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Acrosome reaction： relevance of zona pellucida glycoproteins

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Asian Journal of Andrology 2011年第1期13卷 97-105页

作者： satish k gupta Beena Bhandari Reproductive Cell Biology Laboratory National Institute of Immunology New Delhi-110 067 India

During mammalian fertilisation, the zona pellucida （ZP） matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of the acrosome reaction （AR） in the ZP-bound spermatozoon. The AR is crucial for the penetration of the ZP matrix by spermatozoa. The ZP matrix in mice is composed of three glycoproteins designated ZP1, ZP2 and ZP3, whereas in humans, it is composed of four （ZP1, ZP2, ZP3 and ZP4）. ZP3 acts as the putative primary sperm receptor and is responsible for AR induction in mice, whereas in humans （in addition to ZP3）, ZP1 and ZP4 also induce the AR. The ability of ZP3 to induce the AR resides in its C-terminal fragment. O-linked glycans are critical for the murine ZP3-mediated AR. However, N-linked glycans of human ZP1, ZP3 and ZP4 have important roles in the induction of the AR. Studies with pharmacological inhibitors showed that the ZP3-induced AR involves the activation of the Gi-coupled receptor pathway, whereas ZP1- and ZP4-mediated ARs are independent of this pathway. The ZP3-induced AR involves the activation of T-type voltage-operated calcium channels （VOCCs）, whereas ZP1- and ZP4-induced ARs involve both T- and L-type VOCCs. To conclude, in mice, ZP3 is primarily responsible for the binding of capacitated spermatozoa to the ZP matrix and induction of the AR, whereas in humans （in addition to ZP3）, ZP1 and ZP4 also participate in these stages of fertilisation.

关键词： acrosome reaction fertilisation oocyte signalling pathways spermatozoa zona pellucida glycoproteins

Higher frequency of Yq microdeletions in sperm DNA as compared to DNA isolated from blood

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Asian Journal of Andrology 2007年第5期9卷 720-722页

作者： Rima Dada Rakesh kumar M. B. Shamsi Rajeev kumar kiran kucheria Raj k. Sharma satish k. gupta Narmada P. gupta Laboratory for Molecular Reproduction and Genetics Anatomy DepartmentAll India Institute of Medical Sciences New Delhi 29 India Urology Department All India Institute of Medical Sciences New Delhi 29 India Endocrinology Department All India Institute of Medical Sciences New Delhi 29 India ART Centre Army Research and Referral Hospital New Delhi 57 India Gamete Antigen Laboratory National Institute of Immunology New Delhi 67 India

Aim： To determine if Yq microdeletion frequency and loci of deletion are similar in two tissues （blood and sperm） of different embryological origin. Methods： The present study included 52 infertile oligozoospermic cases. In each case, DNA was isolated from blood and sperms and polymerase chain reaction （PCR） microdeletion analysis was done from genomic DNA isolated from both the tissues. The PCR products were analyzed on a 1.8% agarose gel. PCR amplifications found to be negative were repeated at least three times to confirm the deletion of a given marker. Results： Only 1 case harbored microdeletion in blood DNA, whereas 4 cases harbored microdeletion in sperm DNA. Conclusion： The frequency of Yq microdeletions is higher in germ cells as compared to blood. As the majority of infertile couples opt for assisted reproduction procreation techniques （ART）, Yq microdeletion screening from germ cells is important to understand the genetic basis of infertility, to provide comprehensive counseling and most adapted therapeutics to the infertile couple.

关键词： assisted reproductive techniques infertility semen genomic DNA Yq screening

Y chromosome microdeletions in azoospermic patients with klinefelter's syndrome

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Asian Journal of Andrology 2006年第1期8卷 81-88页

作者： Anurag Mitra Rima Dada Rajeev kumar Narmada Prasad gupta kiran kucheria satish kumar gupta Gamete Antigen Laboratory National Institute of ImmunologyAruna Asaf Ali MargNew Delhi 110067India Department of Anatomy Department of Urology All India Institute of Medical SciencesAnsari NagarNew Delhi 110029India

