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1.
Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo. 相似文献
2.
Neuropeptide Y Attenuates Stress‐Induced Bone Loss Through Suppression of Noradrenaline Circuits 下载免费PDF全文
PA Baldock S Lin L Zhang T Karl Y Shi F Driessler A Zengin B Hörmer NJ Lee IPL Wong EJD Lin RF Enriquez B Stehrer MJ During E Yulyaningsih S Zolotukhin ST Ruohonen E Savontaus A Sainsbury H Herzog 《Journal of bone and mineral research》2014,29(10):2238-2249
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research. 相似文献
3.
ST Hornby FD McDermott M Coleman Z Ahmed J Bunni D Bunting M Elshaer V Evans A Kimble M Kostalas G Page J Singh L Szczebiot S Wienand-Barnett A Wilkins O Williams P Newell Severn Peninsula Audit Research Collaborative 《Annals of the Royal College of Surgeons of England》2015,97(2):115-119
Background
Laparoscopic hernia repair is used widely for the repair of incisional hernias. Few case studies have focussed on purely ‘incisional’ hernias. This multicentre series represents a collaborative effort and employed statistical analyses to provide insight into the factors predisposing to recurrence of incisional hernia after laparoscopic repair. A specific hypothesis (ie, laterality of hernias as well as proximity to the xyphoid process and pubic symphysis predisposes to recurrence) was also tested.Methods
This was a retrospective study of all laparoscopic incisional hernias undertaken in six centres from 1 January 2004 to 31 December 2010. It comprised a comprehensive review of case notes and a follow-up using a structured telephone questionnaire. Patient demographics, previous medical/surgical history, surgical procedure, postoperative recovery, and perceived effect on quality of life were recorded. Repairs undertaken for primary ventral hernias were excluded. A logistic regression analysis was then fitted with recurrence as the primary outcome.Results
A total of 186 cases (91 females) were identified. Median follow-up was 42 months. Telephone interviews were answered by 115/186 (62%) of subjects. Logistic regression analyses suggested that only female sex (odds ratio (OR) 3.53; 95% confidence interval (CI) 1.39–8.97) and diabetes mellitus (3.54; 1–12.56) significantly increased the risk of recurrence. Position of the defect had no statistical effect.Conclusions
These data suggest an increased risk of recurrence after laparoscopic incisional hernia repair in females and subjects with diabetes mellitus. These data will help inform surgeons and patients when considering laparoscopic management of incisional hernias. We recommend a centrally hosted, prospectively maintained national/international database to carry out additional research. 相似文献4.
Transfer of 15-lipoxygenase gene into rabbit iliac arteries results in the appearance of oxidation-specific lipid-protein adducts characteristic of oxidized low density lipoprotein. 下载免费PDF全文
S Yl-Herttuala J Luoma H Viita T Hiltunen T Sisto T Nikkari 《The Journal of clinical investigation》1995,95(6):2692-2698
Oxidized low density lipoprotein (LDL) possesses several atherogenic properties. The mechanisms by which LDL becomes oxidized in vivo remain unknown, but previous studies have suggested that 15-lipoxygenase may be one of the factors involved in the initiation of LDL oxidation in the arterial wall. 3 wk after a retrovirus-mediated 15-lipoxygenase gene transfer into iliac arteries of normocholesterolemic rabbits there was a threefold increase in 15-lipoxygenase activity but no signs of LDL oxidation. However, when animals were made moderately hypercholesterolemic by feeding a 0.13% cholesterol diet for 2-3 wk starting from day 4 after the gene transfer, oxidation-specific lipid-protein adducts characteristic of oxidized LDL were detected in 15-lipoxygenase-transduced arteries. Control experiments in which contralateral iliac arteries were transduced with beta-galactosidase-containing retroviruses showed only occasional signs of the presence of oxidation-specific adducts. The results support the hypothesis that products derived from the 15-lipoxygenase activity are involved in the induction of LDL oxidation within the arterial wall, provided that sufficient concentrations of lipoproteins are present in the artery. 相似文献
5.
Heparin inhibits the induction of three matrix metalloproteinases (stromelysin, 92-kD gelatinase, and collagenase) in primate arterial smooth muscle cells. 总被引:6,自引:0,他引:6 下载免费PDF全文
R D Kenagy S T Nikkari H G Welgus A W Clowes 《The Journal of clinical investigation》1994,93(5):1987-1993
Heparin inhibits the migration and proliferation of arterial smooth muscle cells and modifies the extracellular matrix. These effects may be the result of heparin's effects on proteinases that degrade the matrix. We have previously reported that heparin inhibits the induction of tissue-type plasminogen activator and interstitial collagenase mRNA. We have investigated the possibility that heparin affects other members of the matrix metalloproteinase family. Phorbol ester increased the levels of mRNA of collagenase, 92-kD gelatinase and stromelysin as well as the synthesis of these proteins. These effects were inhibited by heparin, but not by other glycosaminoglycans, in a dose-dependent manner. The induction of these matrix metalloproteinases was also inhibited by staurosporine and pretreatment with phorbol ester indicating the involvement of the protein kinase C pathway. In contrast, the 72-kD gelatinase was expressed constitutively and was not affected by phorbol ester or heparin. Tissue inhibitor of metalloproteinase-1 was expressed constitutively and was slightly increased by phorbol ester. It was not affected by heparin. Thus, heparin inhibits the production of four proteinases (tissue plasminogen activator, collagenase, stromelysin and 92-kD gelatinase) that form an interdependent system capable of degrading all the major components of the extracellular matrix. 相似文献
6.
