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21.
M M Palcic J Ripka K J Kaur M Shoreibah O Hindsgaul M Pierce 《The Journal of biological chemistry》1990,265(12):6759-6769
Baby hamster kidney (BHK) cells transformed with Rous sarcoma virus, RS-BHK cells, demonstrate a 2.5-fold increase in the activity of N-acetylglucosaminyltransferase V (GlcNAc-T V, EC 2.4.1.155), and this increase in activity appears to be specific for this enzyme. By contrast, a lectin-resistant BHK cell line selected for its ability to grow in high levels of L-phytohemagglutinin, LP3.3, is characterized by a specific decrease in its GlcNAc-T V activity. To test if these alterations in the apparent Vmax of GlcNAc-T V are due to changes in the efficiency of populations of enzymes in RS-BHK and LP3.3 cells compared to the parental BHK cells, we have compared the kinetic properties of the enzymes from these three sources. The Km constants observed for both the sugar nucleotide donor (UDP-GlcNAc) and two synthetic trisaccharide acceptors were indistinguishable. The Vmax values toward three synthetic acceptors were also determined first for the BHK GlcNAc-T V, and they varied by over 5-fold. When these values were measured for the variant and transformed cell enzymes, however, similar 5-fold differences were still observed, although the absolute values for these acceptors were all higher or lower for the RS-BHK and LP3.3 enzymes, respectively. In addition, we have synthesized a deoxygenated analog of the specific GlcNAc-T V acceptor, beta GlcNAc(1,2) alpha Man(1,6) beta ManOR, where the reactive 6'-OH group has been removed, and the resulting trisaccharide was found to be a competitive inhibitor of the enzyme. The Ki for this inhibitor was near 70 microM for the GlcNAc-T V from all three sources. These kinetic comparisons demonstrate that the enzymes from the three cell types have kinetically indistinguishable active sites. These results suggest that the differences in the apparent Vmax values among the cell types are most likely due to alterations in the number of active molecules rather than in the modulation of either their catalytic activities or specificities. 相似文献
22.
The proportion of the cortical thickness to the total diameter of the bone (cortical index) was calculated in paired clavicles obtained from 128 male and 82 female medicolegal postmortem subjects who were apparently healthy prior to their accidental death. The ages of the subjects varied from 15 to 85 years. The clavicles were cut either horizontally or parasagittally, and measurements were taken at midclavicle. From the ages of 15 to 30 years, the cortical index increased. It decreased steadily thereafter, with an initial sharp decrease in the age group 31-40 years in both sexes. After the age of 40 years, this rapid decrease in the index continued in the females, but became slow and gradual in the males. Differences between left and right sides were statistically insignificant in both sexes (P greater than 0.05). However, the sexual differences were significant (P less than 0.01) in the age groups from 41 years onwards. 相似文献
23.
B.S. Gill Y. Bhattacharyulu D. Kaur A. Singh 《International journal for parasitology》1978,8(6):467-469
Gill B.S., Bhattacharyulu Y., Kaur D. and Singh A. 1978. Chemoprophylaxis with tetracycline drugs in the immunisation of cattle against Theileria annulata infection. International Journal for Parasitology8: 467–469. Three-month-old fully susceptible cross-bred calves were immunised against tropical theileriosis by treating 2-tick or 5-tick stabilate-induced Theileria annulata infections, with 1 or 2 doses of long-acting oxytetracycline (Pfizer) at 20 mg/kg body weight injected subcutaneously, or chlortetracycline at 16 mg/kg body weight daily for 8 days given orally. The treatment began on the day of the infection. After 45 days, the recovered calves were given severe 10-tick homologous stabilate challenge.The reactions were evaluated by noting fever, degree of anaemia, severity of the swelling of the regional lymph node, rate of parasitization of lymphocytes in the lymph node, and of erythrocytes in the peripheral circulation.The untreated calves developed a severe form of the disease with typical symptoms, which killed 1 of 4 and 2 of 5 calves receiving 2-tick and 5-tick stabilates, respectively. A total of 30 treated calves reacted mildly or not at all. Both the treated and untreated, recovered calves resisted completely the challenge infection which killed 3 of 4 susceptible controls. The effect of 1 dose of long-acting oxytetracycline was equal to that of 8 daily treatments with chlortetracycline; 2 doses of the oxytetracycline suppressed almost all clinical responses at immunisation. 相似文献
24.
Kaur Jaspreet Kumar Vikas Sharma Kartik Kaur Sawinder Gat Yogesh Goyal Ankit Tanwar Beenu 《International journal of peptide research and therapeutics》2020,26(1):33-41
International Journal of Peptide Research and Therapeutics - Bioactive peptides have been reported to exhibit opioid-like activity and are termed as opioid peptides. Either these are produced... 相似文献
25.
