2,180 research outputs found

    Construction of spirocarbocycles via gold-catalyzed intramolecular dearomatization of naphthols.

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    A highly efficient, gold-catalyzed intramolecular dearomatization reaction of naphthols via 5-endo-dig cyclization is described. This facile and direct approach furnishes spirocarbocycles in excellent yields under mild conditions

    Annotating Protein Functional Residues by Coupling High-Throughput Fitness Profile and Homologous-Structure Analysis.

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    Identification and annotation of functional residues are fundamental questions in protein sequence analysis. Sequence and structure conservation provides valuable information to tackle these questions. It is, however, limited by the incomplete sampling of sequence space in natural evolution. Moreover, proteins often have multiple functions, with overlapping sequences that present challenges to accurate annotation of the exact functions of individual residues by conservation-based methods. Using the influenza A virus PB1 protein as an example, we developed a method to systematically identify and annotate functional residues. We used saturation mutagenesis and high-throughput sequencing to measure the replication capacity of single nucleotide mutations across the entire PB1 protein. After predicting protein stability upon mutations, we identified functional PB1 residues that are essential for viral replication. To further annotate the functional residues important to the canonical or noncanonical functions of viral RNA-dependent RNA polymerase (vRdRp), we performed a homologous-structure analysis with 16 different vRdRp structures. We achieved high sensitivity in annotating the known canonical polymerase functional residues. Moreover, we identified a cluster of noncanonical functional residues located in the loop region of the PB1 β-ribbon. We further demonstrated that these residues were important for PB1 protein nuclear import through the interaction with Ran-binding protein 5. In summary, we developed a systematic and sensitive method to identify and annotate functional residues that are not restrained by sequence conservation. Importantly, this method is generally applicable to other proteins about which homologous-structure information is available.ImportanceTo fully comprehend the diverse functions of a protein, it is essential to understand the functionality of individual residues. Current methods are highly dependent on evolutionary sequence conservation, which is usually limited by sampling size. Sequence conservation-based methods are further confounded by structural constraints and multifunctionality of proteins. Here we present a method that can systematically identify and annotate functional residues of a given protein. We used a high-throughput functional profiling platform to identify essential residues. Coupling it with homologous-structure comparison, we were able to annotate multiple functions of proteins. We demonstrated the method with the PB1 protein of influenza A virus and identified novel functional residues in addition to its canonical function as an RNA-dependent RNA polymerase. Not limited to virology, this method is generally applicable to other proteins that can be functionally selected and about which homologous-structure information is available

    MicroRNA-23a promotes myelination in the central nervous system.

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    Demyelinating disorders including leukodystrophies are devastating conditions that are still in need of better understanding, and both oligodendrocyte differentiation and myelin synthesis pathways are potential avenues for developing treatment. Overexpression of lamin B1 leads to leukodystrophy characterized by demyelination of the central nervous system, and microRNA-23 (miR-23) was found to suppress lamin B1 and enhance oligodendrocyte differentiation in vitro. Here, we demonstrated that miR-23a-overexpressing mice have increased myelin thickness, providing in vivo evidence that miR-23a enhances both oligodendrocyte differentiation and myelin synthesis. Using this mouse model, we explored possible miR-23a targets and revealed that the phosphatase and tensin homologue/phosphatidylinositol trisphosphate kinase/Akt/mammalian target of rapamycin pathway is modulated by miR-23a. Additionally, a long noncoding RNA, 2700046G09Rik, was identified as a miR-23a target and modulates phosphatase and tensin homologue itself in a miR-23a-dependent manner. The data presented here imply a unique role for miR-23a in the coordination of proteins and noncoding RNAs in generating and maintaining healthy myelin

    Histological features of the gastric mucosa in children with primary bile reflux gastritis

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    <p>Abstract</p> <p>Background</p> <p>Bile reflux is one of the primary factors involved in the pathogenesis of gastric mucosal lesions in patients with chronic gastritis; however, little is known about the exact histological features of bile reflux and its contributions to gastric mucosal lesions in this disease, especially in children with primary bile reflux gastritis (BRG). The aim of this study was to investigate the classic histological changes of the gastric mucosa in children with primary BRG.</p> <p>Methods</p> <p>The Bilitec 2000 was used for 24 h monitoring of gastric bile in 59 children with upper gastrointestinal symptoms. The histological characteristics of the gastric mucosa were examined and scored.</p> <p>Results</p> <p>Thirteen of the 59 patients had a helicobacter pylori infection and were excluded; therefore, 46 cases were included in this study. The positive rate of pathological duodenogastric reflux was significantly higher in patients with foveolar hyperplasia than those without foveolar hyperplasia; however, the rate was significantly lower in patients with vascular congestion than those without vascular congestion. The longest reflux time and the total percentage time of bile reflux were significantly lower in patients with vascular congestion than those without vascular congestion. A total of 9 types of histological changes were analyzed using a binary logistic regression. Foveolar hyperplasia and vascular congestion in the superficial layer became significant variables in the last step of the stepwise regression.</p> <p>Conclusions</p> <p>Foveolar hyperplasia was associated with the severity of bile reflux, suggesting that it is a histological feature of primary BRG in children, while vascular congestion may be a protective factor.</p

