972 resultados para Burrow fragments, pyritized


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J. Iberian Archaeology 13 (2010), 51-67

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Dissertação apresentada para a obtenção do Grau de Mestre em Genética Molecular e Biomedicina, pela Universidade N ova de Lisboa, Faculdade de Ciências e Tecnologia

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Chemical therapy for the treatment of leishmaniasis is still inadequate, and a number of drugs and therapeutic programs are being tested. Besides treatment, the ultimate goal is an effective cure, and histopathological analyses of the lesion cicatrices constitute an important measure of treatment success, or otherwise, in this respect. In this paper, we describe histopathological patterns in cases of American cutaneous leishmaniasis in 32 patients from the municipality of Caratinga, Minas Gerais, Brazil, before and after treatment with the following therapeutic methodos: l) leishvacin + glucantime; 2) leishvacin + BCG associated with glucantime; 3) glucantime; 4) leishvacin + BCG. Lesion fragments were collected from all patients by biopsy prior to, and approximately 30 days after, each treatment which resulted in a clinical diagnosis of cure. Following the analysis of slides, the preparations were described from a histopathological point of view and grouped taking into account the prevalence or significance of the characteristic elements. This process resulted in the following classification: 1. exsudative reaction (ER); 2. exsudative giant cell reaction (EGCR); 3. exsudative productive reaction (EPR); 4. exsudative productive giant cell reaction (EPGCR); 5. exsudative productive necrotic reaction (EPNR); 6. necrotic exsudative reaction (NER); 7. productive exsudative reaction (PER), 8. productive giant cell reaction (PGCR); 9. productive exsudative giant cell reaction (PEGCR); 10. productive exsudative giant cell granulomatous reaction (PEGCGR); 11. productive reaction (PR) and 12. productive cicatricial (cure) reaction (PCR). After this analysis, it was noted that clinical cure did not always coincide with histopathological cure.

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Canine brains infected with rabies virus were submitted to decomposition by being left at room temperature of 25 to 29oC for up to 168h. At 24h intervals, brain fragments were analyzed by immunofluorescence (IF) and by the mouse intracerebral inoculation (MI) test to confirm the diagnosis of rabies and to measure the putrefaction effect on the accuracy of the diagnosis. Forty eight h after the beginning of the experiment, the MI test showed signs of impairment with four negative results, while after 72h, 100% of the results were negative to the MI test and only one result was negative to the IF test, indicating that the threshold period for accurate diagnosis is 24 to 48h before putrefaction. The authors recommend the shipment of suspected cases of rabies to the laboratory for confirmation, but the use of putrid materials for diagnosis is meaningless because of false-negative results.

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The frequency of myocarditis associated with meningococcal disease in children was reported only in two autopsied series (United States and South Africa). Here we report the frequency of associated myocarditis in 31 children who died of meningoccal infection at Hospital Infantil N.S. da Glória in Vitória, Espirito Santo State, Brazil. The diagnosis was confirmed by isolation of Neisseria meningitidis . At least three sections of fragments of both atria and ventricles were studied using the Dallas Criteria for the morphologic diagnosis of myocarditis. The mean age was 47.6 ± 39.8 months and the mean survival time after the onset of symptoms was 46.1 ± 26.5h (12-112h). Myocarditis was present in 13 (41.9%) patients, being of minimal severity in 11 cases and of moderate severity in 2 cases. There were no cases with severe diffuse myocarditis. The frequency of myocarditis was not influenced by sex, presence of meningitis, survival time after the onset of symptoms or use of vasoactive drugs. The frequency of myocarditis reported here was intermediate between the values reported in the only two case series published in the literature (57% in the United States and 27% in South Africa). Although our data confirm the high frequency of myocaditis in meningoccal disease, further investigations are necessary to elucidate the contribution of myocarditis to myocardial dysfunction observed in cases of meningococcal infection in children.

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Optimization of the RAPD reaction for characterizing Salmonella enterica serovar Typhi strains was studied in order to ensure the reproducibility and the discriminatory power of this technique. Eight Salmonella serovar Typhi strains isolated from various regions in Brazil were examined for the fragment patterns produced using different concentrations of DNA template, primer, MgCl2 and Taq DNA polymerase. Using two different low stringency thermal cycle profiles, the RAPD fingerprints obtained were compared. A set of sixteen primers was evaluated for their ability to produce a high number of distinct fragments. We found that variations associated to all of the tested parameters modified the fingerprinting patterns. For the strains of Salmonella enterica serovar Typhi used in this experiment, we have defined a set of conditions for RAPD-PCR reaction, which result in a simple, fast and reproducible typing method.