Aim： To study the occurrence of Y chromosome microdeletions in azoospermic patients with klinefelter＇s syndrome （kFS）. Methods： Blood and semen samples were collected from azoospermic patients with kFS （n = 14） and a control group of men of proven fertility （n = 13）. Semen analysis was done according to World Health Organization （WHO） guidelines. Blood samples were processed for karyotyping, fluorescent in situ hybridization （FISH） and measurement of plasma follicle stimulating hormone （FSH） by radioimmunoassay. To determine Y chromosome microdeletions, polymerase chain reaction （PCR） of 16 sequence tagged sites （STS） and three genes （DFFRY, XkRY and RBM1 Y） was performed on isolated genomic DNA. Testicular fine needle aspiration cytology （FNAC） was done in selected cases. Results： Y chromosome microdeletions spanning the azoospermia factor （AZF）a and AZFb loci were found in four of the 14 azoospermic patients with kFS. karyotype and FISH analysis revealed that, of the four cases showing Y chromosome microdeletion, three cases had a 47,XXY/46,XY chromosomal pattern and one case had a 46,XY/47,XXY/48,XXXY/48,XXYY chromosomal pattern. The testicular FNAC of one sample with Y chromosome microdeletion revealed Sertoli cell-only type of morphology. However, no Y chromosome microdeletions were observed in any of the 13 fertile men. All patients with kFS had elevated plasma FSH levels. Conclusion： Patients with kFS may harbor Y chromosome microdeletions and screening for these should be a part of their diagnostic work-up, particularly in those considering assisted reproductive techniques. （Asian JAndrol 2006 Jan; 8： 81-88）

关键词： azoospermia azoospermia factor follicle stimulating hormone klinefelter's syndrome Y chromosome microdeletion

Novel generation of 9H-furo[3,2-b]chromen-9-ones from (E)-3-hydroxy-2-styrylchromones by excited state intramolecular proton transfer

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Chinese Chemical Letters 2008年第7期19卷 780-782页

作者： Surinder Berar Urmila Berar satish C.gupta Ramesh C.kamboj Department of Chemistry Kurukshetra UniversityKurukshetra 136119India

Photocyclisation of substituted （E）-3-hydroxy-2-（V-methyl-2＇-phenylvinyl）-4-oxo-4H-1-benzopyrans to yield linear novel tricyclic 9H-furo[3,2-b]chromen-9-ones and angular fused tetracyclic xanthenones is described.

关键词： 9H-Furo(3,2-b)chromen-9-one Photocyclisation Xanthenones

On the mechanistic origins of maximum strength in nanocrystalline metals

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npj Computational Materials 2020年第1期6卷 393-404页

作者： Ankit gupta Jacob Gruber satish S.Rajaram Gregory B.Thompson David L.McDowell Garritt J.Tucker Colorado School of Mines Mechanical EngineeringGoldenCO 80401USA Department of Mechanical Engineering Drexel UniversityPhiladelphiaPA 19104USA Department of Metallurgical and Materials Engineering University of AlabamaTuscaloosaAL 35487USA Department of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

The maximum strength of polycrystalline metals/alloys has been suggested to occur at nanoscale grain sizes where the governing deformation mechanism transitions from dislocation plasticity to grain boundary mediated *** tremendous progress recently uncovering links between transitions in nanoscale mechanisms and peak strength,the scientific literature is mostly devoid of any quantitative support,owing to the difficulty in measuring the resolved contribution of individual mechanisms to microstructural strain *** this study,the contribution of individual nanoscale mechanisms to the overall deformation of nanocrystalline Ni is calculated from atomistic simulations leveraging continuum-based kinematic metrics to compute mechanistic contributions to microstructural strain.

关键词： strength deformation grain

Studies on impact sensitivity of nanosized trinitrotoluene (TNT) confined in silica processed by sol-gel method

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Defence Technology（防务技术） 2016年第1期12卷 46-51页

作者： s.v.ingale p.b.wagh p.u.sastry c.b.basak d.bandyopadhyay s.b.phapale satish c.gupta Applied Physics Division Bhabha Atomic Research Centre Mumbai India Solid State Physics Division Bhabha Atomic Research Centre Mumbai India Glass andAdvanced Materials Division Bhabha Atomic Research Centre Mumbai India Heavy Water Division Bhabha Atomic Research Centre Mumbai India Chemistry Division Bhabha Atomic Research Centre Mumbai India

Nano-sized trinitrotoluene(TNT) material restrained in silica gel has been prepared by using the sol-gel process to study the effect of varying porosity in gel on the sensitivity of TNT. The TNT content in the gel has been varied from 60 to 90 wt %(at fixed acetone/tetramethoxysilane ratio of 50). Also, for a fixed TNT content of 75 wt %, the pore structure in the gel has been varied by changing the ratio of silica gel precursor to the solvent. The resultant TNT–silica gel composites have been characterized using scanning electron microscopy, thermal analysis, small angle X-ray scattering and surface area analysis techniques. Impact sensitivity studies were carried out using Fall Hammer Impact Test. The results showed that the sensitivity of nanostructured explosives prepared by sol-gel process can be tailored precisely by controlling the process parameters.

