94 resultados para HEPATIC STELLATE CELLS
Resumo:
INTRODUCTION: The innate immune response is the first mechanism of protection against Trypanosoma cruzi, and the interaction of inflammatory cells with parasite molecules may activate this response and modulate the adaptive immune system. This study aimed to analyze the levels of cytokines and chemokines synthesized by the whole blood cells (WBC) and peripheral blood mononuclear cells (PBMC) of individuals seronegative for Chagas disease after interaction with live T. cruzi trypomastigotes. METHODS: IL-12, IL-10, TNF-α, TGF-β, CCL-5, CCL-2, CCL-3, and CXCL-9 were measured by ELISA. Nitrite was determined by the Griess method. RESULTS: IL-10 was produced at high levels by WBC compared with PBMC, even after incubation with live trypomastigotes. Production of TNF-α by both PBMC and WBC was significantly higher after stimulation with trypomastigotes. Only PBMC produced significantly higher levels of IL-12 after parasite stimulation. Stimulation of cultures with trypomastigotes induced an increase of CXCL-9 levels produced by WBC. Nitrite levels produced by PBMC increased after the addition of parasites to the culture. CONCLUSIONS: Surface molecules of T. cruzi may induce the production of cytokines and chemokines by cells of the innate immune system through the activation of specific receptors not evaluated in this experiment. The ability to induce IL-12 and TNF-α contributes to shift the adaptive response towards a Th1 profile.
Resumo:
INTRODUCTION: The capacity to overcome the oxidative stress imposed by phagocytes seems to be critical for Candida species to cause invasive candidiasis. METHODS: To better characterize the oxidative stress response (OSR) of 8 clinically relevant Candida sp., glutathione, a vital component of the intracellular redox balance, was measured using the 5,5'-dithiobis-(2-nitrobenzoic acid (DTNB)-glutathione disulfide (GSSG) reductase reconversion method; the total antioxidant capacity (TAC) was measured using a modified method based on the decolorization of the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic) acid radical cation (ABTS*+). Both methods were used with cellular Candida sp. extracts treated or not with hydrogen peroxide (0.5 mM). RESULTS: Oxidative stress induced by hydrogen peroxide clearly reduced intracellular glutathione levels. This depletion was stronger in Candida albicans and the levels of glutathione in untreated cells were also higher in this species. The TAC demonstrated intra-specific variation. CONCLUSIONS: Glutathione levels did not correlate with the measured TAC values, despite this being the most important non-enzymatic intracellular antioxidant molecule. The results indicate that the isolated measurement of TAC does not give a clear picture of the ability of a given Candida sp. to respond to oxidative stress.
Resumo:
INTRODUCTION: To analyze the liver dysfunction and evolution of signs and symptoms in adult dengue patients during a two-month follow-up period. METHODS: A prospective cohort study was conducted in Campos dos Goytacazes, Rio de Janeiro, Brazil, from January to July, 2008. The evolution of laboratory and clinical manifestations of 90 adult dengue patients was evaluated in five scheduled visits within a two-month follow-up period. Twenty controls were enrolled for the analysis of liver function. Patients with hepatitis B, hepatitis C, those known to be human immunodeficiency virus (HIV) seropositive and pregnant women were excluded from the study. RESULTS: At the end of the second month following diagnosis, we observed that symptoms persisted in 33.3% (30/90) of dengue patients. We also observed that, 57.7% (15/26) of the symptoms persisted at the end of the second month. The most persistent symptoms were arthralgia, fatigue, weakness, adynamia, anorexia, taste alteration, and hair loss. Prior dengue virus (DENV) infection did not predispose patients to a longer duration of symptoms. Among hepatic functions, transaminases had the most remarkable elevation and in some cases remained elevated up to the second month after the disease onset. Alanine aminotransferase (ALT) levels overcame aspartate aminotransferase (AST) during the convalescent period. Male patients were more severely affected than females. CONCLUSIONS: Dengue fever may present a wide number of symptoms and elevated liver transaminases at the end of the second month.
