Displaying publications 1 - 20 of 35 in total

  1. Chatterjee A, Chatterjee R
    Acta Anat (Basel), 1992;144(4):329-31.
    PMID: 1414199
    Surgical reduction of luteal tissue to about 20% of its total mass on day 5 pc was found to maintain gestation till term. A high degree of fetal loss was, however, evident. An identical surgical manipulation at the end of maximal luteal maturity, that is, on day 16 pc, resulted in normal maintenance of gestation. Fetal growth and their survival rate were found to be comparable to controls. An exclusive surgical extirpation of corpora lutea, on the other hand, either on day 16, 17, 18 or 19 was found to cause 100% fetal loss by day 23. However, progesterone replacement therapy concurrently with surgical luteal ablation till day 20, or surgical extirpation of the entire luteal mass when shifted on day 20, led the pregnancy to term. Present experimental findings, therefore, suggest that only about 20% of the functionally matured luteal mass until day 20 is essentially enough to maintain an ideal pregnancy status till term.
  2. Abd-Aziz, N.A.A., Chatterjee, A., Chatterjee, R., Durairajanayagam, D.
    ASM Science Journal, 2014;8(2):117-124.
    Elevated glucocorticoid levels during stressed conditions have been demonstrated to impair reproductive function in rats. In our previous study investigating the dose-related effects of corticosterone (CORT) on the fertilising capacity of epididymal sperm in surgically-manipulated rats, we found that 25 mg/kg/day of CORT given subcutaneously for seven consecutive days significantly decreased the number of implantation sites and increased intrauterine embryonic loss compared to controls. Based on these findings, the current study aims to elucidate the possible mechanisms of action of CORT-induced stress on impaired sperm fertility in rats. Results of the present study showed that compared to controls, 25 mg/kg/day of CORT given subcutaneously for 7 consecutive days significantly increased the level of plasma malondialdehyde (MDA) with corresponding attenuated levels of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activities. Plasma adrenocorticotropin (ACTH) and testosterone levels were also found to be decreased in CORTtreated rats. These findings suggest that CORT-induced oxidative stress and exert an inhibitory effect at the hypothalamic-pituitary-gonadal (HPG) axis, as evidenced by increased lipid peroxidation, reduced enzymatic antioxidant activities, and decreased testosterone production. These subsequently result in decreased fertilising capacity of epididymal sperm leading to poor pregnancy outcomes.
  3. Chatterjee A, Singh R, Chatterjee R
    Pharmacol. Res., 1993 May-Jun;27(4):359-64.
    PMID: 8367382
    Dexamethasone blocks aromatase and phospholipase A2 enzyme activities that are essentially involved in the formation of oestrogens and prostaglandins, the key chemicals to initiate parturition. The present study was undertaken to determine whether dexamethasone, a potent glucocorticoid, could prolong gestation and/or delay parturition in rats. Dexamethasone at 0.5 mg/rat/day from Day 19 through Day 21 of pregnancy consistently prolonged gestation. Only 36% of the pregnant rats had labour with an extended parturition time. Foetal mortality rate was also high. The remaining 64% pregnant rats that did not deliver showed intrauterine foetal death and resorption. Concomitant injection of oestradiol cyclopentylpropionate or prostaglandin F2 alpha on Day 19 effectively reversed the deleterious effects of dexamethasone. 100% of the pregnant rats had successful labour at term. The parturition time and foetal mortality rate were not different from controls. The results, therefore, indicate that an excess glucocorticoid that initiates parturition in sheep conversely prolongs gestation and delays parturition in rats.
  4. Zakaria R, Ismail Z, Chatterjee A
    Pharmacol. Res., 2000 Aug;42(2):183-6.
    PMID: 10887050
    Reproductive dysfunction in the female diabetic rat is associated with impaired hypothalamic-hypophyseal system, anovulation, insufficiency of ovarian steroidogenesis and spontaneous failure of pregnancy. Formation of decidua, the highly modified endometrium of pregnancy and pseudopregnancy could only be achieved when the uterus was sensitized by a sequence of oestrogen and progesterone. In this study, we examined whether the impaired expression of endometrial decidualization in the pseudopregnant rat is linked with diabetes-associated hypersecretion of testosterone. Rats were made pseudopregnant by sterile mating. Diabetes was induced by streptozotocin on day 1 p.c. Deciduogenic stimulus was given on day 5 p.c. Treatment of cyproterone acetate (10 mg kg(-1)) was scheduled from day 5 through day 9 p.c. Animals were killed on day 10 p.c, and the degree of endometrial decidual growth, plasma levels of oestradiol, progesterone, ACTH and testosterone were determined. Results showed that compared to controls there was a concomitant drop in endometrial decidual growth concurrently with impaired levels of oestradiol and progesterone in diabetic pseudopregnant rats. ACTH and testosterone levels were, however, profoundly elevated. Cyproterone acetate treatment in the diabetic pseudopregnant rat resulted in a simultaneous elevation of oestradiol and progesterone, which eventually helped the endometrial differentiation to decidua in the diabetic pseudopregnant rat parallel to controls. Present experimental data suggest that diabetes-associated impaired endometrial decidualization in the pseudopregnant rat is possibly caused by testosterone-induced oestrogen deficiency.
  5. Rietveld LC, Siri JG, Chakravarty I, Arsénio AM, Biswas R, Chatterjee A
    Environ Health, 2016;15 Suppl 1:31.
    PMID: 26960393 DOI: 10.1186/s12940-016-0107-2
    As human populations become more and more urban, decision-makers at all levels face new challenges related to both the scale of service provision and the increasing complexity of cities and the networks that connect them. These challenges may take on unique aspects in cities with different cultures, political and institutional frameworks, and at different levels of development, but they frequently have in common an origin in the interaction of human and environmental systems and the feedback relationships that govern their dynamic evolution. Accordingly, systems approaches are becoming recognized as critical to understanding and addressing such complex problems, including those related to human health and wellbeing. Management of water resources in and for cities is one area where such approaches hold real promise.
  6. Siti Norashikin MT, Ghosh S, Chatterjee R, Rajikin MH, Chatterjee A
    Reprod. Med. Biol., 2014 Jul;13(3):135-141.
    PMID: 29699157 DOI: 10.1007/s12522-013-0174-9
    Purpose: The present study aims to investigate the effects of nicotine on the endometrial decidual growth and levels of estrogen and progesterone in pseudopregnant rats.

