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991.

Background

In many communities, older men (i.e., over 25 years of age) have not come forward for Voluntary Medical Male Circumcision (VMMC) services. Reasons for low demand among this group of men are not well understood, and may vary across geographic and cultural contexts. This paper examines the facilitators and barriers to VMMC demand in Turkana County, Kenya, with a focus on older men. This is one of the regions targeted by the VMMC program in Kenya because the Turkana ethnic group does not traditionally circumcise, and the rates of HIV and STD transmission are high.

Methods and Findings

Twenty focus group discussions and 69 in-depth interviews were conducted with circumcised and uncircumcised men and their partners to elicit their attitudes and perceptions toward male circumcision. The interviews were conducted in urban, peri-urban, and rural communities across Turkana. Our results show that barriers to circumcision include stigma associated with VMMC, the perception of low risk for HIV for older men and their “protection by marriage,” cultural norms, and a lack of health infrastructure. Facilitators include stigma against not being circumcised (since circumcision is associated with modernity), protection against disease including HIV, and cleanliness. It was also noted that older men should adopt the practice to serve as role models to younger men.

Conclusions

Both men and women were generally supportive of VMMC, but overcoming barriers with appropriate communication messages and high quality services will be challenging. The justification of circumcision being a biomedical procedure for protection against HIV will be the most important message for any communication strategy.  相似文献   
992.

Background

SYMMACS, the Systematic Monitoring of the Voluntary Medical Male Circumcision Scale-up, tracked the implementation and adoption of six elements of surgical efficiency— use of multiple surgical beds, pre-bundled kits, task shifting, task sharing, forceps-guided surgical method, and electrocautery—as standards of surgical efficiency in Kenya, South Africa, Tanzania, and Zimbabwe.

Methods and Findings

This multi-country study used two-staged sampling. The first stage sampled VMMC sites: 73 in 2011, 122 in 2012. The second stage involved sampling providers (358 in 2011, 591 in 2012) and VMMC procedures for observation (594 in 2011, 1034 in 2012). The number of VMMC sites increased significantly between 2011 and 2012; marked seasonal variation occurred in peak periods for VMMC. Countries adopted between three and five of the six elements; forceps-guided surgery was the only element adopted by all countries. Kenya and Tanzania routinely practiced task-shifting. South Africa and Zimbabwe used pre-bundled kits with disposable instruments and electrocautery. South Africa, Tanzania, and Zimbabwe routinely employed multiple surgical bays.

Conclusions

SYMMACS is the first study to provide data on the implementation of VMMC programs and adoption of elements of surgical efficiency. Findings have contributed to policy change on task-shifting in Zimbabwe, a review of the monitoring system for adverse events in South Africa, an increased use of commercially bundled VMMC kits in Tanzania, and policy dialogue on improving VMMC service delivery in Kenya. This article serves as an overview for five other articles following this supplement.  相似文献   
993.
As a result of expanding scientific understanding of the interplay between genetics and dietary risk factors, those involved in nutritional management need to understand genetics and nutritional genomics in order to inform management of individuals and groups. The aim of this study was to measure and determine factors affecting dietitians’ knowledge, involvement and confidence in genetics and nutritional genomics across the US, Australia and the UK. A cross-sectional study was undertaken using an online questionnaire that measured knowledge and current involvement and confidence in genetics and nutritional genomics. The questionnaire was distributed to dietitians in the US, Australia and the UK using email lists from the relevant professional associations. Data were collected from 1,844 dietitians who had practiced in the previous 6 months. The main outcomes were knowledge of genetics and nutritional genomics and involvement and confidence in undertaking clinical and educational activities related to genetics and nutritional genomics. Mean scores for knowledge, involvement and confidence were calculated. Analysis of variance and χ 2 analysis were used to compare scores and frequencies. Multivariate linear regression was used to determine predictors of high scores. The results demonstrated significant differences in involvement (p < 0.001) and confidence (p < 0.001) but not knowledge scores (p = 0.119) between countries. Overall, dietitians reported low levels of knowledge (mean knowledge score 56.3 %), involvement (mean number of activities undertaken 20.0–22.7 %) and confidence (mean confidence score 25.8–29.7 %). Significant relationships between confidence, involvement and knowledge were observed. Variables relating to education, experience, sector of employment and attitudes were also significantly associated with knowledge, involvement and confidence. Dietitians’ knowledge, involvement and confidence relating to genetics and nutritional genomics remain low and further investigation into factors contributing to this is required.  相似文献   
994.
The ubiquitin proteasome system (UPS) is the major pathway of intracellular protein degradation and may be involved in the pathophysiology of inflammatory bowel diseases or irritable bowel syndrome. UPS specifically degrades proteins tagged with an ubiquitin chain. We aimed to identify polyubiquitinated proteins during inflammatory response in intestinal epithelial HCT‐8 cells by a proteomic approach. HCT‐8 cells were incubated with interleukin 1β, tumor necrosis factor‐α, and interferon‐γ for 2 h. Total cellular protein extracts were separated by 2D gel electrophoresis and analyzed by an immunodetection using antiubiquitin antibody. Differential ubiquitinated proteins were then identified by LC‐ESI MS/MS. Seven proteins were differentially ubiquitinated between control and inflammatory conditions. Three of them were chaperones: Grp75 and Hsc70 were more ubiquitinated (p < 0.05) and Grp78 was less ubiquitinated (p < 0.05) under inflammatory conditions. The results for Grp75 and Grp78 were then confirmed in HCT‐8 cells and in 2‐4‐6‐trinitrobenzen sulfonic acid induced colitis in rats mimicking inflammatory bowel disease by immunoprecipitation. No difference was observed in irritable bowel syndrome like model. In conclusion, we showed that a proteomic approach is suitable to identify ubiquitinated proteins and that UPS‐regulated expression of Grp75 and Grp78 may be involved in inflammatory response. Further studies should lead to the identification of ubiquitin ligases responsible for Grp75 and Grp78 ubiquitination.  相似文献   
995.
Abstract

