This is a short report of a recently uncovered resonant phenomenon. The modified Faddeev equation that correctly includes all six open channels is used. The calculation is carried out in s-partial wave. We report a nu...This is a short report of a recently uncovered resonant phenomenon. The modified Faddeev equation that correctly includes all six open channels is used. The calculation is carried out in s-partial wave. We report a number of resonant peaks in the elastic cross sections as well as the wave amplitudes involved. This is the energy region where the Stark-effect induced electric dipole energy split in the target dominates the physics and the Long-Range behavior of the 3-body scattering system. It is found that when the center of mass collision energy in the new channels is in integer proportion to the corresponding electric dipole energy split, Bremsstrahlung photon mediated resonant scattering occurs. The corresponding wave amplitudes deform into wave-packets hundreds to thousands of Bohr radii in width. The physical implication of this phenomenon will be discussed.展开更多
The origin of rings is one of the final arguments in a series explaining solar system formation. Liquid moons placed in circular orbits close to the planet (inside the Roche limit) will deposit ring material as they m...The origin of rings is one of the final arguments in a series explaining solar system formation. Liquid moons placed in circular orbits close to the planet (inside the Roche limit) will deposit ring material as they migrate. Once outside the limit, moons retain this material. Finally, the shape of the moon, Pan, is explained, using the same mechanism that forms rings.展开更多
Background:While traditional meditation practices are known for their mental health benefits,they often face limitations such as restricted access and environmental distractions.To address these challenges and enhance...Background:While traditional meditation practices are known for their mental health benefits,they often face limitations such as restricted access and environmental distractions.To address these challenges and enhance meditation effectiveness,this study implemented an immersive virtual reality meditation(IVRM)program and examined its potentialmental health benefits among university students-a population that frequently experiences significant psychological distress.Methods:Nineteen university students participated in eight 15-min sessions of an IVRM program designed to promote mindfulness and relaxation over the course of one month.Perceived stress and anxiety levels were assessed using validated self-report measures at baseline(T1)and post-intervention(T2).Twotailed paired t-tests were conducted to evaluate the preliminary efficacy of the program,and effect sizes were reported using Cohen’s d.Results:Significant reductions were observed from pre-to post-intervention in perceived stress(t(18)=3.694,p<0.001,SE=0.17,d=−0.85)and perceived anxiety(t(18)=5.113,p<0.01,SE=0.10,d=−1.20),both indicating large effect sizes.Conclusion:Our findings provide preliminary evidence that the IVRMprogramcan reduce stress and anxiety levels in university students.The positive results suggest that IVRM has the potential to serve as a novel,technology-based meditation intervention for individuals at elevated risk for developingmental health disorders.Furthermore,our study suggests important implications for future research.展开更多
This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-...This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-“aging gastropathy”-has prominent structural and functional abnormalities vs young gastric mucosa. Some of these abnormalities include a partial atrophy of gastric glands, impaired mucosal defense (reduced bicarbonate and prostaglandin generation, decreased sensory innervation), increased susceptibility to injury by a variety of damaging agents such as ethanol, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), impaired healing of injury and reduced therapeutic efficacy of ulcer-healing drugs. Detailed analysis of the above changes indicates that the following events occur in aging gastric mucosa: reduced mucosal blood flow and impaired oxygen delivery cause hypoxia, which leads to activation of the early growth response-1 (egr-1) transcription factor. Activation of egr-1, in turn, upregulates the dual specificity phosphatase, phosphatase and tensin homologue deleted on chromosome ten (PTEN) resulting in activation of pro-apoptotic caspase-3 and caspase-9 and reduced expression of the anti-apoptosis protein, survivin. The imbalance between pro- and anti-apoptosis mediators results in increased apoptosis and increased susceptibility to injury. This paradigm has human relevance since increased expression of PTEN and reduced expression of survivin were demonstrated in gastric mucosa of aging individuals. Other potential mechanisms operating in aging gastric mucosa include reduced telomerase activity, increase in replicative cellular senescence, and reduced expression of vascular endothelial growth factor and importin-α-a nuclear transport protein essential for transport of transcription factors to nucleus. Aging gastropathy is an important and clinically relevant issue because of: (1) an aging world population due to prolonged life span; (2) older patients have much greater risk of gastroduodenal ulcers and gastrointestinal complications (e.g., NSAIDs-induced gastric injury) than younger patients; and (3) increased susceptibility of aging gastric mucosa to injury can be potentially reduced or reversed pharmacologically.展开更多
