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1.
Curr Biol ; 10(6): 337-40, 2000 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-10744977

RESUMEN

The RAD52 epistasis group was identified in yeast as a group of genes required to repair DNA damaged by ionizing radiation [1]. Genetic evidence indicates that Rad52 functions in Rad51-dependent and Rad51-independent recombination pathways [2] [3] [4]. Consistent with this, purified yeast and human Rad52 proteins have been shown to promote single-strand DNA annealing [5] [6] [7] and to stimulate Rad51-mediated homologous pairing [8] [9] [10] [11]. Electron microscopic examinations of the yeast [12] and human [13] Rad52 proteins have revealed their assembly into ring-like structures in vitro. Using both conventional transmission electron microscopy and scanning transmission electron microscopy (STEM), we found that the human Rad52 protein forms heptameric rings. A three-dimensional (3D) reconstruction revealed that the heptamer has a large central channel. Like the hexameric helicases such as Escherichia coli DnaB [14] [15], bacteriophage T7 gp4b [16] [17], simian virus 40 (SV40) large T antigen [18] and papilloma virus E1 [19], the Rad52 rings show a distinctly chiral arrangement of subunits. Thus, the structures formed by the hexameric helicases may be a more general property of other proteins involved in DNA metabolism, including those, such as Rad52, that do not bind and hydrolyze ATP.


Asunto(s)
Proteínas de Unión al ADN/ultraestructura , Animales , Línea Celular , Humanos , Proteína Recombinante y Reparadora de ADN Rad52 , Proteínas Recombinantes de Fusión/ultraestructura
2.
Mol Cell Biol ; 18(5): 2976-85, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9566917

RESUMEN

Mitochondrial DNA (mtDNA) of Saccharomyces cerevisiae contains highly conserved sequences, called rep/ori, that are associated with several aspects of its metabolism. These rep/ori sequences confer the transmission advantage exhibited by a class of deletion mutants called hypersuppressive petite mutants. In addition, because they share features with the mitochondrial leading-strand DNA replication origin of mammals, rep/ori sequences have also been proposed to participate in mtDNA replication initiation. Like the mammalian origins, where transcription is used as a priming mechanism for DNA synthesis, yeast rep/ori sequences contain an active promoter. Although transcription is required for maintenance of wild-type mtDNA in yeast, the role of the rep/ori promoter as a cis-acting element involved in the replication of wild-type mtDNA is unclear, since mitochondrial deletion mutants need neither transcription nor a rep/ori sequence to maintain their genome. Similarly, transcription from the rep/ori promoter does not seem to be necessary for biased inheritance of mtDNA. As a step to elucidate the function of the rep/ori promoter, we have attempted to detect transcription-dependent DNA transactions in the mtDNA of a hypersuppressive petite mutant. We have examined the mtDNA of the well-characterized petite mutant a-1/1R/Z1, whose repeat unit shelters the rep/ori sequence ori1, in strains carrying either wild-type or null alleles of the nuclear genes encoding the mitochondrial transcription apparatus. Complex DNA transactions were detected that take place around GC-cluster C, an evolutionarily conserved GC-rich sequence block immediately downstream from the rep/ori promoter. These transactions are strictly dependent upon mitochondrial transcription.


Asunto(s)
ADN Mitocondrial/metabolismo , ARN/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Transcripción Genética , Replicación del ADN , Proteínas de Unión al ADN/metabolismo , Endonucleasas/genética , Endonucleasas/metabolismo , Genes Fúngicos , Proteínas del Grupo de Alta Movilidad/metabolismo , Mutación , ARN Mitocondrial , Origen de Réplica , Supresión Genética , Factores de Transcripción/metabolismo
3.
J Mol Biol ; 284(4): 1027-38, 1998 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9837724

