Linear quadratic regulator(LQR) and proportional-integral-derivative(PID) control methods, which are generally used for control of linear dynamical systems, are used in this paper to control the nonlinear dynamical sy...Linear quadratic regulator(LQR) and proportional-integral-derivative(PID) control methods, which are generally used for control of linear dynamical systems, are used in this paper to control the nonlinear dynamical system. LQR is one of the optimal control techniques, which takes into account the states of the dynamical system and control input to make the optimal control decisions.The nonlinear system states are fed to LQR which is designed using a linear state-space model. This is simple as well as robust. The inverted pendulum, a highly nonlinear unstable system, is used as a benchmark for implementing the control methods. Here the control objective is to control the system such that the cart reaches a desired position and the inverted pendulum stabilizes in the upright position. In this paper, the modeling and simulation for optimal control design of nonlinear inverted pendulum-cart dynamic system using PID controller and LQR have been presented for both cases of without and with disturbance input. The Matlab-Simulink models have been developed for simulation and performance analysis of the control schemes. The simulation results justify the comparative advantage of LQR control method.展开更多
Traumatic injury to the pancreas is rare and difficult to diagnose.In contrast,traumatic injuries to the liver,spleen and kidney are common and are usually identified with ease by imaging modalities.Pancreatic injurie...Traumatic injury to the pancreas is rare and difficult to diagnose.In contrast,traumatic injuries to the liver,spleen and kidney are common and are usually identified with ease by imaging modalities.Pancreatic injuries are usually subtle to identify by different diagnostic imaging modalities,and these injuries are often overlooked in cases with extensive multiorgan trauma.The most evident findings of pancreatic injury are posttraumatic pancreatitis with blood,edema,and soft tissue infiltration of the anterior pararenal space.The alterations of post-traumatic pancreatitis may not be visualized within several hours following trauma as they are time dependent.Delayed diagnoses of traumatic pancreatic injuries are associated with high morbidity and mortality.Imaging plays an important role in diagnosis of pancreatic injuries because early recognition of the disruption of the main pancreatic duct is important.We reviewed our experience with the use of various imaging modalities for diagnosis of blunt pancreatic trauma.展开更多
Magnesium is one of the largely available elements in the earth’s crust. It has a low structural density with high specific strength. This unique material property has forced an increase in the use of magnesium and i...Magnesium is one of the largely available elements in the earth’s crust. It has a low structural density with high specific strength. This unique material property has forced an increase in the use of magnesium and its alloys in various applications pertaining to industrial sector,automobiles, aerospace and biomedical. Since magnesium is a highly reactive metal, it is prone to higher rate of corrosion as compared to its counterparts. Thus, it is essential to analyze the corrosion behavior of magnesium and its alloys in its applications. An appropriate process is to be followed in the design and development of magnesium alloys which overcome the limitations of magnesium and enhance the desired material properties in accordance to their applications. This review paper summarizes the importance of magnesium and its material properties. The influence of various alloying elements on the mechanical properties of magnesium is reviewed. The broad classification of Mg alloys and their behavioral trends are detailed. The corrosion behavior of magnesium and the influence of corrosion products on the material characteristics of magnesium, in aqueous medium, are discussed. The manufacturing techniques of magnesium alloys along with the secondary techniques are also covered. The various applications and the limitations of magnesium in these applications are covered. A complete section is dedicated towards detailing the recent trends of magnesium(Mg) alloys, i.e., the biodegradable nature and applications of Mg alloys. The influence of biocorrosion on Mg alloys and techniques to overcome it have been deliberated. This paper provides a thorough review on recent developments of magnesium with respect to engineering applications.展开更多
Brain metabolism is an energy intensive phenomenon involving a wide spectrum of chemical intermediaries. Various injury states have a detrimental effect on the biochemical processes involved in the homeostatic and ele...Brain metabolism is an energy intensive phenomenon involving a wide spectrum of chemical intermediaries. Various injury states have a detrimental effect on the biochemical processes involved in the homeostatic and electrophysiological properties of the brain. The biochemical markers of brain injury are a recent addition in the armamentarium of neuro-clinicians and are being increasingly used in the routine management of neuropathological entities such as traumatic brain injury, stroke, subarachnoid haemorrhage and intracranial space occupying lesions. These markers are increasingly being used in assessing severity as well as in predicting the prognostic course of neuro-pathological lesions. S-100 protein, neuron specific enolase, creatinine phosphokinase isoenzyme BB and myelin basic protein are some of the biochemical markers which have been proven to have prognostic and clinical value in the brain injury. While S-100, glial fibrillary acidic protein and ubiquitin C terminal hydrolase are early biomarkers of neuronal injury and have the potential to aid in clinical decisionmaking in the initial management of patients presenting with an acute neuronal crisis, the other biomarkers are of value in predicting long-term complications and prognosis in such patients. In recent times cerebral microdialysis has established itself as a novel way of monitoring brain tissue biochemical metabolites such as glucose, lactate, pyruvate, glutamate and glycerol while small non-coding RNAs have presented themselves as potential markers of brain injury for future.展开更多
