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991.
The performance of hybridization capture combined with next‐generation sequencing (NGS) has seen limited investigation with samples from hot and arid regions until now. We applied hybridization capture and shotgun sequencing to recover DNA sequences from bone specimens of ancient‐domestic dromedary (Camelus dromedarius) and its extinct ancestor, the wild dromedary from Jordan, Syria, Turkey and the Arabian Peninsula, respectively. Our results show that hybridization capture increased the percentage of mitochondrial DNA (mtDNA) recovery by an average 187‐fold and in some cases yielded virtually complete mitochondrial (mt) genomes at multifold coverage in a single capture experiment. Furthermore, we tested the effect of hybridization temperature and time by using a touchdown approach on a limited number of samples. We observed no significant difference in the number of unique dromedary mtDNA reads retrieved with the standard capture compared to the touchdown method. In total, we obtained 14 partial mitochondrial genomes from ancient‐domestic dromedaries with 17–95% length coverage and 1.27–47.1‐fold read depths for the covered regions. Using whole‐genome shotgun sequencing, we successfully recovered endogenous dromedary nuclear DNA (nuDNA) from domestic and wild dromedary specimens with 1–1.06‐fold read depths for covered regions. Our results highlight that despite recent methodological advances, obtaining ancient DNA (aDNA) from specimens recovered from hot, arid environments is still problematic. Hybridization protocols require specific optimization, and samples at the limit of DNA preservation need multiple replications of DNA extraction and hybridization capture as has been shown previously for Middle Pleistocene specimens.  相似文献   
992.

Background

Thoracotomy is associated with severe pain that may persist for years. Acupuncture is a complementary therapy with a proven role in pain control. A randomized trial showed that acupuncture was effective in controlling pain after abdominal surgery, but the efficacy of this technique for the treatment of thoracotomy pain has not been established. We developed a novel technique for convenient application of acupuncture to patients undergoing thoracotomy, and in a Phase II trial evaluated the safety of this intervention and the feasibility of doing a randomized trial.

Methods

Adult patients scheduled for unilateral thoracotomy with preoperative epidural catheter placement received acupuncture immediately prior to surgery. Eighteen semi-permanent intradermal needles were inserted on either side of the spine, and four were inserted in the legs and auricles. Needles were removed after four weeks. Using a numerical rating scale, pain was measured on the first five postoperative days. After discharge, pain was assessed using the Brief Pain Inventory at 7, 30, 60 and 90 days.

Results

Thirty-six patients were treated with acupuncture. Of these, 25, 23, and 22 patients provided data at 30, 60, and 90 days, respectively. The intervention was well tolerated by patients with only one minor and transient adverse event of skin ulceration.

Conclusion

The rate of data completion met our predefined criterion for determining a randomized trial to be feasible (at least 75% of patients tolerated the intervention and provided evaluable data). This novel intervention is acceptable to patients undergoing thoracotomy and does not interfere with standard preoperative care. There was no evidence of important adverse events. We are now testing the hypothesis that acupuncture significantly adds to standard perioperative pain management in a randomized trial.  相似文献   
993.
Wolf herrings (Chirocentridae; Clupeoidei) are commonly found in local fish markets throughout the Indo‐West Pacific region where they constitute an auxiliary source of food and income for local communities. The validity of the two species of wolf herrings, Chirocentrus dorab Forsskål, 1775 and C. nudus Swainon, 1839, is only supported by slight morphological differences. The identification of either species is challenging, especially for juveniles, and precludes accurate assessments of these natural resources at a species level. As a step towards gaining better knowledge of the genetic structure of these fishes, we examined genetic differentiation between these two species by reconstructing their entire mitogenomic sequences using high‐throughput sequencing technology. We found that the mitogenome of each species shared the same gene content and order that were the same for those found in most other teleost fishes. Despite their high morphological similarity, these two species of Chirocentrus were genetically well differentiated (p‐distance = 16.3% at their cytochrome oxidase I). A mitogenomic time‐calibrated phylogenetic analysis showed that wolf herrings originated about 35 million years ago, and they represent a case of morphological stasis. Furthermore, comparison of published and newly determined mitochondrial COI barcode region sequences from 22 individuals revealed species‐level cryptic genetic diversity within C. dorab. Altogether, these mitochondrial data are effective in discriminating species within this genus and informing population genetic relationships within species of wolf herrings.  相似文献   
994.

Background  

Damask roses (Rosa damascena Mill.) are mainly used for essential oil production. Previous studies have indicated that all production material in Bulgaria and Turkey consists of only one genotype. Nine polymorphic microsatellite markers were used to analyze the genetic diversity of 40 accessions of R. damascena collected across major and minor rose oil production areas in Iran.  相似文献   
995.

Background  

Lymphocyte function-associated antigen-1 (LFA-1, CD11a/CD18, alphaLbeta2), the most abundant and widely expressed beta2-integrin, is required for many cellular adhesive interactions during the immune response. Many studies have shown that LFA-1 is centrally involved in the pathogenesis of several diseases caused by Repeats-in-toxin (RTX) -producing bacteria.  相似文献   
996.

Background

Parkinson''s disease is characterized by the presence of cytoplasmic inclusions, known as Lewy bodies, containing both aggregated α-synuclein and its interaction partner, synphilin-1. While synphilin-1 is known to accelerate inclusion formation by α-synuclein in mammalian cells, its effect on cytotoxicity remains elusive.

