Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Variou...Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Various molecular alterations are identified not only in gastric cancer (GC) but also in precancerous lesions. H. pylori treatment seems to improve AG and GIM, but still remains controversial. In contrast, many studies, including meta-analysis, show that H. pylori eradication reduces GC. Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H. pylori eradication. This indicates that these changes may be an important factor in the identification of high risk patients for cancer development. Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC. A randomized controlled trial from Japan concluded that prophylactic eradication of H. pylori after endoscopic resection should be used to prevent the development of metachronous GC, but recent retrospective studies did not show the tendency. Patients with precancerous lesions (molecular alterations) that do not reverse after H. pylori treatment, represent the “point of no return” and may be at high risk for the development of GC. Therefore, earlier H. pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions.展开更多
Aim:To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate th...Aim:To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate the protective effect of ascorbic acid.Methods:The testicular△^(5),3β-hydroxysteroid dehydrogenase(HSD),17β-HSD,peroxidase and catalase activities along with the levels of malondialdehyde(MDA)and conjugated dienes in testicular tissue were measured for the evaluation of testicular oxidative stress.The plasma testosterone(T)level was measured by immunoassay.Various germ cells at stageⅦof spermatogenic cycle were quantified from testicular stained sections.Results:Cyclophosphamide treatment results in a significant inhibition in the testicular△^(5),3β-HSD and 17β-HSD activities,a decrease in plasma T level and a diminution in the counts of various germ cells.Moreover,this treatment was also associated with a significant inhibition of the peroxidase and catalase activities along with high levels of MDA and conjugated dienes in the testis.All these changes were reversed by ascorbic acid co-administration.Conclusion:Cyclophosphamide treatment at the dosage used caused testicular gametogenic and androgenic disorders as well as induced testicular oxidative stress that can be reversed by ascorbic acid co-administration.展开更多
This paper describes the usefulness of renewable energy throughout the world to generate power. Renewable energy adds a remarkable scope in power system. Renewable energy sources act as the prime mover of a microgrid....This paper describes the usefulness of renewable energy throughout the world to generate power. Renewable energy adds a remarkable scope in power system. Renewable energy sources act as the prime mover of a microgrid. The Microgrid is a small network of power system with distributed generation (DG) units connected in parallel. The integration challenges of renewable energy sources and the control of microgrid are described in this paper. The varied nature of DG system produces voltage and frequency deviation. The unknown nature of the load produces un-modeled dynamics. This un-modeled dynamic introduces measurable effects on the performance of the microgrid. This paper investigates the performance of the microgrid against different scenarios. The voltage of the microgrid is controlled by using different controllers and their results are also investigated. The performance of controllers is investigated using MATLAB/Simulink SimPowerSystems.展开更多
Early involvement of gut is observed in Parkinson’s disease (PD) and symptoms such as constipation may precede motor symptoms. α-Synuclein pathology is extensively evident in the gut and appear...Early involvement of gut is observed in Parkinson’s disease (PD) and symptoms such as constipation may precede motor symptoms. α-Synuclein pathology is extensively evident in the gut and appears to follow a rostrocaudal gradient. The gut may act as the starting point of PD pathology with spread toward the central nervous system. This spread of the synuclein pathology raises the possibility of prion-like propagation in PD pathogenesis. Recently, the role of gut microbiota in PD pathogenesis has received attention and some phenotypic correlation has also been shown. The extensive involvement of the gut in PD even in its early stages has led to the evaluation of enteric α-synuclein as a possible biomarker of early PD. The clinical manifestations of gastrointestinal dysfunction in PD include malnutrition, oral and dental disorders, sialorrhea, dysphagia, gastroparesis, constipation, and defecatory dysfunction. These conditions are quite distressing for the patients and require relevant investigations and adequate management. Treatment usually involves both pharmacological and non-pharmacological measures. One important aspect of gut dysfunction is its contribution to the clinical fluctuations in PD. Dysphagia and gastroparesis lead to inadequate absorption of oral anti-PD medications. These lead to response fluctuations, particularly delayed-on and no-on, and there is significant relationship between levodopa pharmacokinetics and gastric emptying in patients with PD. Therefore, in such cases, alternative routes of administration or drug delivery systems may be required.展开更多
Rare earth metals （REMs） are a series of 17 elements that have widespread and unique applications in high technology, power generation, communications, and defense industries. These resources are also pivotal to eme...Rare earth metals （REMs） are a series of 17 elements that have widespread and unique applications in high technology, power generation, communications, and defense industries. These resources are also pivotal to emergent sustainable energy and car- bon alternative technologies. Recovery of REMs is interesting due to its high market prices along with various industrial applications. Conventional technologies, viz. precipitation, filtration, liquid-liquid extraction, solid-liquid extraction, ion exchange, super critical extraction, electrowinning, electrorefining, electroslag ref＇ming, etc., which have been developed for the recovery of REMs, are not economically attractive. Biosorption represents a biotechnological innovation as well as a cost effective excellent tool for the recovery of rare earth metals from aqueous solutions. A variety ofbiomaterials such as algae, fungi, bacteria, resin, activated carbon, etc., have been reported to serve as potential adsorbents for the recovery of REMs. The metal binding mechanisms, as well as the parameters in- fluencing the uptake of rare earth metals and isotherm modeling are presented here. This article provides an overview of past achievements and current scenario of the biosorption studies carried out using some promising biosorbents which could serve as an economical means for recovering REMs. The experimental findings reported by different workers will provide insights into this re- search frontier.展开更多
