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1.
Phys Rev Lett ; 127(13): 139902, 2021 Sep 24.
Article in English | MEDLINE | ID: mdl-34623869

ABSTRACT

This corrects the article DOI: 10.1103/PhysRevLett.114.082501.

2.
Phys Rev Lett ; 124(5): 052501, 2020 Feb 07.
Article in English | MEDLINE | ID: mdl-32083900

ABSTRACT

The rare phenomenon of nuclear wobbling motion has been investigated in the nucleus ^{187}Au. A longitudinal wobbling-bands pair has been identified and clearly distinguished from the associated signature-partner band on the basis of angular distribution measurements. Theoretical calculations in the framework of the particle rotor model are found to agree well with the experimental observations. This is the first experimental evidence for longitudinal wobbling bands where the expected signature partner band has also been identified, and establishes this exotic collective mode as a general phenomenon over the nuclear chart.

3.
Phys Rev Lett ; 124(2): 022501, 2020 Jan 17.
Article in English | MEDLINE | ID: mdl-32004026

ABSTRACT

Spectroscopic factors of neutron-hole and proton-hole states in ^{131}Sn and ^{131}In, respectively, were measured using one-nucleon removal reactions from doubly magic ^{132}Sn at relativistic energies. For ^{131}In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5/2^{-} state at 3275(50) keV to the known 1/2^{-} level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of single-hole strength in ^{131}Sn and ^{131}In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling model and to experimental information for single-hole states in the stable doubly magic nucleus ^{208}Pb.

4.
Phys Rev Lett ; 118(17): 172501, 2017 Apr 28.
Article in English | MEDLINE | ID: mdl-28498679

ABSTRACT

The (^{10}Be,^{10}B^{*}[1.74 MeV]) charge-exchange reaction at 100 AMeV is presented as a new probe for isolating the isovector (ΔT=1) nonspin-transfer (ΔS=0) response of nuclei, with ^{28}Si being the first nucleus studied. By using a secondary ^{10}Be beam produced by fast fragmentation of ^{18}O nuclei at the NSCL Coupled Cyclotron Facility, applying the dispersion-matching technique with the S800 magnetic spectrometer to determine the excitation energy in ^{28}Al, and performing high-resolution γ-ray tracking with the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to identify the 1022-keV γ ray associated with the decay from the 1.74-MeV T=1 isobaric analog state in ^{10}B, a ΔS=0 excitation-energy spectrum in ^{28}Al was extracted. Monopole and dipole contributions were determined through a multipole-decomposition analysis, and the isovector giant dipole resonance and isovector giant monopole resonance (IVGMR) were identified. The results show that this probe is a powerful tool for studying the elusive IVGMR, which is of interest for performing stringent tests of modern density functional theories at high excitation energies and for constraining the bulk properties of nuclei and nuclear matter. The extracted distributions were compared with theoretical calculations based on the normal-modes formalism and the proton-neutron relativistic time-blocking approximation. Calculated cross sections based on these strengths underestimate the data by about a factor of 2, which likely indicates deficiencies in the reaction calculations based on the distorted wave Born approximation.

5.
Phys Rev Lett ; 114(8): 082501, 2015 Feb 27.
Article in English | MEDLINE | ID: mdl-25768759

ABSTRACT

A pair of transverse wobbling bands is observed in the nucleus ^{135}Pr. The wobbling is characterized by ΔI=1, E2 transitions between the bands, and a decrease in the wobbling energy confirms its transverse nature. Additionally, a transition from transverse wobbling to a three-quasiparticle band comprised of strong magnetic dipole transitions is observed. These observations conform well to results from calculations with the tilted axis cranking model and the quasiparticle rotor model.

