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61.
Пользуясь методом хроматографии с высаливанием (salting-out paper chromatogram), мы исследовали 19 антибиотиков из грибков. В 10 случаях мы установили принадлежность к 1-й группе, в 4 случаях—принадлежность к 3-й группе и в 5 случаях—принадлежность к 4-й группе. 相似文献
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63.
Fernando Zamarreño Fernando E. Herrera Betina Córsico Marcelo D. Costabel 《生物化学与生物物理学报:生物膜》2012,1818(7):1691-1697
The role of fatty acid binding proteins as intracellular fatty acid transporters may require their direct interaction with membranes. In this way different mechanisms have been previously characterized through experimental studies suggesting different models for FABPs–membrane association, although the process in which the molecule adsorbs to the membrane remains to be elucidated. To estimate the importance of the electrostatic energy in the FABP–membrane interaction, we computationally modeled the interaction of different FABPs with both anionic and neutral membranes. Free Electrostatic Energy of Binding (dE), was computed using Finite Difference Poisson Boltzmann Equation (FDPB) method as implemented in APBS (Adaptive Poisson Boltzmann Solver). Based on the computational analysis, it is found that recruitment to membranes is facilitated by non-specific electrostatic interactions. Also energetic analysis can quantitatively differentiate among the mechanisms of membrane association proposed and determinate the most energetically favorable configuration for the membrane-associated states of different FABPs. This type of calculations could provide a starting point for further computational or experimental analysis. 相似文献
64.
Tauro L Marino B Diaz LA Lucca E Gallozo D Spinsanti L Contigiani M 《Memórias do Instituto Oswaldo Cruz》2012,107(4):553-556
St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) present ecological and antigenic similarities and are responsible for serious human diseases. In addition, WNV is a significant pathogen in terms of equine health. The purpose of our study was to analyse the seroprevalence of SLEV and WNV in equine sera collected in Santa Fe Province, Argentina. The seroprevalence determined using the plaque reduction neutralisation test was 12.2% for SLEV, 16.2% for WNV and 48.6% for a combination of both viruses. These results provide evidence of the co-circulation of SLEV and WNV in equines in Santa Fe. 相似文献
65.
Betina Biagetti Andrea Ciudin Marina Portela Belen Dalama Jordi Mesa 《Endocrinología y nutrición》2012,59(7):423-428
Background and objectiveIn many hospitals, adequate glycemic control is not achieved despite implementation of new insulin therapy protocols. Our aim was to assess resident physician’ attitudes toward inpatient hyperglycemia, barriers to achieve optimum control, and impact on them of an insulin training programMaterial and methodsA questionnaire was used to assess understanding and standard management of hyperglycemia before and six months after implementation of an inpatient insulin treatment program.ResultsTwenty-five interns completed the questionnaire. Glycemic control was considered “very important” in all admission situations, but was only considered “very important” in conventional hospitalization by 36% of interns. Most of these felt “comfortable” using sliding scales, but not with the basal/bolus regimen, which was the least commonly used. Perception of number of well-controlled patients and comfort and use of basal/bolus therapy increased at six months, but use of “sliding scales” remained high. The greatest difficulty reported for adequate management of hyperglycemia was the lack of knowledge.ConclusionsMost residents are aware of the importance of adequate glycemic control, but cannot achieve it because of inadequate knowledge. The insulin training program led to an improved perception and applicability of basal-bolus insulin regimens. However, despite all efforts, use of sliding scales remains high. Training programs should emphasize management of hyperglycemia. 相似文献
66.
Glial fibrillary acidic protein (GFAP) is an intermediate filament (IF) protein specific to central nervous system (CNS) astrocytes. It has been the subject of intense interest due to its association with neurodegenerative diseases, and because of growing evidence that IF proteins not only modulate cellular structure, but also cellular function. Moreover, GFAP has a family of splicing isoforms apparently more complex than that of other CNS IF proteins, consistent with it possessing a range of functional and structural roles. The gene consists of 9 exons, and to date all isoforms associated with 3' end splicing have been identified from modifications within intron 7, resulting in the generation of exon 7a (GFAPδ/ε) and 7b (GFAPκ). To better understand the nature and functional significance of variation in this region, we used a Bayesian multiple change-point approach to identify conserved regions. This is the first successful application of this method to a single gene--it has previously only been used in whole-genome analyses. We identified several highly or moderately conserved regions throughout the intron 7/7a/7b regions, including untranslated regions and regulatory features, consistent with the biology of GFAP. Several putative unconfirmed features were also identified, including a possible new isoform. We then integrated multiple computational analyses on both the DNA and protein sequences from the mouse, rat and human, showing that the major isoform, GFAPα, has highly conserved structure and features across the three species, whereas the minor isoforms GFAPδ/ε and GFAPκ have low conservation of structure and features at the distal 3' end, both relative to each other and relative to GFAPα. The overall picture suggests distinct and tightly regulated functions for the 3' end isoforms, consistent with complex astrocyte biology. The results illustrate a computational approach for characterising splicing isoform families, using both DNA and protein sequences. 相似文献
67.