Objective:To evaluate antidiabetic and antioxidant potential of Hybanthus enneaspermus in different models.Methods:The oral glucose tolerance test(OGTT) and normoglycemic effect of alcoholic extract of Hybanthus ennea...Objective:To evaluate antidiabetic and antioxidant potential of Hybanthus enneaspermus in different models.Methods:The oral glucose tolerance test(OGTT) and normoglycemic effect of alcoholic extract of Hybanthus enneaspermus(AHE) were evaluated at a dose of 125,250 and 500mg/kg p.o.while hypoglycemic activity and effect on body weight were tested at 250 and 500 mg/kg p.o.per day for 21 days in Streptozotocin(STZ) induced diabetic rats.Further,glucose uptake by hemidiaphram was also evaluated.The total polyphenolic and flavonoid were determined and their correlation with various antioxidant assays was also determined.Results:The results showed high level of phenolic content in AHE.AHE also exhibited higher total antioxidant capacity,good reducing power and a significant scavenger of reactive oxygen species like DPPH radical,nitric oxide,hydrogen peroxide and deoxyribose.Furthermore there was a significant increase in the body weight and decrease in the blood glucose level on treatment with the AHE.AHE increased glucose uptake on isolated rat hemi-diaphragm compared to control group.Conclusions:AHE reduce blood glucose level in STZ-induced diabetic model.It does not show significant effect in normoglycemic study but showes significant effect in OGT.AHE has significant antioxidant activity,which may be attributed to high phenolic content.展开更多
AIM: To investigate the cellular defects by analyzing the (Th1/Th2) cytokine levels in vaccine responders and non-responders. METHODS: Peripheral blood mononuclear cell (PBMC) from responders and non-responders were s...AIM: To investigate the cellular defects by analyzing the (Th1/Th2) cytokine levels in vaccine responders and non-responders. METHODS: Peripheral blood mononuclear cell (PBMC) from responders and non-responders were stimulated with or with out recombinant HBsAg or PHA. Broad spectrum of cytokines viz (Th1) IFN-γ, IL-2, TNF-α, IL-12 and (Th2) IL-10, IL-4 were measured after in vitro stimulation with recombinant HBsAg and were compared with respective antibody titers. RESULTS: A significant decrease (P = 0.001) in Th1 and Th2 cytokines namely, IL-2, INF-γ, TNF-α and IL-10in non-responders was observed. The level of IL-4 was not significant between the three groups. Furthermore, despite a strong Th1 and Th2 cytokine response, the level of IL-12 was elevated in high-responders compared to other groups (P = 0.001) and demonstrated a positive correlation with anti-HBs titers and Th1 cytokine response. CONCLUSION: Our findings suggest that unrespon-siveness to recombinant hepatitis B vaccines (rHB) is multifactorial, including specific failure of antigen presentation or the lack of both T helper Th1 and Th2 response.展开更多
Abdominal tuberculosis is an increasingly common disease that poses diagnostic challenge,as the nonspecific features of the disease which may lead to diagnostic delays and development of complications.This condition i...Abdominal tuberculosis is an increasingly common disease that poses diagnostic challenge,as the nonspecific features of the disease which may lead to diagnostic delays and development of complications.This condition is regarded as a great mimicker of other abdominal pathology.A high index of suspicion is an important factor in early diagnosis.Abdominal involvement mayoccur in the gastrointestinal tract,peritoneum,lymphnodes or solid viscera.Various investigative methods have been used to aid in the diagnosis of abdominal tuberculosis.Early diagnosis and initiation of antituberculous therapy and surgical treatment are essential to prevent morbidity and mortality.Most of the patients respond very well to standard antitubercular therapy and surgery is required only in a minority of cases.Imaging plays an important role in diagnosis of abdominal tuberculosis because early recognition of this condition is important.We reviewed our experience with the findings on various imaging modalities for diagnosis of this potentially treatable disease.展开更多
AIM:To evaluate the effect of hepatitis B virus (HBV) infection on liver metastasis of colorectal cancer.METHODS:A total of 1298 colorectal cancer patients were recruited from January 2001 to March 2005 in this study....AIM:To evaluate the effect of hepatitis B virus (HBV) infection on liver metastasis of colorectal cancer.METHODS:A total of 1298 colorectal cancer patients were recruited from January 2001 to March 2005 in this study.Enzyme-linked immunosorbent assay was used to test serum HBV markers for colorectal cancer.Patients were divided into study (infection) group and control (non-infection) group.Clinical features of patients in two groups were compared.RESULTS:Liver metastasis was found in 319 out of the 1298 colorectal cancer patients.The incidence of liver metastasis was significantly lower in study group than in control group (14.2% vs 28.2%,P < 0.01).HBV infection significantly decreased the risk of liver metastasis [hazard ratio (HR):0.50,95% confidence interval (95% CI):0.38-0.66],but the incidence of extrahepatic metastasis was significantly higher in study group than in control group (31.9% vs 17.0%,P < 0.01).The HR was the lowest in chronic hepatitis B group (HR:0.29,95% CI:0.12-0.72).The number of liver metastatic lesions was significantly less in study group than in control group with a higher surgical resection rate.However,no significant difference was found in survival rate between the two groups (P=0.95).CONCLUSION:HBV infection decreases the risk of liver metastasis in patients with colorectal cancer and elevates the surgical resection rate of liver metastatic lesions.展开更多
Harmine,a beta-carboline alkaloid,is widely distributed in the plants,marine creatures,insects, mammalians as well as in human tissues and body fluids.Harmine was originally isolated from seeds of Peganum harmal in 18...Harmine,a beta-carboline alkaloid,is widely distributed in the plants,marine creatures,insects, mammalians as well as in human tissues and body fluids.Harmine was originally isolated from seeds of Peganum harmal in 1847 having a core indole structure and a pyridine ring.Harmine has various types of pharmacological activities such as antimicrobial,antifungal,antitumor,cytotoxic, antiplasmodial,antioxidaant,antimutagenic,antigenotoxic and hallucinogenic properties.It acts on gamma-aminobutyric acid type A and monoamine oxidase A or B receptor,enhances insulin sensitivity and also produces vasorelaxant effect.Harmine prevents bone loss by suppressing osteoclastogenesis.The current review gives an overview on pharmacological activity and analytical techniques of harmine,which may be useful for researcheres to explore the hidden potential of harmine and and will also help in developing new drugs for the treatment of various diseases.展开更多
