801
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Singh NB, Srivastava A, Verma VK, Kumar A, Gupta SK. Mastomys natalensis: a new animal model for Mycobacterium ulcerans research. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1984; 22:393-4. [PMID: 6510972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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802
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Srivastava A, Chopra SK, Dasgupta PR. Biochemical analysis of human seminal plasma. II. Protein, non-protein nitrogen, urea, uric acid and creatine. Andrologia 1984; 16:265-8. [PMID: 6465552 DOI: 10.1111/j.1439-0272.1984.tb00281.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Seminal levels of protein, non-protein nitrogen (NPN), urea, uric acid and creatine were determined in human males divided as normal (Group I), azoospermia (Group II), infertile (Groups III, IV and V) with different sperm numbers and vasectomized (Group VI) cases. The geometrical mean level of seminal protein of Gr. I and Gr. V were significantly greater than that of Gr. IV. No significant difference in the levels of NPN and urea between any of the groups revealed. The seminal creatine level of Gr. I was significantly higher than that of Gr. III which in its turn was greater than that of Gr. VI, which recorded a value lowest of all the groups. Mean levels of uric acid of Gr. I was significantly greater than those of other five groups, taken individually. A direct correlation between uric acid level and sperm counts is an important observation that has emerged from this study.
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803
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Sanadi DR, Pringle M, Kantham L, Hughes JB, Srivastava A. Evidence for the involvement of coupling factor B in the H+ channel of the mitochondrial H+-ATPase. Proc Natl Acad Sci U S A 1984; 81:1371-4. [PMID: 6143319 PMCID: PMC344835 DOI: 10.1073/pnas.81.5.1371] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Membrane energization by ATP has been measured in vesicles containing purified bovine heart mitochondrial H+-ATPase (ATP synthase) with the voltage-sensitive dye oxonol VI. The dithiol chelator, Cd2+, and the thiol oxidant, copper o-phenanthroline, produced discharge of the membrane potential when added at the steady state and inhibited its establishment when added prior to energization by ATP. These effects, which were reversed by dithiothreitol, were not accompanied by an increase in the nonspecific H+ permeability of the membrane. Passive H+ conduction in proteoliposomes containing F0 (hydrophobic segment of ATP synthase) was assayed by the quenching of 9-aminoacridine fluorescence after establishing a K+ diffusion potential. This conductance was blocked by Cd2+, an inhibitor of coupling factor B (FB). Labeling of F0 with 115Cd2+ at the concentrations that inhibited the F0 conductance followed by gel electrophoresis yielded a single radioactive band with a molecular weight corresponding to FB, the presence of which in the F0 preparation was confirmed by immunoblot staining. The data offer strong evidence that FB is an essential component of the H+ channel of F0, because H+ conduction through the channel is inhibited by chemical modification of FB.
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804
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Muzyczka N, Samulski RJ, Hermonat P, Srivastava A, Berns KI. The genetics of adeno-associated virus. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1984; 179:151-61. [PMID: 6098150 DOI: 10.1007/978-1-4684-8730-5_15] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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805
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Srivastava A, Chowdhury AR, Setty BS. Zinc content in the epididymis, vas deferens, prostate, and seminal vesicles of juvenile rhesus monkey (Macaca mulatta): effect of androgen and estrogen. Prostate 1984; 5:153-8. [PMID: 6709519 DOI: 10.1002/pros.2990050205] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The zinc content in the three segments of the epididymis (caput, corpus, and cauda), vas deferens, seminal vesicles, and prostate of juvenile monkeys was determined by atomic absorption spectrophotometry. Zinc content (micrograms/gm wet weight) was found to be maximum (328) in the vas deferens; in the other organs it measured in the following order: caput 191, corpus 238, cauda 193, prostate 133 and seminal vesicles 85. In order to investigate the endocrine control of the zinc in these organs, two groups of animals were treated with testosterone propionate (2 mg) or estradiol dipropionate (10 micrograms) once daily for 30 days. In response to androgen, a rise in both concentration and content of zinc was evident only in the prostate. The results further suggested that the prostatic zinc may be under dual hormonal control, but in the epididymis and vas deferens it may be under the influence of estrogen. It is concluded that the hormonal effects on zinc content and growth stimulation in accessory sex organs are quite separate and may be under different hormonal control.
