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Background  

Leishmaniases are among the most proteiform parasitic infections in humans ranging from unapparent to cutaneous, mucocutaneous or visceral diseases. The various clinical issues depend on complex and still poorly understood mechanisms where both host and parasite factors are interacting. Among the candidate factors of parasite virulence are the A2 genes, a family of multiple genes that are developmentally expressed in species of the Leishmania donovani group responsible for visceral diseases (VL). By contrast, in L. major determining cutaneous infections (CL) we showed that A2 genes are present in a truncated form only. Furthermore, the A2 genomic sequences of L. major were considered subsequently to represent non-expressed pseudogenes [1]. Consequently, it was suggested that the structural and functional properties of A2 genes could play a role in the differential tropism of CL and VL leishmanias. On this basis, it was of importance to determine whether the observed structural/functional particularities of the L. major A2 genes were shared by other CL Leishmania, therefore representing a proper characteristic of CL A2 genes as opposed to those of VL isolates.  相似文献   
94.
Push enteroscopy in the investigation of small-intestinal disease   总被引:3,自引:0,他引:3  
We report our experience with small-bowel push enteroscopy in 50 patients. The indications for push enteroscopy were: anaemia/occult gastrointestinal bleeding (22 patients); overt gastrointestinal bleeding (17 patients); abnormal small-bowel radiology (8 patients) and miscellaneous (3 patients). In those with undiagnosed gastrointestinal bleeding/anaemia, abnormalities were detected in 24/39 patients (62%): small bowel arteriovenous malformations (AVMs) were detected in 19 (49%), and five (13%) had lesions in the upper gastrointestinal tract. Seventeen patients had heater-probe ablation therapy of vascular lesions: nine patients had small-intestinal lesions, four patients gastric lesions, and four patients combined gastric and small- intestinal lesions. In those with abnormal small-bowel radiology, abnormalities were detected in 6/8 patients. We conclude that (i) push enteroscopy can establish a diagnosis in a high proportion of patients with gastrointestinal bleeding; (ii) heater-probe ablation therapy of vascular lesions can be performed routinely at the time of enteroscopy; (iii) a significant proportion of patients (9/50) referred for enteroscopy with undiagnosed gastrointestinal bleeding have lesions in the stomach/proximal duodenum missed at diagnostic endoscopy. Push enteroscopy is a valuable diagnostic and therapeutic endoscopic procedure.   相似文献   
95.
Summary— Neuropeptide gamma (NPγ) induced a contractile response of the human isolated bronchus which was potentiated by the neutral endopeptidase inhibitor, phosphoramidon, but was not modified by atropine and indomethacin. NPγ was 3.31-fold more potent than NKA. Contractile response curves to NPγ were shifted to the right and maximal responses reduced by the non-peptide NK2-receptor antagonist, SR 48968. The pKB of SR 48968 (8.94 ± 0.18, n = 15), calculated according to Kenakin (1987) was very close to that reported for [Nle10]-NKA (4–10), a specific agonist of neurokinin NK2-receptors (8.86 ± 0.13, n = 13), suggesting that the contractile effects of NPγ on the human isolated bronchus were mediated through NK2A-receptors.  相似文献   
96.
Malignant lymphoma particularly of T phenotype can be associated with specific or non specific cutaneous lesions. These cutaneous manifestations can occur at the onset of the disease being sometimes the revealing sign or they can appear during the course of the lymphoreticular malignancies. Glomerulonephritis was also described in lymphoma. Ki- positive large cell lymphoma was recently identified. A new case is reported with lymphadenopathy and intestinal localisation revealed by cutaneous and mucosal ulcerations principally in the mouth and a focal segmental glomerulonephritis with endo- and extracapillary proliferation. The absence of lymphoma in cutaneous and renal lesions and the clinical presentation support the hypothesis of paraneoplastic manifestations, may be related to a vasculitis.  相似文献   
97.