6.
Phys Rev Lett ; 113(3): 032504, 2014 Jul 18.
Article in English | MEDLINE | ID: mdl-25083638

ABSTRACT

The isoscalar monopole response has been measured in the unstable nucleus (68)Ni using inelastic alpha scattering at 50A MeV in inverse kinematics with the active target MAYA at GANIL. The isoscalar giant monopole resonance (ISGMR) centroid was determined to be 21.1 ± 1.9 MeV and indications for a soft monopole mode are provided for the first time at 12.9 ± 1.0 MeV. Analysis of the corresponding angular distributions using distorted-wave-born approximation with random-phase approximation transition densities indicates that the L = 0 multipolarity dominates the cross section for the ISGMR and significantly contributes to the low-energy mode. The L=0 part of this low-energy mode, the soft monopole mode, is dominated by neutron excitations. This demonstrates the relevance of inelastic alpha scattering in inverse kinematics in order to probe both the ISGMR and isoscalar soft modes in neutron-rich nuclei.

7.
Phys Rev Lett ; 112(11): 112503, 2014 Mar 21.
Article in English | MEDLINE | ID: mdl-24702356

ABSTRACT

Excited states in the neutron-rich N = 38, 36 nuclei (60)Ti and (58)Ti were populated in nucleon-removal reactions from (61)V projectiles at 90 MeV/nucleon. The γ-ray transitions from such states in these Ti isotopes were detected with the advanced γ-ray tracking array GRETINA and were corrected event by event for large Doppler shifts (v/c ∼ 0.4) using the γ-ray interaction points deduced from online signal decomposition. The new data indicate that a steep decrease in quadrupole collectivity occurs when moving from neutron-rich N = 36, 38 Fe and Cr toward the Ti and Ca isotones. In fact, (58,60)Ti provide some of the most neutron-rich benchmarks accessible today for calculations attempting to determine the structure of the potentially doubly magic nucleus (60)Ca.

8.
Phys Rev Lett ; 110(10): 102501, 2013 Mar 08.
Article in English | MEDLINE | ID: mdl-23521253

ABSTRACT

Low-lying collective excitations in even-even vibrational and transitional nuclei may be described semiclassically as quadrupole running waves on the surface of the nucleus ("tidal waves"), and the observed vibrational-rotational behavior can be thought of as resulting from a rotating condensate of interacting d bosons. These concepts have been investigated by measuring lifetimes of the levels in the yrast band of the (102)Pd nucleus with the Doppler shift attenuation method. The extracted B(E2) reduced transition probabilities for the yrast band display a monotonic increase with spin, in agreement with the interpretation based on rotation-induced condensation of aligned d bosons.

9.
Phys Rev Lett ; 110(17): 172504, 2013 Apr 26.
Article in English | MEDLINE | ID: mdl-23679714

ABSTRACT

Two distinct sets of chiral-partner bands have been identified in the nucleus 133Ce. They constitute a multiple chiral doublet, a phenomenon predicted by relativistic mean field (RMF) calculations and observed experimentally here for the first time. The properties of these chiral bands are in good agreement with results of calculations based on a combination of the constrained triaxial RMF theory and the particle-rotor model.

10.
West Indian Med J ; 64(4): 456-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26624607
11.
J Assoc Physicians India ; 56: 581-6, 2008 Aug.
Article in English | MEDLINE | ID: mdl-19051701

ABSTRACT

AIMS: To compare the carotid intimal-medial thickness in type 2 diabetics with and without coronary artery disease (CAD), and to correlate the intimal-medial thickness (IMT) with known coronary risk factors. METHODS: One hundred and eleven patients of type 2 diabetes were recruited for the study. History and physical examination were recorded. Laboratory investigations included fasting and 2-hour post-prandial blood sugar, blood urea, serum creatinine, lipid profile, glycated haemoglobin, and microalbuminuria. Ultrasonographic scanning of the carotid arteries was performed to measure the carotid IMT. For identification of cases of silent ischaemia, treadmill test (TMT) was performed. RESULTS: The study group was divided into a non-CAD group (n=40), and a CAD group (n=71). The mean carotid IMT of the group as a whole, was 0.840 +/- 0.2 mm. The mean carotid IMT was significantly higher (p<0.0001) in type 2 diabetics with CAD (both overt and silent) than in those without CAD. In diabetics with CAD, the systolic blood pressure, diastolic blood pressure and triglycerides were found to be predictors of high mean carotid IMT. On subgroup analysis of the cases with silent ischaemia, the variables affecting carotid IMT were serum creatinine, total cholesterol, microalbuminuria/proteinuria, serum triglyceride levels, and diastolic blood pressure. CONCLUSION: A high carotid IMT is a surrogate and reliable marker of higher risk of CAD amongst type 2 diabetic patients, even in those without overt CAD. The study underlines the utility of carotid IMT as a simple, non-invasive, safe, and cheap screening test for the assessment of risk/prognosis of CAD in type 2 diabetics. We have also demonstrated the usefulness of measuring IMT, as a means to detect silent CAD among type 2 diabetics.


