We consider a system of neutral equations with unbounded delay, and derive conditions on Liapunov functionals to ensure that the solutions are uniformly bounded and uniformly ultimately bounded.
This article discusses the general boundary value problem for the nonlinear uniformly elliptic equation of second order in D (0.1) and the boundary condition,(0.2) in a multiply connected infinite domain D with the bo...This article discusses the general boundary value problem for the nonlinear uniformly elliptic equation of second order in D (0.1) and the boundary condition,(0.2) in a multiply connected infinite domain D with the boundary T. The above boundary value problem is called Problem G. Problem G extends the work [8] in which the equation (0.1) includes a nonlinear lower term and the boundary condition (0.2) is more general. If the complex equation (0.1) and the boundary condition (0.2) meet certain assumptions, some solvability results for Problem G can be obtained. By using reduction to absurdity, we first discuss a priori estimates of solutions and solvability for a modified problem. Then we present results on solvability of Problem G.展开更多
The nonpreemptive assignment of independent tasks to a system of m uniform processors isexamined with the objective of minimizing the makespan. Using r_m, the ratio of the fasest speed tothe slowest speed of the syste...The nonpreemptive assignment of independent tasks to a system of m uniform processors isexamined with the objective of minimizing the makespan. Using r_m, the ratio of the fasest speed tothe slowest speed of the system, as a parameter, we assess the performance of LPT (largestprocessing time) schedule with respect to optimal schedules. It is shown thet the worst-case boundfor the ratio of the two schedule lengths is between展开更多
There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons...There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).展开更多
The field of diffusion micro structural magnetic resonance(MR)aims to probe timedependent diffusion,i.e.,an ensemble-averaged mean-squared displacement that is not linear in time.This time-dependence contains rich inf...The field of diffusion micro structural magnetic resonance(MR)aims to probe timedependent diffusion,i.e.,an ensemble-averaged mean-squared displacement that is not linear in time.This time-dependence contains rich information about the surrounding microenvironment.MR methods to measure time-dependent diffusion quantitatively,however,require either non-standard pulse sequences,such as oscillating gradients,or make non-physical assumptions,such as infinitely narrow gradient pulses.Here,we argue that standard spin echo and stimulated echo MR sequences can be used to probe directly.In particular,we propose a framework in which the log-signal ratio obtained from a pair of measurements with different inter-pulse spacingΔis proportional to the MSD between these twoΔvalues along the gradient direction x:-.The framework is quantitative for short,finite-duration gradient pulses and under the Gaussian phase approximation(GPA).To validate the framework,we consider onedimensional diffusion between impermeable,parallel planes,as well as periodicallyspaced,permeable planes.Excellent agreement is obtained between the estimation and the ground truth in the regime where the GPA is expected to hold.Importantly,the GPA can be made to hold for any underlying microstructure,making the proposed framework widely applicable.展开更多
The so-called monodispersed colloids consist of particles that are uniform in shape and composition as well as narrow in size distribution. For fundamental researches, such as characteristics of electrical double laye...The so-called monodispersed colloids consist of particles that are uniform in shape and composition as well as narrow in size distribution. For fundamental researches, such as characteristics of electrical double layer at interface, adsorption and the stability with respect to coagulation, uniform colloidal particles have become handy tools for testing theories in these respects. It is the reproducibility of the properties of展开更多
The tunability of nonuniform reflection holographic filter is investigated theoretically and experimentally. It is shown that the reflection holographic filter has not only high optical density and narrow bandwidth, b...The tunability of nonuniform reflection holographic filter is investigated theoretically and experimentally. It is shown that the reflection holographic filter has not only high optical density and narrow bandwidth, but also good tunability. The coupled wave theoretical model for uniform medium is compared with the model for nonuniform medium. It is identified that the coincidence of the theoretical results of the nonuniform model with the experimental results are better than that of the uniform model.展开更多
BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amin...BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amino acids(AAAs:Tyrosine,tryptophan,phenylalanine)show high sensitivity and specificity in predicting diabetes in animals and predict T2DM 10-19 years before T2DM onset in clinical studies.However,improvement is needed to support its clinical utility.AIM To evaluate the effects of body mass index(BMI)and sex on BCAAs/AAAs in new-onset T2DM individuals with varying body weight.METHODS Ninety-seven new-onset T2DM patients(<12 mo)differing in BMI[normal weight(NW),n=33,BMI=22.23±1.60;overweight,n=42,BMI=25.9±1.07;obesity(OB),n=22,BMI=31.23±2.31]from the First People’s Hospital of Yunnan Province,Kunming,China,were studied.One-way and 2-way ANOVAs were conducted to determine the effects of BMI and sex on BCAAs/AAAs.RESULTS Fasting serum AAAs,BCAAs,glutamate,and alanine were greater and high-density lipoprotein(HDL)was lower(P<0.05,each)in OB-T2DM patients than in NW-T2DM patients,especially in male OB-T2DM patients.Arginine,histidine,leucine,methionine,and lysine were greater in male patients than in female patients.Moreover,histidine,alanine,glutamate,lysine,valine,methionine,leucine,isoleucine,tyrosine,phenylalanine,and tryptophan were significantly correlated with abdominal adiposity,body weight and BMI,whereas isoleucine,leucine and phenylalanine were negatively correlated with HDL.CONCLUSION Heterogeneously elevated amino acids,especially BCAAs/AAAs,across new-onset T2DM patients in differing BMI categories revealed a potentially skewed prediction of T2DM development.The higher BCAA/AAA levels in obese T2DM patients would support T2DM prediction in obese individuals,whereas the lower levels of BCAAs/AAAs in NW-T2DM individuals may underestimate T2DM risk in NW individuals.This potentially skewed T2DM prediction should be considered when BCAAs/AAAs are to be used as the T2DM predictor.展开更多
临床医生和放射诊断科医生对影像学的格式化报告和标准术语的要求正在不断增加。一项研究[1]发现，CT报告在对肺结节边缘和钙化表述上不统一。另一项研究[2]比较了Fleischner Society Glossary中列举的影像术语和它们常用医学词典中的...临床医生和放射诊断科医生对影像学的格式化报告和标准术语的要求正在不断增加。一项研究[1]发现，CT报告在对肺结节边缘和钙化表述上不统一。另一项研究[2]比较了Fleischner Society Glossary中列举的影像术语和它们常用医学词典中的一致性，包括国际疾病分类、标准参考医学术语和统一医学语言系统等，发现Fleischner术语应用率低，仅为3%-36%[3]。另一方面，研究提示对特殊疾病的标准影像学报告，如乳腺癌筛查报告可以改善患者治疗结果。因此希望对疑似胸腺瘤的前纵隔肿瘤制定标准的描述术语和提高这些术语的应用率，达到能促进临床医生和放射科医生之间的交流的目的，最终给患者治疗带来获益。除了制定统一的术语，报告中还应包含相关疾病知识，使之具有疾病特异性。美国放射医师协会制定了乳腺影像报告和数据系统，描述在钼靶和超声影像发现的乳腺病灶，发现影像报告结果与组织学结果具有相关性[4]。乳腺影像报告和数据系统提供一个对应各种病理类型的百分概率，并在临床上得到广泛应用[5]。一个相似的系统应用于甲状腺结节的超声评估，将这些结节分为高度恶性可能和低度恶性可能，指导适当的临床治疗，这个系统被称为甲状腺影像报告数据系统[6]。展开更多
Based on a pseudo-spectral large eddy simulation (LES) model, an LES model with an anisotropy turbulent kinetic energy (TKE) closure model and an explicit multi-stage third-order Runge-Kutta scheme is established. The...Based on a pseudo-spectral large eddy simulation (LES) model, an LES model with an anisotropy turbulent kinetic energy (TKE) closure model and an explicit multi-stage third-order Runge-Kutta scheme is established. The modeling and analysis show that the LES model can simulate the planetary boundary layer (PBL) with a uniform underlying surface under various stratifications very well. Then, similar to the description of a forest canopy, the drag term on momentum and the production term of TKE by subgrid city buildings are introduced into the LES equations to account for the area-averaged effect of the subgrid urban canopy elements and to simulate the meteorological fields of the urban boundary layer (UBL). Numerical experiments and comparison analysis show that: (1) the result from the LES of the UBL with a proposed formula for the drag coefficient is consistent and comparable with that from wind tunnel experiments and an urban subdomain scale model; (2) due to the effect of urban buildings, the wind velocity near the canopy is decreased, turbulence is intensified, TKE, variance, and momentum flux are increased, the momentum and heat flux at the top of the PBL are increased, and the development of the PBL is quickened; (3) the height of the roughness sublayer (RS) of the actual city buildings is the maximum building height (1.5-3 times the mean building height), and a constant flux layer (CFL) exists in the lower part of the UBL.展开更多