A short synthetic route to an appropriately derivatized carbocyclic analogue of abasic site residues of DNA is proposed.  相似文献   
996.
Cyanide-resistant non-phosphorylating respiration is known in mitochondria from plants, fungi, and microorganisms but is absent in mammals. It results from the activity of an alternative oxidase (AOX) that conveys electrons directly from the respiratory chain (RC) ubiquinol pool to oxygen. AOX thus provides a bypath that releases constraints on the cytochrome pathway and prevents the over-reduction of the ubiquinone pool, a major source of superoxide. RC dysfunctions and deleterious superoxide overproduction are recurrent themes in human pathologies, ranging from neurodegenerative diseases to cancer, and may be instrumental in ageing. Thus, preventing RC blockade and excess superoxide production by means of AOX should be of considerable interest. However, because of its energy-dissipating properties, AOX might produce deleterious effects of its own in mammals. Here we show that AOX can be safely expressed in the mouse (MitAOX), with major physiological parameters being unaffected. It neither disrupted the activity of other RC components nor decreased oxidative phosphorylation in isolated mitochondria. It conferred cyanide-resistance to mitochondrial substrate oxidation and decreased reactive oxygen species (ROS) production upon RC blockade. Accordingly, AOX expression was able to support cyanide-resistant respiration by intact organs and to afford prolonged protection against a lethal concentration of gaseous cyanide in whole animals. Taken together, these results indicate that AOX expression in the mouse is innocuous and permits to overcome a RC blockade, while reducing associated oxidative insult. Therefore, the MitAOX mice represent a valuable tool in order to investigate the ability of AOX to counteract the panoply of mitochondrial-inherited diseases originating from oxidative phosphorylation defects.  相似文献   
997.
Summary

This study examines the possible action of copper on advanced glycation. Copper has been shown to induce fluorescence due to advanced-glycated-end-products (AGEs) on albumin incubated with glucose, and this was interpreted as activation of the glucose or Amadori product (AP) autoxidation. We glycated albumin (60 g/L) to several levels with increasing concentrations of glucose. The dialysed glucose-free glycated albumin was then incubated with 1.5 μmol/L copper or 1 mmol/L diethylenetriaminepentaacetic acid (DTPA), plus or minus glucose. The production of AP, measured as furosine, was similar whether DTPA or copper was present in the incubation medium. It linearly increased as a function of time and glucose concentration in both cases up to a maximum (furosine around 20 mmol/g protein), indicating saturation of the free NH2 residues on the protein. The fluorescence due to AGEs increased linearly over time for glycated albumin incubated without glucose, and exponentially when glucose was added to the incubation medium. This fluorescence was also unaffected by DTPA or copper for a glucose concentration below 125 mmol/L and initial furosine below 10 mmol/g. However copper caused a slight activation in samples with very high glucose (1.25 mol/L) and furosine (30–40 mmol/g) concentrations. We therefore find no effect of copper in this experiment, because the copper concentration is lower and the albumin higher than that used in previous studies. In these conditions, albumin chelates copper and inhibits its oxidative activity. The protein concentrations used in most in vitro studies showing a copper effect were below 10 g/L with copper often above 10 μmol/L, so that copper may act oxidatively. As the lens and arterial wall have high protein concentrations, copper should have no action on protein glycation in vivo, unless altered protein structure impedes the inactivation of copper by chelation.  相似文献   
998.
999.
1000.

Background

Apiculture has been practiced in North Africa and the Middle-East from antiquity. Several thousand years of selective breeding have left a mosaic of Apis mellifera subspecies in the Middle-East, many uniquely adapted and survived to local environmental conditions. In this study we explore the genetic diversity of A. mellifera from Syria (n?=?1258), Lebanon (n?=?169) and Iraq (n?=?35) based on 14 short tandem repeat (STR) loci in the context of reference populations from throughout the Old World (n?=?732).

Results

Our data suggest that the Syrian honeybee Apis mellifera syriaca occurs in both Syrian and Lebanese territories, with no significant genetic variability between respective populations from Syria and Lebanon. All studied populations clustered within a new fifth independent nuclear cluster, congruent with an mtDNA Z haplotype identified in a previous study. Syrian honeybee populations are not associated with Oriental lineage O, except for sporadic introgression into some populations close to the Turkish and Iraqi borders. Southern Syrian and Lebanese populations demonstrated high levels of genetic diversity compared to the northern populations.

Conclusion

This study revealed the effects of foreign queen importations on Syrian bee populations, especially for the region of Tartus, where extensive introgression of A. m. anatolica and/or A. m. caucasica alleles were identified. The policy of creating genetic conservation centers for the Syrian subspecies should take into consideration the influence of the oriental lineage O from the northern Syrian border and the large population of genetically divergent indigenous honeybees located in southern Syria.
  相似文献   
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