Unusual Enterobacteriaceae: lactose-positive Salmonella typhimurium which is endemic in São Paulo, Brazil. Since 1971 a lactose-positive (lac+) Salmonella typhimurium variety Copenhagen has been endemic in the city of Sao Paulo. The strain is a strong lactose fermenter and resembles Escherichia coli on primary plating media and in triple sugar iron agar. Although most isolates of the strain have uniform properties, some have slightly different antigens, antibiograms, phage types, or fermentation patterns. Most isolates have come from stools of infants under 1 year of age and are probably hospital acquired; however, other isolates are probably community acquired. Eighteen other lac+ Salmonella isolated in the United States were also studied. Most of these strains resembled E. coli on primary plates and triple sugar iron agar; thus their identification would pose a problem for most clinical laboratories. A simple procedure for detecting lac+ Salmonella mixed with lac+ E. coli consists of touching 12 colonies in succession with a straight wire and then inoculating a peptone iron agar tube. H2S production is apparent from lac+ Salmonella even if 11 E. coli and one Salmonella colony are picked. If a positive peptone iron agar tube is observed, then individual colonies are tested to rule out other strong H2S producers. The true incidence of lac+ Salmonella is unknown because they are not isolated and identified in most laboratories.


Evaluation of the Uni-Yeast-Tek kit for the identification of medically important yeasts. The Uni-Yeast-Tek system, a commercially prepared kit and scheme for the rapid identification of medically important yeasts (Corning Medical), was evaluated in comparison with a conventional procedure in the identification of 623 yeasts. The system permitted the presumptive identification of 99.8% of 436 isolates representing 16 common species commonly isolated in the clinical laboratory. Correct biochemical and morphological analyses were obtained with 48 other species, but their specific identification required additional data.


Formalinized bacterial "antigens" as a potential infection hazard. It is widely thought that after enteric bacteric have been "formalinized" (treated with an equal volume of 0.6% formalin) for 1 h, the bacteria become "antigens" and are no longer viable. None of the 27 cultures of Salmonella and other Enterobacteriaceae were entirely killed within 1 h after formalin was added, but all 27 were reduced from 10(9) viable cells per ml to less than 10(2) per ml within 7 h. Thus, mouth pipetting of cultures formalinized for only 1 h is a possible infection hazard.


Immunochemical studies of the endocrine cells of the gastrointestinal tract. II An immunoperoxide technique for the localization of secretin containing cells in human duodenum. Endocrine cells containing secretin have been identified in the epithelium lining human duodenum by direct and indirect immunoperoxidase techniques using immune sera raised against pur natural secretin. The techniques were applied to sections of carbodiimide-fixed tissue embedded in polyethylene glycol. Some sections, stained by a modified indirect technique, were processed for electron microscopy; secretin-containing granules were present by ultrastructural preservation was too poor to be of value. The potential advantages of a peroxidase technique over fluorescein-coniugated antisera are discussed.


A clinical trial design avoiding undue placebo treatment. A design is descirbed of a modified placebo-controlled double-blind clinical trial procedure. The design was evolved in attempt to overcome certain problems inherent in the conventional double-blind procedure, in particular the ethical problem of prolonged exposure of the patient to placebo treatment. The modified designs consist of two phases. In the first (open) phase, patients selected according to the normal protocol requirements are given the medication under study for a predetermined time. Patients responding favorably to such treatment then enter a second (double blind) phase during which is tested the null hypothesis that all the favorable effects observed during the open phase are placebo effects. Experience with this clinical trial design in the evaluation of an antianginal agent is briefly described. In this case, the null hypothesis was disproved, and a potent therapeutic action was evidenced.


The effect of glucagon on airway resistance. Nine subjects with obstructive airway disease took part in this double-blind study of the effect of glucagon in relieving bronchoconstriction compared with isoproterenol or isotonic saline. Drugs were administered via an in-line intermittent positive-pressure breathing unit. FEV1, MEF, PEF, and nitrogen washout data were evaluated. Ten minutes after administration of saline, mean FEV1 and MEF values were significantly reduced from baseline levels (P less than 0.05). Compared to saline, isoproterenol was followed by significantly increased FEV1 and MEF values (P less than 0.05) at both 10 and 30 minutes after medication, indicating reduction in bronchoconstriction. Although the 1-mg dose of glucagon was followed by a mean decrease in these parameters, this decrease was less than that seen after saline alone.


Cardiorespiratory response to a new isoquinoline derivative in critically III patients. NC 7197, a new N-substituted tetrahydroisoquinoline derivative, was given in doses of 0.2 mg/kg body weight on 26 occasions to a series of 23 critically ill postoperative and posttraumatic patients who had been in moderate or severe degrees of shock. This agent was observed to improve pressure-flow and oxygen-transport variables, including increases in cardiac index, mean arterial pressure, central venous pressure, both left and right ventricular stroke work, central blood volume, systemic vascular resistance, oxygen availability, arteriovenous oxygen content difference, and oxygen consumption, and decreases in mean transit time and pulmonary vascular resistance. Previous studies on critically ill patients have suggested that these are the most commonly desired therapeutic actions for this type of patient. The agent has pronounced inotropic effect with minimal chronotropic effects, but with higher doses, chronotropic effects as well as alpha blocking effects may occur. The optimal effects may be obtained by adjusting the dose to an appropriate therapeutic range. It is concluded that, in the dose used, this agent produced both alpha and beta adrenergic actions in critically ill patients.


Metiapine: a double-blind comparison with chlorpromazine in acute schizophrenic patients. Sixty newly admitted acute schizophrenic patients were randomly assigned to a double-blind trial of metiapine with a maximum dose of 450 mg per day versus a maximum dose of 450 mg per day versus a maximum daily dose of 900 mg chlorpromazine per day. At the conclusion of the study, 21 patients in each group showed marked to moderate improvement. There were significantly more marked improvers in the metiapine group then the chlorpromazine group on the Physician's Posttreatment Global Impression. Evaluation by analysis of covariance of the Brief Psychiatric Rating Scale showed a significant difference between treatment groups favoring chlorpromazine on the item of blunted affect. The spectrum of side effects was similar in the two groups, except for six patients treated with metiapine who displayed tachycardia on the EKG. This pulse elevation was reflected in the group data and is probably dose related. In conclusion, both drugs appeared to be equally efficacious in the treatment of newly admitted acute schizophrenic patients.


Correlation of serum creatinine concentration and amikacin half-life. The half-life of amikacin in serum has been measured following the administration of a single intravenous injection of 7 mg/kg in nine adult patients with varying degrees of renal function impairment and in four patients with normal renal function. A linear relationship between the half-life and the serum concentration has been found, suggesting that half-life of amikacin in serum can be calculated by multiplying the serum creatinine (in mg/100 ml) by 3.


Variability in mineral and trace element content of dairy cattle feeds. Trace element content of feeds is extremely variable compared to total digestible nutrients or protein. Differences are wide between low and high values for many trace elements within a given type of feed. Coefficients of variation for forages range from 42 to 100%. Summary data are given for both major and trace elements. Problems in supplementation are discussed. Amounts for some elements are skewed with relatively few samples around the mean and over 60% below the mean. Suggested mineral allowances for dairy cows are listed. Under current supplementation, zinc is the trace element most likely to be limiting and manganese the least likely. Iron, copper, cobalt, and iodine may be limiting in some cases. Needs of research and applied nutrition are presented.


New concepts and developments in metabolism and homeostasis of inorganic elements in dairy cattle. A review. Major routes of homeostatic control animals use to adapt to widely variable intakes of minerals and the necessity of keeping tissue content of functional forms relatively constant are changes in: (1) percentage absorbed, (2) urinary excretion, (3) tissue deposition in harmless or mobilizable reserve forms, (4) secretion into milk, and (5) endogenous excretion via feces. The importance of each varies greatly among elements. Changes in absorption are of major importance with calcium, iron, zinc, and manganese but not with cadmium or iodine. Urine is a major control route for magnesium, fluorine, selenium, iodine, sodium, chlorine, and potassium. Milk iodine varies almost directly with intake. Tissue deposition and withdrawal are key routes for iron, copper, fluorine, and calcium. Endogenous (metabolic fecal) excretion is crucial in manganese homeostasis. Biochemical details of most homeostatic control mechanisms have not been established. Apparently changes in body tissues control percentage absorption of several elements, including zinc, at the intestine which is the control site. Other major factors which may affect metabolism of several elements include chemical form, whether the elements include chemical form, whether the element is absorbed or injected, and genetic differences among animals. Several common pitfalls and special research problems are discussed. New research indicates that silicon, vanadium, nickel, tin, and fluorine are probably essential.