Although beneficial in acute and chronic pain management, the use of local anaesthetics is limited by itsduration of action and the dose dependent adverse effects on the cardiac and central nervous system. Adjuvants o...Although beneficial in acute and chronic pain management, the use of local anaesthetics is limited by itsduration of action and the dose dependent adverse effects on the cardiac and central nervous system. Adjuvants or additives are often used with local anaesthetics for its synergistic effect by prolonging the duration of sensory-motor block and limiting the cumulative dose requirement of local anaesthetics. The armamentarium of local anesthetic adjuvants have evolved over time from classical opioids to a wide array of drugs spanning several groups and varying mechanisms of action. A large array of opioids ranging from morphine, fentanyl and sufentanyl to hydromorphone, buprenorphine and tramadol has been used with varying success. However, their use has been limited by their adverse effect like respiratory depression, nausea, vomiting and pruritus, especially with its neuraxial use. Epinephrine potentiates the local anesthetics by its antinociceptive properties mediated by alpha-2 adrenoreceptor activation along with its vasoconstrictive properties limiting the systemic absorption of local anesthetics. Alpha 2 adrenoreceptor antagonists like clonidine and dexmedetomidine are one of the most widely used class of local anesthetic adjuvants. Other drugs like steroids(dexamethasone), anti-inflammatory agents(parecoxib and lornoxicam), midazolam, ketamine, magnesium sulfate and neostigmine have also been used with mixed success. The concern regarding the safety profile of these adjuvants is due to its potential neurotoxicity and neurological complications which necessitate further research in this direction. Current research is directed towards a search for agents and techniques which would prolong local anaesthetic action without its deleterious effects. This includes novel approaches like use of charged molecules to produce local anaesthetic action(tonicaine and n butyl tetracaine), new age delivery mechanisms for prolonged bioavailability(liposomal, microspheres and cyclodextrin systems) and further studies with 展开更多
AIM: To investigate -765G > C COX-2 polymorphism and H pylori infection in patients with gastric adenocarcinoma, peptic ulcer disease (PUD) and non- ulcer dyspepsia (NUD). METHODS: We enrolled 348 adult patients (6...AIM: To investigate -765G > C COX-2 polymorphism and H pylori infection in patients with gastric adenocarcinoma, peptic ulcer disease (PUD) and non- ulcer dyspepsia (NUD). METHODS: We enrolled 348 adult patients (62 gastric adenocarcinoma, 45 PUD and 241 NUD) undergoing upper gastrointestinal endoscopy at two referral centers between September, 2002 and May, 2007. H pylori infection was diagnosed when any of the four tests (RUT, culture, histopathology and PCR) were positive. Genotyping for -765G > C polymorphism of COX-2 was performed by PCR-RFLP analysis. RESULTS: Frequency of C carrier had significantassociation with gastric adenocarcinoma as compared to NUD [77.4% vs 29%, P < 0.001, odds ratio (OR) 8.20; 95% confidence interval (95% CI), 4.08-16.47] and PUD (77.4% vs 31.1%, P < 0.001; OR 8.04; 95% CI, 3.25-19.90). Risk of gastric adenocarcinoma was significantly higher in patients having C carrier with (OR 7.83; 95% CI 3.09-19.85) and without H pylori infection (OR 7.06; 95% CI, 2.61-19.09). Patients with C carrier and H pylori infection had significant risk for the development of PUD (P < 0.001; OR 5.65; 95% CI, 2.07-15.34). CONCLUSION: -765G > C COX-2 polymorphism with or without H pylori could be a marker for genetic susceptibility to gastric adenocarcinoma. COX-2 polymorphism in presence of H pylori infection might be useful in predicting the risk of PUD.展开更多
Chronic haemorrhagic radiation proctitis(CHRP) is a difficult problem faced by the patients following radiation for pelvic malignancy. There is no standardtreatment for this condition, but many methods of treatment ar...Chronic haemorrhagic radiation proctitis(CHRP) is a difficult problem faced by the patients following radiation for pelvic malignancy. There is no standardtreatment for this condition, but many methods of treatment are available. The aim of this study was to review the literature to see whether there is an improvement in the available evidence in comparison with previously published systematic reviews in treating patients with CHRP. The Pub Med/Medline database and Google Scholar search was selectively searched. Studies, which treated patients with rectal bleeding due to chronic radiation proctitis or CHRP, were included. Seventy studies were finally selected out of which 14 were randomized controlled clinical trials. Though these studies could not be compared, it could be seen that there was an improvement in the methodology of the studies. There was an objective assessment of symptoms, signs and an objective assessment of outcomes. But, still, there were only a few studies that looked into the quality of life following treatment of CHRP. To increase recruitment to trials, a national registry of cases with established late radiation toxicity would facilitate the further improvement of such studies. Some of the conclusions that could be reached based on the available evidence are 4% formalin should be the first line treatment for patients with CHRP. Formalin and argon plasma coagulation(APC) are equally effective, but formalin is better for severe disease. Refractory patients, not responding to formalin or APC, need to be referred for hyperbaric oxygen therapy or surgery. Radio-frequency ablation is a promising modality that needs to be studied further in randomized trials.展开更多