Helicobacter pylori (H. pylori) is an extremely common, yet underappreciated, pathogen that is able to alter host physiology and subvert the host immune response, allowing it to persist for the life of the host. H. py...Helicobacter pylori (H. pylori) is an extremely common, yet underappreciated, pathogen that is able to alter host physiology and subvert the host immune response, allowing it to persist for the life of the host. H. pylori is the primary cause of peptic ulcers and gastric cancer. In the United States, the annual cost associated with peptic ulcer disease is estimated to be $6 billion and gastric cancer kills over 700000 people per year globally. The prevalence of H. pylori infection remains high (> 50%) in much of the world, although the infection rates are dropping in some developed nations. The drop in H. pylori prevalence could be a double-edged sword, reducing the incidence of gastric diseases while increasing the risk of allergies and esophageal diseases. The list of diseases potentially caused by H. pylori continues to grow; however, mechanistic explanations of how H. pylori could contribute to extragastric diseases lag far behind clinical studies. A number of host factors and H. pylori virulence factors act in concert to determine which individuals are at the highest risk of disease. These include bacterial cytotoxins and polymorphisms in host genes responsible for directing the immune response. This review discusses the latest advances in H. pylori pathogenesis, diagnosis, and treatment. Up-to-date information on correlations between H. pylori and extragastric diseases is also provided.展开更多
Brain-derived neurotrophic factor(BDNF), which regulates neuronal survival, growth differentiation, and synapse formation, is known to be associated with depression and post-traumatic stress disorder(PTSD). However, t...Brain-derived neurotrophic factor(BDNF), which regulates neuronal survival, growth differentiation, and synapse formation, is known to be associated with depression and post-traumatic stress disorder(PTSD). However, the molecular mechanism for those mental disorders remains unknown. Studies have shown that BDNF is associated with PTSD risk and exaggerated startle reaction(a major arousal manifestation of PTSD) in United States military service members who were deployed during the wars in Iraq and Afghanistan. The frequency of the Met/Met in BDNF gene was greater among those with PTSD than those without PTSD. Among individuals who experienced fewer lifetime stressful events, the Met carriers have significantly higher total and startle scores on the PTSD Checklist than the Val/Val carriers. In addition, subjects with PTSD showed higher levels of BDNF in their peripheral blood plasma than the non-probable-PTSD controls. Increased BDNF levels and startle response were observed in both blood plasma and brain hippocampus by inescapable tail shock in rats. In this paper, we reviewed these data to discuss BDNF as a potential biomarker for PTSD risk and its possible roles in the onset of PTSD.展开更多
With improvements in personnel and vehicular body armor,robust casualty evacuation capabilities,and damage control resuscitation strategies,more combat casualties are surviving to reach higher levels of care throughou...With improvements in personnel and vehicular body armor,robust casualty evacuation capabilities,and damage control resuscitation strategies,more combat casualties are surviving to reach higher levels of care throughout the casualty evacuation system.As such,medical centers are becoming more accustomed to managing the deleterious late consequences of combat trauma related to the dysregulation of the immune system.In this review,we aim to highlight these late consequences and identify areas for future research and therapeutic strategies.Trauma leads to the dysregulation of both the innate and adaptive immune responses,which places the injured at risk for several late consequences,including delayed wound healing,late onset sepsis and infection,multi-organ dysfunction syndrome,and acute respiratory distress syndrome,which are significant for their association with the increased morbidity and mortality of wounded personnel.The mechanisms by which these consequences develop are complex but include an imbalance of the immune system leading to robust inflammatory responses,triggered by the presence of damage associated molecules and other immune-modifying agents following trauma.Treatment strategies to improve outcomes have been difficult to develop as the immunophenotype of injured personnel following trauma is variable,fluid and difficult to determine.As more information regarding the triggers that lead to immune dysfunction following trauma is elucidated,it may be possible to identify the immunophenotype of injured personnel and provide targeted treatments to reduce the late consequences of trauma,which are known to lead to significant morbidity and mortality.展开更多