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The formulation and use of lime mortars with ceramic particles has, in the past, been a very common technique. Knowledge of such used techniques and materials is fundamental for the successful rehabilitation and conservation of the built heritage. The durability that these mortars have shown encourages the study of the involved mechanisms, so that they may be adapted to the current reality. The considerable amount of waste from old ceramics factories which is sent for disposal might present an opportunity for the production of reliable improved lime mortars. In this paper a number of studies that characterize old building mortars containing ceramic fragments are reviewed. The most important research undertaken on laboratory prepared mortars with several heat treated clays types is presented, specifically with incorporated ceramic waste. Some studies on the pozzolanicity of heat treated clays are examined and the heating temperatures that seem most likely to achieve pozzolanicity are presented. It was verified that some heating temperatures currently used by ceramic industries might correspond to the temperatures that will achieve pozzolanicity.

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INTRODUCTION: The current prevalence of glomerulonephritis in patients with hepatosplenic schistosomiasis mansoni in Brazil was evaluated. METHODS: Sixty three patients (mean age 45.5±11 years) attending the outpatient infectious disease clinic of a University Hospital in Belo Horizonte, Brazil, from 2007 to 2009, were consecutively examined and enrolled in the present investigation. Diagnosis of hepatosplenic schistosomiasis was based on epidemiological, clinical and parasitological data and imaging techniques. Eight patients, who presented >30mg/day albuminuria, were submitted to percutaneous ultrasound guided renal biopsy. Kidney tissue fragments were examined under light, direct immunofluorescence and electron microscopy. RESULTS: All patients showed mesangial enlargement. In five, mesangial hypercellularity was observed and four presented duplication of the glomerular basement membrane. Areas of glomerular sclerosis were diagnosed in four. Deposits of immunoglobulin M and C3 were present in six samples; deposits of IgG in four, IgA in three and C1q in two samples. In all patients, immunoglobulin A was reported in the lumen of renal tubules. Deposits of kappa and lambda were observed in six samples. Electron microscopy revealed dense deposits in the glomerular tissue of three patients. Arterial hypertension, small esophageal varices, slight increases in serum creatinine and decreases in serum albumin were associated with glomerular disease. CONCLUSIONS: Renal disease associated with hepatosplenic schistosomiasis was verified in 12.7% of patients and type I membranoproliferative glomerulonephritis was observed in 50% of them. Schistosomal glomerulopathy still is an important problem in patients with hepatosplenic schistosomiasis in Brazil.