In this editorial we comment on the article by Fukushi K et al published in the recent issue of the World Journal of Gastroenterology 2018; 24(34): 3908-3918. We focus specifically on the mechanisms of the anti-thromb...In this editorial we comment on the article by Fukushi K et al published in the recent issue of the World Journal of Gastroenterology 2018; 24(34): 3908-3918. We focus specifically on the mechanisms of the anti-thrombotic action of aspirin, gastric mucosal injury and aging-related increased susceptibility of gastric mucosa to injury. Aspirin is widely used not only for the management of acute and chronic pain and arthritis, but also importantly for the primary and secondary prevention of cardiovascular events such as myocardial infarcts and strokes. Clinical trials have consistently shown that antiplatelet therapy with long term, low dose aspirin(LDA)-75 to 325 mg daily, dramatically reduces the risk of non-fatal myocardial infarcts, stroke and mortality in patients with established arterial diseases. However, such treatment considerably increases the risk of gastrointestinal(GI) ulcerations and serious bleeding by > 2-4 fold, especially in aging individuals. This risk is further increased in patients using LDA together with other antiplatelet agents, other nonsteroidal anti-inflammatory agents(NSAIDs) and/or alcohol, or in patients with Helicobacter pylori(H. pylori) infection. Previous studies by our group and others have demonstrated prominent structural and functional abnormalities in gastric mucosa of aging individuals(which we refer to as aging gastric mucosa or "aging gastropathy") compared to the gastric mucosa of younger individuals. Aging gastric mucosa has impaired mucosal defense, increased susceptibility to injury by a variety of noxious agents such as aspirin, other NSAIDs and ethanol, and delayed and impaired healing of injury. The mechanism underlying these abnormalities of aging gastric mucosa include reduced mucosal blood flowcausing hypoxia, upregulation of PTEN, activation of proapoptotic caspase-3 and caspase-9, and reduced survivin(anti-apoptosis protein), importin-α(nuclear transport protein), vascular endothelial growth factor, and nerve growth factor. The decision regarding initiation of a long-term LDA therapy should be made after a careful consideration of both cardiovascular and GI risk factors. The latter include a previous history of GI bleeding and/or ulcers, age ≥ 70, male gender, concurrent use of other NSAIDs, alcohol consumption and H. pylori infection. Furthermore, the incidence of GI ulcers and bleeding can be reduced in patients on long term LDA treatment by several measures. Clinicians treating such patients should test for and eradicate H. pylori, instruct patients to avoid alcohol and non-aspirin NSAIDs, including cyclooxygenase-2-selective NSAIDs, and prescribe proton pump inhibitors in patients on LDA therapy. In the future, clinicians may be able to prescribe one of several potential new drugs, which include aspirin associated with phosphatidylcholine(PL2200), which retains all property of aspirin but reduces by approximately 50% LDA-induced GI ulcerations.展开更多
AIM: To study whether indomethacin (IND), a nonselective cyclooxygenase (COX) inhibitor or NS-398 (NS), a COX-2-selective inhibitor, induces apoptosis in human colon cancer cells and which apoptosis-related genes and ...AIM: To study whether indomethacin (IND), a nonselective cyclooxygenase (COX) inhibitor or NS-398 (NS), a COX-2-selective inhibitor, induces apoptosis in human colon cancer cells and which apoptosis-related genes and pathways are involved. METHODS: Human colon cancer Caco-2 cells were treated with either: placebo, IND (0.05-0.5 mmol/L) or NS (0.01-0.2 mmol/L) for 1, 5 and 18 h. We then studied: (1) Cell death by the TUNEL method, (2) mRNA expression of 96 apoptosis-related genes using DNA microarray, (3) expression of selected apoptosis related proteins by Western blotting. RESULTS: Both IND and NS induced apoptosis in 30%-50% of Caco-2 cells in a dose dependent manner. IND (0.1 mmol/L for 1 h) significantly up-regulated pro-apoptotic genes in four families: (1) TNF receptor and ligand, (2) Caspase, (3) Bcl-2 and (4) Caspase recruiting domain. NS treatment up-regulated similar pro-apoptotic genes as IND. In addition, IND also down-regulated anti-apoptotic genes of the IAP family. CONCLUSION: (1) Both non-selective and COX-2-selective NSAIDs induce apoptosis in colon cancer cells in a dose dependent manner. (2) Both NSAIDs induce apoptosis by activating two main apoptotic pathways: the death receptor pathway (involving TNF-R) and the mitochondrial pathway. (3) IND induces apoptosis by up-regulating pro-apoptotic genes and down-regulating anti-apoptotic genes, while NS only up-regulates pro-apoptotic genes. (4) Induction of apoptosis in coloncancer cells by NSAIDs may explain in part, their inhibitory action on colon cancer growth.展开更多
为了提高活性炭在高湿地区对气态碘的吸附性能,采用十三氟辛基三乙氧基硅烷为疏水改性剂,椰壳活性炭为载体,对活性炭进行疏水改性。首先利用接触角分析仪、扫描电子显微镜(scanning electron microscope,SEM)、比表面积分析、能谱分析(e...为了提高活性炭在高湿地区对气态碘的吸附性能,采用十三氟辛基三乙氧基硅烷为疏水改性剂,椰壳活性炭为载体,对活性炭进行疏水改性。首先利用接触角分析仪、扫描电子显微镜(scanning electron microscope,SEM)、比表面积分析、能谱分析(energy dispersive spectroscopy,EDS)等手段表征其结构和疏水性能。然后通过气态碘的吸附实验探究改性活性炭在高湿环境下对气态碘的吸附性能,同时考察了温度、速度对其吸附性能的影响规律。表征结果表面,改性处理后的活性炭对水的静态接触角为152°疏水性良好,扫描电子显微镜、能谱分析均证实活性炭表面覆盖了疏水薄膜且疏水改性对活性炭的孔隙结构影响小。实验结果表明,改性后的活性炭具有良好的选择吸附性。环境湿度的增加对活性炭吸附性能影响较小,随湿度增加活性炭对气态碘的吸附量仅下降了20.02%,而改性前的活性炭吸附量下降了78.26%,改性前后最大吸附系数差值为99.94 mg/g。气流温度、速度和压力对吸附性能产生一定影响,过高的温度和速度会使活性炭的吸附能力下降,压力的增加会使活性炭的吸附能力上升。展开更多
AIM: To investigate the use of fully covered metal stents in benign biliary strictures (BBS) and bile leaks. METHODS: We studied 17 patients, at Harbor-UCLA Medical center (Los Angeles), with BBS (n=12) and bile leaks...AIM: To investigate the use of fully covered metal stents in benign biliary strictures (BBS) and bile leaks. METHODS: We studied 17 patients, at Harbor-UCLA Medical center (Los Angeles), with BBS (n=12) and bile leaks (n=5) from July 2007 to February 2012 that had received placement of fully covered self-expanding metal stents (FCSEMs). Fourteen patients had endoscopic placement of VIABIL (Conmed, Utica, New York, United States) stents and three had Wallflex (Boston Scientific, Mass) stents. FCSEMS were 8 mm or 10 mm in diameter and 4 cm to 10 cm in length. Patients were followed at regular intervals to evaluate for symptoms and liver function tests. FCSEMS were removed after 4 or more weeks. Resolution of BBS and leak was documented cholangiographically following stent removal. Stent patency can be defined as adequate bile and contrast flow from the stent and into the ampulla during endoscopic retrograde cholangiopancreatography (ERCP) without clinical