Perfil cardiovascular após a inoculação intravenosa de veneno de abelha africanizada em ratos acordados

The manifestations caused by Africanized bee stings depend on the sensitivity of the victim and the toxicity of the venom. Previous studies in our laboratory have demonstrated cardiac changes and acute tubular necrosis (ATN) in the kidney of rats inoculated with Africanized bee venom (ABV). The aim of the present study was to evaluate the changes in mean arterial pressure (MAP) and heart rate (HR) over a period of 24 h after intravenous injection of ABV in awake rats. A significant reduction in basal HR as well as in basal MAP occurred immediately after ABV injection in the experimental animals. HR was back to basal level 2 min after ABV injection and remained normal during the time course of the experiment, while MAP returned to basal level 10 min later and remained at this level for the next 5 h. However, MAP presented again a significant reduction by the 7th and 8th h and returned to the basal level by the 24th h. The fall in MAP may contribute to the pathogenesis of ATN observed. The fall in MAP probably is due to several factors, in addition to the cardiac changes already demonstrated, it is possible that the components of the venom themselves or even substances released in the organism play some role in vascular beds.As manifestações causadas por picadas de abelhas africanizadas dependem da sensibilidade da vítima e da toxicidade do veneno. Estudos anteriores em nosso laboratório mostraram alterações cardíacas e necrose tubular aguda (NTA) nos rins de ratos inoculados com veneno de abelhas africanizadas (VAA). O objetivo do presente estudo foi avaliar as alterações na pressão arterial média (PAM) e na freqüência cardíaca (FC) num período de 24 horas após a inoculação de VAA em ratos mantidos acordados. Uma redução significante na FC basal e na PAM ocorreu imediatamente após a inoculação de VAA nos animais experimentais. A FC voltou aos níveis basais 2 min após a inoculação do VAA e permaneceu nestes valores durante o restante do experimento, enquanto que a PAM voltou aos níveis basais 10 min após a inoculação e permaneceu nestes níveis pelas próximas 5 horas. Por outro lado, a PAM apresentou uma nova diminuição significante nas 7ª e 8ª horas retornando aos níveis basais na 24ª hora. A queda na PAM nos animais inoculados com VAA deve contribuir na patogênese da NTA observada nos rins destes animais. Provavelmente a queda da PAM seja multifatorial, além das alterações cardíacas já demonstradas, os próprios componentes do veneno e/ou substâncias liberadas no organismo podem atuar na resistência vascular, contribuindo para alterações na pressão arterial

Avaliação morfológica e morfométrica das ilhotas pancreáticas na fase crônica da doença de Chagas