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RESUMO: O transplante hepático ortotópico é uma terapêutica aceite para casos selecionados de falência hepática terminal. O procedimento tem-­‐se aperfeiçoado, evidenciado pelo aumento da taxa de sobrevida de 30 para 75% aos 5 anos, mas cerca de 13 a 27% dos enxertos desenvolve falência primária (PNF) ou disfunção primária (DF) após o transplante. As consequências são devastadoras para a sobrevida do doente e do enxerto. A sua etiologia é multifactorial, incluindo factores relacionados com o dador e o receptor, tempos de isquémia, agressões cirúrgicas, bem como características anatomopatológicas do enxerto. A lesão de isquémia/reperfusão mantem-­‐se como um factor de risco intra operatório, com implicações directas sobre toda a evolução do transplante : existe uma relação íntima entre a PNF e a DF, a preservação do enxerto, a lesão de isquémia/reperfusão, e a falência do transplante. Além disso, está comprovada evidência que sugere que a lesão de I/R torna um aloenxerto mais vulnerável por aumento da imunogenicidade, aumentando a probabilidade de episódios de rejeição precoce e tardia. Com base na prática clínica quotidiana do CHBPT HCC, estudaram-­‐se 54 casos de transplante hepático, agrupados segundo grupos por alocação do enxerto respectivo: Grupo 1(n=27): dador cadáver para receptor cirrótico, Grupo 2 (n=15): dador cadáver para receptor PAF, Grupo 3 (n=12): dador PAF para receptor cirrótico. Observaram-­‐se as alterações histológicas e moleculares sobre o enxerto até ao final da operação do receptor, e as suas consequências clínicas,avaliando: -­‐ As diferentes capacidades de resistência e cada enxerto à lesão de isquémia/reperfusão. -­‐ As situações em que os factores do receptor se sobrepõem às do enxerto na definição do prognóstico, e vice versa. -­‐ A relevância das lesões histológicas e moleculares precoces no tecido hepático na evolução do enxerto e do receptor. Foram colhidas biópsias por agulha dos 54 enxertos hepáticos,42 provenientes de cadáver com coração batente(morte cerebral) e 12 provenientes de dador vivo com PAF, em três tempos diferentes do processo de colheita e transplante hepático: ­‐ A primeira(T0)antes da clampagem da aorta do dador -­‐ A segunda (T1) no final da isquémia fria -­‐ A terceira (T2) após a reperfusão do enxerto, durante o encerramento da parede abdominal. A estas amostras foi extraído RNA total, convertido em cDNA por transcrição reversa e feita a análise da expressão dos genes da CTLA4, IL-­‐1β, IL-­‐4, IL-­‐6, IL-­‐13, TNF-­‐α, Perforina, Selectina, (SELE), Fas-­‐ligando, Granzima-­‐B, Heme-­‐Oxigenase 1(HO1)e Óxido Nítrico Sintetase(iNOS2A)por PCR quantitativo segundo o método do Ct comparativo, utilizando como referência a expressão dos genes da amostra não-­‐isquémica –T0. Os fragmentos de todas as biópsias foram seccionados, para envio de amostra comparativa para processamento histológico habitual, sem qualquer alteração ao protocolo seguido habitualmente na Unidade de Transplantação do Hospital Curry Cabral. A presença de alguns parâmetros histológicos definidos, como esteatose, necrose, vacuolização, congestão sinusoidal e infiltração neutrofílica, foi registada e contabilizada numa classificação numérica. O seguimento clínico e laboratorial, bem como o acompanhamento de eventuais complicações, foi registado e correlacionado com os dados das colheitas de órgãos e com os dados das biópsias. Foram consideradas as seguintes variáveis, como as mais relevantes e objectivas para a interpretação da evolução clínica, tendo sido comparadas estatisticamente com os dados recolhidos, laboratoriais e clínicos: disfunção do enxerto, 207 pós operatórias, número de internamentos igual ou superior a 2 e rejeição crónica e/ou morte do receptor. Foram identificadas características clínicas menos favoráveis, a considerar, nalgumas circunstâncias: género feminino do receptor (sobretudo associado a enxerto masculino, p=0,077), isquémia fria superior a 500 minutos (p=0,074), isquémia quente superior a 90 minutos (p=0,099). Na análise laboratorial, distinguiram-­‐se duas características histológicas desfavoráveis e irreversíveis, como índice de mau prognóstico: a necrose e a balonização (p=0,029); no painel genético escolhido neste estudo,a expressão basal de IL-­‐1β(p=0,028), de SELE p=0,013)e de FAS-­‐L (p=0,079)relacionaram-­‐se com pior prognóstico. Algumas características protectoras intrínsecas dos enxertos só se revelaram indirectamente, como menor infiltração neutrofílica e maior expressão de HO1 e de iNOS nos enxertos PAF, não tendo sido possível provar uma interferência directa nos resultados clínicos. Não se obteve expressão mensurável de genes anti-­‐ inflamatórios nas biopsias hepáticas processadas neste estudo, como a IL13 e a I 4: assim, com a metodologia utilizada, não foi possível obter um perfil de expressão genética associado a boa evolução clínica. O perfil inverso foi sugerido apenas pela expressão basal dos 3 genes mencionados (FAS-­‐L,IL-­‐1β e SELE)no mesmo painel, com o protocolo seguido neste conjunto de 54 doentes. As características do receptor sobrepuseram-­‐se às do enxerto no caso de: -­‐ diagnóstico de PAF no receptor, que determinou uma maior predisposição para a disfunção do enxerto, o que, por sua vez, determina uma menor sobrevida. No entanto, o diagnóstico de PAF no receptor exibe uma curva de sobrevida mais favorável. -­‐ receptores com um baixo balanço de risco (BAR)definiram características favoráveis para enxertos com níveis baixos e moderados de esteatose, fazendo que esta característica, definida como um risco acrescido, não só não se manifestasse clinicamente,como parecesse um factor favorável. As características do enxerto sobrepuseram-­‐se às do receptor no caso de: -­‐ tempo de isquémia fria superior a 500 minutos -­‐ balonização, necrose, FAS-­‐L,IL-­‐1β e SELE em T0 A integração dos resultados moleculares e morfológicos com a evolução clínica, realça o papel da mobilização precoce