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71.
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
72.
Additional human papillomavirus types detected by the hybrid capture tube test among samples from women with cytological and colposcopical atypia 总被引:3,自引:0,他引:3 下载免费PDF全文
Kónya J Veress G Juhász A Szarka K Sápy T Hernádi Z Gergely L 《Journal of clinical microbiology》2000,38(1):408-411
The type specificity of the human papillomavirus (HPV) Hybrid Capture Tube (HCT) test was evaluated by using typing with PCR (MY09-MY11)-restriction fragment length polymorphism (RFLP) and sequencing. All samples HCT test positive for only low-risk HPV (n = 15) or only high-risk HPV (n = 102) were confirmed, whereas 9 of 12 HCT test double-positive samples contained only high-risk HPV types as determined by PCR-RFLP. Several high-risk HPV types (HPV-53, -58, -62, -66, -CP8304, and -MM4) not included in the HCT test were indeed detected, indicating a broader detection range with retained distinction between low-risk and high-risk HPV types. 相似文献
73.
74.
Identification of two homologous antigenic peptides derived from L1 HPV-16 and 18 proteins specific for the HLA-B*3901 allele 总被引:1,自引:0,他引:1
Monroy-García A Weiss-Steider B Hernández-Montes J Ortiz-Navarrete VF Bañuelos-Pánuco A Acosta-Araujo A Díaz-Quiñónez A López-Graniel CM Herbert G Granados J de Leo C Silva-López RM Mora-García ML 《Archives of virology》2002,147(10):1933-1942
Summary. In this work we present evidence that the homologous peptides IHSMNSTIL and IHSMNSSIL derived from L1 HPV-16 and 18 proteins
respectively, and with high specificity for the allele HLA-B*3901, according with an algorithm prediction program, induced T cell stimulation in patients with advanced cervical cancer
positive for HPV-16 or 18 infection and for the HLA-B*3901 allele. Interestingly, T lymphocytes derived from a patient with HPV-18 infection and stimulated with the peptide IHSMNSTIL
were capable to kill a cervical cancer cell line named Rova, derived from the tumor of the same patient. In addition, the
cytotoxic activity was strongly increased when this cell line was previously treated with hrIFN-γ. These results suggest that
the CTL immune response to L1 HPV-16 and 18 protein derived epitopes is maintained in patients with advanced cervical cancer
within specific alleles, and opens the possibility that homologous epitopes may be used in the generation of prophylactic
vaccines for cervical tumors bearing different HPV-types.
Received March 4, 2002; accepted May 20, 2002 相似文献
75.
López-Ríos F Miguel PS Bellas C Ballestín C Hernández L 《Archives of pathology & laboratory medicine》2000,124(5):746-747
Lymphoepithelioma-like carcinomas have been reported outside the nasopharynx in many sites, including the uterine cervix. The association with the Epstein-Barr virus in the latter site is still controversial. To date, Epstein-Barr virus genome has only been demonstrated in Asian patients. We report a case of lymphoepithelioma-like carcinoma of the uterine cervix in a white woman in whom the Epstein-Barr virus infection was tested for by in situ hybridization and polymerase chain reaction. The results of both techniques were negative. Our case and a review of the literature support the contention that cervical lymphoepithelioma-like carcinoma is not associated with Epstein-Barr virus infection in non-Asian patients. 相似文献
76.
Bellido I Gomez-Luque A Plaza A Rius F Ortiz P Sanchez de la Cuesta F 《Neuroscience letters》2002,321(1-2):110-114
S-adenosyl-L-methionine (SAM) has shown efficacy in speeding the onset of the antidepressant effect of imipramine in depressed patients. This effect may be related to their interactions at the serotonin(1A) (5-HT(1A)) receptors. Acute imipramine up-regulated the frontal cortex 5-HT(1A) receptors (B(max), 51.5 +/- 8.4 fmol/mg protein) vs. saline (B(max), 27.5 +/- 5.9 fmol/mg protein), and did not show antidepressant effect. Acute SAM and imipramine+SAM did not modify frontal cortex 5-HT(1A) receptors, and showed antidepressant effects (decrease of the immobility response of 26%, P<0.01; and 47%, P<0.001) vs. saline. All the chronic treatments showed antidepressant effects and up-regulated the hippocampus 5-HT(1A) receptors. SAM prevents the 5-HT(1A) receptor up-regulation induced by acute imipramine in the frontal cortex. This mechanism may contribute to imipramine's antidepressant effect. 相似文献
77.
