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| 1 | Analysis of isoquinoline alkaloids from Mahonia leschenaultia and Mahonia napaulensis roots using UHPLC-Orbitrap-MSn and UHPLC-QqQ LIT-MS/MS显示文摘Mahonia leschenaultia(ML) and Mahonia napaulensis(MN) are less known and unexplored medicinal plants of the family Berberidaceae. They are used by the Todas of Nilgiris in their religious and medical practices but chemically less identified. Hence, we decided to do extensive phytochemical analysis to explore the potential of these plant extracts. An ultrahigh performance electrospray tandem mass spectrometry(UHPLC–ESI–MS/MS)method was successfully developed for qualitative analysis of the bioactive components in Mahonia species using Orbitrap Velos Pro mass spectrometer. Sixteen compounds were identified by comparison of their retention times and mass spectra(MS) with authentic standards and reported literature. Multi-stage mass spectra(MS^(2–8)) for the identification of protoberberine and aporphine alkaloids showed the sequential expulsion of all the substituents attached with their basic skeleton followed by CO loss. Eight of the identified compounds(berberine, jatrorrhizine, palmatine, magnoflorine, isocorydine, glaucine, tetrahydropalmatine and tetrahydroberberine) were simultaneously determined by another UHPLC–ESI–MS/MS method under the multiple reactions monitoring(MRM) mode quantitatively using triple quadrupole linear ion trap mass spectrometer. The analytical method was validated for 8 bioactive compounds with overall recovery in the range98.5%–103.6%(RSD≤2.2%), precise(RSD≤2.07%) and linear(r≥0.9995) over the concentration range of 0.5–1000 ng/mL and successfully applied in ML and MN roots, which suggests the suitability of the proposed approach for the routine analysis of Mahonia species and their quality control. | Awantika Singh Vikas Bajpai Sunil Kumar Ajay Kumar Singh Rawat Brijesh Kumar | 2017 | Journal of Pharmaceutical Analysis2017，7，2： | 9 |
| 2 | Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS显示文摘Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P.niruri. | Sunil Kumar Awantika Singh Brijesh Kumar | 2017 | Journal of Pharmaceutical Analysis2017，7，4： | 9 |
| 3 | Structural characterization of monoterpene indole alkaloids in ethanolic extracts of Rauwolfia species by liquid chromatography with quadrupole time-of-flight mass spectrometry显示文摘Rauwolfia species(Apocynaceae) are medicinal plants well known worldwide due to its potent bioactive monoterpene indole alkaloids(MIAs) such as reserpine,ajmalicine,ajmaline,serpentine and yohimbine.Reserpine,ajmalicine and ajmaline are powerful antihypertensive,tranquilizing agents used in hypertension.Yohimbine is an aphrodisiac used in dietary supplements.As there is no report on the comparative and comprehensive phytochemical investigation of the roots of Rauwolfia species,we have developed an efficient and reliable liquid chromatography-tandem mass spectrometry(LC–MS/MS) method for ethanolic root extract of Rauwolfia species to elucidate the fragmentation pathways for dereplication of bioactive MIAs using highperformance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry(HPLC–ESI–QTOF–MS/MS) in positive ion mode.We identified and established diagnostic fragment ions and fragmentation pathways using reserpine,ajmalicine,ajmaline,serpentine and yohimbine.The MS/MS spectra of reserpine,ajmalicine,and ajmaline showed C-ring-cleavage whereas E-ring cleavage was observed in serpentine via Retro Diels Alder(RDA).A total of 47 bioactive MIAs were identified and characterized on the basis of their molecular formula,exact mass measurements and MS/MS analysis.Reserpine,ajmalicine,ajmaline,serpentine and yohimbine were unambiguously identified by comparison with their authentic standards and other 42 MIAs were tentatively identified and characterized from the roots of Rauwolfia hookeri,Rauwolfia micrantha,Rauwolfia serpentina,Rauwolfia verticillata,Rauwolfia tetraphylla and Rauwolfia vomitoria.Application of LC–MS followed by principal component analysis(PCA) has been successfully used to discriminate among six Rauwolfia species. | Sunil Kumar Awantika Singh Vikas Bajpai Mukesh Srivastava Bhim Pratap Singh Brijesh Kumar | 2016 | Journal of Pharmaceutical Analysis2016，6，6： | 7 |
