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41.
MEETING NOTES: The Lustgarten Foundation for Pancreatic Cancer Research 3rd Annual Scientific Conference: "Pancreatic Cancer: From Genes to Treatment"  相似文献   
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Florianópolis, a city located in the Santa Catarina State in southern Brazil, is the national leading producer of bivalve mollusks. The quality of bivalve mollusks is closely related to the sanitary conditions of surrounding waters where they are cultivated. Presently, cultivation areas receive large amounts of effluents derived mainly from treated and non-treated domestic, rural, and urban sewage. This contributes to the contamination of mollusks with trace metals, pesticides, other organic compounds, and human pathogens such as viruses, bacteria, and protozoan. The aim of this study was to perform a thorough diagnosis of the shellfish growing areas in Florianópolis, on the coast of Santa Catarina. The contamination levels of seawater, sediments, and oysters were evaluated for their microbiological, biochemical, and chemical parameters at five sea sites in Florianópolis, namely three regular oyster cultivation areas (Sites 1, 2, and oyster supplier), a polluted site (Site 3), and a heavily polluted site (Site 4). Samples were evaluated at day zero and after 14 days. Seawater and sediment samples were collected just once, at the end of the experiment. Antioxidant defenses, which may occur in contaminated environments in response to the increased production of reactive oxygen species (ROS) by organisms, were analyzed in oysters, as well as organic compounds (in oysters and sediment samples) and microbiological contamination (in oysters and seawater samples). The results showed the presence of the following contaminants: fecal coliforms in seawater samples (four sites), human adenovirus (all sites), human noroviruses GI and GII (two sites), Hepatitis A viruses (one site), JC Polyomavirus in an oyster sample from the oyster supplier, Giardia duodenalis cysts, and Cryptosporidium sp oocysts (one site). Among organochlorine pesticides, only DDT (dichlorodiphenyltrichloroethane) and HCH (hexachlorocyclohexane) were detected in some sediment and oysters samples in very low levels; site 4 had the highest concentrations of total aliphatic hydrocarbons, PAHs, and linear alkylbenzenes (LABs) found either in oysters or in sediment samples. The major concentration of fecal sterol coprostanol was found at site 4, followed by site 3. After 14 days of allocation in the four selected sites, there was a significant difference in the enzymes analyzed at the monitored spots. The detection of different contaminants in oysters, seawater, and sediment samples in the present study shows the impact untreated or inadequately treated effluents have on coastal areas. These results highlight the need for public investment in adequate wastewater treatment and adequate treatment of oysters, ensuring safe areas for shellfish production as well as healthier bivalve mollusks for consumption.  相似文献   
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We report a patient with a disease characterized by proliferation of T cells with Fc receptors for IgG (TG). However, unlike lymphoid cells from normal individuals or from patients with other lymphoid malignancies, the patient's lymphocytes spontaneously produced gamma interferon (IFN-gamma) in vitro. The peripheral lymphocytes consisted of 95% TG cells, which exhibited the morphological characteristics of T- cell chronic lymphocytic leukemia (CLL) and were normal on cytochemical and chromosome analysis. The majority of TG cells were OKT3+, OKT8+, and OKT4-, 3A1-. These cells failed to express suppressor cell activity and displayed depressed levels of natural killer activity, but mediated antibody-dependent cell-mediated cytotoxicity. The spontaneous production of IFN-gamma by human peripheral lymphoid cells as demonstrated in this study may serve as a probe for studying the relationship between IFN-gamma and the proliferation of human T-cell subsets.  相似文献   
46.