Resumo:
INTRODUCTION: Little is known about the early events in the interaction between Paracoccidioides brasiliensis and its host. To understand the effect of carbohydrates in the interaction between the fungus and epithelial cell in culture, we analyzed the influence of different carbohydrate solutions on the adhesion of P. brasiliensis yeast cells to CCL-6 cells in culture. METHODS: Fungal cells were cultivated with the epithelial cell line, and different concentrations of D-fucose, N-acetyl-glucosamine, D-mannose, D-glucosamine, D-galactosamine, sorbitol and fructose were added at the beginning of the experiment. Six hours after the treatment, the cells were fixed and observed by light microscopy. The number of P. brasiliensis cells that were adhered to the CCL-6 monolayer was estimated. RESULTS: The number of adhesion events was diminished following treatments with D-fucose, N-acetyl-glucosamine, D-mannose, D-glucosamine and D-galactosamine as compared to the untreated controls. Sorbitol and fructose-treated cells had the same adhesion behavior as the observed in the control. P. brasiliensis propagules were treated with fluorescent lectins. The FITC-labeled lectins WGA and Con-A bound to P. brasiliensis yeast cells, while SBA and PNA did not. CONCLUSIONS: The perceptual of adhesion between P. brasiliensis and CCL-6 cells decreased with the use of D-mannose, N-acetyl-glucosamine and D-glucosamine. The assay using FITC-labeled lectins suggests the presence of N-acetyl-glucosamine, α-mannose and α-glucose on the P. brasiliensis cell surface. An enhanced knowledge of the mediators of adhesion on P. brasiliensis could be useful in the future for the development of more efficient and less harmful methods for disease treatment and control.
Resumo:
Echinococcosis/hydatidosis is common in societies where agriculture and livestock are frequent, and represents a public health problem. The therapeutic management depends on the cyst's characteristics, the patient, and surgical contraindications. Endoscopic retrograde cholangiopancreatography is a valuable tool in the diagnosis and treatment of complicated hepatic hydatid disease. Ultrasonography is a useful diagnostic, therapeutic and follow-up tool. The authors report a case of a 56 years old patient who was diagnosed with a hepatic hydatid cyst in the IVa/VIII segments, describe the therapeutic options and 50 months of disease-free follow-up.
Resumo:
Visceral leishmaniasis (VL) or kala-azar, a disseminated infection of the lymphoreticular system of the body, is marked by severe defect in immune system of the host. Successful cure of VL depends on the immune status of the host in combination with the effects of the antileishmanial drugs. The rationale approach towards eradication of this disease would be to potentiate the immune functioning of the host in addition to parasite killing. This review deals with different aspects of adaptive and innate immune responses and explores their role in protection or pathogenesis of VL. IL-10 has emerged as the principal cytokine responsible for disease pathogenesis, although evidences regarding its source during active VL remain inconclusive. On the other hand, IFNγ, under the influence of IL-12, is mostly correlated with healing of the disease. Chemokines are important in mounting cell-mediated immune response as they can prevent parasite invasion in association with cytokines. Different types of T cells like CD4, CD8 and NK T cells also contribute to the immunology of this disease. In spite of conflicting reports, the role of regulatory T cells in VL pathogenesis is important. Recently discovered Th17 subset and its different members have been reported to perform diverse functions in the course of VL and leishmaniasis as a whole. Innate immune responses, depending on the cell types, are essential in early parasite detection and subsequent development of an efficient NK cell response. Immunotherapy targeting IL-10 could be looked upon as an interesting option for the treatment of VL.
Resumo:
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.
