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61.

Introduction

Assessing the contextual factors that influence walking for transportation is important to develop more walkable environments and promote physical activity. To advance previous research focused on residential environments and overall walking for transportation, the present study investigates objective environmental factors assessed around the residence, the workplace, the home – work itinerary, and the home – supermarket itinerary, and considered overall walking for transportation but also walking to work and to shops.

Methods

Data from the RECORD Study involving 7290 participants recruited in 2007–2008, aged 30–79 years, and residing in the Paris metropolitan area were analyzed. Multilevel ordinal regression analyses were conducted to investigate environmental characteristics associated with self-reported overall walking for transportation, walking to work, and walking to shops.

Results

High individual education was associated with overall walking for transportation, with walking to work, and walking to shops. Among workers, a high residential neighborhood education was associated with increased overall walking for transportation, while a high workplace neighborhood education was related to an increased time spent walking to work. The residential density of destinations was positively associated with overall walking for transportation, with walking to work, and with walking to shops, while the workplace density of destinations was positively associated with overall walking for transportation among workers. Environmental factors assessed around the itineraries were not associated with walking to work or to the shops.

Conclusion

This research improves our understanding of the role of the environments on walking for transportation by accounting for some of the environments visited beyond the residential neighborhood. It shows that workers'' walking habits are more influenced by the density of destinations around the workplace than around the residence. These results provide insight for the development of policies and programs to encourage population level active commuting.  相似文献   
62.
Multiplexing was used to increase the efficiency of microsatellite analysis inEucalyptus grandis. Primers were chosen based on the range of eucalyptus SSR alleles and their hybridization temperatures. Choice of PCR conditions proved to be the most important factor; concentrations of primers must be adjusted for use in combination. Results show that 6 primers can be analyzed in 2 PCR reactions, one containing 2 and the other containing 4 primers. Multiplexing promises to be a particularly efficient tool for microsatellite diversity analysis inEucalyptus grandis.  相似文献   
63.
We investigated the prevalence and phenotypic variation of Candida species in oral lichen planus (OLP) and the therapeutic implications of our findings. Eighty patients with clinically and histopathologically confirmed cases of OLP (64 non-erosive, 16 erosive) and a control group of 80 healthy individuals with no predisposing factors for oral candidiasis were examined for evidence of Candida infection. Oral swabs and smears were obtained for cytology and culture. Identification, speciation and antifungal susceptibility tests of Candida isolates were performed using an automated microbial identification system. Fifty percent of erosive OLP cases, 28% of non-erosive cases and none of the controls showed evidence of Candida. Candida albicans was found predominantly in non-erosive OLP, while other Candida species were predominate in erosive OLP. Non-Candida albicans isolates (C. glabrata, C. krusei) were resistant to the commonly used antifungals, clotrimazole and fluconazole. Candida infection is common in cases of OLP. We recommend antifungal sensitivity testing prior to antifungal therapy for the erosive form of OLP.  相似文献   
64.
Single cell profiling was performed to assess differences in RNA accumulation in neighboring hyphae of the fungus Aspergillus niger. A protocol was developed to isolate and amplify RNA from single hyphae or parts thereof. Microarray analysis resulted in a present call for 4 to 7% of the A. niger genes, of which 12% showed heterogeneous RNA levels. These genes belonged to a wide range of gene categories.  相似文献   
65.
Chaix R  Cao C  Donnelly P 《PLoS genetics》2008,4(9):e1000184
In several species, including rodents and fish, it has been shown that the Major Histocompatibility Complex (MHC) influences mating preferences and, in some cases, that this may be mediated by preferences based on body odour. In humans, the picture has been less clear. Several studies have reported a tendency for humans to prefer MHC-dissimilar mates, a sexual selection that would favour the production of MHC-heterozygous offspring, who would be more resistant to pathogens, but these results are unsupported by other studies. Here, we report analyses of genome-wide genotype data (from the HapMap II dataset) and HLA types in African and European American couples to test whether humans tend to choose MHC-dissimilar mates. In order to distinguish MHC-specific effects from genome-wide effects, the pattern of similarity in the MHC region is compared to the pattern in the rest of the genome. African spouses show no significant pattern of similarity/dissimilarity across the MHC region (relatedness coefficient, R = 0.015, p = 0.23), whereas across the genome, they are more similar than random pairs of individuals (genome-wide R = 0.00185, p<10(-3)). We discuss several explanations for these observations, including demographic effects. On the other hand, the sampled European American couples are significantly more MHC-dissimilar than random pairs of individuals (R = -0.043, p = 0.015), and this pattern of dissimilarity is extreme when compared to the rest of the genome, both globally (genome-wide R = -0.00016, p = 0.739) and when broken into windows having the same length and recombination rate as the MHC (only nine genomic regions exhibit a higher level of genetic dissimilarity between spouses than does the MHC). This study thus supports the hypothesis that the MHC influences mate choice in some human populations.  相似文献   
66.

Background

We aimed to compare rates of virologic response and CD4 changes after combination antiretroviral (cART) initiation in individuals infected with B and specific non-B HIV subtypes.