signs and/or symptoms of biliary obstruction. Criterion for bile leak resolution at ERCP is defined as absence of contrast extravasation from the common bile duct, cystic duct remanent, or gall blad-der fossa. Rate of complications such as migration, and instent occlusion were recorded. Failure of endoscopic therapy was defined as persistent biliary stenosis or continuous biliary leakage after 12 mo of stent placement. RESULTS: All 17 patients underwent successful FC- SEMS placement and removal. Etiologies of BBS included: cholecystectomies (n=8), cholelithiasis (n=2), hepatic artery compression (n=1), pancreatitis (n=2), and Whipple procedure (n=1). All bile leaks occurred following cholecystectomy. The anatomic location of BBS varied: distal common bile duct (n=7), common hepatic duct (n=1), hepaticojejunal anastomosis (n=2), right intrahepatic duct (n=1), and choledochoduo-denal anastomatic junction (n=1). All bile leaks were found to be at the cystic duct. Twelve of 17 patients had failed prior stent placement or exchange. Resolution of the biliary strictures and bile leaks was achieved in 16 of 17 patients (94%). The overall median stent time was 63 d (range 27-251 d). The median stent time for the BBS group and bile leak group was 62 ± 58 d (range 27-199 d) and 92 ± 81 d (range 48-251 d), respectively. All 17 patients underwent successful FCSEMS removal. Long term follow-up was obtained for a median of 575 d (range 28-1435 d). Complications occurred in 5 of 17 patients (29%) and included: migration (n=2), stent clogging (n=1), cholangitis (n=1), and sepsis with hepatic abscess (n=1). CONCLUSION: Placement of fully covered self-expanding metal stents may be used in the management of benign biliary strictures and bile leaks with a low rate of complications.展开更多
Serum response factor(SRF) is a transcription factor that regulates many genes involved in cellular activities such as proliferation,migration,differentiation,angiogenesis,and apoptosis.Although it has only been known...Serum response factor(SRF) is a transcription factor that regulates many genes involved in cellular activities such as proliferation,migration,differentiation,angiogenesis,and apoptosis.Although it has only been known for about two decades,SRF has been studied extensively.To date,over a thousand SRF studies have been published,but it still remains a hot topic.Due to its critical role in mesoderm-derived tissues,most of the SRF studies focused on muscle structure/function,cardiovascular development/maintenance,and smooth muscle generation/repair.Recently,SRF has received more attention in the digestive field and several important discoveries have been made.This review will summarize what we have learned about SRF in the gastrointestinal tract and provide insights into possible future directions in this area.展开更多
AIM:To assess the risk of biliary and pancreatic cancers in a large cohort of patients with type 2 diabetes mellitus(DM) .METHODS:Eligibility for this study included patients with type 2 DM(ICD-9 code 250.0) who were ...AIM:To assess the risk of biliary and pancreatic cancers in a large cohort of patients with type 2 diabetes mellitus(DM) .METHODS:Eligibility for this study included patients with type 2 DM(ICD-9 code 250.0) who were discharged from Department of Veteran Affairs hospitals between 1990 and 2000.Non-matched control patients without DM were selected from the same patient treatment files during the same period.Demographic information included age,sex and race.Secondary diagnoses included known risk factors based on their ICD-9 codes.By multivariate logistic regression,the occurrence of biliary and pancreatic cancer was compared between case subjects with DM and controls without DM.RESULTS:A total of 1172496 case and control subjects were analyzed.The mean age for study and control subjects was 65.8 ± 11.3 and 64.8 ± 12.6 years,respectively.The frequency of pancreatic cancer in subjects with DM was increased(0.9%) in comparison to control subjects(0.3%) with an OR of 3.22(95% CI:3.03-3.42) .The incidence of gallbladder andextrahepatic biliary cancers was increased by twofold in diabetic patients when compared to controls.The OR and 95% CI were 2.20(1.56-3.00) and 2.10(1.61-2.53) ,respectively.CONCLUSION:Our study demonstrated that patients with DM have a threefold increased risk for developing pancreatic cancer and a twofold risk for developing biliary cancer.展开更多
Ground penetrating radar（GPR） can be used to image fractures and monitor fluid flow in the subsurface. Conventional GPR imaging uses single-polarization, co-polarized acquisition. We examine the use of cross-polariz...Ground penetrating radar（GPR） can be used to image fractures and monitor fluid flow in the subsurface. Conventional GPR imaging uses single-polarization, co-polarized acquisition. We examine the use of cross-polarized GPR signals for imaging flow channeling in a discrete horizontal fracture. Numerical modeling（FDTD） demonstrates that when the fracture channel is oriented at an oblique angle to the survey line, depolarization of the GPR signal results in scattered energy along the cross-polarized components. When the channel is oriented parallel or orthogonal to the survey line, all scattered energy is captured by the co-polarized components and no signal is present in the cross-polarized orientation. Multipolarization, time-lapse 3D GPR field data were acquired at the Altona Flat Rock test site in New York State. The GPR surveys were conducted during background fresh fracture water conditions and during a natural gradient saline tracer test which was used to highlight flow channels along a sub-horizontal fracture. Amplitude analysis of the cross-polarized data reveals flow channeling that is in agreement with the co-polarized GPR images and with independent hydraulic tests. This investigation demonstrates that cross-polarized components of GPR signals can be used to enhance imaging of flow channels in fractured media.展开更多