PURPOSE: Hyperglycemia and abnormal glucose tolerance tests observed in some patients with chronic Chagas' disease suggest the possibility of morphological changes in pancreatic islets and/or denervation. The purpose of this study was to describe the morphology and morphometry of pancreatic islets in chronic Chagas' disease. METHODS: Morphologic and computerized morphometric studies were performed in fragments of the head, body, and tail regions of the pancreas obtained at necropsies of 8 normal controls and 17 patients with chronic Chagas' disease: 8 with the digestive form (Megas) and 9 with the congestive heart failure form. RESULTS: The Megas group had a larger (p < 0.05) pancreatic islet area in the tail of the pancreas (10649.3 ± 4408.8 µm²) than the normal control (9481.8 ± 3242.4 µm²) and congestive heart failure (9475.1 ± 2104.9 µm²) groups; likewise, the density of the pancreatic islets (PI) was greater (1.2 ± 0.7 vs. 0.9 ± 0.6 vs. 1.9 ± 1.0 PI/mm², respectively). In the tail region of the pancreas of patients with the Megas form, there was a significant and positive correlation (r = +0.73) between the area and density of pancreatic islets. Discrete fibrosis and leukocytic infiltrates were found in pancreatic ganglia and pancreatic islets of the patients with Chagas' disease. Trypanosoma cruzi nests were not observed in the examined sections. Individuals with the Megas form of Chagas' disease showed increased area and density of pancreatic islets in the tail of the pancreas. CONCLUSION: The observed morphometric and morphologic alterations are consistent with functional changes in the pancreas, including glycemia and insulin disturbances.OBJETIVO: Hiperglicemia e anormalidades em testes de tolerância à glicose, observadas em alguns pacientes chagásicos crônicos, sugerem um possível papel de alterações morfológicas e desnervação de ilhotas pancreáticas (IP). Nosso objetivo foi descrever a morfologia e a morfometria de ilhotas pancreáticas na doença de Chagas crônica. MÉTODOS: Estudo morfológico e morfometria computadorizada foram realizados em fragmentos da cabeça, corpo e cauda de pâncreas obtidos em necropsias de oito controles normais e dezessete pacientes chagásicos crônicos; oito com a forma digestiva (Megas) e nove com o quadro clínico de insuficiência cardíaca congestiva. RESULTADOS: O grupo Megas mostrou ilhotas pancreáticas de maior (p < 0,05) área na cauda do pâncreas (10.649,3 ± 4.408,8 µm²) do que os controles normais (9.481,8 ± 3.242,4 µm²) e que o grupo com insuficiência cardíaca congestiva (9.475,1 ± 2.104,9 µm²); o mesmo ocorrendo com a densidade das ilhotas na cauda do pâncreas (respectivamente, 1,2 ± 0,7 vs. 0,9 ± 0,6 vs. 1,9 ± 1,0 IP/mm²). Na cauda do pâncreas dos casos com Megas, houve correlação positiva e significante (r = + 0,73) entre a área e a densidade das ilhotas pancreáticas. Discreta fibrose e infiltrados leucocitários foram vistos nas ilhotas e em gânglios pancreáticos dos pacientes chagásicos. Ninhos de Trypanosoma cruzi não foram observados nos cortes examinados. Indivíduos com a forma Megas da doença de Chagas mostraram aumento da área e da densidade das ilhotas na cauda do pâncreas. CONCLUSÃO: As alterações morfológicas e morfométricas observadas são consistentes com alterações funcionais do pâncreas, incluindo distúrbios da glicemia e da insulinemia

Avaliação morfológica da membrana basal das cordas vocais de adultos autopsiados e sua correlação com as causas de óbito

PURPOSE: The purpose of this study was to identify the possible alteration in the thickness of the epithelium basal membrane of the vocal cords and correlate it with the cause of death. METHOD: Larynxes collected from adult autopsies during the period of 1993 to 2001 were utilized. We used the hematoxylin-eosin and periodic acid-Schiff staining methods for the morphological and morphometric analysis. RESULTS: Sixty-six vocal cords were analysed; increased thickness was identified in 14 cases (21.2%), with equal proportions between the genders. Increased vocal-cord thickness was more frequent in patients of the white ethnicity (12 cases, 85.7%). Respiratory alterations were found in 10 (71.4%) of the cases with increased vocal-cord thickness. Of the patients that were maintained with mechanical ventilation before death, 7 (18.4%) had thickening of the basal membrane. Among the smokers, 9 (19.63%) had basal membrane thickening. CONCLUSION: No statistically significant differences were found between the cases in which the cause of death was related to respiratory diseases as compared to non-respiratory diseases and the thickening of the basal membrane of the vocal cords. However, new studies are needed in order to verify the etiopathogenesis of this thickening.OBJETIVO: O objetivo deste trabalho foi identificar as possíveis alterações na espessura da membrana basal das cordas vocais e relacionar estas com a causa de morte. MÉTODO: Foram utilizadas laringes coletadas de adultos autopsiados, no período de 1993 até 2001. Realizamos as colorações da Hematoxilina- Eosina e Ácido Periódico de Schiff, onde foi medido o diâmetro da membrana basal. RESULTADOS: Foram analisadas 66 cordas vocais, o espessamento foi identificado em 14 casos (21,2%), sendo encontrado em proporções iguais entre os sexos, sendo freqüente em pacientes da cor branca (12 casos, 85,7%). Foram encontradas alterações respiratórias em 10 (71,4%) dos casos com espessamento. Entre os pacientes intubados, 7 (18,4%) apresentaram espessamento. Entre os fumantes 9 (19,63%) apresentavam espessamento. Não houve influência estatisticamente significativa do espessamento na doença que levou o indivíduo à morte. CONCLUSÃO: Em relação a causa de morte não há diferença estatisticamente significante entre os casos cuja causa de morte foi por doenças respiratórias ou por doenças não respiratórias e o diagnóstico de espessamento da membrana basal das cordas vocais. Sua etiopatogênese necessita de maiores estudos

