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41.
42.
Jose M. Enríquez-Navascues Araceli RodríguezCarlos Placer Yolanda SaraleguiAlberto Carrillo 《Cirugía espa?ola》2013
Purpose
There are some circumstances in which the descending colon does not reach the pelvis to complete a colorectal anastomosis without tension. Re-establishing intestinal continuity by interposing small bowel as a bridge between the colon and the rectum could be an acceptable surgical alternative.Methods
We describe the interposition of one or two segments of small bowel as a way of restoring continuity of the colon and rectum in three patients in whom it was not possible to perform a colorectal anastomosis without tension due to ischaemic colon, synchronous cancer or difficulty in accessing the supramesocolic space, respectively.Results
Intestinal continuity was re-established in all patients with no significant morbidity and good intestinal function.Conclusion
The interposition of small bowel segments between the colon and the rectum should be considered a valid surgical option when it is not possible to achieve a well-perfused, tension-free pelvic colorectal anastomosis. 相似文献43.
Green TN Archary M Gordon ML Padayachi N Lie Y Anton ED Reeves JD Grobler A Bobat R Coovadia H Ndung'u T 《AIDS research and human retroviruses》2012,28(4):324-332
HIV-1 drug resistance monitoring in resource-poor settings is crucial due to limited drug alternatives. Recent reports of the increased prevalence of CXCR4 usage in subtype C infections may have implications for CCR5 antagonists in therapy. We investigated the prevalence of drug resistance mutations and CXCR4 coreceptor utilization of viruses from HIV-1 subtype C-infected children. Fifty-one children with virological failure during highly active antiretroviral therapy (HAART) and 43 HAART-naive children were recruited. Drug resistance genotyping and coreceptor utilization assessment by phenotypic and genotypic methods were performed. At least one significant drug resistance mutation was present in 85.4% of HAART-failing children. Thymidine analogue mutations (TAMs) were detected in 58.5% of HAART-failing children and 39.0% had ≥3 TAMs. CXCR4 (X4) or dual (R5X4)/mixed (R5, X4) (D/M)-tropic viruses were found in 54.3% of HAART-failing and 9.4% of HAART-naive children (p<0.0001); however, the HAART-failing children were significantly older (p<0.0001). In multivariate logistic regression, significant predictors of CXCR4 usage included antiretroviral treatment, older age, and lower percent CD4(+) T cell counts. The majority of genotypic prediction tools had low sensitivity (≤65.0%) and high specificity (≥87.5%) for predicting CXCR4 usage. Extensive drug resistance, including the high percentage of TAMs found, may compromise future drug choices for children, highlighting the need for improved treatment monitoring and adherence counseling. Additionally, the increased prevalence of X4/D/M viruses in HAART-failing children suggests limited use of CCR5 antagonists in salvage therapy. Enhanced genotypic prediction tools are needed as current tools are not sensitive enough for predicting CXCR4 usage. 相似文献
44.
45.
Lars E. Hagander Christopher D. Hughes Katherine Nash Karan Ganjawalla Allison Linden Yolanda Martins Kathleen M. Casey John G. Meara 《World journal of surgery》2013,37(1):14-23
Background
The critical shortage of surgeons in many low- and middle-income countries (LMICs) prevents adequate responses to surgical needs, but the factors that affect surgeon migration have remained incompletely understood. The goal of this study was to examine the importance of personal, professional, and infrastructural factors on surgeon migration from LMICs to the United States. We hypothesized that the main drivers of surgeon migration can be addressed by providing adequate domestic surgical infrastructure, surgical training programs, and viable surgical career paths.Methods
We conducted an internet-based nationwide survey of surgeons living in the US who originated from LMICs.Results
66 surgeons completed the survey. The most influential factors for primary migration were related to professional reasons (p ≤ 0.001). Nonprofessional factors, such as concern for remuneration, family, and security were significantly less important for the initial migration decisions, but adopted a more substantial role in deciding whether or not to return after training in the United States. Migration to the United States was initially considered temporary (44 %), and a majority of the surveyed surgeons have returned to their source countries in some capacity (56 %), often on multiple occasions (80 %), to contribute to clinical work, research, and education.Conclusions
This study suggests that surgically oriented medical graduates from LMICs migrate primarily for professional reasons. Initiatives to improve specialist education and surgical infrastructure in LMICs have the potential to promote retention of the surgical workforce. There may be formal ways for LMICs to gain from the international pool of relocated surgeons. 相似文献46.
47.
Vianey de la Rosa-Lugo Myrna Déciga-Campos María Yolanda Ríos Diana Saray Navarrete-Herrera Francisco Javier López-Muñoz 《Drug development research》2020,81(8):969-977
The present work aimed to determine the safety parameters of two new alkamides, affinin and hexahydroaffinin, with antinociceptive activity. To predict the preliminary acute toxicity, we used the acute and subchronic toxicity (50 mg/kg, orally [po]) in Swiss Webster mice. Genotoxicity assayed via analysis of cell micronuclei of the femoral bone marrow in mice; at the same time, metabolic parameters determined from peripheral blood samples. Furthermore, to discard the neuropharmacological effects, we assessed the ambulatory activity in mice to determine the possible effects in the central nervous system. Finally, we used capsaicin as a positive control of alkamides. According to our results, hexahydroaffinin (LD50 ≥ 5,000 mg/kg, po) is significantly less noxious than affinin (LD50 = 1,442.2 mg/kg, po) or capsaicin (LD50 = 489.9 mg/kg, po). In subchronic administration, we did not observe any changes in hematological or biochemical parameters in any compound analyzed from peripheral blood samples. Finally, the data from the genotoxicity assay showed micronuclei formation in 28%, 5%, and 3% of mice in the capsaicin, affinin, and hexahydroaffinin groups, respectively. With the results obtained in the present investigation, we suggest that affinin and hexahydroaffinin are not only useful candidates for possible new drugs but also safe compounds. 相似文献
48.