AIM： To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions （HML） and the mechanism of gastroprotective effect of sucralfate.ME...AIM： To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions （HML） and the mechanism of gastroprotective effect of sucralfate.METHODS： Rats were given 1 mL of 75% ethanol, 25%NaCl, 0.6 mol/L HCI, 0.2 mol/L NaOH or 1% ammonia solutions intragastrically （i.g.） and sacrificed 1, 3, 6 or 12 min later. Total （reduced and oxidized） glutathione （GSH ＋ GSSG）, glutathione disulfide （GSSG）, protein free sulfhydryls （PSH）, protein-glutathione mixed disulfides （PSSG） and protein cystine disulfides （PSSP） were measured in gastric mucosa and liver.RESULTS： Reduced glutathione （GSH） was depleted in the gastric mucosa after ethanol, HCI or NaCl exposure,while oxidized glutathione （GSSG） concentrations increased, except by HCI and NaOH exposure. Decreased levels of PSH after exposure to ethanol were observed,NaCl or NaOH while the total protein disulfides were increased. Ratios of reduced to oxidized glutathione or sulfhydrils to disulfides were decreased by all chemicals.No changes in thiol homeostasis were detected in the liver after i.g. abbreviation should be spelled out the first time here administration of ethanol. Sucralfate increased the concentrations of GSH and PSH and prevented the ethanol-induced changes in gastric mucosal thiol concentrations.CONCLUSION： Our modified methods are now suitable for direct measurements of major protein and nonprotein thiols/disulfides in the gastric mucosa or liver.A common element in the pathogenesis of chemically induced HML and in the mechanism of gastroprotective drugs seems to be the decreased ratios of reduced and oxidized glutathione as well as protein sulfhydryls and disulfides.展开更多
AIM: To determine the effect of ethnicity on the severity of reflux esophagitis (RE) and its complications. METHODS: A retrospective search of the endoscopy database at the University of Florida Health Science Center/...AIM: To determine the effect of ethnicity on the severity of reflux esophagitis (RE) and its complications. METHODS: A retrospective search of the endoscopy database at the University of Florida Health Science Center/Jacksonville for all cases of reflux esophagitis and its complications from January 1 to March 31, 2001 was performed. Inclusion criteria were endoscopic evidence of esophagitis using the LA classif ication, reflux related complications and self-reported ethnicity. The data obtained included esophagitis grade, presence of a hiatal hernia, esophageal ulcer, stricture and Barrett's esophagus, and endoscopy indication. RESULTS: The search identified 259 patients with RE or its complications, of which 171 were non-Hispanic whites and 88 were African Americans. The mean ages and male/female ratios were similar in the two groups. RE grade, esophageal ulcer, stricture and hiatal hernia frequency were likewise similar in the groups. Barrett's esophagus was present more often in non-Hispanic whites than in African Americans (15.8% vs 4.5%; P < 0.01). Heartburn was a more frequent indication for endoscopy in non-Hispanic whites with erosive esophagitis than in African Americans (28.1% vs 7.9%; P < 0.001). CONCLUSION: Distribution of RE grade and frequency of reflux-related esophageal ulcer, stricture andhiatal hernia are similar in non-Hispanic whites and African Americans. Heartburn was more frequently and nausea/vomiting less frequently reported as the primary endoscopic indication in non-Hispanic whites compared with African Americans with erosive esophagitis or its complications. African Americans have a decreased prevalence of Barrett's esophagus compared with non-Hispanic whites.展开更多
AIM To perform meta-analysis of the use of Endocuff during average risk screening colonoscopy.METHODS Scopus, Cochrane databases, MEDLINE/Pub Med, and CINAHL were searched in April 2016. Abstracts from Digestive Disea...AIM To perform meta-analysis of the use of Endocuff during average risk screening colonoscopy.METHODS Scopus, Cochrane databases, MEDLINE/Pub Med, and CINAHL were searched in April 2016. Abstracts from Digestive Disease Week, United European Gastroenterology, and the American College of Gastroenterology meeting were also searched from 2004-2015. Studies comparing EC-assisted colonoscopy(EAC) to standard colonoscopy, for any indication, were included in the analysis. The analysis was conducted by using the Mantel-Haenszel or DerS imonian and Laird models with the odds ratio(OR) to assess adenoma detection, cecal intubation rate, and complications performed. RESULTS Nine studies(n = 5624 patients) were included in the analysis. Compared to standard colonoscopy, procedures performed with EC had higher frequencies for adenoma(OR = 1.49, 95%CI: 1.23-1.80; P = 0.03), and sessile serrated adenomas detection(OR = 2.34 95%CI: 1.63-3.36; P < 0.001). There was no significant difference in cecal intubation rates between the EACgroup and standard colonoscopy(OR = 1.26, 95%CI: 0.70-2.27, I2 = 0%; P = 0.44). EAC was associated with a higher risk of complications, most commonly being superficial mucosal injury without higher frequency for perforation.CONCLUSION The use of an EC on colonoscopy appears to improve pre-cancerous polyp detection without any difference in cecal intubation rates compared to standard colonoscopy.展开更多
Remote sensing technology has been widely recognized for contributing to emergency response efforts after the World Trade Center attack on September 11th, 2001. The need to coordinate activities in the midst of a dens...Remote sensing technology has been widely recognized for contributing to emergency response efforts after the World Trade Center attack on September 11th, 2001. The need to coordinate activities in the midst of a dense, yet relatively small area, made the combination of imagery and mapped data strategically useful. This paper reviews the role played by aerial photography, satellite imagery, and LIDAR data at Ground Zero. It examines how emergency managers utilized these datasets, and identifies significant problems that were encountered. It goes on to explore additional ways in which imagery could have been used, while presenting recommendations for more effective use in future disasters and Homeland Security applications. To plan adequately for future events, it was important to capture