely abolished attachment and ingestion of both forms, indicating that protease-sensitive structures on the macrophage plasma membrane mediate ingestion. The macrophage Fc or C3b receptors were not essential for uptake of T. cruzi in the conditions used. Cytochalasin B inhibited ingestion but not the attachment of both forms by macrophages. Epimastigotes were not taken up by HeLa, L cells, and calf embryo fibroblasts. In macrophages, epimastigotes were killed and digested within phagolysosomes. In contrast, trypomastigotes and transition forms escaped from the phagocytic vacuole and then multiplied in the cytoplasmic matrix. Amastigotes released from infected cells exhibited properties similar to those of trypomastigotes and were able to enter all cell types studied and multiply intracellularly.


Spleen cells from animals tolerant to a thymus-dependent antigen can be activated by lipopolysaccharide to synthesize antibodies against the tolerogen.

Immunological tolerance was induced in adult mice by the injection of 5 mg of deaggregated hapten-protein conjugate. The tolerant state was confirmed 4-19 days later by the failure of such animals to mount an immune response against an aggregated form of the same thymus-dependent hapten-protein conjugate as well as by the inability of spleen cells from tolerant animals to respond to a thymus-independent hapten-carrier conjugate. Even though the animals were fully tolerant, their spleen cells were activated by lipopolysaccharide (LPS) in vitro to produce normal numbers of plaque-forming cells against the hapten. The finding that spleen cells from tolerant animals could be activated by LPS into synthesis of antibodies against the tolerogen indicates that tolerance to thymus-dependent antigens does not affect B cells, but presumably only T cells. It is suggested that the only stringent test for the existence of B-cell tolerance is the inability of polyclonal B-cell activators to activate antibody synthesis against the tolerogen. The findings make it unlikely that B-cell tolerance to autologous thymus-dependent antigens exists and further indicate that such antigens cannot deliver activating or tolerogenic signals to B cells, although they are competent to combine with and block the Ig receptors.


Histocompatibility antigens controlled by the I region of the murine H-2 complex. I. Mapping of H-2A and H-2C loci.

Skin grafts were reciprocally exchanged in pairs of congenic lines identical in all genes except those located in the central portion of the H-2 complex. Seven such lines were tested: 6R, B10.AQR, A.TL, A.TH, 7R, 9R, and B10.HTT. In all donor-recipient combinations at least some grafts were rejected. In combinations differing at the IA subregion (and other central H-2 regions or subregions), all first-set grafts were rejected within 3 wk after transplantation, and all second-set grafts were rejected within 10 days. In combinations differing at the IC subregion (and other central regions, but not at the IA subregion) between 60 and 100% of first-set grafts were rejected, but some grafts survived for over 100 days. Most of the second-set grafts were rejected within 1 mo after grafting. This behavior of skin grafts indicated the presence of two histocompatibility loci in the I region, a strong one and a weak one. This conclusion was confirmed by genetic mapping which placed the strong locus in the IA subregion and the weak locus in the IC subregion. We designate the former locus H-2A and the latter H-2C. The same strain combinations used for the skin grafting were also used for determination of the capacity of I-region antigens to function as targets in the in vitro cell-mediated lymphocytotoxicity (CML) assay. Spleen cells from mice presensitized in vivo by skin grafting were restimulated in vitro and tested against 51Cr-labeled concanavalin A or lipopolysaccharide blasts. The testing revealed the presence in the I region of two loci coding for CML-target antigens. The two loci comapped with the H-2A and H-2C loci and were most likely identical to them. As in the skin grafting test, in the CML test, the H-2A antigens evoked stronger response than the H-2C antigens. Rejection of skin grafts across the H-2A and H-2C loci was accompanied by the production of Ia antibodies. Direct cytotoxic and absorption tests with Ia antibodies directed against antigens coded for by the IC subregion revealed the presence of IaC antigens on epidermal cells. We suggest that the products of Ia loci might function as transplantation antigens.


Transduction of bacteriocin determinants in group A streptococci.

Determinants of streptococcin A-FF22 (SA) production and host cell immunity have been transduced to three serologically distinct Group A streptococci. Streptomycin resistance markers were not cotransducible with bacteriocin determinants. SA+ transductants of strains unrelated to the parent SA+ strain were unstable but SA+ transductants of a spontaneous SA- derivative of the parent appeared to be stable.


A computer analysis of the Schreber Memoirs.

With the aid of a computerized system for content analysis, WORDS, the complete Schreber Memoirs was subjected to various multivariate reduction techniques in order to investigate the major content themes of this document. The findings included the prevalence of somatic concerns throughout the Memoirs, clear references to persecutory ideas and to Schreber's assumption of a redemptive role, complex encapsulated concerns about Schreber's relationship with God, a lack of any close relationship between sexuality and sexual transformation either to themes of castration or procreation, and the fact that neither sun, God, nor Flechsig was significantly associated with clusters concerning gender, sexuality, or castration. These findings are discussed in relation to psychodynamic interpretations furnished by prior investigators who employed different research methods.


Data on the absence of axon terminals of medial preoptic area neurons in the surface zone of the median eminence.

In order to investigate whether neurons of the medial preoptic area (MPOA) project to the surface zone (zona palisadica) of the median eminence (ME) and proximal part of the pituitary stalk, an electrolytic lesion or a frontal cut was placed in the pre- and suprachiasmatic region of the rat hypothalamus and the mentioned zone examined under the electron microscope. Degenerated nerve profiles were not observed int the zona palisadica following a lesion restricted to the MPOA or after a frontal cut at the posterior border of the MPOA. Altered elements were seen only in those cases in which the posterior part of the suprachiasmatic region was destroyed. The present data indicate that neurons of the MPOA do not terminate in the zona palisadica of the ME but presumably end on the nerve cells of the medial basal hypothalamus.


On the role of dopamine in the pathophysiology of anorexia nervosa.

Based on a review of the pathophysiology of the major symptoms of anorexia nervosa, it was suggested that increased activity of dopamine at central dopamine receptors plays a role in the pathophysiology of this disorder. Although dopamine receptor site hypersensitivity, or synthesis, of a false transmitter could account for this, a defect in negative feedback control mechanisms is more consistent with the known characteristics of anorexia nervosa. The possible role of pure dopamine antagonists in symptomatic treatment and of dopamine agonists in reversing this disorder was discussed.


