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41.
José R. Santos José A. Mu?oz-Moreno José Moltó Anna Prats Adrià Curran Pere Domingo Josep M. Llibre Daniel R. McClernon Isabel Bravo Jaume Canet Victoria Watson David Back Bonaventura Clotet 《PloS one》2013,8(7)
Background
Data on suppression of HIV replication in the CNS and on the subsequent risk of neurocognitive impairment using monotherapy with boosted protease inhibitors are limited.Methods
Ours was an exploratory cross-sectional study in patients on lopinavir/ritonavir-based monotherapy (LPV/r-MT) or standard triple therapy (LPV/r-ART) for at least 96 weeks who maintained a plasma viral load <50 copies/mL. HIV-1 RNA in CSF was determined by HIV-1 SuperLow assay (lower limit of detection, 1 copy/mL). Neurocognitive functioning was assessed using a recommended battery of neuropsychological tests covering 7 areas. Neurocognitive impairment (NCI) was determined and also a global deficit score (GDS) for study comparisons.Results
Seventeen patients on LPV/r-MT and 17 on LPV/r-ART were included. Fourteen (82.4%) patients on LPV/r-MT and 16 (94.1%) on LPV/r-ART had HIV-1 RNA <1 copy/mL in CSF (p = 0.601). NCI was observed in 7 patients on LPV/r-MT and in 10 on LPV/r-ART (41% vs 59%; p = 0.494). Mean (SD) GDS was 0.22 (0.20) in patients on LPV/r-MT and 0.47 (0.34) in those on LPV/r-ART (p = 0.012).Conclusions
Suppression of HIV in CSF is similar in individuals with durable plasma HIV-1 RNA suppression who are receiving LPV/r-MT or LPV/r-ART for at least 96 weeks. Findings for HIV-1 replication in CSF and neurocognitive status indicate that this strategy seems to be safe for CNS functioning. 相似文献42.
Barbara G Schneider M Blanca Piazuelo Liviu A Sicinschi Robertino Mera Dun-Fa Peng Juan Carlos Roa Judith Romero-Gallo Alberto G Delgado Thibaut de Sablet Luis E Bravo Keith T Wilson Wael El-Rifai Richard M Peek Jr Pelayo Correa 《Epigenetics》2013,8(11):1153-1161
DNA methylation changes are known to occur in gastric cancers and in premalignant lesions of the gastric mucosae. In order to examine variables associated with methylation levels, we quantitatively evaluated DNA methylation in tumors, non-tumor gastric mucosae, and in gastric biopsies at promoters of 5 genes with methylation alterations that discriminate gastric cancers from non-tumor epithelia (EN1, PCDH10, RSPO2, ZIC1, and ZNF610). Among Colombian subjects at high and low risk for gastric cancer, biopsies from subjects from the high-risk region had significantly higher levels of methylation at these 5 genes than samples from subjects in the low risk region (p ≤ 0.003). When results were stratified by Helicobacter pylori infection status, infection with a cagA positive, vacA s1m1 strain was significantly associated with highest methylation levels, compared with other strains (p = 0.024 to 0.001). More severe gastric inflammation and more advanced precancerous lesions were also associated with higher levels of DNA methylation (p ≤ 0.001). In a multivariate model, location of residence of the subject and the presence of cagA and vacA s1m1 in the H. pylori strain were independent variables associated with higher methylation in all 5 genes. High levels of mononuclear cell infiltration were significantly related to methylation in PCDH10, RSPO2, and ZIC1 genes. These results indicate that for these genes, levels of methylation in precancerous lesions are related to H. pylori virulence, geographic region and measures of chronic inflammation. These genes seem predisposed to sustain significant quantitative changes in DNA methylation at early stages of the gastric precancerous process. 相似文献
43.
AV Shevchenko IG Budzanivska TP Shevchenko VP Polischuk D Spaar 《Archives Of Phytopathology And Plant Protection》2013,46(2):139-146
The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants. 相似文献
44.
LEA Gene Introns: is the Intron of Dehydrin Genes a Characteristic of the Serine-Segment? 总被引:1,自引:0,他引:1
Juan Francisco Jiménez-Bremont Israel Maruri-López Ana Erika Ochoa-Alfaro Pablo Delgado-Sánchez Jaime Bravo Margarita Rodríguez-Kessler 《Plant Molecular Biology Reporter》2013,31(1):128-140
Dehydrins, which belong to group 2 LEA proteins, are a family of intrinsically unstructured plant proteins that accumulate during the late stages of embryogenesis and in response to abiotic stresses. We have previously reported that the OpsDHN1 gene, encoding an SK3-type acidic dehydrin protein from Opuntia streptacantha, contains an intron inserted within the sequence encoding the S-motif. Herein, we present an in silico analysis of intron sequences in dehydrin genes from mono- and dicotyledonous plants that reveals a preference for insertion within the nucleotide sequence encoding the S-motif. Sequence comparison of ten Dhn genes from Arabidopsis thaliana and the orthologous genes in Arabidopsis lyrata revealed that introns maintain considerable sequence identity and conserve the insertion pattern. Furthermore, syntenic regions were identified among eight orthologous genes of A. thaliana and A. lyrata, showing that correlated gene arrangements are conserved between these Arabidopsis species. Our study shows that most SKn-type dehydrins contain one intron that is conserved in phase and location; this intron is linked to the nucleotide sequence that encodes the S-motif. 相似文献
45.
46.
Andrea Gómez Bravo María Gabriela Quintana Marcelo Abril Oscar Daniel Salomón 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1071-1073
In 2004, the urban presence of Lutzomyia longipalpis was recorded
for the first time in Formosa province. In 2006, the first autochthonous case of
human urban visceral leishmaniasis (VL) was recorded in Misiones in the presence of
the vector, along with some canine VL cases. After this first case, the vector began
to spread primarily in northeast Argentina. Between 2008-2011, three human VL cases
were reported in Salta province, but the presence of Lu. longipalpis
was not recorded. Captures of Phlebotominae were made in Tartagal, Salta, in 2013,
and the presence of Lu. longipalpis was first recorded in northwest
Argentina at that time. Systematic sampling is recommended to observe the
distribution and dispersion patterns of Lu. longipalpis and consider
the risk of VL transmission in the region. 相似文献
47.
48.
Miriam Andrés Mónica Bravo Maria Antonia Buil Marta Calbet Jordi Castro Teresa Domènech Peter Eichhorn Manel Ferrer Elena Gómez Martin D. Lehner Imma Moreno Richard S. Roberts Sara Sevilla 《Bioorganic & medicinal chemistry letters》2013,23(11):3349-3353
High throughput screening identified the pyrazole-4-acetic acid substructure as CRTh2 receptor antagonists. Optimisation of the compounds uncovered a tight SAR but also identified some low nanomolar inhibitors. 相似文献
49.
Issam Arrouss Fariba Nemati Fernando Roncal Marie Wislez Karim Dorgham David Vallerand Nathalie Rabbe Narjesse Karboul Fran?oise Carlotti Jeronimo Bravo Dominique Mazier Didier Decaudin Angelita Rebollo 《PloS one》2013,8(4)