knowledge from individuals who responded to the World Trade Center attack. In recognition, interviews with key emergency management and geographic information system (GIS) personnel provide the basis of this paper. Successful techniques should not be forgotten, or serious problems dismissed. Although widely used after September 11th, it is important to recognize that with better planning, remote sensing and GIS could have played an even greater role. Together with a data acquisition timeline, an expanded discussion of these issues is available in the MCEER/NSF report “Emergency Response in the Wake of the World Trade Center Attack; The Remote Sensing Perspective” (Huyck and Adams, 2002) Keywords World Trade Center (WTC) - terrorism - emergency response - emergency management - ground zero - remote sensing - emergency operations - disasters - geographic information systems (GIS) - satellite imagery - synthetic aperture radar (SAR) - light detection and ranging imagery (LIDAR)展开更多
文摘This is a short report of a recently uncovered resonant phenomenon. The modified Faddeev equation that correctly includes all six open channels is used. The calculation is carried out in s-partial wave. We report a number of resonant peaks in the elastic cross sections as well as the wave amplitudes involved. This is the energy region where the Stark-effect induced electric dipole energy split in the target dominates the physics and the Long-Range behavior of the 3-body scattering system. It is found that when the center of mass collision energy in the new channels is in integer proportion to the corresponding electric dipole energy split, Bremsstrahlung photon mediated resonant scattering occurs. The corresponding wave amplitudes deform into wave-packets hundreds to thousands of Bohr radii in width. The physical implication of this phenomenon will be discussed.
文摘The origin of rings is one of the final arguments in a series explaining solar system formation. Liquid moons placed in circular orbits close to the planet (inside the Roche limit) will deposit ring material as they migrate. Once outside the limit, moons retain this material. Finally, the shape of the moon, Pan, is explained, using the same mechanism that forms rings.
文摘Background:While traditional meditation practices are known for their mental health benefits,they often face limitations such as restricted access and environmental distractions.To address these challenges and enhance meditation effectiveness,this study implemented an immersive virtual reality meditation(IVRM)program and examined its potentialmental health benefits among university students-a population that frequently experiences significant psychological distress.Methods:Nineteen university students participated in eight 15-min sessions of an IVRM program designed to promote mindfulness and relaxation over the course of one month.Perceived stress and anxiety levels were assessed using validated self-report measures at baseline(T1)and post-intervention(T2).Twotailed paired t-tests were conducted to evaluate the preliminary efficacy of the program,and effect sizes were reported using Cohen’s d.Results:Significant reductions were observed from pre-to post-intervention in perceived stress(t(18)=3.694,p<0.001,SE=0.17,d=−0.85)and perceived anxiety(t(18)=5.113,p<0.01,SE=0.10,d=−1.20),both indicating large effect sizes.Conclusion:Our findings provide preliminary evidence that the IVRMprogramcan reduce stress and anxiety levels in university students.The positive results suggest that IVRM has the potential to serve as a novel,technology-based meditation intervention for individuals at elevated risk for developingmental health disorders.Furthermore,our study suggests important implications for future research.
基金教育部人文社会科学重点研究基地重大项目“沿黄黄金旅游带构建及其可持续发展研究”(12JJD790005)阶段性成果国家社会科学基金青年项目“大型节事举办后中国旅游形象演变机理及和谐发展战略研究”(12CGL057)阶段性成果+1 种基金国家社会科学基金项目“我国城镇公共休闲服务供给方式及基本公共休闲服务均等化研究”(13BGL095)阶段性成果国家留学基金项目“Visiting the California State University,Long Beach”([2015]5104)阶段性成果
基金Supported by VA Merit Review grant to Tarnawski AS
文摘This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-“aging gastropathy”-has prominent structural and functional abnormalities vs young gastric mucosa. Some of these abnormalities include a partial atrophy of gastric glands, impaired mucosal defense (reduced bicarbonate and prostaglandin generation, decreased sensory innervation), increased susceptibility to injury by a variety of damaging agents such as ethanol, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), impaired healing of injury and reduced therapeutic efficacy of ulcer-healing drugs. Detailed analysis of the above changes indicates that the following events occur in aging gastric mucosa: reduced mucosal blood flow and impaired oxygen delivery cause hypoxia, which leads to activation of the early growth response-1 (egr-1) transcription factor. Activation of egr-1, in turn, upregulates the dual specificity phosphatase, phosphatase and tensin homologue deleted on chromosome ten (PTEN) resulting in activation of pro-apoptotic caspase-3 and caspase-9 and reduced expression of the anti-apoptosis protein, survivin. The imbalance between pro- and anti-apoptosis mediators results in increased apoptosis and increased susceptibility to injury. This paradigm has human relevance since increased expression of PTEN and reduced expression of survivin were demonstrated in gastric mucosa of aging individuals. Other potential mechanisms operating in aging gastric mucosa include reduced telomerase activity, increase in replicative cellular senescence, and reduced expression of vascular endothelial growth factor and importin-α-a nuclear transport protein essential for transport of transcription factors to nucleus. Aging gastropathy is an important and clinically relevant issue because of: (1) an aging world population due to prolonged life span; (2) older patients have much greater risk of gastroduodenal ulcers and gastrointestinal complications (e.g., NSAIDs-induced gastric injury) than younger patients; and (3) increased susceptibility of aging gastric mucosa to injury can be potentially reduced or reversed pharmacologically.