    Introduction to the wheelchair training's influence on the rehabilitation of patients

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    目的  通过轮椅训练提高患者掌握轮椅的技巧,保证患者乘坐轮椅时的安全,提高患者日常生活能力及社会参与能力。方法  通过轮椅基本技术动作练习、轮椅技巧动作训练、轮椅体育项目训练、社会实践检测。结果  患者轮椅训练前后对照,躯干的控制能力较前好转,ADL能力明显提高,社会参与能力增强。结论  轮椅训练可以使残疾人参与康复体育和社会活动的机会明显增加。Objective: Training to improve patient’s master of wheelchair technology to ensure the safety of patients in wheelchairs things to improve patients' daily living skills and social participation skills. Methods: By practicing basic techniques wheelchair, wheelchair technology movement training, wheelchair sports training, social practice test. Results: Wheelchair patients before and after control technology, the ability to control the trunk before it gets better, ADL ability as well as social participation improved significantly. Conclusion: Wheelchair training increased opportunities for people with disabilities to participate in the rehabilitation of sports and social activities.

    Dense 3D Facial Reconstruction from a Single Depth Image in Unconstrained Environment

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    With the increasing demands of applications in virtual reality such as 3D films, virtual Human-Machine Interactions and virtual agents, the analysis of 3D human face analysis is considered to be more and more important as a fundamental step for those virtual reality tasks. Due to information provided by an additional dimension, 3D facial reconstruction enables aforementioned tasks to be achieved with higher accuracy than those based on 2D facial analysis. The denser the 3D facial model is, the more information it could provide. However, most existing dense 3D facial reconstruction methods require complicated processing and high system cost. To this end, this paper presents a novel method that simplifies the process of dense 3D facial reconstruction by employing only one frame of depth data obtained with an off-the-shelf RGB-D sensor. The experiments showed competitive results with real world data

    Comparison of Sterile and Clean Dressing Techniques in Post-operative Surgical Wound Infection in a Chinese Healthcare Facility

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    Purpose: To investigate the effect of sterile and clean dressing techniques on wound management in a Chinese hospital, and to compare their impact on wound healing and the cost of the dressing materials with respect to postoperative surgical wounds.Methods: A total of 130 patients, comprising 70 (53.8 %) males and 60 (46.2 %) females, who had undergone surgery in The Affiliated Hospital of Changchun Traditional Chinese Medicine University, Changchun, China in 2012 – 2014 were enrolled in the study. Of these, 65 (50 %) received sterile dressings and 65 (50 %) clean dressings. A control group comprising 25 patients, 15 (60 %) males and 10 (40 %) females, who attended the clinic for change dressings only, was also included. The patients’ dressings were changed four times daily with 2x sterile and 2x clean dressings. Details of all the changes, including the nutritional status of the patients, were recorded. The patients were followed-up up to the time of their discharge.Results: Twelve (18.5 %) patients out of those who received sterile or clean dressings were found to have acquired an infection. The size of the wounds was approximately 1.8 to 32.4 cm3 (mean: 5.2 ± 6.4 cm3) in size at the start of the study and 0.6 to 4.2 cm3 at the end of the study. A significant difference was identified between the sterile and clean dressing groups at the beginning of the study (U = 72.5; p &lt; 0.12). A decrease in wound size was observed in both of these groups but was not statistically significant, while the change in wound volume, was significantly different (U = 84.5; p &lt; 0.25). When the cost of the two dressing types was compared, the sterile items were more expensive than that of the clean items; thus, sterile dressing procedure was significantly more costly than clean dressing procedure (p &lt; 0.01).Conclusion: With mounting concern regarding antimicrobial resistance and hospital-acquired infections, suitable wound dressing techniques are required to prevent infection and reduce the duration of wound healing after surgery without compromising patient safety.Keywords: Wound dressing, Postoperative, Antimicrobial resistance, Hospital acquired infection
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