Resumo:
IntroductionPurpureocillium lilacinum is emerging as a causal agent of hyalohyphomycosis that is refractory to antifungal drugs; however, the pathogenic mechanisms underlying P. lilacinum infection are not understood. In this study, we investigated the interaction of P. lilacinum conidia with human macrophages and dendritic cells in vitro.MethodsSpores of a P. lilacinum clinical isolate were obtained by chill-heat shock. Mononuclear cells were isolated from eight healthy individuals. Monocytes were separated by cold aggregation and differentiated into macrophages by incubation for 7 to 10 days at 37°C or into dendritic cells by the addition of the cytokines human granulocyte-macrophage colony stimulating factor and interleukin-4. Conidial suspension was added to the human cells at 1:1, 2:1, and 5:1 (conidia:cells) ratios for 1h, 6h, and 24h, and the infection was evaluated by Giemsa staining and light microscopy.ResultsAfter 1h interaction, P. lilacinum conidia were internalized by human cells and after 6h contact, some conidia became inflated. After 24h interaction, the conidia produced germ tubes and hyphae, leading to the disruption of macrophage and dendritic cell membranes. The infection rate analyzed after 6h incubation of P. lilacinumconidia with cells at 2:1 and 1:1 ratios was 76.5% and 25.5%, respectively, for macrophages and 54.3% and 19.5%, respectively, for cultured dendritic cells.ConclusionsP. lilacinum conidia are capable of infecting and destroying both macrophages and dendritic cells, clearly demonstrating the ability of this pathogenic fungus to invade human phagocytic cells.
Resumo:
ABSTRACTINTRODUCTION:Hydatidosis is the result of infection with the larval stages of some species of the genus Echinococcus. Treatment approaches for hydatid cysts include the use of albendazole, surgery, and/or medico-surgical procedures. The choice of the therapeutic surgical approach depends on the cyst number and localization, surgeon expertise, and presence of complications. The present study aimed to compare the outcomes of the following therapeutic approaches for the treatment of hepatic hydatid cysts: pericystectomy; the puncture, aspiration, injection, and reaspiration (PAIR) technique; and the PAIR technique followed by deroofing, evacuation of cysts, and omentoplasty.METHODS:The 54 patients were divided into 3 groups: Group I (14 patients) who underwent pericystectomy, Group II (23 patients) who underwent the PAIR technique, and Group III (17 patients) who underwent the PAIR technique followed by deroofing and omentoplasty. The diagnosis of hydatid cysts was based on serological testing using enzyme-linked immunosorbent assay, abdominal ultrasound, and parasitological examination of the cyst contents. Morbidity, mortality, length of hospital stay, recurrence, and postoperative complications were evaluated.RESULTS:Postoperative bleeding, infection, and recurrence were reported in Groups I and II; Group III did not experience postoperative infection and had shorter hospital stays. Recurrence and postoperative complications did not occur in Group III.CONCLUSIONS:The partial surgical procedure with deroofing, evacuation of the cysts, and omentoplasty, as performed in the present study, is recommended as a safe and effective method for elimination of the entire parasite with minimal possibility for intra-peritoneal spillage.
Resumo:
ABSTRACTIn Latin America, Bothrops envenomation is responsible for the majority of accidents caused by venomous snakes. Patients usually present local edema, bleeding and coagulopathy. Visceral hemorrhage is extremely rare and considered a challenge for diagnosis and management. We report the first case of hepatic hematoma owing to the bothropic envenomation in a 66-year-old man who was bitten in the left leg. He presented local edema, coagulopathy, and acute kidney injury. Radiological findings suggested hepatic hematoma, with a volume of almost 3 liters. The hepatic hematoma was gradually absorbed without the need for surgical intervention with complete resolution in 8 months.
Resumo:
Biochemical and hematimetric indicators of inflammation and cell damage were correlated with bilirubin and hepatic and pancreatic enzymes in 30 chronic male alcoholics admitted into psychiatric hospital for detoxification and treatment of alcoholism. Aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, alkaline phosphatase, and total bilirubin were altered, respectively, in 90%, 63%, 87%, 23% and 23% of the cases. None of the indicators of inflammation (lactic dehydrogenase, altered in 16% of the cases; alpha-1 globulin, 24%; alpha-2 globulin, 88%; leucocyte counts, 28%) was correlated with alterations of bilirubin or liver enzymes. Lactic dehydrogenase was poorly sensitive for detection of hepatocytic or muscular damage. Alterations of alpha-globulins seemed to have been due more to alcohol metabolism-induced increase of lipoproteins than to inflammation. Among indicators of cell damage, serum iron, increased in 40% of the cases, seemed to be related to liver damage while creatine phosphokinase, increased in 84% of the cases, related to muscle damage. Hyperamylasemia was found in 20% of the cases and significantly correlated with levels of bilirubin, alkaline phosphatase and gamma-glutamyltransferase. It was indicated that injuries of liver, pancreas, salivary glands, and muscle occurred in asymptomatic or oligosymptomatic chronic alcoholics.