| 4 | Coagonist of glucagon-like peptide-1 and glucagon receptors ameliorates kidney injury in murine models of obesity and diabetes mellitus显示文摘AIM To investigate the role of glucagon-like peptide-1(GLP-1)/glucagon receptors coagonist on renal dysfunction associated with diabetes and obesity. METHODS Chronic high-fat diet fed C57 BL/6 J mice, streptozotocintreated high-fat diet fed C57 BL/6 J mice and diabeticC57 BLKS/J db/db mice were used as models of diabetes-induced renal dysfunction. The streptozotocintreated high-fat diet fed mice and db/db mice were treated with the GLP-1 and glucagon receptors coagonist(Aib2 C24 Chimera2, 150 μg/kg, sc) for twelve weeks, while in chronic high-fat diet fed mice, coagonist(Aib2 C24 Chimera2, 150 μg/kg, sc) treatment was continued for forty weeks. Kidney function, histology, fibrosis, inflammation, and plasma biochemistry were assessed at the end of the treatment. RESULTS Coagonist treatment decreased body weight, plasma lipids, insulin resistance, creatinine, blood urea nitrogen, urinary albumin excretion rate and renal lipids. In kidney, expression of lipogenic genes(SREBP-1 C, FAS, and SCD-1) was decreased, and expression of genes involved in β-oxidation(CPT-1 and PPAR-α) was increased due to coagonist treatment. In plasma, coagonist treatment increased adiponectin and FGF21 and decreased IL-6 and TNF-?. Coagonist treatment reduced expression of inflammatory(TNF-α, MCP-1, and MMP-9) and pro-fibrotic(TGF-β, COL1 A1, and α-SMA) genes and also improved histological derangement in renal tissue.CONCLUSION Coagonist of GLP-1 and glucagon receptors alleviated diabetes and obesity-induced renal dysfunction by reducing glucose intolerance, obesity, and hyperlipidemia. | Vishal J Patel Amit A Joharapurkar Samadhan G Kshirsagar Brijesh K Sutariya Maulik S Patel Hiren M Patel Dheerendra K Pandey Rajesh H Bahekar Mukul R Jain | 2018 | World Journal of Diabetes2018，9，6： | 5 |
| 5 | Particle manipulation beyond the diffraction limit using structured super-oscillating light beams显示文摘The diffraction-limited resolution of light focused by a lens was derived in 1873 by Ernst Abbe.Later in 1952,a method to reach sub-diffraction light spots was proposed by modulating the wavefront of the focused beam.In a related development,super-oscillating functions,that is,band-limited functions that locally oscillate faster than their highest Fourier component,were introduced and experimentally applied for super-resolution microscopy.Up till now,only simple Gaussian-like sub-diffraction spots were used.Here we show that the amplitude and phase profile of these sub-diffraction spots can be arbitrarily controlled.In particular,we utilize Hermite–Gauss,Laguerre–Gauss and Airy functions to structure super-oscillating beams with subdiffraction lobes.These structured beams are then used for high-resolution trapping and manipulation of nanometer-sized particles.The trapping potential provides unprecedented localization accuracy and stiffness,significantly exceeding those provided by standard diffraction-limited beams. | Brijesh K Singh Harel Nagar Yael Roichman Ady Arie | 2017 | Light(Science & Applications)2017，6，1： | 5 |
| 6 | Safety of gastrointestinal endoscopy with conscious sedation in obstructive sleep apnea显示文摘AIM To perform a systematic review and meta-analysis to assess the safety of conscious sedation in patients with obstructive sleep apnea(OSA).METHODS A comprehensive electronic search of MEDLINE and EMBASE was performed from inception until March 1, 2015. In an effort to include unpublished data, abstracts from prior gastroenterological society meetings as well as other reference sources were interrogated. After study selection, two authors utilizing a standardized data extraction form collected the data independently. Any disagreements between authors were resolved by consensus among four authors. The methodological quality was assessed using the Newcastle Ottawa tool for observational studies. The primary variables of interest included incidence of hypoxia, hypotension, tachycardia, and