de neutrófilos nos desempenhos menos favoráveis do enxerto hepático. -------------ABSTRACT: Orthotopic liver transplantation is na accepted therapeutic procedure for selected cases of terminal liver failure. The procedure has been improved, evidenced by the rise of survival rates from 30 to 70% at 5 years, but 13 to 27% of the liver grafts develops primary non function (PNF) or primary dysfunction (PDF) after transplantation. The consequences are devastating for the survival of the patient and of the graft. Its etiology is multifactorial, including factos related with the donor and with the recipient, ischemic times, surgical aggressions, as well as the histological characteristics of the graft. The ischemia/reperfusion lesion is still an intraoperative risk factor, with direct implications in the whole transplant outcome: there is a close interrelation between PNF and DF, graft preservation, ischemia / reperfusion lesion and graft failure. Beyond his, there is proved evidence that suggests that I/R lesion turns the allograft more vulnerable by increasing its immunogenity, increasing the probability of precocious and late rejection episodes. Based on the daily clinical practice at CHBPT /HCC, 54 cases of hepatic transplantation have been studied, grouped by allocation of each graft: Group (n=27):deceased do nortocirrhotic recipient, Group 2 (n=15): deceased donor to FAP recipient, Group 3 (n=12): FAP living donor to cirrhotic recipient. The histologic and molecular changes in the liver graft were observed until the end of the recipiente operation,together with its clinical consequences, evaluating:-­‐The different capacity of resistance of each graft to the ischemia / reperfusion lesion -­‐ The situations where the recipiente factos overlap the ones of the graft, in the definition of prognosis, and vice versa.-­‐ The relevance of the precocious histologic and molecular lesions of the hepatic tissue in the clinical outcome of the graft and the recipient. Needle biopsies were obtained from 54 liver grafts, 42 deceased brain dead donors and 12 from FAP living donors, at three diferente times of the harvesting and the hepatic transplantation: The first one (T0) before clamping the donor aorta -­‐ The second one (T2) in the end of cold ischemia time -­‐ The third one (T) after the reperfusion of the graft, during the closure of the abdominal wall. Total RNAwas extracted to these samples, converted to cDNA by reverse transcription and the analysis of gene expression was made for CTLA4,IL-­‐1β,IL-­‐4,IL-­‐6,IL-­‐13,TNF-­‐α,Perforin,E Selectin (SELE),Fas-­‐ligand,Granzyme-­‐B,Heme-­‐oxigenase 1 (HO1) and Nitric Oxide Sintetase (iNOS2A) by quantitative PCR, according with the Ct comparative method, using the expression of the non ischemic sample – T0. The fragments of all the biopsies were divided, to send a comparative sample to the usual histologic processement, keeping the same usual protocol at the Transplantation Unit of Curry Cabral Hospital. The presence of some defined histologic parameters, such as steatosis, necrosis, vacuolization, sinusoidal congestion and neutrophilic infiltration, was registered and catalogued in a numeric classification. The clinical and laboratory follow-­‐up, as well as the following of eventual complications, was registered and correlated with the data from organ procurement operations and with the data from the biopsies. The following variables were considered as the most relevant and objective ones, to the interpretation of the clinical evolution, being statistically compared with the clinical and laboratorial collected data: graft dysfunction, post-­‐operative complications, number of readmissions of 2 or more and chronic rejection and /or recipiente death. There were identified some unfavorable clinical characteristics, to be considered under certain circumstances: recipiente female gender (specially associated with malegraft, p=0,077), cold ischemia time of more than 500 minutes (p=0,074), warm ischemia time of more than 90 minutes (p=0,099). In the laboratory analysis, two histologic characteristics were identified as unfavorable and irreversible, associated with bad prognosis: necrosis and balonization (p=0,029); in the gene panel selected in this study, the basal expression of IL-­‐1β (p=0,028), SELE (p=0,013) and FAS-­‐L (p=0,079)were related with worse prognosis.Some intrinsic protective characteristics of the grafts were only indirectly revealed, such as less neutrophilic infiltration and bigger expression of HO1 and iNOS in FAP grafts, being impossible to prove any direct inte ference in the clinical results. A relevant and measurable expression of the anti inflammatory genes IL13 and IL4 was not obtained: with the used methodology, it was impossible to obtain a gene expression profile associated with a favorable clinical outcome.The inverse profile was suggested only by the basal expression of the three mentioned genes (FAS-­‐L, IL-­‐ 1β e SELE) in the same gene panel, according with the followed protocol in this group of 54 patients. The characteristics of the recipient overlapped those from the graft, in the case of :-­‐ FAP diagnosis in the recipient, which determined a bigger predisposition to graft dysfunction, which by itself determines a shorter survival. However, FAP diagnosis in the recipiente depicts a more favorable survival curve. -­‐ Recipients with a low balance risk índex (BAR) defined favorable characteristics to grafts with low and moderate grades of steatosis, making that this characteristic, associated with bad prognosis, looked like a favorable factor, and with no clinical interference. The graft characteristics overlapped those from the receptor in the case of: -­‐ Cold ischemic time more than 500 minutes -­‐ Balonization, necrosis, FAS-­‐L, IL-­‐1β and SELE at T0. The integration of molecular and morphologic results with the clinical evolution, stresses the role of a precocious neutrophils mobilization in the worse outcomes of liver grafts.

