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1.
The aim of the study was to determine the effect of β-glucan on the cytotoxicity and genotoxicity of polypectomized patient's fecal water (FW). Polypectomized volunteers (n = 69) were randomly assigned to consume bread with or without β-glucan, for 3 months. FW was collected at the beginning (t = 0), the 30th and 90th day and 2 wk after the intervention. Cytotoxicity and genotoxicity were estimated on Caco-2 cells, using trypan blue exclusion test and comet assay, respectively. Gastrointestinal symptoms were recorded and subjects kept a 3-day food diary at baseline and after completion. Trypan blue exclusion test revealed cell survival of approximately 87% after incubation with FW. The FW samples showed 49% genotoxicity at the baseline. Genotoxicity in the intervention group decreased during the trial reaching statistical significance on the 90th day compared to control. An increase was noticed 2 wk after the trial, but it still remained significantly lower compared to control. Group-specific analysis for β-glucan also revealed significant decrease in the genotoxicity on the 90th day compared to baseline. β-glucan ingestion in polypectomized patients significantly decreased the genotoxicity of their FW. Our findings suggest that β-glucan consumption could possibly provide protection against colon cancer development.  相似文献   
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Treatment decisions in patients with metastatic bone disease rely on accurate survival estimation. We developed the original PATHFx models using expensive, proprietary software and now seek to provide a more cost-effective solution. Using open-source machine learning software to create PATHFx version 2.0, we asked whether PATHFx 2.0 could be created using open-source methods and externally validated in two unique patient populations. The training set of a well-characterized, database records of 189 patients and the bnlearn package within R Version 3.5.1 (R Foundation for Statistical Computing), was used to establish a series of Bayesian belief network models designed to predict survival at 1, 3, 6, 12, 18, and 24 months. Each was externally validated in both a Scandinavian (n = 815 patients) and a Japanese (n = 261 patients) data set. Brier scores and receiver operating characteristic curves to assessed discriminatory ability. Decision curve analysis (DCA) evaluated whether models should be used clinically. DCA showed that the model should be used clinically at all time points in the Scandinavian data set. For the 1-month time point, DCA of the Japanese data set suggested to expect better outcomes assuming all patients will survive greater than 1 month. Brier scores for each curve demonstrate that the models are accurate at each time point. Statement of Clinical Significance: we successfully transitioned to PATHFx 2.0 using open-source software and externally validated it in two unique patient populations, which can be used as a cost-effective option to guide surgical decisions in patients with metastatic bone disease.  相似文献   
3.
Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables.  相似文献   
4.
Introduction: Pharmacological options to address the imbalance between bone resorption and accrual in osteoporosis include anti-resorptive and osteoanabolic agents. Unique biologic pathways such as the Wnt/β-catenin pathway have been targeted in the quest for new emerging therapeutic strategies.

Areas covered: This review provides an overview of existing pharmacotherapy for osteoporosis in women and explore state-of–the-art and emerging therapies to prevent bone loss, with an emphasis on the mechanism of action, indications and side effects.

Expert opinion: Bisphosphonates appear to be a reliable and cost-effective option, whereas denosumab has introduced a simpler dosing regimen and may achieve a linear increase in bone mineral density (BMD) with no plateau being observed, along with continuous anti-fracture efficacy. Abaloparatide, a parathyroid-hormone-related peptide (PTHrP)-analogue, approved by the FDA in April 2017, constitutes the first new anabolic osteoporosis drug in the US for nearly 15 years and has also proven its anti-fracture efficacy. Romosozumab, a sclerostin inhibitor, which induces bone formation and suppresses bone resorption, has also been developed and shown a significant reduction in fracture incidence; however, concerns have arisen with regard to increased cardiovascular risk.  相似文献   