    Methods: Pseudopregnancy (pc) was induced in cyclic Sprague-Dawley rats by sterile mating. Subcutaneous injection of nicotine tartrate (7.5 mg/kg/day) was scheduled from day 1 through day 5, day 5 through day 9 or day 1 through day 9 of pc. In another group of pseudopregnant rats, concomitant treatment of nicotine tartrate concurrently with progesterone (2 mg/day) was scheduled from day 1 through day 9 pc. Control groups received subcutaneous injections of vehicle only. Endometrial decidualization was induced on day 5 pc. On day 10 pc, animals were sacrificed.The degree of decidual growth and circulating levels of estrogen and progesterone were measured.

    Results: The decidual growth in all the first three nicotine-treated groups of animals was significantly reduced, particularly in the animals treated with nicotine from day 1 through day 9 pc. Plasma estrogen levels were significantly elevated in animals treated with nicotine from day 1 through day 9 pc. Conversely, levels of plasma progesterone were found to be significantly attenuated in the same group of nicotine-treated animals compared to controls. Exogenous replacement of progesterone, however, caused a higher degree of endometrial decidualization compared to the nicotine-treated group but it was slightly less than when compared to control.

    Conclusions: In conclusion, nicotine-induced progesterone deficiency with a corresponding elevation of estrogen may possibly attenuate the degree of endometrial decidualization in pseudopregnant rats.