Traumatic brain injury(TBI)is a leading cause of death and disability worldwide.Global assessments estimate that over 27 million cases of TBI occur annually,resulting in over 8 million years lived with disability(GBD ...Traumatic brain injury(TBI)is a leading cause of death and disability worldwide.Global assessments estimate that over 27 million cases of TBI occur annually,resulting in over 8 million years lived with disability(GBD 2016 Dementia Collaborators,2019).Over 30 clinical trials have failed to show efficacy in TBI,and patients are currently left without any promising therapeutic options(Villapol et al.,2015).The pathophysiology of TBI is commonly divided into primary and secondary injuries.Primary injury refers to the parenchymal damage that occurs as an immediate consequence of acute kinetic energy transfer to the brain(i.e.,membrane rupture,hemorrhage,axotomy,etc.).Secondary injury encompasses the deleterious molecular and cellular responses that occur in response to the primary injury in the minutes,hours or days following.The search for therapeutics that mitigate the effects of the secondary injury and/or assist endogenous repair processes remains a large focus of TBI research(Umschweif et al.,2014;Villapol et al.,2015;Janatpour et al.,2019).展开更多
AIM:To evaluate the contribution of the G-197A polymorphism in the interleukin-17(IL-17)promoter region to gastric cancer risk in an Iranian population.METHODS:We performed a case control study using samples from 161 ...AIM:To evaluate the contribution of the G-197A polymorphism in the interleukin-17(IL-17)promoter region to gastric cancer risk in an Iranian population.METHODS:We performed a case control study using samples from 161 individuals with gastric cancer and171 healthy controls.For each individual,the G-197A genotype was determined by restriction fragment length polymorphism analysis of polymerase chain reaction-amplified fragments.Statistical analyses were performed to determine whether any demographic or behavioral factors,infection with Helicobacter pylori(H.pylori),or a particular G-197A genotype was associated with gastric cancer risk.RESULTS:We found that the G-197A genotype wassignificantly associated with increased gastric cancer risk(P=0.001).Patients who were homozygous(AA)at position-197 were 2.9 times more likely to develop disease(95%CI:1.56-5.4;P=0.001).Furthermore,logistic regression analysis revealed that the presence of a single A allele increased the risk of gastric cancer up to 1.7-fold(95%CI:1.26-2.369;P=0.001).This association was observed for early stage gastric adenocarcinomas only,and was not linked to H.pylori infection.CONCLUSION:These results suggest that carrying one or more G-197A polymorphisms at position-197 in the IL-17 promoter region significantly increases gastric cancer risk in this patient population.展开更多
AIM： To investigate the association of the inducible ni- tric oxide synthetase （iNOS） C150T polymorphism with Helicobacter pylori （H. pylor/） infection and gastric can- cer （GC） risk in Iran. METHODS： In order...AIM： To investigate the association of the inducible ni- tric oxide synthetase （iNOS） C150T polymorphism with Helicobacter pylori （H. pylor/） infection and gastric can- cer （GC） risk in Iran. METHODS： In order to determine whether there was a correlation between iNOS genotype and GC in Iran, we conducted a case-control study using samples from 329 individuals. For each sample, the C150T ilVOS poly- morphism was genotyped by polymerase chain reaction （PCR） and restriction digestion. Patients were grouped by cancer presence, demographic and behavior charac- teristics, and/-/, pylori infection status. Statistical tests were conducted to determine whether any behavioral factors or a particular iNOS genotype was associated with GC in the study population. RESULTS： In this population, we found that smok- ing, hot beverage consumption, a familial history of GC and H. pylori infection status were significantly associated with GC development （P = 0.015, P 〈 0.001, P = 0.0034, and P 〈 0.015, respectively）. The distribution of the C150T ilVOS genotypes among the two study groups was not statistically significant alone, but was impacted by H. pylori infection status. When compared to the non-/-/, pylori infected group, cancer patients who had a heterozygous CT genotype and were also infected with H. pylori were 2.1 times more at risk of developing GC [odds ratio （OR） = 2.1, P = 0.03] while those with a homozygous TT genotype and infected with H. pylori were 5.0 times more at risk of developing GC （OR = 5.0, P = 0.029）. In contrast, this association was not seen in patients in the control group.CONCLUSION： ACT or TT polymorphism at position 150 in the iNO$ gene significantly increases the risk of GC and may be a marker for GC susceptibility.展开更多
文摘We consider a system of neutral equations with unbounded delay, and derive conditions on Liapunov functionals to ensure that the solutions are uniformly bounded and uniformly ultimately bounded.