bradycardia. Continuous data were summarized as odds ratio(OR) and 95%CI and pooled using generic inverse variance under the random-effects model. Heterogeneity between pooled studies was assessed using the I2 statistic.RESULTS Initial search of MEDLINE and EMBASE identified 357 citations. A search of meeting abstracts did not yield any relevant citations. After systematic review and exclusion consensus meetings, seven studies met the a priori determined inclusion criteria. The overall methodological quality of included studies ranged from moderate to low. No significant differences between OSA patients and controls were identified among any of the study variables: Incidence of hypoxia(7 studies, 3005 patients; OR = 1.11; 95%CI: 0.73-1.11; P = 0.47; I2 = 0%), incidence of hypotension(4 studies, 2125 patients; OR = 1.10; 95%CI: 0.75-1.60; P = 0.63; I2 = 0%), incidence of tachycardia(3 studies, 2030 patients; OR = 0.94; 95%CI: 0.53-1.65; P = 0.28; I2 = 21%), and incidence of bradycardia(3 studies, 2030 patients; OR = 0.88; 95%CI: 0.63-1.22; P = 0.59; I2 = 0%).CONCLUSION OSA is not a significant risk factor for cardiopulmonary complications in patients undergoing endoscopic procedures with conscious sedation. | Christian M Andrade Brijesh Patel Meghana Vellanki Ambuj Kumar Gitanjali Vidyarthi | 2017 | World Journal of Gastrointestinal Endoscopy2017，9，11： | 4 |
| 7 | Promising drug targets and associated therapeutic interventions in Parkinson's disease显示文摘Parkinson's disease(PD) is one of the most debilitating brain diseases. Despite the availability of symptomatic treatments, response towards the health of PD patients remains scarce. To fulfil the medical needs of the PD patients, an efficacious and etiological treatment is required. In this review, we have compiled the information covering limitations of current therapeutic options in PD, novel drug targets for PD, and finally, the role of some critical beneficial natural products to control the progression of PD. | Sachchida Nand Rai Payal Singh Ritu Varshney Vivek K.Chaturvedi Emanuel Vamanu M.P.Singh Brijesh Kumar Singh | 2021 | Neural Regeneration Research2021，16，9： | 4 |
| 8 | Studies on Pongamia pinnata (L.) Pierre leaves: understanding the mechanism(s) of action in infectious diarrhea显示文摘While data are available on the effect of medicinal plants on intestinal motility and their antibacterial action, there is a paucity of information on their mode of action on various aspects of diarrheal pathogenicity, namely colonization to intestinal epithelial cells and production/action of enterotoxins. Crude decoction of dried leaves of Pongamia pinnata was evaluated for its antimicrobial (antibacterial, antigiardial and antirotaviral) effect; and its effect on production and action of enterotoxins (cholera toxin, CT; Escherichia coli labile toxin, LT; and E. coli stable toxin, ST); and adherence of enteropathogenic E. coli and invasion of enteroinvasive E. coli and Shigella flexneri to epithelial cells. The decoction had no antibacterial, antigiardial and antirotaviral activity, but reduced production of CT and bacterial invasion to epithelial cells. The observed results indicated that the crude decoction of P. pinnata has selective antidiarrheal action with efficacy against cholera and enteroinvasive bacterial strains causing bloody diarrheal episodes. | BRIJESH S. DASWANI P.G. TETALI P. ROJATKAR S.R. ANTIA N.H. BIRDI T.J. | 2006 | Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2006，7，8： | 3 |
| 9 | Effect of bioflocculants on the coagulation activity of alum for removal of trihalomethane precursors from low turbid water显示文摘Reactivity of chlorine towards hydrophobic groups present in natural organic matter(NOM)provokes the formation of carcinogenic disinfection byproducts such as trihalomethanes in chlorinated water. The present study aimed to investigate the variations in coagulant activity of alum using two different bioflocculants(coagulant aid) namely, Moringa oleifera and Cyamopsis tetragonoloba for the removal of hydrophobic fractions of NOM and subsequent chlorine consumption by treated water. Effect of dual coagulants on trihalomethane surrogate parameters such as total organic