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Peripheral mononuclear cells from more than 160 persons from groups at risk for the acquired immunodeficiency syndrome (AIDS) have yielded AIDS-associated retroviruses (ARV). Antibodies to ARV can also be found in these risk groups. Antibody-negative, virus-positive persons have been identified with early infection or possible viremia with immune complex formation. Established lines of human T and B cells, monocytes, and promyelocytes have been infected with ARV. Moreover, infectious virus has been recovered from macrophages cultured from the blood of some persons with AIDS. The cytopathic effects of ARV in T cells is associated with the accumulation of unintegrated viral forms in the infected cells. The ARV has also been isolated from plasma, serum, saliva, semen, urine, cerebrospinal fluid, and brain tissue. All these results reflect the wide host range of ARV and support its role in neurologic abnormalities seen in some patients. Molecular studies of independent ARV isolates indicate a polymorphism of nucleotide sequences, particularly in the viral envelope region. All these features place ARV in the lentivirus subfamily of human retroviruses.  相似文献   
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We reviewed 428 subjects with colorectal serrated lesions resected endoscopically or surgically at our institution. Colorectal serrated lesions were pathologically divided into 3 groups: hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA). SSA/P was detected frequently in the right colon and SSA/P was mainly flat-elevated. Cancers occurring in SSA/P were found more frequently than HP or TSA. The incidence of cancer in SSA/P was equivalent to that of cancer in traditional adenoma. Further studies are warranted to clarify clinicopathological features of serrated lesions of the colorectum.  相似文献   
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The use of gamma-radiation in treatment of pelvic cancer is associated with injury of healthy surrounding tissues and disorders of intestinal motility; however, the cellular mechanisms involved are unclear. We tested the hypothesis that exposure of visceral smooth muscle cells (SMCs) to gamma-radiation induces apoptosis via activation of specific protein kinase C (PKC) isoforms. Cultured SMCs and slices from guinea pig ileum smooth muscle longitudinal layer (GPISMLL) were exposed to 10 to 50 Gy. Flow cytometry in gamma-radiated SMCs showed increased percentage of cells in the sub-G(0)/G(1) phase, a hallmark of apoptosis. gamma-Radiation-induced reduction in cell survival was partially but significantly alleviated with the PKC inhibitors. Sections of gamma-irradiated GPISMLL showed DNA fragmentation and apoptotic bodies analyzed by the terminal deoxynucleotidyl transferase dUTP nick-end labeling method, whereas the plasma and nuclear membranes were preserved. Confocal microscopy in gamma-radiated SMCs labeled with annexin V-fluorescein showed an increase in apoptotic cells and phosphatidylserine externalization. Contraction of GPISMLL strips in response to KCl and acetylcholine was reduced in tissues exposed to 30 and 50 Gy. gamma-Radiation of GPISMLL caused an increase in PKC activity in the particulate fraction, a decrease in the cytosolic fraction, and increased particulate/cytosolic PKC activity ratio. Western blot analysis revealed significant amounts of alpha- and epsilon-PKC in the cytosolic fraction of control GPISMLL. gamma-Radiation caused an increase in the amount of alpha- and epsilon-PKC in the particulate fraction and a decrease in the cytosolic fraction. Data suggest that gamma-radiation induces apoptosis, growth arrest, and contractile dysfunction in visceral SMCs of GPISMLL via activation and translocation of alpha- and epsilon-PKC isoforms.  相似文献   
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This paper reports the isolation of St. Louis encephalitis virus (SLEV) from a febrile human case suspected to be dengue, in S?o Pedro, S?o Paulo State. A MAC-ELISA done on the patient's acute and convalescent sera was inconclusive and hemagglutination inhibition test detected IgG antibody for flaviviruses. An indirect immunofluorescent assay done on the C6/36 cell culture inoculated with the acute serum was positive for flaviviruses but negative when tested with dengue monoclonal antibodies. RNA extracted from the infected cell culture supernatant was amplified by RT-PCR in the presence of NS5 universal flavivirus primers and directly sequenced. Results of BLAST search indicated that this sequence shares 93% nucleotide similarity with the sequence of SLEV (strain-MSI.7), confirmed by RT-PCR performed with SLEV specific primers. Since SLEV was identified as the cause of human disease, it is necessary to improve surveillance in order to achieve early detection of this agent in the state of S?o Paulo and in Brazil. This finding is also an alert to health professionals about the need for more complete clinical and epidemiological investigations of febrile illnesses as in the reported case. SLEV infections can be unrecognized or confused with other ones caused by an arbovirus, such as dengue.  相似文献   
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The aim of this report is to present the preliminary results of a Phase II study of high-dose (74 Gy RBE) proton beam therapy (PBT) with concurrent chemotherapy for unresectable locally advanced non-small-cell lung cancer (NSCLC). Patients were treated with PBT and chemotherapy with monthly cisplatin (on Day 1) and vinorelbine (on Days 1 and 8). The treatment doses were 74 Gy RBE for the primary site and 66 Gy RBE for the lymph nodes without elective lymph nodes. Adapted planning was made during the treatment. A total of 15 patients with Stage III NSCLC (IIIA: 4, IIIB: 11) were evaluated in this study. The median follow-up period was 21.7 months. None of the patients experienced Grade 4 or 5 non-hematologic toxicities. Acute pneumonitis was observed in three patients (Grade 1 in one, and Grade 3 in two), but Grade 3 pneumonitis was considered to be non-proton-related. Grade 3 acute esophagitis and dermatitis were observed in one and two patients, respectively. Severe ( ≥ Grade 3) leukocytopenia, neutropenia and thrombocytopenia were observed in 10 patients, seven patients and one patient, respectively. Late radiation Grades 2 and 3 pneumonitis was observed in one patient each. Six patients (40%) experienced local recurrence at the primary site and were treated with 74 Gy RBE. Disease progression was observed in 11 patients. The mean survival time was 26.7 months. We concluded that high-dose PBT with concurrent chemotherapy is safe to use in the treatment of unresectable Stage III NSCLC.  相似文献   
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