关键词：溶胶-凝胶法三硝基甲苯 TNT 敏感性二氧化硅纳米溶胶-凝胶过程扫描电子显微镜

Some Aspects of Pressure Induced ω→β Transformation in Group IV B Elements

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Some Aspects of Pressure Induced ω→β Transformation in Gr...

Comparative study of multiple cancellous screws versus sliding hip screws in femoral neck fractures of young adults

18th International Conference on High Pressure Science and Technology

作者： k.D.Joshi G.Jyoti satish C.gupta S.k.Sikka High Pressure Physics Division Bhabha Atomic Research Centre Mumbai India 400085 High Pressure Physics Division Bhabha Atomic Research Centre Mumbai India 400085 High Pressure Physics Division Bhabha Atomic Research Centre Mumbai India 400085 High Pressure Physics Division Bhabha Atomic Research Centre Mumbai India 400085

＜正＞ Recently,there has been considerable interest in thetheoretical and experimental work on the pressure inducedphase transition in group IVB elements,Ti,Zr and Hf[1-3].These elements are known to undergo α （hcp） to ω(threeatom simple hexagonal phase transition at few GPa[1].Using Linear Muffin Tin Orbital （LMTO）method,Gyanchandani *** predicted new ω to β（bcc） structuraltransition in Zr and Hf[2].This was later experimentallyconfirmed[3],however,the experimental transitionpressures did not match well with *** betterunderstanding of ω→β phase transition in these elements inthe present work,we have performed more accuratecalculations employing full-potential linearised augmentedplane wave method in conjunction with generalizedgradient density approximation for exchange *** to obtaining excellent agreement between our

关键词： Transition Pressures Theoretical d-substates

来源： cnki会议评论

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Chinese Journal of Traumatology 2016年第4期19卷 209-212页

作者： Mayank gupta Rajendra kumar Arya satish kumar Vijay kumar Jain Skand Sinha Ananta kumar Naik Department of Orthopedics Post Graduate Institute of Medical Education and Research Dr Ram Manohar Lohia Hospital New Delhi 110001 India

Purpose： Both cannulated cancellous screw （CCS） and sliding hip screw （SHS） are used in femoral neck fracture fixations, hut which is superior is yet to be determined. This study was aimed to compare the clinicoradiological outcome of femoral neck fracture treated with SHS or CCS in young adults. Methods： Adults （16-60 years） with femoral neck fracture were divided into Group I fixed with SHS and Group 2 fixed with three CCS after closed reduction. Pain relief, functional recovery and postoperative radiographs at 6 weeks, 3 months, 6 months and then yearly for upto 4 years were analyzed. Results： Group 1 （n = 40） achieved radiological union at mean of Z6 months, with the union rate of 8Z5% （n = 35）, avascular necrosis （AVN） rate of 7.5% （n - 3） and mean Harris Hip Score （HHS） of 86.15 at the end of 4 years. In Group 2 （n = 45） these parameters were union at Z1 months, union rate of 82.22% （n = 37）, AVN rate of 6.67% （n = 3） and HHS of 88.65. Comparative results were statistically insignificant. Conclusion： There is no significant difference in clinicoradiological outcome between the two implants.

关键词： Femoral neck fractures Bone screws Young adult

TiO<sub>2</sub>-Polysulfone Beads for Use in Photo Oxidation of Rhodamine B

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Soft Nanoscience Letters 2012年第4期2卷 67-70页

作者： Sanjay V. Ingale Pratap B. Wagh Arvind k. Tripathi Rohit Srivastav Srivastav Imejinary k. Singh Ramesh C. Bindal satish C. gupta Applied Physics Division Bhabha Atomic Research Centre Mumbai India Chemistry Division Bhabha Atomic Research Centre Mumbai India Desalination Division Bhabha Atomic Research Centre Mumbai India

The nano sized TiO2 has been synthesized by sol gel process. The titaniumisopropaxide diluted in propanol hydrolyzed under acidic condition to form a gel. The solvent from gel pores has been extracted at ambient pressure resulting in nano sized TiO2 crystallites. The crystalline phase of TiO2 could be assigned to anatase structure. An average crystallite size is about 12 nm. The surface area of TiO2 found to be 235 m2/g. The TiO2 nanocrystallites thus produced were blended with polysulphone to form its beads for ease of operation. These beads of TiO2 were used as photo catalyst in conjunction with H2O2 oxidizer in presence of UV light (254 nm) for treating the 50 ppm Rhodamine B aqueous solution. The solution decolorized within 10 minutes resulting in disappearance of absorption peak at around 600 nm in UV spectrometry. The organic entities degrade in about 60 minutes. The beads of nano sized TiO2 could be easily recovered from the treated effluent for further use.

关键词： Photo Oxidation Rhodamine B TiO2 Beads Polysulphone Nanocrystallite