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| 1 | Effect of obstructive sleep apnea on type 2 diabetes mellitus:A comprehensive literature review显示文摘Obstructive sleep apnea(OSA)is frequently associated with obesity and metabolic syndrome.Also frequently associated with metabolic syndrome is type 2 diabetes mellitus(T2DM).Therefore,it is common to find OSA and T2DM together in individuals with metabolic syndrome.Additionally,both OSA and T2DM have a common pathophysiological link with development of insulin resistance.Individuals with severe insulin resistance are likely to have inadequate glycemic control.Long standing poorly controlled T2DM is associated with debilitating microvascular complications such as retinopathy,nephropathy,neuropathy and macrovascular complications such as coronary artery and cerebrovascular disease.There is extensively published literature exploring the cause-effect relationship between OSA and T2DM.In this article we provide an in-depth review of the complex pathophysiological mechanisms linking OSA to T2DM.Specifically,this review focusses on the effect of OSA on the microvascular complications of T2DM such as retinopathy,nephropathy and neuropathy.Additionally,we review the current literature on the effect of continuous positive airway pressure use in individuals with T2DM and OSA. | Srikant Nannapaneni Kannan Ramar Salim Surani | 2013 | World Journal of Diabetes2013，4，6： | 24 |
| 2 | Biodegradation behavior of micro-arc oxidation coating on magnesium alloy-from a protein perspective显示文摘Protein exerts a critical influence on the degradation behavior of absorbable magnesium(Mg)-based implants.However,the interaction mechanism between protein and a micro-arc oxidation(MAO)coating on Mg alloys remains unclear.Hereby,a MAO coating was fabricated on AZ31 Mg alloy.And its degradation behavior in phosphate buffer saline(PBS)containing bovine serum albumin(BSA)was investigated and compared with that of the uncoated alloy.Surface morphologies and chemical compositions were studied using Field-emission scanning electron microscope(FE-SEM),Fourier transform infrared spectrophotometer(FT-IR)and X-ray diffraction(XRD).The degradation behavior of the bare Mg alloy and its MAO coating was studied through electrochemical and hydrogen evolution tests.Cytotoxicity assay was applied to evaluate the biocompatibility of Mg alloy substrate and MAO coating.Results indicated that the presence of BSA decreased the degradation rate of Mg alloy substrate because BSA(RCH(NH2)COO‾)molecules combined with Mg2+ions to form(RCH(NH2)COO)2Mg and thus inhibited the dissolution of Mg(OH)2 by impeding the attack of Cl‾ions.In the case of MAO coated Mg alloy,the adsorption of BSA on MAO coating and the formation of(RCH(NH2)COO)2Mg exhibited a synergistic effect and enhanced the corrosion resistance of the coated alloy significantly.Furthermore,cell bioactive assay suggested that the MAO coating had good viability for MG63 cells due to its high surface area. | Zhao-Qi Zhang Li Wang Mei-Qi Zeng Rong-Chang Zeng M.Bobby Kannan Cun-Guo Lin Yu-Feng Zheng | 2020 | Bioactive Materials2020，5，2： | 17 |
| 3 | Corrosion resistance of in-situ growth of nano-sized Mg(OH)2 on micro-arc oxidized magnesium alloy AZ31—Influence of EDTA显示文摘One of the major obstacles for the clinical use of biodegradable magnesium(Mg)-based materials is their high corrosion rate. Micro-arc oxidation(MAO) coatings on Mg alloys provide mild corrosion protection owing to their porous structure. Hence, in this study a dense Mg(OH)2 film was fabricated on MAO-coated Mg alloy AZ31 in an alkaline electrolyte containing ethylenediamine tetraacetic acid disodium(EDTA-2 Na) to reinforce the protection. Surface morphology, chemical composition and growth process of the MAO/Mg(OH)2 hybrid coating were examined using field-emission scanning electron microscopy, energy dispersive X-ray spectrometer, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectrophotometer. Corrosion resistance of the coatings was evaluated via potentiodynamic polarization curves and hydrogen evolution tests. Results manifested that the Mg(OH)2 coating possesses a porous nano-sized structure and completely seals the micro-pores and micro-cracks of the MAO coating.The intermetallic compound of AlMn phase in the substrate plays a key role in the growth of Mg(OH)2 film. The current density of Mg(OH)2-MAO composite coating decreases three orders of magnitude in comparison with that of bare substrate, indicating excellent corrosion resistance. The Mg(OH)2-MAO composite coating is beneficial to the formation of calcium phosphate corrosion products on the surface of Mg alloy AZ31, demonstrating a great promise for orthopaedic applications. | Chang-Yang Li Xiao-Li Fan Rong-Chang Zeng Lan-Yue Cui Shuo-Qi Li Fen Zhang Qing-Kun He M. Bobby Kannan Hong-Wei (George) Jiang Dong-Chu Chen Shao-Kang Guan | 2019 | Journal of Materials Science & Technology2019，35，6： | 16 |