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806
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Srivastava A, Chopra SK, Dasgupta PR. Biochemical analysis of human seminal plasma. I. Fructose, ascorbate, cholesterol, adenosine triphosphatase and lactic dehydrogenase. Andrologia 1983; 15:431-5. [PMID: 6228169 DOI: 10.1111/j.1439-0272.1983.tb00164.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Seminal levels of fructose, ascorbate, cholesterol, adenosine triphosphatase (ATPase) and lactate dehydrogenase (LDH) were estimated in human males divided into normal (Group I), azoospermic (Group II), infertile (Groups III, IV and V with different sperm numbers) and vasectomized (Group VI) cases. The fructose level of the normal subjects (Gr. I) recorded the lowest geometric mean value and that of the azoospermic patients being the highest; other groups registered intermediate values. A significant difference was evident in the level of ascorbate between normal (Gr. I) and azoospermic (Gr. II) conditions, the level being higher in the normal group. The seminal ATPase activity of different groups varied inversely with the number of sperms, the mean value of the normal (Gr.I) being the lowest. The results suggest that determination of seminal ATPase and ascorbate levels is likely to yield some useful information about the semen quality.
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807
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Schachinger L, Srivastava A, Schippel C, Klöter H. Effect of irradiated dib-cAMP on the tonic and phasic activity of human myometrium. STRAHLENTHERAPIE 1983; 159:358-65. [PMID: 6308855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cyclic AMP, used as dibutyryl derivative for better permeability, has a relaxing effect on smooth muscle preparations from human uterine tissue (surgical material). The observed decrease of tonus and frequency depends on the concentration applied, shown in the range between 50 and 300 microM. cAMP looses its physiological activity by irradiation in vitro; in addition an inhibitory action of the irradiation products on uterine tissue could be proved. From the data of the Lineweaver-Burk plots, showing the competition between non-irradiated and irradiated cAMP, a ten-to twentyfold higher affinity of the irradiation products to the receptor compared to that of this transmitter could be calculated. The results show that preparations of human origin with beta-receptors behave similarly to animal tissues with beta-receptors. They are further discussed with respect to a better understanding of dose-response curves for chemical and physiological inactivation.
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808
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Samulski RJ, Srivastava A, Berns KI, Muzyczka N. Rescue of adeno-associated virus from recombinant plasmids: gene correction within the terminal repeats of AAV. Cell 1983; 33:135-43. [PMID: 6088052 DOI: 10.1016/0092-8674(83)90342-2] [Citation(s) in RCA: 242] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We have isolated three types of pBR322-AAV recombinant plasmids that contain deletions within the 145 bp AAV terminal repeats. When the plasmids were transfected into human cells, mutants that contained deletions within the left (type I) or right (type II) terminal repeat were viable. Of four mutants examined that contained deletions in both termini (type III), only one was viable. All of the viable mutants produced AAV virions that contained wild-type AAV DNA. Furthermore, the viable type III deletion could be converted to a nonviable mutant by deleting all copies of an 11 bp sequence from its termini. We conclude that there is an efficient mechanism for correcting deletions within the AAV termini. A model that could account for these observations is also discussed.
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809
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Gupta SC, Kumar S, Srivastava A. Urethral myiasis. TROPICAL AND GEOGRAPHICAL MEDICINE 1983; 35:73-4. [PMID: 6612774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A case of urethral myiasis is reported. The authors are not aware of any such reference in the literature.
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810
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Srivastava A, Lusby EW, Berns KI. Nucleotide sequence and organization of the adeno-associated virus 2 genome. J Virol 1983; 45:555-64. [PMID: 6300419 PMCID: PMC256449 DOI: 10.1128/jvi.45.2.555-564.1983] [Citation(s) in RCA: 530] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The complete nucleotide sequence of the adeno-associated virus 2 genome was determined. The single-stranded genome is 4,675 nucleotides in length and contains inverted terminal repeats of 145 nucleotides, the first 125 nucleotides of which form a palindromic sequence. Within the inverted terminal repetitions, there are two distinct sequences representing an inversion of 43 nucleotides that can exist on either terminus. The 5' and 3' termini of three major mRNA transcripts, which are present in both spliced and unspliced forms, were also mapped on the viral genome. Potential initiation and termination codons for efficient protein synthesis were identified, and genome segments were assigned that code for three major viral capsid proteins and, possibly, some as-yet-unidentified, nonstructural viral proteins.
