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In epithelial tissue, cell-matrix and cell-cell adhesive interactions have important roles in the normal organization and stabilization of the cell layer. The malignant conversion of epithelial cells involves alterations in the expression and function of these adhesion systems that enable a switch to a migratory phenotype in tumor invasion and metastasis. Fascin is an actin-crosslinking protein that is found in the core actin bundles of cell-surface spikes and projections that are implicated in cell motility. We demonstrate that fascin is not detectable in normal colonic epithelium, but is dramatically up-regulated in colorectal adenocarcinoma. To test the hypothesis that fascin could participate in tumor invasive behavior, we developed a cell culture model to examine the effect of fascin expression on the adhesive interactions, invasiveness, and differentiation of colonic epithelial cells. We report marked effects on the organization of cell-surface protrusions, actin cytoskeleton, and focal adhesions in the absence of alterations in the protein levels of the major components of these structures. These effects correlate with alterations in cell movements on two-dimensional matrix, and increased invasiveness in three-dimensional matrix. The cells also show increased proliferation and decreased capacity for normal glandular differentiation in collagen gels. We propose that up-regulation of fascin, by promoting the formation of protrusive, actin-based, cell-motility structures, could be a significant component in the acquisition of invasive phenotype in colonic carcinoma.  相似文献   
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Absence of transforming growth factor-beta (TGF-beta) signaling to T cells in mice results in an increase in T cell numbers, an activated CD44 high, CD69-, CD25- T cell phenotype and a T cell-mediated injury to many organs. It is not known if such T cell activation in the absence of TGF-beta signaling is spontaneous or due to aberrant T cell responses to a physiological stimulus. We used adoptive transfer of CD8+ T cells from mice double transgenic for the OT-1 TCR and the TGF-beta1-dominant negative transgene [OT-dominant-negative receptor (DNR)] to investigate the role of TGF-beta in regulating CD8+ T cell activation in vivo. The activation and expansion of single-transgenic OT and double-transgenic OT-DNR cells to oral antigens, high-affinity and low-affinity peptides were indistinguishable. Activation with high-affinity peptide and CFA however resulted in greater expansion of OT-DNR cells in comparison to OT cells. Low-affinity peptide and adjuvant did not result in OT cell activation or expansion but results in up-regulation of CD44 on OT-DNR cells. These data show that TGF-beta functions in vivo to limit the scale of CD8+ T cell expansion after high-affinity peptide-MHC interactions. TGF-beta also limits T cell activation to the highest affinity peptide-MHC interactions. The increase in T cell number and activation present in TGF-beta-deficient and TGF-beta DNR-expressing mice may be due to the loss of these two phenomena.  相似文献   
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The genus Mentha comprises several aromatic species, which are cultivated world‐over due to their distinct aroma and commercial value. In addition to traditional food flavoring uses, Mentha are well recognized for their folk medicinal uses, especially to treat cold, fever, and digestive and cardiovascular disorders. A number of biological activities such as antioxidant, antimicrobial, biopesticidal, antitumor, anticancer, antiviral, antiallergic, antiinflammatory, antihypertensive, and urease inhibitory activity have been ascribed to Mentha. The traditional pharmacological attributes of Mentha herbs can be linked to the occurrence of bioactive phytochemicals such as terpenoids, alcohols, rosmarinic acid, and antioxidant phenolics among others. A rich source of bioactives, different species of Mentha, can be explored as a promising candidate for the development of nutra‐pharmaceuticals. This review covers the nutritional, phytochemical, and traditional medicinal aspects and multiple biological activities of some commonly available species of Mentha so as to explore their potential applications for nutra‐pharmaceutical and cosmo‐nutraceutical industry. Detailed chemical profile and pharmaceutical attributes of various Mentha essential oils are also covered. Moreover, based on computational analysis, quantitative chemical component–antioxidant activity relationship model is reviewed to predict and correlate structure–activity relationship of potential bioactives in selected Mentha essential oils leading to discovery and developmenmt of novel natural drugs.  相似文献   
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Objective: To evaluate the effectiveness of Judet''s quadricepsplasty for treatment of knee contractures and to identify the effect of local infiltration of epinephrine on blood loss associated with this procedure. Methods: A retrospective cohort study was conducted in which all cases of knee contractures managed with Judet''s quadricepsplasty from 1st January 2009 to 31st December 2013 were included and were divided into two groups. The epinephrine group included patients who were infiltrated with diluted epinephrine (1:400,000) along with xylocaine, around the operative field 15 min prior to the incision time, while the control group did not receive any infiltration. Judet''s outcome, blood loss, drop in hemoglobin and required blood transfusion were noted for all patients and compared between both groups. Results: Most common preceding pathology identified for the development of knee contractures was periarticular fracture while ilizarov application was the most common etiology. Both groups were found similar in all preoperative characteristics except preoperative flexion contracture (p=0.02). All functional outcome measures including Judet''s outcome were similar in both groups. In contrast, duration of surgery (p=0.01), blood loss (p=0.02), drop in hemoglobin (p=0.01) and number of transfusions (p=0.03) were significantly reduced in epinephrine group. Conclusion: Judet''s quadricepsplasty is a useful procedure to increase the range of motion of rigid knees and local infiltration of epinephrine is effective in decreasing the amount of subsequent blood loss and transfusion requirements.  相似文献   
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Background:Chronic kidney disease (CKD)-associated pruritus (CKD-aP) contributes to poor quality of life, including reduced sleep quality and poor sleep quality is a source of patient stress and is linked to lower health-related quality of life. This study aimed to investigate the effectiveness of zolpidem 10 mg and acupressure therapy on foot acupoints to improve the sleep quality and overall quality of life among hemodialysis patients suffering from CKD-aP.Method:A multicenter, prospective, randomized, parallel-design, open label interventional study to estimate the effectiveness of zolpidem (10 mg) oral tablets versus acupressure on sleep quality and quality of life in patients with CKD-aP on hemodialysis. A total of 58 hemodialysis patients having sleep disturbance due to CKD-aP completed the entire 8-week follow-up. The patients were divided into a control (acupressure) group of 28 patients and an intervention (zolpidem) group of 30 patients.Results:A total of 58 patients having CKD-aP and sleep disturbance were recruited. In the control group there was a reduction in the PSQI score with a mean ± SD from 12.28 ± 3.59 to 9.25 ± 3.99, while in the intervention group the reduction in PSQI score with a mean ± SD was from 14.73 ± 4.14 to 10.03 ± 4.04 from baseline to endpoint. However, the EQ5D index score and EQ-visual analogue scale (VAS) at baseline for the control group with a mean ± SD was 0.49 ± 0.30 and 50.17 ± 8.65, respectively, while for the intervention group the values were 0.62 ± 0.26 and 47.17 ± 5.82, respectively. The mean EQ5D index score in the control group improved from 0.49 ± 0.30 to 0.53 ± 0.30, but in the intervention group there was no statistical improvement in mean EQ5D index score from 0.62 ± 0.26 to 0.62 ± 0.27 from baseline to week 8. The EQ 5D improved in both groups and the EQ-VAS score was 2.67 points higher at week 8 as compared to baseline in the control group, while in the intervention group the score was 3.33 points higher at week 8 as compared to baseline. Comparing with baseline, the PSQI scores were significantly reduced after week 4 and week 8 (P =  < .001). Furthermore, at the end of the study, the PSQI scores were significantly higher in the control as compared to the intervention group (P = .012).Conclusion:An improvement in sleep quality and quality of life among CKD-aP patients on hemodialysis has been observed in both the control and intervention groups. Zolpidem and acupressure safety profiling showed no severe adverse effect other that drowsiness, nausea and daytime sleeping already reported in literature of zolpidem.  相似文献   
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Background