| 4 | In vitro antioxidant activities of ethanol extract from Enhalus acoroides (L.F.) Royle显示文摘Objective:To search for new sources of safe and inexpensive antioxidants,the leaf,root and rhizome of Enhalus acoroides(E.acoroides) were screened for the first time for their antioxidant activities.Methods:Samples of leaf,root and rhizome from E.acoroides were tested for total phenolic content,proanthocyanidins and in vitro antioxidant activity in terms of total antioxidant assay,DPPH assay and FRAP assay.Results:The leaf sample was found to have high levels of phenolic(0.323±0.028 mg TAE/g) and proanthocyanidins(0.570 0±0.000 3 mg TAE/g) when compared to root and rhizome.The leaf samples exhibited higher total antioxidant activity (11.770±0.026 mg Ascorbic acid equivalent/g),higher percentage of DPPH radical scavenging activity(25.76±0.04) and higher reducing power(18.060±0.073) in terms of mg GAE/g.In addition, there was a significant correlation between total phenolic content and total antioxidant activity (R^2=0.923),DPPH assay(R^2=0.509).FRAP assay(R^2=0.994).Similarly,significant correlation was found between the proanthocyanidin and total antioxidant activity(R^2=0.977),DPPH assay (R^2=0.464) and the FRAP assay(R^2=0.998).Conclusions:These results suggested that E.acoroides have strong antioxidant potential.Further study is necessary for isolation and characterization of the active antioxidant agents,which can be used to treat various oxidative stress-related diseases. | Rengasamy Ragupathi Raja Kannan Rajasekaran Arumugam Perumal Anantharaman | 2010 | Asian Pacific Journal of Tropical Medicine2010，3，11： | 15 |
| 5 | Corrosion resistance of nanostructured magnesium hydroxide coating on magnesium alloy AZ31: influence of EDTA显示文摘A hexagonal nanosheet Mg(OH)2 coating was prepared through a one-step hydrothermal method using LiOH solution as mineralizer and then modified by ethylenediaminetetraacetic acid(EDTA) to minimize the rapid corrosion of AZ31 Mg alloy.The performance of the coating was evaluated using electrochemical technique,hydrogen evolution measurements, nanoscratch test,Fourier-transform infrared spectroscopy(FTIR), X-ray diffraction(XRD) patterns and field-emission scanning electron microscopy(FESEM).The results suggested that the corrosion rate of bare AZ31 Mg alloys was significantly reduced by one and two orders of magnitude through the protection from Mg(OH)2 coating and modification with EDTA(i.e., EDTA-Mg(OH)2 coating), respectively.FESEM micrographs indicated that the modification in EDTA elicits to the formation of an EDTA-Mg(OH)2 composite with a thickness as twice as that of as-prepared Mg(OH)2 coating.Nanoscratch tests revealed strong adhesion between the composite or Mg(OH)2 coating and the substrate.The study of formation and corrosion mechanisms of the coatings manifested that Mg(OH)2 was first formed near the intermetallic compound AlMn particles and gradually covered the entire surface, wherein the AlMn particles played an important role in the coating growth process.And it also proved that EDTA accelerated the formation of Mg(OH)2. | Xiao-Li Fan Yuan-Fang Huo Chang-Yang Li M.Bobby Kannan Xiao-Bo Chen Shao-Kang Guan Rong-Chang Zeng Quan-Li Ma | 2019 | Rare Metals2019，38，6： | 11 |
| 6 | Mercury remediation potential of a mercury resistant strain Sphingopyxis sp.SE2 isolated from contaminated soil显示文摘A mercury resistant bacterial strain SE2 was isolated from contaminated soil.The 16 s rRNA gene sequencing confirms the strain as Sphingopyxis belongs to the Sphingomonadaceae family of the α-Proteobacteria group.The isolate showed high resistance to mercury with estimated concentrations of Hg that caused 50%reduction in growth(EC_(50)) of 5.97 and 6.22 mg/L and minimum inhibitory concentrations(MICs) of 32.19 and 34.95 mg/L in minimal and rich media,respectively.The qualitative detection of volatilized mercury and the presence of mercuric reductase enzyme proved that the strain SE2 can potentially remediate mercury.ICP-QQQ-MS analysis of the remaining mercury in experimental broths indicated that a maximum of 44%mercury was volatilized within 6 hr by live SE2 culture.Furthermore a small quantity(23%) of mercury was accumulated in live cell pellets.While no volatilization was caused by dead cells,sorption of mercury was confirmed.The mercuric reductase gene merA was amplified and sequenced.Homology was observed among the amino acid sequences of mercuric reductase enzyme of different organisms from a-Proteobacteria and ascomycota groups, | Khandaker Rayhan Mahbub Kannan Krishnan Ravi Naidu Mallavarapu Megharaj | 2017 | Journal of Environmental Sciences2017，29，1： | 10 |