RESUMEN

The human Rad52 protein stimulates joint molecule formation by hRad51, a homologue of Escherichia coli RecA protein. Electron microscopic analysis of hRad52 shows that it self-associates to form ring structures with a diameter of approximately 10 nm. Each ring contains a hole at its centre. hRad52 binds to single and double-stranded DNA. In the ssDNA-hRad52 complexes, hRad52 was distributed along the length of the DNA, which exhibited a characteristic "beads on a string" appearance. At higher concentrations of hRad52, "super-rings" (approximately 30 nm) were observed and the ssDNA was collapsed upon itself. In contrast, in dsDNA-hRad52 complexes, some regions of the DNA remained protein-free while others, containing hRad52, interacted to form large protein-DNA networks. Saturating concentrations of hRad51 displaced hRad52 from ssDNA, whereas dsDNA-Rad52 complexes (networks) were more resistant to hRad51 invasion and nucleoprotein filament formation. When Rad52-Rad51-DNA complexes were probed with gold-conjugated hRad52 antibodies, the presence of globular hRad52 structures within the Rad51 nucleoprotein filament was observed. These data provide the first direct visualisation of protein-DNA complexes formed by the human Rad51 and Rad52 recombination/repair proteins.


Asunto(s)
Proteínas de Unión al ADN/química , ADN/química , Animales , Baculoviridae/genética , Línea Celular , ADN/ultraestructura , Reparación del ADN , ADN de Cadena Simple/química , ADN de Cadena Simple/ultraestructura , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/ultraestructura , Humanos , Técnicas In Vitro , Sustancias Macromoleculares , Microscopía Electrónica , Unión Proteica , Conformación Proteica , Recombinasa Rad51 , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/ultraestructura , Spodoptera
4.
J Mol Biol ; 304(2): 151-64, 2000 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-11080452

RESUMEN

The human Rad51 recombinase is essential for the repair of double-strand breaks in DNA that occur in somatic cells after exposure to ionising irradiation, or in germ line cells undergoing meiotic recombination. The initiation of double-strand break repair is thought to involve resection of the double-strand break to produce 3'-ended single-stranded (ss) tails that invade homologous duplex DNA. Here, we have used purified proteins to set up a defined in vitro system for the initial strand invasion step of double-strand break repair. We show that (i) hRad51 binds to the ssDNA of tailed duplex DNA molecules, and (ii) hRad51 catalyses the invasion of tailed duplex DNA into homologous covalently closed DNA. Invasion is stimulated by the single-strand DNA binding protein RPA, and by the hRad52 protein. Strikingly, hRad51 forms terminal nucleoprotein filaments on either 3' or 5'-ssDNA tails and promotes strand invasion without regard for the polarity of the tail. Taken together, these results show that hRad51 is recruited to regions of ssDNA occurring at resected double-strand breaks, and that hRad51 shows no intrinsic polarity preference at the strand invasion step that initiates double-strand break repair.


Asunto(s)
Reparación del ADN/genética , Proteínas de Unión al ADN/metabolismo , ADN/genética , ADN/metabolismo , ADN/química , ADN/ultraestructura , ADN de Cadena Simple/química , ADN de Cadena Simple/genética , ADN de Cadena Simple/metabolismo , ADN de Cadena Simple/ultraestructura , ADN Superhelicoidal/química , ADN Superhelicoidal/genética , ADN Superhelicoidal/metabolismo , ADN Superhelicoidal/ultraestructura , Proteínas de Unión al ADN/ultraestructura , Humanos , Microscopía Electrónica , Modelos Genéticos , Conformación de Ácido Nucleico , Unión Proteica , Recombinasa Rad51 , Rec A Recombinasas/metabolismo , Recombinación Genética/genética , Proteína de Replicación A , Homología de Secuencia de Ácido Nucleico
5.
AIDS ; 6(5): 489-93, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1616655

RESUMEN

OBJECTIVE: To investigate whether genital ulcer diseases are cofactors which enhance the transmission of HIV-2 in West Africa. DESIGN: A cross-sectional study of 435 men presenting with a sexually transmitted disease (STD). SETTING: The outpatient clinic of the Medical Research Council Laboratories, a primary care facility in Fajara, a suburb of Banjul, the capital city of The Gambia (West Africa). PATIENTS, PARTICIPANTS: Six hundred and twenty-four men presenting with a genital complaint, of whom 443 had an STD. Eight of the men with an STD were excluded from further analysis because they were HIV-1-infected (five patients) or had indeterminate Western blot patterns (three patients). The remaining 21 HIV-2-infected and 414 seronegative men constituted our study-group. MAIN OUTCOME MEASURES: Participants were questioned about previous STD and behavioural and demographic characteristics. A physical examination was performed and serum collected for measurement of antibodies against Haemophilus ducreyi and Treponema pallidum. RESULTS: HIV-2-infected men were more likely than HIV-seronegative participants to have previously had a genital ulcer [odds ratio (OR), 3.00; 95% confidence interval (Cl), 1.18-7.60] and to have antibodies against T. pallidum (OR, 5.95; 95% Cl, 2.10-16.91), or H. ducreyi (OR, 4.59; 95% Cl, 1.71-12.33). Circumcised patients with residual foreskin were more likely to be HIV-2 infected than patients with complete circumcision. HIV-2-seropositive patients were six times more likely to have generalized lymphadenopathy than their seronegative counterparts. CONCLUSIONS: Our data suggest that genital ulcerative diseases, such as syphilis and chancroid, are probably cofactors that increase the transmission of HIV-2 in West Africa, and that HIV-2 infection frequently results in generalized lymphadenopathy.


