Opsonization of normal myelin by anti-myelin antibodies and normal serum.

Fc receptor-dependent myelin phagocytosis has been proposed as a possible important effector mechanism in several immune-mediated demyelinating diseases. The present study was designed to determine whether myelin is opsonizable by anti-myelin antibodies. Thioglycolate-elicited mouse peritoneal macrophages were cultured with 125I-labelled bovine central myelin pretreated with normal or immune serum. Serum opsonic activity was determined by a kinetic study comparing macrophage uptake of opsonized and untreated 125I-myelin. Heat-stable and heat-labile myelin opsonins were detected in normal rabbit serum. Myelin was also opsonized by normal rabbit gamma globulin and by heat-inactivated normal mouse, human, and guinea pig serum. Increased opsonic activity was detected in rabbit anti-myelin antiserum and the gamma globulin fraction prepared from this serum, in anti-myelin basic protein and anti-galactocerebroside antiserum but not in anti-myelin-associated glycoprotein antiserum or in serum from rabbits injected with Freund's adjuvant alone. One out of three anti-sheep red blood cell antisera tested also showed increased myelin opsonic activity. It is concluded that anti-myelin antibodies can promote opsonic phagocytosis, and that normal serum and normal serum gamma globulin also opsonize myelin.

Sera from MS patients and normal controls opsonize myelin.

Fc receptor-dependent myelin phagocytosis has been proposed as a mechanism of demyelination in multiple sclerosis (MS). The object of this study was to determine whether MS patients' sera are more opsonic for myelin than normal controls' sera. Opsonization was tested by culturing thioglycollate elicited murine peritoneal macrophages with 125I-labelled, serum-sensitized bovine central myelin. The two groups of sera were found to opsonize myelin equally well after 30 and 120 min incubations. We conclude that MS patients' sera are not more opsonic for myelin than sera from normal controls.

[Cesarean sections: an epidemic profile]. / Cesáreas: um perfil epidêmico.

This study characterizes cesarean rates among women giving birth in São José do Rio Preto in 1992. Household interviews were conducted with 553 women selected through records on live births. Estimated incidence of cesarean sections was 80.5%, highlighting the procedure's widespread use in the study sample. Confirming a prior hypothesis, cesarean rates increased with parity and were statistically associated with age and tubal ligation. As for socioeconomic status, cesarean rates increased according to income and were higher among women using private health care (with or without health insurance). Interviews with professors in the local medical school and a related survey of the local media showed an increase in the valorization of cesareans. Confirming this trend, women interviewed in the survey expressed their own active valorization of this procedure.

[Diabetes as primary or associated cause of death in the state of São Paulo, Brazil, 1992]. / Diabetes como causa básica ou associada de morte no estado de São Paulo, Brazil, 1992.

INTRODUCTION: Analysis of mortality data are usually performed with reference to the underlying cause of death. The importance of diabetes as a cause of death is always underestimated, because diabetics generally die from chronic complications of the disease, these being considered as the underlying cause of the death. To attenuate this problem, mortality data should be analyzed on the basis of all the causes listed on the death certificate. Frequency of references to diabetes on death certificates and the principal associated causes were evaluated as a contribution to the solution of this problem. METHODOLOGY: Specific death rates and proportional mortality by diabetes, as underlying or associated cause, were calculated on the basis of information derived from death certificates by the ACME program (Automated Classification of Medical Entities), for the State of S. Paulo, in 1992. RESULTS AND CONCLUSIONS: Of a total of 202,141 deaths, diabetes was mentioned in 13,786 (6.8%) and as being the underlying cause in 5,305(2.6%). The proportion was higher for women than men (10.1 vs. 4.6% as mentioned, and 6.1 vs 2.9% as underlying cause). Among deaths with a mention of diabetes on the certificate, the main underlying causes were: diabetes (38.5%), cardiovascular (37.2%) and respiratory (8.5%) diseases, and neoplasias (4.8%). When diabetes was the underlying cause, the main associated causes were: cardiovascular (42.2%), respiratory (10.7%) and genitourinary (10.1%) diseases. When diabetes was an associated cause, the main underlying causes were: cardiovascular (60.5%) and respiratory (13.8%) diseases, and neoplasias (7.9%). In spite of the limitation of the data from death certificates, it is possible to observe the importance of diabetes as cause of death, reflecting its magnitude as a health problem. Also, the analysis by multiple causes of deaths gives an idea of the morbidity profile associated with diabetes at the time of death, showing the importance of the group of cardiovascular diseases.