Marc Martí-Pastor Angels Pont Mónica Ávila Olatz Garin Gemma Vilagut Carlos G. Forero Yolanda Pardo Ricard Tresserras Antonia Medina-Bustos Oriol Garcia-Codina Juan Cabasés Luis Rajmil Jordi Alonso Montse Ferrer 《Population health metrics》2018,16(1):14
Background
The EQ-5D has been frequently used in national health surveys. This study is a head-to-head comparison to assess how expanding the number of levels from three (EQ-5D-3L) to five in the new EQ-5D-5L version has improved its distribution, discriminatory power, and validity in the general population.Methods
A representative sample (N?=?7554) from the Catalan Health Interview Survey 2011–2012, aged ≥18, answered both EQ-5D versions, and we evaluated the response redistribution and inconsistencies between them. To assess validity of this redistribution, we calculated the mean of the Visual Analogue Scale (VAS), which measures perceived health. The discriminatory power was examined with Shannon Indices, calculated for each dimension separately. Spanish preference value sets were applied to obtain utility indices, examining their distribution with statistics of central tendency and dispersion. We estimated the proportion of individuals reporting the best health state in EQ-5D-5L and EQ-5D-3L within groups of specific chronic conditions and their VAS mean.Results
A very small reduction in the percentage of individuals with the best health state was observed, from 61.8% in EQ-5D-3L to 60.8% in EQ-5D-5L. In contrast, a large proportion of individuals reporting extreme problems in the 3 L version moved to severe problems (level 4) in the 5 L version, particularly for pain/discomfort (75.5%) and anxiety/depression (66.4%). The average proportion of inconsistencies was 0.9%. The pattern of the perceived health VAS mean confirmed the hypothesis established a priori, supporting the validity of the observed redistribution. Shannon index showed that absolute informativity was higher in the 5 L version for all dimensions. The means (SD) of the Spanish EQ-5D-3L and EQ-5D-5L indices were 0.87 (0.25) and 0.89 (0.22). The proportion of individuals with the best health state within each specific chronic condition was very similar, regardless of the EQ-5D version (≤?30% in half of the 28 chronic conditions).Conclusion
Although the proportion of individuals with the best possible health state is still very high, our findings support that the increase of levels provided by the EQ-5D-5L contributed to the validity and discriminatory power of this new version to measure health in general population, as in the national health surveys.49.
Pau Rocas Yolanda Fernández Natalia García-Aranda Laia Foradada Pilar Calvo Pablo Avilés María José Guillén Simó Schwartz Josep Rocas Fernando Albericio Ibane Abasolo 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(2):257-267
Glutathione degradable polyurethane-polyurea nanoparticles (PUUa NP) with a disulfide-rich multiwalled structure and a cyclic RGD peptide as a targeting moiety were synthesized, incorporating a very lipophilic chemotherapeutic drug named Plitidepsin. In vitro studies indicated that encapsulated drug maintained and even improved its cytotoxic activity while in vivo toxicity studies revealed that the maximum tolerated dose (MTD) of Plitidepsin could be increased three-fold after encapsulation. We also found that pharmacokinetic parameters such as maximum concentration (Cmax), area under the curve (AUC) and plasma half-life were significantly improved for Plitidepsin loaded in PUUa NP. Moreover, biodistribution assays in mice showed that RGD-decorated PUUa NP accumulate less in spleen and liver than non-targeted conjugates, suggesting that RGD-decorated nanoparticles avoid sequestration by macrophages from the reticuloendothelial system. Overall, our results indicate that polyurethane-polyurea nanoparticles represent a very valuable nanoplatform for the delivery of lipophilic drugs by improving their toxicological, pharmacokinetic and whole-body biodistribution profiles. 相似文献
50.
Di Stefano S Casquero E Bustamante R Gualis J Carrascal Y Bustamante J Fulquet E Florez S Echevarria JR Fiz L 《The Tohoku journal of experimental medicine》2007,213(1):63-69
All types of cardiac surgery involve considerable injury to the myocardium. However, it is difficult to differentiate, in the immediate post-operative state, between ischemic alterations associated with the cardiac surgery itself and the pathological alterations of a peri-operative myocardial infarction. The diagnosis of damaged myocardium, classically performed with the enzymatic markers creatine kinase (CK) and its muscle fraction (CK-MB), has become more precise with the option of measuring cardiac troponins T and I. We measured these markers in 58 patients undergoing elective cardiac surgery with extra-corporeal circulation (ECC). The patients included 37 cases undergoing valve surgery, 14 for coronary revascularization, 6 for mixed procedures, and 1 for closure of an inter-atrial communication. The markers were measured in plasma at baseline (at anesthesia initiation), 5 min post-ECC commencement, following aorta de-clamping, during the surgical closure, and 6, 18 and 42 hrs after surgery. All the markers were increased significantly relative to the baseline values. Troponin I, CK and CK-MB values peaked between 6 and 18 hrs after surgery, troponin T between 18 and 42 hrs, and myoglobin at the surgical closure. The values of all markers were higher in patients undergoing coronary surgery compared to those in patients undergoing valve surgery. In the evaluation of myocardial damage after surgery, the measurement of classical markers such as CK and myoglobin remain valid, but other markers such as troponins provide significant additional diagnostic benefit and, thus, need to be included in the routine biochemical measurements for monitoring myocardial damage associated with the surgical procedure. 相似文献