76
|
Rahman MS, Han JC, Park J, Lee JH, Eo SK, Chae JS. Prevalence of brucellosis and its association with reproductive problems in cows in Bangladesh. Vet Rec 2006; 159:180-2. [PMID: 16891427 DOI: 10.1136/vr.159.6.180] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
77
|
Baek BK, Lee BO, Hur J, Rahman MS, Lee SI, Kakoma I. Evaluation of the Sprague-Dawley rat as a model for vertical transmission of Brucella abortus. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 2005; 69:305-8. [PMID: 16479730 PMCID: PMC1250244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Vertical transmission of Brucella abortus in Sprague-Dawley (SD) rats was verified with microbiologic, serologic, and polymerase chain reaction (PCR) methods. The 38 initially Brucella-free SD rats, weighing 200 to 250 g, were injected subcutaneously with 50 microL of a suspension containing 1 x 10(9) colony-forming units (cfu) of B. abortus biotype 1 Korean isolate. The rats were allowed to mate with uninfected SD rats. The isolate was detected by culture and by AMOS (abortus, melitensis, ovis, suis) PCR in testis tissue of infected male rats and splenic tissue of infected female rats. By 7 d after inoculation, the results of both the rose bengal test (RBT) and the plate agglutination test (PAT) were positive for antibody against B. abortus; the reciprocal antibody titre ranged from 200 to 400 in the 1-mo-old offspring and 800 in their dams. The infected rats directly transmitted Brucella to their breeding partners and offspring. Fetuses of infected dams were found to be infected at 20 d of gestation. These data are discussed in relation to a model for epizootic and zoonotic cases possibly involving wild animals. Additional rigorous experiments are warranted to explore the value of this model in developing measures to prevent congenital brucellosis.
Collapse
|
78
|
Rahman MS, Yang J, Shan LY, Unruh H, Yang X, Halayko AJ, Gounni AS. IL-17R activation of human airway smooth muscle cells induces CXCL-8 production via a transcriptional-dependent mechanism. Clin Immunol 2005; 115:268-76. [PMID: 15893694 DOI: 10.1016/j.clim.2005.01.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2004] [Revised: 01/25/2005] [Accepted: 01/31/2005] [Indexed: 11/22/2022]
Abstract
Airway neutrophilia has been recognized as a predominant feature of acute lung disorders. While it has been shown that IL-17 induces expression of the CXC chemokines in the airways leading to neutrophil recruitment, the IL-17R expression in human ASM cells and the molecular mechanism by which IL-17 mediates neutrophilic chemo-attractant CXCL-8 (IL-8) production have not been determined. Our study showed that ASM cells express steady state IL-17R protein, mRNA and surface-bound receptor. Interestingly, airway sections from COPD patients revealed IL-17R-positive immunostaining within ASM bundles. IL-17 was capable of stimulating CXCL-8 protein release from ASM cells which was significantly decreased by neutralizing anti-IL-17 mAb. Furthermore, IL-17 induction of CXCL-8 mRNA and protein release from ASM cells was abrogated by transcriptional inhibitor actinomycin D. CXCL-8 promoter reporter analysis using wild type and site specific mutant constructs demonstrated a key role for AP1 and NF-kappaB binding sites in IL-17-induced CXCL-8 expression. These data demonstrate that IL-17 mediates CXCL-8 expression in ASM cells via a transcriptional mechanism depending on NF-kappaB and AP-1 pathways. Together, our findings suggest that ASM cells play an important role in airway neutrophilia.