[Human peripheral neurolymphomatosis (reticuloendothelial polyradiculoneuritis)].

This is the clinico-pathological report of a case of reticulo-endotheliosis of the nervous system in a 53-year-old white female. She had a history of transient facial palsy followed 6 months later by progressive weakness, paresthesiae and severe pain in both lower limbs. Clinical examination revealed signs of sensory and motor polyradiculoneuritis with involvement of the oculomotor, facial and trigeminal cranial nerves. She died 10 months after the onset because of bronchopneumonia. Pathological findings in the nervous system were limited to the cranial and spinal roots and ganglia. Histopathological examination showed intense infiltration by lymphocytes, histiocytes, plasmocytes and macrophages and a large amount of reticulin. The left oculomotor nerve, both Gasserian ganglia, the right trigeminal nerve and the lumbosacral nerves and ganglia were particularly involved. The previous literature on human peripheral neurolymphomatosis is reviewed and its differential diagnosis from Marek's disease, sarcomas, leukaemic polyradiculoneuritis, sarcoidosis and Hodgkin's disease of the nervous system is discussed. The importance of recognizing this variety of polyradiculoneuritis, and methods of treating it are emphasized.


Repair of denuded cranial bone by bone splitting and free-skin grafting.

As an alternative to the use of pedicled skin flaps for the repair of large defects of the scalp with denuded cranial bone, we recommend splitting of the bone and exposure of the diploë. The diploë is then covered with a free-skin graft, either immediately or after the formation of granulation tissue. The method is simple; it does not cause undue discomfort to the patient and does not detract from the chance of success if a more elaborate reconstructive procedure should be required later.


Minicomputer enhancement of scintillation camera images using fast Fourier transform techniques.

Minicomputer methods were developed to enhance lesions in scintillation camera images. This study was directed towards improving the diagnostic quality of liver images. A PDP-12 digital computer was interfaced to a Pho/Gamma HP III scintillation camera and programmed to carry out two-dimensional frequency-domain analysis and processing as an on-line operation. A two-dimensional frequency spectrum is produced. An interactive program allows the operator to construct graphically a frequency-domain filter and apply it to the data matrix. The filter is optimized using the image of a known phantom and then applied unchanged to the clincial liver image. An inverse Fourier transform produces an enhances image in the spatial domain. Significant enhancement of both phantom and liver images has been obtained.


Subtotal reconstruction of the hemimandible with an autogenous cancellous bone and marrow graft.

The use of an autogenous cancellous bone and marrow graft for subtotal reconstruction of the mandible is illustrated with a case report. The rationale of the treatment plan and the operative technique are discussed. Three years of postreconstruction follow-up examinations show good results with this technique.


Split-thickness skin grafts transplanted over exposed maxillary bone in dogs.

Studies in five dogs showed that skin grafts over decorticated bone became viable after two weeks; skin grafts over nondecorticated bone were necrotic and sloughed. After eight weeks, the grafts on the decoritcated areas were well vascularized; peripheral epithelial migration had almost completely closed the defects in the nondecorticated sites.


Alcian blue method for the museum display of squamous metaplasia in the larynx.

The Alcian blue method is described as an alternative to the use of pyronin for the immediate post-mortem demonstration of squamous in the larynx. Alcian blue-stained specimens can be stored for prolonged periods in 4 per cent formaldehyde in normal saline without loss of contrast and used as wet specimens for teaching purposes. Alcian blue-stained larynges showing squamous metaplasia can be permanently mounted for museum display in either Kaiserling's or Wentworth's fluids.


Immuno-histological observations upon the development of reticulum cell sarcoma in the mouse.

Detailed observations were made of the development of "reticulum cell sarcoma" in four strains of laboratory mice: SJL/J, NZB, PBA and (BALB/C X A)F1 hybrids injected with parental (BALB/C) spleen cells. Morphological evidence of a florid B cell immune response was present in all four strains, and was succeeded by a phase of atypical lymphoid hyperplasia, prior to the appearance of malignant neoplasms in lymph-nodes or spleen. These neoplasms correspond to descriptions of "reticulum cell sarcoma" of the mouse. The demonstration, by immunoperoxidase methods, of immunoglobulin within a proportion of these "malignant reticulum cells" reinforces the opinion, based on the morphological evidence of hyperplasia progressing to neoplasia, that the "reticulum cell sarcoma" of the mouse is B lymphocyte derived.


Serious group A streptococcal diseases in children.

The illnesses of 40 patients with diagnoses of septicemia, cellulitis with bacteremia, pneumonia empyema, and meningitis caused by Streptococcus pyogenes, Group A, are described. Twenty-five of 27 patients (93%) without underlying disease survived, whereas only seven of 13 children (54%) with underlying disease survived. Nine of the 25 patients who were otherwise normal and who survived these infections had prolonged, complicated illnesses. Four of these patients, and one who died, had septicemia without a focus of infection at the time of admission. Streptococcus pyogenes, Group A, although very sensitive to penicillin G and other antibiotics, can cause both severe and rapidly progressive disease in children.


The effect of visual feedback and self-scaling on plaque control behavior.

Psychological factors are involved in inducing patients to practice the plaque control necessary for periodontal health. It is suggested that oral hygiene behavior can be modified by increasing visual feedback by means of optical devices, and by giving patients the task of scaling their own teeth. The optical devices used for intraoral inspection must be specifically designed for this task. A pilot study was undertaken to test the modification in plaque control behavior in patients using a specially-designed optical system and performing self-scaling. Twelve patients participated in the study; six were given optical devices and taught self-scaling and plaque control, whereas the other six acted as controls, received a scaling from a hygienist, and were taught plaque control. All subjects received 3 hours of chairside time. Before treatment both groups had mean PHP indiced (plaque) of 3.2. Five months after the completion of treatment, the experimental group had a mean PHP index of 0.7, whereas the control group had a score of 1.9. The patients performing self-scaling demonstrated that they could remove supragingival calculus and extrinsic stains as effectively as a trained hygienist.


Osseous autografts. III. Comparison of osseous coagulum-bone blend implants with open curetage.