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811
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Srivastava A, Chowdhury AR, Setty BS. Zinc content of maturing spermatozoa in oestrogen treated rats. INTERNATIONAL JOURNAL OF ANDROLOGY 1983; 6:103-8. [PMID: 6840876 DOI: 10.1111/j.1365-2605.1983.tb00327.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Zinc content of spermatozoa collected from the caput and cauda portions of the rat epididymis was determined by atomic absorption spectroscopy. The results showed about 60% reduction in the spermatozoal zinc content by the time they reach the cauda epididymis. This reduction was inhibited in rats receiving micro dose oestrogen which induced 'functional' sterility. It appears that the fall in zinc content of spermatozoa during their transport in the epididymis is related to sperm maturation and that oestrogen treatment interferes with this reduction in sperm zinc content.
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812
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Gupta V, Mudgil A, Srivastava A, Rathi AK. Serum gamma glutamyl transferase in Indian childhood cirrhosis. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1983; 80:6-7. [PMID: 6134776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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813
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Abstract
This paper is based on a radiographic study of 300 normal individuals from 18 to 34 years of age comprising 207 males and 93 females. A lateral radiograph of the cervical spine with a focal-film distance of 6 ft was obtained of each subject to measure the sagittal diameter of the cervical spinal canal. The mean sagittal diamter ranged from 21.43 mm at C1 to 16.42 mm at C7 in males and from 20.13 mm at C1 to 15.54 mm C7 in females. This diameter decreased from C1 down to C4 or C5 where there was a gradual but marginal increase to C6. This diameter was smallest at C7. In general the sagittal diameters In females were about 1 mm less than in males at all vertebral levels. The smallest sagittal diamter from C3 to C7 in both sexes was 13 mm. The largest sagittal diameter varied from 20.5 to 28 mm in males and 18.5 to 26 mm in females. The mean sagittal diameter showed some relationship to height in males. No significant difference was observed in relation to weight. The posterior component of the sagittal diameter was smaller in females than in males due to a difference in development of the laminae.
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814
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Sethi BB, Trivedi JK, Srivastava A, Yadav S. Indigenous therapy in practice of psychiatry in India. Indian J Psychiatry 1982; 24:230-6. [PMID: 21965917 PMCID: PMC3012811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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815
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Srivastava A, Dhar JD, Chowdhury AR, Chandra H, Setty BS. Zinc in the epididymal and vasal spermatozoa of rhesus monkey (Macaca mulatta). ARCHIVES OF ANDROLOGY 1982; 8:117-20. [PMID: 7073389 DOI: 10.3109/01485018208987027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Zinc level in maturing spermatozoa collected from caput, corpus, and cauda regions of the epididymis and vas deferens of rhesus monkey was measured. Spermatozoa collected from the caput epididymis have the highest concentration of zinc (36 micrograms/10(8) spermatozoa). There was a marked reduction in the zinc content of corpus spermatozoa and a further decrease in the spermatozoa of cauda epididymis. Thus the zinc content of spermatozoa gradually decreases as they migrate from the caput to cauda epididymis. There was a significant increase in the zinc content of vasal spermatozoa as compared to those collected from the cauda region of epididymis.