Subject(s)
Carotid Arteries/pathology , Carotid Artery Diseases/pathology , Diabetes Mellitus, Type 2/physiopathology , Tunica Intima/pathology , Biomarkers , Carotid Arteries/diagnostic imaging , Carotid Artery Diseases/diagnosis , Carotid Artery Diseases/diagnostic imaging , Coronary Artery Disease , Exercise Test , Fasting , Female , Humans , Male , Middle Aged , Multivariate Analysis , Postprandial Period , Prognosis , Risk Assessment , Risk Factors , Time Factors , Tunica Intima/diagnostic imaging , Ultrasonography
12.
J Parasit Dis ; 42(1): 19-21, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29491553

ABSTRACT

A total of 445 faecal samples and 128 rumens of sheep collected from Slaughter house, Mhow (Madhya Pradesh) were examined for a period of 1 year from February 2011 to January 2012. Faecal sample examination based, incidence of amphistomes was found to be 23.37% from the study area. The incidence of amphistomes was significantly higher (p < 0.01) during summer (36.75%) than winter (27.74%) and monsoon (3.52%). Age-wise, non-significantly higher infection was observed in ≥1 year-old animals (23.61%) than <1 year-old animals (23.11%). Non-significantly higher rate of infection was recorded in case of females (25.63%) than that of males (19.64%). Out of 128, 49 (38.28%) rumens were found positive for amphistomes. The prevalence of Paramphistomum cervi (27.34%) was found to be significantly (p < 0.01) higher than Gastrothylax crumenifer (10.94%).

13.
J Clin Invest ; 83(5): 1774-7, 1989 May.
Article in English | MEDLINE | ID: mdl-2540223

ABSTRACT

Endothelium-derived relaxing factor has been recently identified as nitric oxide. The purpose of this study was to determine if vasodilator drugs that generate nitric oxide inhibit vascular smooth muscle mitogenesis and proliferation in culture. Three chemically dissimilar vasodilators, sodium nitroprusside, S-nitroso-N-acetylpenicillamine and isosorbide dinitrate, dose-dependently inhibited serum-induced thymidine incorporation by rat aortic smooth muscle cells. Moreover, 8-bromo-cGMP mimicked the antimitogenic effect of the nitric oxide-generating drugs. The antimitogenic effect of S-nitroso-N-acetylpenicillamine was inhibited by hemoglobin and potentiated by superoxide dismutase, supporting the view that nitric oxide was the ultimate effector. Sodium nitroprusside and S-nitroso-N-acetylpenicillamine significantly decreased the proliferation of vascular smooth muscle cells. Moreover, the inhibition of mitogenesis and proliferation was shown to be independent of cell damage, as documented by several criteria of cell viability. These results suggest that endogenous nitric oxide may function as a modulator of vascular smooth muscle cell mitogenesis and proliferation, by a cGMP-mediated mechanism.