Asunto(s)
Enfermedades de los Genitales Masculinos/complicaciones , Infecciones por VIH/complicaciones , VIH-2 , Enfermedades de Transmisión Sexual/complicaciones , Úlcera Cutánea/complicaciones , Adolescente , Adulto , Anciano , Gambia/epidemiología , Enfermedades de los Genitales Masculinos/epidemiología , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Úlcera Cutánea/epidemiología
6.
AIDS ; 5(6): 715-21, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1883543

RESUMEN

In 1988, 1233 prostitutes from different geographic areas of Kinshasa participated in a cross-sectional survey on HIV infection and other sexually transmitted diseases (STDs). Despite relatively good knowledge about AIDS and STDs, the reported preventive behaviour was poor. Only 12% of the women reported regular use of condoms, while greater than 50% of the women reported regular use of antibiotics and 38% reported doing nothing specific to prevent STDs. Thirty-five per cent of the women were HIV-positive compared with 27% in a similar survey in Kinshasa in 1986. The prevalence of other STDs was very high, ranging from 5% for genital ulcer disease (GUD) to 23% for gonococcal infection. HIV-positive women were older than HIV-negative women (26.9 versus 25.4 years; P less than 0.001), had a significantly lower level of reported condom use (9 versus 14%, P = 0.009), and reported more frequent use of antibiotics to prevent STDs (55 versus 42%, P = less than 0.001). The prevalence of syphilis, gonorrhoea, chlamydial infection and trichomoniasis was not higher in HIV-positive women compared with HIV-negative women. However, HIV-positive women had a higher prevalence of GUD (9 versus 3%, P less than 0.001), antibodies against Haemophilus ducreyi (82 versus 57%, P less than 0.001), antibodies against herpes simplex virus type 2 (96 versus 76%, P less than 0.001), condylomata accuminata (5 versus 1%, P = 0.003) and cytologic evidence of human papilloma virus on Papaniclaou cervical smear (11 versus 5%, P = 0.006). This study confirms the high incidence of HIV and other STDs among prostitutes in Africa.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Infecciones por VIH/epidemiología , Trabajo Sexual , Enfermedades de Transmisión Sexual/epidemiología , Adolescente , Adulto , África/epidemiología , Antibacterianos/uso terapéutico , Dispositivos Anticonceptivos Masculinos , Estudios Transversales , Femenino , Infecciones por VIH/prevención & control , Humanos , Análisis Multivariante , Prevalencia , Factores de Riesgo , Enfermedades de Transmisión Sexual/prevención & control
7.
AIDS ; 15 Suppl 4: S79-88, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11686469

