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1.
The virD operon of Agrobacterium tumefaciens Ti plasmid encodes a DNA-relaxing enzyme. 总被引:15,自引:3,他引:12 下载免费PDF全文
J Ghai A Das 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(9):3109-3113
The virD locus of Agrobacterium tumefaciens Ti plasmid encodes functions necessary for endonucleolytic cleavage of transferred DNA (T-DNA) prior to its transfer to plant cells. For the overproduction of the VIRD proteins in Escherichia coli a tac-virD operon fusion was constructed. A significant increase in the accumulation of VIRD proteins was observed in a lon protease-deficient E. coli host. The presence of an overlapping open reading frame (ORF) upstream of the VIRD1 coding sequence had a negative effect on VIRD1 production. A preparation containing VIRD proteins catalyzes the conversion of supercoiled (form I) DNA to relaxed (form IV) DNA. This activity is similar to that of a DNA topoisomerase. The relaxation activity lacks DNA sequence specificity, requires magnesium ion, and has no requirement for an energy source. Studies with plasmids that had lost defined DNA segments encompassing various virD coding regions showed that VIRD1 is the DNA-relaxing enzyme. In a density gradient centrifugation experiment, the DNA-relaxing activity sedimented as a 21-kDa polypeptide. Earlier studies of Jayaswal et al. [Jayaswal, R., Veluthambi, K., Gelvin, S. & Slightom, J. (1987) (J. Bacteriol. 169, 5035-5045] have shown that in E. coli VIRD2 alone is not sufficient for endonucleolytic cleavage of T-DNA and requires VIRD1 for its activity. 相似文献
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Ria R. Ghai Ann Carpenter Amanda Y. Liew Krystalyn B. Martin Meghan K. Herring Susan I. Gerber Aron J. Hall Jonathan M. Sleeman Sophie VonDobschuetz Casey Barton Behravesh 《Emerging infectious diseases》2021,27(4):1015
The ongoing global pandemic caused by coronavirus disease has once again demonstrated the role of the family Coronaviridae in causing human disease outbreaks. Because severe acute respiratory syndrome coronavirus 2 was first detected in December 2019, information on its tropism, host range, and clinical manifestations in animals is limited. Given the limited information, data from other coronaviruses might be useful for informing scientific inquiry, risk assessment, and decision-making. We reviewed endemic and emerging infections of alphacoronaviruses and betacoronaviruses in wildlife, livestock, and companion animals and provide information on the receptor use, known hosts, and clinical signs associated with each host for 15 coronaviruses detected in humans and animals. This information can be used to guide implementation of a One Health approach that involves human health, animal health, environmental, and other relevant partners in developing strategies for preparedness, response, and control to current and future coronavirus disease threats. 相似文献
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Nathan Perlis Antonio Finelli Mike Lovas Alejandro Berlin Janet Papadakos Sangeet Ghai Vasiliki Bakas Shabbir Alibhai Odelia Lee Adam Badzynski David Wiljer Alexis Lund Amelia Di Meo Joseph Cafazzo Masoom Haider 《Canadian Urological Association journal》2021,15(4):108
IntroductionAs we progress to an era when patient autonomy and shared decision-making are highly valued, there is a need to also have effective patient-centered communication tools. Radiology reports are designed for clinicians and can be very technical and difficult for patients to understand. It is important for patients to understand their magnetic resonance imaging (MRI) report in order to make an informed treatment decision with their physician. Therefore, we aimed to create a patient-centered prostate MRI report to give our patients a better understanding of their clinical condition.MethodsA prototype patient-centered radiology report (PACERR) was created by identifying items to include based on opinions sought from a group of patients undergoing prostate MRI and medical experts. Data was collected in semi-structured interviews using a salient belief question. A prototype PACERR was created in collaboration with human factors engineering and design, medical imaging, biomedical informatics, and cancer patient education groups.ResultsFifteen patients and eight experts from urology, radiation oncology, radiology, and nursing participated in this study. Patients were particularly interested to have a report with laymen terms, concise language, contextualization of values, definitions of medical terms, and next course of action. Everyone believed the report should include the risk of MRI findings actually being cancer in the subsequent biopsy.ConclusionsA prostate MRI PACERR has been developed to communicate the most important findings relevant to decision-making in prostate cancer using patient-oriented design principles. The ability of this tool to improve patient knowledge and communication will be explored. 相似文献