文摘This article discusses the general boundary value problem for the nonlinear uniformly elliptic equation of second order in D (0.1) and the boundary condition,(0.2) in a multiply connected infinite domain D with the boundary T. The above boundary value problem is called Problem G. Problem G extends the work [8] in which the equation (0.1) includes a nonlinear lower term and the boundary condition (0.2) is more general. If the complex equation (0.1) and the boundary condition (0.2) meet certain assumptions, some solvability results for Problem G can be obtained. By using reduction to absurdity, we first discuss a priori estimates of solutions and solvability for a modified problem. Then we present results on solvability of Problem G.
文摘The nonpreemptive assignment of independent tasks to a system of m uniform processors isexamined with the objective of minimizing the makespan. Using r_m, the ratio of the fasest speed tothe slowest speed of the system, as a parameter, we assess the performance of LPT (largestprocessing time) schedule with respect to optimal schedules. It is shown thet the worst-case boundfor the ratio of the two schedule lengths is between
基金supported by the National Institute of Mental Health (NIH/NIMH)the National Institute of Neurological Disorders and Stroke(NIH/NINDS):Grants#R21 MH132136 to FSN and R01 MH123700 and R01 NS040701 to MLD
文摘There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).
基金supported by the intramural research program(IRP)of the Eunice Kennedy Shriver National Institute of Child Health and Human Development。
文摘The field of diffusion micro structural magnetic resonance(MR)aims to probe timedependent diffusion,i.e.,an ensemble-averaged mean-squared displacement that is not linear in time.This time-dependence contains rich information about the surrounding microenvironment.MR methods to measure time-dependent diffusion quantitatively,however,require either non-standard pulse sequences,such as oscillating gradients,or make non-physical assumptions,such as infinitely narrow gradient pulses.Here,we argue that standard spin echo and stimulated echo MR sequences can be used to probe directly.In particular,we propose a framework in which the log-signal ratio obtained from a pair of measurements with different inter-pulse spacingΔis proportional to the MSD between these twoΔvalues along the gradient direction x:-.The framework is quantitative for short,finite-duration gradient pulses and under the Gaussian phase approximation(GPA).To validate the framework,we consider onedimensional diffusion between impermeable,parallel planes,as well as periodicallyspaced,permeable planes.Excellent agreement is obtained between the estimation and the ground truth in the regime where the GPA is expected to hold.Importantly,the GPA can be made to hold for any underlying microstructure,making the proposed framework widely applicable.
文摘The so-called monodispersed colloids consist of particles that are uniform in shape and composition as well as narrow in size distribution. For fundamental researches, such as characteristics of electrical double layer at interface, adsorption and the stability with respect to coagulation, uniform colloidal particles have become handy tools for testing theories in these respects. It is the reproducibility of the properties of
文摘The tunability of nonuniform reflection holographic filter is investigated theoretically and experimentally. It is shown that the reflection holographic filter has not only high optical density and narrow bandwidth, but also good tunability. The coupled wave theoretical model for uniform medium is compared with the model for nonuniform medium. It is identified that the coincidence of the theoretical results of the nonuniform model with the experimental results are better than that of the uniform model.
