151
|
Rahman R, Lindsley DL. Male-sterilizing interactions between duplications and deficiencies for proximal X-chromosome material in Drosophila melanogaster. Genetics 1981; 99:49-64. [PMID: 6804302 PMCID: PMC1214491 DOI: 10.1093/genetics/99.1.49] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The genetic limits of sixty-four deficiencies in the vicinity of the euchromatic-heterochromatic junction of the X chromosome were mapped with respect to a number of proximal recessive lethal mutations. They were also tested for male fertility in combination with three Y chromosomes carrying different amounts of proximal X-chromosome-derived material (BSYy+, y+Ymal126 and y+Ymal+). All deficiencies that did not include the locus of bb and a few that did were male-fertile in all male-viable Df(1)/Dp(1;Y) combinations. Nineteen bb deficiencies fell into six different classes by virtue of their male-fertility phenotypes when combined with the duplicated Y chromosomes. The six categories of deficiencies are consistent with a formalism that invokes three factors or regions at the base of the X, one distal and two proximal to bb, which bind a substance critical for precocious inactivation of the X chromosome in the primary spermatocyte. Free duplications carrying these regions or factors compete for the substance in such a way that, in the presence of such duplications, proximally deficient X chromosomes are unable to command sufficient substance for proper control of X-chromosome gene activity preparatory to spermatogenesis. We conclude that there is no single factor at the base of the X that is required for the fertility of males whose genotype is otherwise normal.
Collapse
|
152
|
Sarngadharan MG, Kalyanaraman VS, Rahman R, Gallo RC. Simple affinity procedure for the purification of mammalian viral reverse transcriptases. J Virol 1980; 35:555-9. [PMID: 6160261 PMCID: PMC288842 DOI: 10.1128/jvi.35.2.555-559.1980] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Polyguanylic acid was found to be a potent inhibitor of RNase H associated with mammalian viral reverse transcriptase, indicating a strong interaction between polyguanylic acid and the reverse transcriptase protein. Based on this observation, we have developed three simple procedures for the purification of mammalian viral reverse transcriptases. In the first procedure, a nucleic acid-free extract of Rauscher murine leukemia virus was applied to a column of phosphocellulose and the reverse transcriptase was eluted by a low concentration (50 microM) of polyguanylic acid. Polyadenylic acid and polyuridylic acid could not replace polyguanylic acid for the elution. In the second procedure, a polyuridylic acid-Sepharose column was substituted for phosphocellulose, and the elution was again achieved by polyguanylic acid. In the third affinity procedure, the reverse transcriptase in a nucleic acid-free viral extract was incubated in the cold with 50 microM polyguanylic acid and the complex was adsorbed onto a DEAE-cellulose column. After washing to remove uncomplexed and weakly complexed proteins, the reverse transcriptase was eluted in a concentrated form at 0.3 M NaCl with a recovery of greater than 70%. by polyacrylamide gel analysis in the presence of sodium dodecyl sulfate, the enzyme appeared to be nearly pure.
Collapse
|
153
|
Rahman R, Safe S, Taylor A. Sporidesmins. Part 17. Isolation of sporidesmin H and sporidesmin J. ACTA ACUST UNITED AC 1978. [DOI: 10.1039/p19780001476] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
154
|
Charman HP, Rahman R, White MH, Kim N, Gilden RV. Radioimmunoassay for the major structural protein of Mason-Pfizer monkey virus: Attempts to detect the presence of antigen or antibody in humans. Int J Cancer 1977; 19:498-504. [PMID: 403148 DOI: 10.1002/ijc.2910190410] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The 25,000 dalton protein of Mason-Pfizer monkey virus (MPMV) was isolated by gel filtration chromatography. In agreement with results from other laboratories, antisera to type-C and the non-type-C bovine leukemia and equine infectious anemia viruses did not precipitate 125I-labelled MPMV p25. In addition, these viruses did not cross-react in a competition radioimmunoassay for MPMV p25. Twenty-one human tissues (15 breast carcinomas, 2 normal breasts, 3 acute myelogenous leukemias and 1 sarcoma) were fractionated by detergent solubilization, ammonium sulfate precipitation, and DE-52 anion exchange chromatography. These methods were shown to be highly effective for purification of MPMV p25. Under assay conditions which minimized incubation damage to the 125I-MPMV p25, all tissues failed to react in the competition radioimmunoassay (RIAT). Two hundred and two human sera or plasma specimens, including those from patients with breast cancer and 33 age-matched controls, from 50 patients with hematologic malignancies, from 12 patients with amyotrophic lateral sclerosis, and from 14 patients with systemic lupus erythematosis, were examined for antibodies to MPMV p25. With the exception of two multiple myeloma plasma which produced artifactual false positive reactions based on hypergammaglobulinemia, a known complication of salt precipitation radioimmunoassays, the remainder of the specimens were negative for evidence of MPMV p25 antibodies.