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816
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Srivastava A. Determination of sulphur functions with iodoso-compounds. Talanta 1982; 29:31-5. [PMID: 18963072 DOI: 10.1016/0039-9140(82)80131-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/1980] [Revised: 06/01/1981] [Accepted: 06/09/1981] [Indexed: 11/17/2022]
Abstract
Iodoso derivatives, e.g., m- and p-chlorophenyl, m- and p-methylphenyl and p-nitrophenyl-iodosoacetates and o-diacetoxyiodobenzoate, have been thoroughly investigated as oxidants and are proposed as analytical reagents for the determination of thiols, thioureas, isothiocyanates, organic sulphides, disulphides, xanthates, dithiocarbamates, amines and alcohols in aqueous and non-aqueous (acetic acid, acetonitrile, dimethylformamide) media. The error of the determination of thiols is 0.2% thioureas 0.5%, organic sulphides and disulphides 0.4%, isothiocyanates 0.4%, dithiocarbamates 0.4%, and xanthates 0.5%. All the methods are precise to 0.2-0.5%. It is also shown that the properties of the o-derivatives differ markedly from those of the m- and p-derivatives. The o-derivatives contain a 1-substituted 1,2-benzoiodoxilin-3-one ring system. The stability of this system is apparently associated with the size of the five-membered ring; other compounds in which iodine is apparently part of larger rings are less stable. o-Diacetoxyiodobenzoate appears to be the best analytical reagent of the iodoso series. The m- and p-iodosobenzoates are found unsuitable for quantitative oxidation of cysteine.
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817
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Singh NB, Srivastava A, Mathur IS, Gupta HP, Gupta SK. Effect of rifampicin treatment of Myobacterium avium infection in carbon tetrachloride treated rabbits. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1981; 19:201-2. [PMID: 7287076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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818
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Sethi BB, Sharma M, Srivastava A. Social interaction and neuroses (the family and the primary group): a pilot study. Indian J Psychiatry 1981; 23:33-9. [PMID: 22058512 PMCID: PMC3013182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The present work examines the social interaction with the primary group of 30 neurotic patients and 30 matched controls. A comparison of the degree of family jointness in the two groups was also done keeping in view the nature of Indian family system and to find out the association, if any, it bears to social interaction. Evaluation instruments were Social Interaction Schedule (Henderson et al., 1978) and Khatri's Scale to Measure Jointness of Families in India (1970). The findings indicate that neurotic patients do not have a deficient primary group, as far as the numerical size and the duration and type of interaction is concerned. However, the patients appear to be less active than controls in making contacts with members of their primary group outside their household. Further, our group of patients perceived their personal lives to be deficient in some respects. Patients and controls did not differ with regard to the degree of family jointness as measured on Khatri's Scale.
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819
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Modak MJ, Srivastava A, Gillerman E. Observations on the phosphonoformic acid inhibition of RNA dependent DNA polymerases. Biochem Biophys Res Commun 1980; 96:931-8. [PMID: 6158948 DOI: 10.1016/0006-291x(80)91444-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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820
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Srivastava A, Modak MJ. Biochemistry of terminal deoxynucleotidyltransferase: identification, characterization, requirements, and active-site involvement in the catalysis of associated pyrophosphate exchange and pyrophosphorolytic activity. Biochemistry 1980; 19:3270-5. [PMID: 6250559 DOI: 10.1021/bi00555a026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Terminal deoxynucleotidyltransferase (TdT) has been found to catalyze both pyrophosphate exchange and pyrophosphorolysis reactions. Both reactions are strongly inhibited by antiserum to TdT. The reactions require the presence of a divalent cation, a single- or double-stranded oligomeric or polymeric DNA or RNA, and deoxyribonucleoside triphosphates (for PPi exchange only). Of the three divalent cations tested, Mg2+ and Co2+ are equally effective, while Mn2+ neither is used for catalysis nor inhibits the Mg2+-catalyzed reactions. Ribonucleoside triphosphates have been found to support the PPi exchange reaction to a minor extent and have no inhibitory effect on the catalysis mediated by dNTPs. Inhibition studies, using SH group inhibitors, Zn chelator, and a substrate binding site specific reagent, revealed that PPi exchange and pyrophosphorolysis reactions may be distinguished by differences in their sensitivity to inhibition by various reagents. While the PPi exchange reaction is strongly inhibited by sulfhydryl reagents, o-phenanthroline, and pyridoxal phosphate, the pyrophosphorolysis reaction is insensitive to these reagents. In addition, the pyrophosphorolysis reaction is also found not to require a free 3'-OH terminus of a primer. This difference in the susceptibility of the two reactions indicates that discrete active-site structures exist in TdT which catalyze PPi exchange and pyrophosphorolysis reactions.