RESUMEN

OBJECTIVES: To compare the epidemiology of gonorrhoea, chlamydial infection and syphilis in four cities in sub-Saharan Africa; two with a high prevalence of HIV infection (Kisumu, Kenya and Ndola, Zambia), and two with a relatively low HIV prevalence (Cotonou, Benin and Yaoundé, Cameroon). DESIGN: Cross-sectional study, using standardized methods, including a standardized questionnaire and standardized laboratory tests, in four cities in sub-Saharan Africa. METHODS: In each city, a random sample of about 2000 adults aged 15-49 years was taken. Consenting men and women were interviewed about their socio-demographic characteristics and their sexual behaviour, and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection, and (women only) Trichomonas vaginalis infection. Risk factor analyses were carried out for chlamydial infection and syphilis seroreactivity. RESULTS: The prevalence of gonorrhoea ranged between 0% in men in Kisumu and 2.7% in women in Yaoundé. Men and women in Yaoundé had the highest prevalence of chlamydial infection (5.9 and 9.4%, respectively). In the other cities, the prevalence of chlamydial infection ranged between 1.3% in women in Cotonou and 4.5% in women in Kisumu. In Ndola, the prevalence of syphilis seroreactivity was over 10% in both men and women; it was around 6% in Yaoundé, 3-4% in Kisumu, and 1-2% in Cotonou. Chlamydial infection was associated with rate of partner change for both men and women, and with young age for women. At the population level, the prevalence of chlamydial infection correlated well with reported rates of partner change. Positive syphilis serology was associated with rate of partner change and with HSV-2 infection. The latter association could be due to biological interaction between syphilis and HSV-2 or to residual confounding by sexual behaviour. At the population level, there was no correlation between prevalence of syphilis seroreactivity and reported rates of partner change. CONCLUSION: Differences in prevalence of chlamydial infection could be explained by differences in reported sexual behaviour, but the variations in prevalence of syphilis seroreactivity remained unexplained. More research is needed to better understand the epidemiology of sexually transmitted infections in Africa.


Asunto(s)
Infecciones por Chlamydia/epidemiología , Gonorrea/epidemiología , Sífilis/epidemiología , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Anticuerpos Antibacterianos/sangre , Chlamydia trachomatis/aislamiento & purificación , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Neisseria gonorrhoeae , Prevalencia , Factores de Riesgo , Treponema pallidum/inmunología , Treponema pallidum/aislamiento & purificación , Población Urbana
8.
AIDS ; 15 Suppl 4: S89-96, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11686470

RESUMEN

OBJECTIVES: To describe the epidemiology of Trichomonas vaginalis infection and its association with HIV infection, in women in four African cities with different levels of HIV infection. DESIGN: Cross-sectional study, using standardized methods, including a standardized questionnaire and standardized laboratory tests, in four cities in sub-Saharan Africa: two with a high prevalence of HIV infection (Kisumu, Kenya and Ndola, Zambia), and two with a relatively low prevalence of HIV (Cotonou, Benin and Yaoundé, Cameroon). METHODS: In each city, a random sample of about 2000 adults aged 15-49 years was taken. Consenting men and women were interviewed about their socio-demographic characteristics and their sexual behaviour, and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection, and (women only) T. vaginalis infection. Risk factor analyses were carried out for trichomoniasis for each city separately. Multivariate analysis, however, was only possible for Yaoundé, Kisumu and Ndola. RESULTS: The prevalence of trichomoniasis was significantly higher in the high HIV prevalence cities (29.3% in Kisumu and 34.3% in Ndola) than in Cotonou (3.2%) and Yaoundé (17.6%). Risk of trichomoniasis was increased in women who reported more lifetime sex partners. HIV infection was an independent risk factor for trichomonas infection in Yaoundé [adjusted odds ratio (OR) = 1.8, 95% confidence interval (CI) = 0.9-3.7] and Kisumu (adjusted OR = 1.7, 95% CI = 1.1-2.7), but not in Ndola. A striking finding was the high prevalence (40%) of trichomonas infection in women in Ndola who denied that they had ever had sex. CONCLUSION: Trichomoniasis may have played a role in the spread of HIV in sub-Saharan Africa and may be one of the factors explaining the differences in levels of HIV infection between different regions in Africa. The differences in prevalence of trichomoniasis between the four cities remain unexplained, but we lack data on the epidemiology of trichomoniasis in men. More research is required on the interaction between trichomoniasis and HIV infection, the epidemiology of trichomoniasis in men, and trichomonas infections in women who deny sexual activity.


Asunto(s)
Vaginitis por Trichomonas/epidemiología , Trichomonas vaginalis , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Animales , Estudios Transversales , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Humanos , Persona de Mediana Edad , Prevalencia , Distribución Aleatoria , Factores de Riesgo , Conducta Sexual , Encuestas y Cuestionarios , Vaginitis por Trichomonas/parasitología
9.
AIDS ; 15 Suppl 4: S97-108, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11686471