Odom  LF; Gordon  EM 《Blood》1984,64(4):875-882
Four of five infants and young children with acute monoblastic leukemia, a disease that heretofore has been highly refractory to therapy, were successfully treated with sequential infusions of a podophyllin derivative employed as a single agent over a protracted period of time. In three of the five children, monocytic leukemia cutis was present at birth. Treatment was begun in two of them when the disease had progressed to systemic involvement at a few months of age, and in the third when disease was still localized. The other two children were 11 and 18 months of age at initial presentation with widespread disease. Four children are off therapy 11 months, 26 months, 5 years, and 6 years, respectively.  相似文献   
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OBJECTIVES: To evaluate if the immunofluorescence analysis of synovial tissue (ST) using antibodies against RANKL/OPG, conjugated with the immunophenotyping of lymphocytes and macrophages, could be of diagnostic and prognostic value in rheumatoid arthritis (RA) patients. METHODS: 3-year prospective study of 103 consecutive patients submitted to closed needle biopsy for diagnostic purposes. ST was analyzed with routine histologic techniques and immunofluorescence, using monoclonal antibodies against RANKL, OPG, CD163, CD68, CD4, CD8, interferon-gamma and CD19. Patients were prospectively evaluated with a clinical, laboratorial and radiological protocol. At the end of the follow-up patients were divided according to the final diagnosis. Results of the initial histologic evaluation were compared between the main diagnostic groups and in RA patients histologic data was correlated with clinical and radiologic outcome measures. RESULTS: The RANKL/OPG ratio and the inflammatory infiltrate were significatively higher in RA (n = 25) as compared to the same ratio observed in other inflammatory joint diseases (OIJD, n = 48) and in osteoarthritis (n = 17). The difference between RA and OIJD was specifically confirmed when the comparison involved spondyloarthropathy (n = 26). Final HAQ score and radiologic outcome were correlated with the density of intimal CD68+ macrophages. Radiologic progression was correlated with subintimal CD4+ lymphocytes and CD68+ macrophages and intimal CD68 and CD163+ macrophages. CONCLUSION: The quantification of the RANKL/OPG ratio and of the number of lymphocytes in the ST might be useful to differentiate RA from other inflammatory joint diseases. The ST number of CD4+ lymphocytes and macrophages are probable predictors of radiologic progression in RA patients.  相似文献   
49.
Quelle  FW; Caslake  LF; Burkert  RE; Wojchowski  DM 《Blood》1989,74(2):652-657
Conditions presently have been established for the high-level expression and simplified purification of recombinant human erythropoietin produced in Spodoptera frugiperda cells. Expression, as mediated by infection with a recombinant baculovirus, was accomplished in suspension culture using reduced levels of serum and media supplements experimentally determined to provide optimum levels of factor production (500,000 U/L). Purification of this recombinant human erythropoietin to virtual homogeneity (greater than or equal to 99%) was accomplished via a simple three-step procedure involving isocratic elution from DEAE-Sephacel, reverse-phase high performance liquid chromatography (HPLC) on a C4 medium, and the single-step elution of purified hormone from concanavalin A agarose. Overall, an 890-fold purification was accomplished with a recovery of 80% as assayed in vitro. Biologically, this purified erythropoietin is highly active, possessing a specific activity in vitro of 200,000 U/mg protein. Chemically, this erythropoietin (molecular weight [mol wt] 26,200) appears exceptionally uniform in its oligosaccharide constitution (30%) as contrasted with heterogeneously glycosylated erythropoietins derived from mammalian cells (mol wt 30,000 to 38,000; 40% to 50% complex-type oligosaccharide). Thus, human erythropoietin as presently produced in an insect cell line comprises not only an abundant source of highly active, readily purified hormone for studies of its mechanism of action and cell surface receptor, but also represents a uniquely homogeneous form that should prove advantageous for direct structural analyses.  相似文献   
50.
Left ventricular noncompaction (LVNC) is a congenital pathology that directly affects the lining walls of myocardial tissue, causing trabeculations with blood filling in the inner wall of the heart, concomitantly with the development of a mesocardial thinning. Although LVNC was described for the first time as long ago as 1984, our understanding of the disease with regard to its genetic pattern, diagnosis, clinical presentation and treatment is still scanty. LVNC can present as an isolated condition or associated with congenital heart disease, genetic syndromes or neuromuscular disease. This suggests that LVNC is not a distinct form of cardiomyopathy, but rather a morphological expression of different diseases. Recognition of the disease is of fundamental importance because its clinical manifestations are variable, ranging from the absence of any symptom to congestive heart failure, lethal arrhythmias and thromboembolic events. The study of this disease has emphasized its genetic aspects, as it may be of sporadic origin or hereditary, in which case it most commonly has an autosomal dominant inheritance or one linked to the X chromosome. Echocardiography is the gold standard for diagnosis, and magnetic resonance imaging may refine the identification of the disease, especially in those patients with non-conclusive echocardiography. This article sets out to review the main characteristics of LVNC and present updates, especially in the genetic pattern, diagnosis and treatment of the disease.  相似文献   
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