Methods

Using CASCADE data we analyzed HIV-RNA and CD4 counts for persons infected ≥1996, ≥15 years of age. We used survival and longitudinal modeling to estimate probabilities of virologic response (confirmed HIV-RNA <500 c/ml), and failure (HIV-RNA>500 c/ml at 6 months or ≥1000 c/ml following response) and CD4 increase after cART initiation.

Results

2003 (1706 B, 142 CRF02_AG, 55 A, 53 C, 47 CRF01_AE) seroconverters were included in analysis. There was no evidence of subtype effect overall for response or failure (p = 0.075 and 0.317, respectively) although there was a suggestion that those infected with subtypes CRF01_AE and A responded sooner than those with subtype B infection [HR (95% CI):1.37 (1.01–1.86) and 1.29 (0.96–1.72), respectively]. Rates of CD4 increase were similar in all subtypes except subtype A, which tended to have lower initial, but faster long-term, increases.

Conclusions

Virologic and immunologic response to cART was similar across all studied subtypes but statistical power was limited by the rarity of some non-B subtypes. Current antiretroviral agents seem to have similar efficacy in subtype B and most widely encountered non-B infections in high-income countries.  相似文献   
67.

Background

Injurious mechanical ventilation (MV) may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investigated the effects of MV with injuriously high tidal volumes on the myocardium in an animal model of sepsis.

Methods

Normal rats and intraperitoneal (i.p.) lipopolysaccharide (LPS)-treated rats were ventilated with low (6 ml/kg) and high (19 ml/kg) tidal volumes (Vt) under general anesthesia. Non-ventilated animals served as controls. Mean arterial pressure (MAP), central venous pressure (CVP), cardiac output (CO) and pulmonary plateau pressure (Pplat) were measured. Ex vivo myocardial function was measured in isolated Langendorff-perfused hearts. Cardiac expression of endothelial vascular cell adhesion molecule (VCAM)-1 and edema were measured to evaluate endothelial inflammation and leakage.

Results

MAP decreased after LPS-treatment and Vt-dependently, both independent of each other and with interaction. MV Vt-dependently increased CVP and Pplat and decreased CO. LPS-induced peritonitis decreased myocardial function ex vivo but MV attenuated systolic dysfunction Vt-dependently. Cardiac endothelial VCAM-1 expression was increased by LPS treatment independent of MV. Cardiac edema was lowered Vt-dependently by MV, particularly after LPS, and correlated inversely with systolic myocardial function parameters ex vivo.

Conclusion

MV attenuated LPS-induced systolic myocardial dysfunction in a Vt-dependent manner. This was associated with a reduction in cardiac edema following a lower transmural coronary venous outflow pressure during LPS-induced coronary inflammation.  相似文献   
68.
Summary An allele giving rise to a polymorphism within the 3 part of the chicken vitellogenin gene was cloned, sequenced, and compared to the previously cloned allele. The polymorphism is formed by a perfect copy of 343 bp from intron 32 in tandem array with a perfect copy of 244 bp from intron 33; this 587-bp element is inserted in a head-to-tail arrangement in intron 33. We propose a mechanism in which an unequal crossing-over resulted in a vitellogenin gene with two exons 33, one of which was subsequently deleted. Thus, intron 33 was enlarged by the tandem repeats without affecting the protein-encoding sequence of the gene. At the boundaries of the repeated elements, two short direct repeats are found that resemble the recombination signals of immunoglobulin genes. They may have had a key role in the formation of the new allele.  相似文献   
69.

Introduction

We have previously demonstrated that ex vivo inhibition of costimulatory molecules on antigen-pulsed dendritic cells (DCs) can be useful for induction of antigen-specific immune deviation and suppression of autoimmune arthritis in the collagen induced arthritis (CIA) model. The current study evaluated a practical method of immune modulation through temporary systemic inhibition of the costimulatory molecule CD40.

Methods

Mice with collagen II (CII)-induced arthritis (CIA) were administered siRNA targeting the CD40 molecule. Therapeutic effects were evaluated by clinical symptoms, histopathology, Ag-specific T cell and B cell immune responses.

Results

Systemic administration of CD40-targeting siRNA can inhibit antigen-specific T cell response to collagen II, as well as prevent pathogenesis of disease in both a pre- and post-immunization manner in the CIA model. Disease amelioration was associated with suppression of Th1 cytokines, attenuation of antibody production, and upregulation of T regulatory cells.

Conclusions

These studies support the feasibility of transient gene silencing at a systemic level as a mechanism of resetting autoreactive immunity.  相似文献   
70.
A new multidetection biosensor has been developed using the electrochemical properties of cylinder-shaped conducting polypyrrole grown on miniaturized graphite electrodes. Our objective was to conceive a sensitive, labelless and real-time DNA sensor for biomedical diagnosis. In a first step, copolymers bearing both ferrocene redox markers and oligonucleotide probes were selectively electro-addressed on microchip electrodes. Then, the study of their voltammetric response upon the addition of DNA targets revealed that the hybridization was efficiently transduced through the variation of ferrocene oxidation intensity. Using this technique, a good selectivity between Human Immunodeficiency Virus and Hepatitis B Virus targets was obtained. It was indeed possible to directly follow the hybridization. Complementary DNA detection limit reached 100 pM (3 fmol in 30 microL), which represents a good performance for such a practical, labelless and real-time sensor.  相似文献   
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