Selenium in ruminant nutrition: a review. The early interest in selenium related primarily to its toxicity, but since 1957 the element has been recognized as a dietary essential. The dietary requirement for selenium by most species is about .1 ppm. Deficiencies of selenium in cattle and sheep have been confirmed under natural grazing conditions in many countries of the world. Overt signs of inadequacy such as white muscle disease (nutritional muscular dystrophy) occur primarily in young calves or lambs born to selenium deficient dams. Infertility has increased in ewes grazing pastures low in selenium. In general, signs of deficiency have not occurred in older animals such as finishing beef cattle and lactating dairy cows. Subclinical deficiencies of selenium are not determined easily, however, and thus an inadequacy of the element may be limiting maximum animal performance under certain circumstances of drylot feeding. The current nutritional status of ruminant animals in many geographical areas and involving various feeding programs with this element has not been established. The recent widespread deficiency problems with nonruminants suggest that such an assessment should be made. Concentration of selenium in tissue, particularly in the liver, has been used in establishing selenium status of the animal. With lambs glutathione peroxidase activity in certain tissues may be a more accurate indicator of selenium adequacy than is selenium content of the tissue. Supplemental sodium selenite and sodium selenate by either oral administration or parenteral injection have prevented clinical signs of selenium deficiency and animal losses in both ruminant and nonruminant animals. Heavy pellets containing elemental selenium for placement in the rumen have proved effective. In general, organic forms of selenium are absorbed more readily by animals than are inorganic compounds. The dietary requirements for selenium and its metabolism are influenced by many nutrient interrelationships, including its interactions with sulfur, lipids, vitamin E, proteins, amino acids, and several microelements. The Food and Drug Administration gave approval in 1974 for the oral administration of supplemental selenium as either sodium selenite or sodium selenate to certain classes of swine and poultry. Similar approval in the United States for ruminants will require additional information, particularly with regard to the influence of dietary intake on concentrations of selenium in tissue and milk in beef and dairy animals.


A historical review of complete denture impression materials. The history of complete denture impression procefures has been influenced largely by the development of impression materials from which new ideas and techniques arose. Apparently, some procedures have been devised solely for the promotion of certain impression materials. For the most part, however, impression materials have been developed to accomplish specific goals and, at the time at least, were considered desirable for the purpose.


Dental consideration for the child with cleft palate. The dentist's role in the care of the child with cleft palate involves his delivery of the examination, restorative and preventive procedures, and prosthetic, orthodontic, and orthopedic therapy. The practitioner is urged to enthusiastically and intelligently render treatment to these children to the full extent of his capabilities. It also must be remembered that because of the nature of the defect, children with clefts frequently are under demanding therapy from many specialists over their years of growth and development. We must not neglect our obligation to these individuals, but priorities must be taken into consideration for the overall best interest of the patient.


Experimental production of granulomatous pneumonitis. Comparison of immunological and morphological sequelae with particulate and soluble antigens administered via the respiratory route. Rabbits were sensitized with either a soluble protein antigen (BSA) or a particulate thermophilic actinomycete antigen (Micropolyspora faeni) via the respiratory route, followed by monitoring of sequential morphologic changes and the humoral plus cellular immunologic response. Primary respiratory tract sensitization with BSA resulted in a humoral anti-BSA response, Arthus and delayed skin reactivity, and in some cases specific antigen-induced alveolar macrophage migration inhibition, all in the absence of pulmonary lesions. Lesions characterized by mild multifocal perivascular mononuclear cell infiltrates in the lungs developed only after secondary BSA aerosol challenge. In contrast to these findings, "primary" respiratory tract sensitization with M. faeni particulate antigen in saline solution resulted in the gradual development of extensive and progressive pulmonary interstitial and alveolar mononuclear cell infiltrates. These lesions were uniformly associated with specific serum precipitating antibody and delayed skin reactivity. Alveolar macrophage migration was significantly inhibited by Micropolyspora faeni in virtually of these animals. These results, while not excluding a primary irritant effect or Type II or III alergic tissue injury, suggest a role for delayed (cell-mediated) hypersensitivity in the pathogenesis of particulate actinomycete-induced pulmonary lesions. They also indicate that primary immunization with soluble purified protein antigens via the respiratory route can lead to systemic humoral and cell-mediated immunity without production of pulmonary lesions.


Studies on immune competence in the rat: changes with age, sex, and strain. Reticuloendothelial capacity (determined by colloidal carbon clearance) and cell-mediated immunity (determined by xenograft skin grafts and macrophage migration inhibition in vitro) were studied as a function of age for the first time in male and female Sprague-Dawley rats. The results of all three tests in the female rat indicated that maximal immune competence was reached at the onset of puberty (4 weeks) and, depending on the immune response, immune competence declined significantly with age (4 to 96 weeks). In the male Sprague-Dawley, a similar pattern was found in two out of the three tests (colloidal carbon clearance, xenograft skin grafts). Macrophage migration inhibition in the male was unaffected by age (4 to 40 weeks). Cell-mediated immunity (xenograft skin grafts) was also studied in male and female rats of another strain (Long Evans) as a function of age. Maximal competence occurred at the onset of puberty and declined thereafter.


Effect of Cs137 on immunological reactivity (review of literature). An important role of Cs137 as a new ecological factor was shown by analyzing the works of 31 authors. This radioisotope may at present be deceted in the organisms of all the inhabitants of this planet. The migration of Cs137 along the chain lichen-deer-man leads to its accumulation in the organism of human subjects living in the Extreme North and utilizing venison in their diet. Although the high sensitivity of immunological reactions to various unfavourable environmental factors is well known, the materials on the effect of incorporated Cs137 on immunity are scanty, Experiments on animals have shown changes in factors of nonspecific immunity (phagocytic reaction of blood neutrophils, bactericidal activity, lysozyme and complement titres of blood serum) and specific immunity (formation of antiviral antibodies). The blood of animals injured by the isotope displays complete and incomplete autoantibodies. A dependance between the immunobiological changes and the dose absorbed by the organism was demonstrated. The entry of CS137 into the organism of the inhabitants of the Extreme North who use venison in their diet did not, with the absorbed dose equalling up to 50 Mrem per year, lead to changes in their immunological reactivity.


Study of rickettsioses in Slovakia. II. Infestation of fleas and mites in mole nests in some localities in Central Slovakia with C. burneti and Rickettsiae belonging to the spotted fever (SF) group. Fleas and mites obtained from 115 mole nests in Central Slovakia from an area where Q fever and rickettsiosis due to rickettsie of the SF occur, from the border of this area and apart from it, were tested for infestation with rickettsiae by the method of isolation of rickettsiae on chick embryo yolk sacs, by the method of detection of rickettsiae on smears from the arthropods using immunofluorescence, by the method of exposure of albino mice and Apodemus flavicollis to mole nests and by the method of inoculation of suspension from the arthropods to albino mice. In the latter two methods, infestation of the arthropods was assessed according to the formation of antibodies in the mice. It has been found that fleas and mites in all three areas under test are infected with C. burneti and with rickettsia of the SF group. C. burneti was currently detected in the focus of rickettsioses and in the localities situated in its borders while only one case was observed apart from the focus. Rickettsiae of the SF group were found in fleas and mites in all areas tested showing no greater percentual differences. The method of detection of rickettsia in smears from the arthropods using the immunofluorescence technique and antibody response in mice inoculated with infected arthropods was found to be the most effective in these studies. On the basis of the obtained results the authors believe that mites and fleas living in mole nests participate in the circulation of both species of rickettsiae in nature in the transfer of rickettsiae among small mammals. The question whether these arthropods are a reservoir, a biological or a mechanical vector, still remains open.


Some immunochemical and chemical aspects of S and R Shigella dysenteriae 1 endotoxins. Endotoxins of S and R forms of Shigella dysenteriae 1 were prepared by NaCl-Na citrate extraction, purified by gel chromatography on Sephadex G 200 and on Sepharose 4B and subjected to immunochemical and chemical analysis. The toxins contained 25--30% of lipids, 40--50% of carbohydrates and 14--24% of protein. The lipid and protein moieties of the lipopolysaccharide-protein complexes exhibited no significant difference, whereas the sugar moieties differed markedly (both qualitatively and quantitatively), in relation to the growth form of the culture. The lipid moiety, which consists at least of 22 fatty acids, has the greatest relative content (approx. 50%) of behenic acid, 22:0, and palmitic acid, 16:0 (approx. 11%). In the protein moiety, at least 16 amino acids were determined; these amino acids were identical in both endotoxin types, but their total content was higher in the R form, giving an R:S ratio of 1.7 +/- 0.2. The sugar moiety consists of galactose, glucosamine and either rhamnose (in S endotoxin) or aldoheptose (in R endotoxin). The difference of the chemical composition of the sugar moiety is believed to account for the diametric difference in the immunochemical character, in particular the different behaviour in the electric field, of both endotoxin types. The average content of 3-deoxy-D-manno-2-octulosonic acid was determined as 0.5% for both S and R endotoxin. Trace amounts of O-phosphorylethanolamine were found. Individual aspects of the chemical and immunochemical analysis are discussed in detail.


The effects of chemotherapeutics on the species streptococcus in vitro. The authors studied the sensitivity of some rather recent products--flucloxacillin, doxycyclin, clindamycin and cotrimoxazol--in correlation with classical penicillin. If therapy by means of classical penicillins is unsuitable, clindamycin and the semi-synthetic penicillin flucloxacillin appear to be a further alternative and the most suitable chemotherapeutic in streptococcal infections.


