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941.
The aim of the present study was to perform a genomic analysis of non-specific lipid-transfer proteins (nsLTPs) in coffee. Several nsLTPs-encoding cDNA and gene sequences were cloned from Coffea arabica and Coffea canephora species. In this work, their analyses revealed that coffee nsLTPs belong to Type II LTP characterized under their mature forms by a molecular weight of around 7.3 kDa, a basic isoelectric points of 8.5 and the presence of typical CXC pattern, with X being an hydrophobic residue facing towards the hydrophobic cavity. Even if several single nucleotide polymorphisms were identified in these nsLTP-coding sequences, 3D predictions showed that they do not have a significant impact on protein functions. Northern blot and RT-qPCR experiments revealed specific expression of Type II nsLTPs-encoding genes in coffee fruits, mainly during the early development of endosperm of both C. arabica and C. canephora. As part of our search for tissue-specific promoters in coffee, an nsLTP promoter region of around 1.2 kb was isolated. It contained several DNA repeats including boxes identified as essential for grain specific expression in other plants. The whole fragment, and a series of 5′ deletions, were fused to the reporter gene β-glucuronidase (uidA) and analyzed in transgenic Nicotiana tabacum plants. Histochemical and fluorimetric GUS assays showed that the shorter (345 bp) and medium (827 bp) fragments of nsLTP promoter function as grain-specific promoters in transgenic tobacco plants.  相似文献   
942.
Secretion systems are specialized in transport of proteins, DNA or nutrients across the cell envelope of bacteria and enable them to communicate with their environment. The chaperone–usher (CU) pathway is used for assembly and secretion of a large family of long adhesive protein polymers, termed pili, and is widespread among Gram-negative pathogens [1]. Moreover, recent evidence has indicated that CU secretion systems are also involved in sporulation  and . In this review we focus on the structural biology of the paradigmatic type 1 and P pili CU systems encoded by uropathogenic Escherichia coli (UPEC), where recent progress has provided unprecedented insights into pilus assembly and secretion mechanism. This article is part of a Special Issue entitled: Protein trafficking and secretion in bacteria. Guest Editors: Anastassios Economou and Ross Dalbey.  相似文献   
943.

Background:

Morbidity due to cardiovascular disease is high among First Nations people. The extent to which this may be related to the likelihood of coronary angiography is unclear. We examined the likelihood of coronary angiography after acute myocardial infarction (MI) among First Nations and non–First Nations patients.

Methods:

Our study included adults with incident acute MI between 1997 and 2008 in Alberta. We determined the likelihood of angiography among First Nations and non–First Nations patients, adjusted for important confounders, using the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) database.

Results:

Of the 46 764 people with acute MI, 1043 (2.2%) were First Nations. First Nations patients were less likely to receive angiography within 1 day after acute MI (adjusted odds ratio [OR] 0.73, 95% confidence interval [CI] 0.62–0.87). Among First Nations and non–First Nations patients who underwent angiography (64.9%), there was no difference in the likelihood of percutaneous coronary intervention (PCI) (adjusted hazard ratio [HR] 0.92, 95% CI 0.83–1.02) or coronary artery bypass grafting (CABG) (adjusted HR 1.03, 95% CI 0.85–1.25). First Nations people had worse survival if they received medical management alone (adjusted HR 1.38, 95% CI 1.07–1.77) or if they underwent PCI (adjusted HR 1.38, 95% CI 1.06–1.80), whereas survival was similar among First Nations and non–First Nations patients who received CABG.