  7. Chatterjee A, Sicheritz-Pontén T, Yadav R, Kondabagil K
    Sci Rep, 2019 Mar 06;9(1):3690.
    PMID: 30842490 DOI: 10.1038/s41598-019-40171-y
    We report the detection of genomic signatures of giant viruses (GVs) in the metagenomes of three environment samples from Mumbai, India, namely, a pre-filter of a household water purifier, a sludge sample from wastewater treatment plant (WWTP), and a drying bed sample of the same WWTP. The de novo assembled contigs of each sample yielded 700 to 2000 maximum unique matches with the GV genomic database. In all three samples, the maximum number of reads aligned to Pandoraviridae, followed by Phycodnaviridae, Mimiviridae, Iridoviridae, and other Megaviruses. We also isolated GVs from every environmental sample (n = 20) we tested using co-culture of the sample with Acanthomoeba castellanii. From this, four randomly selected GVs were subjected to the genomic characterization that showed remarkable cladistic homology with the three GV families viz., Mimivirirdae (Mimivirus Bombay [MVB]), Megaviruses (Powai lake megavirus [PLMV] and Bandra megavius [BAV]), and Marseilleviridae (Kurlavirus [KV]). All 4 isolates exhibited remarkable genomic identity with respective GV families. Functionally, the genomes were indistinguishable from other previously reported GVs, encoding nearly all COGs across extant family members. Further, the uncanny genomic homogeneity exhibited by individual GV families across distant geographies indicate their yet to be ascertained ecological significance.
  8. Abd Aziz NAA, Chatterjee A, Chatterjee R, Durairajanayagam D
    Andrologia, 2019 Apr;51(3):e13199.
    PMID: 30461035 DOI: 10.1111/and.13199
    This study examined whether tocotrienol supplementation to corticosterone-treated male rats could prevent foetal loss in females upon their mating. Epididymides of adult male Sprague-Dawley (SD) rats with proven fertility were surgically separated at the testis-caput junction. Twenty-four hours post-surgery, these animals received for 7 days either: tocopherol-stripped corn oil (Control), corticosterone 25 mg/kg s.c. (CORT), CORT 25 mg/kg s.c. and tocotrienol-rich fraction (TRF) 100 mg/kg orally (CORT + TRF) or TRF 100 mg/kg orally (TRF). On day 8, males were cohabited with proestrus females. A spermatozoa-positive vaginal smear indicated pregnancy. Males were euthanised for analysis of testosterone and antioxidant activities. Reproductive organs were weighed. On day 8 of pregnancy, females were laparotomised to count the number of implantation sites. Pregnancy was continued until term. Number of pups delivered and their weights were determined. Data were analysed using ANOVA. Malondialdehyde levels were significantly lower in CORT + TRF group compared with CORT group. Enzymatic antioxidant activities, testosterone level and reproductive organ weights were significantly higher in CORT + TRF group compared with CORT group. Number of implantation sites and live pups delivered, and their birth weights from females mated with CORT + TRF males were significantly higher compared to CORT group. Therefore, TRF prevents foetal loss in females mated with CORT + TRF-treated males.
  9. Kamsani YS, Rajikin MH, Mohamed Nor Khan NA, Abdul Satar N, Chatterjee A
    Med Sci Monit Basic Res, 2013;19:87-92.
    PMID: 23462735 DOI: 10.12659/MSMBR.883822
    This study aimed to evaluate the adverse effects of various doses of nicotine and protective effects of different concentrations of gamma-tocotrienol (gamma-TCT) on in vitro embryonic development and lipid peroxidation in mice.
  10. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys. Rev. Lett., 2015 Feb 6;114(5):051801.
    PMID: 25699433
    A study of vector boson scattering in pp collisions at a center-of-mass energy of 8 TeV is presented. The data sample corresponds to an integrated luminosity of 19.4  fb(-1) collected with the CMS detector. Candidate events are selected with exactly two leptons of the same charge, two jets with large rapidity separation and high dijet mass, and moderate missing transverse energy. The signal region is expected to be dominated by electroweak same-sign W-boson pair production. The observation agrees with the standard model prediction. The observed significance is 2.0 standard deviations, where a significance of 3.1 standard deviations is expected based on the standard model. Cross section measurements for W(±)W(±) and WZ processes in the fiducial region are reported. Bounds on the structure of quartic vector-boson interactions are given in the framework of dimension-eight effective field theory operators, as well as limits on the production of doubly charged Higgs bosons.
  11. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys. Rev. Lett., 2015 Mar 13;114(10):101801.
    PMID: 25815923
    Results are presented from a search for new decaying massive particles whose presence is inferred from an imbalance in transverse momentum and which are produced in association with a single top quark that decays into a bottom quark and two light quarks. The measurement is performed using 19.7  fb^{-1} of data from proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No deviations from the standard model predictions are observed and lower limits are set on the masses of new invisible bosons. In particular, scalar and vector particles, with masses below 330 and 650 GeV, respectively, are excluded at 95% confidence level, thereby substantially extending a previous limit published by the CDF Collaboration.
  12. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys. Rev. Lett., 2015 Feb 13;114(6):061801.
    PMID: 25723204
    A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at √[s]=8  TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7  fb(-1). Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-μ final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to cτ=2  cm, excluding masses below 790 GeV at 95% confidence level.
  13. Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Phys. Rev. Lett., 2014 Apr 25;112(16):161802.
    PMID: 24815637
    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7  fb-1 of proton-proton collision data at s=8  TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass.
  14. Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014;74(8):2980.
    PMID: 25814906