RESUMEN

OBJECTIVES: To estimate age- and sex-specific herpes simplex virus type-2 (HSV-2) prevalence in urban African adult populations and to identify factors associated with infection. DESIGN AND METHODS: Cross-sectional, population-based samples of about 2000 adults interviewed in each of the following cities: Cotonou, Benin; Yaoundé, Cameroon; Kisumu, Kenya and Ndola, Zambia. Consenting study participants were tested for HIV, HSV-2 and other sexually transmitted infections. RESULTS: HSV-2 prevalence was over 50% among women and over 25% among men in Yaoundé, Kisumu and Ndola, with notably high rates of infection among young women in Kisumu and Ndola (39% and 23%, respectively, among women aged 15-19 years). The prevalence in Cotonou was lower (30% in women and 12% in men). Multivariate analysis showed that HSV-2 prevalence was significantly associated with older age, ever being married, and number of lifetime sexual partners, in almost all cities and both sexes. There was also a strong, consistent association with HIV infection. Among women, the adjusted odds ratios for the association between HSV-2 and HIV infections ranged from 4.0 [95% confidence interval (CI) = 2.0-8.0] in Kisumu to 5.5 (95% CI = 1.7-18) in Yaoundé, and those among men ranged from 4.6 (95% CI = 2.7-7.7) in Ndola to 7.9 (95% CI = 4.1-15) in Kisumu. CONCLUSIONS: HSV-2 infection is highly prevalent in these populations, even at young ages, and is strongly associated with HIV at an individual level. At a population level, HSV-2 prevalence was highest in Kisumu and Ndola, the cities with the highest HIV rates, although rates were also high among women in Yaoundé, where there are high rates of partner change but relatively little HIV infection. The high prevalence of both infections among young people underlines the need for education and counselling among adolescents.


Asunto(s)
Infecciones por VIH/complicaciones , Herpes Genital/epidemiología , Población Urbana , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Distribución por Edad , Anticuerpos Antivirales/sangre , Estudios Transversales , Femenino , Anticuerpos Anti-VIH/sangre , Infecciones por VIH/epidemiología , VIH-1/inmunología , Herpes Genital/transmisión , Herpes Genital/virología , Herpesvirus Humano 2/inmunología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , Factores de Riesgo , Distribución por Sexo , Enfermedades de Transmisión Sexual/complicaciones , Enfermedades de Transmisión Sexual/epidemiología
10.
Gene ; 229(1-2): 37-45, 1999 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-10095102

RESUMEN

In the frame of the European Network for Functional Analysis (EUROFAN), two regions from chromosome XI covering 54kb have been subjected to 'mass-murder'. Ten deletions covering 23 novel open reading frames (ORFs) were constructed in haploid and diploid strains. Six deletions were lethal in haploid strains. One deletion caused slow germination of spores and slow cellular growth, and another one was associated with both cellular growth thermosensitivity and poor growth on glycerol. These two defects were assigned to two different genes. All mutant phenotypes were complemented by a single gene, enabling us to identify five genes essential for vegetative growth, three genes with detectable phenotype and 15 dispensable genes under standard physiological conditions.


Asunto(s)
Eliminación de Gen , Genes Fúngicos/genética , Sistemas de Lectura Abierta/genética , Saccharomyces cerevisiae/genética , División Celular/genética , Cromosomas/genética , Cartilla de ADN/genética , Prueba de Complementación Genética , Mutación/genética , Fenotipo , Esporas/genética
11.
Int J Epidemiol ; 9(3): 239-45, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7440047

RESUMEN

The annual incidence of urethritis can be estimated to be at lest 3750 per 100,000 population in Swaziland. In a study of 109 males with symptomatic urethritis 80% had gonorrhoea, 6% non-gonococcal urethritis (ngu) and 14% were classified as having no 'objective' urethritis (less than 5 polymorphonuclear leucocytes per highpower field in the urethral smear). The relative frequency of gonorrhoea was 80 to 95% and of non-gonococcal urethritis 5 to 20 according to which criteria are used for patient selection and/or diagnosis of ngu. Chlamydia trachomatis was cultured in 3.4% of the cases with urethritis, comprising one positive culture in 70 patients with gonorrhoea, one in 5 with ngu, and one in 12 with no 'objective' urethritis. Seventy-one percent of patients, with a comparable percentage in each diagnostic group, had chlamydial antibodies when tested by the micro immunofluorescence test to pooled chlamydial antigens. Interpretation of the chlamydial serologic results indicates that lymphogranuloma venereum is probably endemic in the country, and that oculogenital chlamydial infections are not a problem; this corresponds with the low isolation rate of Chlamydia trachomatis in the urethritis cases. The study shows that the epidemiology and causes of urethritis are clearly of a different pattern to that seen in industrialised countries. This type of study is a sound basis for a simplified but effective urethritis control programme which can be implemented in the para-urban and rural health centres in developing countries.