AIM： To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS： Sixty-eigh...AIM： To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS： Sixty-eight patients with severe alcoholic hepatitis （Maddrey score ≥ 32） received pentoxifylline （n = 34, group Ⅰ） or prednisolone （n = 34, group Ⅱ） for 28 d in a randomized double-blind controlled study, and subsequently in an open study （with a tapering dose of prednisolone） for a total of 3 mo, and were followed up over a period of 12 mo.RESULTS： Twelve patients in group Ⅱ died at the end of 3 mo in contrast to five patients in group Ⅰ. The probability of dying at the end of 3 mo was higher in group Ⅱ as compared to group Ⅰ （35.29% vs 14.71%, P = 0.04; log rank test）. Six patients in group I developed hepatorenal syndrome as compared to none in group Ⅰ. Pentoxifylline was associated with a significantly lower model for end-stage liver disease （MELD） score at the end of 28 d of therapy （15.53± 3.63 vs 17.78± 4.56, P=0.04）. Higher baseline Maddrey score was associated with increased mortality.CONCLUSION： Reduced mortality, improved risk-benefit profile and renoprotective effects of pentoxifylline compared with prednisolone suggest that pentoxifylline is superior to prednisolone for treatment of severe alcoholic hepatitis.展开更多
Diffusion weighted imaging(DWI) is a method of signal contrast generation based on the differences in Brownian motion. DWI is a method to evaluate the molecular function and micro-architecture of the human body. DWI s...Diffusion weighted imaging(DWI) is a method of signal contrast generation based on the differences in Brownian motion. DWI is a method to evaluate the molecular function and micro-architecture of the human body. DWI signal contrast can be quantified by apparent diffusion coefficient maps and it acts as a tool for treatment respon-se evaluation and assessment of disease progression. Ability to detect and quantify the anisotropy of diffusion leads to a new paradigm called diffusion tensor imaging(DTI). DTI is a tool for assessment of the organs with highly organised fibre structure. DWI forms an integral part of modern state-of-art magnetic resonance imaging and is indispensable in neuroimaging and oncology. DWI is a field that has been undergoing rapid technical evolution and its applications are increasing every day. This review article provides insights in to the evolution of DWI as a new imaging paradigm and provides a summary of current role of DWI in various disease processes.展开更多
Differentiating Crohn's disease(CD) and intestinal tuberculosis(ITB) has remained a dilemma for most of the clinicians in the developing world, which are endemic for ITB, and where the disease burden of inflammato...Differentiating Crohn's disease(CD) and intestinal tuberculosis(ITB) has remained a dilemma for most of the clinicians in the developing world, which are endemic for ITB, and where the disease burden of inflammatory bowel disease is on the rise. Although, there are certain clinical(diarrhea/hematochezia/perianal disease common in CD; fever/night sweats common in ITB), endoscopic(longitudinal/aphthous ulcers common in CD; transverse ulcers/patulous ileocaecal valve common in ITB), histologic(caseating/confluent/large granuloma common in ITB; microgranuloma common in CD), microbiologic(positive stain/culture for acid fast-bacillus in ITB), radiologic(long segment involvement/comb sign/skip lesions common in CD; necrotic lymph node/contiguous ileocaecal involvement common in ITB), and serologic differences between CD and ITB, the only exclusive features are caseation necrosis on biopsy, positive smear for acid-fast bacillus(AFB) and/or AFB culture, and necrotic lymph node on cross-sectional imaging in ITB. However,these exclusive features are limited by poor sensitivity, and this has led to the development of multiple multi-parametric predictive models. These models are also limited by complex formulae, small sample size and lack of validation across other populations. Several new parameters have come up including the latest Bayesian meta-analysis, enumeration of peripheral blood T-regulatory cells, and updated computed tomography based predictive score. However, therapeutic anti-tubercular therapy(ATT) trial, and subsequent clinical and endoscopic response to ATT is still required in a significant proportion of patients to establish the diagnosis. Therapeutic ATT trial is associated with a delay in the diagnosis of CD, and there is a need for better modalities for improved differentiation and reduction in the need for ATT trial.展开更多
Granulocyte-macrophage colony-stimulating factor （GM-CSF） is an important hematopoietic growth factor and immune modulator. GM-CSF also has profound effects on the functional activities of various circulating leukoc...Granulocyte-macrophage colony-stimulating factor （GM-CSF） is an important hematopoietic growth factor and immune modulator. GM-CSF also has profound effects on the functional activities of various circulating leukocytes. It is produced by a variety of cell types including T cells, macrophages, endothelial cells and fibroblasts upon receiving immune stimuli. Although GM-CSF is produced locally, it can act in a paracrine fashion to recruit circulating neutrophils, monocytes and lymphocytes to enhance their functions in host defense. Recent intensive investigations are centered on the application of GM-CSF as an immune adjuvant for its ability to increase dendritic cell （DC） maturation and function as well as macrophage activity. It is used clinically to treat neutropenia in cancer patients undergoing chemotherapy, in AIDS patients during therapy, and in patients after bone marrow transplantation. Interestingly, the hematopoietic system of GM-CSF-deficient mice appears to be normal; the most significant changes are in some specific T cell responses. Although molecular cloning of GM-CSF was carried out using cDNA library oft cells and it is well known that the T cells produce GM-CSF after activation, there is a lack of systematic investigation of this cytokine in production by T cells and its effect on T cell function. In this article, we will focus mainly on the immunobiology of GM-CSF in T cells.展开更多