| 7 | Comparative Study of the Large Eddy Simulations with the Lattice Boltzmann Method Using the Wall-Adapting Local Eddy-Viscosity and Vreman Subgrid Scale Models显示文摘The wall-adapting local eddy-viscosity(WALE)and Vreman subgrid scale models for large eddy simulations are compared within the framework of a generalised lattice Boltzmann method.Fully developed turbulent flows near a flat wall are simulated with the two models for the shear(or friction)Reynolds number of 183.6.Compared to the direct numerical simulation(DNS),damped eddy viscosity in the vicinity of the wall and a correct velocity profile in the transitional region are achieved by both the models without dynamic procedures.The turbulent statistics,including,e.g.,root-mean-square velocity fluctuations,also agree well with the DNS results.The comparison also shows that the WALE model predicts excellent damped eddy viscosity near the wall. | 刘明 陈效鹏 Kannan N.Premnath | 2012 | Chinese Physics Letters2012，29，10： | 9 |
| 8 | Renal sympathetic nervous system and the effects of denervation on renal arteries显示文摘Resistant hypertension is associated with chronic activation of the sympathetic nervous system resulting in various comorbidities. The prevalence of resistant hypertension is often under estimated due to various reasons. Activation of sympathetic nervous system at the renal-as well as systemic-level contributes to the increased level of catecholamines and resulting increase in the blood pressure. This increased activity was demonstrated by increased muscle sympathetic nerve activity and renal and total body noradrenaline spillover. Apart from the hypertension, it is hypothesized to be associated with insulin resistance, congestive heart failure and obstructive sleep apnea. Renal denervation is a novel procedure where the sympathetic afferent and efferent activity is reduced by various techniques and has been used successfully to treat drug-resistant hypertension improvement of various metabolic derangements.Renal denervation has the unique advantage of offering the denervation at the renal level, thus mitigating the systemic side effects. Renal denervation can be done by various techniques including radiofrequency ablation, ultrasound guided ablation and chemical ablation. Various trials evaluated the role of renal denervation in the management of resistant hypertension and have found promising results. More studies are underway to evaluate the role of renal denervation in patients presenting with resistant hypertension in different scenarios. Appropriate patient selection might be the key in determining the effectiveness of the procedure. | Arun Kannan Raul Ivan Medina Nagapradeep Nagajothi Saravanan Balamuthusamy | 2014 | World Journal of Cardiology2014，6，8： | 8 |
| 9 | Neuroendocrine carcinoma of the ampulla of Vater:a clinicopathologic evaluation显示文摘BACKGROUND:Only 105 cases of neuroendocrine tumor(NET)of the ampulla of Vater have been described, mostly as single case reports.The incidence of NET is rising.The changes in incidence may result from changes in detection.This study was to determine the relative incidence and clinicopathological characteristics of high- grade neuroendocrine carcinoma(small cell carcinoma and large cell carcinoma)of the ampulla of Vater at a single institution. METHODS:Sections from paraffin blocks of tumors of the ampulla of Vater taken from 45 patients who underwent Whipple's procedure and 6 patients who underwent palliative bypass between September 2003 and January 2007 were subjected to immunohistochemical analysis.The clinical and pathological data from 5 patients diagnosed with NET of the ampulla of Vater were analyzed. RESULTS:The patients were 3 men and 2 women,ranging in age from 39 to 47 years(mean 44 years).Operative procedures included Whipple's procedure in 4 patients and palliative bypass in 1 