Immunologic functions of isolated human lymphocyte subpopulations. VI. Further characterization of the surface Ig negative, E rosette negative (null cell) subset. Sephadex G-200 anti-human Fab column chromatography and rosette depletion techniques were used to isolate three distinct subpopulations of human lymphocytes: 1) T cells which are surface Ig negative and E rosette positive, 2) B cells which are surface Ig positive and E rosette negative, and 3) a "Null" cell population which is both surface Ig negative and E rosette negative. All populations were analyzed for their capacity to develop surface Ig and synthesize Ig in vitro. Greater than 50% of cells in the Null cell population developed surface Ig by day 3 of cell culture. Furthermore, in vitro, the Ig content of the Null cell population, as well as their capacity to secrete Ig in culture, becomes comparable to that produced by B cells. In contrast, cultured T cells neither develop surface Ig nor secrete Ig in culture. These data strongly support the idea that the Null population contains a subset of Ig-producing B cells.


Ly antigens: markers of T cell function on mouse spleen cells. By the use of Ly antisera and complement it is possible to remove subpopulations of mouse T cells from spleen cell suspension. It is shown that these Ly antisera are specific for the Ly alleles carried by the cells. Helper cells from primed or unprimed mice and cells which respond to Con A express Ly-1 antigen but little or no Ly-2 antigen (Ly-1+ phenotype) whereas cells which respond to PHA express both Ly-1 and Ly-2 antigens (Ly-1+2+ phenotype).


Oxisuran and immune reactions: mediation of oxisuran action by the adrenal glands. Oxisuran was tested in a TAR system and for the DH on SRBC. Besides immunosuppressive properties in the TAR and DH also mentioned by other authors, stimulation was found after prolonged administration. No effect of oxisuran on the humoral response was observed. The action of oxisuran was suggested to be indirect, effected by stimulation of the PAG system. Adrenalectomy of mice made animals non-liable for oxisuran action measured in the TAR assay. Oxisuran caused an increase of the corticosterone plasma level with a peak after four daily injections. This was paralleled by a peak in adrenal gland weight and a minimum in thymus size. The reduction in these effects after five injections (tachyphylaxis) suggest that a feedback mechanism is involved. Comparison of thymus weights after oxisuran and corticosterone administration indicates that a daily dose of 100 mg oxisuran/kg corresponds with 1.5 mg corticosterone/kg. The effects of oxisuran in the TAR and on the DH and the feedback phenomenon could be imitated with 1.5 mg corticosterone/kg. The mononuclear phagocyte has been proposed as the main target cell of oxisuran action, mediated by the PAG system.


Histocompatibility and T-B cell cooperation in mouse radiation chimeras. Cooperative interaction between histocompatible as well as histoincompatible T and B cells in vivo was studied with B cell-bearing syngeneic radiation chimeras receiving syngeneic, semiallogeneic, or allogeneic A and T cells in various combinations. The results indicated the following: i) Histoincompatible T and B cells normally did not cooperate successfully for generation of antibody-forming cells. ii) Semiallogeneic (C3BF1) T cells cooperated successfully with parent-type (C3H) B cells developed in parent-type syngeneic chimeras (C3H/C3H), whereas parent-type (C3H as well as C57BL) T cells failed to cooperate with F1 (BC3F1) B cells developed in F1 syngeneic chimeras (BC3F1/BC3F1). iii) T cells obtained from C57BL/C3H or C57BL/C3BF1 chimeras, which were most likely donor (C57BL)- derived, cooperated successfully with C3H-derived B cells developed in C3H/C3H chimeras. iv) Evidence was obtained suggesting that stimulation of antibody response by allogeneic effect in the absence of syngeneic or semisyngeneic helper T cells did not take place in this experimental system. v) With the use of congenic resistant strains, it was shown that alloantigens controlled by H-2 loci, in particular by the K-I region of this gene complex, constituted the barrier of cooperative interaction between histoincompatible T and B cells. vi) Cooperation between H-2 compatible, non-syngeneic T and B cells was also disturbed in varying degrees depending on the strain combinations, thus indicating that cell surface antigens controlled by non-H-2 loci also had a significant role for the cooperative interaction between T and B cells. Problems associated with these findings were discussed.


Rapid isolation of antigens from cells with a staphylococcal protein A-antibody adsorbent: parameters of the interaction of antibody-antigen complexes with protein A. The Cowan I strain of the bacterium Staphylococcus aureus has been used as an adsorbent for antibodies complexed with radiolabeled antigens from cell lysates. This application is advanced as a superior alternative to other methods of immune precipitation for the isolation of antigens. It exploits the high adsorption capacity for IgG molecules by protein A molecules on the cell walls of certain strains of staphylococci, along with the advantageous sedimentation properties of the bacteria. The interaction of immune complexes with the adsorbent was defined initially using a model system of bovine serum albumin with a high excess of rabbit anti-bovine serum albumin antibodies (IgG). The uptake of immune complexes under these conditions was extremely rapid, occurring within seconds, whereas maximum binding of free IgG was much slower. In addition, once bound the complexed antigen could not be displaced from the adsorbent either by large amounts of normal IgG or by extra free antibody. Antigen could be eluted almost completely from the inert adsorbent for analytic or preparative purposes with a variety of solvent systems, such as the detergent SDS in combination with urea and high temperature, and neutral salts with strong lyotropic salting in properties. The efficacy of the protein A-antibody adsorption technique was tested in direct comparisons with a conventional double antibody precipitation method for the isolation of mouse lymphocyte IgM. The bacterial adsorbent not only had a distinct advantage in speed of antigen isolation, but analyses by polyacrylamide gel electrophoresis in SDS also revealed consistently higher antigen recoveries, lower levels of background radioactivity, and an absence of other cell components which may nonspecifically bind to and complicate analyses using conventional immune precipitates.


Antigen suppression of the in vitro development of plaque-forming cells to autologous erythrocyte antigens. Peritoneal cell cultures from NZB and C57BL/6 mice develop large numbers of PFC directed against antigens present on bromelain-treated isologous erythrocytes. The development of these autoimmune PFC can be suppressed by the addition of small numbers of BrMRBC at the start of the culture period. The possibility that the development of the plaque is prevented by the presence of antigen in vivo is discussed.


Chemotaxis under agarose: a new and simple method for measuring chemotaxis and spontaneous migration of human polymorphonuclear leukocytes and monocytes. A variety of methods have been devised for the study of spontaneous and directed cell migration. Among these, the membrane filter method introduced by Boyden in 1962, with its more recent modifications, has become the technique of choice for studies of leukocyte migration in vitro. This method, however, cannot be applied without alteration to studies of chemotaxis and spontaneous migration of cells of different types. We describe in this report a new and simple method for studying human leukocyte chemotaxis, in vitro, which is based upon migration of cells under agarose gel. This method has application to both polymorphonuclear leukocytes and monocytes, permits measurement of both chemotaxis and spontaneous migration, requires fewer cells per test, and is rapid, simple, reproducible, and inexpensive to set up.


Desensitization: effects on cutaneous and peritoneal manifestations of delayed hypersensitivity in relation to lymphokine production. Guinea pigs exhibiting delayed hypersensitivity may be desensitized by a single large dose of antigen administered intramuscularly. In the present experiments, desensitization with a soluble protein such as egg albumin (EA) or bovine gamma-globulin (BGG) was nonspecific in that they suppressed both cutaneous reactivity and the macrophage disappearance reaction (MDR) to unrelated antigen in doubly immunized animals. In contrast, myobacterial antigen, at the dose studied, showed limited specificity in that it could suppress the MDR but not a skin test to an unrelated antigen. Induction of an MDR was shown to be associated with the appearance of macrophage migration inhibitory factor (MIF) and chemotactic activity in the peritoneal exudate fluid. Pretreatment with desensitizing doses of mycobacteria prevented the EA-induced appearance of MIF in the peritoneal fluids. In contrast, chemotactic activity could still be recovered, even though the MDR was suppressed. Mycobacteria functioned as a specific desensitizer not only with respect to cutaneous reactivity, as stated above, but also with respect to the production of chemotatic factor by peritoneal exudate cells. In contrast, mycobacteria functioned as a nonspecific desensitizer with respect to both the MDR and MIF production. These results suggest that the MDR may be an in vivo manifestation of MIF activity, whereas the cutaneous delayed hypersensitivity reaction may be more dependent upon chemotactic activity. These observations reported here, taken in conjunction with previously described in vitro studies, suggest that desensitization is a complex phenomenon which may be the result of several different mechanisms acting separately or in concert. The apparent discrepancies in the literature as to whether or not desensitization is a specific process would appear to arise from differences in the experimental model and the particular antigen used.


Interrelationships of surface immunoglobulin and Fc receptors on mouse B lymphocytes. Receptors for the Fc portion of immunoglobulin (Ig) molecules have been detected on mouse B lymphocytes by an immunofluorescence technique, employing immune complexes of fluorescein-conjugated KLH and rabbit anti-KLH antibody. At 37 degrees C, membrane-bound complexes rapidly undergo capping and clearing from the surface. Modulation of Fc receptors does not alter the amount of distribution of surface Ig, indicating that these two molecules are independent moieties. However, capping of surface Ig by intact or pepsin-digested anti-Ig antibody leads to co-capping of Fc receptors. These results suggest that ligand binding to surface Ig induces some alteration which allows the Ig to enter into an association with Fc receptors.