Infectious diseases of poverty(IDoP)disproportionately affect the poorest population in the world and contribute to a cycle of poverty as a result of decreased productivity ensuing from long-term illness,disability,an...Infectious diseases of poverty(IDoP)disproportionately affect the poorest population in the world and contribute to a cycle of poverty as a result of decreased productivity ensuing from long-term illness,disability,and social stigma.In 2010,the global deaths from HIV/AIDS have increased to 1.5 million and malaria mortality rose to 1.17 million.Mortality from neglected tropical diseases rose to 152,000,while tuberculosis killed 1.2 million people that same year.Substantial regional variations exist in the distribution of these diseases as they are primarily concentrated in rural areas of Sub-Saharan Africa,Asia,and Latin America,with geographic overlap and high levels of co-infection.Evidence-based interventions exist to prevent and control these diseases,however,the coverage still remains low with an emerging challenge of antimicrobial resistance.Therefore,community-based delivery platforms are increasingly being advocated to ensure sustainability and combat co-infections.Because of the high morbidity and mortality burden of these diseases,especially in resource-poor settings,it is imperative to conduct a systematic review to identify strategies to prevent and control these diseases.Therefore,we attempted to evaluate the effectiveness of one of these strategies,that is community-based delivery for the prevention and treatment of IDoP.In this paper,we describe the burden,epidemiology,and potential interventions for IDoP.In subsequent papers of this series,we describe the analytical framework and the methodology used to guide the systematic reviews,and report the findings and interpretations of our analyses of the impact of community-based strategies on individual IDoPs.展开更多
The corrosion behavior of Mg,AZ31 and AZ91 has been evaluated in 3.5%NaCl solution using weight loss,electrochemical polarization and impedance measurements.Corrosion rate derived from the weight losses demonstrated t...The corrosion behavior of Mg,AZ31 and AZ91 has been evaluated in 3.5%NaCl solution using weight loss,electrochemical polarization and impedance measurements.Corrosion rate derived from the weight losses demonstrated the occurrence of steeply fast corrosion reaction on AZ91 alloy after three hours of immersion,indicating the start of galvanic corrosion.An increase of corrosion rate with immersion time was also observed for AZ31 but with lesser extent than AZ91 alloy.Whereas Mg metals showed a decrease of corrosion rate with immersion time,suggesting the formation of a protective layer on their surfaces.In contrast,the corrosion current density(I_(corr))derived from the Tafel plots,exhibited their corrosion resistances in order of Mg>AZ91>AZ31.Electrochemical charge transfer resistance(R_(ct))and double layer capacitance measured by electrochemical impedance spectroscopy(EIS),are well in accordance with the measured I_(corr).EIS measurements with time and microstructural examination of the corroded and uncorroded samples are helpful in elucidation of results measured by electrochemical polarization.展开更多
Formation control is a cooperative control concept in which multiple autonomous underwater mobile robots are deployed for a group motion and/or control mission. This paper presents a brief review on various cooperativ...Formation control is a cooperative control concept in which multiple autonomous underwater mobile robots are deployed for a group motion and/or control mission. This paper presents a brief review on various cooperative search and formation control strategies for multiple autonomous underwater vehicles （AUV） based on literature reported till date. Various cooperative and formation control schemes for collecting huge amount of data based on formation regulation control and formation tracking control are discussed. To address the challenge of detecting AUV failure in the fleet, communication issues, collision and obstacle avoidance are also taken into attention. Stability analysis of the feasible formation is also presented. This paper may be intended to serve as a convenient reference for the further research on formation control of multiple underwater mobile robots.展开更多
INTRODUCTIONThe 1990’s have brought a significant promise and the hopefor a better and brighter future in the new millennium forpatients with inflammatory bowel disease(IBD).A betterunderstanding of the pathophysiolo...INTRODUCTIONThe 1990’s have brought a significant promise and the hopefor a better and brighter future in the new millennium forpatients with inflammatory bowel disease(IBD).A betterunderstanding of the pathophysiology of IBD symptoms hasled to newer treatment modalities and streamlining oftherapy for specific subsets of patients.展开更多
Localization is one of the fundamental problems in wireless sensor networks （WSNs）, since locations of the sensor nodes are critical to both network operations and most application level tasks. Although the GPS base...Localization is one of the fundamental problems in wireless sensor networks （WSNs）, since locations of the sensor nodes are critical to both network operations and most application level tasks. Although the GPS based localization schemes can be used to determine node locations within a few meters, the cost of GPS devices and non-availability of GPS signals in confined environments prevent their use in large scale sensor networks. There exists an extensive body of research that aims at obtaining locations as well as spatial relations of nodes in WSNs without requiring specialized hardware and/or employing only a limited number of anchors that are aware of their own locations. In this paper, we present a comprehensive survey on sensor localization in WSNs covering motivations, problem formulations, solution approaches and performance summary. Future research issues will also be discussed.展开更多