Subject(s)
Cyclic GMP/analogs & derivatives , Growth Inhibitors/toxicity , Mitosis/drug effects , Muscle, Smooth, Vascular/drug effects , Nitric Oxide/toxicity , Vasodilator Agents/toxicity , Animals , Cells, Cultured , Cyclic GMP/toxicity , Hemoglobins/pharmacology , Isosorbide Dinitrate/toxicity , Nitroprusside/toxicity , Penicillamine/analogs & derivatives , Penicillamine/toxicity , Rats , S-Nitroso-N-Acetylpenicillamine
14.
Biochim Biophys Acta ; 925(3): 341-6, 1987 Sep 11.
Article in English | MEDLINE | ID: mdl-3113496

ABSTRACT

The unidirectional fluxes of Na+, Cl- and Ca2+ and activities of calmodulin in the intestinal microvillar core were studied in Escherichia coli heat-stable enterotoxin-treated mice. There was net secretion of Na+ and Cl- in toxin-treated animals, while in control animals there was net absorption of these ions. In both control and experimental animals, there was net absorption of Ca2+; however, the absorption was significantly higher (P less than 0.01) in experimental animals when compared to controls. In the presence of Ca2+-ionophore, there was a net secretion of Na+ and Cl- in controls, while the Ca2+-ionophore could not cause any change in the fluxes of these ions in experimental animals. The activity of calmodulin was significantly higher (P less than 0.01) in experimental animals. Verapamil, a calcium channel blocker, and trifluoperazine, a calmodulin inhibitor, reversed the effects of Ca2+-ionophore and heat-stable enterotoxin. These studies demonstrate that the toxin acts through Ca2+-calmodulin, and secretion of Na+ and Cl- in experimental animals is due to an increase in calcium absorption and an increase in calmodulin activity in the intestinal microvillar core.


Subject(s)
Bacterial Toxins/toxicity , Diarrhea/chemically induced , Enterotoxins/toxicity , Escherichia coli , Animals , Calcimycin/pharmacology , Calcium/metabolism , Calmodulin/metabolism , Chlorides/metabolism , Diarrhea/metabolism , Escherichia coli Proteins , Intestinal Absorption/drug effects , Intestinal Mucosa/drug effects , Mice , Sodium/metabolism , Trifluoperazine/pharmacology , Verapamil/pharmacology
15.
Atherosclerosis ; 122(1): 69-77, 1996 Apr 26.
Article in English | MEDLINE | ID: mdl-8724113

ABSTRACT

We compared biochemical and molecular methods for the identification of heterozygous carriers of mutations in the cystathionine beta-synthase (CBS) gene. Eleven relatives of seven unrelated patients with homocystinuria due to homozygous CBS deficiency and controls were studied with respect to total homocysteine concentrations before and after methionine loading. In addition, we determined CBS activity in cultured skin fibroblasts and tested for the presence of five known mutations by a PCR-based method in these seven patients, their relatives and controls. The results demonstrate that measurement of homocysteine after methionine loading and assay of CBS enzyme activity in cultured fibroblasts identify most but not all heterozygotes. There was significant correlation between homocysteine concentrations and CBS activities only after methionine loading (r = 0.12, 0.48, 0.48 and 0.50 at 0, 4, 6 and 8 h, respectively). Among the homozygous patients, molecular approaches identified five T833C and two G919A mutations out of 14 independent alleles, confirming the studies of others that these represent the two most prevalent mutations. In addition, we found that three of six heterozygotes with the T833 C allele had post-methionine loading homocysteine levels which overlapped with controls and of the other three, one (as well as an obligate heterozygote who did not carry any of the five mutant alleles tested) had CBS activity comparable to that of controls. These findings demonstrate that genotyping is useful as an adjunctive method for the diagnosis of the heterozygous carrier state of CBS deficiency.