Collapse
|
79
|
Mannan MA, Rahman MS, Siddiqui NI. Obesity management in patients with type 2 diabetes mellitus. Mymensingh Med J 2004; 13:95-9. [PMID: 14747797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Obesity infrequently associated with type 2 diabetes mellitus and may cause insulin resistance, hypertension and other complications of obesity. So obesity management in Type 2 diabetes mellitus is essential. Prevention is a logical first step in the management of the obese Type 2 diabetic patient, such programs have had little long-term success. Diet, exercise and behavioral modification still form the cornerstones of treatment and relatively small weight loss results in improvement of all major obesity related co-morbidity's, including Type 2 diabetes. The obese diabetic patient faces extra impediments to weight loss, including the adverse effects of diabetic medication, poor glycaemic control and diabetes related complications. New drugs may offer some additional help, in general by providing the benefit associated with the weight loss as such, Bariatric surgery can produce major long-term weight loss in the severely obese subjects.
Collapse
|
80
|
Baek BK, Lim CW, Rahman MS, Kim CH, Oluoch A, Kakoma I. Brucella abortus infection in indigenous Korean dogs. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 2003; 67:312-4. [PMID: 14620870 PMCID: PMC280718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Three dogs reared on a dairy farm with a high incidence for Brucella abortus were serologically positive for B. abortus and no other Brucella spp. The identity of the organism was confirmed to be B. abortus by AMOS (abortus melitensis ovis suis)-polymerase chain reaction with specific primers for B. canis. One hundred percent homology of the canine isolate and the bovine pathogen isolated from the farm was demonstrated. The only possible source of infection was infected cattle on the same farm. It is suggested that dogs be routinely included in brucellosis surveillance and eradication programs.
Collapse
|
81
|
Kakoma I, Oluoch AO, Baek BK, Rahman MS, Matsuda K. More attention warranted on Brucella abortus in animals. J Am Vet Med Assoc 2003; 222:284. [PMID: 12564586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
|
82
|
Akhter K, Rahman MS, Ahmed S, Ahmed A, Alam SM. Serum calcium in normal pregnant women. Mymensingh Med J 2003; 12:55-7. [PMID: 12715646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
A prospective case-control study was done to determine any difference of serum calcium levels in pregnant women in third trimester and non-pregnant women. Serum calcium levels were determined in 30 normal non-gravid women and 30 women with normal pregnancies during third trimester with age range of 17-35 years. The mean serum calcium levels were found to be significantly lower in normal pregnant woman in third trimester than that of normal non-pregnant controls.
Collapse
|
83
|
Rahman MS, Islam MN, Mallick SA. Fertility levels, patterns and differentials in Dhaka City. RURAL DEMOGRAPHY 2002; 10:1-18. [PMID: 12340092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
|
84
|
Islam MN, Ali MA, Saha GK, Islam MF, Islam KQ, Rahman MS. Incidence and prognostic significance of right bundle branch block complicating acute myocardial infarction. BANGLADESH MEDICAL RESEARCH COUNCIL BULLETIN 2002; 28:26-35. [PMID: 12587758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The incidence and hospital courseofacute myocardial infarction wereobserved among randomly selected 560 patients. The mean age of the patients was 53 +/- 6.67 years with male-female ratio 2.6:1. The incidence of right bundle branch block (RBBB) was 15% (84 out of 560 patients). New RBBB, old RBBB and RBBB of indeterminate age were observed in 33 (39.25%), 23 (27.40%) and 28 (33.25%) cases respectively. RBBB was isolated in 50 (60%) cases and bi-fascicular in remaining 34 (40%) cases. The rate of use of thrombolytic was greater in RBBB group than non-RBBB group (52% vs 30.67%, P < 0.05). The complications were more frequently observed in patients with RBBB: in-hospital mortality, 27.40% vs 10.90% (P < 0.01); use of temporary pacemaker, 15% vs 9% (P < 0.05); and heart failure, 50% vs 35% (P < 0.05). In sub-group analysis, in-hospital mortality rate was higher among bi-fascicular group than isolated RBBB group (P < 0.05). Thus it appeared from the results that the incidence of RBBB is relatively common i.e. 15% over all (84 out of 560) and 5.90% new (33 out of 560) and despite greater use of thrombolytics, some specific in-hospital complications were significantly higher in patients with RBBB than without, RBBB.
