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931.
C Siepl S Bodmer K Frei H R MacDonald R De Martin E Hofer A Fontana 《European journal of immunology》1988,18(4):593-600
Human glioblastoma cells secrete a peptide termed glioblastoma-derived T cell suppressor factor (G-TsF) which inhibits T cell activation. Recently, purification and cloning of G-TsF revealed that G-TsF is identical to transforming growth factor-beta 2. As shown here, G-TsF suppresses the growth of an ovalbumin-specific mouse T helper cell clone (OVA-7T) independently of the stimulus used being either (a) antigen in the presence of antigen-presenting cells, or (b) interleukin 2 (IL2) or (c) phorbol ester and calcium ionophore. Furthermore, in the presence of antibodies against IL2 receptors, G-TsF was able to suppress the residual proliferation still observed when OVA-7T were stimulated with phorbol ester/ionophore. G-TsF failed to inhibit the release of IL3 from OVA-7T activated with IL2. Taken together, the data provide evidence that G-TsF does not directly interfere with interactions of IL2 with its receptor but rather inhibits T cell activation by interfering with an as yet unidentified pathway used by both IL2 and phorbol ester/ionophore. When analyzing different monokines and lymphokines for its effect on G-TsF-induced suppression of T cell growth the only factor found to partially neutralize the effect of G-TsF was tumor necrosis factor-alpha. 相似文献
932.
Antonia D'Errico Walter F. Grigioni Michelangelo Fiorentino Paola Baccarinl Eugene Lamas Stella De Mitri Giuseppe Gozzetti Antonio M. Mancini Christian Brechot 《Pathology international》1994,44(2):131-137
Recent results obtained using molecular biology techniques have suggested a possible role for insulin-like growth factor II (IGF-II) in the pathogenesis of hepatocellular carcinoma (HCC). To investigate this phenomenon, a monoclonal anti-body was used against IGF-II to study 54 patients with HCC. The presence of HBsAg was also tested both in serum and liver tissue. A positive immunoreaction was found in 9/15 (60%) of the HCC arising in cirrhotic livers of patients who had serum markers for HBV (HBV+ positive patients). These results provide further evidence that HBV might play a role in the expression of IGF-II. In HCC of patients without any markers of HBV infection (HBV- negative patients), IGF–II was detected in 10/39 (25.6%) of the tumors, and in some benign neoplastic lesions. It was found not only in neoplastic cells but also in some dysplastic nodules. The speculation arises that IGF–II expression may play a role in some steps of hepato-carcinogenesis. 相似文献
933.
R. B. Bajnath N. van den Berghe H. R. De Jonge J. A. Groot 《Pflügers Archiv : European journal of physiology》1993,425(1-2):90-99
The differentiated clone 19A of the HT-29 human colon carcinoma cell line was used as a model to study the intracellular electrophysiological effects of interaction of the cAMP, the protein kinase C (PKC) and the Ca2+ pathways, (a) A synergistic effect between ionomycin and forskolin was observed. From intracellular responses it was concluded that the synergistic effect is caused by activation of an apical Cl– conductance by protein kinase A and a basolateral K+ conductance by Ca2+. (b) A transient synergistic effect of ionomycin and the phorbol ester phorbol dibutyrate (PDB) was found. The decrease of the response appeared to be due to PKC-dependent inactivation of the basolateral K+ conductance. The synergism is caused by PKC-dependent increase of the apical Cl– conductance and Ca2+-dependent increase of the basolateral K+ conductance. (c) The effects of carbachol and PDB were not fully additive presumably because of their convergence on PKC activation, (d) Forskolin and PDB, when added in this order, had a less than additive effect. Results of cell-attached patch-clamp studies, presented in the accompanying paper, showed a synergistic effect of forskolin and PDB on non-rectifying small-conductance Cl– channels. Assuming that these channels are involved in the transepithelial responses it is suggested that forskolin and PDB induce a modulatory, synergistic increase of the apical Cl– conductance when both pathways are activated simultaneously. (e) The HT-29cl.19A cells differ from T84 cells in that the latter did not respond with an increase of the short-circuit current to addition of phorbol ester. This may be due to a very low expression of PKC. 相似文献
934.