Beta-fibrilose encefálica e cardíaca em idosos autopsiados

INTRODUCTION: Amyloidosis in elderly individuals can be an independent alteration and a characteristic of aging. However, the clinical, pathophysiologic, and biochemical characteristics of amyloidosis related to age remain uncertain. OBJECTIVE: The purpose of this study was to determine the extent to which the heart and/or the brain of individuals aged 60 years or over exhibits amyloid deposits. MATERIALS AND METHODS: The autopsy findings of individuals who were at least 60 years old were studied. The autopsies took place between the years of 1976 and 2000. A total of 10 cases were selected that had hearts without cardiopathies, had negative serology for Chagas' disease, and had brains without morphological changes related to encephalopathies. Slides with fragments of heart and brain were processed and analyzed using polarized and common light microscopy. RESULTS: Of the 10 cases, 4 were positive for amyloidosis. All had positive findings in the brain, and 1 case also had positive findings in the heart. Among the positive cases, 50% were of people aged 60 to 69 years. There appeared to be a relationship between the presence of amyloid deposits and the ratio of brain and body weight, with the ratio in the positive cases being smaller than in the negative cases. CONCLUSIONS: The analysis of amyloid deposits in the brains and hearts of elderly individuals shows that such deposits may lead to a systemic attack of senility, common to natural aging. It is not certain that beta-amyloid deposits would alone bring such drastic repercussions to the individual. Some additional disorders of the organism could cause the breakdown of the natural balance related to the accumulation of these proteins, leading the way to the pathological contexts of amyloidosis.RESUMO INTRODUÇÃO: A amiloidose em idosos pode ser uma alteração independente e própria do envelhecimento. Entretanto, as características clínicas, fisiopatológicas e bioquímicas da Amiloidose relacionada à idade ainda permanecem incertas. OBJETIVO: Verificar se o coração e o encéfalo de indivíduos acima de 60 anos apresentavam depósito amilóide. MATERIAL E MÉTODOS: Foram estudados laudos consecutivos de autópsias de indivíduos acima de 60 anos realizadas entre 1976 e 2000, que apresentavam corações sem cardiopatias, com sorologia negativa para Doença de Chagas e encéfalos sem alterações morfológicas de encefalopatias, chegando a um n de 10 casos. Lâminas de fragmentos do coração e de encéfalo foram processadas e analisadas em microscopia de luz comum e polarizada. RESULTADOS: Dos 10 casos, 3 apresentaram depósito amilóide no encéfalo e 1 no encéfalo e no coração. Em 50% dos casos, os indivíduos tinham entre 60 e 69 anos. A relação entre o peso encefálico e o peso corporal mostrou ter uma associação significativa com os casos positivos, sendo esta menor em relação aos negativos. CONCLUSÃO: A análise conjunta de depósitos amilóides em encéfalo e coração de indivíduos idosos talvez direcione para um acometimento sistêmico comum ao envelhecimento natural. Alguma alteração adicional do organismo poderia determinar a quebra de um equilíbrio natural sobre o acúmulo dessas proteínas, levando dessa forma aos contextos patológicos da amiloidose

The Importance of C4d in Biopsies of Kidney Transplant Recipients

Antibody-mediated rejection (AMR) is highly detrimental to the prolonged survival of transplanted kidneys. C4d has been regarded as a footprint of AMR tissue damage, and the introduction of C4d staining in daily clinical practice aroused an ever-increasing interest in the role of antibody-mediated mechanisms in allograft rejection. Despite the general acceptance of the usefulness of C4d in the identification of acute AMR, the data for C4d staining in chronic AMR is variable. The presence of C4d in the majority of the biopsies with features of chronic antibody-mediated rejection is reported, but this rejection without C4d staining is observed as well, suggesting that C4d is specific but not sensitive. Further studies on AMR with positive C4d staining in biopsy specimens are really important, as well as the study of novel routine markers that may participate in the pathogenesis of this process

Widespread hematogenous metastases and Trousseau's syndrome in gastric adenocarcinoma