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821
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Singh NB, Mathur IS, Gupta HP, Srivastava A, Gupta SK. Increased susceptibility of rabbits to intravenous challenge with Mycobacterium avium after mild hepatitis produced by carbon tetrachloride. J Med Microbiol 1980; 13:319-22. [PMID: 7381919 DOI: 10.1099/00222615-13-2-319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A mild grade of liver damage in rabbits was produced by giving 23 subcutaneous injections of carbon tetrachloride (CCl4). The CCl4-treated rabbits and untreated controls were subsequently challenged with the mildly virulent strain of Mycobacterium avium Kirschberg (TMC 801). In two successive experiments it has been found that liver damage increased the susceptibility of rabbits to infection with this organism.
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822
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Srivastava A, Modak MJ. Enzymatic activities associated with avian and murine retroviral DNA polymerases. Catalysis of and active site involvement in pyrophosphate exchange and pyrophosphorolysis reactions. J Biol Chem 1980; 255:2000-4. [PMID: 6153389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Reverse transcriptase isolated from avian myeloblastosis virus (AMV) and Rauscher murine leukemia virus (RLV) were examined for their ability to catalyze polymerization, ribonuclease H, pyrophosphate exchange, and pyrophosphorolysis reactions. A detailed characterization and a study of requirements for the expression of pyrophosphate exchange and pyrophosphorolysis reactions indicated that a variety of RNA and DNA template-primers supported these catalytic reactions. Furthermore, hydrogen bonding of template to primer was essential, although RNA:RNA template-primers, e.g. poly(rA) . (rU)9 or 70 S RNA . tRNA complex, were not utilized for these reactions. AMV enzyme required Mg2+, and RLV enzyme Mn2+, as the preferred divalent metal ion for the expression of these activities. Response of various catalytic reactions to site-specific inhibitors revealed that polymerization and pyrophosphate exchange reactions were susceptible to reagents that affected either the substrate or the template binding site, intrinsic zinc, or sulfhydryl groups. RNase H and pyrophosphorolysis activities, on the other hand, exhibited susceptibility only to the template site-specific reagent. We, therefore, conclude that RNase H and pyrophosphorolysis reactions are catalyzed through the template binding site while polymerization and pyrophosphate exchange reactions require additional participation of the substrate binding site, as well as that of intrinsic zinc and the presence of reactive sulfhydryl groups.
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823
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Srivastava A, Modak M. Enzymatic activities associated with avian and murine retroviral DNA polymerases. Catalysis of and active site involvement in pyrophosphate exchange and pyrophosphorolysis reactions. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)85982-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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824
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Srivastava A, Modak MJ. Phenylglyoxal as a template site-specific reagent for DNA and RNA polymerases. Selective inhibition of initiation. J Biol Chem 1980; 255:917-21. [PMID: 6985908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Phenylglyoxal, an arginine-specific reagent, strongly inhibits DNA polymerases isolated from eukaryotic, prokaryotic, and RNA tumor viral sources as well as Escherichia coli RNA polymerase. The inhibitory action of phenylglyoxal appears to be due to interference with the template binding function of these enzymes and implies the presence of an arginine residue at the template binding site of these enzymes from diverse sources and suggests that template dependent DNA, and perhaps RNA polymerases, may be mechanistically similar with respect to their template binding function. In contrast, the activity of terminal deoxynucleotidyl-transferase, a template-independent DNA polymerase isolated from calf thymus, is not inhibited by phenylglyoxal. A detailed analysis of the inhibitory process carried out using avian myeloblastosis virus (AMV) DNA polymerase as a test enzyme revealed that inclusion of template-primer during the preincubation with phenylglyoxal, but not substrate triphosphates or primer alone, protects the enzyme against phenylglyoxal inactivation. Furthermore, phenylglyoxal does not appear to inhibit the elongation of initiated DNA strands, but blocks the reinitiation of DNA synthesis.
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825
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Srivastava A, Modak MJ. Reverse transcriptase-associated RNase H. Part IV. Pyrophosphate does not inhibit RNase H activity of AMV DNA polymerase. Biochem Biophys Res Commun 1979; 91:892-9. [PMID: 93479 DOI: 10.1016/0006-291x(79)91963-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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