Helicobacter pylori(H. pylori) infection is highly prevalent in human,affecting nearly half of the world's population; however,infection remains asymptomatic in majority of population. During its co-existence with...Helicobacter pylori(H. pylori) infection is highly prevalent in human,affecting nearly half of the world's population; however,infection remains asymptomatic in majority of population. During its co-existence with humans,H. pylori has evolved various strategies to maintain a mild gastritis and limit the immune response of host. On the other side,presence of H.pylori is also associated with increased risk for the development of various gastric pathologies including gastric cancer(GC). A complex combination of host genetics,environmental agents,and bacterial virulence factors are considered to determine the susceptibility as well as the severity of outcome in a subset of individuals. GC is one of the most common cancers and considered as the third most common cause of cancer related death worldwide. Many studies had proved H. pylori as an important risk factor in the development of non-cardia GC. Although both H. pylori infection and GC are showing decreasing trends in the developed world,they still remain a major threat to human population in the developing countries. The current review attempts to highlight recent progress in the field of research on H. pylori induced GC and aims to provide brief insight into H. pylori pathogenesis,the role of major virulence factors of H. pylori that modulates the host environment and transform the normal gastric epithelium to neoplastic one. This review also emphasizes on the mechanistic understanding of how colonization and various virulence attributes of H. pylori as well as the host innate and adaptive immune responses modulate the diverse signaling pathways that leads to different disease outcomes including GC.展开更多
Herbal medicines, mainly of plant source, are invaluable source for the discovery of new therapeutic agents for all sorts of human ailments. The complex pathogenesis of stroke and multifactorial effect of herbal medic...Herbal medicines, mainly of plant source, are invaluable source for the discovery of new therapeutic agents for all sorts of human ailments. The complex pathogenesis of stroke and multifactorial effect of herbal medicine and their active constituents may suggest the promising future of natural medicine for stroke treatment. Anti-oxidant, anti-inflammatory, anti-apoptotic, neuroprotective and vascular protective effect of herbal medicines are believed to be efficacious in stroke treatment. Herbs typically have fewer reported side effects than allopathic medicine, and may be safer to use over longer period of time. Herbal medicines are believed to be more effective for the longstanding health complaints, such as stroke. Several medicinal plants and their active constituents show the promising results in laboratory research. However failure in transformation of laboratory animal research to the clinical trials has created huge challenge for the use of herbal medicine in stroke. Until and unless scientifically comprehensive evidence of the efficacy and safety of herbal medicine in ischemic stroke patients is available, efforts should be made to continue implementing treatment strategies of proven effectiveness. More consideration should be paid to natural compounds that can have extensive therapeutic time windows, perfect pharmacological targets with few side effects. Herbal medicine has excellent prospective for the treatment of ischemic stroke, but a lot of effort should be invested to transform the success of animal research to human use.展开更多
Nature is a rich source of medicinal plants and their products that are useful for treatment of various diseases and disorders. Momordica charantia, commonly known as bitter melon or bitter gourd, is one of such plant...Nature is a rich source of medicinal plants and their products that are useful for treatment of various diseases and disorders. Momordica charantia, commonly known as bitter melon or bitter gourd, is one of such plants known for its biological activities used in traditional system of medicines. This plant is cultivated in all over the world, including tropical areas of Asia, Amazon, east Africa, and the Caribbean and used as a vegetable as well as folk medicine. All parts of the plant, including the fruit, are commonly consumed and cooked with different vegetables, stir-fried, stuffed or used in small quantities in soups or beans to give a slightly bitter flavor and taste. The plant is reported to possess anti-oxidant, anti-inflammatory, anti-cancer, anti-diabetic, anti-bacterial, anti-obesity, and immunomodulatory activities. The plant extract inhibits cancer cell growth by inducing apoptosis, cell cycle arrest, autophagy and inhibiting cancer stem cells. The plant is rich in bioactive chemical constituents like cucurbitane type triterpenoids, triterpene glycosides, phenolic acids, flavonoids, essential oils, saponins, fatty acids, and proteins. Some of the isolated compounds （Kuguacin J, Karaviloside XI, Kuguaglycoside C, Momordicoside Q-U, Charantin, a-eleostearic acid） and proteins （a-Momorcharin, RNase MC2, MAP30） possess potent biological activity. In the present review, we are summarizing the anti-oxidant, anti-inflammatory, and anti-cancer activities of Momordica charantia along with a short account of important chemical constituents, providing a basis for establishing detail biological activities of the plant and developing novel drug molecules based on the active chemical constituents.展开更多
Vasopressors are routinely used to counteract hypotension after neuraxial anesthesia in Obstetrics. The understanding of the mechanism of hypotension and the choice of vasopressor has evolved over the years to a point...Vasopressors are routinely used to counteract hypotension after neuraxial anesthesia in Obstetrics. The understanding of the mechanism of hypotension and the choice of vasopressor has evolved over the years to a point where phenylephrine has become the preferred vasopressor. Due to the absence of definitive evidence showing absolute clinical benefit of one over the other, especially in emergency and high-risk Cesarean sections, our choice of phenylephrine over the other vasopressors like mephentermine, metaraminol, and ephedrine is guided by indirect evidence on fetalacid-base status. This review article evaluates the present day evidence on the various vasopressors used in obstetric anesthesia today.展开更多
Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly este...Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly esteemed source of medicine therefore,they have become a growing part of modern,high-tech medicine.In view of the above aspects the present review provides profiles of plants(65 species) with hypoglycaemic properties,available through literature source from various database with proper categorization according to the parts used,mode of reduction in blood glucose(insulinomimetic or insulin secretagugues activity) and active phyloconsliluents having insulin mimetics activity.From the review it was suggested that,plant showing hypoglycemic potential mainly belongs to the family Leguminoseae,Lamiaceae,Liliaceae,Cucurbitaceae, Asteraceae,Moraceae,Rosaceae and Araliaceae.The most active plants are Allium sativum. Gymnema sylvestre,Citrullus colocynthis,Trigonella foenum greacum,Momordica charantia and Ficuts bengalensis.The review describes some new bioactive drugs and isolated compounds from plants such as roseoside,epigallocatechin gallate,beta-pyrazol-1-ylalanine,cinchonain Ib,leucocyandin 3-O-beta-d-galactosyl cellobioside,leucopelargonidin-3- O-alpha-L rhamuoside,glycyrrhetinic acid,dehydrotrametenolic acid,strictinin,isostrictinin,pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents.Thus,from the review majorly,the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols,flavonoida, terpenoids,coumarins and other constituents which show reduction in blood glucose levels.The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.展开更多
文摘Linear quadratic regulator(LQR) and proportional-integral-derivative(PID) control methods, which are generally used for control of linear dynamical systems, are used in this paper to control the nonlinear dynamical system. LQR is one of the optimal control techniques, which takes into account the states of the dynamical system and control input to make the optimal control decisions.The nonlinear system states are fed to LQR which is designed using a linear state-space model. This is simple as well as robust. The inverted pendulum, a highly nonlinear unstable system, is used as a benchmark for implementing the control methods. Here the control objective is to control the system such that the cart reaches a desired position and the inverted pendulum stabilizes in the upright position. In this paper, the modeling and simulation for optimal control design of nonlinear inverted pendulum-cart dynamic system using PID controller and LQR have been presented for both cases of without and with disturbance input. The Matlab-Simulink models have been developed for simulation and performance analysis of the control schemes. The simulation results justify the comparative advantage of LQR control method.
文摘Traumatic injury to the pancreas is rare and difficult to diagnose.In contrast,traumatic injuries to the liver,spleen and kidney are common and are usually identified with ease by imaging modalities.Pancreatic injuries are usually subtle to identify by different diagnostic imaging modalities,and these injuries are often overlooked in cases with extensive multiorgan trauma.The most evident findings of pancreatic injury are posttraumatic pancreatitis with blood,edema,and soft tissue infiltration of the anterior pararenal space.The alterations of post-traumatic pancreatitis may not be visualized within several hours following trauma as they are time dependent.Delayed diagnoses of traumatic pancreatic injuries are associated with high morbidity and mortality.Imaging plays an important role in diagnosis of pancreatic injuries because early recognition of the disruption of the main pancreatic duct is important.We reviewed our experience with the use of various imaging modalities for diagnosis of blunt pancreatic trauma.
文摘Magnesium is one of the largely available elements in the earth’s crust. It has a low structural density with high specific strength. This unique material property has forced an increase in the use of magnesium and its alloys in various applications pertaining to industrial sector,automobiles, aerospace and biomedical. Since magnesium is a highly reactive metal, it is prone to higher rate of corrosion as compared to its counterparts. Thus, it is essential to analyze the corrosion behavior of magnesium and its alloys in its applications. An appropriate process is to be followed in the design and development of magnesium alloys which overcome the limitations of magnesium and enhance the desired material properties in accordance to their applications. This review paper summarizes the importance of magnesium and its material properties. The influence of various alloying elements on the mechanical properties of magnesium is reviewed. The broad classification of Mg alloys and their behavioral trends are detailed. The corrosion behavior of magnesium and the influence of corrosion products on the material characteristics of magnesium, in aqueous medium, are discussed. The manufacturing techniques of magnesium alloys along with the secondary techniques are also covered. The various applications and the limitations of magnesium in these applications are covered. A complete section is dedicated towards detailing the recent trends of magnesium(Mg) alloys, i.e., the biodegradable nature and applications of Mg alloys. The influence of biocorrosion on Mg alloys and techniques to overcome it have been deliberated. This paper provides a thorough review on recent developments of magnesium with respect to engineering applications.
文摘Brain metabolism is an energy intensive phenomenon involving a wide spectrum of chemical intermediaries. Various injury states have a detrimental effect on the biochemical processes involved in the homeostatic and electrophysiological properties of the brain. The biochemical markers of brain injury are a recent addition in the armamentarium of neuro-clinicians and are being increasingly used in the routine management of neuropathological entities such as traumatic brain injury, stroke, subarachnoid haemorrhage and intracranial space occupying lesions. These markers are increasingly being used in assessing severity as well as in predicting the prognostic course of neuro-pathological lesions. S-100 protein, neuron specific enolase, creatinine phosphokinase isoenzyme BB and myelin basic protein are some of the biochemical markers which have been proven to have prognostic and clinical value in the brain injury. While S-100, glial fibrillary acidic protein and ubiquitin C terminal hydrolase are early biomarkers of neuronal injury and have the potential to aid in clinical decisionmaking in the initial management of patients presenting with an acute neuronal crisis, the other biomarkers are of value in predicting long-term complications and prognosis in such patients. In recent times cerebral microdialysis has established itself as a novel way of monitoring brain tissue biochemical metabolites such as glucose, lactate, pyruvate, glutamate and glycerol while small non-coding RNAs have presented themselves as potential markers of brain injury for future.