patient.Histopathological examination revealed large-cell neuroendocrine carcinoma in 2 patients,small cell carcinoma in 2,and carcinoid in 1.Three patients with high-grade neuroendocrine carcinoma who had undergone Whipple's procedure died at postoperatively 7,11,and 13 months.The patient who had undergone palliative triple bypass died 3 months after surgery.CONCLUSIONS:The relative incidence of high-grade neuroendocrine carcinomas of the ampulla of Vater is higher than that generally expected.The tumors behave aggressively and have a dismal prognosis despite aggressive treatment. | Eswaran Selvakumar Shanmugasundaram Rajendran Tirupporur Govindaswamy Balachandar Devy Gounder Kannan Satyanesan Jeswanth Palaniappan Ravichandran Rajagopal Surendran | 2008 | Hepatobiliary & Pancreatic Diseases International2008，7，4： | 7 |
| 10 | Sodium iodate induced retinal degeneration: new insights from an old model显示文摘Studies on the selective retinal degeneration induced by sodium iodate(Na IO3)date back to 1941;Sorsby(1941)described the effect of intravenously injected Na IO3solution on the rabbit retina.Since then,Na IO3-induced retinal degeneration has been described in different mammalian species including sheep,rabbit,rat and mouse with varying doses and routes of administration.At the present time,the murine Na IO3model is the most widely used because it results in reproducible,patchy retinal degeneration(Figure 1)and can be studied in a wide variety of wild type and genetic knockout strains. | Ram Kannan David R.Hinton | 2014 | Neural Regeneration Research2014，9，23： | 7 |
| 11 | Antibacterial potential of three seagrasses against human pathogens显示文摘Objective:To evaluate the antibacterial activity of Halophila stipulacea(H.stipulacea), Cymodocea serrulata(C.serrulata) and Halodule pinifolia(H.pinifolia) against seven human bacterial pathogens.Methods:The antibacterial activities of the extracts on the various test organisms using disc diffusion method and Minimum Inhibitory Concentraction(MIC).Results: Methanol and chloroform extracts of all the three seagrasses were active against all the tested pathogens,whereas the hexane extract of seagrasses was not active against Staphylococcus aureus (S.aureus).Antibacterial activity of three seagrass screened,was in the order of H.pinifolia > H.stipulacea.> C.serrulata.Conclusions:This antibacterial studies can further investigated on seagrasses for purification of bioactive substance and its possible utility in disease control. | Rengasamy Ragupathi Raja Kannan Rajasekaran Arumugam Perumal Anantharaman | 2010 | Asian Pacific Journal of Tropical Medicine2010，3，11： | 7 |
| 12 | Kinetics of phenol and m-cresol biodegradation by an indigenous mixed microbial culture isolated from a sewage treatment plant显示文摘An acclimatized mixed microbial culture,predominantly Pseudomonas sp.,was enriched from a sewage treatment plant,and its potential to simultaneously degrade mixtures of phenol and m-cresol was investigated during its growth in batch shake flasks.A 22 full factorial design with the two substrates at two different levels and different initial concentration ranges(low and high),was employed to carry out the biodegradation experiments.The substrates phenol and m-cresol were completely utilized within 21 h when present at low concentrations of 100 mg/L for each,and at high concentration of 600 mg/L for each,a maximum time of 187 h was observed for their removal.The biodegradation results also showed that the presence of phenol in low concentration range(100–300 mg/L) did not inhibit m-cresol biodegradation.Whereas the presence of m-cresol inhibited phenol biodegradation by the culture.Moreover, irrespective of the concentrations used,phenol was degraded preferentially and earlier than m-cresol.A sum kinetics model was used to describe the variation in the substrate specific degradation rates,which gave a high coeffcient of determination value(R2>0.98)at the low concentration range of the substrates.From the estimated interaction parameter values obtained from this model,the inhibitory effect of phenol on m-cresol degradation by the culture was found to be more pronounced compared to that of m-cresol on phenol.This study showed a good potential of the indigenous mixed culture in degrading mixed substrate of phenolics. | Pichiah Saravanan Kannan Pakshirajan Prabirkumar Saha | 2008 | Journal of Environmental Sciences2008，20，12： | 7 |
