Browsing by Author "J. Kaur"

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Analysis in vitro of uterine estrogen receptor conformation of young and old rats
(Kluwer Academic Publishers, 1991) M.K. Thakur; J. Kaur
The conformation of estrogen receptor (ER) and its in vitro transformation by RNase, Urea and ATP were analysed using the uteri of young (16 weeks) and old (92 weeks) rats. Following the digestion of ER with proteolytic enzymes like trypsin and chymotrypsin and the analysis of cleaved fragments by SDS-PAGE, similar pattern is observed in both ages. In vitro transformation of ER by RNase, Urea and ATP shows that the degree of transformation is lower in old than young. Furthermore, the transformed ER from old is less capable of binding to DNA than that from young. Thus our results show that the conformation of ER probably does not change with age, but the degree of transformation and the ability of transformed receptor to bind to DNA decrease with age. © 1991 Kluwer Academic Publishers.
Candidates for twin chiral bands in Rh 102
(2014) D. Tonev; M.S. Yavahchova; N. Goutev; G. De Angelis; P. Petkov; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mohanto; A. Singh; N. Kaur; R. Garg; A. Shukla; Ts. K. Marinov; S. Brant
Excited states in Rh102, populated in the fusion-evaporation reaction Zr94(B11,3n)Rh102 at a beam energy of 36 MeV, were studied using the Indian National Gamma Array spectrometer at Inter University Accelerator Center, New Delhi. The angular correlations and the electromagnetic character of some of the gamma-ray transitions observed were investigated in detail. A new chiral candidate sister band was found. Lifetimes of exited states in both chiral candidate bands of Rh102 were measured for the first time in the A∼100 mass region by means of the Doppler-shift attenuation technique. The derived reduced transition probabilities are compared to the predictions of the two quasiparticles plus triaxial rotor model. Both experimental results and calculations do not support the presence of static chirality in Rh102. © 2014 American Physical Society.
Check for chirality in 102Rh
(2012) D. Tonev; N. Goutev; M.S. Yavahchova; P. Petkov; G. De Angelis; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mahanto; A. Singh; N. Kaur; R. Garg; A. Sukla; Ts.K. Marinov; S. Brant
Excited states in 102Rh, populated by the fusion-evaporation reaction 94Zr(11B,3n)102Rh at a beam energy of 36 MeV, were studied using the INGA spectrometer at IUAC, New Delhi. The angular correlations and the electromagnetic character of some of the gamma-ray transitions observed were investigated in details. A new chiral candidate sister band was found in the level-scheme of 102Rh. Lifetimes of exited states in 102Rh were measured by means of the Doppler-shift attenuation technique. The experimental results do not support the presence of static chirality in 102Rh. © 2012 American Institute of Physics.
Curcumin-mediated reversal of p15 gene promoter methylation: Implication in anti-neoplastic action against acute lymphoid leukaemia cell line
(Charles University, 2015) V. Sharma; A.K. Jha; A. Kumar; A. Bhatnagar; G. Narayan; J. Kaur
Curcumin has been documented to exert anticancer effects by interacting with altered proliferative and apoptotic pathways in cancer models. In this study, we evaluated the potential of curcumin to reverse promoter methylation of the p15 gene in Raji cells and its ability to induce apoptosis and genomic instability. Anti-neoplastic action of curcumin showed an augmentation in reactive oxygen species (ROS) and cell cycle arrest in G1 phase. Subsequently, curcumin-exposed Raji cells showed structural abnormalities in chromosomes. These observations suggest that curcumin also causes ROS-mediated apoptosis and genomic instability. The treatment of Raji cell line with 10 μM curcumin caused hypomethylation of the p15 promoter after six days. Hypomethylation of p15 was further found to be favoured by down-regulation of DNA methyltransferase 1 after 10 μM curcumin treatment for six days. Methylation-specific PCR suggested demethylation of the p15 promoter. Demethylation was further validated by DNA sequencing. Reverse-transcription PCR demonstrated that treatment with curcumin (10 μM) for six days led to the up-regulation of p15 and down-regulation of DNA methyltransferase 1. Furthermore, curcumin-mediated reversal of p15 promoter methylation might be potentiated by down-regulation of DNA methyltransferase 1 expression, which was supported by cell cycle analysis. Furthermore, curcumin acts as a double-pronged agent, as it caused apoptosis and promoter hypomethylation in Raji cells. © 2015, Charles University. All rights reserved.