Interpretation:

First Nations people were less likely to undergo angiography after acute MI and experienced worse long-term survival compared with non–First Nations people. Efforts to improve access to angiography for First Nations people may improve outcomes.Although cardiovascular disease has been decreasing in Canada,1 First Nations people have a disproportionate burden of the disease. First Nations people in Canada have a 2.5-fold higher prevalence of cardiovascular disease than non–First Nations people,2 with hospital admissions for cardiovascular-related events also increasing.3The prevalence of cardiovascular disease in First Nations populations is presumed to be reflective of the prevalence of cardiovascular risk factors.47 However, the disproportionate increase in rates of hospital admission suggests that suboptimal management of cardiovascular disease or its risk factors may also influence patient outcomes.2,3 Racial disparities in the quality of cardiovascular care resulting in adverse outcomes have been documented, although most studies have focused on African-American, Hispanic and Asian populations.8,9 As a result, it is unclear whether suboptimal delivery of guideline-recommended treatment contributes to increased cardiovascular morbidity and mortality among First Nations people.1012We undertook a population-based study involving adults with incident acute myocardial infarction (MI) to examine the receipt of guideline-recommended coronary angiography among First Nations and non–First Nations patients.1012 Among patients who underwent angiography, we sought to determine whether there were differences between First Nations and non–First Nations patients in the likelihood of revascularization and long-term survival.  相似文献   
944.
The aim of the current study was to examine the effects of cold water immersion (CWI) with and without the free acid form of β-hydroxy-β-methylbutyrate (HMB-FA) on markers of muscle damage following acute lower body resistance exercise. Forty recreationally resistance-trained men (22.3 ± 2.4 years) were randomly divided into one of the four groups: (1) Placebo (PL); (2) HMB-FA; (3) HMB-FA-CWI; (4) PL-CWI. HMB-FA groups ingested 3 g day?1 and CWI groups submersed their lower body into 10–12 °C water for 10-min post-exercise. No differences between groups were observed for CK; however, PL-CWI had significantly greater elevations in myoglobin 30-min post-exercise compared to HMB-FA (p = 0.009) and PL (p = 0.005), and HMB-FA-CWI was significantly greater than HMB-FA (p = 0.046) and PL (p = 0.028). No differences between groups were observed for IL-6 and IL-10, although CRP was significantly greater 24-h post-exercise for PL-CWI compared to HMB-FA-CWI (p = 0.02) and HMB-FA (p = 0.046). Only HMB-FA-CWI showed significantly (p = 0.02) greater improvements in average power per repetition. CWI appeared to elevate myoglobin compared to other groups, while HMB-FA may have attenuated the increase in CRP when combined with CWI. Nevertheless, HMB-FA or CWI treatments did not appear to provide benefit over PL for recovery. Instead, the combination of CWI and HMB-FA improved performance recovery compared to other groups.  相似文献   
945.
The sequencing of libraries containing molecules shorter than the read length, such as in ancient or forensic applications, may result in the production of reads that include the adaptor, and in paired reads that overlap one another. Challenges for the processing of such reads are the accurate identification of the adaptor sequence and accurate reconstruction of the original sequence most likely to have given rise to the observed read(s). We introduce an algorithm that removes the adaptors and reconstructs the original DNA sequences using a Bayesian maximum a posteriori probability approach. Our algorithm is faster, and provides a more accurate reconstruction of the original sequence for both simulated and ancient DNA data sets, than other approaches. leeHom is released under the GPLv3 and is freely available from: https://bioinf.eva.mpg.de/leehom/  相似文献   
946.
947.

Background

Improving digestive efficiency is a major goal in poultry production, to reduce production costs, make possible the use of alternative feedstuffs and decrease the volume of manure produced. Since measuring digestive efficiency is difficult, identifying molecular markers associated with genes controlling this trait would be a valuable tool for selection. Detection of QTL (quantitative trait loci) was undertaken on 820 meat-type chickens in a F2 cross between D- and D+ lines divergently selected on low or high AMEn (apparent metabolizable energy value of diet corrected to 0 nitrogen balance) measured at three weeks in animals fed a low-quality diet. Birds were measured for 13 traits characterizing digestive efficiency (AMEn, coefficients of digestive utilization of starch, lipids, proteins and dry matter (CDUS, CDUL, CDUP, CDUDM)), anatomy of the digestive tract (relative weights of the proventriculus, gizzard and intestine and proventriculus plus gizzard (RPW, RGW, RIW, RPGW), relative length and density of the intestine (RIL, ID), ratio of proventriculus and gizzard to intestine weight (PG/I); and body weight at 23 days of age. Animals were genotyped for 6000 SNPs (single nucleotide polymorphisms) distributed on 28 autosomes, the Z chromosome and one unassigned linkage group.

