44 resultados para Embedded subtrees
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Cystic echinococcosis (CE) is a globally parasitic zoonosis caused by larval stages of Echinococcus granulosus. This study investigated E. granulosus genotypes isolated from livestock and humans in the Golestan province, northern Iran, southeast of the Caspian sea, using partial sequencing data of the cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase 1 (nad1) mitochondrial genes. Seventy E. granulosus isolates were collected from animals in slaughterhouses: 18 isolates from sheep, 40 from cattle, nine from camels, two from buffaloes and one from a goat, along with four human isolates (formalin-fixed, paraffin-embedded tissues) from CE patients of provincial hospitals. All isolates were successfully analysed by PCR amplification and sequencing. The sequence analysis found four E. granulosus genotypes among the 74 CE isolates: G1 (78.3%), G2 (2.7%), G3 (15%) and G6 (4%). The G1-G3 complex genotype was found in all of the sheep, goat, cattle and buffalo isolates. Among the nine camel isolates, the frequency of G1-G3 and G6 genotypes were 66.7% and 33.3%, respectively. All four human CE isolates belonged to E. granulosus sensu stricto. This study reports the first occurrence of the G2 genotype in cattle from Iran and confirms the previously reported G3 genotype in camels in the same country.
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Vibrio cholerae represents a significant threat to human health in developing countries. This pathogen forms biofilms which favors its attachment to surfaces and its survival and transmission by water or food. This work evaluated the in vitro biofilm formation of V. cholerae isolated from clinical and environmental sources on stainless steel of the type used in food processing by using the environmental scanning electron microscopy (ESEM). Results showed no cell adhesion at 4 h and scarce surface colonization at 24 h. Biofilms from the environmental strain were observed at 48 h with high cellular aggregations embedded in Vibrio exopolysaccharide (VPS), while less confluence and VPS production with microcolonies of elongated cells were observed in biofilms produced by the clinical strain. At 96 h the biofilms of the environmental strain were released from the surface leaving coccoid cells and residual structures, whereas biofilms of the clinical strain formed highly organized structures such as channels, mushroom-like and pillars. This is the first study that has shown the in vitro ability of V. cholerae to colonize and form biofilms on stainless steel used in food processing.
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In Brazil, a high prevalence of cytomegalovirus (CMV) infection has been documented. In immunocompetent adults CMV infection is usually asymptomatic and therefore morphologic and immunophenotypic bone marrow changes have rarely been described. The authors report the case of a previously healthy patient who developed fever of undetermined origin. The diagnosis of acute CMV infection was based on serological testing. A computed tomographic scan showed mediastinal lymphadenopathy. A bone marrow biopsy revealed a hypercellular haematopoiesis with eosinophilia and large mixed T- and B-cell lymphoid aggregates. In spite of bcl-2 positivity, their reactive nature was demonstrated. Polymerase chain reaction (PCR) and immunohistochemistry were unable to detect CMV-DNA in paraffin-embedded bone marrow sections. Much like in other systemic disorders, the lymphoid nodules in this case seemed to be caused by immunological mechanisms, possibly due to cytokines released in response to the systemic infectious process.
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A morphometric study of the circular colon musculature was performed, in which the mast cell count was determined and the connective fibrous tissue in this layer was measured. The objective was to gain better understanding of Chagas megacolon morphology and contribute towards the knowledge of fibrosis pathogenesis in Chagas megas. An evaluation was made of 15 distal sigmoid rings from Chagas patients with megacolon (MCC), 15 without megacolon (CSMC) and 15 non-Chagas patients (NC). The rings were fixed in formol, embedded in paraffin, and 7mm thick sections were cut and stained using Azan-Heidenhain and Giemsa. The mast cell count and fibrosis were greater in the MCC group than in the CSMC and NC groups (p < 0.05; Kruskal-Wallis test) and there was no significant difference between the latter two. The fibrosis and increased mast cell count in the colon musculature of the MCC group possibly indicates that there is a relationship between mastocytosis and fibrosis, as has already been demonstrated in other pathologies.
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Introduction The progression of human papillomavirus (HPV) infection in the anogenital tract has been associated with the involvement of cells with regulatory properties. Evidence has shown that glucocorticoid-induced tumor necrosis factor receptor (GITR) is an important surface molecule for the characterization of these cells and proposes that GITR ligand may constitute a rational treatment for many cancer types. We aimed to detect the presence of GITR and CD25 in cervical stroma cells with and without pathological changes or HPV infection to better understand the immune response in the infected tissue microenvironment. Methods We subjected 49 paraffin-embedded cervical tissue samples to HPV DNA detection and histopathological analysis, and subsequently immunohistochemistry to detect GITR and CD25 in lymphocytes. Results We observed that 76.9% of all samples with high GITR expression were HPV-positive regardless of histopathological findings. High GITR expression (77.8%) was predominant in samples with ≥1,000 RLU/PCB. Of the HPV-positive samples negative for intraepithelial lesion and malignancy, 62.5% had high GITR expression. High GITR expression was observed in both carcinoma and high-grade squamous intraepithelial lesion (HSIL) samples (p = 0.16). CD25 was present in great quantities in all samples. Conclusions The predominance of high GITR expression in samples with high viral load that were classified as HSIL and carcinoma suggests that GITR+ cells can exhibit regulatory properties and may contribute to the progression of HPV-induced cervical neoplasia, emphasizing the importance of GITR as a potential target for immune therapy of cervical cancer and as a disease evolution biomarker.