基金Merit Review Award from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service,No.I01 BX000626-05A2 to Tarnawski AS
文摘In this editorial we comment on the article by Fukushi K et al published in the recent issue of the World Journal of Gastroenterology 2018; 24(34): 3908-3918. We focus specifically on the mechanisms of the anti-thrombotic action of aspirin, gastric mucosal injury and aging-related increased susceptibility of gastric mucosa to injury. Aspirin is widely used not only for the management of acute and chronic pain and arthritis, but also importantly for the primary and secondary prevention of cardiovascular events such as myocardial infarcts and strokes. Clinical trials have consistently shown that antiplatelet therapy with long term, low dose aspirin(LDA)-75 to 325 mg daily, dramatically reduces the risk of non-fatal myocardial infarcts, stroke and mortality in patients with established arterial diseases. However, such treatment considerably increases the risk of gastrointestinal(GI) ulcerations and serious bleeding by > 2-4 fold, especially in aging individuals. This risk is further increased in patients using LDA together with other antiplatelet agents, other nonsteroidal anti-inflammatory agents(NSAIDs) and/or alcohol, or in patients with Helicobacter pylori(H. pylori) infection. Previous studies by our group and others have demonstrated prominent structural and functional abnormalities in gastric mucosa of aging individuals(which we refer to as aging gastric mucosa or "aging gastropathy") compared to the gastric mucosa of younger individuals. Aging gastric mucosa has impaired mucosal defense, increased susceptibility to injury by a variety of noxious agents such as aspirin, other NSAIDs and ethanol, and delayed and impaired healing of injury. The mechanism underlying these abnormalities of aging gastric mucosa include reduced mucosal blood flowcausing hypoxia, upregulation of PTEN, activation of proapoptotic caspase-3 and caspase-9, and reduced survivin(anti-apoptosis protein), importin-α(nuclear transport protein), vascular endothelial growth factor, and nerve growth factor. The decision regarding initiation of a long-term LDA therapy should be made after a careful consideration of both cardiovascular and GI risk factors. The latter include a previous history of GI bleeding and/or ulcers, age ≥ 70, male gender, concurrent use of other NSAIDs, alcohol consumption and H. pylori infection. Furthermore, the incidence of GI ulcers and bleeding can be reduced in patients on long term LDA treatment by several measures. Clinicians treating such patients should test for and eradicate H. pylori, instruct patients to avoid alcohol and non-aspirin NSAIDs, including cyclooxygenase-2-selective NSAIDs, and prescribe proton pump inhibitors in patients on LDA therapy. In the future, clinicians may be able to prescribe one of several potential new drugs, which include aspirin associated with phosphatidylcholine(PL2200), which retains all property of aspirin but reduces by approximately 50% LDA-induced GI ulcerations.
基金Supported by VA Merit Review to Andrzej S Tarnawski
文摘AIM: To study whether indomethacin (IND), a nonselective cyclooxygenase (COX) inhibitor or NS-398 (NS), a COX-2-selective inhibitor, induces apoptosis in human colon cancer cells and which apoptosis-related genes and pathways are involved. METHODS: Human colon cancer Caco-2 cells were treated with either: placebo, IND (0.05-0.5 mmol/L) or NS (0.01-0.2 mmol/L) for 1, 5 and 18 h. We then studied: (1) Cell death by the TUNEL method, (2) mRNA expression of 96 apoptosis-related genes using DNA microarray, (3) expression of selected apoptosis related proteins by Western blotting. RESULTS: Both IND and NS induced apoptosis in 30%-50% of Caco-2 cells in a dose dependent manner. IND (0.1 mmol/L for 1 h) significantly up-regulated pro-apoptotic genes in four families: (1) TNF receptor and ligand, (2) Caspase, (3) Bcl-2 and (4) Caspase recruiting domain. NS treatment up-regulated similar pro-apoptotic genes as IND. In addition, IND also down-regulated anti-apoptotic genes of the IAP family. CONCLUSION: (1) Both non-selective and COX-2-selective NSAIDs induce apoptosis in colon cancer cells in a dose dependent manner. (2) Both NSAIDs induce apoptosis by activating two main apoptotic pathways: the death receptor pathway (involving TNF-R) and the mitochondrial pathway. (3) IND induces apoptosis by up-regulating pro-apoptotic genes and down-regulating anti-apoptotic genes, while NS only up-regulates pro-apoptotic genes. (4) Induction of apoptosis in coloncancer cells by NSAIDs may explain in part, their inhibitory action on colon cancer growth.
