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ES Charlson JM Diamond K Bittinger AS Fitzgerald A Yadav AR Haas FD Bushman RG Collman 《American journal of respiratory and critical care medicine》2012,186(6):536-545
Rationale: Long-term survival after lung transplantation is limited by infectious complications and by bronchiolitis obliterans syndrome (BOS), a form of chronic rejection linked in part to microbial triggers. Objectives: To define microbial populations in the respiratory tract of transplant patients comprehensively using unbiased high-density sequencing. Methods: Lung was sampled by bronchoalveolar lavage (BAL) and upper respiratory tract by oropharyngeal wash (OW). Bacterial 16S rDNA and fungal internal transcribed spacer sequencing was used to profile organisms present. Outlier analysis plots defining taxa enriched in lung relative to OW were used to identify bacteria enriched in lung against a background of oropharyngeal carryover. Measurements and Main Results: Lung transplant recipients had higher bacterial burden in BAL than control subjects, frequent appearance of dominant organisms, greater distance between communities in BAL and OW indicating more distinct populations, and decreased respiratory tract microbial richness and diversity. Fungal populations were typically dominated by Candida in both sites or by Aspergillus in BAL but not OW. 16S outlier analysis identified lung-enriched taxa indicating bacteria replicating in the lower respiratory tract. In some cases this confirmed respiratory cultures but in others revealed enrichment by anaerobic organisms or mixed outgrowth of upper respiratory flora and provided quantitative data on relative abundances of bacteria found by culture. Conclusions: Respiratory tract microbial communities in lung transplant recipients differ in structure and composition from healthy subjects. Outlier analysis can identify specific bacteria replicating in lung. These findings provide novel approaches to address the relationship between microbial communities and transplant outcome and aid in assessing lung infections. 相似文献
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Gunjan Arora Manavi Yadav Rashmi Gaur Radhika Gupta Pooja Rana Priya Yadav Rakesh Kumar Sharma 《RSC advances》2020,10(33):19390
In the present report, an environmentally benign magnetically recoverable nickel(ii)-based nanoreactor as a heterogeneous catalyst has been developed via a template free approach. The catalytic performance of the synthesized catalyst is assessed in the confined oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides under aerobic conditions. The salient features of our protocol include oxidant- and ligand-free conditions, use of water as a green solvent, room temperature and formation of nitrogen and water as the only by-products. Moreover, a broad range of functional groups are tolerated well and provide the corresponding diaryl sulfides in moderate to good yields. Moreover, the heterogeneous nature of the catalyst permits facile magnetic recovery and reusability for up to seven runs, making the present protocol highly desirable from industrial and environmental standpoints.An environmentally benign nickel(ii)-based magnetic nanoreactor has been developed for oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides in water at room temperature. 相似文献
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V. Manikandan Ali Mirzaei S. Sikarwar B. C. Yadav S. Vigneselvan A. Vanitha J. Chandrasekaran 《RSC advances》2020,10(23):13611
A sensor displaying a rapid response and high sensitivity was developed by following a simple route. Ionic defects in this sensor were explored using X-ray diffraction analysis. In general, such defects arise from a mismatch of ionic radii, which actually improves the sensing performance. SEM and TEM images of the currently produced particles demonstrated negligible agglomeration, which greatly enhanced the flow of water molecules through the particles. The current sensor showed a rapid response to changes in humidity. Its sensing performance was classified into three different ranges of humidity. Of these humidity ranges, the sensor showed the highest sensitivity (8.84 MΩ per %RH) at low relative humidity (10–20% RH). Furthermore, the sensitivity fall off as the RH was increased from 20 to 99%. The sensor showed a rapid response time of 20 s. Also, the sensor showed 92.98% reproducibility and few effects of aging.A sensor displaying a rapid response and high sensitivity was developed by following a simple route. 相似文献
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A simple synthetic strategy has been developed for the synthesis of 2- and 1-alkyl/aryl/dialkylaminoquinolines and isoquinolines from the easily available quinoline and isoquinoline-N-oxides, different amines, triflic anhydride as activating agent and acetonitrile as solvent in a one-pot reaction under metal-free conditions at 0 °C to room temperature.A synthetic strategy has been developed for synthesis of 2 and 1-aminoquinolines and isoquinolines from quinoline and isoquinoline-N-oxides, amines and triflic anhydride in acetonitrile at 0 °C to room temperature. 相似文献
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Prabha Yadav 《Indian Journal of Plastic Surgery》2013,46(2):275-282
Whatever is excisable, is reconstructable! “You excise, we will reconstruct” are the confident words of reconstructive surgeons today. Reconstruction with multiple flaps has become routine. Radial artery (FRAF), Antero lateral thigh (ALT) and Fibula osteo cutaneous flap (FFOCF) are three most popular free flaps which can reconstruct any defect with excellent asthetics and performance. Radial Artery provides thin, pliable innervated skin; ALT large amount of skin & bulk; and FFOCF strong 22 to 25 centimetres of bone and reliable skin paddle. Free flap survival has gone to 98% in most of the renouned institutes and is an established escalator in management of defects.KEY WORDS: Free flap, head and neck, reconstruction 相似文献
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