基金Supported by University Grant Commision New Delhi India(No:IT/DEV/08-09/3252/L)
文摘Objective:To evaluate antidiabetic and antioxidant potential of Hybanthus enneaspermus in different models.Methods:The oral glucose tolerance test(OGTT) and normoglycemic effect of alcoholic extract of Hybanthus enneaspermus(AHE) were evaluated at a dose of 125,250 and 500mg/kg p.o.while hypoglycemic activity and effect on body weight were tested at 250 and 500 mg/kg p.o.per day for 21 days in Streptozotocin(STZ) induced diabetic rats.Further,glucose uptake by hemidiaphram was also evaluated.The total polyphenolic and flavonoid were determined and their correlation with various antioxidant assays was also determined.Results:The results showed high level of phenolic content in AHE.AHE also exhibited higher total antioxidant capacity,good reducing power and a significant scavenger of reactive oxygen species like DPPH radical,nitric oxide,hydrogen peroxide and deoxyribose.Furthermore there was a significant increase in the body weight and decrease in the blood glucose level on treatment with the AHE.AHE increased glucose uptake on isolated rat hemi-diaphragm compared to control group.Conclusions:AHE reduce blood glucose level in STZ-induced diabetic model.It does not show significant effect in normoglycemic study but showes significant effect in OGT.AHE has significant antioxidant activity,which may be attributed to high phenolic content.
基金Serum Institute of India, Pune, India and Indian Council for Medical Research (ICMR) New Delhi, India
文摘AIM: To investigate the cellular defects by analyzing the (Th1/Th2) cytokine levels in vaccine responders and non-responders. METHODS: Peripheral blood mononuclear cell (PBMC) from responders and non-responders were stimulated with or with out recombinant HBsAg or PHA. Broad spectrum of cytokines viz (Th1) IFN-γ, IL-2, TNF-α, IL-12 and (Th2) IL-10, IL-4 were measured after in vitro stimulation with recombinant HBsAg and were compared with respective antibody titers. RESULTS: A significant decrease (P = 0.001) in Th1 and Th2 cytokines namely, IL-2, INF-γ, TNF-α and IL-10in non-responders was observed. The level of IL-4 was not significant between the three groups. Furthermore, despite a strong Th1 and Th2 cytokine response, the level of IL-12 was elevated in high-responders compared to other groups (P = 0.001) and demonstrated a positive correlation with anti-HBs titers and Th1 cytokine response. CONCLUSION: Our findings suggest that unrespon-siveness to recombinant hepatitis B vaccines (rHB) is multifactorial, including specific failure of antigen presentation or the lack of both T helper Th1 and Th2 response.
文摘Abdominal tuberculosis is an increasingly common disease that poses diagnostic challenge,as the nonspecific features of the disease which may lead to diagnostic delays and development of complications.This condition is regarded as a great mimicker of other abdominal pathology.A high index of suspicion is an important factor in early diagnosis.Abdominal involvement mayoccur in the gastrointestinal tract,peritoneum,lymphnodes or solid viscera.Various investigative methods have been used to aid in the diagnosis of abdominal tuberculosis.Early diagnosis and initiation of antituberculous therapy and surgical treatment are essential to prevent morbidity and mortality.Most of the patients respond very well to standard antitubercular therapy and surgery is required only in a minority of cases.Imaging plays an important role in diagnosis of abdominal tuberculosis because early recognition of this condition is important.We reviewed our experience with the findings on various imaging modalities for diagnosis of this potentially treatable disease.
基金Supported by National Natural Science Foundation of China,No.30672408
文摘AIM:To evaluate the effect of hepatitis B virus (HBV) infection on liver metastasis of colorectal cancer.METHODS:A total of 1298 colorectal cancer patients were recruited from January 2001 to March 2005 in this study.Enzyme-linked immunosorbent assay was used to test serum HBV markers for colorectal cancer.Patients were divided into study (infection) group and control (non-infection) group.Clinical features of patients in two groups were compared.RESULTS:Liver metastasis was found in 319 out of the 1298 colorectal cancer patients.The incidence of liver metastasis was significantly lower in study group than in control group (14.2% vs 28.2%,P < 0.01).HBV infection significantly decreased the risk of liver metastasis [hazard ratio (HR):0.50,95% confidence interval (95% CI):0.38-0.66],but the incidence of extrahepatic metastasis was significantly higher in study group than in control group (31.9% vs 17.0%,P < 0.01).The HR was the lowest in chronic hepatitis B group (HR:0.29,95% CI:0.12-0.72).The number of liver metastatic lesions was significantly less in study group than in control group with a higher surgical resection rate.However,no significant difference was found in survival rate between the two groups (P=0.95).CONCLUSION:HBV infection decreases the risk of liver metastasis in patients with colorectal cancer and elevates the surgical resection rate of liver metastatic lesions.
文摘Harmine,a beta-carboline alkaloid,is widely distributed in the plants,marine creatures,insects, mammalians as well as in human tissues and body fluids.Harmine was originally isolated from seeds of Peganum harmal in 1847 having a core indole structure and a pyridine ring.Harmine has various types of pharmacological activities such as antimicrobial,antifungal,antitumor,cytotoxic, antiplasmodial,antioxidaant,antimutagenic,antigenotoxic and hallucinogenic properties.It acts on gamma-aminobutyric acid type A and monoamine oxidase A or B receptor,enhances insulin sensitivity and also produces vasorelaxant effect.Harmine prevents bone loss by suppressing osteoclastogenesis.The current review gives an overview on pharmacological activity and analytical techniques of harmine,which may be useful for researcheres to explore the hidden potential of harmine and and will also help in developing new drugs for the treatment of various diseases.