Functional deficiency of splenic adherent cells in New Zealand black mice. New Zealand Black (NZB) mice hyporespond after in vitro immunization to sheep erythrocytes but not after in vivo immunization. The difference between in vitro and in vivo immunization was found to involve a non-antigen-specific change in the spleen which occurs in vivo soon after priming. Adherent spleen cells from young NZB or control strain mice were compared in their ability to cooperate with nonadherent cells in the induction of a primary immune response to sheep erythrocytes in vitro. The results support the hypothesis that there is a functional deficiency of adherent cells in the spleens of unprimed NZB mice.


Enumerating immunoglobulin-secreting cells among peripheral human lymphocytes. A hemolytic plaque assay for a B cell function. Cells bearing immunoglobulin (Ig) can be enumerated by current methods, but cells secreting Ig (with unknown antibody specificity) can not. By using a reverse plaque-forming cell assay, we counted the Ig-secreting cells in the blood of nonimmunized individuals. Isolated human lymphocytes were plated in gels together with erythrocytes coated with purified antibody to human Ig. After treatment with anti-Ig antibody and complement, the Ig-secreting cells formed hemolytic plaques. In 10 normal individuals, 1.2 +/- 0.4% of the plated mononuclear cells formed plaques; in an individual tested on 7 different days during 3 months, 1.1 +/- 0.2% of the cells formed plaques. From the number of mononuclear cells in the blood, we calculated 22 +/- 8 Ig-secreting cells per mm3 of blood. Enumerating Ig-secreting cells is a new direct assay for a B cell function and need not correlate with quantitating serum Ig. Thus, this assay should be useful for studying Ig-secretion in normal and altered states.


A new immunoassay based on fluorescence excitation by internal reflection spectroscopy. A new immunoassay technique is described which uses totally internally reflected light to excite the fluorescence of fluorescein labeled antibody which has become bound to a hapten--protein conjugate absorbed on a quartz-plate in the antibody solution. The presence of any free hapten in solution reduces the amount of antibody free to bind to the surface and thus reduces the fluorescence signal. Measurement of the decrease of the fluorescent signal then gives a measure of the concentration of free hapten present. The technique is simple, fast and has high intrinsic sensitivity and specificity. It has been demonstrated for phenyl arsonic acid and morphine. Free morphine at a concentration of 2 X 10(-7) M is readily detected.


The L.A.I. microtest: a rapid and sensitive precedure for the demonstration of cell-mediated immunity in vitro. A new microtest for cell-mediated immunity is described, which is based on the elaboration of a diffusible factor from sensitized lymphocytes following contact with specific antigen. The factor inhibits the adherence of neighbouring leucocytes to plastic surfaces. Production of the factor is ablated by pretreatment of lymphocytes with Theta-antiserum. It is suggested that the factor may be a new lymphokine, leucocyte adherence inhibition factor (LAIF).


Clinical trials with Alice strain, live, attenuated, serum inhibitor-resistant intranasal influenza A vaccine. Two clinical trials with Alice strain intranasal influenza vaccine were performed. In study no. 1 (utilizing random selection and double-blind control), 50 subjects received a bivalent inactivated influenza vaccine intramuscularly, 99 subjects received Alice strain vaccine intranasally, and 50 subjects received a placebo intranasally. No symptomatology could be attributed to the intranasal route of immunization. Convalescent-phase geometric mean titers of hemagglutination inhibition antibody were higher after intramuscular vaccination; seroconversion occurred in 16 or 17 recipients of the Alice strain, with initial titers of less than 1:8. Clinical and virologic surveillance for 20 weeks after vaccination revealed no influenza A illnesses in participants of the study. In study no. 2, 75% of the subjects with initial nasal antibody titers of less than 1:3 developed measurable nasal antibody after receiving Alice strain vaccine.


Group B streptococcus in a general hospital. Eighty-six percent of 707 beta-hemolytic streptococci isolated in a general hospital and excluded by presumptive tests from groups A and D were identified serologically as group B. More than 70% of the group B isolates were from urine cultures, the female genital gract, or newborn infants. Types III and II were the most common group B serotypes from most sources. However, types Ia, Ib, and Ic were more commonly isolated from the respiratory tract than from other sites, and type III was responsible for most serious neonatal infections. All group B streptococci were sensitive in vitro to comparable levels of penicillin G, ampicillin, and cephalothin and were highly resistant to kanamycin. Seventy-two percent were resistant to tetracycline but only 1%-2% to erythromycin, clindamycin, and chloramphenicol. Despite consistent sensitivity to penicillin G, the minimal inhibitory concentrations were significantly higher for group B than for group A streptococci.


Prevalence of toxigenic and invasive strains of Escherichia coli in a hospital population. The pathogenesis of gastrointestinal infections caused by Escherichia coli has been attributed to the ability of some strains to produce exotoxins (enterotoxins) or to invade the intestinal mucosa directly. To investigate the possible role of invasiveness and of production of toxin in the pathogenesis of nonenteric E. coli infections, we studied E. coli isolated from 152 patients with urinary tract infections, bacteremia, or both. None of the isolates from urine or blood exhibited invasiveness in the guinea pig eye or produced toxin in tissue culture or in infant mice; only one patient was a gastrointestinal carrier of toxin-producing E. coli. We concluded that, in the population of this study, production of toxin and invasiveness were not important in the pathogenesis of most urinary tract infections or bacteremia caused by E. coli, and that gastrointestinal colonization with such organisms was uncommon.


The complement system in bullous pemphigoid. III. Fixation of C1q and C4 by pemphigoid antibody. By in vitro complement immunofluorescent staining methods, 46 serum samples from bullous pemphigoid patients with titers of antibasement-membrane-zone antibodies of 320 or greater were tested for their ability to fix C1q, C4, and C3. All three staining reactions were positive with 23 of the samples; 21 samples yielded negative reactions. With one sample, the C1q and C3 staining reactions were positive but the C4 reaction was negative; one other sample gave a positive C3 staining reaction only. Absorption of anti-C1q, anti-C4, and anti-C3 with C1q, C4, and C3, respectively, blocked the specific in vitro complement staining. Therefore, bullous pemphigoid antibodies of the IgG type appear to be capable of activating the  "classical" complement pathway.


Experimental aspergillus endocarditis in rabbits. Aspergillus endocarditis in man usually occurs on prosthetic cardiac valves and gives rise to large vegetations which embolize easily producing peripheral organ infarction and infection. Blood cultures are usually sterile and the disease is difficult to cure with antimicrobial agents. Aspergillus endocarditis was studied in rabbits to determine the course, degree of fungemia, and response to treatment with amphotericin B (A), 5 flucytosine (5 FC) or A + 5 FC. Polyethylene tubing was introduced into the left ventricle through the carotid artery and 24 hours later animals were inoculated with 10(4) to 10(7) spores of a strain of Aspergillus fumigatus. Large occlusive vegetations developed on the aortic valves. Spontaneous mortality reached 67 per cent after 3 days. Despite large aggregates of mycelia seen beneath a layer of amorphous material on microscopic sections, vegetations contained only 10(3)  to 10(5) colony forming units (CFU) of aspergilli per gram, suggesting the aspergilli in tissues were clumped. Disseminated infection involving kidney, lung, liver, spleen, and brain occurred. Animals without intracardiac tubing which received the same inoculum of spores did not develop endocarditis, but showed evidence of disseminated infection. Blood after 24 hours of infection grew aspergilli only when large volumes were cultured and then only a small fraction of the total volume of blood obtained for culture yielded aspergilli, suggesting that the aspergilli in blood were clumped. Sterile vegetations in the absence of an intracardiac catheter were resistant to infection with aspergilli, but once established, infection with aspergilli persisted on vegetations despite removal of the catheter. Treatment of infected animals with A (1 mg. per kilogram), 5 FC (25 or 50 mg. per kilogram) or A + 5 FC daily intraperitoneally, significantly lowered the number of CFU per gram of vegetation.


Fatal haemorrhage from the innominate artery complicating tracheostomy. A fatal haemorrhage of the innominate artery complicating tracheostomy for obstructive carcinoma of the larynx is reported. The possible mechanism of the rupture is discussed and methods of management are suggested.


Immunofluorescence studies on amphibian myoblast differentiation. Differentiating myoblasts from urodele amphibians were cultivated in vitro and treated by immunofluorescence techniques and (or) inhibitors of RNA and protein syntheses. These experiments lead to the conclusion that the differentiation of these cells is directed by long-lived m-RNAs which are already present in morphologically undifferentiated cells and may act for at least 6 days. Contrary to observations on cultivated myogenic cells from other groups, the fusion of urodele myoblasts is not a prerequisite for a normal and functional differentiation (contractions) since isolated myoblasts differentiate quite normally. The appearance and further evolution of myosin and actin occur synchronously in this biological system.