Does chirality exist in nuclei? The case of 102Rh
(Bulgarian Academy of Sciences, 2015) M.S. Yavahchova; D. Tonev; N. Goutev; G. De Angelis; P. Petkov; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mohanto; A. Singh; N. Kaur; R. Garg; A. Sukla; Ts.K. Marinov; S. Brant
Excited states in 102Rh, populated in the fusion-evaporation reaction 94Zr(11B, 3n)102Rh at a beam energy of 36 MeV, were studied using the INGA spectrometer at IUAC, New Delhi. A new chiral candidate sister band was found. Lifetimes of exited states in 102Rh were measured for the first time by means of the Doppler-shift attenuation technique. A new band was found in the level-scheme of 102Rh. 1 band with a negative parity.
Dynamic chirality in mass regions A=105 and A=130
(Institute of Physics Publishing, 2018) M.S. Yavahchova; D. Tonev; G. De Angelis; P. Petkov; N. Goutev; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mohanto; A. Singh; N. Kaur; R. Garg; A. Shukla; R. Mateva; E. Geleva; B. Slavchev; S. Brant
Chiral symmetry is dichotomic and its spontaneous breaking by the axial angular momentum vector leads to a pair of degenerate ΔI = 1 rotational bands, called chiral doublet bands. In many cases the energy degeneracy of the chiral candidate bands has almost been observed but the transition probabilities of the analogue states have been found to be different. In the angular momentum region where chirality sets in the B(E2) values of the electromagnetic transitions deexciting analogue states of the chiral twin bands should be almost equal. Correspondingly the B(M1) values should exhibit staggering. Experimental data for two nuclei from different mass regions are compared with theoretical predictions. Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F, 4n)134Pr, while excited states in 102Rh were populated in the fusion-evaporation reaction 94Zr(11B, 3n)102Rh. Our lifetime measurements and level-scheme investigations show that there are similarities in both chiral candidates nuclei related to dynamic chirality. © Published under licence by IOP Publishing Ltd.
Effect of age on physico-chemical properties of the uterine nuclear estrogen receptors of albino rats
(1991) J. Kaur; M.K. Thakur
Estrogen receptors (ER) were extracted with high ionic strength buffer from the nuclei of uteri of young (21 weeks) and old (89 weeks) rats. Following the analysis of these receptors on a sucrose gradient and a Sephadex column, two peaks representing the two forms of receptors were obtained. The minor peak sedimented at 6.8 S with Stokes radius (RS) = 7.2 nm, molecular weight (Mr) = 204 K and frictional ratio ( f f0) = 1.71. On the other hand, the major peak sedimented at 4.1 S with RS = 3.3 nm, Mr = 57 K and f f0 = 1.18. These properties of nuclear ER were similar in both ages. Also, the half life of ER complexes from both ages at 25°C and 37°C were 135 min and 30 min, respectively. However, these complexes were retained for longer periods in the nuclei of young than old rats. Furthermore, the dissociation constant of the binding of nuclear receptors to estrogen remained constant, but the number of binding sites decreased from 1.56 in young to 1.05 pmol/mg DNA in the old. In young rats, about 61% of nuclear receptors bound to DNA-cellulose. Out of this 2 5 was eluted with 0.15 M and the remaining 3 5 with 0.5 M KCl. On contrary, only 37% of total receptors bound to DNA-cellulose in the old. Out of this 3 5 was eluted with 0.15 M and the remaining 2 5 with 0.5 M KCl. These data suggested that despite the similarity in different physicochemical properties, the number of estrogen binding sites and the retention time of ER complexes in nuclei and the ability of these complexes to bind to DNA decrease in the uterus of old age. © 1991.