Depression is a chronic,recurring and potentially life-threatening illness that affects up to 20%of the population across the world.Despite its prevalence and considerable impact on human,little is known about its pat...Depression is a chronic,recurring and potentially life-threatening illness that affects up to 20%of the population across the world.Despite its prevalence and considerable impact on human,little is known about its pathogenesis.One of the major reasons is the restricted availability of validated animal models due to the absence of consensus on the pathology and etiology of depression.Besides,some core symptoms such as depressed mood,feeling of worthlessness,and recurring thoughts of death or suicide,are impossible to be modeled on laboratory animals.Currently,the criteria for identifying animal models of depression rely on either of the 2 principles：actions of known antidepressants and responses to stress.This review mainly focuses on the most widely used animal models of depression,including learned helplessness,chronic mild stress,and social defeat paradigms.Also,the behavioral tests for screening antidepressants,such as forced swimming test and tail suspension test,are also discussed.The advantages and major drawbacks of each model are evaluated.In prospective,new techniques that will be beneficial for developing novel animal models or detecting depression are discussed.展开更多
The underwater path planning problem deals with finding an optimal or sub-optimal route between an origin point and a termination point in marine environments.The underwater environment is still considered as a great ...The underwater path planning problem deals with finding an optimal or sub-optimal route between an origin point and a termination point in marine environments.The underwater environment is still considered as a great challenge for the path planning of autonomous underwater vehicles(AUVs)because of its hostile and dynamic nature.The major constraints for path planning are limited data transmission capability,power and sensing technology available for underwater operations.The sea environment is subjected to a large set of challenging factors classified as atmospheric,coastal and gravitational.Based on whether the impact of these factors can be approximated or not,the underwater environment can be characterized as predictable and unpredictable respectively.The classical path planning algorithms based on artificial intelligence assume that environmental conditions are known apriori to the path planner.But the current path planning algorithms involve continual interaction with the environment considering the environment as dynamic and its effect cannot be predicted.Path planning is necessary for many applications involving AUVs.These are based upon planning safety routes with minimum energy cost and computation overheads.This review is intended to summarize various path planning strategies for AUVs on the basis of characterization of underwater environments as predictable and unpredictable.The algorithms employed in path planning of single AUV and multiple AUVs are reviewed in the light of predictable and unpredictable environments.展开更多
Flexible triboelectric nanogenerators (TENGs)-based pressure sensors are very essential for the wide-range applications, comprising wearable healthcare systems, intuitive human-device interfaces, electronic-skin (e-sk...Flexible triboelectric nanogenerators (TENGs)-based pressure sensors are very essential for the wide-range applications, comprising wearable healthcare systems, intuitive human-device interfaces, electronic-skin (e-skin), and artificial intelligence. Most of conventional fabrication methods used to produce high-performance TENGs involve plasma treatment, photolithography, printing, and electro-deposition. However, these fabrication techniques are expensive, multi-step, time-consuming and not suitable for mass production, which are the main barriers for efficient and cost-effective commercialization of TENGs. Here, we established a highly reliable scheme for the fabrication of a novel eco-friendly, low cost, and TENG-based pressure sensor (TEPS) designed for usage in self-powered-human gesture detection (SP-HGD) likewise wearable healthcare applications. The sensors with microstructured electrodes performed well with high sensitivity (7.697 kPa^-1), a lower limit of detection (~ 1 Pa), faster response time (< 9.9 ms), and highly stable over > 4,000 compression-releasing cycles. The proposed method is suitable for the adaptable fabrication of TEPS at an extremely low cost with possible applications in self-powered systems, especially e-skin and healthcare applications.展开更多
All retinoids, which can be natural and synthetic, are chemically related to vitamin A. Both natural and synthetic retinoids use specific nuclear receptors such as retinoic acid receptors and retinoid X receptors to a...All retinoids, which can be natural and synthetic, are chemically related to vitamin A. Both natural and synthetic retinoids use specific nuclear receptors such as retinoic acid receptors and retinoid X receptors to activate specific signaling pathways in the cells. Retinoic acid signaling is extremely important in the central nervous system. Impairment of retinoic acid signaling pathways causes severe pathological processes in the central nervous system, especially in the adult brain. Retinoids have major roles in neural patterning, differentiation, axon outgrowth in normal development, and function of the brain. Impaired retinoic acid signaling results in neuroinflammation, oxidative stress, mitochondrial malfunction, and neurodegeneration leading to progressive Alzheimer’s disease, which is pathologically characterized by extra-neuronal accumulation of amyloid plaques(aggregated amyloid-beta) and intra-neurofibrillary tangles(hyperphosphorylated tau protein) in the temporal lobe of the brain. Alzheimer’s disease is the most common cause of dementia and loss of memory in old adults. Inactive cholinergic neurotransmission is responsible for cognitive deficits in Alzheimer’s disease patients. Deficiency or deprivation of retinoic acid in mice is associated with loss of spatial learning and memory. Retinoids inhibit expression of chemokines and neuroinflammatory cytokines in microglia and astrocytes, which are activated in Alzheimer’s disease. Stimulation of retinoic acid receptors and retinoid X receptors slows down accumulation of amyloids, reduces neurodegeneration, and thereby prevents pathogenesis of Alzheimer’s disease in mice. In this review, we described chemistry and biochemistry of some natural and synthetic retinoids and potentials of retinoids for prevention of neuroinflammation and neurodegeneration in Alzheimer’s disease.展开更多