| 13 | A Neuro-genetic Based Short-term Forecasting Framework for Network Intrusion Prediction System显示文摘Information systems are one of the most rapidly changing and vulnerable systems, where security is a major issue. The number of security-breaking attempts originating inside organizations is increasing steadily. Attacks made in this way, usually done by 'authorized' users of the system, cannot be immediately traced. Because the idea of filtering the traffic at the entrance door, by using firewalls and the like, is not completely successful, the use of intrusion detection systems should be considered to increase the defense capacity of an information system. An intrusion detection system (IDS) is usually working in a dynamically changing environment, which forces continuous tuning of the intrusion detection model, in order to maintain sufficient performance. The manual tuning process required by current IDS depends on the system operators in working out the tuning solution and in integrating it into the detection model. Furthermore, an extensive effort is required to tackle the newly evolving attacks and a deep study is necessary to categorize it into the respective classes. To reduce this dependence, an automatically evolving anomaly IDS using neuro-genetic algorithm is presented. The proposed system automatically tunes the detection model on the fly according to the feedback provided by the system operator when false predictions are encountered. The system has been evaluated using the Knowledge Discovery in Databases Conference (KDD 2009) intrusion detection dataset. Genetic paradigm is employed to choose the predominant features, which reveal the occurrence of intrusions. The neuro-genetic IDS (NGIDS) involves calculation of weightage value for each of the categorical attributes so that data of uniform representation can be processed by the neuro-genetic algorithm. In this system unauthorized invasion of a user are identified and newer types of attacks are sensed and classified respectively by the neuro-genetic algorithm. The experimental results obtained in this work show that the system achieves improvement in terms of misclassification cost when compared with conventional IDS. The results of the experiments show that this system can be deployed based on a real network or database environment for effective prediction of both normal attacks and new attacks. | Siva S. Sivatha Sindhu S. Geetha M. Marikannan A. Kannan | 2009 | International Journal of Automation and computing2009，6，4： | 7 |
| 14 | Glucose control in critical care显示文摘Glycemic control among critically-ill patients has been a topic of considerable attention for the past 15 years. An initial focus on the potentially deleterious effects of hyperglycemia led to a series of investigations regarding intensive insulin therapy strategies that targeted tight glycemic control. As knowledge accumulated, the pursuit of tight glycemic control among critically-ill patients came to be seen as counterproductive, and moderate glycemic control came to dominate as the standard practice in intensive care units. In recent years, there has been increased focus on the importance of hypoglycemic episodes, glycemic variability, and premorbid diabetic status as factors that contribute to outcomes among critically-ill patients. This review provides a survey of key studies on glucose control in critical care, and aims to deliver perspective regarding glycemic management among critically-ill patients. | Jeremy Clain Kannan Ramar Salim R Surani | 2015 | World Journal of Diabetes2015，6，9： | 7 |
| 15 | EXPERIMENTAL AND NUMERICAL ANALYSIS OF LAMINAR AND LOW TURBULENT FLOW DISTRIBUTIONS IN INLET DIVIDING HEADER OF SHELL AND TUBE HEAT EXCHANGER显示文摘Flow distribution headers play a major role in heat exchangers.The selection of header diameter,branch pipe diameter,branch pipe spacing etc.is based on the designer's experience and general guide lines.The proper selection of the header dimensions will yield uniform flow distribution in heat exchangers,which in turn will enhance the heat exchanger efficiency.In this work,the flow distribution in branch pipes and the pressure variation across the branch pipes in laminar and low turbulence region is studied with two models of the inlet dividing headers.When the numerical analysis has been applied,its inability to predict the no flow condition through the branch pipes is revealed.The results are presented in the form of flow rate ratio through branch pipes and nondimensional coefficients across branch pipes which are useful to apply the existing mathematical models for the present experimental setup. | KANNAN K. RUDRAMOORTHY R. | 2010 | Journal of Hydrodynamics2010，22，4： | 6 |