[Medical graduation and specialization: an apparent incompatibility]. / Graduação médica e especialização: uma incompatibilidade aparente.

PURPOSE: Partial results of a continuous evaluation process of the undergraduate medical course at Escola Paulista de Medicina (EPM) started in 1989 are presented. METHODS: A survey on expectations and opinions about the medical course of EPM was carried out among faculty members, students and alumni. RESULTS: The authors call into question that the medical formation is non-terminal as indicated by the late entry to labor market. CONCLUSION: The authors consider that the phenomenon is not related to quality aspects but to the specialization process started during the medical course and completed only with graduated studies.

Evidence for an H-Y crossreactive antigen in invertebrates.

A sex specific antigen which crossreacts with the mammalian H-Y antigen has been identified on the cell surface of hemocytes from the lobster (Homarus americanus) and the gonadal cells of three insect species. The hemocytes from the male lobster, the testicular cells from the male beetle (P. cornutus), and the ovarian cells from two Orthopteran species (L. maderae and D. punctata) specifically absorbed H-Y antibodies. The specificity of H-Y antibody absorptions by cells from only one sex, suggest that an ancestral H-Y-like antigen may be present in invertebrates which could be engaged in sexual (cellular) recognition events.

Interaction of astrocytes and newly formed oligodendrocytes in resolving multiple sclerosis lesions.

Cells resembling oligodendrocytes are sometimes seen within reactive astrocytes in fresh lesions in multiple sclerosis. Using immunostained paraffin and epoxy sections of fresh plaques obtained at autopsy from a series of cases of short clinical duration, it was found that small cells with round nuclei are commonly observed within reactive astrocytes in some hypercellular plaques and that these cells are phenotypically undifferentiated oligodendrocytes, i.e., nonmyelinating cells expressing intensely the oligodendrocyte determinants 2',3'-cyclic nucleotide 3'-phosphohydrolase and the carbohydrate epitope present on the family of cell adhesion molecules recognized by monoclonal antibody HNK-1. They also stain positively for IgG. This unusual astrocyte-oligodendrocyte interaction, which appears to be restricted to nonmyelinating oligodendrocytes in lesions of several weeks' to several months' duration, has not been described during normal oligodendrocyte differentiation or in experimental central remyelinating lesions. It bears some resemblance, however, to a pattern of slow oligodendrocyte destruction seen previously in organotypic perinatal central nervous tissue cultures exposed to multiple sclerosis serum. It is concluded that the evolution of some multiple sclerosis lesions early in the course of the disease is associated with abnormal binding and/or destruction of newly generated oligodendrocytes by reactive astrocytes. These observations raise new questions concerning mechanisms underlying failed remyelination in multiple sclerosis, including the novel possibility of an immune response directed against a developmentally restricted oligodendrocyte antigen.

Remarkable improvement in adult Leigh syndrome with partial cytochrome c oxidase deficiency.

Leigh syndrome (LS) is a heterogeneous disorder, usually due to a defect in oxidative metabolism. Typically, signs and symptoms commence in infancy or childhood, although rare cases of adult onset have been described. Progressive deterioration is the norm. The authors describe a 22-year-old woman with partial cytochrome c oxidase deficiency who developed fulminant LS following an acute febrile illness and who subsequently showed dramatic clinical and neuroradiologic improvement.

Multiple sclerosis. Oligodendrocyte proliferation and differentiation in fresh lesions.