Resumo:
Natural killer cells are increasingly being considered an important component of innate resistance to viruses, but their role in HIV infection is controversial. Some investigators have found that natural killer cells do not confer a protective effect during the progression of HIV disease, whereas others have shown that natural killer cells may be protective and retard the progression of the disease, either through their lytic activity or by a chemokine-related suppression of HIV replication. In this study, we analyzed functional alterations in the activity of natural killer cells during HIV-1 infection using a natural killer cells activity assay with K562 cells as targets. RESULTS: Our results show that the activity of natural killer cells decreases only in the advanced phase of HIV infection and when high (40:1) effector cell-target cell ratios were used. The depression at this stage of the disease may be related to increased levels of some viral factors, such as gp120 or gag, that interfere with the binding capacity of natural killer cells, or to the decreased production of natural killer cells -activity-stimulating cytokines, such as IFN-a and IL-12, by monocytes, a subset of cells that are also affected in the late stage of HIV infection. The data suggest that decreased natural killer cells cell activity may contribute to the severe impairment of the immune system of patients in the late stages of HIV infection.
Resumo:
INTRODUCTION: Traumatic spinal cord injury is one of the most disabling conditions occurring in man and thus stimulates a strong interest in its histopathological, biochemical, and functional changes, primarily as we search for preventive and therapeutic methods. PURPOSE: To develop an experimental model for transplantation of cells from the fetal rat central nervous system to the site of an injured spinal cord of an adult rat in which the transplanted cells survive and become integrated. This experimental model will facilitate investigations of factors that promote regeneration and functional recovery after spinal cord trauma. MATERIAL AND METHODS: Fifteen adult Wistar rats underwent laminectomy, and an spinal cord lesion was made with microdissection. Fetal spinal cord tissue was then transplanted to the site of the injury. The rats were monitored over a 48-hour period, and then their vertebral column was completely removed for histological analysis. RESULTS: In 60% of transplanted rats, the fetal tissue at the injured site remained viable in the site of the lesion.
Resumo:
PURPOSE: To study quantitatively C cells in the thyroids of non-isogenic rats to determine the possible effects of pinealectomy on the number of these cells, and consequently on the synthesis and secretion of calcitonin. METHODS: Twenty male rats of an outbred strain (200-300 g) were used in the present study. One group of 10 animals was pinealectomized 50 days prior to sacrifice. Thyroid tissue was stained for calcitonin (Dako Corporation) at a 1:1500 dilution. The number of C cells observed was expressed as number of cells/cm². Data were analyzed statistically by Mann-Whitney test. RESULTS: The number of C cells in pinealectomized and normal animals ranged from 489 to 2084 per cm² and 227 to 1584 per cm², respectively, a difference that was statistically significant (P <0.05). CONCLUSIONS: These results showed consistent differences in the number of C cells after pinealectomy when compared to controls. We believe that pinealectomy increases the number of C cells in the rat thyroid.
Resumo:
OBJECTIVE: To report a case of bilateral giant renal angiomyolipoma associated with tuberous sclerosis, with successful treatment, and to review the literature concerning angiomyolipoma treatment. CASE REPORT: Patient with tuberous sclerosis and angiomyolipoma diagnosed by ultrasonography during her pregnancy. At that time, the angiomyolipoma on the right side was 9 cm in diameter. Conservative management was selected during her pregnancy. The patient returned 7 years later, with a 24.7 x 19.2 x 10.7 cm tumor on the right side and another of 13 x 11.5 x 6.5 cm on the left side, in addition to multiple small angiomyolipomas. A nephron-sparing surgery with tumoral enucleation was performed on the right side, and after 3 months, the tumor on the left side was removed. Renal function in the post-operative period was preserved, and contrast medium progression was uniform and adequate in both kidneys. CONCLUSION: We conclude that an angiomyolipoma larger than 4 cm should be removed surgically, since they have a greater growth rate and pose a risk of hemorrhage. Resection of smaller tumors is safe and has decreased morbidity. Tumoral enucleation is an effective treatment method that preserves kidney function.