Methodology/Principal Findings

We expressed wild-type synphilin-1 or its R621C mutant either alone or in combination with α-synuclein in the yeast Saccharomyces cerevisiae and monitored the intracellular localization and inclusion formation of the proteins as well as the repercussions on growth, oxidative stress and cell death. We found that wild-type and mutant synphilin-1 formed inclusions and accelerated inclusion formation by α-synuclein in yeast cells, the latter being correlated to enhanced phosphorylation of serine-129. Synphilin-1 inclusions co-localized with lipid droplets and endomembranes. Consistently, we found that wild-type and mutant synphilin-1 interacts with detergent-resistant membrane domains, known as lipid rafts. The expression of synphilin-1 did not incite a marked growth defect in exponential cultures, which is likely due to the formation of aggresomes and the retrograde transport of inclusions from the daughter cells back to the mother cells. However, when the cultures approached stationary phase and during subsequent ageing of the yeast cells, both wild-type and mutant synphilin-1 reduced survival and triggered apoptotic and necrotic cell death, albeit to a different extent. Most interestingly, synphilin-1 did not trigger cytotoxicity in ageing cells lacking the sirtuin Sir2. This indicates that the expression of synphilin-1 in wild-type cells causes the deregulation of Sir2-dependent processes, such as the maintenance of the autophagic flux in response to nutrient starvation.

Conclusions/Significance

Our findings demonstrate that wild-type and mutant synphilin-1 are lipid raft interacting proteins that form inclusions and accelerate inclusion formation of α-synuclein when expressed in yeast. Synphilin-1 thereby induces cytotoxicity, an effect most pronounced for the wild-type protein and mediated via Sir2-dependent processes.  相似文献   
997.
We performed genome-wide homozygosity mapping in a large consanguineous family from Morocco and mapped the autosomal-recessive nonsyndromic hearing loss (ARNSHL) in this family to the DFNB79 locus on chromosome 9q34. By sequencing of 62 positional candidate genes of the critical region, we identified a causative homozygous 11 bp deletion, c.42_52del, in the TPRN gene in all seven affected individuals. The deletion is located in exon 1 and results in a frameshift and premature protein truncation (p.Gly15AlafsX150). Interestingly, the deleted sequence is part of a repetitive and CG-rich motive predicted to be prone to structural aberrations during crossover formation. We identified another family with progressive ARNSHL linked to this locus, whose affected members were shown to carry a causative 1 bp deletion (c.1347delG) in exon 1 of TPRN. The function of the encoded protein, taperin, is unknown; yet, partial homology to the actin-caping protein phostensin suggests a role in actin dynamics.  相似文献   
998.
The trend towards realistic numerical models of (pathologic) patient-specific vascular structures brings along larger computational domains and more complex geometries, increasing both the computation time and the operator time. Hexahedral grids effectively lower the computational run time and the required computational infrastructure, but at high cost in terms of operator time and minimal cell quality, especially when the computational analyses are targeting complex geometries such as aneurysm necks, severe stenoses and bifurcations. Moreover, such grids generally do not allow local refinements. As an attempt to overcome these limitations, a novel approach to hexahedral meshing is proposed in this paper, which combines the automated generation of multi-block structures with a grid-based method. The robustness of the novel approach is tested on common complex geometries, such as tree-like structures (including trifurcations), stenoses, and aneurysms. Additionally, the performance of the generated grid is assessed using two numerical examples. In the first example, a grid sensitivity analysis is performed for blood flow simulated in an abdominal mouse aorta and compared to tetrahedral grids with a prismatic boundary layer. In the second example, the fluid–structure interaction in a model of an aorta with aortic coarctation is simulated and the effect of local grid refinement is analyzed.  相似文献   
999.
In recent years the role of FSI (fluid-structure interaction) simulations in the analysis of the fluid-mechanics of heart valves is becoming more and more important, being able to capture the interaction between the blood and both the surrounding biological tissues and the valve itself. When setting up an FSI simulation, several choices have to be made to select the most suitable approach for the case of interest: in particular, to simulate flexible leaflet cardiac valves, the type of discretization of the fluid domain is crucial, which can be described with an ALE (Arbitrary Lagrangian-Eulerian) or an Eulerian formulation. The majority of the reported 3D heart valve FSI simulations are performed with the Eulerian formulation, allowing for large deformations of the domains without compromising the quality of the fluid grid. Nevertheless, it is known that the ALE-FSI approach guarantees more accurate results at the interface between the solid and the fluid. The goal of this paper is to describe the same aortic valve model in the two cases, comparing the performances of an ALE-based FSI solution and an Eulerian-based FSI approach. After a first simplified 2D case, the aortic geometry was considered in a full 3D set-up. The model was kept as similar as possible in the two settings, to better compare the simulations’ outcomes. Although for the 2D case the differences were unsubstantial, in our experience the performance of a full 3D ALE-FSI simulation was significantly limited by the technical problems and requirements inherent to the ALE formulation, mainly related to the mesh motion and deformation of the fluid domain. As a secondary outcome of this work, it is important to point out that the choice of the solver also influenced the reliability of the final results.  相似文献   
1000.
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