Collapse
|
155
|
Abstract
Further examination of the pithomycolide fraction of extracts of cultures of Pithomyceschartarum has resulted in the isolation of a new depsipeptide, for which the structure cyclo(L-N-methylalanyl-L-valyl-D-3-oxy-3-phenylpropionyl-D-3-oxy-3-phenylpropionyl-L-2-oxy-3-methylbutyryl) is proposed.
Collapse
|
156
|
Chapman HP, White MH, Rahman R, Gilden RV. Species and interspecies radioimmunoassays for rat type C virus p30: interviral comparisons and assay of human tumor extracts. J Virol 1976; 17:51-9. [PMID: 54444 PMCID: PMC515387 DOI: 10.1128/jvi.17.1.51-59.1976] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The major internal protein, p30, of rat type C virus (RaLV) was purified and utilized to establish intra- and interspecies radioimmunoassays. Three rat viruses were compared in homologous and heterologous intraspecies assays with no evidence of type specificity. The only heterologous viruses to give inhibition in these species assays were the feline (FeLV) and hamster (HaLV) type C viruses; these reactions were incomplete and required high virus concentrations. An interspecies assay using a goat antiserum prepared after sequentially immunizing with FeLV, RD 114, and woolly monkey virus p30's and labeled RaLV p30 was inhibited by all mammalian type C viruses, although preferentially by RaLV, FeLV, and HaLV. Thus, as in a previously reported assay developed with HaLV p30, rat, hamster, and cat p30's seem more closely related to each other than to mouse type C virus p30. High levels of specific antigen were found in all cell lines producing rat virus, whereas embryonic tissues from several rat strains and cell lines considered virus-free based on other tests were negative for p30. Rats bearing tumors containing Moloney murine sarcoma virus (RaLV) did not contain free circulating antibody to RaLV p30. Fifty-one human tumor extracts (including two tumor cell lines) were tested for activity in the RaLV species and 47 in the interspecies assays after Sephadex gel filtration and pooling of material in the 15,000- to 40,000-molecular-weight range. At a sensitivity level of 7 ng/ml (0.7 ng/assay) in the interspecies assay, all human tissues, with one exception, were negative. The one positive result is considered nonspecific based on proteolysis of the labeled antigen. Input tissue protein of the purified tumor extracts averaged 1.9 mg/ml with a range of less than 0.025 to 22 mg/ml. Tissues from NIH Swiss mice processed in the same manner were positive in the interspecies assay but negative in the intraspecies RaLV assay.
Collapse
|
157
|
Aly R, Maibach HI, Rahman R, Shinefield HR, Mandel AD. Correlation of human in vivo and in vitro cutaneous antimicrobial factors. J Infect Dis 1975; 131:579-83. [PMID: 805186 DOI: 10.1093/infdis/131.5.579] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
the presence of antimicrobial substances on human skin was investigated. Staphyloccus aureus (10-4 colony-forming units) was applied on the forearm of 50 subjects and covered with a semiocclusive device for 24 hr. In 54% of the subjects the organisms persisted, and in 34% S. aureus was inhibited on the skin. Subjects with persistent S. aureus also had persistent Candida albicans, and vice persa. This correlation was not noted with Streptococcus pyogenes. Skin lipids from the two groups of subjects were extracted with acetone and assayed against S. aureus, S. pyogenes, and C. albicans. The percentage of S. aureus or C. albicans recovered was higher (79% and 55%, respectively) in subjects with persistent microrgamisms on their skin than in those without (47% and 28%, respectively). Subjects with persistent S. aureus and C. albicans had higher counts of normal flora (average, 9.2 times 10-3) than those on whose skin these organisms did not persist (average, 7.4 times 10-2). Coagulase-negative Staphylococcus and Micrococcus were found in higher proportions in subjects with persistent test organisms than in those without. Subjects with lower counts of their normal flora had a higher proportion of diphtheroids (34%) than the high-count group (12%).