文摘AIM: To investigate the use of fully covered metal stents in benign biliary strictures (BBS) and bile leaks. METHODS: We studied 17 patients, at Harbor-UCLA Medical center (Los Angeles), with BBS (n=12) and bile leaks (n=5) from July 2007 to February 2012 that had received placement of fully covered self-expanding metal stents (FCSEMs). Fourteen patients had endoscopic placement of VIABIL (Conmed, Utica, New York, United States) stents and three had Wallflex (Boston Scientific, Mass) stents. FCSEMS were 8 mm or 10 mm in diameter and 4 cm to 10 cm in length. Patients were followed at regular intervals to evaluate for symptoms and liver function tests. FCSEMS were removed after 4 or more weeks. Resolution of BBS and leak was documented cholangiographically following stent removal. Stent patency can be defined as adequate bile and contrast flow from the stent and into the ampulla during endoscopic retrograde cholangiopancreatography (ERCP) without clinical signs and/or symptoms of biliary obstruction. Criterion for bile leak resolution at ERCP is defined as absence of contrast extravasation from the common bile duct, cystic duct remanent, or gall blad-der fossa. Rate of complications such as migration, and instent occlusion were recorded. Failure of endoscopic therapy was defined as persistent biliary stenosis or continuous biliary leakage after 12 mo of stent placement. RESULTS: All 17 patients underwent successful FC- SEMS placement and removal. Etiologies of BBS included: cholecystectomies (n=8), cholelithiasis (n=2), hepatic artery compression (n=1), pancreatitis (n=2), and Whipple procedure (n=1). All bile leaks occurred following cholecystectomy. The anatomic location of BBS varied: distal common bile duct (n=7), common hepatic duct (n=1), hepaticojejunal anastomosis (n=2), right intrahepatic duct (n=1), and choledochoduo-denal anastomatic junction (n=1). All bile leaks were found to be at the cystic duct. Twelve of 17 patients had failed prior stent placement or exchange. Resolution of the biliary strictures and bile leaks was achieved in 16 of 17 patients (94%). The overall median stent time was 63 d (range 27-251 d). The median stent time for the BBS group and bile leak group was 62 ± 58 d (range 27-199 d) and 92 ± 81 d (range 48-251 d), respectively. All 17 patients underwent successful FCSEMS removal. Long term follow-up was obtained for a median of 575 d (range 28-1435 d). Complications occurred in 5 of 17 patients (29%) and included: migration (n=2), stent clogging (n=1), cholangitis (n=1), and sepsis with hepatic abscess (n=1). CONCLUSION: Placement of fully covered self-expanding metal stents may be used in the management of benign biliary strictures and bile leaks with a low rate of complications.
基金Supported by The Department of Veterans Affairs of the United States and the American Heart Association grants to Dr Chai J
文摘Serum response factor(SRF) is a transcription factor that regulates many genes involved in cellular activities such as proliferation,migration,differentiation,angiogenesis,and apoptosis.Although it has only been known for about two decades,SRF has been studied extensively.To date,over a thousand SRF studies have been published,but it still remains a hot topic.Due to its critical role in mesoderm-derived tissues,most of the SRF studies focused on muscle structure/function,cardiovascular development/maintenance,and smooth muscle generation/repair.Recently,SRF has received more attention in the digestive field and several important discoveries have been made.This review will summarize what we have learned about SRF in the gastrointestinal tract and provide insights into possible future directions in this area.
文摘AIM:To assess the risk of biliary and pancreatic cancers in a large cohort of patients with type 2 diabetes mellitus(DM) .METHODS:Eligibility for this study included patients with type 2 DM(ICD-9 code 250.0) who were discharged from Department of Veteran Affairs hospitals between 1990 and 2000.Non-matched control patients without DM were selected from the same patient treatment files during the same period.Demographic information included age,sex and race.Secondary diagnoses included known risk factors based on their ICD-9 codes.By multivariate logistic regression,the occurrence of biliary and pancreatic cancer was compared between case subjects with DM and controls without DM.RESULTS:A total of 1172496 case and control subjects were analyzed.The mean age for study and control subjects was 65.8 ± 11.3 and 64.8 ± 12.6 years,respectively.The frequency of pancreatic cancer in subjects with DM was increased(0.9%) in comparison to control subjects(0.3%) with an OR of 3.22(95% CI:3.03-3.42) .The incidence of gallbladder andextrahepatic biliary cancers was increased by twofold in diabetic patients when compared to controls.The OR and 95% CI were 2.20(1.56-3.00) and 2.10(1.61-2.53) ,respectively.CONCLUSION:Our study demonstrated that patients with DM have a threefold increased risk for developing pancreatic cancer and a twofold risk for developing biliary cancer.
基金supported by the US Department of Energy Environmental Remediation Sciences Program (No. 07-358509)the US Department of Energy Geothermal Technologies Program (No. DE-EE0002767)GPR instrumentation was funded by the National Science Foundation (No. EAR/IF-0345445)
文摘Ground penetrating radar（GPR） can be used to image fractures and monitor fluid flow in the subsurface. Conventional GPR imaging uses single-polarization, co-polarized acquisition. We examine the use of cross-polarized GPR signals for imaging flow channeling in a discrete horizontal fracture. Numerical modeling（FDTD） demonstrates that when the fracture channel is oriented at an oblique angle to the survey line, depolarization of the GPR signal results in scattered energy along the cross-polarized components. When the channel is oriented parallel or orthogonal to the survey line, all scattered energy is captured by the co-polarized components and no signal is present in the cross-polarized orientation. Multipolarization, time-lapse 3D GPR field data were acquired at the Altona Flat Rock test site in New York State. The GPR surveys were conducted during background fresh fracture water conditions and during a natural gradient saline tracer test which was used to highlight flow channels along a sub-horizontal fracture. Amplitude analysis of the cross-polarized data reveals flow channeling that is in agreement with the co-polarized GPR images and with independent hydraulic tests. This investigation demonstrates that cross-polarized components of GPR signals can be used to enhance imaging of flow channels in fractured media.