Collapse
|
85
|
Jabber SA, Khan YS, Rahman MS. Levels of organochlorine pesticide residues in some organs of the Ganges perch, Lates calcarifer, from the Ganges-Brahmaputra-Meghna Estuary, Bangladesh. MARINE POLLUTION BULLETIN 2001; 42:1291-1296. [PMID: 11827115 DOI: 10.1016/s0025-326x(00)00161-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Levels of organochlorine pesticide residues (p,p' DDT, DDD, DDE, Aldrin, Dieldrin, Lindane, Heptachlor and BHC) were analysed in the dry and wet seasons in four organs (muscle, liver, gut and egg samples) of Ganges Perch, Lates calcarifer, collected during October-November-December, 1996 and May-June-July, 1997 from the Ganges-Brahmaputtra-Meghna estuary. The residues were analysed by using gas-chromatography (GC) in electron capture detector (ECD) mode and were verified by thin layer chromatography (TLC). Among the four organs analysed, the residues were found in the order egg > gut > muscle > liver. The pesticide residues were found in the order sigmaDDT > Heptachlor > Dieldrin > Aldrin. Higher levels of residues were found during the dry season due to high lipid content in fishes. A positive correlation was observed between the pesticide residues (sigmaDDT and sigmaOCs) and lipid contents of fish, and the correlation was found to be linear. The concentrations of pesticide residues in muscle, liver and gut were below the FAO/WHO (1993) recommended permissible limit except in eggs.
Collapse
|
86
|
Rahman MS, Tsuchiya T. Enhancement of chondrogenic differentiation of human articular chondrocytes by biodegradable polymers. TISSUE ENGINEERING 2001; 7:781-90. [PMID: 11749734 DOI: 10.1089/107632701753337726] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Biodegradable polymers are attractive candidates for chondrocyte embedding and transplantation in cartilage tissue engineering. In an attempt to determine the effects of a variety of biodegradable materials on cartilage proliferation and extracellular matrix production, poly-L-lactic acid (PLLA) with a molecular weight of 5,000, polyglycolic acid (PGA) with a molecular weight of 3,000, and copolymer of poly(L-lactic acid-glycolic acid) 50:50 (PLGA) with a molecular weight of 5,000, were dissolved in DMSO and added into the medium for 4 weeks in in vitro high-density micromass culture of multiplied human articular chondrocytes (HAC). PLLA with a molecular weight of 270,000 (PLAO3) was used as thin film. Cell proliferation and differentiation in these biomaterials were compared with tissue culture polystyrene (TCPS) as a control. Alamar blue and alcian blue staining were carried out to determine the chondrocyte proliferation and differentiation, respectively. Samples exposed to these biomaterials promoted cell proliferation in the range of 86-105% of the control proliferation, and a slight but significant increase in cell proliferation was noted only in the culture exposed to PLGA. The sample exposed to PGA elicited a significant 3.7-fold higher (p < 0.01) cell differentiation than controls and was significantly higher than that of the samples exposed to PLLA, PLAO3, and PLGA. After 4 weeks of culture, the cell differentiation from most to least was in the following order PGA > PLAO3 > PLGA = PLLA > Cont. = DMSO. Chondrocyte differentiation of the samples exposed to various biomaterials were significantly higher compared with controls. Thus, serially passage chondrocytes are competent for cell growth and quantifiable matrix production, and biodegradable polymers, especially PGA, hold promise as suitable substrates for scaffolding materials for human cartilage tissue engineering.
