970 research outputs found
Magnetic moments of spin {1/2}^+ and spin {3/2}^+ charmed baryons
The magnetic moments of spin and spin charmed baryons
have been calculated in chiral constituent quark model (CQM). The effects
of configuration mixing and quark masses have also been investigated. The
results are not only in good agreement with existing experimental data but also
show improvement over other phenomenological models.Comment: 5 pages, 2 tables. Presented at the XIII International Conference on
Hadron Spectroscopy, Florida State University, Florida, USA, November
29-December 4, 200
PHYTOCHEMICAL INVESTIGATION AND ANTIMICROBIAL PROPERTIES OF DIOSCOREA BULBIFERA TUBER
  Objective: The inhibitory properties of successive extracts from Dioscorea bulbifera (Dioscoreaceae) tubers have been evaluated for the presence of phytochemical constituents and antimicrobial efficacy against multidrug-resistant (MDR) clinical isolates was evaluated.Methods: The tuber of D. bulbifera was oven dried and extracted successively with n-hexane, chloroform, methanol, ethanol, and water. The antimicrobial potential of successive extracts against MDR isolates was studied by agar well-diffusion method. Qualitative phytochemical analysis was performed.Results: Qualitative phytochemical analysis demonstrated the presence of steroids, flavonoids, cardiac glycosides, saponins, and reducing sugars in almost all the extracts tested. Anthraquinones, phlobatanins, and tannins were not reported in any extracts tested. The in vitro antimicrobial activity of various solvents and water extracts of D. bulbifera was further investigated against ten MDR bacteria and three fungi, respectively. Aqueous and chloroform extracts were found to be more potent being capable of exerting significant inhibitory activities against the majority of the isolates such as Escherichia coli, Acinetobacter sp., Salmonella paratyphi, Klebsiella pneumoniae, and Candida albicans. The highest inhibitory activity was observed for K. pneumoniae with wide inhibition zone diameters (17 ± 0.15 mm), followed by E. coli 1(13 ± 0.11) mm, and Acinetobacter sp. (11 ± 0.12).Conclusion: Based on the present study, the extracts of D. bulbifera tubers have shown excellent activity against MDR microbial cultures tested. Further study is recommended for clinical evaluation, of the efficacy of crude extract in herbal medicine that can serve as a base for the development of novel potent drugs and phytomedicines
P53 tumour-suppressor gene mutations are mainly localised on exon 7 in human primary and metastatic prostate cancer.
Mutations in the p53 tumour-suppressor gene are among the most common genetic alterations in human cancers. In the present study we analysed the mutations in the p53 tumor-suppressor gene in 25 primary and 20 metastatic human prostate cancer specimens. DNA extracted from the paraffin-embedded sections was amplified by hot-start polymerase chain reaction, and p53 gene mutations in the conserved mid-region (exons 4-9) were examined using single-strand conformation polymorphism (SSCP) analysis and immunohistochemistry. In the present study, we used a novel hot-start PCR-SSCP technique using DNA Taq polymerase antibody, which eliminates primer-dimers and non-specific products. Because of this new technique, the results of PCR-SSCP showed very high resolution. Polymerase chain reaction products were sequenced directly for point mutations for the p53 gene. Mutations were found in 2 out of 25 primary prostate cancers (8%) and 4 out of 20 metastatic cancers (20%). Mutations were observed exclusively in exon 7 and not in exons 4, 5, 6, 8 or 9. Nuclear accumulation of p53 protein, determined by immunohistochemistry, correlated with the degree of metastasis in prostatic cancer
Magnetic moments of the low-lying , resonances within the framework of the chiral quark model
The magnetic moments of the low-lying spin-parity ,
resonances, like, for example, ,
, as well as their transition magnetic moments, are
calculated using the chiral quark model. The results found are compared with
those obtained from the nonrelativistic quark model and those of unitary chiral
theories, where some of these states are generated through the dynamics of two
hadron coupled channels and their unitarization
Experiments on initial behaviour of corone generated with electrical pulses superimposed on DC Bias
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