Effect of post-synthetic modifications of proteins on the binding of estrogen-receptor complex to uterine nuclei of aging rats
(Kluwer Academic Publishers, 1990) J. Kaur; M.K. Thakur
The binding of estrogen-receptor (ER) complex to nuclei following post-synthetic modifications of proteins was examined in the uteri of young (18 weeks) and old (96 weeks) rats. Acetylation decreases the binding of ER complex to nuclei but methylation shows no effect on the extent of binding in both ages. On the other hand, phosphorylation enhances the binding of ER complex by two-fold in nuclei from young rats but reduces this to half in nuclei from old rats. The pattern of binding in salt-resistant nuclear fractions is similar to that in total nuclei except in methylation where old rats show about 20% higher binding as compared to the respective control. These findings suggest that post-synthetic modifications of proteins modulate the binding of ER complex to uterine nuclei in an age-specific manner. © 1990 Kluwer Academic Publishers.
Estrogen-induced synthesis of uterine proteins declines during aging
(Kluwer Academic Publishers, 1993) M.K. Thakur; J. Kaur
The synthesis of total cellular as well as acid-soluble nuclear proteins and estrogen receptor is high in the uteri of young (22 weeks) and decreases to half in old (104 weeks) rats. Administration of estrogen induces the synthesis of these proteins significantly in young but shows no remarkable effect in old rats. Interestingly, a specific cytosolic protein of 45 kDa is stimulated about two-fold after estrogen injection in young but not in old rats. These findings further establish the reduced responsiveness of uterus to estrogen in old age. © 1993 Kluwer Academic Publishers.
Examples of dynamic chirality in nuclei
(EDP Sciences, 2018) M.S. Yavahchova; D. Tonev; N. Goutev; G. De Angelis; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mahanto; A. Singh; N. Kaur; R. Garg; A. Sukla
In many cases the chirality was almost observed but the transition probabilities are different. This fact is clearly seen in the cases of 134Pr and 102Rh. In the case of chirality, the yrast and the side bands should be nearly degenerate. In the angular momentum region where chirality sets, the B(E2) values of the electromagnetic transitions deexciting analog states of the chiral twin bands should be almost equal. Correspondingly the B(M1) values should exhibit staggering. Our lifetime measurements in the cases of 134Pr and 102Rh and the theoretical analysis do not support static chirality. Chirality has mainly a dynamical character in both nuclei. In the present paper, we compare our results with the results for other chiral candidate nuclei, which fulfill static chirality conditions. © The Authors, published by EDP Sciences, 2018.
High spin spectroscopy and shears mechanism in In107
(American Physical Society, 2010) D. Negi; T. Trivedi; A. Dhal; S. Kumar; V. Kumar; S. Roy; M.K. Raju; S. Appannababu; G. Mohanto; J. Kaur; R.K. Sinha; R. Kumar; R.P. Singh; S. Muralithar; A.K. Bhati; S.C. Pancholi; R.K. Bhowmik
High spin states of In107 have been investigated using the reaction Mo94(O16,p2n)In107 at a beam energy of 70 MeV. A total of 62 new γ transitions have been placed in the level scheme and several ΔI=1 sequences and one ΔI=2 sequence have been found. Lifetime measurements using the Doppler-shift attenuation method (DSAM) have been carried out for band states of ΔI=1 and ΔI=2. A decreasing trend of B(M1) strengths with increasing spin deduced for the ΔI=1 band indicates the presence of a shears mechanism. The experimental data for this band are compared with the tilted axis cranking (TAC) calculations. The ΔI=2 band has been found to be a deformed band with β2~0.2. © 2010 The American Physical Society.
In a search for a chiral symmetry in 102Rh
(Institute of Physics Publishing, 2014) M.S. Yavahchova; D. Tonev; N. Goutev; P. Petkov; G. De Angelis; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mohanto; A. Singh; N. Kaur; R. Garg; A. Sukla; Ts K. Marinov; S. Brant
Excited states in 102Rh were populated in the fusion-evaporation reaction 94Zr(nB, 3n)102Rh at a beam energy of 36 MeV, using the INGA spectrometer at IUAC, New Delhi. The angular correlations and the electromagnetic character of some of the γ-ray transitions observed in 102Rh were investigated in detail. A new candidate for a chiral twin band was identified in 102Rh for the first time.