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INTRODUCTION: Opportunistic fungal infections in immunocompromised hosts are caused by Candida species, and the majority of such infections are due to Candida albicans. However, the emerging pathogen Candida dubliniensis demonstrates several phenotypic characteristics in common with C. albicans, such as production of germ tubes and chlamydospores, calling attention to the development of stable resistance to fluconazole in vitro. The aim of this study was to evaluate the performance of biochemistry identification in the differentiating between C. albicans and C. dubliniensis, by phenotyping of yeast identified as C. albicans. METHODS: Seventy-nine isolates identified as C. albicans by the API system ID 32C were grown on Sabouraud dextrose agar at 30°C for 24-48h and then inoculated on hypertonic Sabouraud broth and tobacco agar. RESULTS: Our results showed that 17 (21.5%) isolates were growth-inhibited on hypertonic Sabouraud broth, a phenotypic trait inconsistent with C. albicans in this medium. However, the results observed on tobacco agar showed that only 9 (11.4%) of the growth-inhibited isolates produced characteristic colonies of C. dubliniensis (rough colonies, yellowish-brown with abundant fragments of hyphae and chlamydospores). CONCLUSIONS: The results suggest that this method is a simple tool for screening C. albicans and non-albicans yeast and for verification of automated identification.

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Flavivirus is a genus of arthropod-transmitted viruses of the family Flaviviridae, and in Brazil, up to eleven different Flavivirus have been isolated. We collected blood from farmers in the municipality of Theobroma, which is located 320km from the City of Porto Velho, the former capital of the Brazilian State of Rondônia. For viral isolation, we used newborn mouse brain, followed by RT-PCR with specific universal Flavivirus primers. We obtained fragments 958bp and 800bp in length. Based on BLAST, these sequences were 91% similar to a sequence of Cacipacore virus.

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INTRODUCTION: The aim of this work was to evaluate the prevalence of Mycobacterium tuberculosis (MT) strains with mutations that could result in resistance to the main drugs used in treatment in a region with one of the highest numbers of tuberculosis (TB) cases in southern Brazil. METHODS: Deoxyribonucleic acid (DNA) from 120 sputum samples from different patients suspicious of pulmonary tuberculosis who attended the Municipal Public Laboratory for Mycobacterium sp. diagnosis was directly amplified and analyzed by PCR-SSCP. The DNA was amplified in known hotspot mutation regions of the genes rpoB, ahpC, embB, katG, inhA, and pncA. RESULTS: The percentage of samples positive by culture was 9.2% (11/120); 5% (6/120) were positive by bacilloscopy and MT-PCR, and DNA fragments of the aforementioned resistance genes could be amplified from seven (7) of the eleven (11) samples with positive results, either by culture or PCR/bacilloscopy. All presented a SSCP pattern similar to a native, nonresistant genotype, with the ATCC strain 25177 as control, except for one sample (0.01%), which presented a SSCP profile demonstrating mutation at the embB gene. CONCLUSIONS: These results are consistent with the empirical observations by physicians treating TB patients in our region of a low occurrence of cases that are refractory to conventional treatment schemes, in contrast to other parts of the country. Continued surveillance, especially molecular, is essential to detect and monitor the outbreak of MT-resistant strains.