基金Supported by the Open Project Grant for Clinical Medical Center of Yunnan Province,No.2019LCZXKF-NM03Medical Leader Training Grant,No.L-201624and Yunnan Province Ten Thousand Talents:“Medical Expert”grant,No.YNWR-MY-2019-020.
文摘BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amino acids(AAAs:Tyrosine,tryptophan,phenylalanine)show high sensitivity and specificity in predicting diabetes in animals and predict T2DM 10-19 years before T2DM onset in clinical studies.However,improvement is needed to support its clinical utility.AIM To evaluate the effects of body mass index(BMI)and sex on BCAAs/AAAs in new-onset T2DM individuals with varying body weight.METHODS Ninety-seven new-onset T2DM patients(<12 mo)differing in BMI[normal weight(NW),n=33,BMI=22.23±1.60;overweight,n=42,BMI=25.9±1.07;obesity(OB),n=22,BMI=31.23±2.31]from the First People’s Hospital of Yunnan Province,Kunming,China,were studied.One-way and 2-way ANOVAs were conducted to determine the effects of BMI and sex on BCAAs/AAAs.RESULTS Fasting serum AAAs,BCAAs,glutamate,and alanine were greater and high-density lipoprotein(HDL)was lower(P<0.05,each)in OB-T2DM patients than in NW-T2DM patients,especially in male OB-T2DM patients.Arginine,histidine,leucine,methionine,and lysine were greater in male patients than in female patients.Moreover,histidine,alanine,glutamate,lysine,valine,methionine,leucine,isoleucine,tyrosine,phenylalanine,and tryptophan were significantly correlated with abdominal adiposity,body weight and BMI,whereas isoleucine,leucine and phenylalanine were negatively correlated with HDL.CONCLUSION Heterogeneously elevated amino acids,especially BCAAs/AAAs,across new-onset T2DM patients in differing BMI categories revealed a potentially skewed prediction of T2DM development.The higher BCAA/AAA levels in obese T2DM patients would support T2DM prediction in obese individuals,whereas the lower levels of BCAAs/AAAs in NW-T2DM individuals may underestimate T2DM risk in NW individuals.This potentially skewed T2DM prediction should be considered when BCAAs/AAAs are to be used as the T2DM predictor.
文摘临床医生和放射诊断科医生对影像学的格式化报告和标准术语的要求正在不断增加。一项研究[1]发现，CT报告在对肺结节边缘和钙化表述上不统一。另一项研究[2]比较了Fleischner Society Glossary中列举的影像术语和它们常用医学词典中的一致性，包括国际疾病分类、标准参考医学术语和统一医学语言系统等，发现Fleischner术语应用率低，仅为3%-36%[3]。另一方面，研究提示对特殊疾病的标准影像学报告，如乳腺癌筛查报告可以改善患者治疗结果。因此希望对疑似胸腺瘤的前纵隔肿瘤制定标准的描述术语和提高这些术语的应用率，达到能促进临床医生和放射科医生之间的交流的目的，最终给患者治疗带来获益。除了制定统一的术语，报告中还应包含相关疾病知识，使之具有疾病特异性。美国放射医师协会制定了乳腺影像报告和数据系统，描述在钼靶和超声影像发现的乳腺病灶，发现影像报告结果与组织学结果具有相关性[4]。乳腺影像报告和数据系统提供一个对应各种病理类型的百分概率，并在临床上得到广泛应用[5]。一个相似的系统应用于甲状腺结节的超声评估，将这些结节分为高度恶性可能和低度恶性可能，指导适当的临床治疗，这个系统被称为甲状腺影像报告数据系统[6]。
基金The research was supported by the National Natural Science Foundation of China under Grant Nos.40333027 and 40075004.