Collapse
|
87
|
Rahman MS, Takemura A, Takano K. Lunar synchronization of testicular development and steroidogenesis in rabbitfish. Comp Biochem Physiol B Biochem Mol Biol 2001; 129:367-73. [PMID: 11399470 DOI: 10.1016/s1096-4959(01)00323-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Lunar synchronization of testicular development in the golden rabbitfish, Siganus guttatus, was assessed by measuring changes in sperm motility and conditions in the seminal plasma, and by in vitro production of steroid hormones in testicular fragments and sperm preparations. The duration and percentage of sperm motility was low 1 week before spawning (the new moon), but increased significantly on the day of spawning (the first lunar quarter). During the first lunar quarter, the osmolality decreased, but Ca(2+) concentration increased in the seminal plasma. These results suggest that spermiation occurs rapidly towards the specific lunar phase. Testicular fragments and sperm preparations were incubated with human chorionic gonadotropin (hCG) and two precursor steroid hormones, 17alpha-hydroxyprogesterone (17alpha-OHP) and testosterone (T), during the two lunar phases. The production of 11-ketotestosterone (11-KT) increased significantly when the testicular fragments were incubated with hCG at the first lunar quarter, while incubation of sperm preparations with 17alpha-OHP during the same moon phase resulted in a significant increase in 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP) production in the medium. These results suggest that 11-KT is produced in the somatic cells of the testis under the influence of gonadotropin, and that sperm can convert 17alpha-OHP to DHP. Additionally, steroidogenic activity was considered to increase toward the specific lunar phase. The synchronous increase in testicular activity supports the hypothesis that lunar periodicity is a major factor for the testicular development of S. guttatus.
Collapse
|
88
|
Kasapis S, Rahman MS, Guizani N, Al-Aamri M. State diagram of temperature vs date solids obtained from the mature fruit. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2000; 48:3779-3784. [PMID: 10995270 DOI: 10.1021/jf9913615] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Mature dates were dried achieving an increase in the level of solids from 70.8% to 92.4% (wet basis). Small deformation dynamic oscillation was employed to identify changes in the viscoelastic properties of dates as a function of solids. Samples were cooled or heated at a constant scan rate of 1 degrees C/min. At high temperatures, e.g., 70 degrees C, the storage and loss modulus (G' and G' ', respectively) remained relatively independent of the time or frequency of observation, thus delineating the plateau zone. Cooling resulted in rapid development of both moduli with G' ' overtaking G'. This is known as the glass transition region and was used to define the rheological T(g). Eventually, the glassy state is reached where the storage modulus becomes dominant once more and approaches values of 10(9.5) Pa. The values of T(g) were used to determine the metastable glass transition curve of mature dates. At lower levels of solids, i.e., between 11.7% and 64%, freezing experiments were employed to identify the equilibrium melting curve of ice. The state diagram yielded a maximally freeze-concentrated solute at 70% solids with the characteristic temperature of glass formation being -50 degrees C. Data on equilibrium and kinetic events were modeled using the Chen and Gordon-Taylor equations yielding the rheological T(g) for date solids at their effective molecular weight.
Collapse
|
89
|
Dunman PM, Ren L, Rahman MS, Palejwala VA, Murphy HS, Volkert MR, Humayun MZ. Escherichia coli cells defective for the recN gene display constitutive elevation of mutagenesis at 3,N(4)-ethenocytosine via an SOS-induced mechanism. Mol Microbiol 2000; 37:680-6. [PMID: 10931361 DOI: 10.1046/j.1365-2958.2000.02045.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Escherichia coli UVM (UV Modulation of mutagenesis) response is a DNA damage-inducible mutagenic pathway detected as significantly increased mutagenesis at 3,N4-ethenocytosine (epsilon C) lesions borne on transfected single-stranded M13 vector DNA. All major classes of DNA-damaging agents can induce UVM, and the phenomenon is independent of previously characterized mutagenic responses in E. coli. To understand this phenomenon further, we set out to identify and characterize mutants in the UVM response. Screening a mutant bank of cells defective for 1-methyl-3-nitro-1-nitrosoguanidine-inducible genes revealed that defects in the recN gene cause a constitutive elevation of mutagenesis at epsilon C residues. In contrast to normal cells that show approximately 6% mutagenesis at epsilon C lesions, but approximately 60% upon UVM induction, recN-defective strains display approximately 50% mutagenesis at epsilon C lesion sites in untreated cells. However, the recN-mediated mutagenesis response was found to require the recA gene and the umuDC genes, and could be suppressed in the presence of a plasmid harbouring the SOS transcriptional repressor LexA. These results imply that recN cells are constitutively active for SOS mutagenesis functions. The observation that epsilonC mutagenesis is enhanced in recN cells confirms previous findings that mutagenesis at epsilonC can also be independently elevated by the SOS pathway.
