80 research outputs found
Purification and characterization of a collagenase from Penicillium sp. UCP 1286 by polyethylene glycol-phosphate aqueous two-phase system
Collagenases are proteolytic enzymes capable of degrading both native and denatured collagen, reported to be applied in industrial, medical and biotechnological sectors. Liquid-liquid extraction using aqueous two-phase system (ATPS) is one of the most promising bioseparation techniques, which can substitute difficult solid-liquid separation processes, offering many advantages over conventional methods including low-processing time, low-cost material and low-energy consumption. The collagenase produced by Penicillium sp. UCP 1286 showed a stronger affinity for the bottom salt-rich phase, where the highest levels of collagenolytic activity were observed at the center point runs, using 15.0% (w/w) PEG 3350 g/mol and 12.5% (w/w) phosphate salt at pH 7.0 and concentration. The enzyme was characterized by thermal stability, pH tolerance and effect of inhibitors, showing optimal collagenolytic activity at 37 °C and pH 9.0 and proved to be a serine protease. ATPS showed high efficiency in the collagenase purification, confirmed by a single band in SDS/PAGE, and can in fact be applied as a quick and inexpensive alternative method.This work was supported by the National Council of Technological and Scientific Development (CNPq) and Coordination for the Improvement of Higher Education Personnel (CAPES). Sara Silvério also acknowledges her post-doc grant (SFRH/BPD/88584/2012) from FCT (SFRH/BPD/88584/2012) (Portuguese Science and Technology Foundation), Portugal
Production and characterization of collagenase by Penicillium sp. UCP 1286 isolated from Caatinga soil
A new Penicillium sp. strain isolated from the soil of Caatinga, a Brazilian Biome (UCP 1286) was selected for collagenase production. Fermentation system allowing obtention of collagenolytic activity about 2.7 times higher than existing data, with the highest values of collagenolytic and specific activity (379.80 U/mL, 1460.77 U/mg, respectively), after 126 hours. Applying a factorial design, enzyme production was increased by about 65% compared to the preliminary results. The factorial design demonstrated the existence of two factors with statistical significance on the production of the enzyme: pH and temperature, both with negative effects. Enzyme was found to be more active at pH 9.0 and 37 °C, and also to be very stable in comparison with the collagenase produced by other microorganisms. The enzyme seems to belong to collagenolytic serine proteases family. Concerning the substrate specificity, it was observed that the highest enzyme activity corresponds to azocoll, there was no relevant activity on azocasein and the enzyme showed to be more specific to type V collagen and gelatin than the commercial colagenase produced by Clostridium histolyticum. Major band observed at electrophoresis was approximately 37 kDa. Zymogram analysis confirmed the collagenolytic activity. All data indicates this enzyme as promising biotechnology product.This work was supported by Fundação de Amparo Ă CiĂȘncia e Tecnologia do Estado de Pernambuco (FACEPE) (IBPG-0137-2.08/12) and Conselho Nacional de Desenvolvimento CientĂfico e TecnolĂłgico (CNPq). Sara SilvĂ©rio also acknowledges her post-doc grant (SFRH/BPD/88584/2012) from FCT (Fundação para a CiĂȘncia e a Tecnologia), Portugal
Clinical and pathological evaluation of fibrolamellar hepatocellular carcinoma: a single center study of 21 cases
OBJECTIVES: Fibrolamellar hepatocellular carcinoma is a rare primary malignant liver tumor that differs from conventional hepatocellular carcinoma in several aspects. The aim of this study was to describe the clinical, surgical and histopathological features of fibrolamellar hepatocellular carcinoma and to analyze the factors associated with survival. METHODS: We identified 21 patients with histopathologically diagnosed fibrolamellar hepatocellular carcinoma over a 22-year period. Clinical information was collected from medical records and biopsies, and surgical specimens were reviewed. RESULTS: The median age at diagnosis was 20 years. Most patients were female (67%) and did not have associated chronic liver disease. Most patients had a single nodule, and the median tumor size was 120 mm. Vascular invasion was present in 31% of patients, and extra-hepatic metastases were present in 53%. Fourteen patients underwent surgery as the first-line therapy, three received chemotherapy, and four received palliative care. Eighteen patients had âpure fibrolamellar hepatocellular carcinoma,â whereas three had a distinct area of conventional hepatocellular carcinoma and were classified as having âmixed fibrolamellar hepatocellular carcinoma.â The median overall survival was 36 months. The presence of âmixed fibrolamellar hepatocellular carcinomaâ and macrovascular invasion were predictors of poor survival. Vascular invasion was associated with an increased risk of recurrence in patients who underwent surgery. CONCLUSION: Fibrolamellar hepatocellular carcinoma was more common in young female patients without chronic liver disease. Surgery was the first therapeutic option to achieve disease control, even in advanced cases. Vascular invasion was a risk factor for tumor recurrence. The presence of macrovascular invasion and areas of conventional hepatocellular carcinoma were directly related to poor survival