AIM:The study was initiated to evaluate the reactogenicity and immunogenicity of a recombinant hepatitis B vaccine in age group >40 years and to study the response of a single booster dose in primary non-responders...AIM:The study was initiated to evaluate the reactogenicity and immunogenicity of a recombinant hepatitis B vaccine in age group >40 years and to study the response of a single booster dose in primary non-responders to the hepatitis B vaccination. METHODS:A total of 102 volunteers without markers of hepatitis B infection (negative for HBsAg,anti-HBc antibody, HBeAg and anti-HBs antibody) received 20μg of recombinant HB vaccine intramuscularly at 0,1,and 6 months.Anti HBs titers were evaluated by a quantitative Elisa kit at 90 and 210 days.A booster dose of 20μg HB vaccine was given after 6 months of the 3^(rd) vaccine dose to the 15 non- responders and anti-HBs titers were measured after i month. RESULTS:Seroprotection (anti-HBs GMT^3 10 IU/L) was achieved in 85.3 % (87/102) volunteers.The mean GMT titers of the vaccine responders was 136.1 IU/L.Of the seroprotected individuals,there were 32.4% (33/102) hyporesponders (anti- HBs titers <10-99 mIU/ml) and 52.9% (54/102) were responders (anti-HBs titers >100 IU/L).All the non-responders (15/15) responded to a single dose of the booster dose of recombinant HB vaccine and their mean anti-HBs antibody titers were more than 100.5 mIU/ml after the booster dose. CONCLUSION:Recombinant hepatitis B vaccine offers good seroprotection in the age group >40 years and has a good safety profile.A single booster dose after 6 months in primary non-responders leads to good seroprotective anti-HBs antibody titers.However,larger population based studies are needed to evaluate the role of a booster dose in selected group of non-responders and whether such an approach will be cost effective.展开更多
基金Supported by Grant,NIDDK,RO1DK63618 to KMD from the National Institutes of Health,Bethesda,MD
文摘Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Various molecular alterations are identified not only in gastric cancer (GC) but also in precancerous lesions. H. pylori treatment seems to improve AG and GIM, but still remains controversial. In contrast, many studies, including meta-analysis, show that H. pylori eradication reduces GC. Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H. pylori eradication. This indicates that these changes may be an important factor in the identification of high risk patients for cancer development. Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC. A randomized controlled trial from Japan concluded that prophylactic eradication of H. pylori after endoscopic resection should be used to prevent the development of metachronous GC, but recent retrospective studies did not show the tendency. Patients with precancerous lesions (molecular alterations) that do not reverse after H. pylori treatment, represent the “point of no return” and may be at high risk for the development of GC. Therefore, earlier H. pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions.
基金The authors gratefully acknowledge the financial assistance from the Major Research Project(Project No.F-3/50/99 dated 3l-3-99)provided by the University Grants Commission(UGC),New Delhi,India
文摘Aim:To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate the protective effect of ascorbic acid.Methods:The testicular△^(5),3β-hydroxysteroid dehydrogenase(HSD),17β-HSD,peroxidase and catalase activities along with the levels of malondialdehyde(MDA)and conjugated dienes in testicular tissue were measured for the evaluation of testicular oxidative stress.The plasma testosterone(T)level was measured by immunoassay.Various germ cells at stageⅦof spermatogenic cycle were quantified from testicular stained sections.Results:Cyclophosphamide treatment results in a significant inhibition in the testicular△^(5),3β-HSD and 17β-HSD activities,a decrease in plasma T level and a diminution in the counts of various germ cells.Moreover,this treatment was also associated with a significant inhibition of the peroxidase and catalase activities along with high levels of MDA and conjugated dienes in the testis.All these changes were reversed by ascorbic acid co-administration.Conclusion:Cyclophosphamide treatment at the dosage used caused testicular gametogenic and androgenic disorders as well as induced testicular oxidative stress that can be reversed by ascorbic acid co-administration.
文摘This paper describes the usefulness of renewable energy throughout the world to generate power. Renewable energy adds a remarkable scope in power system. Renewable energy sources act as the prime mover of a microgrid. The Microgrid is a small network of power system with distributed generation (DG) units connected in parallel. The integration challenges of renewable energy sources and the control of microgrid are described in this paper. The varied nature of DG system produces voltage and frequency deviation. The unknown nature of the load produces un-modeled dynamics. This un-modeled dynamic introduces measurable effects on the performance of the microgrid. This paper investigates the performance of the microgrid against different scenarios. The voltage of the microgrid is controlled by using different controllers and their results are also investigated. The performance of controllers is investigated using MATLAB/Simulink SimPowerSystems.
文摘Early involvement of gut is observed in Parkinson’s disease (PD) and symptoms such as constipation may precede motor symptoms. α-Synuclein pathology is extensively evident in the gut and appears to follow a rostrocaudal gradient. The gut may act as the starting point of PD pathology with spread toward the central nervous system. This spread of the synuclein pathology raises the possibility of prion-like propagation in PD pathogenesis. Recently, the role of gut microbiota in PD pathogenesis has received attention and some phenotypic correlation has also been shown. The extensive involvement of the gut in PD even in its early stages has led to the evaluation of enteric α-synuclein as a possible biomarker of early PD. The clinical manifestations of gastrointestinal dysfunction in PD include malnutrition, oral and dental disorders, sialorrhea, dysphagia, gastroparesis, constipation, and defecatory dysfunction. These conditions are quite distressing for the patients and require relevant investigations and adequate management. Treatment usually involves both pharmacological and non-pharmacological measures. One important aspect of gut dysfunction is its contribution to the clinical fluctuations in PD. Dysphagia and gastroparesis lead to inadequate absorption of oral anti-PD medications. These lead to response fluctuations, particularly delayed-on and no-on, and there is significant relationship between levodopa pharmacokinetics and gastric emptying in patients with PD. Therefore, in such cases, alternative routes of administration or drug delivery systems may be required.