文摘AIM： To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions （HML） and the mechanism of gastroprotective effect of sucralfate.METHODS： Rats were given 1 mL of 75% ethanol, 25%NaCl, 0.6 mol/L HCI, 0.2 mol/L NaOH or 1% ammonia solutions intragastrically （i.g.） and sacrificed 1, 3, 6 or 12 min later. Total （reduced and oxidized） glutathione （GSH ＋ GSSG）, glutathione disulfide （GSSG）, protein free sulfhydryls （PSH）, protein-glutathione mixed disulfides （PSSG） and protein cystine disulfides （PSSP） were measured in gastric mucosa and liver.RESULTS： Reduced glutathione （GSH） was depleted in the gastric mucosa after ethanol, HCI or NaCl exposure,while oxidized glutathione （GSSG） concentrations increased, except by HCI and NaOH exposure. Decreased levels of PSH after exposure to ethanol were observed,NaCl or NaOH while the total protein disulfides were increased. Ratios of reduced to oxidized glutathione or sulfhydrils to disulfides were decreased by all chemicals.No changes in thiol homeostasis were detected in the liver after i.g. abbreviation should be spelled out the first time here administration of ethanol. Sucralfate increased the concentrations of GSH and PSH and prevented the ethanol-induced changes in gastric mucosal thiol concentrations.CONCLUSION： Our modified methods are now suitable for direct measurements of major protein and nonprotein thiols/disulfides in the gastric mucosa or liver.A common element in the pathogenesis of chemically induced HML and in the mechanism of gastroprotective drugs seems to be the decreased ratios of reduced and oxidized glutathione as well as protein sulfhydryls and disulfides.
文摘AIM: To determine the effect of ethnicity on the severity of reflux esophagitis (RE) and its complications. METHODS: A retrospective search of the endoscopy database at the University of Florida Health Science Center/Jacksonville for all cases of reflux esophagitis and its complications from January 1 to March 31, 2001 was performed. Inclusion criteria were endoscopic evidence of esophagitis using the LA classif ication, reflux related complications and self-reported ethnicity. The data obtained included esophagitis grade, presence of a hiatal hernia, esophageal ulcer, stricture and Barrett's esophagus, and endoscopy indication. RESULTS: The search identified 259 patients with RE or its complications, of which 171 were non-Hispanic whites and 88 were African Americans. The mean ages and male/female ratios were similar in the two groups. RE grade, esophageal ulcer, stricture and hiatal hernia frequency were likewise similar in the groups. Barrett's esophagus was present more often in non-Hispanic whites than in African Americans (15.8% vs 4.5%; P < 0.01). Heartburn was a more frequent indication for endoscopy in non-Hispanic whites with erosive esophagitis than in African Americans (28.1% vs 7.9%; P < 0.001). CONCLUSION: Distribution of RE grade and frequency of reflux-related esophageal ulcer, stricture andhiatal hernia are similar in non-Hispanic whites and African Americans. Heartburn was more frequently and nausea/vomiting less frequently reported as the primary endoscopic indication in non-Hispanic whites compared with African Americans with erosive esophagitis or its complications. African Americans have a decreased prevalence of Barrett's esophagus compared with non-Hispanic whites.
文摘AIM To perform meta-analysis of the use of Endocuff during average risk screening colonoscopy.METHODS Scopus, Cochrane databases, MEDLINE/Pub Med, and CINAHL were searched in April 2016. Abstracts from Digestive Disease Week, United European Gastroenterology, and the American College of Gastroenterology meeting were also searched from 2004-2015. Studies comparing EC-assisted colonoscopy(EAC) to standard colonoscopy, for any indication, were included in the analysis. The analysis was conducted by using the Mantel-Haenszel or DerS imonian and Laird models with the odds ratio(OR) to assess adenoma detection, cecal intubation rate, and complications performed. RESULTS Nine studies(n = 5624 patients) were included in the analysis. Compared to standard colonoscopy, procedures performed with EC had higher frequencies for adenoma(OR = 1.49, 95%CI: 1.23-1.80; P = 0.03), and sessile serrated adenomas detection(OR = 2.34 95%CI: 1.63-3.36; P < 0.001). There was no significant difference in cecal intubation rates between the EACgroup and standard colonoscopy(OR = 1.26, 95%CI: 0.70-2.27, I2 = 0%; P = 0.44). EAC was associated with a higher risk of complications, most commonly being superficial mucosal injury without higher frequency for perforation.CONCLUSION The use of an EC on colonoscopy appears to improve pre-cancerous polyp detection without any difference in cecal intubation rates compared to standard colonoscopy.
基金the Earthquake Engineering Research Centers Program of the National Science Foundation(NSF) under a Supplement to Award Number ECC-9701471 to the Multidisciplinary Center for Earthquake Engineering Research
文摘Remote sensing technology has been widely recognized for contributing to emergency response efforts after the World Trade Center attack on September 11th, 2001. The need to coordinate activities in the midst of a dense, yet relatively small area, made the combination of imagery and mapped data strategically useful. This paper reviews the role played by aerial photography, satellite imagery, and LIDAR data at Ground Zero. It examines how emergency managers utilized these datasets, and identifies significant problems that were encountered. It goes on to explore additional ways in which imagery could have been used, while presenting recommendations for more effective use in future disasters and Homeland Security applications. To plan adequately for future events, it was important to capture knowledge from individuals who responded to the World Trade Center attack. In recognition, interviews with key emergency management and geographic information system (GIS) personnel provide the basis of this paper. Successful techniques should not be forgotten, or serious problems dismissed. Although widely used after September 11th, it is important to recognize that with better planning, remote sensing and GIS could have played an even greater role. Together with a data acquisition timeline, an expanded discussion of these issues is available in the MCEER/NSF report “Emergency Response in the Wake of the World Trade Center Attack; The Remote Sensing Perspective” (Huyck and Adams, 2002) Keywords World Trade Center (WTC) - terrorism - emergency response - emergency management - ground zero - remote sensing - emergency operations - disasters - geographic information systems (GIS) - satellite imagery - synthetic aperture radar (SAR) - light detection and ranging imagery (LIDAR)