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Minilaparoscopy-assisted natural orifice surgery.   总被引:5,自引:0,他引:5  
BACKGROUND AND OBJECTIVES: New technology has allowed us to perform major abdominal and pelvic surgeries with increasingly smaller instruments. The ultimate goal is surgery with no visible scars. Until current technical limitations are overcome, minilaparoscopy-assisted natural orifice surgery (MANOS) provides a solution. The aim of this study was to examine our clinical and experimental experience with MANOS. METHOD: Minilaparoscopic abdominal instruments were used together with a large vaginal port, which was used for insufflation, visual purposes, introduction of operative instruments, and specimen extraction. Minilaparoscopy-assisted intraperitoneal transgastric appendectomy was done in simulators (Lap trainer with SimuVision, Simulab Corp., Seattle, WA). RESULTS: Since 1998, we have used this technique in 100 cases including ovarian cystectomies, oophorectomies, salpingo-oophorectomies, myomectomies, appendectomies, and cholecystectomies. Some oophorectomies were performed after vaginal hysterectomy in cases where vaginal extraction was not possible. In this case series, we had only one complication, a case of postoperative fever after an ovarian cystectomy, which was diagnosed as drug-related fever. Our limited simulator experience showed that MANOS is a feasible technique for performing transgastric appendectomies. CONCLUSION: It may take several years for natural orifice surgery to become standard care. Meanwhile, MANOS could encourage and expedite this process.  相似文献   
8.
Most of the work of host defense has been carried out in mixed patient populations. It is now clear that elective preoperative surgical patients have totally different host defense capabilities as compared to posttrauma patients or those suffering from peritonitis. Specific cell-mediated immune studies need to be repeated in these 2 patient groups as well. What will contribute clinical relevance to these studies will be the means to correct the defects. If these defects or—more correctly termed—abnormalities of host defense are, indeed, important and contribute to an increased sepsis rate and mortality from sepsis in affected patients, then correcting them should reduce these complications. This hypothesis can only be tested when such means become available. The issues of most interest in the next few years will be the significance of serum albumin in host outcome, the role of immunomodulators, the involvement of cytokines in the overall process of host defense, and the use of specific nutritional support regimens targeted to the immune system.
Resumen La mayor parte del trabajo sobre los mecanismos de defensa del huésped ha sido realizada en poblaciones mixtas de pacientes. Actualmente aparece claro que los pacientes preoperatorios electivos poseen una capacidad de defensa de huésped totalmente diferente que la de los pacientes en estado posttrauma o de aquellos con peritonitis. Aparece necesario realizar estudios específicos de inmunidad celular en estos 2 grupos de pacientes; aquello que aporte pertinencia clínica en tales estudios habrá de representar medios para corregir estos defectos. Si tales defectos, mejor denominados anormalidades en las defensas del huésped, son de verdad importantes y contribuyen a mayores tasas de infección y de mortalidad por sepsis en los pacientes afectados, su corrección debe resultar en reducción de estas complicaciones. Esta hipótesis sólo puede ser puesta a prueba cuando tales medios se hallen disponibles. Los aspectos de mayor interés en los próximos años serán el significado de la albúmina sérica en la evolución final del huésped, el papel de los inmunomoduladores, la participación de las citocinas en el proceso general de defensa del huésped, y el uso de regimenes especificos de soporte nutricional dirigidos hacia el sistema inmune.

Résumé La plupart des travaux sur les mécanismes de défense ont été faits sur les populations mixtes. Il est à présent certain que les patients opérés électivement ont des mécanismes de défense préopératoire totalement différents de ceux des traumatisés ou des patients ayant une infection péritonéale. Les études immunologiques sur la médiation cellulaire spécifique méritent d'être refaites chez ces deux populations. Ce qui ressortira de ces études donnera les moyens de corriger les défauts ou plutôt les anomalies des mécanismes de défense qui contribuent à augmenter septicité et mortalité en rapport avec l'état septique. Cette hypothèse ne peut être vérifiée qu'avec ces moyens. Les questions les plus intéressantes dans les années à venir sera peut-être de connaître l'influence de l'albumine sérique sur l'évolution, le rôle des immunomodulaterus, celui des cytokinines dans le procédé global des mécanismes de défense, et celui de l'utilisation de l'alimentation spécifique pour améliorer le système immune.


Supported in part by grants from the Medical Research Council of Canada and the Fonds de recherche de Santé.  相似文献   
9.
Torsions of the spermatic cord occurring from the intrauterine period to the end of the first year of life are termed perinatal. These are divided into prenatal and postnatal torsions, depending on their occurrence in the intrauterine or postuterine period. From January 1984 to January 1996, 6 cases were identified at our institution, involving 4 prenatal and 2 postnatal extravaginal torsions of the spermatic cord. These cases are reviewed with regard to optimal therapeutic approaches for the treatment of both the affected gonad as well as the contralateral one, and whether the event occurred prenatally or postnatally. The authors also propose several clinical indications useful for obstetricians, pediatricians, urologists and nurses.  相似文献   
10.
OBJECTIVE: A prospective randomized study was conducted in order to analyze the role of fibrinolytics in the treatment of complicated parapneumonic effusion. METHODS: From 2001 to 2004, 127 consecutive patients were managed for thoracic empyema. In all cases the cause was bacterial pneumonia. Seventy patients were managed with sole tube thoracostomy (group A) and 57 with combination of tube thoracostomy and streptokinase instillation (group B). Groups were statistically compared for the age, gender, duration of symptoms, quality of pleural fluid, chest imaging, complete drainage, length of hospital stay and mortality. Multivariate analysis was used in order to define the factors that affect outcome. RESULTS: Tube thoracostomy was successful in 47 (67.1%) cases (group A), while fibrinolysis led to a favorable outcome in 50 cases (87.7%) (P<0.05). The length of stay in thoracic surgical department was significantly longer for group A (P<0.001). Mortality rate in group A was significantly higher (P<0.001). Multiple regression analysis disclosed as sole independent favorable factor for pleural drainage, the use of fibrinolysis during the course of chest tube drainage (P=0.006, odds ratio 4.29, 95% CI 1.51-12.14). CONCLUSIONS: Fibrinolytic agents are a useful adjunct in the management of complicated parapneumonic effusions. Intrapleural fibrinolytics, if used early in the fibrinopurulent stage of a parapneumonic effusion, decrease the rate of surgical interventions (VATS or open decortcation) and the length of hospital stay with minor associated morbidity.  相似文献   
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