A clinical investigation was undertaken to compare regeneration of osseous defects following either osseous coagulum-bone blend grafts or open debridement procedures. Seventy-five sites in 28 patients were treated by the two procedures. The average fill in the 37 intraosseous defects treated by graft procedures (initial average depth = 4.22 mm, S.D. 1.73) was 2.98 mm, S.D. 1.44. The average fill in the 38 intraosseous lesions treated by open debridement procedure (initial average depth = 3.03 mm, S.D.0.80) was 0.66 mm, S.D. 0.80. Statistical analysis showed a significant difference (P greater than 0.01) in fill patterns between the bone blend and open debridement responses in favor of graft treated sites. Therefore greater levels of osseous regeneration apparently took place in our cases following osseous coagulum-bone blend autogenous graft procedures than following open debridement procedures in all types of defects studies.


Evaluation of Mannich bases and related compounds as inhibitors of mitochondrial function in yeast and inhibition of blood platelet aggregation, blood clotting, and in vitro metabolism of 5-dimethylamino-1-phenyl-1-penten-3-one hydrochloride.

Dimethylamino-1-phenyl-1-penten-3-one hydrochloride (Ia) and 32 analogs were tested for inhibition of respiratory-dependent growth in Saccharomyces cerevisiae. Thirteen of the 33 compounds tested appeared to affect mitochondrial function, since the inhibition of respiratory-dependent growth was statistically greater than the inhibition of growth on fermentable energy sources. Inhibition of mitochondrial function in yeast and growth inhibition of an in vitro culture of human epidermoid carcinoma (KB) were positively correlated since 83% of the compounds tested either had mitochondrial-inhibiting properties and significant activity in the KB test or were inactive in both tests. Similarly, 78% of compounds tested showed murine toxicity and mitochondrial inhibition or had no effect on murine toxicity and yeast mitochondrial function. Injection of Ia into rats resulted in the appearance of blood in the urine and feces. Compound Ia inhibited adenosine diphosphate and collagen-induced aggregation of rat platelets but had no effect on blood clotting. TLC, following incubation of Ia with a rat liver extract, showed that the structure of Ia was not enzymatically modified and indicated activity per se on platelet aggregation and mitochondrial function.


Evaluation of 2-benzylidenecyclohexanones and 2,6-bis(benzylidene)cyclohexanones for antitumor and cytotoxic activity and as inhibitors of mitochondrial function in yeast: metabolism studies of (E)-2-benzylidenecyclohexanone.

Some 2-benzylidenecyclohexanones, 2,6-bis(benzylidene)cyclohexanones, and related compounds were evaluated for antitumor and cytotoxic activities; (E)-2-benzylidenecyclohexanone (Ia) was shown to have significant cytotoxic properties and a potent inhibitory effect on yeast mitochondria. After intraperitoneal injection of Ia, unchanged drug and a metabolite, tentatively identified as 2-(p-hydroxybenzyl)cyclohexanol, were found in the urine. No metabolites were found in the feces. Oral administration of Ia afforded three unidentified metabolites in the urine and three unidentified metabolites in the feces.


Antimalarials V: aminobenzothiazoles.

Four mono- and dialkylated 4-aminobenzothiazoles (VII-X) were prepared as analogs of potent causal prophylactic drugs in the 8-aminoquinoline series. Compounds VII and VIII were toxic at 80 mg/kg in the chick; IX was inactive at 640 mg/kg. In a sporozoite-induced mouse test system, X was inactive at 30 mg/kg and toxic at 480 mg/kg. None of the compounds was active as a suppressive drug.


The cortical visual areas of the sheep.

1. A stereotaxic method for the sheep brain is described. 2. At its widest part the primary visual area (Visual I) of each hemisphere extends approximately 20 mm anteroposteriorly and, when unfolded, approximately 35 mm from side to side. It occupies both walls of the lateral sulcus, and extends medially to the medial wall of the hemisphere and to the depth of the ectolateral sulcus laterally. 3. The most lateral part of the primary visual area includes 10-15 degrees of the ipsilateral field; the contralateral field is represented to 135 degrees from the mid line. 4. Visual II also includes a strip of ipsilateral representation on its medial edge and extends to the supra-sylvian sulcus on the lateral surface of the brain. The furthest lateral representation recorded was 130 degrees lateral. 5. Most of both visual areas is concerned with the area centralis and the visual streak. The remainder of the retina has very little cortical representation. 6. Most cells in Visual I are simple with orientational and sometimes directional sensitivity. Some complex and hypercomplex cells have been seen in Visual I, and these predominate in Visual II. Receptive field sizes from 0-25 to 10 degree were found. Within 15 degrees of the vertical meridian, binocular cells are common in both Visual I and II.


Prolonged inactivation of cortical pyramidal tract neurones in cats by distension of the carotid sinus.

1. We have investigated the effects of stimulating carotid sinus baroreceptors upon the activity of single cortical pyramidal tract cells (PT-cells) in anaesthetized cats.2. Extracellular potentials were recorded from PT-cells, which were driven orthodromically (1/sec) by stimulating thalamic nuclei (N. ventralis lateralis, N. ventralis posterolateralis) or afferent nerves in the contra-lateral forepaw. Baroreceptors were stimulated by inflating small balloons placed in the bifurcations of one or both common carotid arteries.3. Distension of the carotid sinus caused a prolonged depression of the orthodromically evoked discharge of eighteen of thirty-two PT-cells, the effect ranging from a 15% reduction in firing to complete cessation of activity (average reduction, 39%). The depression of firing outlasted the period of balloon inflation by an average of 85 sec; in some experiments inhibition persisted for as long as 2-3 min.4. Inflation of the balloon caused a reflex fall in arterial pressure (mean decrease, 29 mmHg), pressure reverting to the control level as soon as the balloon was deflated. Single fibre recording from the carotid sinus nerve confirmed that stimulation was confined to baroreceptors and that carotid chemoreceptors were unaffected by balloon distension.5. Depression of PT-cell activity could not be explained simply by a fall in cerebral blood flow resulting from the reflex fall in arterial blood pressure. When a comparable or greater degree of hypotension was produced by bleeding or peripheral vagal stimulation, PT-cell firing fell in a third of experiments but reverted immediately to the control level when arterial pressure was restored. Thus some factor other than a decrease in cerebral perfusion pressure was responsible for the prolonged inhibition evoked by carotid sinus distension.6. Our results are consistent with the hypothesis that baroreceptor input to the reticular formation exerts an ascending influence on cortical mechanisms, with prolonged inhibitory effects comparable to those previously demonstrated at spinal level.


