An endogenous modulator of N-methyl-D-aspartate receptor-coupled glycine receptors

Extensive washing of a membrane preparation from rat brain resulted in a progressive enhancement of strychnine-insensitive [3H]glycine binding, which was due to an increase in the number of binding sites with no changes in the apparent affinity of this radioligand, precluding an explanation based solely on the elimination of endogenous glycine. Moreover, after extensive washing a population of [3H]glycine binding sites with very high affinity for L-serine was observed in addition to the sites with low affinity for L-serine present in less extensively washed tissue. The observed changes in [3H]glycine binding were attributable to the elimination of a low molecular weight, heat-stable compound which was readily detected in the wash supernatant. Extensive washing also altered [3H](+)-5-methyl-10,11-dihydro-5H-dibenzo-[a,d]cyclohept-5,10-i min e maleate ([3H]MK-801) binding to N-methyl-D-aspartate (NMDA) receptor-associated channels, decreasing basal binding at equilibrium and producing slower association rates in the presence of either glycine or L-glutamate. Moreover, in well-washed membranes both glycine and glutamate enhanced [3H]MK-801 binding acting at high- and low-affinity sites. These findings suggest that the NMDA receptor complex can assume interconverting conformational states regulated by an endogenous substance(s).     

Experimental models of hypersensitivity pneumonitis.

Experimental models of hypersensitivity pneumonitis are important tools for the study of the pathogenesis of this disease. In this paper we review the characteristics of the main animal models developed until now. The HP models in rats seem to be particularly appropriate for studying pigeon fancier's disease and the HP induced by chemicals, as well as for studying mediators of acute lesions induced by immunocomplexes. However, the HP models developed in rats are of less value in the evaluation of other aspects of the pathogenesis of this clinical entity in humans. The murine models of HP offer several advantages: the ease and simplicity of intranasal administration, the ability to produce acute and subacute pulmonary lesions similar to those found in humans, the possibility of reproducing lesions similar to those of nonaffected exposed subjects and the possibility of pharmacologically modulating the process. Their disadvantages lie in the different pulmonary lymphocyte response and the difficulty in reproducing a model of chronic fibrosis. The HP models in rabbits are extraordinarily useful for evaluating the immunological mechanisms through which subjects repeatedly exposed to the antigen do not develop clinical manifestations. However, the rabbit has several immunological differences when compared to humans, and the effect of some immunomodulators in this animal is different. The models of HP in guinea-pigs have as advantages the ease in handling the animals, the possibility of pharmacological manipulation, and the ability to induce an acute phase that is very similar to that observed in humans. The drawback, however, is the low lymphocyte response and the striking eosinophilic reaction that contrast with the bronchoalveolar data found in HP in humans. In conclusion, there is no ideal model to reproduce all the findings observed in humans, suggesting that the experimental animal and the method of developing HP should be selected on the basis of concrete research aims.     

A new marker of epidermal differentiation associated with the membrane coating granules: characterization and applications to pathology.

A murine monoclonal antibody, BC12, was obtained after immunization against suprabasal human keratinocytes. In the epidermis of normal human skin, the antigen recognized by BC12 (BC12 antigen) is located at the apex of keratinocytes in the upper stratum spinosum and stratum granulosum but is absent in other layers. The BC12 antigen is also present in hair follicles. Immunoblotting performed on keratinocyte subpopulations confirmed the presence of the BC12 antigen in differentiated keratinocytes only. Two-dimensional immunoblotting showed that the BC12 antigen corresponds to a set of polypeptides with an apparent molecular weight of approximately 33kD. In keratinocyte cultures, the antigen is present only in stratified areas. The distribution of the BC12 antigen, as studied by indirect immunofluorescence and immunoelectron microscopy, and its presence in certain subcellular fractions of epidermal cells suggest that it is a component of membrane coating granules (MCGs) or that it is associated with these structures. Strikingly, in psoriasis, eczema and many other diseases, the BC12 antibody does not label the epidermis, but vessels in dermal papillae. The BC12 antibody may thus be a useful tool in the study of keratinocyte differentiation and MCG physiology, and, also, in pathology.     

Characteristics of women performing strength training: comparison of participants and dropouts.

The physiological, anthropometric, personality and lifestyle characteristics of 122 women volunteering for a seven-week program of heavy resistance weight training were studied relative to adherence rates. Initially, volunteers were above-average in body mass and grip strength, but were below-average in chest girth and bicristal diameter. They were also physically active and only 20% smoked. Regular (R) attenders (attendance greater than 80%; 72% of the sample) were physically smaller in terms of stature, mass, girths and dimensions, but had greater strength per kg of mass or LBM compared to participants classified as infrequent (I; 24-76%) and dropout (DO; less than 20%). Conversely, I and DO members were more likely to smoke, to smoke more heavily, to drink coffee and to not eat breakfast. Most dropouts quit during the first week; among volunteers who continued, differences in assigned training intensity had no effect on adherence. Adherence was also unrelated to strength gains, anthropometric adaptations, or injury.     

Profiles of alcoholics according to the SCL-90-R: a confirmative study.

The Symptom Checklist-90-Revised (SCL-90-R) has often been used in studies of alcoholic populations. Based on findings reported in the literature and data gathered on 712 alcoholics in treatment, this paper investigates the general trends in the responses of alcoholics to the SCL-90-R. On global measures as well as on each of the symptom scales, the scores of alcoholic groups reveal a symptomatology two to five times as severe as that observed in the general population. The Psychoticism dimension shows the most marked divergence with the general population. In almost each of the study groups, the Depression Scale registers the highest scores, followed by Obsessive-Compulsive, Interpersonal Sensitivity, and Anxiety.     

A foodborne outbreak of group A streptococcal disease at a birthday party.

A severe foodborne outbreak of group A streptococcal disease (T28) affected 122/169 people (72%) who attended a church party or ate leftovers from the party. The median incubation time was 42 h. Muscular pain or weakness and fatigue usually preceded pharyngeal symptoms. Complications included otitis media with perforation, peritonsillitis requiring tonsillectomy, arthritis and pericarditis. A 45-year-old man died 36 h after he developed an influenza-like illness, and at necropsy there were histological signs of early streptococcal septicaemia. The strain produced erythrogenic exotoxins B and C. Streptococci were probably transmitted by sliced eggs on sandwiches. Laboratory experiments showed that there was an increment in viable count of streptococci with 6 logs after incubation in egg yolk for 24 h at room temperature. The unusually warm climate and flaws in food handling routines contributed to this large foodborne epidemic.     

First radiological description of Morgagni's hydatid. Laparoscopic confirmation

The authors explain the clinical case of a female patient suffering from secondary sterility; she was submitted, among other test, to the H.S.G. in order to study the possibility of a among other tests, to the H.S.G. in order to study the possibility of a cervical failure. The radiological findings obtained of Morgagni's Hydatis, not described previously in literature and their laparoscopic confirmation justify, we believe, its publication.     

Albendazole therapy for giant subarachnoid cysticerci.

Albendazole is considered to be the drug of choice for treatment of parenchymal brain cysticercosis. Its efficacy, however, for treatment of subarachnoid cysticerci has not been established, to our knowledge. In this study, we treated four patients who had giant subarachnoid cysticerci with albendazole at daily doses of 15 mg/kg of body weight for 8 days. Computed tomographic studies showed that all cysts disappeared 3 months after the end of treatment. This was associated with marked clinical improvement in every case. Our results indicated that albendazole is highly effective for treatment of this form of the disease.