文摘Although beneficial in acute and chronic pain management, the use of local anaesthetics is limited by itsduration of action and the dose dependent adverse effects on the cardiac and central nervous system. Adjuvants or additives are often used with local anaesthetics for its synergistic effect by prolonging the duration of sensory-motor block and limiting the cumulative dose requirement of local anaesthetics. The armamentarium of local anesthetic adjuvants have evolved over time from classical opioids to a wide array of drugs spanning several groups and varying mechanisms of action. A large array of opioids ranging from morphine, fentanyl and sufentanyl to hydromorphone, buprenorphine and tramadol has been used with varying success. However, their use has been limited by their adverse effect like respiratory depression, nausea, vomiting and pruritus, especially with its neuraxial use. Epinephrine potentiates the local anesthetics by its antinociceptive properties mediated by alpha-2 adrenoreceptor activation along with its vasoconstrictive properties limiting the systemic absorption of local anesthetics. Alpha 2 adrenoreceptor antagonists like clonidine and dexmedetomidine are one of the most widely used class of local anesthetic adjuvants. Other drugs like steroids(dexamethasone), anti-inflammatory agents(parecoxib and lornoxicam), midazolam, ketamine, magnesium sulfate and neostigmine have also been used with mixed success. The concern regarding the safety profile of these adjuvants is due to its potential neurotoxicity and neurological complications which necessitate further research in this direction. Current research is directed towards a search for agents and techniques which would prolong local anaesthetic action without its deleterious effects. This includes novel approaches like use of charged molecules to produce local anaesthetic action(tonicaine and n butyl tetracaine), new age delivery mechanisms for prolonged bioavailability(liposomal, microspheres and cyclodextrin systems) and further studies with
基金Council of Science and Technology, Governmentof Uttar Pradesh, India, No. CST/SERPD/D-3402The financialassistance from Indian Council of Medical Research (ICMR),New Delhi, No. 80/512/2004-ECD-I
文摘AIM: To investigate -765G > C COX-2 polymorphism and H pylori infection in patients with gastric adenocarcinoma, peptic ulcer disease (PUD) and non- ulcer dyspepsia (NUD). METHODS: We enrolled 348 adult patients (62 gastric adenocarcinoma, 45 PUD and 241 NUD) undergoing upper gastrointestinal endoscopy at two referral centers between September, 2002 and May, 2007. H pylori infection was diagnosed when any of the four tests (RUT, culture, histopathology and PCR) were positive. Genotyping for -765G > C polymorphism of COX-2 was performed by PCR-RFLP analysis. RESULTS: Frequency of C carrier had significantassociation with gastric adenocarcinoma as compared to NUD [77.4% vs 29%, P < 0.001, odds ratio (OR) 8.20; 95% confidence interval (95% CI), 4.08-16.47] and PUD (77.4% vs 31.1%, P < 0.001; OR 8.04; 95% CI, 3.25-19.90). Risk of gastric adenocarcinoma was significantly higher in patients having C carrier with (OR 7.83; 95% CI 3.09-19.85) and without H pylori infection (OR 7.06; 95% CI, 2.61-19.09). Patients with C carrier and H pylori infection had significant risk for the development of PUD (P < 0.001; OR 5.65; 95% CI, 2.07-15.34). CONCLUSION: -765G > C COX-2 polymorphism with or without H pylori could be a marker for genetic susceptibility to gastric adenocarcinoma. COX-2 polymorphism in presence of H pylori infection might be useful in predicting the risk of PUD.
文摘Chronic haemorrhagic radiation proctitis(CHRP) is a difficult problem faced by the patients following radiation for pelvic malignancy. There is no standardtreatment for this condition, but many methods of treatment are available. The aim of this study was to review the literature to see whether there is an improvement in the available evidence in comparison with previously published systematic reviews in treating patients with CHRP. The Pub Med/Medline database and Google Scholar search was selectively searched. Studies, which treated patients with rectal bleeding due to chronic radiation proctitis or CHRP, were included. Seventy studies were finally selected out of which 14 were randomized controlled clinical trials. Though these studies could not be compared, it could be seen that there was an improvement in the methodology of the studies. There was an objective assessment of symptoms, signs and an objective assessment of outcomes. But, still, there were only a few studies that looked into the quality of life following treatment of CHRP. To increase recruitment to trials, a national registry of cases with established late radiation toxicity would facilitate the further improvement of such studies. Some of the conclusions that could be reached based on the available evidence are 4% formalin should be the first line treatment for patients with CHRP. Formalin and argon plasma coagulation(APC) are equally effective, but formalin is better for severe disease. Refractory patients, not responding to formalin or APC, need to be referred for hyperbaric oxygen therapy or surgery. Radio-frequency ablation is a promising modality that needs to be studied further in randomized trials.