Collapse
|
90
|
Al Mamun AA, Rahman MS, Humayun MZ. Escherichia coli cells bearing mutA, a mutant glyV tRNA gene, express a recA-dependent error-prone DNA replication activity. Mol Microbiol 1999; 33:732-40. [PMID: 10447883 DOI: 10.1046/j.1365-2958.1999.01520.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A base substitution mutation (mutA) in the Escherichia coli glyV tRNA gene potentiates asp --> gly mistranslation and confers a strong mutator phenotype that is SOS independent, but requires recA, recB and recC genes. Here, we demonstrate that mutA cells express an error-prone DNA polymerase by using an in vitro experimental system based on the conversion of phage M13 single-stranded viral DNA bearing a model mutagenic lesion to the double-stranded replicative form. Amplification of the newly synthesized strand followed by multiplex DNA sequence analysis revealed that mutation fixation at 3, N4-ethenocytosine (varepsilonC) was approximately 3% when the DNA was replicated by normal cell extracts, approximately 48% when replicated by mutA cell extracts and approximately 3% when replicated by mutA recA double mutant cell extracts, in complete agreement with previous in vivo results. Mutagenesis at undamaged DNA sites was significantly elevated by mutA cell-free extracts in the M13 lacZ(alpha) forward mutagenesis system. Neither polA (DNA polymerase I) nor polB (DNA polymerase II) genes are required for the mutA phenotype, suggesting that the phenotype is mediated through a modification of DNA polymerase III or the activation of a previously unidentified DNA polymerase. These findings define the major features of a novel mutagenic pathway and imply the existence of previously unrecognized links between translation, recombination and replication.
Collapse
|
91
|
Rasul CH, Hussain MA, Siddiquey AH, Rahman MS. Perinatal mortality in a teaching hospital. Indian Pediatr 1999; 36:389-91. [PMID: 10717700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
|
92
|
Wang G, Rahman MS, Humayun MZ, Taylor DE. Multiplex sequence analysis demonstrates the competitive growth advantage of the A-to-G mutants of clarithromycin-resistant Helicobacter pylori. Antimicrob Agents Chemother 1999; 43:683-5. [PMID: 10049289 PMCID: PMC89182 DOI: 10.1128/aac.43.3.683] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Clarithromycin resistance in Helicobacter pylori is due to point mutation within the 23S rRNA. We examined the growth rates of different types of site-directed mutants and demonstrated quantitatively the competitive growth advantage of A-to-G mutants over other types of mutants by a multiplex sequencing assay. The results provide a rational explanation of why A-to-G mutants are predominantly observed among clarithromycin-resistant clinical isolates.