The developmental capacity of nuclei transplanted from keratinized skin cells of adult frogs. Nuclei from keratinized skin cells of adult Xenopus foot-webs have been transplanted to enucleated eggs of the same species. 2. The cells used to provide donor nuclei were obtained as a monolayer outgrowth from cultured foot-web explants. When explants were cultured without plasma for 3 days, over 99-9% of the outgrowth cells contained keratin as revealed by the binding of monospecific fluorescent antibody prepared against purified Xenopus keratin. Nuclei were transplanted from cells which had been cultured for 31/2 days. 3. None of the first transfer embryos developed as far as tadpoles. Eleven clones of embryos were prepared from the nuclei of partial first-transfer blastulae by use of serial nuclear transplantation. Eight of these clones contained swimming tadpoles with functional muscle and nerve cells, and six clones contained tadpoles with beating hearts, well differentiated eyes, and other organs. 4. To prove that the nuclei of nuclear-transplant tadpoles were derived from the transplanted skin cell nuclei and not from a failure of ultraviolet light to inactivate the recipient egg nucleus, 1-nu skin cell nuclei were transplanted to eggs laid by 2-nu frogs. Several advanced tadpoles from six clones were analysed for nucleolar and chromosome number and found to be 1-nu diploids. 5. The six clones of advanced tadpoles which were proved to carry the donor nuclear marker represent six first-transfer nuclei in a total sample of 129 skin cell nuclei originally transplanted. The probability that all six nuclei were derived from the 0-1% of the donor cell population not proved to contain keratin is less than one in 10(10). 6. We conclude that cell specialization does not involve any loss, irreversible inactivation or permanent change in chromosomal genes required for development.


Intraosseous neurilemmoma of the cervical spine causing paraparesis and treated by resection and grafting. A neurilemmoma presented as an expanding lesion of the bodies of C6 and C7 vertebrae and caused local neurological signs together with a spastic paraparesis. This tumour was treated by preliminary posterior fusion, followed by its complete removal via an anterior approach and stabilization by anterior spinal fusion. Other cases in the literature are reviewed and discussed.


Blood flow in normal and injured monkey spinal cord. The authors used indicator fractionation techniques to determine blood flow in normal and bluntly traumatized spinal cords of Macaca rhesus monkeys. Normal flow rates were determined for several levels of spinal cord as well as differential values for white and gray matter from representative areas. Flow rates in traumatized tissue, obtained at several different time intervals up to 4 hours after injury, demonstrated marked differences in regional perfusion of the white matter and gray matter after trauma. Gray matter perfusion was nearly obliterated while white matter blood flow persisted and in fact was higher than uninjured controls. The findings do not support the concept of ischemia as a factor in white matter failure. If toxic pathobiochemical alterations are induced by trauma, it may be possible to reverse these changes by exploiting the preserved white matter blood flow for chemotherapeutic intervention.


Our underpinnings: a bicentennial view. The 1975 Harvey Cushing oration. The author describes the emergence of the liberal traditions which is the foundation of the political and economic systems in this country and considers policies that may affect our social and economic future.


Systemic hypotension in neurosurgery.

Systemic hypotension in neurosurgery. The authors review the intraoperative use of elective hypotension to reduce the probability of hemorrhage, to increase pliability of the aneurysmal sac for ease of clip application, and to control hemorrhage. The optimum agent and techniques for lowering systemic blood pressure remain controversial, but trimethaphan, sodium nitroprusside, and halothane have been found most useful. When cerebral blood flow falls below the brain's capacity to autoregulate, distinct time-related alterations occur biochemically and histologically. The profile of prolonged reduced adenosine triphosphate (ATP), low phosphocreatine, low glucose, and elevated lactate and lactate/pyruvate ratio is associated with swelling of perivascular astrocytes and "blebbing" of vascular endothelial cells with subsequent cerebral damage. To prevent permanent alteration it is desirable to observe time constraints and to employ other means of protection such as hypothermia, although the authors believe the latter unnecessary for short hypotensive periods. It has been proposed, but not substantiated, that anesthetics which depress rate of cerebral oxygen consumption but do not affect cerebral ATP level protect the brain from hypotension. Several investigations suggest that halothane, a vasodiltor, satisfies the safety requirement. The most prominent contraindication to halothane, however, is elevation of intracranial pressure. At present hypotensive surgery for aneurysmorrhapy is usually performed when intracranial pressure has returned to normal. Experimentally the electroencephalogram has been observed to show alterations prior to biochemical parameters for following brain vulnerability, so that it conceivably could be an effective monitoring technique during prolonged profound hypotension.


Acupuncture analgesia in dentistry: an analysis of studies from the People's Republic of China. Studies conducted on the use of acupuncture analgesia for dental procedures in the People's Republic of China have not provided sufficient evidence to indicate that acupuncture analgesia can replace conventional drugs as the preferred anesthetic. However, studies currently in progress in China and in the United States may be successful in finding ways to reduce the failure rate and in determining the operative benefits of acupuncture.


Possible nosocomial transmission of group B streptococci in a newborn nursery. Within a six-day period in March, 1974, three infants born at a hospital in central Arkansas developed meningitis caused by group B, type III Streptococci. Three factors suggested nosocomial transmission of the organism in the nursery: (1) the three infants were born in a six-day period, (2) four weeks after their infants' births, none of the parents had positive cultures for group B streptococci, and (3) 31% of infants born in the hospital in March were colonized with group B, type III streptococci, while in April, after control measures in the nursery were instituted, only 2% of infants were colonized with this type (p less than 0.0002). Colonized infants were treated with penicillin, but follow-up cultures at two and six weeks showed that half the infants tested were still colonized. The number of personnel colonized with group B streptococci was not significantly different in personnel exposed to infants when compared with those that were not, and handwashing and environmental cultures were negative for group B streptococci. The results of this investigation give additional support to the concept that nosocomial transmission of group B streptococci can occur and may be effectively interrupted by control measures in the nursery.


Treatment of Candida peritonitis by peritoneal lavage with amphotericin B. A 14-year-old girl, who was a renal transplant recipient, developed Candida tropicalis peritonitis during peritoneal dialysis and immunosuppressive and broad-spectrum antibiotic therapy. Therapeutic cure of the peritonitis followed a ten-day course of amphotericin B administered solely by peritoneal lavage.


Congenital rubella.

Congenital rubella. The original concept of the rubella syndrome as a triad of abnormalities affecting the eye, heart, and hearing organs has changed dramatically in the past 30 years. This paper describes the various clinical manifestations of congenital rubella now recognized and the varied consequences of rubella virus infection upon the fetus. The pathogenesis of intrauterine rubella is discussed in relation to the immunologic response of the fetus and to possible mechanisms of cell and tissue damage. The need for preventive measures is discussed in relation to the total number of children damaged annually and the importance of multiple defects leading to severe handicaps. Active immunization procedures to prevent congenital rubella defects are reviewed, with comments on the differences between vaccination policies in the United Kingdom and in the United States. The importance of surveillance of congenital rubella defects is emphasized; details of the National Rubella Surveillance Scheme in the United Kingdom are discussed.


Nonspecific enhancers of resistance in man. Nonspecific enhancers of resistance may include (1) viral interference, (2) interferon, (3) interferon inducers, (4) bacterial interference, (5) bacterial products such as Coley's "toxins," endotoxins, or staphylococcal, BCG, and Corynebacterium parvum vaccines, (6) transfer factor, and (7) well-defined chemicals such as dinitrochlorbenzene, levamisole, and vitamin C. These are discussed only as they have been applied to man to learn whether or not they have enhanced his ability to resist infections and growth of tumors. Preliminary studies suggest that a variety of relatively safe and effective nonspecific enhancers may soon be available for clinical use.


Immunologic and virologic studies in the postpericardiotomy syndrome. A prospective, triple-blind study was undertaken to determine whether antiheart antibody or a rise in titer to a virus occurred in patients after intrapericardial surgery and, if so, whether either was related to clinical evidence of the postpericardiotomy syndrome. In 257 patients, AHA in high titer appeared in 62 (24%), all of whom had the syndrome. None of the 102 patients with no AHA had the syndrome. In 137 subjects, a rise in titer to one or more viral agents occurred in 21 of 31 (68%) of those with AHA and PPS. This study suggests that an immunologic response and viral illness are related to PPS.


Rickets then and now.

Rickets then and now. Since the introduction of irradiated ergosterol into our food supply, nutritional vitamin D-deficiency rickets has become an uncommon disease. However, skeletal disorders due to abnormalities of vitamin D function still occur. These disorders can now be classified more exactly into two groups: those in which there is a deficiency of the active metabolite of vitamin D, 1,25-dihydroxyvitamin D, and those in which there is an abnormality of renal tubular function resulting in renal hypophosphatemia despite normal vitamin D metabolism. The various entities of these two groups are described and the theoretical basis of their treatment given.


Failure to protect Mus musculus against Plasmodium berghei with footpad injections of killed parasites incorporated in complete Freund's adjuvant. The stimulation of cell-mediated immunity by the injection of antigen from killed parasites incorporated in complete Freund's adjuvant did not protect Mus musculus from the erythrocytic stages of Plasmodium berghei. Agglutinating antibodies could not be detected, but delayed hypersensitivity was demonstrable. Apparently thymocyte sensitization alone was not sufficient to afford protection.


Thermodilution cardiac output measurement in infants and small children following intracardiac surgery. A modified catheter has been used in conjunction with a thermodilution cardiac output computer for postoperative assessment of cardiac function in infants and children. Because of the small amount of fluid required for each determination and the simplicity of the technique, serial measurements can be done safely. Its use has contributed to the early detection of low output states. It has also proven to be a useful tool for estimating the optimal heart rate in each patient and for assessing the effectiveness of therapeutic measures.