B D Cheson C C De Bellis G B Schumann J L Schumann 《American journal of clinical pathology》1985,83(4):421-425
The authors examined urine specimens from 30 patients with multiple myeloma (MM) to determine the usefulness of cytodiagnostic urinalysis in evaluating such patients. Nine patients had clinical evidence of renal failure. In six of these nine patients (67%), or 20% of all patients, the urine sediment contained unique "MM-casts." These were characterized by a waxy to granular matrix surrounded by reactive, syncytial, giant cells with occasional renal cells embedded in the cast matrix. These casts were not observed in urine specimens from patients with normal renal function. Renal biopsy in two patients with MM-casts confirmed that cytologic diagnosis of "MM-kidney." The patient groups with or without MM-casts were comparable with respect to age, sex, and clinical stage of disease. In contrast, those with MM-casts were more likely to have clinical evidence of renal disease (100% vs. 13%), Bence Jones proteinuria (100% vs. 35%), hypercalcemia (50% vs. 8%), and hyperuricemia (50% vs. 4%). The two groups could not be distinguished reliably by urine physicochemical determinations. However, there were marked differences in the frequency of microscopic abnormalities. All patients with MM-cast formation excreted other pathologic casts as well and had evidence of tubular injury, while five of six had evidence of ischemic necrosis. This compared with 17%, 13%, and 21%, respectively, of those without MM-casts. Thus, cytodiagnostic urinalysis is of value in distinguishing MM-kidney from the numerous other causes of renal failure in patients with MM. 相似文献
935.
M. De Marchi A. O. CARBONARA F. Carozzi F. Massara L. Belforte G. M. Moldsatti D. Bisbocci M. P. Passarino G. Palestro 《Clinical genetics》1976,10(5):265-272
A case of true hermaphroditism with 46, XX/46, XY karyotype is reported. The propositus, reared as a male, showed ambiguous external genitalia with perineoscrotal hypospadias, and internal genitalia represented by bilateral ovotestes, normal uterus and tubes. Periodic menstrual bleedings appeared at puberty. The endocrinologic data demonstrated the secretory activity of both the ovarian and the testicular tissue. The analysis of red cell, lymphocyte and serum markers, done on the propositus and on his parents, failed to show any evidence of double fertilization. On this basis, the origin of the XX/XY condition (mosaicism versus chimerism) and its developmental consequences are discussed. 相似文献
936.
Alvarez M García F Martínez NM Hernández Quero J Louwagie J De Brauwer A Maroto MC 《Journal of medical virology》2004,73(2):151-157
The changes in viral load and CD4(+) count at 3 and 6 months in a group of 166 HIV-infected patients was evaluated. The new therapy was chosen based on the medical history procedures for 70 patients, and in 96 patients it was guided by the partial or complete result of the line probe assay (LiPA) HIV RT and Protease resistance tests. The absolute difference from the baseline of the log viral load at 3 and 6 months was significantly different between the two groups when adjusted for baseline viral load (P < 0.0001) and stayed significant when intention-to-treat analysis was carried out (P < 0.001). The absolute difference of the CD4(+) count was not significantly different when adjusted for baseline CD4(+) (P = 0.854, 3 months; P = 0.06, 6 months). The proportion of patients with a viral load =200 cp/ml in the medical history group (14.5%, 3 months; 15.2%, 6 months) was significantly different from the proportion of responders in the LiPA group (28.7%, 3 months, P = 0.03; 34.7%, 6 months, P = 0.008). In the intention-to-treat population, the difference between the two groups remained significant (P = 0.01). There was no statistical difference between the two groups in terms of adherence (P = 0.88), number of drug failures (P = 0.12) and for the time since starting treatment (in years) (P = 0.48), but there was a significant difference for the number of new drugs in the new regimen (P < 0.0001) and for the pill burden of the treatment (P = 0.0006). A higher antiretroviral HIV treatment success guided by the LiPA HIV genotyping system than that based on the medical history only is reported. Of note, this study reached the same conclusions as previous studies, which all used sequencing. 相似文献
937.