The COVID-19 pandemic has impacted numerous facets of healthcare workers’ lives. There have also been significant changes in Gastroenterology (GI) fellowship training as a result of the challenges presented by the pandemic.

Aims

We conducted a national survey of Gastroenterology fellows to evaluate fellows’ perceptions, changes in clinical duties, and education during the pandemic.

Methods

A survey was sent to Gastroenterology (GI) fellows in the USA. Information regarding redeployment, fellow restriction in endoscopy, outpatient clinics and inpatient consults, impact on educational activities, and available wellness resources was obtained. Fellows’ level of agreement with adjustments to clinical duties was also assessed.

Results

One hundred and seventy-seven Gastroenterology fellows responded, and 29.4% were redeployed to non-GI services during the pandemic. COVID-19 impacted all aspects of GI fellowship training in the USA (endoscopy, outpatient clinics, inpatient consults, educational activities). Fellows’ level of agreement in changes to various aspects of fellowship varied. 72.5% of respondents reported that their programs provided them with increased wellness resources to cope with the additional stress during the pandemic. For respondents with children, 17.6% reported no support with childcare.

Conclusions

Our results show that the COVID-19 pandemic has impacted GI fellowship training in the USA in multiple domains, including gastrointestinal endoscopy, inpatient consults, outpatient clinics, and educational conferences. Our study highlights the importance of considering and incorporating fellows’ viewpoints, as changes are made in response to the ongoing pandemic.

  相似文献   
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An increased consumption of energy-dense, nutrient-poor food and beverages as a result of a changing obesogenic environment contributes substantially to the increasing prevalence of childhood overweight and obesity. This paper reviews the nature and extent of food industry influences which expose children to commercial influences and thus might affect unhealthy dietary behaviour and finally contributes to obesity. A systematic search of nine electronic databases (including PubMed, PsycINFO, EconLit) and reference lists of original studies and reviews using key search terms identified 1900 articles. Of these only thirty-six articles met the inclusion and quality criteria. A narrative synthesis of the reviewed studies revealed six key obesogenic environments by which the food industry possibly influences obesity-related dietary behaviours in young children. These were schools, retailers, mass media “television”, mass media “internet”, home and promotional campaigns. Identifying these obesogenic environments is critical for monitoring and controlling the food industry, the development of effective environmental-level interventions to prevent childhood overweight and obesity and to identify knowledge gaps to be addressed in future research to support informed decisions of policy makers.  相似文献   
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