Measurement of personality traits and their relation to patient satisfaction with complete dentures.

1. There was a high incidence of the personality traits of hypochondriasis, depression, hysteria, and manifest anxiety in the 70 complete denture patients of this study. 2. Most patients in this study were satisfied with the complete dentures received. 3. There was no significant relationship between the personality traits of hypochondriasis, depression, hysteria, and manifest anxiety and the degree of patient satisfaction with dentures. 4. There was no significant relationship between the personality traits of hypochondriasis, depression, hysteria, and manifest anxiety and the techinical quality of dentures. 5. There was no significant relationship between the technical quality of complete dentures and the degree of patient satisfaction with the same dentures.


Bone-titanium implant response to mechanical stress.

The purpose of this study was to investigate the nature and strength of any bond which may develop between alveolar bone and titanium allow implants. Implants were placed in a previously prepared edentulous region in the mandibles of dogs. The implants were conical in shape with circumferential grooves to provide axial retention. Five months later the implants were rotated. No indication was found of an adhesive bond being broken.


Edentulous gnathologic recordings utilizing "vacustatics".

Securing clutches to edentulous ridges by vacustatics for a pantographic recording is useful for effecting a desirable result. This technique is a possible answer for those edentulous patients with occlusal problems who have never known comfort while wearing dentures. A procedure has been described utilizing a modification of the vacustatic technique to obtain accurate pantographic recordings on edentulous patients. These recordings enable the dentist to develop a gnathologic-oriented occlusion for the problem denture patient in an attempt to eliminate destructive loading forces on the residual ridges.


Strain-dependent thermosensitivity influencing intracellular differentiation of Trypanosoma cruzi in cell culture.

Temperature strongly influenced morphogenesis of intracellular trypomastigotes in cell culture infected with 2 different strains of T. cruzi. With the Gilmar strain the amastigote-to-trypomastigote differentiation readily occurred at 33 and 37 C, whereas the CL strain differentiation took place at 33C but was inhibited at 37 C. The possiblity of this selective thermosensitivity resulting from mutational adaptation of the parasite is discussed.


Comparative kinetics of arginine and lysine transport by epimastigotes and trypomastigotes from two strains of Trypanosoma cruzi.

Three-day-old cultures of Y and MR strains of Trypanosoma cruzi ahd a higher rate of lysine and arginine uptake than 10-day cultures. Amino acid uptake by cells of the MR strain was consistently higher than that of the Y strain. Flagellates separated on DEAE-cellulose columns have normal structure, motility, and infectivity; they have the higher rates of lysine and arginine uptake than the original 3- and 10-day cultures. In addition passage through DEAE-cellulose columns modified the kinetic behavior of amino acid transport systems in the flagellate membranes.


Studies on the release of gonadotrophins during the superfusion of isolated rat pituitaries in a continuous flow system.

A continuous flow system has been developed to study the endocrine functions of isolated organs. The procedure has been used to investigate the effect of a synthetic gonadotrophin-releasing hormone (Gn-RH) upon the anterior pituitary gland of the adult male rat. A Radiometer blood gas/pH analyser was used to monitor the pH and partial pressures of oxygen and carbon dioxide in the perfusion medium. A series of six experiments with four pituitaries per flask established that the rate of gonadotrophin release under basal conditions was 646 +/- 301 (S.D.) ng LH/ml and 404 +/- 124 (S.D.) ng FSH/ml. The duration and intensity of the response to Gn-RH was assessed by measuring the areas under the curves according to the trapezoidal rule. A significant increase in the release of FSH and LH was obtained by the administration of 250 ng Gn-RH/ml medium, and dose-response curves were produced for up to 10 mug/ml.


Pregnancy-specific antigens in the sheep: application to the diagnosis of pregnancy.

Antisera to 14-day-old sheep embryos were raised in rabbits and used to detect antigens specific to pregnancy by immunofluorescent staining and haemagglutination. Non-specific antibodies were removed by repeated absorptions of the antisera with homogenates of liver and kidney from non-pregnant ewes. The pregnancy-specific antigens were detected using immunofluorescence in the embryo, myometrium, maternal blood and CL as early as Day 8. No fluorescence was detected in pituitary, hypothalamus, liver, kidney, skeletal muscle or endometrium of pregnant ewes, or in any tissues of non-pregnant ewes. Haemagglutination occurred when a 1:8 dilution of rabbit anti-sheep embryo sera was added to blood obtained from ewes between Days 6 and 50 of pregnancy, but not when added to blood from non-pregnant ewes, rams and wethers or from pregnant mares, sows and cows. The immunological activity was removed from the anti-sheep embryo sera by absorption with homogenates of 14-day-old sheep embryo or pregnant uterus, or erythrocytes from Day 14 pregnant ewes, confirming that the antigens were specific to pregnancy. The presence of these antigens provides a basis for a haemagglutination test for pregnancy from Day 6 after mating and may be involved in the maternal recognition of pregnancy in the ewe.


Regulation of gonadotrophin secretion in rams from birth to sexual maturity. II. Response of the pituitary-testicular axis to LH-RH infusion.

The response of the pituitary-testicular axis to LH-RH infusion was investigated in rams from birth to sexual maturity. During early postnatal life ram lambs were responsive to LH-RH stimulation and heightened pituitary sensitivity was observed in rams aged 2-3 months. It is suggested that a change in sensitivity of the pituitary-testicular axis occurs at this time and perhaps represents the time of initiation of the pubertal process.


Pregnancy blocking in the vole, Microtus agrestis. I. Effect of the social environment.

Pregnancy failed in a high proportion of newly mated Microtus agrestis females when they were exposed to a strange male between 48 and 72 hr after mating with a stud male. This effect of the strange male was testosterone dependent. Direct contact with the strange male was normally necessary, and even a single barrier of wire mesh between the female and strange male prevented the male from exerting his pregnancy-blocking effect. The results suggest that the stimuli mediating pregnancy blocking in the vole may differ from those operative in the mouse.


Pregnancy blocking in the vole, Microtus agrestis. II. Ovarian, uterine and vaginal changes.