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ABSTRACTINTRODUCTION: In the Americas, mucosal leishmaniasis is primarily associated with infection by Leishmania (Viannia) braziliensis. However, Leishmania (Viannia) guyanensis is another important cause of this disease in the Brazilian Amazon. In this study, we aimed at detecting Leishmaniadeoxyribonucleic acid (DNA) within paraffin-embedded fragments of mucosal tissues, and characterizing the infecting parasite species.METHODS: We evaluated samples collected from 114 patients treated at a reference center in the Brazilian Amazon by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses.RESULTS: Direct examination of biopsy imprints detected parasites in 10 of the 114 samples, while evaluation of hematoxylin and eosin-stained slides detected amastigotes in an additional 17 samples. Meanwhile, 31/114 samples (27.2%) were positive for Leishmania spp. kinetoplast deoxyribonucleic acid (kDNA) by PCR analysis. Of these, 17 (54.8%) yielded amplification of the mini-exon PCR target, thereby allowing for PCR-RFLP-based identification. Six of the samples were identified as L. (V.) braziliensis, while the remaining 11 were identified as L. (V.) guyanensis.CONCLUSIONS: The results of this study demonstrate the feasibility of applying molecular techniques for the diagnosis of human parasites within paraffin-embedded tissues. Moreover, our findings confirm that L. (V.) guyanensisis a relevant causative agent of mucosal leishmaniasis in the Brazilian Amazon.
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Mutations at codons 12, 13, or 61 of the H-ras, K-ras, and N-ras have been detected in human neoplasias by a variety of techniques. Some of these techniques are very sensitive and can detect K-ras mutation in 90% of the cases of pancreatic adenocarcinomas. We analyzed 11 samples of pancreatic adenocarcinoma, three samples of pancreatic mucinous cystadenoma, and two samples without tumors in formalin-fixed paraffin embedded tissue sections. K-ras mutations at codon 12 were detected by a two-step PCR-enriched technique in all the samples of pancreatic adenocarcinoma, but not in cystadenoma or control samples. This technique may be useful for early detection of pancreatic cancer.
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The rejection of allotransplantation of epigastric microsurgical flaps and the effect of immunosuppression have been studied in 58 rats. Three sets of experiments were planned: (1) Wistar Furth isogenic donors and receptors (control set); (2) Brown Norway donors and Wistar Furth receptors (rejection set); and (3) Brown Norway donors and Wistar Furth immunosuppressed receptors (cyclosporin A set). Cyclosporin A (10 mg/kg/d) treated rats had a transplantation survival rate of up to 30 days: 83.3% among isogenic animals and 60% among allogeneic. There was 100% rejection by the 9th day after the transplantation in allogeneic non-immunosuppressed rats. Biopsies embedded with historesin were taken from the flap and normal contralateral skin (used as control) on the 3rd, 7th, 15th, and 30th days after the surgery. A quantitative study of infiltrating lymphocytes in the flaps, with and without cyclosporin A, was done by evaluating the local inflammatory infiltrate. A significant increase in the number of lymphocytes among the rejection and immunosuppressed groups was seen, as compared to the isogenic set. Local lymphocytosis in allogeneic non-immunosuppressed transplantations reached its highest level on the 3rd day after surgery, before gross findings of rejection, which could only be seen by naked eye on the 5th or 6th day. Therefore, we conclude that cyclosporin A is effective in preserving allogenic transplantation in rats. Biopsies of transplanted areas may contribute to earlier diagnosis of the need for immunosuppressive therapy.
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Seed dispersal of Hymenaea courbaril was studied by following the fate of 585 seeds embedded with small magnets and set in displays in and near a logged strip in rain forest in the Peruvian Amazonian. Mammals took fruits from all displays, which were located in the forest, edge, and cleared strip. Overall removal rates were low - a median of 8.1 fruits / month from displays maintained with 8-10 fruits - but were higher in August than in earlier months. Most fruits were dropped near the display or had their seeds eaten, but > 13% were successfully dispersed. Most of the dispersed seeds were buried, which increases probability of germination. Maximum dispersal distance of live seeds was 12.1 m (median 3.1 m), but other magnets were transported up to 34 m, indicating seeds were dispersed further, but then eaten. Acouchies (most likely Myoprocta pratti) and agoutis (Dasyprocta fuliginosa) were apparently the main dispersal agents. Dispersal of seeds from the forest into the logged strip was rare, suggesting that although rodents disperse H. courbaril, they cannot be relied on for the reseeding this and similar species in recent clearings.