carbon, dissolved organic carbon, UV absorbing materials and prominent hydrophobic species such as phenolic groups along with aromatic chromophores, polyhydroxy aromatic moiety have also been studied. The concept of differential spectroscopy and absorbance slope index has been employed to understand the combined effects of alum-bioflocculants on the reactivity of NOM with chlorine. Our result shows that the combination of alum and C. tetragonoloba is more efficient for reducing trihalomethane surrogates from chlorinated water as compared to M. oleifera. C. tetragonoloba elicited synchronized effects of sweep coagulation and particle bridging-adsorption which eventually facilitated efficient removal of hydrophobic fractions of NOM. The variation in the mechanistic approach of bioflocculants was due to the presence of cationic charge on M. oleifera and adhesive property of C. tetragonoloba. | Tanwi Priya Abhrajyoti Tarafdar Bramha Gupta Brijesh Kumar Mishra | 2018 | Journal of Environmental Sciences2018，30，8： | 2 |
| 10 | 时域/频域的抖动测量显示文摘如今,我们访问信息的速度大幅提升,如在互联网上访问视频流、利用各种云端应用等。这个正在被构建的超快世界的基础就是高速数据链路。系统设计人员在从初始设计及测试到标准遵从等各个应用层面临着多种技术挑战。他们必须克服的挑战之一,就是指定工作能力足以满足多种相关串行通信标准(如PCI Express、USB、以太网、SATA及Infiniband)需求的时钟产生及分配器件。市场上有不同类型的时钟源及分配器件。根据性能,这些元器件通常可以分类如下: | Brijesh A Shah | 2014 | 今日电子2014，，9： | 2 |
| 11 | Classification of features selected through Optimum Index Factor (OIF) for improving classification accuracy显示文摘The present investigation was performed to determine if the features selected through Optimum Index Factor (OIF) could provide improved classification accuracy of the various categories on the satellite images of the individual years as well as stacked images of two different years as compared to all the features considered together. Further, in order to determine if there occurs increase in the classification accuracy of the different categories with corresponding increase in the OIF values of the features extracted from both the individual years' and stacked images, we performed linear regression between the producer's accuracy (PA) of the various categories with the OIF values of the different combinations of the features. The investigations demonstrated that there occurs significant improvement in the PA of two impervious categories viz. moderate built-up and low density built-up determined from the classification of the bands and principal components associated with the highest OIF value as compared to all the bands and principal components for both the individual years' and stacked images respectively. Regression analyses exhibited positive trends between the regression coeffi- cients and OIF values for the various categories determined for the individual years' and stacked images respectively signifying the prevalence of direct relationship between the increase in the information content with corresponding increase in the OIF values. The research proved that features extracted through OIF from both the individual years' and stacked images are capable of providing significantly improved PA as compared to all the features pooled together. | Nilanchal Patel Brijesh Kaushal | 2011 | Journal of Forestry Research2011，22，1： | 2 |
| 12 | Anterior segment optical coherence tomography for identifying muscle status in strabismus surgery显示文摘Dear Sir,Anterior segment optical coherence tomography(AS-OCT)finds very few indications in the domain of strabismus surgery.Current applications remain restricted to determining limbus-muscle insertion distance and anterior segment changes after strabismus surgery.We discuss two cases of operated strabismus surgery where AS-OCT | Brijesh Takkar Pradeep Sharma Ashutosh Kummar Singh Pranita Sahay | 2016 | International Journal of Ophthalmology(English edition)2016，9，6： | 2 |