Fresh lesions in the brain and spinal cord of patients with multiple sclerosis who died shortly after the onset of symptoms were examined immunocytochemically for myelin and oligodendrocyte antigens that are known to be sequentially expressed during normal development. Cells with oligodendrocyte-like morphology that appear in large numbers throughout fresh lesions after acute myelin breakdown and before new myelin formation were found to express galactocerebroside, carbonic anhydrase, and 2',3'-cyclic nucleotide 3'-phosphohydrolase but not myelin-associated glycoprotein or myelin basic protein. They also exhibit intense surface reactivity for a carbohydrate epitope associated with the family of cell adhesion molecules recognized by the monoclonal antibody HNK-1. With the onset of remyelination and the appearance of myelin-associated glycoprotein, myelin basic proteins, CNP, and the HNK-1 epitope is newly formed myelin sheaths, perikaryon CNP and HNK-1 reactivity diminished. A possible oligodendrocyte precursor cell in the form of a large HNK-1 positive glial fibrillary acidic protein negative glial cell was observed among interfascicular oligodendrocytes in white matter bordering these hypercellular plaques. Because a similar progression in the expression of CNP and the HNK-1 epitope occurs during normal oligodendrocyte differentiation, these observations are additional evidence that extensive oligodendrocyte regeneration occurs in some plaques early in the course of the disease. The finding of large numbers of immature oligodendrocytes, presumably expressing many developmentally restricted antigens not normally present in the mature nervous system, in plaques at a particular stage in their evolution may be important in understanding why remyelination eventually fails in multiple sclerosis.

[Self-reported diabetes mellitus in the city of São Paulo: prevalence and inequality] / Diabetes mellitus auto-referido no Município de São Paulo: prevalência e desigualdade.

This report analyzes characteristics of self-reported diabetes mellitus in the city of São Paulo, Brazil. The data were obtained from the Brazilian Multicenter Study on Prevalence of Diabetes Mellitus, a household survey performed in 1986-88. The São Paulo sample consisted of 2,007 individuals aged 30-69 years, of both sexes, selected from three areas with distinct socio-economic levels. The estimated prevalence using a 75g glucose load and measurement of two-hour capillary glycemia was 9.7%. Prevalence of self-reported diabetes was 4.7% and increased with age and presence of family history of diabetes. There was a significant difference between sexes (3.5% in men and 5.7% in women), with higher rates of self-reported diabetes at higher economic levels among men and higher rates at lower socio-economic levels among women.

A dimensao social das doencas. II - Positividade das reacoes de Wasserman e VDRL em convocados para o servico militar no Estado de Sao Paulo (Brasil), de 1972 a 1978. / The social dimension of diseases. II - Positivity of Wasserman and VDRL reactions in draftees of the State of Sao Paulo (Brazil)

Em sequencia a serie historica iniciada em 1968, com o objetivo de obter indicacoes sobre a evolucao da sifilis no Estado de Sao Paulo (Brasil), foi feito levantamento dos dados de 1972 a 1978 que mostrou que ao longo do tempo e apesar das oscilacoes, nao houve variacoes substanciais dos coeficientes de positividade das reacoes de Wasserman e VDRL em convocados apresentados no municipio de Sao Paulo. No interior do Estado o aumento dos valores dos coeficientes de 1973, invertendo a tendencia anteriormente observada, aproxima esses indices aos do municipio. O estudo da subamostra indicou a presenca de proporcoes maiores de positividade em convocados apresentados no municipio comparados com os apresentados no interior do Estado,independentes da naturalidade, o que poderia sugerir semelhancas com os quadros epidemiologicos descritos para os paises desenvolvidos. Entre convocados apresentados na capital observou-se maiores proporcoes de positividade nos convocados nascidos em outros Estados do pais, o que evidenciaria a presenca da doenca associada a pobreza ou ao subdesenvolvimento. Nesse sentido, foi chamada a atencao para as peculiaridades epidemiologicas das doencas em vista da singularidade das respectivas organizacoes sociais num dado momento historico