A case of widespread hematogenous metastases and Trousseau's syndrome is reported in a 40 year-old white housewife with gastric cancer, presenting subdural hematoma, ecchymoses, epistaxis, stomach and uterine bleeding. After undergoing hematoma drainage, she was unsuccessfully treated with platelets, red blood cells, plasma cryoprecipitate transfusions, and antibiotics. Necropsy disclosed gastric ring-signet adenocarcinoma invading the serous layer, with massive disseminated intravascular coagulation and systemic neoplastic embolism. Multiple old and recent hyaline (rich in fibrin and platelets) microthrombi, and tumor emboli were observed in the bone marrow, meninges, liver, lungs, kidneys, lymph nodes, adrenals, thyroid, heart, pancreas, and ovaries (Krukenberg tumor).Relata-se caso de metástases hematogênicas disseminadas e síndrome de Trousseau em mulher branca de 40 anos, portadora de câncer gástrico, apresentando hematoma subdural, equimoses, epistaxes, hemorragia gástrica e metrorragia. Inicialmente submetida à drenagem do hematoma, foi tratada sem sucesso com transfusões de plaquetas, hemácias e plasma crioprecipitado, além de antibióticos. O estudo de necropsia revelou adenocarcinoma gástrico com células em anel de sinete invadindo a serosa, com maciça coagulação intravascular disseminada e embolismo neoplásico sistêmico. Microtrombos hialinos (constituídos de fibrina e plaquetas) antigos e recentes, além de êmbolos tumorais, foram observados na medula óssea, meninges, fígado, pulmões, rins, linfonodos, adrenais, tireóide, coração, pâncreas e ovários (tumor de Krukenberg)

Pulmonary Innate Immune Response and Melatonin Receptors in the Perinatal Stress

Objective. To analyze the cytokines of the innate immune pulmonary response and the capacity for local response to melatonin according to the perinatal stress. Methods. 49 cases of pediatric autopsies were evaluated, divided according to cause of death, perinatal stress, gestational age, and birth weight. The percentages of IL-6, C-reactive protein (CRP), IL-1β, TNF-α, and melatonin receptor were evaluated by immunohistochemistry. Results. The IL-6 expression was higher in the children showing chronic stress, anoxia, and infection. The IL-6 expression showed a progressive increase according to the relation between weight and GA. There was no significant difference in the expression of IL-1β and TNF-α. The CRP expression was higher in the cases showing chronic stress and premature cases. The expression of melatonin receptors was significantly higher in the cases showing chronic stress, being more evident in the cases showing infection. Conclusion. The cause of death and the type of stress influence the expression in situ of melatonin and cytokines of the innate immune pulmonary response. The evaluation of IL-6 and CRP may contribute to the understanding of the evolution of neonates with chronic stress. The greater sensitivity of the lung to melatonin in these cases may indicate an attempt at controlling the immunological response, in an attempt to diminish the harmful effects of stress

Membranous nephropathy

ABSTRACT Membranous nephropathy is a glomerulopathy, which main affected target is the podocyte, and has consequences on the glomerular basement membrane. It is more common in adults, especially over 50 years of age. The clinical presentation is nephrotic syndrome, but many cases can evolve with asymptomatic non-nephrotic proteinuria. The mechanism consists of the deposition of immune complexes in the subepithelial space of the glomerular capillary loop with subsequent activation of the complement system. Great advances in the identification of potential target antigens have occurred in the last twenty years, and the main one is the protein “M-type phospholipase-A2 receptor” (PLA2R) with the circulating anti-PLA2R antibody, which makes it possible to evaluate the activity and prognosis of this nephropathy. This route of injury corresponds to approximately 70% to 80% of cases of membranous nephropathy characterized as primary. In the last 10 years, several other potential target antigens have been identified. This review proposes to present clinical, etiopathogenic and therapeutic aspects of membranous nephropathy in a didactic manner, including cases that occur during kidney transplantation

Review Article Renal Biopsy: Use of Biomarkers as a Tool for the Diagnosis of Focal Segmental Glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) is a glomerulopathy associated with nephrotic syndrome and podocyte injury. FSGS occurs both in children and adults and it is considered the main idiopathic nephrotic syndrome nowadays. It is extremely difficult to establish a morphological diagnosis, since some biopsies lack a considerable quantifiable number of sclerotic glomeruli, given their focal aspect and the fact that FSGS occurs in less than half of the glomeruli. Therefore, many biological molecules have been evaluated as potential markers that would enhance the diagnosis of FSGS. Some of these molecules and receptors are associated with the pathogenesis of FSGS and have potential use in diagnosis