Pregnancy blocking in M. agrestis was associated with a rapid degeneration of CL, growth of follicles, a loss of embryos and return of the uterus to its non-pregnant state, and a return to cornified vaginal smears. These results are discussed in relation to the proposal that the immediate cause of pregnancy block is a failure of prolactin secretion resulting in a failure of CL function.


Changes in total nitrogen, lipoproteins and amino acids in epididymal and ejaculated spermatozoa of bulls treated orally with ethylene dibromide.

Protein changes in epididymal and ejaculated spermatozoa were studied in bulls treated orally on alternate days with a total of 10 doses (each of 4 mg/kg body weight) of ethylene dibromide. No significant changes were found in the total nitrogen, amino acid or lipoprotein contents of the spermatozoa collected either from the epididymis 1 day after the last dose, or from ejaculates 9-13 days after the end of the treatment. Significant changes were found in the percentage composition of amino acids of the sperm proteins and lipoproteins but the changes differed in the caput, cauda and ejaculated spermatozoa.


Double-blind study of Naproxen in osteoarthritis of the knee joint.

To determine the effectiveness of naproxen in the treatment of osteoarthritis of the knee joint, a double-blind cross-over study against placebo was carried out on 61 patients. Statistically significant positive therapeutic effects were observed, including analgesia, increased mobility, decrease in joint swelling and improvement in activities of daily living. Side effects were infrequent, mild and disappeared rapidly.


Urinary fibrin split products in lupus nephritis.

Antigen-antibody interaction and fibrin deposition at the glomerular basement membrane can release activators that ultimately convert fibrin into degradation products of varying molecular size. Thus, increased urinary fibrinogen/fibrin split products (FSP) might be expected in active lupus nephritis. A longitudinal study was done on 27 patients with biopsy-proven lupus nephritis. Those patients who were persistent FSP excretors were found to be at a significantly greater risk of progressive nephritis and renal death than those who were FSP negative. It is suggested that FSP excretion in lupus nephritis, particularly on a continued basis and despite normalization of other renal disease parameters, is a grave prognostic sign.


Antimalarial activity of some novel derivatives of 2,4-diamino-5(p-chlorophenyl)-6-ethylpyrimidine (pyrimethamine).

Thirteen new analogs of 2,4-diamino-5(p-chlorophenyl)-6-ethylpyrimidine (Daraprim, pyrimethamine) in which the alph position of the 6-ethyl substituent was modified were prepared. The respective oxygens analogs (ketals, ketone, alcohol), the dimethyl hydrazone, and the nitrone displayed activities in the range of 1/4 to 1/16 that of pyrimethamine toward Plasmodium berghei in mice. The therapeutic ratios of some of these compounds may be slightly better than that of pyrimethamine.


The inherent paradox of clinical trials in psychiatry.

The authors sum up the central issue of ethics in the conduct of controlled clinical trials in these two paradoxes: 'first, it is unethical to use treatment the efficacy of which has not been examined scientifically; second, it is also unethical to examine the efficacy of treatment scientifically.' In this paper they set out to demonstrate how these antithetical statements apply in controlled trials conducted in psychiatric patients. In such trials the problem of obtaining informed consent may be acute, but in these patients giving 'informed' consent might contribute to a further exacerbation of the illness. Nevertheless the problem cannot be evaded, and scientific judgments must be applied to treatment for it to be sound and improved for the further benefit of patients. These problems in the case of psychiatric controlled trials are a part of the methodology, and in Germany a new drug law has been drafted to attempt to clarify the issue. The authors briefly discuss its application, and its consequences if such a law were enacted. British psychiatrists have exactly the same problems to face but so far no attempts have been made to establish a legal framework.


The ethics of clinical trials.

In summary, the discussion by Professors Helmchen and Müller-Oerlinghausen of the morality of clinical trials has emphasized a point that is frequently overlooked. It is an essential to consider those situations in which it might be unethical not to conduct a trial as it is to be concerned about the ways in which trials might restrict the rights of the individuals taking part in them. They and I have dealt mainly with the first of these two issues because it has been relatively neglected. The second is, of course, equally important and has rightly received much attention. Both matters deserve further public discussion.


Polymorphic acetylation of nitrazepam.

Nitrazepam is metabolized in part by nitro-reduction to an amine followed by acetylation. This acetylation step has been shown to be under the control of the same genetic polymorphism as sulphamethazine (syn: sulphadimidine).


Congenital malformations of the central nervous system in spontaneous abortions.

A study of 2620 pregnancies ending in spontaneous abortion revealed a CNS defect in 3.6% of embryos and fetuses, and 3% of all complete conceptuses. The type of malformation observed varied with the gestational age at expulsion, encephaloceles being predominant in earlier specimens, while more typical anencephalus and spina bifida were more common among later abortions. Chromosome abnormalities were found in 40% of abortuses with CNS defects, but were almost entirely confined to those which were still at the embryonic stage of development. 53% of the latter were chromosomally abnormal, which is the same as the proportion found among embryos without a CNS malformation. Using published life-tables of recognized pregnancies it was estimated that the prevalence of anencephalus, spina bifida, or related malformation (other than hydrocephalus), without a chromosome anomaly, is 5.3 per thousand conceptuses at the beginning of the eighth week of gestation. By comparing this with the prevalence in total births, it was further estimated that only 24% of these are born alive, with 54% aborting spontaneously and 22% being stillborn.


Stereo photomicrography of Golgi preparations.

Photomicrographs of thick sections taken with reciprocal, lateral illumination in a compound microscope produce stereo-pairs. The method is particularly useful with thick celloidin sections of nervous tissue impregnated with the Golgi selective silver technique.


A method of embedding tissue culture preparations in situ for transmission electron microscopy.

A method for embedding tissue culture preparations, grown on Millipore filters, in Araldite is described. Accurate light microscopic localization of areas suitable for ultrathin sectioning is possible. The plane of sectioning relative to the Millipore filter can be varied to suit individual experimental needs.


Environmental health aspects of fungicides. I. Dithiocarbamtes.