Asunto(s)
Infecciones por Chlamydia , Gonorrea , Uretritis/etiología , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis , Esuatini , Gonorrea/epidemiología , Humanos , Masculino , Uretritis/diagnóstico , Uretritis/epidemiología
12.
J Med Microbiol ; 15(1): 97-103, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6982973

RESUMEN

The preliminary characterisation of an unusual gram-negative bacillus isolated from genital ulcers in Swaziland is reported. Like Haemophilus ducreyi, it is an oxidase positive, nitrate-reductase-positive gram-negative rod that forms streptobacillary chains in some circumstances; it was therefore called the "ducreyi-like bacterium" (DLB). Distinguishing features of DLB are production of alpha-haemolysis on horse-blood agar, stimulation of growth by a microaerophilic atmosphere and by a factor produced by Staphylococcus aureus, a strongly positive porphyrin test, and a remarkable ability to undergo autolysis. DLB had a guanine + cytosine value of c. 50 mole% but it cannot be classified, even at the genus level, until more taxonomic data are obtained.


Asunto(s)
Bacterias/aislamiento & purificación , Enfermedades de los Genitales Femeninos/microbiología , Enfermedades de los Genitales Masculinos/microbiología , Úlcera/microbiología , Bacterias/crecimiento & desarrollo , Bacterias/ultraestructura , Composición de Base , ADN/análisis , Esuatini , Femenino , Haemophilus ducreyi/crecimiento & desarrollo , Humanos , Masculino , Microscopía Electrónica
13.
Trans R Soc Trop Med Hyg ; 92(1): 105-7, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9692169

RESUMEN

Antimicrobial susceptibilities of Neisseria gonorrhoeae isolates from female sex workers and from men with urethritis in Bandung, Indonesia, were determined by an agar dilution technique. Typing of the Tet M plasmid in tetracycline-resistant isolates (TRNG) was performed using a polymerase chain reaction (PCR) technique and plasmid profiles of penicillinase-producing isolates (PPNG) were determined. All PPNG possessed the 4.4 MDa beta-lactamase plasmid and all TRNG showed a PCR fragment characteristic of the 'Dutch' type Tet M plasmid. Of the 50 gonococci isolates tested, all were resistant to tetracycline; 47 were TRNG, 26 were PPNG, and 6 were resistant to thiamphenicol. Chromosomal resistance to penicillin was not detected. All isolates were susceptible to ceftriaxone, ciprofloxacin, norfloxacin, ofloxacin, kanamycin, spectinomycin, and trimethoprim/sulfamethoxazole. Spectinomycin and fluoroquinolones are useful primary drugs for treatment of gonococcal infection in Bandung. Continued surveillance of antimicrobial resistance should be part of gonorrhoea control in Indonesia.


Asunto(s)
Antibacterianos/uso terapéutico , Neisseria gonorrhoeae/efectos de los fármacos , Neisseria gonorrhoeae/genética , Plásmidos/análisis , Femenino , Gonorrea/tratamiento farmacológico , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa , Resistencia a la Tetraciclina , Uretritis/microbiología
14.
Int J STD AIDS ; 12(5): 299-301, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368802

RESUMEN

The aim of this study was to evaluate the performance of rapid plasma reagin (RPR) testing using expired and adversely stored antigen reagent. The sensitivity of RPR using antigen stored at 36 degrees C was compared at 3-monthly intervals with RPR using fresh antigen on 116 sera reactive by RPR and by Treponema pallidum particle agglutination (TPPA). After multiple phases of freezing and thawing, 8.3% of initial RPR reactive sera seroreverted. After storage at 36 degrees C for one year and 24 weeks after expiration the overall sensitivity of the adversely stored antigen was 93.8% compared with fresh antigen; the sensitivity was 100% for sera with RPR titres > or = 1:4 and 85.4% for sera with RPR titres of 1:1 and 1:2. The high stability of the reagent may increase the feasibility of the RPR test for use in poorly-equipped healthcare centres in developing countries.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Cardiolipinas/inmunología , Indicadores y Reactivos/normas , Reaginas/inmunología , Sífilis/diagnóstico , Anticuerpos Antibacterianos/sangre , Humanos , Reaginas/sangre , Sífilis/inmunología , Factores de Tiempo , Treponema pallidum/inmunología
15.
Int J STD AIDS ; 12(12): 797-803, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11779370