E. Estefanía N. Gmez‐Lozano R. De Pablo M. E. Moreno C. Vilches 《International journal of immunogenetics》2003,30(1):11-12
We have isolated the complete coding region of HLA‐B*39 from a Spanish Caucasoid, using a new PCR primer for its 5′ untranslated region. The cDNA matched partial genomic sequences of B*3924, an allele whose distribution appears to be restricted to Mediterranean and Arabian Caucasoids. A single amino acid change exclusive to B*3924 (threonine‐98) distinguishes it from B*3903. 相似文献
938.
Maes M De Vos N Pioli R Demedts P Wauters A Neels H Christophe A 《Journal of affective disorders》2000,58(3):241-246
OBJECTIVE: Major depression is associated with defective antioxidant defenses. Vitamin E is the major fat soluble antioxidant in the body. The aim of the present study is to examine serum vitamin E concentrations in major depressed patients versus normal volunteers. METHOD: Serum vitamin E concentrations were measured in 26 healthy volunteers and 42 major depressed patients by means of HPLC. Since vitamin E is a fat soluble vitamin, and serum vitamin E concentrations are strongly related to these of low-density-lipoprotein cholesterol (LDL-C) and triglycerides, we have adjusted the results for possible differences in these lipids. The numbers of peripheral blood leukocytes were measured. RESULTS: Patients with major depression had significantly lower serum vitamin E concentrations than healthy controls. The area under the ROC (receiver operating characteristics) curve was 83%. There were significant and negative correlations between serum vitamin E and number of total leukocytes and neutrophils. CONCLUSIONS: Major depression is accompanied by significantly lower serum vitamin E concentrations, suggesting lower antioxidant defenses against lipid peroxidation. The results could, in part, explain previous findings, which suggest increased lipid peroxidation in major depression. 相似文献
939.
Moretti S Marcellini S Boschini A Famularo G Santini G Alesse E Steinberg SM Cifone MG Kroemer G De Simone C 《Clinical and experimental immunology》2000,122(3):364-373
This study was designed to compare the degree of lymphocyte apoptosis and Fas-Fas ligand (FasL) expression in AIDS patients and long-term non-progressors (LTNPs) and correlate these parameters with apoptosis-associated perturbations in lymphocyte function. LTNPs had a lower frequency of apoptotic CD4+ and CD8+ T cells compared with subjects with AIDS. This correlated with a lower frequency of cells expressing Fas and FasL. The frequency of selected lymphocyte populations exhibiting a disrupted mitochondrial transmembrane potential (DeltaPsim) and increased superoxide generation was lower in LTNPs than in patients with AIDS; these abnormalities were associated with lower levels of caspase-1 activation in LTNPs. The results indicate a significantly reduced level of apoptosis and apoptosis-associated parameters in LTNPs than in patients developing AIDS. Based on these findings, a crucial role for mitochondria can be predicted in the process of lymphocyte apoptosis during the evolution of AIDS. 相似文献
940.
A. Canessa V. Del Bono P. De Leo N. Piersantelli A. Terragna 《European journal of clinical microbiology & infectious diseases》1992,11(2):125-130
Twenty-four consecutive HIV-positive patients affected byToxoplasma gondii encephalitis received trimethoprim-sulfamethoxazole (cotrimoxazole) as acute-phase treatment. Two dosage regimens of cotrimoxazole were used: 40 mg/kg/day (12 patients) or 120 mg/kg/day (12 patients) of total compound (trimethoprim plus sulfamethoxazole). Clinical and radiological responses to treatment were evaluated, and the product-limit method for survival data analysis was used. Eighteen of 24 patients showed both a clinical and radiological response (75 % response rate). There were no differences in response rates between patients receiving the two dosage regimens of cotrimoxazole. Adverse reaction consisted of leukopenia (two cases) and skin rash (three cases) which led to the discontinuation of the drug in one case. These results suggest that a randomized, controlled clinical trial should be carried out comparing cotrimoxazole versus sulfadiazine-pyrimethamine in AIDS patients withToxoplasma gondii encephalitis.Deceased. 相似文献