Singh Ashutosh Singh Rahul Soloman Sarma Phulen Batra Gitika Joshi Rupa Kaur Hardeep Sharma Amit Raj Prakash Ajay Medhi Bikash 《中国病毒学》2020,35(3):290-304
The recent outbreak of coronavirus disease(COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has already affected a large population of the world. SARS-CoV-2 belongs to the same family of severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome coronavirus(MERSCoV). COVID-19 has a complex pathology involving severe acute respiratory infection, hyper-immune response, and coagulopathy. At present, there is no therapeutic drug or vaccine approved for the disease. There is an urgent need for an ideal animal model that can reflect clinical symptoms and underlying etiopathogenesis similar to COVID-19 patients which can be further used for evaluation of underlying mechanisms, potential vaccines, and therapeutic strategies. The current review provides a paramount insight into the available animal models of SARS-CoV-2, SARS-CoV, and MERS-CoV for the management of the diseases. 相似文献
26.
Karashdeep Kaur 《Biomarkers》2020,25(6):498-505
Abstract Pesticide-induced DNA damage is primarily repaired by base excision repair (BER) pathway. However, polymorphism in DNA repair genes may modulate individual’s DNA repair capacity (DRC) leading to increased genotoxicity and adverse health effects. Our first study in North-West Indian population aimed to evaluate the impact of OGG1 rs1052133 (Ser326Cys; C1245G), XRCC1 rs1799782 (Arg194Trp; C26304T) and XRCC1 rs25487 (Arg399Gln; G28152A) polymorphisms on the modulation of pesticide-induced DNA damage in a total of 450 subjects (225 pesticide-exposed agricultural workers and 225 age- and sex-matched controls). DNA damage was estimated by alkaline comet assay using silver-staining method. Genotyping was carried out by PCR-RFLP using site-specific restriction enzymes. Mann-Whitney U-test revealed elevation in DNA damage parameters (p?<?0.01) in pesticide-exposed agricultural workers than controls. Chi-square test showed significant (p?<?0.05) differences in the XRCC1 Arg194Trp (C26304T) and Arg399Gln (G28152A) genotypes among two groups. Multivariate logistic-regression analysis revealed that heterozygous genotypes of OGG1 rs1052133 (326Ser/Cys; 1245CA), XRCC1 rs1799782 (194Arg/Trp; 26304CT) and XRCC1 rs25487 (399Arg/Gln; 2815GA) were positively associated (p?<?0.05) with elevated DNA damage parameters in pesticide-exposed agricultural workers. Our results strongly indicate significant positive association of variant OGG1 and XRCC1 genotypes with reduced DRC and higher pesticide-induced DNA damage in North-West Indian agricultural workers. 相似文献
27.
28.
Sharma A. D. Kaur P. Mamik Sh. Mehta M. Sharma N. 《Russian Journal of Plant Physiology》2020,67(1):139-145
Russian Journal of Plant Physiology - Lantana camara L. is noxious weed affecting ecosystem and biodiversity worldwide. However, the biochemical basis of invasiveness and adaptation to abiotic... 相似文献
29.
Amanpreet Kaur Shivani Guleria M. Sudhakara Reddy Anil Kumar 《Physiology and Molecular Biology of Plants》2020,26(2):367-377
The genetic transformation of plants is an important biotechnological tool used for crop improvement for many decades. The present study was focussed to investigate various factors affecting genetic transformation of potato cultivar ‘Kufri Chipsona 1’. It was observed that explants pre-cultured for 2 days on MS2 medium (MS medium containing 10 µM silver nitrate, 10 µM BA, 15 µM GA3), injured with a surgical blade and co-cultivated with Agrobacterium tumefaciens strain EHA105 [O.D600 (0.6)] for 2 days results in maximum transient β-glucuronidase (GUS) expression. The addition of 100 µM acetosyringone in MS2 medium also increased rate of transient GUS expression in both the explants. Clumps of putative transgenic shoots were regenerated using the optimised culture conditions from leaf and internodal explants. The stable integration of T-DNA was established using histochemical staining for GUS and amplification of DNA fragment specific to nptII and uidA genes. Within the clumps, around 67.85% of shoots showed uniform GUS expression in all the tissues and about 32.15% shoots show intermittent GUS expression establishing chimeric nature. Uniform GUS staining of the tissue was used as initial marker of non-chimeric transgenic shoots. Quantitative expression of nptII transgene was found to be directly proportional to uniformity of GUS staining in transgenic shoots. The present investigation indicated that manipulation of culture conditions and the medium composition may help to get transgenic shoots with uniform expression of transgene in all the tissues of potato cultivar ‘Kufri Chipsona 1’. 相似文献
30.
Goyal Khushboo Kaur Kamaljit Kaur Gurjit 《Physiology and Molecular Biology of Plants》2020,26(5):899-906
Physiology and Molecular Biology of Plants - The effect of potassium nitrate on the status of fermentative and sucrose metabolizing pathways was studied in two maize (Zea mays L.) genotypes, viz.,... 相似文献