Subject(s)
Biochemistry/methods , Genetic Carrier Screening/methods , Homocystinuria/genetics , Molecular Biology/methods , Adolescent , Adult , Base Sequence , Cystathionine beta-Synthase/metabolism , DNA Mutational Analysis , Female , Heterozygote , Homocysteine/urine , Homocystinuria/enzymology , Humans , Male , Methionine , Middle Aged , Molecular Probes/genetics , Molecular Sequence Data , Pyridoxine
16.
Atherosclerosis ; 154(3): 739-46, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11257277

ABSTRACT

Increased iron stores may play a role in the development of coronary heart disease (CHD) by increasing lipoprotein oxidation. Recently, mutations have been discovered in the gene (HFE) for hereditary hemochromatosis, an autosomal recessive condition of disordered iron metabolism, absorption, and storage. It is possible that people who carry HFE mutations have increased risk of CHD. We used a prospective case-cohort design (243 CHD cases and 535 non-cases) to determine whether the HFE C282Y mutation was associated with incident CHD in a population-based sample of middle-aged men and women. The frequencies of homozygosity and heterozygosity for the C282Y mutation in the ARIC study population were 0.2% (one homozygous person) and 6%, respectively. The C282Y mutation was associated with nonsignificantly increased risk of CHD (relative risk=1.60, 95% CI 0.9-2.9). After adjusting for other confounding risk factors (age, race, gender, ARIC community, smoking status, diabetes status, hypertension status, LDL cholesterol, HDL cholesterol, and triglycerides), the association became stronger (relative risk=2.70, 95% CI 1.2-6.1). However, a sensitivity analysis showed that this estimate of relative risk was somewhat unstable due to few subjects in some strata. Our prospective findings suggest that individuals carrying the HFE C282Y mutation may be at increased risk of CHD.


Subject(s)
Coronary Disease/genetics , HLA Antigens/genetics , Hemochromatosis/genetics , Histocompatibility Antigens Class I/genetics , Membrane Proteins , Mutation , Cohort Studies , Female , Gene Frequency , Genetic Predisposition to Disease , Hemochromatosis Protein , Heterozygote , Homozygote , Humans , Male , Middle Aged , Prospective Studies
17.
Neuroscience ; 57(2): 467-72, 1993 Nov.
Article in English | MEDLINE | ID: mdl-7509470

ABSTRACT

In the present study the effect of cocaine on thymidine, uridine and leucine incorporation was assessed in primary cortical glial and C6 glioma cells. Cocaine exposure for 24 h inhibited thymidine and uridine incorporation in cortical glial and C6 glioma cells. However, the effect of cocaine on uridine incorporation was less prominent compared to thymidine incorporation. High concentrations of cocaine inhibited leucine incorporation in C6 glioma cells but not in cortical glia. Cocaine exposure for four days decreased cell proliferation of cortical glial and C6 glioma cells. Cocaine-induced attenuation of macromolecular syntheses was not due to cell death since cocaine-treated cells were not stained with Trypan Blue and did not release lactate dehydrogenase into culture supernatants. Furthermore, cocaine had no effect on glutamate uptake either in cortical glia or in C6 glioma cells. These results indicate that cocaine inhibits macromolecular syntheses in glial cells. The inhibition of macromolecular syntheses in glial cells may be the mechanism involved in cocaine-induced fetal brain growth retardation.


Subject(s)
Cocaine/pharmacology , Neuroglia/metabolism , Animals , Animals, Newborn , Brain Neoplasms/metabolism , Cell Division/drug effects , Cells, Cultured , DNA/biosynthesis , Glioma/metabolism , Glutamates/metabolism , Glutamic Acid , L-Lactate Dehydrogenase/biosynthesis , Leucine/metabolism , Nerve Tissue Proteins/biosynthesis , Neuroglia/drug effects , Neuroglia/enzymology , RNA/biosynthesis , Rats , Rats, Sprague-Dawley , Thymidine/metabolism , Trypan Blue , Tumor Cells, Cultured , Uridine/metabolism
18.
Biotechniques ; 6(4): 294-6, 1988 Apr.
Article in English | MEDLINE | ID: mdl-2856235

ABSTRACT

The activity of calmodulin as an activator of cAMP phosphodiesterase was assayed. AMP was hydrolyzed by 5'-nucleotidase, and the adenosine formed was measured by both liquid scintillation counting and spectrophotometry at 265 nm. Calmodulin activities measured by the two methods were equivalent, indicating that spectrophotometric assay of calmodulin can be used in place of the isotopic method.