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OBJECTIVE: To study the arrangement of the myocardial fiber bundles at the pulmonary venous left atrial junction in patients with pulmonary hypertension, and to discuss the pathophysiological importance of this element in the etiology of acute pulmonary edema. METHODS: We obtained 12 hearts and their pulmonary vein extremities from postmortem examinations of patients with the anatomicopathological diagnosis of acute pulmonary edema. The specimens, which had no grossly visible morphological cardiac alterations, were fixed in 10% formalin, and the muscular arrangement of the pulmonary venous left atrial junctions was analyzed. This material was then isolated, embedded in paraffin, underwent serial cutting (50 µm of thickness), and was stained with Azam's trichrome. RESULTS: We observed in our specimens that: a) the myocardial fiber bundles that originate in the atrial wall and involve the openings of the pulmonary veins were fewer than those observed in healthy material; b) the myocardial fiber bundles that extend into the pulmonary veins were shorter than those found in material originating from individuals with no pulmonary hypertension. CONCLUSION: Anatomical changes that result in a reduction in the amount of myocardial fiber bundles in the pulmonary venous left atrial junction, isolated or associated with other factors, may be the cause of disorders in pulmonary circulation, leading to an increase in pulmonary venous pressure, and, consequently, to acute pulmonary edema.
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A detailed description of the morphology of the digestive organs of Enteroctopus megalocyathus (Gould, 1852) and Loligo sanpaulensis Brakoniecki, 1984 is given. The mandibles, the crop diverticulum, a doubly coiled caecum, the loop of the medium intestine and the appendages of the digestive gland are first described for E. megalocyathus. The most outstanding finding in L. sanpaulensis is the location of the single posterior salivary gland, wholly embedded in the digestive gland.
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The presence of viral antigen in sections from formalin-fixed and paraffin-embedded human tissues was demonstrated by trypsin digestion followed by direct or indirect immunofluorescence. The specimens may be used for retrospective diagnosis. The immunofluorescence technique has to be adapted to the suspected virus infection on the basis of previous histopathology study. Variations of trypsin concentration time and temperature of incubation, expose different viral antigens and have to be previously tested for each unknown system. For measles virus detection in lung a stronger digestion has to be applied as compared to adenovirus or respiratory disease viruses in the same tisue. Flavivirus in liver tissue needs a weaker digestion. The reproducibility of the method makes it useful as a routine technique in diagnosis of virus infection.
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This paper deals with the morphology of Pomacea caniculata (Lamarck, 1822) collected at Corrientes, Argentina. Comparison is made with Pomacea lineata (Spix, 1827) and Pomacea sordida (Swainson, 1823). The shell is globose, heavy, with greenish or horn-colored periostracum and dark spiral bands; apex subelevated, 5-6 whorls increasing rather rapidly and separated by very deep suture. Aperture large, rounded to subelongated; lip sometimes reddish; umbilicus large and deep; operculum corneous, entirely closing the aperture. Ratios: shell width/shell length = 0.78-0.96 (mean 0.86); aperture length/shell length = 0.68-0.77 (mean 0.72). Radula similar to other congeneric species. Testis and spermiduct as in P. lineata and P. sordida; prostate cylindric and short, cream in color as the testis. Penial sheath straight bearing a central outer gland deeply embedded in the tissue of its basal portion and a large wrinkled gland occupying 2/3 of the distal tip of its inner surface; the rigth margin of the sheath overlaps the left one until 2/3 of its proximal end. Female reproductive apparatus similar to that P. lineata; vestigial male copulatory apparatus (penis and its sheath) present in all females examined.
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Pulmonary lesions compatible with adenovirus infection were detected by gross and microscopic examination of autopsy tissues children aged from 5 to 34 months. Hepatic lesions indicative of systemic infection were also found in four of the chisldren. The viral etiology was confirmed in three cases by in-situ hibridization, electro-microscopy and immunofluorescence performed in parafin-embedded tissues, and in one case by cell culture isolation of adenovirus type 2 from nasopharyngeal exudate. Routine testing by methods additional to conventional light microscopy would probably have revealed a larger number of adenovirus infections among the 1.103 autopsy records analyzed in this study.
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A hundred-sixty paraffin-embedded specimens from female cervical lesions were examined for human papillomavirus (HPV) types 6, 11, 16 and 18 infections by non-isotopic in situ hybridization. The data were compared with histologic diagnosis. Eighty-eight (55) biopsies contained HPV DNA sequences. In low grade cervical intraepithelial neoplasias (CIN I), HPV infection was detected in 78.7 of the cases, the benign HPV 6 was the most prevalent type. HPV DNA was detected in 58 of CIN II and CIN III cases and in 41.8 of squamous cell carcinomas (SCC). Histologically normal women presented 20 of HPV infection. Oncogenic HPV was found in 10 of these cases, what may indicate a higher risk of developing CINs and cancer. Twenty-five percent of the infected tissues contained mixed infections. HPV 16 was the most common type infecting the cervix and its prevalence raised significantly with the severity of the lesions, pointing its role in cancer pathogenesis. White women presented twice the cervical lesions of mulatto and African origin women, although HPV infection rates were nearly the same for the three groups (approximately 50). Our results showed that HPV typing by in situ hybridization is a useful tool for distinguishing between low and high risk cervical lesions. Further studies are required to elucidate risk factors associated with HPV infection and progression to malignancy in Brazilian population.