文摘Rare earth metals （REMs） are a series of 17 elements that have widespread and unique applications in high technology, power generation, communications, and defense industries. These resources are also pivotal to emergent sustainable energy and car- bon alternative technologies. Recovery of REMs is interesting due to its high market prices along with various industrial applications. Conventional technologies, viz. precipitation, filtration, liquid-liquid extraction, solid-liquid extraction, ion exchange, super critical extraction, electrowinning, electrorefining, electroslag ref＇ming, etc., which have been developed for the recovery of REMs, are not economically attractive. Biosorption represents a biotechnological innovation as well as a cost effective excellent tool for the recovery of rare earth metals from aqueous solutions. A variety ofbiomaterials such as algae, fungi, bacteria, resin, activated carbon, etc., have been reported to serve as potential adsorbents for the recovery of REMs. The metal binding mechanisms, as well as the parameters in- fluencing the uptake of rare earth metals and isotherm modeling are presented here. This article provides an overview of past achievements and current scenario of the biosorption studies carried out using some promising biosorbents which could serve as an economical means for recovering REMs. The experimental findings reported by different workers will provide insights into this re- search frontier.
文摘AIM： To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS： Sixty-eight patients with severe alcoholic hepatitis （Maddrey score ≥ 32） received pentoxifylline （n = 34, group Ⅰ） or prednisolone （n = 34, group Ⅱ） for 28 d in a randomized double-blind controlled study, and subsequently in an open study （with a tapering dose of prednisolone） for a total of 3 mo, and were followed up over a period of 12 mo.RESULTS： Twelve patients in group Ⅱ died at the end of 3 mo in contrast to five patients in group Ⅰ. The probability of dying at the end of 3 mo was higher in group Ⅱ as compared to group Ⅰ （35.29% vs 14.71%, P = 0.04; log rank test）. Six patients in group I developed hepatorenal syndrome as compared to none in group Ⅰ. Pentoxifylline was associated with a significantly lower model for end-stage liver disease （MELD） score at the end of 28 d of therapy （15.53± 3.63 vs 17.78± 4.56, P=0.04）. Higher baseline Maddrey score was associated with increased mortality.CONCLUSION： Reduced mortality, improved risk-benefit profile and renoprotective effects of pentoxifylline compared with prednisolone suggest that pentoxifylline is superior to prednisolone for treatment of severe alcoholic hepatitis.
文摘Diffusion weighted imaging(DWI) is a method of signal contrast generation based on the differences in Brownian motion. DWI is a method to evaluate the molecular function and micro-architecture of the human body. DWI signal contrast can be quantified by apparent diffusion coefficient maps and it acts as a tool for treatment respon-se evaluation and assessment of disease progression. Ability to detect and quantify the anisotropy of diffusion leads to a new paradigm called diffusion tensor imaging(DTI). DTI is a tool for assessment of the organs with highly organised fibre structure. DWI forms an integral part of modern state-of-art magnetic resonance imaging and is indispensable in neuroimaging and oncology. DWI is a field that has been undergoing rapid technical evolution and its applications are increasing every day. This review article provides insights in to the evolution of DWI as a new imaging paradigm and provides a summary of current role of DWI in various disease processes.
文摘Differentiating Crohn's disease(CD) and intestinal tuberculosis(ITB) has remained a dilemma for most of the clinicians in the developing world, which are endemic for ITB, and where the disease burden of inflammatory bowel disease is on the rise. Although, there are certain clinical(diarrhea/hematochezia/perianal disease common in CD; fever/night sweats common in ITB), endoscopic(longitudinal/aphthous ulcers common in CD; transverse ulcers/patulous ileocaecal valve common in ITB), histologic(caseating/confluent/large granuloma common in ITB; microgranuloma common in CD), microbiologic(positive stain/culture for acid fast-bacillus in ITB), radiologic(long segment involvement/comb sign/skip lesions common in CD; necrotic lymph node/contiguous ileocaecal involvement common in ITB), and serologic differences between CD and ITB, the only exclusive features are caseation necrosis on biopsy, positive smear for acid-fast bacillus(AFB) and/or AFB culture, and necrotic lymph node on cross-sectional imaging in ITB. However,these exclusive features are limited by poor sensitivity, and this has led to the development of multiple multi-parametric predictive models. These models are also limited by complex formulae, small sample size and lack of validation across other populations. Several new parameters have come up including the latest Bayesian meta-analysis, enumeration of peripheral blood T-regulatory cells, and updated computed tomography based predictive score. However, therapeutic anti-tubercular therapy(ATT) trial, and subsequent clinical and endoscopic response to ATT is still required in a significant proportion of patients to establish the diagnosis. Therapeutic ATT trial is associated with a delay in the diagnosis of CD, and there is a need for better modalities for improved differentiation and reduction in the need for ATT trial.
文摘Granulocyte-macrophage colony-stimulating factor （GM-CSF） is an important hematopoietic growth factor and immune modulator. GM-CSF also has profound effects on the functional activities of various circulating leukocytes. It is produced by a variety of cell types including T cells, macrophages, endothelial cells and fibroblasts upon receiving immune stimuli. Although GM-CSF is produced locally, it can act in a paracrine fashion to recruit circulating neutrophils, monocytes and lymphocytes to enhance their functions in host defense. Recent intensive investigations are centered on the application of GM-CSF as an immune adjuvant for its ability to increase dendritic cell （DC） maturation and function as well as macrophage activity. It is used clinically to treat neutropenia in cancer patients undergoing chemotherapy, in AIDS patients during therapy, and in patients after bone marrow transplantation. Interestingly, the hematopoietic system of GM-CSF-deficient mice appears to be normal; the most significant changes are in some specific T cell responses. Although molecular cloning of GM-CSF was carried out using cDNA library oft cells and it is well known that the T cells produce GM-CSF after activation, there is a lack of systematic investigation of this cytokine in production by T cells and its effect on T cell function. In this article, we will focus mainly on the immunobiology of GM-CSF in T cells.