In 990, Anhalt et al described a newly autoimmune billious disease: paraneoplastic pemphigus, in five patients. It was characterized by a distinct set of circulating autoantibodies from those in the sera of patients with pemphigus vulgaris and superficial pemphigus. We report a 7 year-old man with chronic lymphocytic leukemia of years duration who developed a severe mucocutaneous eruption with clinical and immunofluorescence findings of pemphigus vulgaris evolving into an oral bullous lichen planus presentation. Evaluation of his serum confirmed the presence of autoantibodies specific for paraneoplastic pemphigus by indirect immunofluorescence on rat-bladder and immunoprécipitation. Subsequently, additional cases have been reported in the literature. All occured in patients with various neoplastic conditions. These patients present with polymorphous skin lesions and severe erosive oral disease. Histologic examination shows interface dermatitis and keratinocyte necrosis in addition to acantolysis. Direct immunofluorescence may reveal deposition of immunoglobulin and/or complement at the basement membrane as well as deposition on epithelial cell surfaces. Circulating IgG anti-cell-surface antibodies are detectable with both stratified and stratified epithelia as substrates. These antibodies immunoprecipitate a complex of four desmosomal proteins, including desmoplakin I (50 kDa), the bullous pemphigoid antigen (0 kDa), desmoplakin II (0 kDa) and a 90 kDa antigen.  相似文献   
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99.
In an attempt to decrease the relapse rate after bone marrow transplantation (BMT) for advanced acute leukemia, we initiated studies using 131I-labeled anti-CD45 antibody (BC8) to deliver radiation specifically to hematopoietic tissues, followed by a standard transplant preparative regimen. Biodistribution studies were performed in 23 patients using 0.5 mg/kg trace 131I-labeled BC8 antibody. The BC8 antibody was cleared rapidly from plasma with an initial disappearance half-time of 1.5 +/- 0.2 hours, presumably reflecting rapid antigen- specific binding. The mean radiation absorbed doses (cGy/mCi131I administered) were as follows: marrow, 7.1 +/- 0.8; spleen, 10.8 +/- 1.4; liver, 2.7 +/- 0.2; lungs, 2.1 +/- 0.1; kidneys, 0.7 +/- 0.1; and total body, 0.4 +/- 0.03. Patients with acute myelogenous leukemia (AML) in relapse had a higher marrow dose (11.4 cGy/mCi) than those in remission (5.2 cGy/mCi; P = .001) because of higher uptake and longer retention of radionuclide in marrow. Twenty patients were treated with a dose of 131I estimated to deliver 3.5 Gy (level 1) to 7 Gy (level 3) to liver, with marrow doses of 4 to 30 Gy and spleen doses of 7 to 60 Gy, followed by 120 mg/kg cyclophosphamide (CY) and 12 Gy total body irradiation (TBI). Nine of 13 patients with AML or refractory anemia with excess blasts (RAEB) and two of seven with acute lymphocytic leukemia (ALL) are alive disease-free at 8 to 41 months (median, 17 months) after BMT. Toxicity has not been measurably greater than that of CY/TBI alone, and the maximum tolerated dose has not been reached. This study demonstrates that with the use of 131I-BC8 substantially greater doses of radiation can be delivered to hematopoietic tissues as compared with liver, lung, or kidney, which may improve the efficacy of marrow transplantation.  相似文献   
100.
Because interleukin-10 (IL-10) is a potent differentiation factor of human B cells into mature plasma cells, we investigated its effect on human malignant plasma cells. IL-10 did not induce any differentiation and increase in Ig synthesis in four human IL-6-dependent malignant plasma cell lines. However, it stimulated the proliferation of two of four cytokine-dependent cell lines in the absence of IL-6 and IL-10- dependent myeloma cell lines have been obtained. The myeloma cell growth activity of IL-10 was unaffected by anti-IL-6 and anti-IL-6R antibodies. Similarly, IL-10 stimulated (P = .001) the proliferation of freshly-explanted myeloma cells in IL-6-deprived cultures of tumor samples from patients with active multiple myeloma (MM) and produced twice as many myeloma cells in these cultures. Again, this cytokine was unable to induce further differentiation (assessed by rate of Ig production) of fresh myeloma cells. A very sensitive enzyme-linked immunosorbent assay (ELISA; 1 pg/mL) only rarely detected IL-10 in the sera of MM patients (3 of 89). On the contrary, serum IL-10 was detected in 60% of patients with plasma cell leukemia (12 of 20). These data show that IL-10 is an IL-6-unrelated growth factor for malignant plasmablastic cells. This cytokine could be involved in the late phase of MM in vivo.  相似文献   
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