Osseous autografts. II. Histological responses to osseous coagulum-bone blend grafts. Three human intraosseous lesions were treated using osseous coagulum-bone blend as graft material. These sites were surgically removed 6 to 13 weeks after treatment and the blocks prepared for histologic analysis. Periodontal remodeling at the site of grafting was noted in all specimens. This remodeling involved the osseous walls, periodontal ligament, cementum and graft spicules. Both osteoclastic and osteoblastic activities were seen at the borders of the spicules. Exfoliation of spicules was particularly frequent in the six-week specimen. Nevertheless, regenerating of both bone and cementum was actively taking place even in this early specimen and was still evident in the older specimens. Of particular interest was the apparent marked increase in cementogenesis at the graft sites and the variations in parallel or functional orientation of the periodontal ligament in these areas. Significant functional orientation of segments of the periodontal ligament were seenin the early specimens, but not in the latter one. The reason for such variations in ligament pattern is not known at this time.


The effect of an antimicrobial mouthwash on dental plaque and gingivitis in yound adults. The effectiveness of an antimicrobial mouthwash (alexidine, 2-ethylhexyl bisbiguanidine dihydrochloride) in preventing plaque and gingivitis was evaluated in 45 young male adults. In a study using a double-blind cross-over design, subjects received a thorough prophylaxis and refrained from all routine oral hygiene for 2 weeks. During this period, subjects rinsed twice daily with either a treatment (alexidine) or placebo mouthwash. Plaque and gingivitis were assessed on selected teeth on days 2, 7 and 14. The characteristics of plaque that were recorded include: surface area score, dry weight and differential counts of microorganisms. After the 14th day, subjects resumed their regular oral hygiene practices for 3 weeks before starting the second experimental period. Aftter a second prophylaxis, the treatment and placebo groups from the first 2 weeks were crossed over and the procedures followed previously were repeated during the sixth and seventh weeks. The alexidine mouthwash was statistically and clinically effective in decreasing plaque scores and plaque weight, and statistically but not clinically effective in decreasing gingivitis scores. No systemic side effects were observed, but an asymptomatic brown tongue stain was observed in about half of the subjects. There was no evidence to suggest that alexidine disturbed the relative composition of the microorganisms in plague, but there was a suggestion that it decreased the number of microorganisms almost 2-fold when compared with the placebo group.


A new automated interpretation system for the 16PF. A new computerized interpretation system for the 16PF is described. This system is based on the novel concept of attempting to simulate directly the diagnostic report-writing capabilities of a single clinician. Certain considerations regarding the problem of validity in respect to this area are brought up, and the general operation of the system is outlined.


Perception of aggression and overt aggressive behavior. Investigated the relationship between thresholds for perception of aggressive cues and overt aggressive behavior in 86 male undergraduate students. Overt aggressive behavior was measured by the amount of shock the subject attempted to inflict on his presumed opponent. It was found that individuals with low thresholds for aggressive cues expressed less overt aggressive behavior while individuals with high thresholds for aggression expressed more overt aggression. Thus an inverse relationship was found with respect to perceptual recognition thresholds for aggressive stimuli and overt aggressive behavior. The implications of these findings for projective techniques and their relevance to perception as it relates to overt behavior were discussed.


Microbial kinetics of drug action against gram-positive and gram-negative organisms. III: Effect of lincomycin and clindamycin combinations on Staphylococcus aureus and Escherichia coli. The functional dependencies of apparent first-order generation rate constants kapp, of drug-affected cultures on drug concentrations indicate that lincomycin and clindamycin possess the same mechanism of action, which is bacteriostatic, against Staphylococcus aureus. Clindamycin also possesses another mechanism of action, which is bactericidal, at high concentration levels. However, clindamycin possesses only one of the two mechanisms of lincomycin action, which is bacteriostatic, against Escherichia coli. The relative potency of action of a clindamycin-lincomycin combination against Staph. aureus is variable, and the effective ratio ranges between 5:1 and 9:1; the effective ratio against E. coli is fixed at 6:1 over a wide concentration range. This difference is attributed to differences in bioavailability and/or binding characteristics of the drugs for bioreceptors, as a consequence of structural modifications in the drug molecules, and to differences in modes of action in the respective organisms. Mixtures containing equipotent fractions of clindamycin and lincomycin show "equivalence" or "indifference" of effects on Staph. aureus. The combined action of the mixtures can be quantitatively predicted from the separate dose-response curves of either component drug alone. Therefore, it is concluded that clindamycin and lincomycin may bind to the same receptor site that is engaged in microbial protein synthesis to inhibit the generation of Staph. aureus. However, combinations of clindamycin and lincomycin are less active than the a priori equipotent concentration of either drug alone in their action against E. coli, demonstrating unequivocally an antagonism of effects. Furthermore, the degree of antagonism is dependent on the order of addition of the drugs, which is attributed to the possibility that clindamycin and lincomycin bind differently on active and allosteric loci of the same receptor site functionally engaged in protein synthesis in E. coli. A rational approach to the quantification and prediction of combined antibiotic action must, therefore, be based not only on the kinetics and mechanisms of action as well as on the dose-response relationship over a wide concentration range for the separate antibiotics but also on the strain and species of the test organism.


In vitro and in vivo availability of commercial prednisone tablets. A three-way crossover bioavailability study was performed using nine adult male volunteers with three different commercial prednisone tablets. Plasma samples were assayed for prednisolone, the active metabolite of prednisone, by a radioimmunoassay method. Statistical analysis showed significant differences in the rate of appearance of prednisolone in plasma but not in the amount converted to prednisolone. The results suggest that differences in in vivo rates of appearance of prednisolone in plasma correlate with in vitro rates of dissolution.


Opposing responses in sympathetic nerve activity induced by central injections of ouabain. Cardiac glycosides induce changes in activity of peripheral sympathetic nerves. Arrhythmic doses have been suggested to act in the central nervous system to produce these changes, but direct central effects of digitalis on sympathetic discharge have not been documented. Thus, the central action of ouabain on sympathetic outflow was examined in baroreceptor and chemoreceptor denervated cats. Ouabain was injected into 128 vasoconstrictor or cardioaccelerator sites in the medulla or hypothalamus. Electrical stimulation of 24% of these sites evoked arrhythmias and stimulation consistently caused marked increases in heart rate, blood pressure and nerve activity, but ouabain had several effects, inducing either no change or increases or decreases in spontaneous activity of vasoconstrictor and cardioaccelerator nerves. Effects of ouabain were also observed on signal-averaged potentials evoked in these nerves by electrical stimulation of the medullary or hypothalamic sites of injection. The amplitude of the evoked potentials was either increased, decreased or left unchanged. In general, spontaneous and evoked activities were inhibited by ouabain more frequently than they were enhanced. The pattern of nervous responses to ouabain did not relate to the dose of drug or to the anatomical site of injection. Medullary and hypothalamic injections of ouabain often produced large changes in blood pressure, heart rate and nerve activity, but these effects were not accompanied by alterations in cardiac rhythm. Thus, central microinjections of ouabain produced heterogeneous patterns of effects on activity of peripheral sympathetic nerves, and these microinjections were not sufficient to evoke cardiac arrhythmias in cats with sectioned cranial nerves IX and X.


Critical factors in selecting removable prostheses. Preservation of as many natural teeth as possible should be the goal of conscientious dentists. However, occasionally, the sacrifice of some sound natural teeth may be indicated for partially edentulous patients to provide them with the most functional and esthetic masticatory apparatus. Selection of the proper prosthetic service is one of the most critical value judgments made by dentists. No matter how skillfully the wrong treatment is accomplished, it is still the wrong treatment. It is important, therefore, that all relevant data be gathered so that the best clinical judgment can be brought to bear in the decision-making process.


Minor connector designs for anterior acrylic resin bases: a preliminary study. The effect of nine different designs on the strength of acrylic resin attachment to the partial denture framework in anterior endentulous spaces was tested. Thirty metal frameworks, incorporating nine different designs and a control, were fabricated. Acrylic resin was processed to these frameworks, and the resin was subjected to a shear force. The framework designs offering strong retention for acrylic resin bases allowed the use of a greater bulk of acrylic resin projecting through openings in the metal retention design.


Clinical procedures for improving veneered metal crowns. Satisfactory design and preparation of the veneer window presuppose that a perfect or a near-perfect preparation of the tooth has been made. The window is not just a cutout and is not the responsibility of the laboratory technician. Whenever optimum gingival health, a satisfactory esthetic result, and a long-lasting restoration are desired, it is worthwhile to carefully check and, if necessary, adjust the veneer window directly in the mouth before the veneer is added. This is especially important in restorations that extend below the gingival margin.


An adhesive technique for small anterior fixed partial dentures. A technique for the fabrication of a resin anterior fixed partial denture of intermediate length has been described. This type of device offers an inexpensive, quick treatment for selected patients with two adjacent missing anterior teeth. The technique allows the postponement of a definitive treatment to a more favorable time. The total treatment can be completed in two relatively short appointments.


The provisional fixed partial denture.

The provisional fixed partial denture. A discussion of the rationale and requirements of the provisional restoration in fixed prosthetic dentistry has been presented. The imporatnce of this phase of restorative densitry and a survey of techniques for making interim restorations were gleaned from a review of the literature. A method for the fabrication of a provisional fixed partial denture using an acrylic resin interocclusal record was described and illustrated.