Pacheco AG Durovni B Cavalcante SC Lauria LM Moore RD Moulton LH Chaisson RE Golub JE 《PloS one》2008,3(9):e3132
Background
We studied the incidence of tuberculosis, AIDS, AIDS deaths and AIDS-TB co-infection at the population level in Rio de Janeiro, Brazil where universal and free access to combination antiretroviral therapy has been available since 1997.Methodology/Principal Findings
This was a retrospective surveillance database match of Rio de Janeiro databases from 1995–2004. Proportions of tuberculosis occurring within 30 days and between 30 days and 1 year after AIDS diagnosis were determined. Generalized additive models fitted with cubic splines with appropriate estimating methods were used to describe rates and proportions over time. Overall, 90,806 tuberculosis cases and 16,891 AIDS cases were reported; 3,125 tuberculosis cases within 1 year of AIDS diagnosis were detected. Tuberculosis notification rates decreased after 1997 from a fitted rate (fR per 100,000) of 166.5 to 138.8 in 2004. AIDS incidence rates increased 26% between 1995 and 1998 (30.7 to 38.7) followed by a 33.3% decrease to 25.8 in 2004. AIDS mortality rates decreased dramatically after antiretroviral therapy was introduced between 1995 (27.5) and 1999 (13.4). The fitted proportion (fP) of patients with tuberculosis diagnosed within one year of AIDS decreased from 1995 (24.4%) to1998 (15.2%), remaining stable since. Seventy-five percent of tuberculosis diagnoses after an AIDS diagnosis occurred within 30 days of AIDS diagnosis.Conclusions/Significance
Our results suggest that while combination ART should be considered an essential component of the response to the HIV and HIV/tuberculosis epidemics, it may not be sufficient alone to prevent progression from latent TB to active disease among HIV-infected populations. When tuberculosis is diagnosed prior to or at the same time as AIDS and ART has not yet been initiated, then ART is ineffective as a tuberculosis prevention strategy for these patients. Earlier HIV/AIDS diagnosis and ART initiation may reduce TB incidence in HIV/AIDS patients. More specific interventions will be required if HIV-related tuberculosis incidence is to continue to decline. 相似文献68.
Tea Skaaby Lise Lotte Nystrup Husemoen Torben Martinussen Jacob P. Thyssen Michael Melgaard Betina Heinsb?k Thuesen Charlotta Pisinger Torben J?rgensen Jeanne D. Johansen Torkil Menné Berit Carlsen Pal B. Szecsi Steen Stender Runa Vavia Fenger Mogens Fenger Allan Linneberg 《PloS one》2013,8(2)
Background
Vitamin D deficiency is associated with increased cardiovascular disease risk in observational studies. Whether these associations are causal is not clear. Loss-of-function mutations in the filaggrin gene result in up to 10% higher serum vitamin D concentrations, supposedly due to a decreased UV-protection of the keratinocytes. We used a Mendelian randomization approach to estimate the causal effect of vitamin D status on serum lipids, blood pressure, body mass index, waist circumference, and the metabolic syndrome.Methods
Three population based studies were included, Monica10 (2,656 individuals aged 40–71 years), Inter99 (6,784 individuals aged 30–60 years), and Health2006 (3,471 individuals aged 18–69 years) conducted in 1993–94, 1999–2001, and 2006–2008, respectively. Participants were genotyped for the two most common filaggrin gene mutations in European descendants R501X and 2282del4, in all three studies and further for the R2447X mutation in the Inter99 and Health2006 studies. Filaggrin genotype was used as instrumental variable for vitamin D status. Baseline measurements of serum 25-hydroxyvitamin D were performed in all three studies.Results
Instrumental variable analyses showed a 23.8% (95% confidence interval, CI 3.0, 48.6) higher HDL cholesterol level and a 30.5% (95% CI: 0.8, 51.3) lower serum level of triglycerides per doubling of vitamin D. These associations were, however, not statistically significant when applying the Bonferroni adjusted significance level. The remaining lipids showed non-significant changes in a favorable direction. Doubling of vitamin D gave a non-significantly lower odds ratio = 0.26 (95% CI: 0.06, 1.17) of the metabolic syndrome. There were no statistically significant causal effects of vitamin D status on blood pressure, body mass index, or waist circumference.Conclusion
Our results support a causal effect of higher vitamin D status on a more favorable lipid profile, although more studies in other populations are needed to confirm our results. 相似文献69.
Marí C. Santos Krissie D. Soares Betina M. Beltrame Natally S. B. Toson Maria do Carmo B. Pimentel Sérgio A. L. Bordignon Miriam A. Apel Andreas S. L. Mendez Amélia T. Henriques 《化学与生物多样性》2021,18(7):e2100041
The present study investigates the chemical composition, anti-inflammatory, and antihypertensive activities, in vitro, from extracts of Cuphea lindmaniana and Cuphea urbaniana leaves. The extraction was performed ultrasound-assisted, and UHPLC/MS analysis was in positive mode ionization. The anti-inflammatory activity of the extracts and miquelianin were assayed at concentrations 0.001–10 μg/mL by chemotaxis on rat polymorphonuclear neutrophils. The antihypertensive activity was performed by angiotensin-converting enzyme (ACE) inhibition. From the nineteen proposed compounds, six of them are described for the first time in this genus. The extracts displayed antichemotactic effect with a reduction of 100 % of the neutrophil migration, in vitro, in most concentrations. The ACE-inhibition presented results ranging from 19.58 to 22.82 %. In conclusion, C. lindmaniana and C. urbaniana extracts contain a rich diversity of flavonoids and display in vitro anti-inflammatory and antihypertensive potential. Thus, this study could serve as a scientific baseline for further investigation, on developmental novel products with therapeutic actions. 相似文献
70.
AimsAssessing the role of a dominant native bamboo species on tree species diversity and structure in the medium term. 相似文献