RESUMEN

Detection of Haemophilus ducreyi in genital ulcer specimens by culture lacks sensitivity. To enhance detection, a heminested polymerase chain reaction (PCR) assay was developed targeting the nucleotide sequence of a gene, designated p27, which encodes for a 27 kDa H. ducreyi-specific protein. The p27 PCR assay detected all (37/37) H. ducreyi strains tested and gave no amplified product from DNA extracts of any of 31 other microorganisms, from 30 non-genital ulcer specimens, or from 29 urethral and vaginal swab specimens collected from non-chancroid STD patients. In genital ulcer disease specimens, compared to combined positive results obtained by culture and a previously described PCR assay, the p27 PCR assay showed a sensitivity of 91% (48/53). The p27 PCR assay provides a specific and a sensitive detection of H. ducreyi in clinical specimens.


Asunto(s)
Chancroide/microbiología , Enfermedades de los Genitales Masculinos/microbiología , Haemophilus ducreyi/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Proteínas Bacterianas/análisis , ADN Bacteriano/análisis , Haemophilus ducreyi/genética , Humanos , Masculino , Valor Predictivo de las Pruebas
16.
Int J STD AIDS ; 12(2): 89-93, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11236110

RESUMEN

This study describes antimicrobial susceptibility patterns of Neisseria gonorrhoeae isolates obtained from female sex workers in Cotonou, Bénin. All isolates were susceptible to spectinomycin, ceftriaxone and ciprofloxacin, and susceptible to moderately susceptible to kanamycin; 9.8% of isolates were resistant to thiamphenicol; 9%, 87.5% and 3.5% were susceptible, moderately susceptible, resistant to trimethoprim-sulfamethoxazole, respectively; 94.4% and 99.3% were resistant to penicillin and tetracycline, respectively. All isolates with a minimal inhibitory concentration of tetracycline of >8 mg/l carried the 'American type' tetM plasmid; 94% and 6% of penicillinase-producing isolates possessed a 3.2 MDa and a 4.4MDa beta-lactamase plasmid, respectively. Surveillance of antimicrobial susceptibility of N. gonorrhoeae isolates to currently used drugs in Africa should become part of sexually transmitted diseases (STDs) control programmes.


Asunto(s)
Antibacterianos/farmacología , Neisseria gonorrhoeae/efectos de los fármacos , Neisseria gonorrhoeae/genética , Plásmidos/genética , Benin/epidemiología , Farmacorresistencia Microbiana/genética , Electroforesis en Gel de Agar , Femenino , Gonorrea/epidemiología , Gonorrea/transmisión , Humanos , Pruebas de Sensibilidad Microbiana , Neisseria gonorrhoeae/aislamiento & purificación , Plásmidos/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Trabajo Sexual
17.
Int J STD AIDS ; 6(5): 345-7, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8547415

RESUMEN

A cohort of 650 prostitutes from Kinshasa, Zaire, was followed at monthly intervals for sexually transmitted diseases as part of an HIV intervention project. Neisseria gonorrhoeae isolates, obtained during a period of 30 months, were auxotyped, serotyped and tested for antimicrobial susceptibility. Among 1085 gonococcal isolates tested, 725 (67%) produced beta-lactamase (PPNG) and 323 (30%) showed plasmid-mediated resistance to tetracyline (TRNG). Over time, the prevalence of PPNG varied between 60 and 73%, while the level of TRNG increased from 11 to 45%.