Investigation of an intruder band in 45 Sc via coulomb excitation ∗
(Jagellonian University, 2019) M. Matejska-Minda; R. Kumar; P.J. Napiorkowski; M. Saxena; S. Dutt; A. Agarwal; I. Ahmed; S. Bhattacharya; A. Jhingan; J. Kaur; M. Kicińska-Habior; M. Kumar; S. Kumar; D. Kumar; V. Nanal; R. Palit; N.K. Rai; M. Shuaib; A. Sood; A. Stolarz; T. Trivedi; A.K. Tyagi; R.K. Bhowmik; H.J. Wollersheim
In order to gain further information on the electromagnetic properties of the low-lying states in 45 Sc, a Coulomb excitation measurement was carried out at the IUAC, New Delhi. The 45 Sc target nuclei were Coulomb excited by the 70 MeV 32 S beam from the 15UD tandem accelerator. The γ-rays depopulating Coulomb excited states in 45 Sc were detected by four Clover detectors in coincidence with the forward scattered ions. The main aim of the experiment was to determine the B(E3; 7/2 − → 3/2 + ) and B(E3; 7/2 − → 5/2 + ) transition probabilities, as well as the transitional electromagnetic matrix elements for low-lying intruder states. © 2019 Jagellonian University. All Rights Reserved.
Investigation of chirality in the case of 102Rh
(Institute of Physics Publishing, 2016) M.S. Yavahchova; D. Tonev; N. Goutev; G. De Angelis; P. Petkov; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mahanto; A. Singh; N. Kaur; R. Garg; A. Sukla; Ts. K. Marinov; R.R. Mateeva; S. Brant
Excited states in 102Rh were populated in the fusion-evaporation reaction 94Zr(11B, 3n)102Rh at a beam energy of 36 MeV using the INGA spectrometer at IUAC, New Delhi. The angular correlations and the electromagnetic character of some of the gamma-ray transitions observed were investigated in details. A new chiral candidate sister band was found. Lifetimes of exited states in 102Rh were measured using the Doppler-shift attenuation technique and the derived reduced transition probabilities are compared to the predictions of the Two Quasiparticles Plus Triaxial Rotor model. © Published under licence by IOP Publishing Ltd.
Level scheme investigation of 102Rh
(Institute of Physics Publishing, 2012) N. Goutev; M.S. Yavahchova; D. Tonev; G. De Angelis; P. Petkov; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mahanto; A. Singh; N. Kaur; R. Garg; A. Sukla; Ts.K. Marinov; S. Brant
Excited states in102Rh were populated in the fusion-evaporation reaction 96Zr(11B, 3n)102 Rh. The angular correlations and the electromagnetic character of some of the gamma-ray transitions observed were investigated in detail. A new chiral candidate sister band was found in the level-scheme of 102Rh.
Lifetime measurements in mass regions A=100 and A=130 as a test for chirality in nuclear systems
(EDP Sciences, 2016) D. Tonev; M.S. Yavahchova; G. De Angelis; S. Brant; S. Frauendorf; P. Petkov; A. Dewald; Q. Zhong; D. Curien; N. Goutev; R.K. Bhowmik; R.P. Singh; S. Muralithar; N. Madhavan; R. Kumar; M. Kumar Raju; J. Kaur; G. Mahanto; A. Singh; N. Kaur; R. Garg; A. Sukla; E. Geleva; Ts. K. Marinov
Two odd-odd nuclei from the A ∼ 100 and A ∼ 130 regions, namely 102Rh and 134Pr have been studied in search for chiral doublet bands via 94Zr(11B,3n)102Rh and 119Sn(19F,4n)134Pr reactions, respectively. Two nearly degenerate bands built on the πg9/2 ⊗ νh11/2 configuration have been identified in 102Rh and on the πg11/2 ⊗ νh11/2 configuration for 134Pr. Lifetimes of excited nuclear states were measured using Dopplershift attenuation method and recoil distance Doppler-shift method. The deexciting gamma rays were registered by the Indian National Gamma Array for 102Rh and using the EUROBALL IV detector array with an inner Bismuth Germanate (BGO) ball for 134Pr, respectively. Polarization and angular correlation measurements have been performed to establish the spin and parity assignments for these bands. The derived reduced transition probabilities are compared to the predicitons of the two quasiparticles + triaxial rotor and interacting boson fermion-fermion models. © 2016 Owned by the authors, published by EDP Sciences.