A variety of dithiocarbamate fungicides, as well as their principal trace impurities, and metabolic or chemical degradation products are reviewed. Major focus is on  their chemical and toxicological features (primarily carcinogenic, teratogenic, and mutagenic), use patterns, and residues. The compounds discussed include (1) ethylene bis(dithiocarbamated) (maneb, zineb, nabam), (2) dithiocarbamates (febram, ziram), and ("3) thiuram disulfate (thiram) and ethylene thiourea.


The centrineurogenic etiology of the respiratory distress syndrome: protection by unilateral chronic pulmonary denervation in hemorrhagic shock.

Anemic beagles were subjected to 40 mm Hg hemorrhagic shock for 2 hours, which uniformly induced the pulmonary lesions of the "respiratory distress syndrome" (RDS) bilaterally in all six controls. For six subjects with complete denervation of the left lung 2 months previously, the shock regimen induced the lesions in the normally innervated right lungs; all reimplanted, denervated left lungs remained anatomically intact. This is presented as additional evidence for a centrineurogenic etiology for RDS.


Penetrating trauma of colon, cava, and cord.

A case is presented of a young police officer shot in the abdomen, sustaining injuries to colon, cava, and cord. Each injury was surgically managed in what was felt to be an appropriate manner, with early antibiotic therapy. As complications developed, aggressive measures were taken to correct them, with some success as far as pulmonary and renal failure were concerned, but with complete inability to reverse the meningitis and cerebritis caused by E. coli, and leading to a fatal outcome.


Relation between Salmonella typhimurium biotypes and drug resistance, Teheran, Iran (1962-1973).

According to the procedure of Cordano (1971), the identification of biotypes of 118 strains of Salmonella typhimurium isolated from stools or rectal swabs of patients with sporadic cases of diarrhoea on the Central Plateau during the period 1962-1973 revealed that: From 118 S. typhimurium, 65 (55-1%) were biotype "d", 50 (42-4%) were "a" and three (2-5%) were "b". The predominant biotype was "d", followed by the "a" biotype, and "b" was rarely encountered. Biotype "d" has existed since 1965, and after that date has increased. Biotype "a" existed from the beginning of the study, but has decreased during the period 1962-1973. Sensitivity tests were performed according to Bauer (1966). Biotypes "d" and "a" showed a high degree of resistance to tetracycline, chloramphenicol, streptomycin, triple-sulfa, ampicillin, furazolidone, kanamycin, neomycin, paromomycin, cephalothin and co-trimoxazole. All isolated biotypes "d" were multiple drug-resistant, while some of the strains of biotype "a" were resistant and some sensitive. All three biotypes "b" were sensitive to all drugs examined. Resistance to drugs for biotypes "d" and "a" increased with time. The predominant pattern of resistance for all biotypes was found to be resistance to eight drugs: tetracycline, chloramphenicol, streptomycin, triple-sulfa, ampicillin, kanamycin, neomycin and paromomycin (Tc, Cm, Sm, Su, Am, K, N, Par). Considering the relationship between resistance pattern and biotypes, the predominant pattern in biotype "d" was resistance to eight drugs (Tc, Cm, Sm, Su, Am, K, N, Par) (47-7%), and in biotype "a" was resistance to nine drugs, tetracycline, chloramphenicol, streptomycin, triple-sulfa, ampicillin, furazolidone, kanamycin, neomycin, paromomycin (Tc, Cm, Sm, Su, Am, Fx, K, N, Par) (28%).


Chloroquine-resistant falciparum malaria from Irian Jaya (Indonesian New Guinea).

A strain of Plasmodium falciparum, transmitted in Irian Jaya (Indonesian New Guinea) was isolated in 1974 and sent to the University of Maryland for characterization in nonimmune volunteers. At Maryland the Indonesia (Whit.) strain, as it has been designated, was transmitted to colonized Anopheles stephensi. Prophylactically, it was not suppressed by proguanil hydrochloride 100 mg. daily. Curatively, parasitaemia was not cleared by treatment with 1-5 g. (base) in three days of chloroquine or amodiaquine (RII responses), nor by treatment with 150 mg. of pyrimethamine in three days (RIII), and some resistance was also shown to quinine. A single dose of 1-5 g. of mefloquine (WR 142,490) produced radical cure in the two patients treated with this new 4-quinolinemethanol compound.


Serial histomorphometric and histochemical bone biopsy studies in dialysis and transplantation.

A serial bone biopsy longitudinal study has been undertaken to asses the effects of Dialysis and Transplantation on uremic osteodystrophy. The clinical material consists of: normal (24 cases, 61 biopsies), patients with moderate renal failure on free diet (50 c., 61 b.), patients on Low Protein Diet (146 c., 251 b.), patients on Regular Dialysis Treatment (114 c., 256 b.), patients submitted to Transplantation (50 c., 84 b.). A significant correlation has been documented between duration of low protein diet and bone changes. In long-term dialysis patients remarkable differences have been found in "late" dialysis starting time (mean value of creatinine clearance at the beginning of treatment 2.04 +/- 1.7) in respect to "early" starting-time (mean value 13.1 +/- 3.9). In late group bone histomorphometry showed quite evident signs of secondary hyperparathyroidism  and hyperosteoidism which remarkably worsened 3-4 years after dialysis. The aminoacids composition of the bone showed an increase in the total amount of aminoacids during dialysis, expecially for proline, hydroxyproline and glycine. In early group both basic values and progression rate of bone lesions were less severe. In transplanted patients with good renal function (serum creatinine less than 1.4 mg%) bone histomorphometric analysis showed a rather rapid disappearance of uremic bone lesions. A significant correlation was found between serum PTH, renal function and bone histology. On some occasions signs of secondary hyperparathyroidism were documented even after 16 months. A good correlation between inactive bone surfaces and immunosuppressive regimen was found.


Bacteriophage phiX174 single-stranded viral DNA synthesis in temperature-sensitive dnaB and dna C mutants of Escherichia coli.

We asked if phiX174 single-stranded DNA synthesis could reinitiate at the nonpermissive temperature in dnaB and dnaC temperature-sensitive host mutants. The rates of single-stranded DNA synthesis were measured after the removal of chlorampheicol that had been added at various times after infection to specifically stop this stage of phiX174 DNA synthesis. Reinitiation was not defective in either mutant host. Our data suggested that the reinitiation of the single-stranded stage of phiX174 DNA synthesis in these experiments was analogous to the normal initiation of this stage of phiX174 DNA synthesis in infections without chloramphenicol. Assuming this to be the case, we conclude that the host cell dnaB and dnaC proteins are not essential for the normal initiation of the single-stranded synthesis stage of phiX174 DNA synthesis. In related experiments we observed that in  the dnaC mutant host at the permissive temperature, phiX174 replicative form DNA synthesis continued at its initial rate even during the single-stranded DNA synthesis stage. This indicates that these two stages of phiX174 DNA synthesis are not necessarily mutually exclusive.