    A search for invisible decays of Higgs bosons is performed using the vector boson fusion and associated ZH production modes. In the ZH mode, the Z boson is required to decay to a pair of charged leptons or a [Formula: see text] quark pair. The searches use the 8 [Formula: see text] pp collision dataset collected by the CMS detector at the LHC, corresponding to an integrated luminosity of up to 19.7 [Formula: see text]. Certain channels include data from 7 [Formula: see text] collisions corresponding to an integrated luminosity of 4.9 [Formula: see text]. The searches are sensitive to non-standard-model invisible decays of the recently observed Higgs boson, as well as additional Higgs bosons with similar production modes and large invisible branching fractions. In all channels, the observed data are consistent with the expected standard model backgrounds. Limits are set on the production cross section times invisible branching fraction, as a function of the Higgs boson mass, for the vector boson fusion and ZH production modes. By combining all channels, and assuming standard model Higgs boson cross sections and acceptances, the observed (expected) upper limit on the invisible branching fraction at [Formula: see text] [Formula: see text] is found to be 0.58 (0.44) at 95 % confidence level. We interpret this limit in terms of a Higgs-portal model of dark matter interactions.
  15. CMS Collaboration, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014;74(9):3060.
    PMID: 25814914
    A measurement of the cross section for the production of top quark-antiquark pairs ([Formula: see text]) in association with a vector boson V (W or Z) in proton-proton collisions at [Formula: see text][Formula: see text] is presented. The results are based on a dataset corresponding to an integrated luminosity of 19.5 fb[Formula: see text] recorded with the CMS detector at the LHC. The measurement is performed in three leptonic (e and [Formula: see text]) channels: a same-sign dilepton analysis targeting [Formula: see text] events, and trilepton and four-lepton analyses designed for [Formula: see text] events. In the same-sign dilepton channel, the [Formula: see text] cross section is measured as [Formula: see text], corresponding to a significance of 1.6 standard deviations over the background-only hypothesis. Combining the trilepton and four-lepton channels, a direct measurement of the [Formula: see text] cross section, [Formula: see text], is obtained with a significance of 3.1 standard deviations. The measured cross sections are compatible with standard model predictions within their experimental uncertainties. The inclusive [Formula: see text] process is observed with a significance of 3.7 standard deviations from the combination of all three leptonic channels.
  16. CMS Collaboration, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014;74(9):3036.
    PMID: 25814912
    Searches for the direct electroweak production of supersymmetric charginos, neutralinos, and sleptons in a variety of signatures with leptons and [Formula: see text], [Formula: see text], and Higgs bosons are presented. Results are based on a sample of proton-proton collision data collected at center-of-mass energy [Formula: see text] with the CMS detector in 2012, corresponding to an integrated luminosity of 19.5 [Formula: see text]. The observed event rates are in agreement with expectations from the standard model. These results probe charginos and neutralinos with masses up to 720 [Formula: see text], and sleptons up to 260 [Formula: see text], depending on the model details.
  17. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2014;74(10):3076.
    PMID: 25814871
    Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton collisions during the 2011 and 2012 LHC running periods. The data samples correspond to integrated luminosities of 5.1[Formula: see text]at [Formula: see text] and 19.7[Formula: see text]at 8[Formula: see text] . A clear signal is observed in the diphoton channel at a mass close to 125[Formula: see text] with a local significance of [Formula: see text], where a significance of [Formula: see text] is expected for the standard model Higgs boson. The mass is measured to be [Formula: see text] , and the best-fit signal strength relative to the standard model prediction is [Formula: see text][Formula: see text][Formula: see text]. Additional measurements include the signal strength modifiers associated with different production mechanisms, and hypothesis tests between spin-0 and spin-2 models.
  18. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2016 Feb 19;116(7):071801.
    PMID: 26943527 DOI: 10.1103/PhysRevLett.116.071801
    A search for narrow resonances in proton-proton collisions at sqrt[s]=13  TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4  fb^{-1}. The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W^{'} bosons below 2.6 TeV. These results significantly extend previously published limits.
  19. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2016 Jan 22;116(3):032301.
    PMID: 26849587 DOI: 10.1103/PhysRevLett.116.032301
    The production cross sections of the B^{+}, B^{0}, and B_{s}^{0} mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy sqrt[s_{NN}]=5.02  TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6  nb^{-1}. The production cross sections are measured in the transverse momentum range between 10 and 60  GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions.
  20. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015;75(6):251.
    PMID: 26097407
    A search for a standard model Higgs boson produced in association with a top-quark pair and decaying to bottom quarks is presented. Events with hadronic jets and one or two oppositely charged leptons are selected from a data sample corresponding to an integrated luminosity of 19.5[Formula: see text] collected by the CMS experiment at the LHC in [Formula: see text] collisions at a centre-of-mass energy of 8[Formula: see text]. In order to separate the signal from the larger [Formula: see text]  + jets background, this analysis uses a matrix element method that assigns a probability density value to each reconstructed event under signal or background hypotheses. The ratio between the two values is used in a maximum likelihood fit to extract the signal yield. The results are presented in terms of the measured signal strength modifier, [Formula: see text], relative to the standard model prediction for a Higgs boson mass of 125[Formula: see text]. The observed (expected) exclusion limit at a 95 % confidence level is [Formula: see text] (3.3), corresponding to a best fit value [Formula: see text].
Related Terms
Contact Us

Please provide feedback to Administrator (tengcl@gmail.com)

External Links