| 16 | Long-term outcome of gastric access loop in hepaticojejunostomy显示文摘BACKGROUND:The incidence of hepaticojejunostomy stricture is 4%-10% in experienced centres. Many access loops have been designed and used to facilitate endoscopic intervention for this complication of hepaticojejunostomy. In this study, we investigated the effectiveness and safety of gastric access loop. METHODS:A retrospective analysis was conducted on 13 patients who had undergone hepaticojejunostomy with gastric access loop between June 1999 and September 2003. Eleven patients were followed up for a mean period of 51 months (range 20-81 months). Two patients were lost to follow up. RESULTS:On follow-up, 8 patients had patent jejuno- gastrostomy (end to side anastomosis between Roux loop of jejunum and stomach) and hepaticojejunostomy. Three patients developed stricture of jejunogastrostomy at 41 months, 63 months and 81 months of follow-up. Among these 3 patients, one also had hepaticojejunostomy stricture. In the patient with hepaticojejunostomy stricture, dilatation of jejunogastrostomy stricture was attempted but failed. None of the patients had any evidence of bile gastritis/cholangitis. There was no procedure related morbidity/mortality. CONCLUSIONS:Further studies involving large numbers of patients are required before wide application of gastric access loop in hepaticojejunostomy though it is a safer option than percutaneous transhepatic manipulations or revision surgery. | Eswaran Selvakumar Shanmugasundaram Rajendran Tirupporur G. Balachandar Devy Gounder Kannan Satyanesan Jeswanth Palaniappan Ravichandran Rajagopal Surendran | 2008 | Hepatobiliary & Pancreatic Diseases International2008，7，2： | 6 |
| 17 | Dealloying corrosion of anodic and nanometric Mg41Nd5 in solid solution-treated Mg-3Nd-1Li-0.2Zn alloy显示文摘The microstructure and chemical compositions of the solid solution-treated Mg-3 Nd-1 Li-0.2 Zn alloy were characterized using optical microscope,scanning electron microscope(SEM),transmission electron microscope(TEM),electron probe micro-analyzer(EPMA)and X-ray photoelectron spectroscopy(XPS).The corrosion behaviour of the alloy was investigated via electrochemical polarization,electrochemical impedance spectroscopy(EIS),hydrogen evolution test and scanning Kelvin probe(SKP).The results showed that the microstructure of the as-extruded Mg-3 Nd-1 Li-0.2 Zn alloy containedα-Mg matrix and nanometric second phase Mg_(41)Nd_(5).The grain size of the alloy increased significantly with the increase in the heat-treatment duration,whereas the volume fraction of the second phase decreased after the solid solution treatment.The surface film was composed of oxides(Nd_(2)O_(3),Mg O,Li_(2)O and Zn O)and carbonates(Mg CO3 and Li_(2)CO3),in addition to Nd.The as-extruded alloy exhibited the best corrosion resistance after an initial soaking of 10 min,whereas the alloy with 4 h-solution-treatment possessed the lowest corrosion rate after a longer immersion(1 h).This can be attributed to the formation of Nd-containing oxide film on the alloys and a dense corrosion product layer.The dealloying corrosion of the second phase was related to the anodic Mg_(41)Nd_(5)with a more negative Volta potential relative toα-Mg phase.The preferential corrosion of Mg_(41)Nd_(5)is proven by in-situ observation and SEM.The solid solution treatment of Mg-3 Nd-1 Li-0.2 Zn alloy led to a shift in corrosion type from pitting corrosion to uniform corrosion under long-term exposure. | Gui-Jia Gao Mei-Qi Zeng En-Liang Zhang Rong-Chang Zeng Lan-Yue Cui Dao-kui Xu Feng-Qin Wang M.Bobby Kannan | 2021 | Journal of Materials Science & Technology2021，，24： | 6 |
| 18 | Cynodon dactylon andSida acuta extracts impact on the function of the cardiovascular system in zebrafish embryos显示文摘The aim of the present study was to screen cardioactive herbs from Western Ghats of India.The heart beat rate (HBR) and blood flow during systole and diastole were tested in zebrafish embryos.We found that Cynodon dactylon (C.dactylon) induced increases in the HBR in zebrafish embryos with a HBR of (3.968±0.344) beats/s,which was significantly higher than that caused by betamethosone [(3.770±0.344) beats/s].The EC 50 value of C.dactylon was 3.738 μg/mL.The methanolic extract of Sida acuta (S.acuta) led to decreases in the HBR in zebrafish embryos [(1.877±0.079) beats/s],which was greater than that caused by nebivolol (positive control).The EC 50 value of Sida acuta was 1.195 μg/mL.The untreated embryos had a HBR of (2.685±0.160) beats/s at 3 d post fertilization (dpf).The velocities of blood flow during the cardiac cycle were (2,291.667±72.169) μm/s for the control,(4,250±125.000) μm/s for C.dactylon and (1,083.333±72.169) μm/s for S.acuta.The LC 50 values were 32.6 μg/mL for C.dactylon and 20.9 μg/mL for S.acuta.In addition,the extracts exhibited no chemical genetic effects in the drug dosage range tested.In conclusion,we developed an assay that can measure changes in cardiac function in response to herbal small molecules and determine the cardiogenic effects by microvideography. | Rajaretinam Rajesh Kannan Samuel Gnana Prakash Vincent | 2012 | The Journal of Biomedical Research2012，26，2： | 5 |
| 19 | R-spondin-2 is a Wnt agonist that regulates osteoblast activity and bone mass显示文摘The R-spondin family of proteins are Wnt agonists, and the complete embryonic disruption of Rspo2 results in skeletal developmental defects that recapitulate the phenotype observed with Lrp5/6 deficiency. Previous work has shown that R-spondin-2(Rspo2, RSPO2) is both highly expressed in Wnt-stimulated pre-osteoblasts and its overexpression induces osteoblast differentiation in the same cells, supporting its putative role as a positive autocrine regulator of osteoblastogenesis. However, the role of Rspo2 in regulating osteoblastogenesis and bone formation in postnatal bone has not been explored. Here we show that limb-bud progenitor cells from Rspo2 knockout mice undergo reduced mineralization during osteoblastogenesis in vitro and have a corresponding alteration in their osteogenic gene expression profile. We also generated the first Rspo2 conditional knockout(Rspo2 floxed) mouse and disrupted Rspo2 expression in osteoblast-lineage cells by crossing to the Osteocalcin-Cre mouse line(OcnCre + Rspo2 ^(f/f)). Ocn-Cre + Rspo2 f/fmale and female mice at 1, 3, and 6 months were examined. Ocn-Cre + Rspo2 f/fmice are decreased in overall body size compared to their control littermates and have decreased bone mass. Histomorphometric analysis of1-month-old mice revealed a similar number of osteoblasts and mineralizing surface per bone surface with a simultaneous decrease in mineral apposition and bone formation rates. Consistent with this observation, serum osteocalcin in 3-month-old Ocn-Cre +Rspo2 f/fwas reduced, and bone marrow-mesenchymal stem cells from Ocn-Cre + Rspo2 f/fmice undergo less mineralization in vitro.Finally, gene expression analysis and immunohistochemistry of mature bone shows reduced beta-catenin signaling in Ocn-Cre +Rspo2 f/f. Overall, RSPO2 reduces osteoblastogenesis and mineralization, leading to reduced bone mass. | M.Noelle Knight Kannan Karuppaiah Michele Lowe Sarthak Mohanty Robert L.Zondervan Sheila Bell Jaimo Ahn Kurt D.Hankenson | 2018 | Bone Research2018，6，3： | 5 |
| 20 | Endoplasmic reticulum-mitochondrial crosstalk:a novel role for the mitochondrial peptide humanin显示文摘In this review,the interactive mechanisms of mitochondria with the endoplasmic reticulum(ER) are discussed with emphasis on the potential protective role of the mitochondria derived peptide humanin(HN) in ER stress.The ER and mitochondria are dynamic organelles capable of modifying their structure and function in response to changing environmental conditions.The ER and mitochondria join together at multiple sites and form mitochondria-ER associated membranes that participate in signal transduction pathways that are under active investigation.Our laboratory previously showed that HN protects cells from oxidative stress induced cell death and more recently,described the beneficial role of HN on ER stress-induced apoptosis in retinal pigment epithelium cells and the involvement of ER-mitochondrial cross-talk in cellular protection.The protection was achieved,in part,by the restoration of mitochondrial glutathione that was depleted by ER stress.Thus,HN may be a promising candidate for therapy for diseases that involve both oxidative and ER stress.Developing novel approaches for retinal delivery of HN,its analogues as well as small molecular weight ER stress inhibitors would prove to be a valuable approach in the treatment of age-related macular degeneration. | Parameswaran G.Sreekumar David R.Hinton Ram Kannan | 2017 | Neural Regeneration Research2017，12，1： | 5 |
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