Collapse
|
93
|
Rahman MS, Humayun MZ. SOS and UVM pathways have lesion-specific additive and competing effects on mutation fixation at replication-blocking DNA lesions. J Bacteriol 1999; 181:1515-23. [PMID: 10049383 PMCID: PMC93541 DOI: 10.1128/jb.181.5.1515-1523.1999] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli cells have multiple mutagenic pathways that are induced in response to environmental and physiological stimuli. Unlike the well-investigated classical SOS response, little is known about newly recognized pathways such as the UVM (UV modulation of mutagenesis) response. In this study, we compared the contributions of the SOS and UVM pathways on mutation fixation at two representative noninstructive DNA lesions: 3,N4-ethenocytosine (epsilonC) and abasic (AP) sites. Because both SOS and UVM responses are induced by DNA damage, and defined UVM-defective E. coli strains are not yet available, we first constructed strains in which expression of the SOS mutagenesis proteins UmuD' and UmuC (and also RecA in some cases) is uncoupled from DNA damage by being placed under the control of a heterologous lac-derived promoter. M13 single-stranded viral DNA bearing site-specific lesions was transfected into cells induced for the SOS or UVM pathway. Survival effects were determined from transfection efficiency, and mutation fixation at the lesion was analyzed by a quantitative multiplex sequence analysis procedure. Our results suggest that induction of the SOS pathway can independently elevate mutagenesis at both lesions, whereas the UVM pathway significantly elevates mutagenesis at epsilonC in an SOS-independent fashion and at AP sites in an SOS-dependent fashion. Although mutagenesis at epsilonC appears to be elevated by the induction of either the SOS or the UVM pathway, the mutational specificity profiles for epsilonC under SOS and UVM pathways are distinct. Interestingly, when both pathways are active, the UVM effect appears to predominate over the SOS effect on mutagenesis at epsilonC, but the total mutation frequency is significantly increased over that observed when each pathway is individually induced. These observations suggest that the UVM response affects mutagenesis not only at class 2 noninstructive lesions (epsilonC) but also at classical SOS-dependent (class 1) lesions such as AP sites. Our results add new layers of complexity to inducible mutagenic phenomena: DNA damage activates multiple pathways that have lesion-specific additive as well as suppressive effects on mutation fixation, and some of these pathways are not directly regulated by the SOS genetic network.
Collapse
|
94
|
Ren L, Rahman MS, Humayun MZ. Escherichia coli cells exposed to streptomycin display a mutator phenotype. J Bacteriol 1999; 181:1043-4. [PMID: 9922274 PMCID: PMC93477 DOI: 10.1128/jb.181.3.1043-1044.1999] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mistranslation mediated by the mutA and mutC tRNA alleles elicits a strong mutator phenotype (H. S. Murphy and M. Z. Humayun, J. Bacteriol. 179:7507-7514, 1997; M. M. Slupska, C. Baikalov, R. Lloyd, and J. H. Miller, Proc. Natl. Acad. Sci. USA 93:4380-4385, 1996). Here, we show that exposure to streptomycin, an antibiotic known to promote mistranslation, induces a recA- and umuDC-independent mutator phenotype detected as enhanced mutagenesis at a 3, N4-ethenocytosine lesion borne on transfected M13 single-stranded DNA.
Collapse
|
95
|
Miller D, Briggs J, Rahman MS, Griffith-Jones M, Rane V, Everett M, Lilford RJ, Bulmer JN. Transcervical recovery of fetal cells from the lower uterine pole: reliability of recovery and histological/immunocytochemical analysis of recovered cell populations. Hum Reprod 1999; 14:521-31. [PMID: 10100004 DOI: 10.1093/humrep/14.2.521] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The aim of this work was to isolate, enumerate and attempt the identification of fetal cells recovered from the lower uterine pole. Immediately before elective termination of pregnancy at 7-17 weeks gestation, samples were recovered by transcervical flushing of the lower uterine pole (n = 108) or transcervical aspiration of mucus from just above the internal os (n = 187), and their contents examined using histological, immunohistochemical and molecular techniques. Syncytiotrophoblasts were identified morphologically in 28 out of 89 (31%) and 50 out of 180 (28%) flushings and aspirates respectively (mean 29%). Immunocytochemistry with monoclonal antibodies (mAbs) recognizing trophoblast or epithelial cell antigens on