| 13 | Rapid screening and distribution of bioactive compounds in different parts of Berberis petiolaris using direct analysis in real time mass spectrometry显示文摘Berberis petiolaris Wall,ex G.Don,an unexplored medicinal plant belonging to the family Berberidaceae,is a large deciduous shrub found in Western Himalaya between 1800-3000 m.Chemical profiling of fruit,leaf,root and stem was done by direct analysis in real time mass spectrometry followed by multivariate analysis for discrimination among the plant parts.The bioactive compounds,including magnoflorine,berberine,jatrorrhizine,thalifendine/berberrubine,demethyleneberberine,reticuline,8-oxoberberine,N-methyltetrahydroberberine,tetrahydropalmatine,tetrahydroberberine and palmatine,were identified by their exact mass measurement and the corresponding molecular formula of each compound.A comparative study of distribution pattern for all these bioactive alkaloids showed qualitative and quantitative variations in different parts of B.petiolaris.Principal component analysis clearly discriminated each part of B.petiolaris plant. | Awantika Singh Vikas Bajpai Mukesh Srivastava Kamal Ram Arya Brijesh Kumar | 2015 | Journal of Pharmaceutical Analysis2015，5，5： | 2 |
| 14 | Thermal Stability of Supercapacitor for Hybrid Energy Storage System in Lightweight Electric Vehicles:Simulation and Experiments显示文摘Recent research findings indicate that the non-monotonic consumption of energy from lithium-ion(Li-ion)batteries results in a higher heat generation in electrical energy storage systems.During peak demands,a higher heat generation due to high discharging current increases the temperature from 80℃ to 120℃,thereby resulting in thermal runaway.To address peak demands,an additional electrical energy storage component,namely supercapacitor(SC),is being investigated by various research groups.This paper provides insights into the capability of SCs in lightweight electric vehicles(EVs)to address peak demands using the worldwide harmonized light-duty driving test cycle(WLTC)driving profile in MATLAB/Simulink at different ambient temperatures.Simulation results indicate that temperature imposes a more prominent effect on Li-ion batteries compared with SCs under peak demand conditions.The effect of the discharging rate limit on the Li-ion battery current is studied.The result shows that SCs can accommodate the peak demands for a low discharging current limit on the battery,thereby reducing heat generation.Electrochemical impedance spectroscopy and cyclic voltammetry are performed on SCs to analyze their thermal performance at different temperatures ranging from 0℃ to 75℃ under different bias values of-0.6,0,0.6,and 1 V,respectively.The results indicate a higher specific capacitance of the SC at an optimum operation temperature of 25℃ for the studied bias.This study shows that the hybrid combination of the Li-ion battery and SC for a lightweight EV can address peak demands by reducing thermal stress on the Li-ion battery and increasing the driving range. | Vima Mali Brijesh Tripathi | 2022 | Journal of Modern Power Systems and Clean Energy2022，10，1： | 1 |
| 15 | An investigation of the modified direction feature for cursive character recognition显示文摘 | Michael B XinY L Brijesh V | 2007 | Pattern Recognition2007，40，2： | 1 |
| 16 | Temperature induced structural, electrical and optical changes in solution processed perovskite material: Application in photovoltaics显示文摘 | Brijesh Tripathi Parth Bhatt P. Chandra Kanth Pankaj Yadav Bhakti Desai Manoj Kumar Pandey Manoj Kumar | 2014 | Solar Energy Materials and Solar Cells2014，，： | 1 |
| 17 | Modeling and optimization of parameters of flow rate of paddy rice grains through the horizontal rotating cylindrical drum of drum seeder显示文摘 | Prasanna Kumar G V Brijesh Srivastava Nagesh D S | 2009 | Computers and Electronics in Agriculture2009，65，1： | 1 |
| 18 | Mineralization and toxicity reduction of textile dye neutral red in aqueous phase using BiOCl photocatalysis显示文摘 | Bhawna Sarwan Brijesh Pare A.D. Acharya S.B. Jonnalagadda | 2012 | Journal of Photochemistry & Photobiology, B: Biology2012，，： | 1 |
| 19 | Hepatic changes in sys- temic infection显示文摘 | Brijesh Srivastava Alexander Gimson | 2013 | Best Praet Res Clin Gastroenterel2013，27，： | 1 |
| 20 | Effect of varying concentration and temperature on steady and dynamic parameters of low concentration photovoltaic energy system显示文摘 | Pankaj Yadav Brijesh Tripathi Kavita Pandey Manoj Kumar | 2014 | International Journal of Electrical Power and Energy Systems2014，，： | 1 |
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