Lysogenization of Escherichia coli by bacteriophage Lambda: complementary activity of the host's DNA polymerase I and ligase and bacteriophage replication proteins Q and P.

When bacteriophage lambda DNA replication is blocked by mutation in phage genes O or P, the efficiency of lysogenization drops to a very low value unless high multiplicities of infecting phage are used. Our results show that even at high multiplicity, lambda O or P mutants cannot efficiently lysogenize some hosts that are defective in either DNA polymerase I or DNA ligase. Covalent closure of infecting DNA molecules, a preliminary step for insertion according to Campbell's model and an obvious candidate for this lysogenization defect, appears to occur normally under our conditions. In addition, prophage excision as measured by the frequency of curing O- and P- lysogens seemed normal when tested in the poll- strain. These results suggest that the Escherichia coli enzymes DNA polymerase I and ligase, and phage proteins O and P, are able to provide some complementary activity whose function is required specifically for prophage integration.


Identification of the gene controlling the synthesis of the major bacteriophage T5 membrane protein.

After infection of Escherichia coli B by bacteriophage T5, a major new protein species, as indicated by polyacrylamide gel electrophoresis, appears in the cells' membranes. Phage mutants with amber mutations in the first-step-transfer portion of their DNA have been tested for their ability to induce membrane protein synthesis after they infect E. coli B. We have found that phage with mutations in the Al gene of T5 do not induce the synthesis of the T5-specific major membrane protein, whereas phage that are mutant in the A2 gene do induce its synthesis. We conclude that gene Al must function normally for T5-specific membrane protein biosynthesis to occur and that only the first 8% (first-step-transfer piece) of the DNA need be present in the cell for synthesis to occur.


Function of gene 49 of bacteriophage T4. II. Analysis of intracellular development and the structure of very fast-sedimenting DNA.

With the exception of mutants in gene 49, all mutants in phage T4 defective in the process of head filling accumulate a normal replicative DNA intermediate of 200S. Mutants in gene 49 produce a very fast-sedimenting (VFS) DNA with s values of greater than 1,000S. The intracellular development of the VFS-DNA generated in gene 49-defective phage-infected cells was followed by sedimentation analysis of crude lysates on neutral sucrose gradients. It was observed that the production of a 200S replicative intermediate is one step in the development of VFS-DNA. After restoring permissive conditions the development of the VFS-DNA can be reversed, but the 200S form is not regenerated under these conditions. The process of head filling can take place from the VFS-DNA under permissive conditions. From the absence of other components in the VFS-DNA complexes, its high resistance to shearing, its resistance against the attack of the single-strand-specific nuclease S1, and from its appearance in the electron microscope, a complex structure of tightly packed DNA is inferred. The demonstration by the electron microscope of branched DNA structures sometimes closely related to partially filled heads is taken in support of the idea that the process of head filling in gene 49-defective phage-infected cells is blocked by some steric hindrance in the DNA. In light of these results, the role of gene 49 is discussed as a control function for the clearance of these structures. A fixation procedure for cross-linking of gene 49-defective heads to the VFS-DNA allowed us to study progressive stages in the process of head filling. Electron microscopic evidence is presented which suggests that during the initial events the DNA accumulates in the vertexes of the head.


Strain selection during serial passage of Trichoplusia in nuclear polyhedrosis virus.

Two strains of a nuclear polyhedrosis virus (NPV) of Trichoplusia ni were isolated on the basis of plaque morphology. They are designated as MP (having greater than 30 polyhedra per nucleus) and FP (having fewer than 10 polyhedra per nucleus). Serial, undiluted passage of plaque, purified MP nonoccluded. Virus (NOV) in tissue culture led to the production of the FP phenotype detectable at passage 9. With continued serial, undiluted passage, FP became the predominant strain. Comparative growth curves showed that FP NOV are released faster than MP NOV. MP morphology was not observed after 14 serial, undiluted passages of plaque-purified FP. By the plaque neutralization assay, NOV from both strains of virus was neutralized by the homologus and heterologous antisera. The FP phenotype was observed when FP virus was grown in culture at 17, 22, and 27 C. Hence, the FP phenotype was not considered to be the result of temperature-inhibited crystallization of polyhedrin under standard tissue culture conditions. The NOV of both strains killed insects when injected directly into the hemocoele of T. ni larvae. Only MP inclusion bodies were virulent per os. The FP inclusion bodies fed to cabbage looper larvae did not kill, and no infectious agent could be detected in the hemolymph. Electron micrographs of MP polyhedra showed bundles of nucleocapsids of normal length within the polyhedra, whereas FP polyhedra contained heterogeneous, electron-dense material, which could account for their lack of pathogenicity.


Translation of T7 RNA in vitro without cleavage by RNase III.

T7 early mRNA's are generated from a high-molecular-weight precursor RNA by site-specific RNase III cleavage. When T7 DNA is transcribed in vitro by Escherichia coli RNA polymerase, the transcript is a large, single-piece RNA equivalent to the in vivo precursor RNA. The T7 RNA synthesized in vitro can be translated as a polycistronic messenger without cleavage by RNase III. All T7 early proteins are synthesized in an RNase III-free, protein-synthesizing system directed by the uncleaved T7 RNA.


Novel replicative properties of a capsid mutant of bacteriophage phi chi 174.

A capsid mutant of bacteriophage phi chi 174 demonstrates altered requirements for the conversion of viral single-stranded DNA to double-stranded replicative form DNA. In the presence of puromycin at 42 C, wild-type phi chi 174 is unable to complete this replicative event, whereas phi chi ahb is able to do so. Furthermore, in contrast to wild-type phi chi 174, formation of phi chi ahb parental replicative form DNA is sensitive to rifampin under certain experimental conditions. These data suggest that the mutant capsid proteins of phi chi ahb influence the biosynthesis of phi chi ahb complementary strand DNA.