Movement of abutments by removable partial denture frameworks with a hemimaxillectomy obturator. A laboratory experiment was conducted to measure the amount of movement in each of two directions on each of seven teeth, induced by three common designs of retainer, under both splinted and unsplinted conditions. An analysis of variance on a four-way, completely crossed, fixed-effects model showed significant main effects for design, splintedness, and teeth involved. Also of significance were the interactions between the factors of splintedness and teeth and between design and splintedness. Most of the variability in tooth movement was due to differences among the seven teeth (49.3 per cent of variance) and to the interaction of splintedness and teeth (20.2 per cent of variance).


Porcelain occlusal posterior fixed partial dentures. A method for using the functionally generated-path technique to fabricate full occlusal porcelain-fused-to-metal fixed partial dentures and crowns has been described. Proper use of this technique in carefully selected patients should eliminate occlusal adjustments and the concomitant polishing and glazing that are often necessary before the restoration can be permanently cemented.


Articular complications of homotransplantation and chronic renal hemodialysis. Renal homotransplantaion and chronic hemodialysis are accepted methods of treating end-stage kidney disease. However, these procedures are fraught with complications involving bones, joints, and soft tissues. Transplantation and immunosuppressive therapy problems include "connective tissue-like" reactions, infections in joints and avascular necrosis of bone. Long term hemodialysis may accentuate secondary hyperparathyroidism, renal osteodystrophy, and metastatic calcification, which can be minimized by phosphorous control or calcium loading in the dialysate. In the presence of osteomalacia, vitamin D may be helpful and parathyroidectomy is indicated if autonomy is present. In one patient undergoing long term hemodialysis, a chalky material was aspirated from the olecranon bursa. Two inorganic solid phases were identified as being present - a major phase, octacalcium phosphate (ocp) and a minor phase, calcite (CaCO3). Because of its elusive properties, the role of OCP in biological systems is poorly known and can easily escape detection. Methods of identification of OCP and its potential role in crystal deposition syndromes are discussed.


The efficacy of antimalarials in systemic lupus erythematosus. Of 209 patients who fulfilled the A.R.A. criteria for the diagnosis of systemic lupus erythematosus, 43 were selected for study because each had been treated for at least two years with antimalarials, but had not received antimalarials for at least one subsequent year. In each instance, the antimalarial was discontinued solely because of the development of retinopathy. Each year on antimalarials was matched with a subsequent year off antimalarials for each patient. The year immediately following diagnosis and years of pregnancy were excluded. Paired-t test analysis of matched years revealed that general symptoms (fever, fatigue, weight loss) were less common during years on 500 mg chloroquine daily than during years off the drug (p less than 0.05). Skin manifestations were also less frequent during the years on 500 mg chloroquine daily than during the years off (p less than 0.05). No significant steroid sparing effect was found. However, a greater incidence of flare-ups during the matched years off the drug was statistically significant.


Accountability for graduate medical education: report of an unsuccessful experiment. An experiment is reported which utilized a professional medical care organization as the base for intern and resident education. The major reason for its failure was the undue rigidity of Title XVIII (Medicare) of the Social Security Act and associated regulations. The data assembled suggest that the mechanism is feasible and could potentially obviate (or at least minimize) many of the existing problems associated with the operation and financing of graduate medical education using a hospital as the organizational base.


An anatomical, histochemical, and autoradiographic study of the ever-growing molar dentition of Microtus with comments on the role of structure in growth and eruption. An analysis of the microanatomy of the molar dentition of Microtus utilizing histological, histochemical and autoradiographic techniques reveals a complex architecture with distinctive morphogenic mechanisms which respond to the functional requirements of the organism. These mechanisms include; the maintenance of continued growth and eruption of the molars to compensate for continued hard tissue loss from wear at the occlusal surface of the crown throughout the entire lifespan of the orgainism and a positive feedback repair mechanism to protect the growth systems from the potential destruction this normal occlusal wear could initiate. An awareness and understanding of these phenomena is of significant value for interpreting palentological specimens and formulating a theoretical model for interpreting the evolution of Microtine molar dentitions.


Marked histoincompatibility between and within sublines of AKR mice used in a syngeneic leukemia model. Sublines of AKR mice differed significantly in their histoincompatibility to AKR/J mice, as indicated by their ability to reject AKR/J skin grafts and an AKR transplantable leukemia. Further, all sublines tested demonstrated some degree of heterogeneity, because isografts were rejected in 5-97% of the mice, depending on the subline. The presence of excessive heterogeneity among and within sublines poses a serious problem for experimental oncologists using these sublines in their tumor models.


The radioautographic transfer function and its implications for radioautographic methodology. A function was developed to relate the radioautographic detectability of tritiated thymidine to its incorporation into nuclear DNA under various experimental and specimen processing conditions. The implications of this function for the interpretation of cell kinetic studies were outlined, and its implications for radioautographic methodology were discussed. The standardization of radioautographic methods for facilitation of comparisons of data obtained from different sources under dissimilar experimental conditions was discussed.


The discrete phases of the cell cycle: autoradiographic, physical, and chemical evidences. Recently the discrete model of the cell cycle, described as a series of metabolic progressions through four distinct phases, has been challenged by a few curves of percent labeled mitoses (PLM) and related autoradiographic data, which have been questionably interpreted in terms of a "continuous" cell cycle model. This conclusion is based in part on a few questionable observations which we summarize, along with our objections and explanations. We present a critical analysis of the autoradiographic data obtained with the PLM, in terms of the limitations and inconveniences of the technique itself. Some attention is paid to the usefulness of the "radioautographic transfer function," which seems an arbitrary mathematical expression of old autoradiographic observations. Finally, a review is presented of the old (by autoradiography) and new (by physical, chemical, and computer image analysis) evidences of the existence of dicrete phases in the cell cycle, which in turn support the idea of an all-or-none phenomenon for DNA synthesis, and which rule out the hypothesis of a continuous cell cycle model with a varying DNA synthesis rate function.


A microradioimmunoassay for antibodies to tumor-associated antigens. A versatile microradioimmunoassay for the detection of antibodies to tumor-associated and other tissue antigens was described. The method involved: a) the preparation of solid-phase antigen with cultured (already adhered) or noncultured cells (sedimented by centrifugation) fixed to Micro-Test plates with neutral buffered formaldehyde or absolute methanol; b) the incubation of the antigen with test or control sera; and c) the incubation of the antigen with radioiodinated antiglobulin antibody. The nonspecific background of radioactivity was reduced to an acceptable level by the fixed cells being precoated in the wells with 0.5% bovine serum albumin in phosphate-buffered saline which was also used for the dilution of sera and labeled antiglobulin antibody. Tumor cells in primary cultures gave a high background, as compared to long-term cultures, which was due to the presence of immunoglobulins (most likely tumor-specific antibody). The specific antibody response to a syngeneic mouse tumor was demonstrated by this technique.


Bladder neck contracture and urethral stricture as complications of renal transplantation. From 1963 to July 26, 1974, 211 men underwent renal transplantation at our clinic. Urethral strictures were present prior to the initial transplant in 4 patients (1.8 per cent) and developed in the post-transplant period in 13 patients (6.1 per cent). Postoperative bladder neck contractures occurred in 2 patients (0.9 per cent). Repeated urethral dilations and surgical procedures on the lower urinary tract were generally well tolerated. Infectious problems were the most common secondary complications. No patient or allograft was lost as a direct result of the lower tract obstruction or its treatment. The greatest morbidity occurred in those patients who had a combination of urethral stricture and/or bladder neck contracture, uremia, previous or current immunosuppression and the absence of urine flowing through the urinary tract. This combination occurred most often in the patient who experienced failure of the first allograft and was being prepared for a second or third transplant. To avoid potentially serious urologic complications, male patients should have a repeat lower urinary tract evaluation and definitive correction of existing obstruction before re-transplantation is considered.


Lymphocyst: ultrasound diagnosis and urologic management. Three cases of lymphocysts occurred in a series of 97 patients undergoing extension pelvic urological operations, an incidence rate of 3.1 per cent. This is the first report of this complication after urological lymphadenectomy. Awareness of the entity is important to urologists since lymphatic staging operations for prostate and bladder carcinoma are widely used to help plan definitive therapy. Athough this complication is rare after renal transplantation it may cause significant interference with graft function. The etiology, symptoms, findings, diagnosis and treatment of this condition are reviewed. Echography is presented as an ideal technique to diagnose the condition and to guide in its management.


Rapid miniaturized tests for bacteriuria: Microstix and bacturcult urine tests. Of 4 methods for testing random urine samples for the presence of infection the standard hospital laboratory culture-colony counting was found by far to be the most accurate. Microscopy of urinary sediment, Microstix and Bacturcult produced too many falsely negative results to be useful in a clinical setting, were urine samples were collected throughout the day such as in an office or hospital outpatient clinic. Perhaps the last 2 tests would yield better results if urine samples were collected after at least 4 hours of incubation time in the bladder, as suggested by their proponents.


Recurrence of the nephrotic syndrome in the renal isograft: A preliminary report. The fifth case of kidney transplantation between monozygotic twins in Japan is presented. Immediately after the transplanation the original disease, nephrotic syndrome, recurred but it was treated with steroids successfully. There have been few cases reported in which recurrence of the original disease in the isograft was treated successfully.