Subject(s)
Calmodulin/analysis , Spectrophotometry, Ultraviolet/methods , 3',5'-Cyclic-AMP Phosphodiesterases/physiology , Cyclic AMP/metabolism , Radioimmunoassay/methods
19.
FEMS Microbiol Lett ; 48(2): 155-9, 1989 Jan 15.
Article in English | MEDLINE | ID: mdl-2566554

ABSTRACT

The uptake of D-glucose, L-aspartate, L-lysine and L-proline was investigated in renal brush border membrane (BBM) vesicles prepared from control, infected or passively-immunized-infected rats. Except L-aspartate, a progressive decrease in the uptake of these nutrients in both infected and immunized-infected groups during the course of infection was observed, but the changes were less apparent in immunized-infected rats than in non-immunized ones. The uptake of L-aspartate was increased in vesicles from early stages of infection but decreased in those from later stages. Also in L-aspartate uptake, the changes were smaller in immunized animals. The uptake of nutrients was detectable earlier than were histopathological alterations of both kidneys. The observations demonstrated that uptake of D-glucose and amino acids in the kidneys is disturbed prior to appearance of histopathological lesions and thus can be used for early detection of the disease. The data also demonstrate that antipili antibodies afford partial protection against ascending pyelonephritis.


Subject(s)
Antibodies, Bacterial/administration & dosage , Fimbriae, Bacterial/immunology , Kidney/metabolism , Pyelonephritis/metabolism , Animals , Aspartic Acid/metabolism , Biological Transport, Active , Escherichia coli/immunology , Escherichia coli Infections/etiology , Escherichia coli Infections/metabolism , Escherichia coli Infections/prevention & control , Glucose/metabolism , Immunization , Lysine/metabolism , Microvilli/metabolism , Proline/metabolism , Pyelonephritis/etiology , Pyelonephritis/prevention & control , Rats
20.
FEMS Microbiol Lett ; 54(1-3): 169-73, 1990 Jan 01.
Article in English | MEDLINE | ID: mdl-2108896

ABSTRACT

The mucosal-to-serosal and serosal-to-mucosal fluxes of Na+ and Cl- were measured in control mice and mice treated with heat-stable (ST) and heat-labile (LT) enterotoxins in the presence or absence of: Ca2(+)-ionophore A23187, an activator of Ca2(+)-calmodulin; or phorbol-12-myristate-13-acetate (PMA), an activator of protein kinase C(PKC); or 1-(5-isoquinolinyl sulphonyl)-2-methyl piperazine (H-7), an inhibitor of PKC. There was net secretion of Na+ and CL- in both experimental groups in contrast to net absorption in the control group. The addition of ionophore or PMA or ionophore + PMA resulted in net secretion of Na+ and Cl- in the control group and the effect of ionophore and pMA was found to be additive. The addition of ionophore did not cause any change in electrolyte fluxes in the ST toxin treated group, however, it increased the net secretion of Na+ and Cl- in the LT toxin treated group. PMA increased the net secretion of Na+ and Cl- in the St toxin treated group, however, it did not cause any change in Na+ and Cl- fluxes in the LT toxin treated group. H-7 did not reverse the effect of ST toxin, however, it reversed the effect of LT toxin.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Bacterial Toxins/pharmacology , Enterotoxins/pharmacology , Escherichia coli Proteins , Ileum/drug effects , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine , Animals , Biological Transport, Active/drug effects , Calcimycin/pharmacology , Calcium/metabolism , Calmodulin/metabolism , Chlorides/metabolism , Escherichia coli , Ileum/metabolism , Isoquinolines/pharmacology , Mice , Piperazines/pharmacology , Protein Kinase C/metabolism , Sodium/metabolism , Tetradecanoylphorbol Acetate/pharmacology
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