Low prevalence of renal, cardiac, pulmonary, and neurological extra-articular clinical manifestations in spondyloarthritis: analysis of the Brazilian Registry of Spondyloarthritis
OBJECTIVE: To describe the extra-articular manifestations (cardiac, renal, pulmonary, and neurological), usually not related to spondyloarthritis (SpA), in a large cohort of Brazilian patients. MATERIALS AND METHODS: This retrospective study analyzed 1,472 patients diagnosed with SpA and cared for at 29 health care centers distributed in the five major geographic regions in the country, participating in the Brazilian Registry of Spondyloarthritis (BRS). All patients were assessed for the prevalence of major extra-articular manifestations (cardiac, renal, pulmonary, and neurological), classified according to the diagnosis [ankylosing spondylitis (AS), psoriatic arthritis (PsA), reactive arthritis (ReA), arthritis associated with inflammatory bowel disease (IBD), undifferentiated spondyloarthritis (uSpA), and juvenile SpA], and according to the clinical presentation (axial, peripheral, mixed, and enthesitis). RESULTS: Of the patients with SpA assessed, 963 had AS, 271 PsA, 49 ReA, 48 arthritis associated with IBD, 98 uSpA, and 43 juvenile SpA. Cardiac involvement was reported in 44 patients (3.0%), pulmonary involvement in 19 (1.3%), renal involvement in 17 (1.2%), and neurological involvement in 13 patients (0.9%). Most patients with visceral involvement had AS or PsA, and the mixed (axial + peripheral) and/or predominantly axial clinical form. CONCLUSION: Cardiac, renal, pulmonary, and neurological extra-articular manifestations are quite infrequent in SpA, ranging from 0.9% to 3% in this large Brazilian cohort, and affected predominantly patients with AS and PsA.OBJETIVO: Descrever as manifestaçÔes extra-articulares (cardĂacas, renais, pulmonares e neurolĂłgicas) geralmente nĂŁo relacionadas Ă s espondiloartrites (EpA) em uma grande coorte de pacientes brasileiros. MĂTODOS: Este estudo retrospectivo analisou 1.472 pacientes com o diagnĂłstico de EpA atendidos em 29 centros distribuĂdos pelas cinco principais regiĂ”es geogrĂĄficas do Brasil, integrantes do Registro Brasileiro de Espondiloartrites. Todos os pacientes foram avaliados para a prevalĂȘncia das principais manifestaçÔes extra-articulares (cardĂacas, renais, pulmonares e neurolĂłgicas), divididas por diagnĂłstico [espondilite anquilosante (EA), artrite psoriĂĄsica (AP), artrite reativa (ARe), artrite associada a doença inflamatĂłria intestinal (DII), EpA indiferenciada (EI) e EpA juvenil] e por forma clĂnica (axial, perifĂ©rica, mista e entesĂtica). RESULTADOS: Dentre os pacientes avaliados com EpA, 963 apresentavam EA, 271 AP, 49 ARe, 48 artrite associada a DII, 98 EI e 43 EpA juvenil. Acometimento cardĂaco foi observado em 44 pacientes (3,0%), seguido por acometimento pulmonar em 19 (1,3%), renal em 17 (1,2%) e neurolĂłgico em 13 pacientes (0,9%). A maioria dos casos de acometimento visceral ocorreu nos pacientes com EA ou AP e naqueles com forma clĂnica mista (axial e perifĂ©rica) e/ou predominantemente axial. CONCLUSĂO: As manifestaçÔes extra-articulares cardĂacas, renais, pulmonares e neurolĂłgicas sĂŁo muito pouco frequentes nas EpA, variando de 0,9%-3% nesta grande coorte brasileira, estando mais associadas a EA e AP.37938
Controversial issues in the management of hyperprolactinemia and prolactinomas : an overview by the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism
Prolactinomas are the most common pituitary adenomas (approximately 40% of cases), and they represent an important cause of hypogonadism and infertility in both sexes. The magnitude of prolactin (PRL) elevation can be useful in determining the etiology of hyperprolactinemia. Indeed, PRL levels > 250 ng/mL are highly suggestive of the presence of a prolactinoma. In contrast, most patients with stalk dysfunction, drug-induced hyperprolactinemia or systemic diseases present with PRL levels < 100 ng/mL. However, exceptions to these rules are not rare. On the other hand, among patients with macroprolactinomas (MACs), artificially low PRL levels may result from the so-called âhook effectâ. Patients harboring cystic MACs may also present with a mild PRL elevation. The screening for macroprolactin is mostly indicated for asymptomatic patients and those with apparent idiopathic hyperprolactinemia. Dopamine agonists (DAs) are the treatment of choice for prolactinomas, particularly cabergoline, which is more effective and better tolerated than bromocriptine. After 2 years of successful treatment, DA withdrawal should be considered in all cases of microprolactinomas and in selected cases of MACs. In this publication, the goal of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism (SBEM) is to provide a review of the diagnosis and treatment of hyperprolactinemia and prolactinomas, emphasizing controversial issues regarding these topics. This review is based on data published in the literature and the authors' experience
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