Function of gene 49 of bacteriophage T4. I. Isolation and biochemical characterization of very fast-sedimenting DNA.

Very fast-sedimenting DNA was isolated from cells after infection with gene 49 defective phage T4. This DNA appeared membrane bound throughout the time after infection and could be isolated either in the membrane-bound form (M-DNA) or free of membrane (released DNA) depending on the lysis procedure. Released DNA formed complexes of marked stability with sedimentation velocities between 1,400S and 2,100S. These complexes did not seem to contain material other than DNA. This was concluded from the results of RNA, protein, and membrane labeling experiments and density analysis. In addition, these complexes were resistant against treatment with n-butanol, phenol. chloroform-methanol, sodium dodecyl sulfate, Sarkosyl, Pronase, RNase, or lysozyme. The observation that more then 90% of the purified very fast-sedimenting DNA is retrapped by magnesium-Sarkosyl crystals (M-band) suggests that the M-band technique may not be sufficient as a test for DNA-membrane attachment.


Neurology of micturition.

The understanding, diagnosis and management of neurologic dysfunction of the bladder have undergone considerable changes during the last 2 decades. These changes were the result of animal experimentation into physiology and pharmacology and the accelerated use of biomedical engineering technology. The implementation of these advances will require physician re-education in the neurology of micturition.


The effects of long-term alternate-day steroids on parameters of adrenal function in renal transplant patients.

Urinary androgen fractions, with other parameters of adrenal function, were assessed in renal transplant patients on long-term alternate-day steroid therapy. Urinary 17-ketosteroids and plasma cortisol values were low normal or slightly reduced in female patients and normal in male patients. In female patients the following urinary androgen fractions were depressed to less than the normal range: androsterone, dehydroepiandrosterone, etiocholanolone and 11-ketoetiocholanolone; 11-hydroxyetiocholanolone was not detectable. In male patients dehydroepiandrosterone and 11-ketoetiocholanolone were depressed to less than the normal range. Adrenal scan using 131I-19-cholesterol failed to image the adrenal glands in 5 of 7 patients studied, confirming the lack of an adrenocorticotropic hormone effect, with corresponding depression of the hypothalamic-pituitary-adrenal axis. These studies demonstrate the value of fractionating urinary 17-ketosteroids in assessing adrenal reserve and are a more sensitive index of adrenal suppression than the total 17-ketosteroids alone.


Renal transplantation in patients with urologic abnormalities.

Of patients undergoing renal transplantation during a recent 18-month period 42 per cent had significant urologic abnormalities. A thorough pre-transplant evaluation is especially critical in these patients. Massive reflux is an indication for pre-transplantation nephroureterectomy. Reconstructive operations provided a functional bladder in some patients who had previously undergone urinary diversion. Other patients required formation of intestinal conduits. Suggestions for the management of transurethral prostatectomy in patients with renal failure are outlined. Patients with a variety of abnormalities of the urinary tract had a transplantation success rate comparable to that of azotemic patients with normal urinary systems.


Foreign body migration from the bladder.

Because of the unusual route 2 cases of foreign body migration from the bladder are reported. In 1 case a thermometer was inserted into the bladder and penetrated into the peritoneal cavity. In the other case a thermometer penetrated from the bladder into the prevesical space. These penetrations occurred without any obvious manifestations after the thermometers were inserted into the bladder.


Tumor eradication by radiofrequency therapy. Responses in 21 patients.

Tumor blood flow, measured by an isotope dilution technique, is only 2% to 15% of that of the surrounding tissue. This sluggish circulation differentiates cancer from normal tissue and forms the basis for a new therapy that entails the transfer of radiofrequency (RF) energy for heating tissues locally. The heated tissue is cooled by the circulation of blood, which carries away the heat. Impaired perfusion, as in cancers, impedes cooling. Heating by RF elevated the temperatures of animal and human cancers by 5 to 9.5 C above that of healthy tissue. The heat eradicated the animal cancers without destruction of normal tissue. Radiofrequency therapy produced tissue necrosis or substantial regression of cancer in 21 patients.


[Revaluation of gentamicin in laboratory and clinical studies (author's transl)].

The MIC of gentamicin and other antibiotics against clinical isolates was determined, and the following sensitivity distribution was obtained. a) Against 54 strains of Staphylococcus aureus, GM had the lowest MIC, followed by TOB, DKB, BB-K8 in order. The distribution range of 0.1-6.25 mug/ml was noted with GM. The peak of MIC was 1.56 mug/ml. b) Against 54 strains of E. coli, the lowest MIC was obtained with GM, and 53 strains (98%) were in the range of 0.4-6.25 mug/ml. The peak of MIC was 3.12 mug/ml. GM was followed by TOB, CL, DKB in order of superiority. c) Against 27 strains of Klebsiella pneumoniae, GM and TOB had the lowest MIC, showing the peak of MIC of 0.8 mug/ml. No significance difference was noted between GM and TOB. GM and TOB were followed by DKB, CL, BB-K8 in order of superiority. d) Against 27 strains of Proteus, GM had the lowest MIC, followed by TOB, DKB and BB-K8 in order. But the peak was 6.25 mug/ml even in GM. The activity of antibiotics against Klebsiella pneumoniae was generally low. e) Against 54 strains of Pseudomonas, the peak of MIC of GM was 3.12 mug/ml and 49 strains (91%) were in the range of 1.56-12.5 mug/ml. Whereas TOB had the peak value of 0.8 mug/ml and 49 strains (91%) were in the range of 0.4-3.12 mug/ml. TOB was followed by DKB, GM, BB-K8 in order of superiority.


Clinical experience with gentamicin in complicated urinary tract infections (author's transl).

Gentamicin 40 mg was intramuscularly admininistered two times daily to 15 patients with complicated urinary tract infections. The results are as follows 1. The clinical efficacy of gentamicin was excellent in 12 cases (80.0%), good in 2 cases (13.3%) and null in 1 case (6.7%). The effective rate was 93.3%. 2. Bacteria disappeared in 16 strains (84.2%), colonized in 3 strains (15.8%) out of 19 isolates. 3. BUN, GOT and GPT values were determined before and after GM administration, and no significant abnormal finding attributable to GM was observed in this clinical study.