文摘Helicobacter pylori(H. pylori) infection is highly prevalent in human,affecting nearly half of the world's population; however,infection remains asymptomatic in majority of population. During its co-existence with humans,H. pylori has evolved various strategies to maintain a mild gastritis and limit the immune response of host. On the other side,presence of H.pylori is also associated with increased risk for the development of various gastric pathologies including gastric cancer(GC). A complex combination of host genetics,environmental agents,and bacterial virulence factors are considered to determine the susceptibility as well as the severity of outcome in a subset of individuals. GC is one of the most common cancers and considered as the third most common cause of cancer related death worldwide. Many studies had proved H. pylori as an important risk factor in the development of non-cardia GC. Although both H. pylori infection and GC are showing decreasing trends in the developed world,they still remain a major threat to human population in the developing countries. The current review attempts to highlight recent progress in the field of research on H. pylori induced GC and aims to provide brief insight into H. pylori pathogenesis,the role of major virulence factors of H. pylori that modulates the host environment and transform the normal gastric epithelium to neoplastic one. This review also emphasizes on the mechanistic understanding of how colonization and various virulence attributes of H. pylori as well as the host innate and adaptive immune responses modulate the diverse signaling pathways that leads to different disease outcomes including GC.
文摘Herbal medicines, mainly of plant source, are invaluable source for the discovery of new therapeutic agents for all sorts of human ailments. The complex pathogenesis of stroke and multifactorial effect of herbal medicine and their active constituents may suggest the promising future of natural medicine for stroke treatment. Anti-oxidant, anti-inflammatory, anti-apoptotic, neuroprotective and vascular protective effect of herbal medicines are believed to be efficacious in stroke treatment. Herbs typically have fewer reported side effects than allopathic medicine, and may be safer to use over longer period of time. Herbal medicines are believed to be more effective for the longstanding health complaints, such as stroke. Several medicinal plants and their active constituents show the promising results in laboratory research. However failure in transformation of laboratory animal research to the clinical trials has created huge challenge for the use of herbal medicine in stroke. Until and unless scientifically comprehensive evidence of the efficacy and safety of herbal medicine in ischemic stroke patients is available, efforts should be made to continue implementing treatment strategies of proven effectiveness. More consideration should be paid to natural compounds that can have extensive therapeutic time windows, perfect pharmacological targets with few side effects. Herbal medicine has excellent prospective for the treatment of ischemic stroke, but a lot of effort should be invested to transform the success of animal research to human use.
基金supported by NIH Grants CA182872 and CA190291 to S.Anant.S.Anant is an Eminent Scientist of the Kansas Biosciences Authority
文摘Nature is a rich source of medicinal plants and their products that are useful for treatment of various diseases and disorders. Momordica charantia, commonly known as bitter melon or bitter gourd, is one of such plants known for its biological activities used in traditional system of medicines. This plant is cultivated in all over the world, including tropical areas of Asia, Amazon, east Africa, and the Caribbean and used as a vegetable as well as folk medicine. All parts of the plant, including the fruit, are commonly consumed and cooked with different vegetables, stir-fried, stuffed or used in small quantities in soups or beans to give a slightly bitter flavor and taste. The plant is reported to possess anti-oxidant, anti-inflammatory, anti-cancer, anti-diabetic, anti-bacterial, anti-obesity, and immunomodulatory activities. The plant extract inhibits cancer cell growth by inducing apoptosis, cell cycle arrest, autophagy and inhibiting cancer stem cells. The plant is rich in bioactive chemical constituents like cucurbitane type triterpenoids, triterpene glycosides, phenolic acids, flavonoids, essential oils, saponins, fatty acids, and proteins. Some of the isolated compounds （Kuguacin J, Karaviloside XI, Kuguaglycoside C, Momordicoside Q-U, Charantin, a-eleostearic acid） and proteins （a-Momorcharin, RNase MC2, MAP30） possess potent biological activity. In the present review, we are summarizing the anti-oxidant, anti-inflammatory, and anti-cancer activities of Momordica charantia along with a short account of important chemical constituents, providing a basis for establishing detail biological activities of the plant and developing novel drug molecules based on the active chemical constituents.
文摘Vasopressors are routinely used to counteract hypotension after neuraxial anesthesia in Obstetrics. The understanding of the mechanism of hypotension and the choice of vasopressor has evolved over the years to a point where phenylephrine has become the preferred vasopressor. Due to the absence of definitive evidence showing absolute clinical benefit of one over the other, especially in emergency and high-risk Cesarean sections, our choice of phenylephrine over the other vasopressors like mephentermine, metaraminol, and ephedrine is guided by indirect evidence on fetalacid-base status. This review article evaluates the present day evidence on the various vasopressors used in obstetric anesthesia today.
基金financially supported by University Grants Commission,New Delhi
文摘Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly esteemed source of medicine therefore,they have become a growing part of modern,high-tech medicine.In view of the above aspects the present review provides profiles of plants(65 species) with hypoglycaemic properties,available through literature source from various database with proper categorization according to the parts used,mode of reduction in blood glucose(insulinomimetic or insulin secretagugues activity) and active phyloconsliluents having insulin mimetics activity.From the review it was suggested that,plant showing hypoglycemic potential mainly belongs to the family Leguminoseae,Lamiaceae,Liliaceae,Cucurbitaceae, Asteraceae,Moraceae,Rosaceae and Araliaceae.The most active plants are Allium sativum. Gymnema sylvestre,Citrullus colocynthis,Trigonella foenum greacum,Momordica charantia and Ficuts bengalensis.The review describes some new bioactive drugs and isolated compounds from plants such as roseoside,epigallocatechin gallate,beta-pyrazol-1-ylalanine,cinchonain Ib,leucocyandin 3-O-beta-d-galactosyl cellobioside,leucopelargonidin-3- O-alpha-L rhamuoside,glycyrrhetinic acid,dehydrotrametenolic acid,strictinin,isostrictinin,pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents.Thus,from the review majorly,the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols,flavonoida, terpenoids,coumarins and other constituents which show reduction in blood glucose levels.The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.