Methylation of DNA and its modulation by estrogen in the uterus of aging rats.
(1992) M.K. Thakur; J. Kaur
The effect of estrogen on methylation of DNA from the uteri of young (20 weeks) and old (96 weeks) female Wistar rats has been examined by isoschizomeric restriction enzymes and HPLC analysis. In vitro methylation of DNA is significantly higher in the uteri of young rats as compared to old ones. This is reduced by estrogen to greater extent in young than in old age. Furthermore, the digestion of DNA with EcoRI+Msp I shows a distinct 1.2 kb band only in young control. Such band is absent in old control and estrogen-treated sets of both age groups. The HPLC data further reveal that the level of 5-methyl cytosine is high in young and decreases by nearly 18% in old. Estrogen lowers the level of 5-methyl cytosine by 8% in young but shows no effect in the old. Such age-dependent changes in the methylation of DNA brought by estrogen in the rat uterus attribute to alterations in gene expression during aging.
Re-measurement of reduced transition probabilities in 132ba
(Jagellonian University, 2018) S. Dutta; M. Saxena; R. Kumar; A. Jhingan; A. Agarwal; A. Banerjee; R.K. Bhowmik; C. Joshi; J. Kaur; A. Kumar; M. Matejska-Minda; V. Mishra; I.A. Rizvi; A. Stolarz; H.J. Wollersheim; P.J. Napiorkowski
Reduced transition probabilities between the low-lying states of 132Ba were measured using the Coulomb excitation technique. The experiment was performed at Inter University Accelerator Center (IUAC), New Delhi using a 58Ni beam of 175 MeV energy to Coulomb excite the 132Ba nuclei. In addition to the 2+1 state, other states in 132Ba, such as 2+2 and 4+1 , were populated, the latter for the first time using Coulomb excitation. A set of matrix elements was extracted for the transitions between these levels. These values were determined relative to 134Ba excitations to minimize the systematic errors. A B(E2; 0+gs → 2+1) value of 1.088(85) e2 b2 was determined, corresponding to -54:5 single-particle units. © 2018 Jagellonian University. All rights reserved.
Revised lifetime of the 11/2- state in 45Sc via coulomb excitation
(Jagellonian University, 2020) M. Matejska-Minda; P.J. Napiorkowski; R. Kumar; M. Saxena; S. Dutt; A. Agarwal; I. Ahmed; S. Bhattacharya; A. Jhingan; J. Kaur; M. Kicińska-Habior; M. Kumar; S. Kumar; D. Kumar; V. Nanal; R. Palit; N.K. Rai; M. Shuaib; A. Sood; A. Stolarz; T. Trivedi; A.K. Tyagi; R.K. Bhowmik; H.J. Wollersheim
A Coulomb-excitation measurement to study low-energy electromagnetic properties of 45Sc has been performed at the IUAC facility in New Delhi, India using a 70 MeV 32S projectile from the 15UD tandem accelerator. The preliminary value of the reduced transition probability B(E2; 11/2- → 7/2-) and the resulting lifetime for the 11/2- state at 1237 keV were determined using the GOSIA code. © 2020 Jagellonian University. All rights reserved.
Shears mechanism in 109In
(American Physical Society, 2012) D. Negi; T. Trivedi; A. Dhal; S. Kumar; V. Kumar; S. Roy; M.K. Raju; S. Appannababu; G. Mohanto; J. Kaur; R.K. Sinha; D. Choudhury; D. Singh; R. Kumar; R.P. Singh; S. Muralithar; A.K. Bhati; S.C. Pancholi; R.K. Bhowmik
High spin states of 109In were investigated using the reaction 96Zr(19F, 6n)109In at a beam energy of 105 MeV. New level sequences have been found in this nucleus. In an earlier known band, the ordering of some of the transitions have been changed and assigned a three-quasiparticle π(g9/2) -1 âŠ - ν[h11/2(d5/2/g7 /2)] configuration. Similar three-quasiparticle bands have also been found earlier in lighter mass 105In and 107In nuclei. Systematics of these bands in 105In, 107In, and 109In nuclei are discussed in the present work within the framework of the tilted axis cranking model. © 2012 American Physical Society.