Collapse
|
158
|
Florence AT, Rahman R. The interaction of some oral contraceptive steroids with lipid monolayers and with Erythrocytes. J Pharm Pharmacol 1972; 24:942-9. [PMID: 4146525 DOI: 10.1111/j.2042-7158.1972.tb08924.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Abstract
Some steroids used in oral contraceptive combinations have been found to interact with cholesterol and lecithin spread as monolayers on water and to protect erythrocytes against haemolysis. No simple relation between steroid structure and these interactions was found, although in general the more water-soluble members of a group of structurally related compounds interacted to a lesser extent. No distinction could be observed in the behaviour of progestogens and oestrogens in the systems studied. It is suggested in the light of the evidence presented here and from data in the literature that these steroids may adsorb at lipid surfaces and may penetrate lipid membranes. This gives substance to the hypothesis that some steroids adsorb at platelet surfaces and alter the surface properties or the permeability of the platelet membrane sufficiently to cause increased platelet aggregation.
Collapse
|
159
|
Florence AT, Rahman R. The effect of some oral contraceptive steroids on platelet electrophoretic mobility in vitro. J Pharm Pharmacol 1972; 24:983-5. [PMID: 4146533 DOI: 10.1111/j.2042-7158.1972.tb08932.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
160
|
Francis E, Rahman R, Safe S, Taylor A. Sporidesmins. Part XII. Isolation and structure of sporidesmin G, a naturally-occurring 3,6-epitetrathiopiperazine-2,5-dione. ACTA ACUST UNITED AC 1972. [DOI: 10.1039/p19720000470] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
161
|
Rahman R, Safe S, Taylor A. Separation of polythiadioxopiperazine antibiotics by thin-layer chromatography. J Chromatogr A 1971; 53:592-4. [PMID: 5542457 DOI: 10.1016/s0021-9673(01)98522-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
162
|
Rahman R, Sharpless KB, Spencer TA, Clayton RB. Removal of the 4,4-dimethyl carbons in the enzymic conversion of lanosterol to cholesterol. Initial loss of the 4-alpha-methyl group. J Biol Chem 1970; 245:2667-71. [PMID: 5445804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
|
163
|
Millar JH, Rahman R, Vas CJ, Noronha MJ, Liversedge LA, Swinburn WR. Effect of withdrawal of corticotrophin in patients on long-term treatment for multiple sclerosis. Lancet 1970; 1:700-1. [PMID: 4190999 DOI: 10.1016/s0140-6736(70)90928-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
164
|
|
165
|
Rahman R, Safe S, Taylor A. Sporidesmins. Part IX. Isolation and structure of sporidesmin E. ACTA ACUST UNITED AC 1969. [DOI: 10.1039/j39690001665] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
166
|
Jamieson WD, Rahman R, Taylor A. Sporidesmins. Part VIII. Isolation and structure of sporidesmin-D and sporidesmin-F. ACTA ACUST UNITED AC 1969. [DOI: 10.1039/j39690001564] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
167
|
Abstract
Although there have been various studies of the treatment of schizophrenia and articles on it are numerous, hardly any work has been done on the subject in Pakistan.
Collapse
|
168
|
Brewer D, Hannah DE, Rahman R, Taylor A. The growth of Bacillus subtilis in media containing chetomin, sporidesmin, and gliotoxin. Can J Microbiol 1967; 13:1451-60. [PMID: 4965004 DOI: 10.1139/m67-193] [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: 01/13/2023]
Abstract
Sporidesmin, gliotoxin, and chetomin increase the lag phase of growth of Bacillus subtilis. By daily subculture of the organism in media that contained one of the antibiotics in sufficient concentration to increase the lag phase of growth by 300%, organisms were obtained whose lag phase of growth was the same as that of the parent strain (HLX 373). Repetition of this process has made it possible to obtain cultures which have a lag phase of growth of 300 ± 20 min in the presence of chetomin (0.15 μg/ml), gliotoxin (3.0 μg/ml), or sporidesmin (30 μg/ml). The culture which could grow in the presence of gliotoxin lost this ability on subcultivation in the absence of the antibiotic. Sufficient cross resistance was shown to indicate the possibility that these three antibiotics had a similar mode of action.
Collapse
|
169
|
Frings CS, Rahman R, Jones JD. Automated method for the determination of serum inorganic phosphorus. Comparison with manual procedure. Clin Chim Acta 1966; 14:563-5. [PMID: 5971893 DOI: 10.1016/0009-8981(66)90049-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|