文摘Infectious diseases of poverty(IDoP)disproportionately affect the poorest population in the world and contribute to a cycle of poverty as a result of decreased productivity ensuing from long-term illness,disability,and social stigma.In 2010,the global deaths from HIV/AIDS have increased to 1.5 million and malaria mortality rose to 1.17 million.Mortality from neglected tropical diseases rose to 152,000,while tuberculosis killed 1.2 million people that same year.Substantial regional variations exist in the distribution of these diseases as they are primarily concentrated in rural areas of Sub-Saharan Africa,Asia,and Latin America,with geographic overlap and high levels of co-infection.Evidence-based interventions exist to prevent and control these diseases,however,the coverage still remains low with an emerging challenge of antimicrobial resistance.Therefore,community-based delivery platforms are increasingly being advocated to ensure sustainability and combat co-infections.Because of the high morbidity and mortality burden of these diseases,especially in resource-poor settings,it is imperative to conduct a systematic review to identify strategies to prevent and control these diseases.Therefore,we attempted to evaluate the effectiveness of one of these strategies,that is community-based delivery for the prevention and treatment of IDoP.In this paper,we describe the burden,epidemiology,and potential interventions for IDoP.In subsequent papers of this series,we describe the analytical framework and the methodology used to guide the systematic reviews,and report the findings and interpretations of our analyses of the impact of community-based strategies on individual IDoPs.
文摘The corrosion behavior of Mg,AZ31 and AZ91 has been evaluated in 3.5%NaCl solution using weight loss,electrochemical polarization and impedance measurements.Corrosion rate derived from the weight losses demonstrated the occurrence of steeply fast corrosion reaction on AZ91 alloy after three hours of immersion,indicating the start of galvanic corrosion.An increase of corrosion rate with immersion time was also observed for AZ31 but with lesser extent than AZ91 alloy.Whereas Mg metals showed a decrease of corrosion rate with immersion time,suggesting the formation of a protective layer on their surfaces.In contrast,the corrosion current density(I_(corr))derived from the Tafel plots,exhibited their corrosion resistances in order of Mg>AZ91>AZ31.Electrochemical charge transfer resistance(R_(ct))and double layer capacitance measured by electrochemical impedance spectroscopy(EIS),are well in accordance with the measured I_(corr).EIS measurements with time and microstructural examination of the corroded and uncorroded samples are helpful in elucidation of results measured by electrochemical polarization.
文摘Formation control is a cooperative control concept in which multiple autonomous underwater mobile robots are deployed for a group motion and/or control mission. This paper presents a brief review on various cooperative search and formation control strategies for multiple autonomous underwater vehicles （AUV） based on literature reported till date. Various cooperative and formation control schemes for collecting huge amount of data based on formation regulation control and formation tracking control are discussed. To address the challenge of detecting AUV failure in the fleet, communication issues, collision and obstacle avoidance are also taken into attention. Stability analysis of the feasible formation is also presented. This paper may be intended to serve as a convenient reference for the further research on formation control of multiple underwater mobile robots.
文摘INTRODUCTIONThe 1990’s have brought a significant promise and the hopefor a better and brighter future in the new millennium forpatients with inflammatory bowel disease(IBD).A betterunderstanding of the pathophysiology of IBD symptoms hasled to newer treatment modalities and streamlining oftherapy for specific subsets of patients.
基金supported by the National Science Foundation (No.CNS-0721951,IIS-0326505)the Air Force Office of Scientific Research(AFOSR) (No.FA9550-08-1-0260)+1 种基金the Texas Advanced Research Program (ARP) (No.14-748779)the Research I Foundation grant of IIT-Kanpur,and Department of Science and Technology,Government of India under Indo-Trento Program for Advanced Research
文摘Localization is one of the fundamental problems in wireless sensor networks （WSNs）, since locations of the sensor nodes are critical to both network operations and most application level tasks. Although the GPS based localization schemes can be used to determine node locations within a few meters, the cost of GPS devices and non-availability of GPS signals in confined environments prevent their use in large scale sensor networks. There exists an extensive body of research that aims at obtaining locations as well as spatial relations of nodes in WSNs without requiring specialized hardware and/or employing only a limited number of anchors that are aware of their own locations. In this paper, we present a comprehensive survey on sensor localization in WSNs covering motivations, problem formulations, solution approaches and performance summary. Future research issues will also be discussed.
文摘Depression is a chronic,recurring and potentially life-threatening illness that affects up to 20%of the population across the world.Despite its prevalence and considerable impact on human,little is known about its pathogenesis.One of the major reasons is the restricted availability of validated animal models due to the absence of consensus on the pathology and etiology of depression.Besides,some core symptoms such as depressed mood,feeling of worthlessness,and recurring thoughts of death or suicide,are impossible to be modeled on laboratory animals.Currently,the criteria for identifying animal models of depression rely on either of the 2 principles：actions of known antidepressants and responses to stress.This review mainly focuses on the most widely used animal models of depression,including learned helplessness,chronic mild stress,and social defeat paradigms.Also,the behavioral tests for screening antidepressants,such as forced swimming test and tail suspension test,are also discussed.The advantages and major drawbacks of each model are evaluated.In prospective,new techniques that will be beneficial for developing novel animal models or detecting depression are discussed.