7.
Annexin V for flow cytometric detection of phosphatidylserine expression on B cells undergoing apoptosis 总被引:85,自引:19,他引:85
Koopman G; Reutelingsperger CP; Kuijten GA; Keehnen RM; Pals ST; van Oers MH 《Blood》1994,84(5):1415-1420
Apoptosis, or programmed cell death, is a general mechanism for removal of unwanted cells from the immune system. It is characterized by chromatin condensation, a reduction in cell volume, and endonuclease cleavage of DNA into oligonucleosomal length fragments. Apoptosis is also accompanied by a loss of membrane phospholipid asymmetry, resulting in the exposure of phosphatidylserine at the surface of the cell. Expression of phosphatidylserine at the cell surface plays an important role in the recognition and removal of apoptotic cells by macrophages. Here we describe a new method for the detection of apoptotic cells by flow cytometry, using the binding of fluorescein isothiocyanate-labeled annexin V to phosphatidylserine. When Burkitt lymphoma cell lines and freshly isolated germinal center B cells are cultured under apoptosis inducing conditions, all cells showing chromatin condensation strongly stain with annexin V, whereas normal cells are annexin V negative. Moreover, DNA fragmentation is only found in the annexin V-positive cells. The nonvital dye ethidium bromide was found to stain a subpopulation of the annexin V-positive apoptotic cells, increasing with time. Our results indicate that the phase in apoptosis that is characterized by chromatin condensation coincides with phosphatidylserine exposure. Importantly, it precedes membrane damage that might lead to release from the cells of enzymes that are harmful to the surrounding tissues. Annexin V may prove important in further unravelling the regulation of apoptosis. 相似文献
8.
Ritu R. Gill MD MPH Yifan Zheng MD Julianne S. Barlow BA Jagadeesan Jayender PhD Erin E. Girard PhD Philip M. Hartigan MD Lucian R. Chirieac MD Carol J. Belle‐King ST Kristen Murray BSN RN Christopher Sears BSN RN Jon O. Wee MD Michael T. Jaklitsch MD Yolonda L. Colson MD PhD Raphael Bueno MD 《Journal of surgical oncology》2015,112(1):18-25
Purpose
To facilitate localization and resection of small lung nodules, we developed a prospective clinical trial ( ClinicalTrials.gov number NCT01847209) for a novel surgical approach which combines placement of fiducials using intra‐operative C‐arm computed tomography (CT) guidance with standard thoracoscopic resection technique using image‐guided video‐assisted thoracoscopic surgery (iVATS).Methods
Pretrial training was performed in a porcine model using C‐arm CT and needle guidance software. Methodology and workflow for iVATS was developed, and a multi‐modality team was trained. A prospective phase I‐II clinical trial was initiated with the goal of recruiting eligible patients with small peripheral pulmonary nodules. Intra‐operative C‐arm CT scan was utilized for guidance of percutaneous marking with two T‐bars (Kimberly‐Clark, Roswell, GA) followed by VATS resection of the tumor.Results
Twenty‐five patients were enrolled; 23 underwent iVATS, one withdrew, and one lesion resolved. Size of lesions were: 0.6–1.8 cm, mean = 1.3 ± 0.38 cm.. All 23 patients underwent complete resection of their lesions. CT imaging of the resected specimens confirmed the removal of the T‐bars and the nodule. Average and total procedure radiation dose was in the acceptable low range (median = 1501 μGy*m2, range 665–16,326). There were no deaths, and all patients were discharged from the hospital (median length of stay = 4 days, range 2–12). Three patients had postoperative complications: one prolonged air‐leak, one pneumonia, and one ileus.Conclusions
A successful and safe step‐wise process has been established for iVATS, combining intra‐operative C‐arm CT scanning and thoracoscopic surgery in a hybrid operating room. J. Surg. Oncol. 2015 111:18–25. © 2015 The Authors. Journal of Surgical Oncology Published by Wiley Periodicals, Inc. 相似文献9.
白介素与溃疡性结肠炎 总被引:17,自引:1,他引:17
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关. 相似文献
10.
Jacqueline AM Smith DL Patil OT Daniels Y-S Ding J-D Gallezot S Henry KHS Kim S Kshirsagar WJ Martin GP Obedencio E Stangeland PR Tsuruda W Williams RE Carson ST Patil 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)