Results

Nine QTL for digestive efficiency traits, 11 QTL for anatomy-related traits and two QTL for body weight at 23 days of age were detected. On chromosome 20, two significant QTL at the genome level co-localized for CDUS and CDUDM, i.e. two traits that are highly correlated genetically. Moreover, on chromosome 16, chromosome-wide QTL for AMEn, CDUS, CDUDM and CDUP, on chromosomes 23 and 26, chromosome-wide QTL for CDUS, on chromosomes 16 and 26, co-localized QTL for digestive efficiency and the ratio of intestine length to body weight and on chromosome 27 a chromosome-wide QTL for CDUDM were identified.

Conclusions

This study identified several regions of the chicken genome involved in the control of digestive efficiency. Further studies are necessary to identify the underlying genes and to validate these in commercial populations and breeding environments.  相似文献   
948.
Apert syndrome is a genetic disorder known as acrocephalopolysyndactyly type 1 caused by mutations in the fibroblast growth factor receptor 2 and characterized by coronal craniosynostosis, symmetric bone and skin syndactyly of hands and feet, and craniofacial dysmorphic features. The estimated prevalence of this syndrome is 10 to 15.5 cases per 1,000,000 live births. Apert syndrome has considerable clinical variability. We present a case of Apert syndrome and associated features reported to the National Registry of Congenital Anomalies of Argentina (RENAC). The reported case had omphalocele, esophageal atresia, and mega cisterna magna. The last two signs were reported several times as part of the clinical presentation of Apert syndrome. To our knowledge, this is the second reported case diagnosed with Apert syndrome associated with omphalocele. Birth Defects Research (Part A), 100:726–729, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
949.
Seroprevalence survey is the most practical method for accurately estimating infection attack rate (IAR) in an epidemic such as influenza. These studies typically entail selecting an arbitrary titer threshold for seropositivity (e.g. microneutralization [MN] 1∶40) and assuming the probability of seropositivity given infection (infection-seropositivity probability, ISP) is 100% or similar to that among clinical cases. We hypothesize that such conventions are not necessarily robust because different thresholds may result in different IAR estimates and serologic responses of clinical cases may not be representative. To illustrate our hypothesis, we used an age-structured transmission model to fully characterize the transmission dynamics and seroprevalence rises of 2009 influenza pandemic A/H1N1 (pdmH1N1) during its first wave in Hong Kong. We estimated that while 99% of pdmH1N1 infections became MN1∶20 seropositive, only 72%, 62%, 58% and 34% of infections among age 3–12, 13–19, 20–29, 30–59 became MN1∶40 seropositive, which was much lower than the 90%–100% observed among clinical cases. The fitted model was consistent with prevailing consensus on pdmH1N1 transmission characteristics (e.g. initial reproductive number of 1.28 and mean generation time of 2.4 days which were within the consensus range), hence our ISP estimates were consistent with the transmission dynamics and temporal buildup of population-level immunity. IAR estimates in influenza seroprevalence studies are sensitive to seropositivity thresholds and ISP adjustments which in current practice are mostly chosen based on conventions instead of systematic criteria. Our results thus highlighted the need for reexamining conventional practice to develop standards for analyzing influenza serologic data (e.g. real-time assessment of bias in ISP adjustments by evaluating the consistency of IAR across multiple thresholds and with mixture models), especially in the context of pandemics when robustness and comparability of IAR estimates are most needed for informing situational awareness and risk assessment. The same principles are broadly applicable for seroprevalence studies of other infectious disease outbreaks.  相似文献   
950.
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