文摘The underwater path planning problem deals with finding an optimal or sub-optimal route between an origin point and a termination point in marine environments.The underwater environment is still considered as a great challenge for the path planning of autonomous underwater vehicles(AUVs)because of its hostile and dynamic nature.The major constraints for path planning are limited data transmission capability,power and sensing technology available for underwater operations.The sea environment is subjected to a large set of challenging factors classified as atmospheric,coastal and gravitational.Based on whether the impact of these factors can be approximated or not,the underwater environment can be characterized as predictable and unpredictable respectively.The classical path planning algorithms based on artificial intelligence assume that environmental conditions are known apriori to the path planner.But the current path planning algorithms involve continual interaction with the environment considering the environment as dynamic and its effect cannot be predicted.Path planning is necessary for many applications involving AUVs.These are based upon planning safety routes with minimum energy cost and computation overheads.This review is intended to summarize various path planning strategies for AUVs on the basis of characterization of underwater environments as predictable and unpredictable.The algorithms employed in path planning of single AUV and multiple AUVs are reviewed in the light of predictable and unpredictable environments.
文摘Flexible triboelectric nanogenerators (TENGs)-based pressure sensors are very essential for the wide-range applications, comprising wearable healthcare systems, intuitive human-device interfaces, electronic-skin (e-skin), and artificial intelligence. Most of conventional fabrication methods used to produce high-performance TENGs involve plasma treatment, photolithography, printing, and electro-deposition. However, these fabrication techniques are expensive, multi-step, time-consuming and not suitable for mass production, which are the main barriers for efficient and cost-effective commercialization of TENGs. Here, we established a highly reliable scheme for the fabrication of a novel eco-friendly, low cost, and TENG-based pressure sensor (TEPS) designed for usage in self-powered-human gesture detection (SP-HGD) likewise wearable healthcare applications. The sensors with microstructured electrodes performed well with high sensitivity (7.697 kPa^-1), a lower limit of detection (~ 1 Pa), faster response time (< 9.9 ms), and highly stable over > 4,000 compression-releasing cycles. The proposed method is suitable for the adaptable fabrication of TEPS at an extremely low cost with possible applications in self-powered systems, especially e-skin and healthcare applications.
基金supported in part by an award from the Soy Health Research Program(SHRP,United Soybean Board,Chesterfield,MO,USA)(to SKR)a grant(SCIRF-2015-I-01) from South Carolina Spinal Cord Injury Research Fund(Columbia,SC,USA)(to SKR)earlier R01 grants(CA-091460,and NS-057811)(to SKR) from the National Institutes of Health(Bethesda,MD,USA)
文摘All retinoids, which can be natural and synthetic, are chemically related to vitamin A. Both natural and synthetic retinoids use specific nuclear receptors such as retinoic acid receptors and retinoid X receptors to activate specific signaling pathways in the cells. Retinoic acid signaling is extremely important in the central nervous system. Impairment of retinoic acid signaling pathways causes severe pathological processes in the central nervous system, especially in the adult brain. Retinoids have major roles in neural patterning, differentiation, axon outgrowth in normal development, and function of the brain. Impaired retinoic acid signaling results in neuroinflammation, oxidative stress, mitochondrial malfunction, and neurodegeneration leading to progressive Alzheimer’s disease, which is pathologically characterized by extra-neuronal accumulation of amyloid plaques(aggregated amyloid-beta) and intra-neurofibrillary tangles(hyperphosphorylated tau protein) in the temporal lobe of the brain. Alzheimer’s disease is the most common cause of dementia and loss of memory in old adults. Inactive cholinergic neurotransmission is responsible for cognitive deficits in Alzheimer’s disease patients. Deficiency or deprivation of retinoic acid in mice is associated with loss of spatial learning and memory. Retinoids inhibit expression of chemokines and neuroinflammatory cytokines in microglia and astrocytes, which are activated in Alzheimer’s disease. Stimulation of retinoic acid receptors and retinoid X receptors slows down accumulation of amyloids, reduces neurodegeneration, and thereby prevents pathogenesis of Alzheimer’s disease in mice. In this review, we described chemistry and biochemistry of some natural and synthetic retinoids and potentials of retinoids for prevention of neuroinflammation and neurodegeneration in Alzheimer’s disease.
文摘AIM:The study was initiated to evaluate the reactogenicity and immunogenicity of a recombinant hepatitis B vaccine in age group >40 years and to study the response of a single booster dose in primary non-responders to the hepatitis B vaccination. METHODS:A total of 102 volunteers without markers of hepatitis B infection (negative for HBsAg,anti-HBc antibody, HBeAg and anti-HBs antibody) received 20μg of recombinant HB vaccine intramuscularly at 0,1,and 6 months.Anti HBs titers were evaluated by a quantitative Elisa kit at 90 and 210 days.A booster dose of 20μg HB vaccine was given after 6 months of the 3^(rd) vaccine dose to the 15 non- responders and anti-HBs titers were measured after i month. RESULTS:Seroprotection (anti-HBs GMT^3 10 IU/L) was achieved in 85.3 % (87/102) volunteers.The mean GMT titers of the vaccine responders was 136.1 IU/L.Of the seroprotected individuals,there were 32.4% (33/102) hyporesponders (anti- HBs titers <10-99 mIU/ml) and 52.9% (54/102) were responders (anti-HBs titers >100 IU/L).All the non-responders (15/15) responded to a single dose of the booster dose of recombinant HB vaccine and their mean anti-HBs antibody titers were more than 100.5 mIU/ml after the booster dose. CONCLUSION:Recombinant hepatitis B vaccine offers good seroprotection in the age group >40 years and has a good safety profile.A single booster dose after 6 months in primary non-responders leads to good seroprotective anti-HBs antibody titers.However,larger population based studies are needed to evaluate the role of a booster dose in selected group of non-responders and whether such an approach will be cost effective.