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Sandeep Randhawa Puneet Ghai Sunil Bhoyrul 《Surgery for obesity and related diseases》2013,9(2):296-299
BackgroundLaparoscopic adjustable gastric banding surgery is one of the most popular procedures for patients with morbid obesity. Although it is one of the least invasive surgical treatments for obesity, the most common reasons for reoperation are complications arising from the subcutaneous reservoir (port) used to adjust the band. Mesh fixation of the port, in which the port is sutured to a piece of mesh and then placed without anchoring sutures onto the fascia is a method of securing the port. The purpose of the present study was to review the experience of a single surgeon (S.B.) with mesh fixation in >500 patients during a 4-year period and to assess the safety and efficacy of this technique in private practice in United States.MethodsA total of 564 patients underwent laparoscopic gastric banding during a 4-year period from January 2007 to January 2011. During these operations, the subcutaneous port was affixed to the fascia by suturing the port to a small piece of polypropylene mesh and then placing the port onto the fascia without any additional anchoring sutures or staples.ResultsOf 564 patients, only 2 required reoperation to reposition the subcutaneous port, for a .3% port flip rate. We also report the findings during elective reoperation for plastic surgery or revision surgery.ConclusionMesh fixation of the subcutaneous port is simple, inexpensive, and highly effective and has an extremely low complication rate. 相似文献
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A. W. Postema T. M. De Reijke O. Ukimura W. Van den Bos A. R. Azzouzi E. Barret D. Baumunk A. Blana A. Bossi M. Brausi J. A. Coleman S. Crouzet J. Dominguez-Escrig S. Eggener R. Ganzer S. Ghai I. S. Gill R. T. Gupta T. O. Henkel M. Hohenfellner J. S. Jones F. Kahmann C. Kastner K. U. Köhrmann G. Kovacs R. Miano R. J. van Moorselaar N. Mottet L. Osorio B. R. Pieters T. J. Polascik A. R. Rastinehad G. Salomon R. Sanchez-Salas M. Schostak L. Sentker K. J. Tay I. M. Varkarakis A. Villers J. Walz J. J. De la Rosette 《World journal of urology》2016,34(10):1373-1382
Purpose
To reach standardized terminology in focal therapy (FT) for prostate cancer (PCa).Methods
A four-stage modified Delphi consensus project was undertaken among a panel of international experts in the field of FT for PCa. Data on terminology in FT was collected from the panel by three rounds of online questionnaires. During a face-to-face meeting on June 21, 2015, attended by 38 experts, all data from the online rounds were reviewed and recommendations for definitions were formulated.Results
Consensus was attained on 23 of 27 topics; Targeted FT was defined as a lesion-based treatment strategy, treating all identified significant cancer foci; FT was generically defined as an anatomy-based (zonal) treatment strategy. Treatment failure due to the ablative energy inadequately destroying treated tissue is defined as ablation failure. In targeting failure the energy is not adequately applied to the tumor spatially and selection failure occurs when a patient was wrongfully selected for FT. No definition of biochemical recurrence can be recommended based on the current data. Important definitions for outcome measures are potency (minimum IIEF-5 score of 21), incontinence (new need for pads or leakage) and deterioration in urinary function (increase in IPSS >5 points). No agreement on the best quality of life tool was established, but UCLA-EPIC and EORTC-QLQ-30 were most commonly supported by the experts. A complete overview of statements is presented in the text.Conclusion
Focal therapy is an emerging field of PCa therapeutics. Standardization of definitions helps to create comparable research results and facilitate clear communication in clinical practice.10.