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INTRODUCTION: Staphylococcal species are pathogens that are responsible for outbreaks of foodborne diseases. The aim of this study was to investigate the prevalence of enterotoxin-genes and the antimicrobial resistance profile in staphylococcus coagulase-negative (CoNS) and coagulasepositive (CoPS) isolates from black pudding in southern Brazil. METHODS: Two hundred typical and atypical colonies from Baird-Parker agar were inoculated on mannitol salt agar. Eighty-two mannitol-positive staphylococci were submitted to conventional biochemical tests and antimicrobial susceptibility profiling. The presence of coagulase (coa) and enterotoxin (se) genes was investigated by polymerase chain reaction. RESULTS: The isolates were divided into 2 groups: 75.6% (62/82) were CoNS and 24.4% (20/82) were CoPS. The biochemical tests identified 9 species, of which Staphylococcus saprophyticus (37.8%) and Staphylococcus carnosus (15.9%) were the most prevalent. Antimicrobial susceptibility tests showed resistance phenotypes to antibiotics widely administered in humans, such as gentamicin, tetracycline, chloramphenicol, and erythromycin. The coa gene was detected in 19.5% (16/82) of the strains and 4 polymorphic DNA fragments were observed. Five CoNS isolates carrying the coa gene were submitted for 16S rRNA sequencing and 3 showed similarity with CoNS. Forty strains were positive for at least 1 enterotoxin-encoding gene, the genes most frequently detected were sea (28.6%) and seb (27.5%). CONCLUSIONS: The presence of antimicrobial resistant and enterotoxin-encoding genes in staphylococci isolates from black pudding indicated that this fermented food may represent a potential health risk, since staphylococci present in food could cause foodborne diseases or be a possible route for the transfer of antimicrobial resistance to humans.

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INTRODUCTION: Authors describe human schistosomal granuloma in late chronic phase, from the morphological and evolutionary viewpoints. METHODS: The study was based on a histological analysis of two fragments obtained from a surgical biopsy of peritoneum and large intestine of a 42-year-old patient, with a pseudotumoral form mimicking a peritoneal carcinomatosis associated to the schistosomiasis hepatointestinal form. RESULTS: Two hundred and three granulomas were identified in the pseudotumor and 27 in the intestinal biopsy, with similar morphological features, most in the late chronic phase, in fibrotic healing. A new structural classification was suggested for granulomas: zone 1 (internal), 2 (intermediate) and 3 (external). CONCLUSIONS: Regarding granuloma as a whole, we may conclude that fibrosis is likely to be controlled by different and independent mechanisms in the three zones of the granuloma. Lamellar fibrosis in zone 3 seems to be controlled by matrix mesenchymal cells (fibroblasts and myoepithelial cells) and by inflammatory exudate cells (lymphocytes, plasmocytes, neutrophils, eosinophils). Annular fibrosis in zone 2, comprising a dense fibrous connective tissue, with few cells in the advanced phase, would be controlled by epithelioid cells involving zone 1 in recent granulomas. In zone 1, replacing periovular necrosis, an initialy loose and tracery connective neoformation, housing stellate cells or with fusiform nuclei, a dense paucicellular nodular connctive tissue emerges, probably induced by fibroblasts. In several granulomas, one of the zones is missing and granuloma is represented by two of them: Z3 and Z2, Z3 and Z1 or Z2 and Z1 and, ultimately, by a scar.

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Introduction Leishmania braziliensis infection induces a large spectrum of lesions that clinically manifest as nodules or papules that progress to ulcers. Although it is already known that T helper cells predominate in the lesions, cytotoxic T cells have also been reported to be present, and their role in leishmaniasis immunopathogenesis is not well known. This study investigated the amounts of CD8+ and granzyme B+ cells in different clinical forms of human cutaneous leishmaniasis (CL). Methods Forty tissue fragments from early (E-CL) and late CL (L-CL) lesions and from disseminated leishmaniasis (DL) - papules and ulcers - were characterized. The inflamed area per fragment was calculated, and the CD8 and granzyme B expression levels in the infiltrates were quantified by counting positive cells in 15 fields. The localization of CD8 and granzyme B was graded subjectively. Results Inflammation was higher in L-CL and DL ulcers. CD8 expression was increased in late ulcerated lesions compared to recent lesions. The increase in CD8+ cells also correlated with the duration of the lesion. Papules had a higher frequency of granzyme B+ cells than E-CL lesions, although the frequency was similar to those for late and DL ulcers. CD8+ cells were mostly found in the papillary dermis. Conclusions CD8+ T and granzyme B+ cells are present in the inflammatory infiltrates of CL and DL and may participate in the immunopathogenesis of Leishmania infection.