a smaller number of samples (n = 69) identified putative placental cells in 13 out of 19 (68%) and 25 out of 50 (50%) flushings and aspirates respectively (mean 55%). These included groups of distinctive cells with a small, round, hyperchromatic nucleus, strongly reactive with mAbs PLAP, NDOG1 and FT1.41.1. Smaller groups of larger, amorphous cells, usually containing multiple large, pale staining nuclei, reactive with mAb 340 and to a lesser degree with mAb NDOG5 were also observed. Taking cellular morphology and immunophenotype into consideration, the smaller uninucleate cells were likely to be villous mesenchymal cells, while the larger cells were possibly degrading villous syncytiotrophoblast. There was no significant difference in the frequency of fetal cells obtained by the two recovery methods. Squamous or columnar epithelial cells, labelled strongly with antibodies to cytokeratins or human milk fat globule protein, were observed in 97% (29 out of 30) of aspirates. The use of cervagem in a small number of patients prior to termination of pregnancy did not appear to influence the subsequent recovery of placental cells. Y-specific DNA was detected by polymerase chain reaction (PCR) in 13 out of 26 (50%) flushings and (99 out of 154) 64% aspirates analysed (mean 62%). In-situ hybridization (ISH) revealed Y-specific targets in 40 out of 69 (60%) of aspirates analysed. A comparison of PCR data obtained from transcervical recovered samples and placental tissues showed a concordance of 80% (76 out of 95), with 10 false positives. Comparing the PCR data from tissues with data derived by ISH from 41 aspirates gave a concordance of 90% with two false positives. Although syncytiotrophoblasts were much more likely to be present in samples containing immunoreactive placental cells, the detection rates of fetal-derived DNA were similar regardless of the morphological and/or immunological presence of placental cells. We conclude that the transcervical recovery of fetal cells, while promising, requires considerable additional effort being expended in further research and development, particular in the sampling procedure.
Collapse
|
96
|
Al-Jama FE, Rahman J, Al-Suleiman SA, Rahman MS. Outcome of pregnancy in women with idiopathic thrombocytopenic purpura. Aust N Z J Obstet Gynaecol 1998; 38:410-3. [PMID: 9890221 DOI: 10.1111/j.1479-828x.1998.tb03099.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The obstetric management and haematological problems in 28 pregnancies of 23 mothers with idiopathic thrombocytopenic purpura (ITP) are analyzed. There was no maternal death and only 1 stillbirth occurred in the series. Ten infants were born by Caesarean section and 18 were delivered vaginally. Neonatal cord bloodplatelet counts showed thrombocytopenia in 12 infants, but in only 4 (14.3%) was the cord blood platelet count <50 x 10(9)/L. None of the 27 liveborn infants died, although 4 required supportive treatment with corticosteroids and IgG. No maternal characteristics could be used to predict the neonatal platelet count. These results are comparable with other studies reported in the literature. The rarity of poor neonatal outcome in mothers with ITP does not justify obstetric intervention solely on the basis of their platelet counts. The management of patients should be individualized and carefully planned.
Collapse
|
97
|
Rahman MS, Grace JJ, Pato MT, Priest B. Sertraline in the treatment of clozapine-induced obsessive-compulsive behavior. Am J Psychiatry 1998; 155:1629-30. [PMID: 9812137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
|
98
|
Taguchi T, Nakao M, Yanai K, Rahman MS, Yamada T, Suita S. Comparison of jejunal and ileal grafts from the aspects of cold preservation and immunologic reaction. Transplant Proc 1998; 30:2636-7. [PMID: 9745523 DOI: 10.1016/s0041-1345(98)00759-3] [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: 11/29/2022]
|
99
|
Taguchi T, Guo R, Masumoto K, Nada O, Rahman MS, Nakao M, Yanai K, Suita S. Distribution in nitric oxide neurons after rat small intestinal transplantation. Transplant Proc 1998; 30:2626. [PMID: 9745519 DOI: 10.1016/s0041-1345(98)00755-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
100
|
Rahman MS, Taguchi T, Masumoto K, Guo R, Nakao M, Yanai K, Suita S, Nada O, Ohta M. Efficacy of cytologic examination of luminal exudate in monitoring acute rejection of rat intestinal allografts. Transplant Proc 1998; 30:2653. [PMID: 9745534 DOI: 10.1016/s0041-1345(98)00775-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
|