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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 | Treatment options for unstable trochanteric fractures: Screw or helical proximal femoral nail显示文摘Purpose: To compare treatment outcome of screw proximal femoral nail (PFN) system with that of a helical PFN. Methods: The study included 77 patients with closed unstable intertrochanteric fracture classified as AO 31A2 & 31A3, between June 2008 to August 2011. Inclusion criteria were: all mature skeletons above 50 years of age; closed unstable trochanteric fracture classified as AO 31A2 & A3. Exclusion criteria were: immature skeleton, pathological fracture of any cause other than osteoporosis, inability to walk inde- pendently prior to injury. Patients were randomized to 2 treatment groups based on admission sequence. Forty patients were treated with screw PFN and thirty seven were treated with helical PFN. Results: Both groups were similar in respect of time of surgery, blood loss and functional assessment and duration of hospitalization. In screw PFN group 2 patients had superficial wound infection, 1 patient had persistent hip pain and 1 patient had shortening 〉1 cm but 〈2 cm, while in helical PFN group 1 patient had superficial wound infection. Conclusion: Both screw and helical PFN are very effective implants in osteoporotic and unstable trochanteric fractures even in Indian patients where the bones are narrow and neck diameter is small. It is an implant of choice for osteooorotic and unstable trochanteric fractures. | Jeetendra Bajpai Rajesh Maheshwari Akansha Bajpai Sumit Saini | 2015 | Chinese Journal of Traumatology2015，18，6： | 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 | 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 |
| 5 | Sorptive removal of crystal violet from aqueous solution using spent tea leaves:Part I optimization of sorption conditions and kinetic studies显示文摘 | Bajpai S K Arti J | 2010 | Acta Chimica Slovenica2010，57，3： | 1 |
| 6 | Studies on the Correlation Between Structure and Adsorption of Sulfonamide Compounds显示文摘 | BAJPAI A K AJPOOT M MISHRA D D | 2000 | Colloids and Surfaces A:Physicochemical Engineering Aspects2000，168，3： | 1 |
| 7 | Application of enzymes in the pulp and paper industry显示文摘 | Bajpai P | 1999 | Biotechnology Progress1999，15，2： | 1 |
| 8 | Application of enzymes in the pulp and paper industry 显示文摘 | Bajpai P | 1999 | Biotechnol Prog1999，15，： | 1 |
| 9 | Evaluation of the prevalence and economic burden of adverse drug reactions presenting to the medical emergency department of a tertiary referral centre: a prospective study显示文摘 | Patel K Kedia M Bajpai D | 2007 | Clin Pharmacol2007，7，： | 1 |
| 10 | Investigation in orthogonal turn-milling towards better surface finish显示文摘 | Choudhury S K Bajpai J B | 2005 | Journal of Materials Processing Technology2005，170，3： | 1 |
| 11 | MK2 : a novel molecuolar target for anti - inflammatory therapy 显示文摘 | Duraisamy S Bajpai M Bughani U | 2008 | Expert Opin Ther Targets2008，12，8： | 1 |
| 12 | Morphology of the gametophytes of some species of Pellaea and Notholaena 显示文摘 | Nayar B K BajPai N | 1964 | Botanical Journal of the Linnean Society1964，59，： | 1 |
| 13 | Bioinformatically mined simple sequence repeats in UniGene of Citrus sinensis显示文摘 | Shanker A Bhargava A Bajpai R | 2007 | Scientia Horticulturae2007，113，： | 1 |
| 14 | Deinking with Enzymes: a review显示文摘 | Pratima Bajpai Pramod Bajpai K | 1998 | TappiJ1998，81，12： | 1 |
| 15 | Early impairment of left ventrieular long-axis systolic function demonstrated by reduced atrioventrieular plane displacement in patients with Marfan syndrome显示文摘 | KIOTSEKOGLOU A BAJPAI A BIJNENS B H | 2008 | Eur J of Echocardiogr2008，9，5： | 1 |
| 16 | β-Catenin serves as a clutch between low and high intercellular E-cadherin bond strengths显示文摘 | BAJPAI S FENG Y WIRTZ D | 2013 | Biophys J2013，105，10： | 1 |
| 17 | Serum-soluble urokinase receptor levels do not distinguish focal segmental glomerulosclerosis from other causes of nephrotic syndrome in children 显示文摘 | Sinha A Bajpai J Saini S | 2014 | Kidney Int2014，85，3： | 1 |
| 18 | Biophoton emission in a squeezed state from a sample of Parmelia tinctornm显示文摘 | Bajpai R P | 2004 | Physics Letters A2004，322，1： | 1 |
| 19 | Tunica vaginalis flap cover in repair of recurrent proximal urethro- cutaneous fistula:A final solution显示文摘 | Sharma N Bajpai M1 Panda SS Singh A | 2013 | Afr J Paediatr Surg2013，10，4： | 1 |
| 20 | Hybrid renewable energy systems for power generation in stand-alone applications:A review 显示文摘 | Bajpai P Dash V | 2012 | Renewable and Sustainable Energy Reviews2012，16，5： | 1 |
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