Cerebral blood volume in man. Computer analysis of a computerized brain scan. Cerebral blood volume in man can be measured by subtracting computerized axial tomogram density measurements taken before from those taken after an intravascular marker is infused into the blood. The average blood volume is 3.0 ml/100 ml of brain tissue, with a range of 2.4 to 4.25. This method can be applied in studying cerebral pathologic conditions. Areas of cerebral edema, surrounding a tumor, have a decreased blood volume.


Hemoglobinopathy with prolonged bactermia. A report of two cases. Prolonged Escherichia coli bacteremia occurred as a complication of pyelonephritis in two patients with abnormal hemoglobins (SC and SS), despite "appropriate" antibiotic therapy. Careful investigation in each case failed to account for the persistent sepsis. Pyogenic arthritis ultimately developed in both patients.


Listeria sepsis and meningitis: A complication of renal transplantation. Listeria infections is an important cause of sepsis and meningitis in renal transplant patients. Prompt recognition and aggressive therapy are required to control this life-threatening infection. In 1972, one case of listeriosis occurred in a renal transplant recipient in our center; 1974, six more cases were detected within a period of nine months. All seven patients had Listeria sepsis, and three of the seven patients had both sepsis and meningitis. Antibiotic treatment resulted in remarkable improvement in the clinical state of all the patients in this study. Two patients later died of other unrelated causes.


Disseminated aspergillosis in a renal transplant patient: Diagnostic difficulties re-emphasized. An asymptomatic and radiographically occult lung abscess was the primary focus of infection in this case of fatal disseminated aspergillosis in a renal transplant recipient. Extensive neurological evaluation in response to a change in personality failed to reveal a brain abscess, which was the cause of death. This case illustrates the variability in presentations of aspergillosis and the continuing difficulties in diagnosing this infection in immunosuppressed patients.


[Methods of calculation of functional volumes of the heart ventricle]. The method of thermodilution permitted a broader investigation of the methods of calculations of the functional heart volumes. Two methods (Holt and Luthy) were compared with one another and with the control. Both methods were used for calculating the end-diastolic volume (Qed). Studies in the calorimeter and on a model with a pulsating flow demonstrated that the first portion of the thermodilution curve is a function of the myocardial contractility. Both the Holt and Luthy methods give equally reliable results, but the Holt technique is preferable for Qed measurements.


[Simplified method of radiocardiographic study of central hemodynamics]. The possibility of calculating the main parameters of the cardiac output and the pulmonary blood flow on the basis of a radiocardiogram alone, without performing radiometry of the administered dose of the isotope, and determination of the venous blood activity, is discussed. It is offered to use the relative indices of hemodynamics for this purpose: the indices expressing the values of the minute and stroke volumes, the circulating blood volume in the lungs expressed as percentage of the total circulating blood volume. A high degree of correlation between the absolute and relative indices of the central hemodynamics was established, the advantages and disadvantages of the simplied method of radiocardiography are revealed. The rationale of a parallel determination of the absolute and relative values of the hemodynamic parameters is emphasized since it permits a deeper insight into the hemodynamic shifts.


[Selection of a rational method of calculation of minute blood volume by the dye dilution curves]. In calculating the cardiac output on the basis of the dye dilution curves it is important to determine the area of the first circulation of the dye. The existing techniques of the determination of this area are different in their complexity and precision of the obtained results. A comparative evaluation of 14 techniques or their modifications for the determination of the cardiac output according to the Evans blue dilution curves was undertaken in 40 subjects (normal individuals and patients with chronic pulmonary pathology). A new method of calculations of the area by two triangles is suggested. The most precise techniques appeared to be the planimetric method of exponential extrapolation, the two and five triangles methods introduced by the authors, as well as the calculations of Hamilton and Simpson. It seems most rational to use the two and five triangles methods that are not only precise, but also simple. The method with five rectangular triangles should be preferred since it does not require any special equipment. In exceptional cases, in which the recirculation wave begins early and/or the direction of the descending portion is not clear, the Dow equation may be recommended, with the results multiplied by the factor of 1.26.


[Symptomatology, differential diagnosis and treatment of bacterial meningitis of newborns and infants (author's transl)]. Bacterial meningitis in our hospital too shows its maximal frequence with 30.5% in the first month of life, 25.2% of these cases being newborns. The frequent difficulties of diagnosis in this period of life are demonstrated. Predisposing factors and possible complications of meningitis are named. The principles of modern therapy are summarized.


Immunohistochemical evidence for the presence of collagen type III in human arterial walls, arterial thrombi, and in leukocytes, incubated with collagen in vitro. Sections of arterial walls and of thrombi and smears of leukocytes previously incubated in vitro with collagen type III were examined by immunohistochemical technique for the presence of collagen types I, II and III. In arterial walls collagen type III was detected immediately underlaying the endothelial cell layer and in the tissue between tunica elastica interna and adventitia. Collagen type I was not shown in the subendothelial layer. Fresh thrombi contained occasionally collagen, but only of type III. This was associated with leukocytes. Leukocytes were capable in vitro to associate and/or phagocytose collagen type III and this could be visualized immunohistochemically. The data show that collagen type III in vivo may play a crucial role in the initiation of thrombus formation.


Pancreatic beta cell changes induced by cyproheptadine in vitro. The effect of cyproheptadine on the structure and function of rat pancreatic beta cells was studied in vitro by culturing isolated islets in media containing the drug (0.5 mM). After 8 days in culture the ultrastructure of islet cells maintained in control media appeared well preserved, being similar to the previously reported for islets kept in long term organ culture. In contrast beta cells from islets incubated in media containing cyproheptadine appeared degranulated and the rough endoplasmic reticulum showed cisternal dilation and vacuole formation. These vacuoles were filled with an electron-dense granular material and their surface was usually studded with ribosomes. These lesions are identical with those produced by the administration of cyproheptadine to rats in vivo. In addition to these findings, increased numbers of lysosomes and myeloid bodies were observed in both alpha and beta cells. Compared with that of the controls, the 24-hour basal insulin secretion of islets cultured in the presence of cyproheptadine was significantly reduced from the 4th day of the study onwards. It is thus concluded that cyproheptadine has direct effects on the morphology and function of the rat pancreatic beta cell.


Age dependence of viral expression. Electron microscopic and immunoperoxidase studies of Measles virus replication in mice. The hamster neurotropic strain of measles virus inoculated intracerebrally into BALB/c mice causes a uniformly fatal encephalitis with production of infectious virus in 1- to 2-day-old suckling mice but a 31 per cent mortality with production of measles virus antigen without production of infectious virus in 4-week-weanling mice (8). These two groups of animals were studied using routine electron microscopy and the immunoperoxidase technique in order to determine the nature of the measles virus antigen produced in each situation. Suckling animals showed numerous cytoplasmic viral inclusions in neurons and glia. This nucleocapsid material stained specifically with rabbit antiserum to measles virus antigen overlayed with peroxidase-conjugated goat antirabbit gamma-globulin. Histologic and electron microscopic study of weanling mice revealed rare necrotic cells and occasional loose clusters of neurons with depolymerized ribosomes. Immunoperoxidase staining showed diffuse cytoplasmic staining of similar groups of neurons and dendritic processes without evidence of nucleocapsid material. These differences in virus replication appear to be a function of the maturation of the host cell rather than the measles virus. Hamster neurotropic virus infection of the weanling mouse is an example of a potentially fatal virus infection in which viral replication is defective at a stage prior to assembly of nucleocapsid material; thus, no direct morphologic evidence that the cause of the clinical disease is a viral infection is present.


Cinemicrographic studies on beta granule movement in monolayer culture of islet cells. Monolayer cultures of adult rat islets were used for cinemicrographic studies on the movement of beta granules in the cytoplasm of beta cells. Stimulation of insulin release by glucose produced a significant increase in the amount of beta granule movement in the cultured cells. Disruption of the microtubular system with vinblastine or stabilization of microtubules with deuterium oxide inhibited the induction of granule movement by glucose. Incubation of the cultures in the absence of calcium inhibited glucose-induced movement of beta granules, whereas the subsequent addition of calcium permitted movement to occur. The addition of epinephrine also inhibited glucose-induced beta granule movement. In the presence of nonstimulating levels of glucose, movement of beta granules was present. The amount of movement varied from cell to cell suggesting a difference in base line activity of individual beta cells. The movement of individual beta granules was saltatory in type, and the average rate of movement was 1.5 mum. per second. The study demonstrated that directed movement of beta granules occurs following stimulation with glucose and adds further support to the hypothesis that the microtubular-microfilamentous system is involved in the intracellular translocation of beta granules to the cell surface where they are released by emiocytosis.


The relationship between discrimination and articulation training in children with misarticulations. In the context of a training study, the functional relationship between discrimination and production was investigated. Four subjects were selected for study. For two subjects, Condition I consisted of production training followed by a discrimination probe and Condition II consisted of discrimination training followed by a production probe. For the other two subjects, the conditions were reversed. In production training, the subjects were trained to correctly articulate three consonant-vowel (CV) syllables in response to nonsense pictures. In discrimination training the subjects were trained to find nonsense pictures in response to three CV syllables. Probe measures were administered to determine if changes occurred in one modality after training the other modality. Results indicated that production training was effective in changing both articulation and discrimination; however, discrimination training was effective in changing only discrimination.