Successive stimuli of constant intensity applied to Ia afferents produce spinal monosynaptic reflexes (MSRs) of variable amplitude. We recorded simultaneous MSRs in the left and right L7 (or L6) ventral roots of anesthetized cats. We analyzed the cross-covariance (CCV) between the amplitudes of bilateral MSRs. Long-time series (5 to 8 h) of these bilateral MSRs exhibited transitory changes in their covariations (as measured by the zero-lag peak of their CCV), thus suggesting the existence of certain neural sources contributing to produce these changes. The aim of the present study was to show that spinal centers producing negative spontaneous cord dorsum potentials (nSCDPs) contribute to maintain correlations in the amplitude of bilateral MSRs. After spinal cord transection at the L1 segment, no significant changes were observed in the correlation between the amplitude of bilateral nSCDPs versus the amplitude of bilateral MSRs. However, this correlation, as well as the peak at zero lag in the CCV between bilateral MSRs and the CCV between bilateral nSCDPs, respectively, were abolished after a subsequent longitudinal bisection at the L1-S2 spinal segments. These results suggest that lumbar spinal neurons (bilaterally interconnected) contribute to maintain the synchronous fluctuations of bilateral MSRs. 相似文献
78.
Purification and partial characterization of a Paracoccidioides brasiliensis protein with capacity to bind to extracellular matrix proteins 下载免费PDF全文
González A Gómez BL Diez S Hernández O Restrepo A Hamilton AJ Cano LE 《Infection and immunity》2005,73(4):2486-2495
Microorganisms adhere to extracellular matrix proteins by means of their own surface molecules. Paracoccidioides brasiliensis conidia have been shown to be capable of interacting with extracellular matrix proteins. We aimed at determining the presence of fungal proteins that could interact with extracellular matrix protein and, if found, attempt their purification and characterization. Various extracts were prepared from P. brasiliensis mycelial and yeast cultures (total homogenates, beta-mercaptoethanol, and sodium dodecyl sulfate [SDS] extracts) and analyzed by ligand affinity assays with fibronectin, fibrinogen and laminin. Two polypeptides were detected in both fungal forms. SDS extracts that interacted with all the extracellular matrix protein were tested; their molecular masses were 19 and 32 kDa. Analysis of the N-terminal amino acid sequence of the purified 32-kDa mycelial protein showed substantial homology with P. brasiliensis, Histoplasma capsulatum, and Neurospora crassa hypothetical proteins. Additionally, a monoclonal antibody (MAb) produced against this protein recognized the 32-kDa protein in the SDS extracts of both fungal forms for immunoblot. Immunofluorescence analysis revealed that this MAb reacted not only with mycelia and yeast cells, but also with conidia, indicating that this protein was shared by the three fungal propagules. By immunoelectron microscopy, this protein was detected in the cell walls and in the cytoplasm. Both the 32-kDa purified protein and MAb inhibited the adherence of conidia to the three extracellular matrix proteins in a dose-dependent manner. These findings demonstrate the presence of two polypeptides capable of interacting with extracellular matrix proteins on the surface of P. brasiliensis propagules, indicating that there may be common receptors for laminin, fibronectin, and fibrinogen. These proteins would be crucial for initial conidial adherence and perhaps also in dissemination of paracoccidioidomycosis. 相似文献
79.
Several endocrine cell types were ultrastructurally characterized during the differentiation of the intestine and rectum of sea bass (Dicentrarchus labrax L.) larvae. Only one cell type (type I) was found in the posterior region of the undifferentiated gut of 5-day-old larvae (phase I). Types V and VI were found in both the intestine and rectum, types II, III and IV in the intestine, and types VII and VIII in the rectum of 9- and 12-day-old larvae (phase II), the rectum alone showing signs of functional differentiation. In phase III larvae, in which both the intestine and rectum were differentiated, types IX, X, XI, XII, XIII, XIV and XV were found in the intestine, only types X, XI and XII being seen in the rectum. Besides these, a new cell type, XVI, was observed in the intestine of 55- and 60-day-old larvae (phase IV), in which the digestive tract was completely differentiated. The endocrine cells appearing in phases I and II showed very scarce secretory granules and the ultrastructural features of undifferentiated cells. Some endocrine cell types in the earliest developmental stages were related to some of those found later. A maturational process of the endocrine cell types paralleled the differentiation of the intestine and rectum, with an apparent increase in the number of secretory granules accompanying organelle development. 相似文献
80.
Zúñiga J Vargas-Alarcón G Osnaya N Martínez-Tripp S Rodríguez-Reyna TS Hernández-Martinez B Hesiquio R Hernández-Pacheco G Gamboa R Juárez F Salgado N Granados J 《Genes and immunity》1999,1(1):66-68
The major histocompatibility complex (MHC) genes are highly polymorphic and therefore have been useful in population genetics and disease association studies. We analyzed restriction fragment length polymorphism of HSP70-2 alleles in healthy unrelated Mestizo, Mazatecan and Nahua populations. Both Indian groups, Mazatecans and Nahuas, were in Hardy-Weinberg equilibrium, while Mestizos were in disequilibrium (chi 2 = 0.399; P < 0.05). The Mazatecan Indians presented a high frequency of BB homozygosity (17.35%) compared to Mestizos (5%) (P = 0.01). Mexican ethnic groups present differences in distribution of BB genotype. The low frequency of BB genotype in Mestizos may be the result of a negative selection process. 相似文献