文摘Based on a pseudo-spectral large eddy simulation (LES) model, an LES model with an anisotropy turbulent kinetic energy (TKE) closure model and an explicit multi-stage third-order Runge-Kutta scheme is established. The modeling and analysis show that the LES model can simulate the planetary boundary layer (PBL) with a uniform underlying surface under various stratifications very well. Then, similar to the description of a forest canopy, the drag term on momentum and the production term of TKE by subgrid city buildings are introduced into the LES equations to account for the area-averaged effect of the subgrid urban canopy elements and to simulate the meteorological fields of the urban boundary layer (UBL). Numerical experiments and comparison analysis show that: (1) the result from the LES of the UBL with a proposed formula for the drag coefficient is consistent and comparable with that from wind tunnel experiments and an urban subdomain scale model; (2) due to the effect of urban buildings, the wind velocity near the canopy is decreased, turbulence is intensified, TKE, variance, and momentum flux are increased, the momentum and heat flux at the top of the PBL are increased, and the development of the PBL is quickened; (3) the height of the roughness sublayer (RS) of the actual city buildings is the maximum building height (1.5-3 times the mean building height), and a constant flux layer (CFL) exists in the lower part of the UBL.
文摘Helicobacter pylori (H. pylori) is an extremely common, yet underappreciated, pathogen that is able to alter host physiology and subvert the host immune response, allowing it to persist for the life of the host. H. pylori is the primary cause of peptic ulcers and gastric cancer. In the United States, the annual cost associated with peptic ulcer disease is estimated to be $6 billion and gastric cancer kills over 700000 people per year globally. The prevalence of H. pylori infection remains high (> 50%) in much of the world, although the infection rates are dropping in some developed nations. The drop in H. pylori prevalence could be a double-edged sword, reducing the incidence of gastric diseases while increasing the risk of allergies and esophageal diseases. The list of diseases potentially caused by H. pylori continues to grow; however, mechanistic explanations of how H. pylori could contribute to extragastric diseases lag far behind clinical studies. A number of host factors and H. pylori virulence factors act in concert to determine which individuals are at the highest risk of disease. These include bacterial cytotoxins and polymorphisms in host genes responsible for directing the immune response. This review discusses the latest advances in H. pylori pathogenesis, diagnosis, and treatment. Up-to-date information on correlations between H. pylori and extragastric diseases is also provided.
基金Supported by Center for the Study of Traumatic Stress,Department of Psychiatry,Uniformed Services University of the Health Sciences
文摘Brain-derived neurotrophic factor(BDNF), which regulates neuronal survival, growth differentiation, and synapse formation, is known to be associated with depression and post-traumatic stress disorder(PTSD). However, the molecular mechanism for those mental disorders remains unknown. Studies have shown that BDNF is associated with PTSD risk and exaggerated startle reaction(a major arousal manifestation of PTSD) in United States military service members who were deployed during the wars in Iraq and Afghanistan. The frequency of the Met/Met in BDNF gene was greater among those with PTSD than those without PTSD. Among individuals who experienced fewer lifetime stressful events, the Met carriers have significantly higher total and startle scores on the PTSD Checklist than the Val/Val carriers. In addition, subjects with PTSD showed higher levels of BDNF in their peripheral blood plasma than the non-probable-PTSD controls. Increased BDNF levels and startle response were observed in both blood plasma and brain hippocampus by inescapable tail shock in rats. In this paper, we reviewed these data to discuss BDNF as a potential biomarker for PTSD risk and its possible roles in the onset of PTSD.
基金RJS was supported by National Institutes of Health grants,K08-GM117367.
文摘With improvements in personnel and vehicular body armor,robust casualty evacuation capabilities,and damage control resuscitation strategies,more combat casualties are surviving to reach higher levels of care throughout the casualty evacuation system.As such,medical centers are becoming more accustomed to managing the deleterious late consequences of combat trauma related to the dysregulation of the immune system.In this review,we aim to highlight these late consequences and identify areas for future research and therapeutic strategies.Trauma leads to the dysregulation of both the innate and adaptive immune responses,which places the injured at risk for several late consequences,including delayed wound healing,late onset sepsis and infection,multi-organ dysfunction syndrome,and acute respiratory distress syndrome,which are significant for their association with the increased morbidity and mortality of wounded personnel.The mechanisms by which these consequences develop are complex but include an imbalance of the immune system leading to robust inflammatory responses,triggered by the presence of damage associated molecules and other immune-modifying agents following trauma.Treatment strategies to improve outcomes have been difficult to develop as the immunophenotype of injured personnel following trauma is variable,fluid and difficult to determine.As more information regarding the triggers that lead to immune dysfunction following trauma is elucidated,it may be possible to identify the immunophenotype of injured personnel and provide targeted treatments to reduce the late consequences of trauma,which are known to lead to significant morbidity and mortality.
文摘Traumatic brain injury(TBI)is a leading cause of death and disability worldwide.Global assessments estimate that over 27 million cases of TBI occur annually,resulting in over 8 million years lived with disability(GBD 2016 Dementia Collaborators,2019).Over 30 clinical trials have failed to show efficacy in TBI,and patients are currently left without any promising therapeutic options(Villapol et al.,2015).The pathophysiology of TBI is commonly divided into primary and secondary injuries.Primary injury refers to the parenchymal damage that occurs as an immediate consequence of acute kinetic energy transfer to the brain(i.e.,membrane rupture,hemorrhage,axotomy,etc.).Secondary injury encompasses the deleterious molecular and cellular responses that occur in response to the primary injury in the minutes,hours or days following.The search for therapeutics that mitigate the effects of the secondary injury and/or assist endogenous repair processes remains a large focus of TBI research(Umschweif et al.,2014;Villapol et al.,2015;Janatpour et al.,2019).
基金Supported by The Mazandaran University of Medical Sciences,No.89-512
文摘AIM:To evaluate the contribution of the G-197A polymorphism in the interleukin-17(IL-17)promoter region to gastric cancer risk in an Iranian population.METHODS:We performed a case control study using samples from 161 individuals with gastric cancer and171 healthy controls.For each individual,the G-197A genotype was determined by restriction fragment length polymorphism analysis of polymerase chain reaction-amplified fragments.Statistical analyses were performed to determine whether any demographic or behavioral factors,infection with Helicobacter pylori(H.pylori),or a particular G-197A genotype was associated with gastric cancer risk.RESULTS:We found that the G-197A genotype wassignificantly associated with increased gastric cancer risk(P=0.001).Patients who were homozygous(AA)at position-197 were 2.9 times more likely to develop disease(95%CI:1.56-5.4;P=0.001).Furthermore,logistic regression analysis revealed that the presence of a single A allele increased the risk of gastric cancer up to 1.7-fold(95%CI:1.26-2.369;P=0.001).This association was observed for early stage gastric adenocarcinomas only,and was not linked to H.pylori infection.CONCLUSION:These results suggest that carrying one or more G-197A polymorphisms at position-197 in the IL-17 promoter region significantly increases gastric cancer risk in this patient population.
基金Supported by The Mazandaran University of Medical Sciences,No. 88-512
文摘AIM： To investigate the association of the inducible ni- tric oxide synthetase （iNOS） C150T polymorphism with Helicobacter pylori （H. pylor/） infection and gastric can- cer （GC） risk in Iran. METHODS： In order to determine whether there was a correlation between iNOS genotype and GC in Iran, we conducted a case-control study using samples from 329 individuals. For each sample, the C150T ilVOS poly- morphism was genotyped by polymerase chain reaction （PCR） and restriction digestion. Patients were grouped by cancer presence, demographic and behavior charac- teristics, and/-/, pylori infection status. Statistical tests were conducted to determine whether any behavioral factors or a particular iNOS genotype was associated with GC in the study population. RESULTS： In this population, we found that smok- ing, hot beverage consumption, a familial history of GC and H. pylori infection status were significantly associated with GC development （P = 0.015, P 〈 0.001, P = 0.0034, and P 〈 0.015, respectively）. The distribution of the C150T ilVOS genotypes among the two study groups was not statistically significant alone, but was impacted by H. pylori infection status. When compared to the non-/-/, pylori infected group, cancer patients who had a heterozygous CT genotype and were also infected with H. pylori were 2.1 times more at risk of developing GC [odds ratio （OR） = 2.1, P = 0.03] while those with a homozygous TT genotype and infected with H. pylori were 5.0 times more at risk of developing GC （OR = 5.0, P = 0.029）. In contrast, this association was not seen in patients in the control group.CONCLUSION： ACT or TT polymorphism at position 150 in the iNO$ gene significantly increases the risk of GC and may be a marker for GC susceptibility.