PIP: During May 1988-October 1990 in Zaire, Neisseria gonorrhoeae isolates were obtained from 650 initially HIV-negative prostitutes in Kinshasa who were followed monthly for 30 months. After conservation of the gonococci, the N. gonorrhoeae isolates were then transported to the Institute of Tropical Medicine in Antwerp, Belgium, to test for antimicrobial resistance, especially tetracycline resistant isolates of N. gonorrhoeae. Among the 1085 isolates, 67% were resistant to penicillin (i.e., penicillinase producing N. gonorrhoeae [PPNG]). 30% exhibited plasmid-mediated resistance to tetracycline (TRNG). 37% were resistant to thiamphenicol. Thiamphenicol resistance was more common in non-TRNG isolates than TRNG isolates (49% vs. 8%; p 0.0001). The frequency of TRNG among PPNG isolates was higher than it was among non-PPNG isolates (37% vs. 16%; p 0.001). PPNG prevalence ranged from 60% to 73%. TRNG prevalence increased steadily from 11% to 45% during the 30-month period. Both TRNG and PPNG isolates were significantly associated with the auxotype/serovar class Pro-/IA-6 (p 0.0001 and p = 0.0002, respectively). They were also associated with growth inhibition by 0.25 mM phenylalanine (p 0.0001 and p = 0.001, respectively). The number of different TRNG auxotype/serovar classes ranged from 6 to 13. It has been suggested that tetracycline use to control gonorrhea in the US and in the Netherlands increased the frequency and spread of TRNG. Only spectinomycin and ciprofloxacin were used to treat gonorrhea in this study. Yet, tetracycline was prescribed for genital Chlamydia trachomatis infection, which many of the prostitutes had. Also, males self-medicate for urethritis with tetracycline. Populations with a high incidence of gonococcal infections may experience an epidemic spread of TRNG.


Asunto(s)
Gonorrea/epidemiología , Gonorrea/microbiología , Neisseria gonorrhoeae/clasificación , Factores R , Trabajo Sexual , Resistencia a la Tetraciclina , República Democrática del Congo/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Pruebas de Sensibilidad Microbiana , Vigilancia de la Población , Prevalencia , Serotipificación , Salud Urbana
18.
Int J STD AIDS ; 9(11): 706-10, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9863586

RESUMEN

During 1986-88 and 1990-92, 1025 (97%) out of 1057 genital ulcer patients in Kigali, Rwanda, were tested for HIV antibodies and for infection with Treponema pallidum, Haemophilus ducreyi and herpes simplex virus. Overall, 57% of men and 80% of women had antibodies to HIV-1. The most frequent laboratory diagnoses were chancroid (27%), syphilis (19%) and genital herpes (19%) among men and syphilis (35%), genital herpes (23%) and chancroid (20%) among women. HIV-1 seroprevalence increased sharply over time among men but not among women. The clinical presentation of ulcers as well as laboratory diagnoses were similar in the HIV-1 seropositive and seronegative groups. The relative frequency of all laboratory diagnoses remained unchanged over time. HIV-1 seropositivity had no impact on ulcer healing. Advanced immunodeficiency was diagnosed among 12% of the HIV-1 seropositive patients and was significantly associated with increasing age and genital herpes.


PIP: A study conducted at the Centre Medico-Social de Bilyogo, a primary health clinic located in an area of Nyamirambo, Kigali (Rwanda), where prostitution is widespread, assessed the frequencies of the causes of genital ulcer disease. Out of 1057 consecutive genital ulcer patients tested in 1986-88, 57% of men and 80% of women were infected with HIV-1. The most frequent laboratory diagnoses were chancroid (27%), syphilis (19%), and genital herpes (19%) among men and syphilis (35%), genital herpes (23%), and chancroid (20%) among women. During follow-up in 1990-92, HIV-1 seroprevalence increased sharply among men of all ages and women under 30 years of age. HIV-1 seropositivity had no effect on the clinical presentation of ulcers or on the time required for ulcer healing. Advanced immunodeficiency, diagnosed among 12% of HIV-positive patients, was significantly associated with increasing age and genital herpes.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Chancro/epidemiología , Chancroide/epidemiología , Seroprevalencia de VIH , VIH-1 , Herpes Genital/epidemiología , Adulto , Atención Ambulatoria , Chancro/diagnóstico , Chancroide/diagnóstico , Distribución de Chi-Cuadrado , Femenino , Herpes Genital/diagnóstico , Humanos , Masculino , Valor Predictivo de las Pruebas , Atención Primaria de Salud , Rwanda/epidemiología , Sensibilidad y Especificidad , Estadísticas no Paramétricas
19.
Int J STD AIDS ; 5(5): 332-7, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7819350

RESUMEN

The aim of the study was to determine in a rural population the age- and sex-specific prevalence and incidence rates of serological reactivity of 5 common sexually transmitted diseases (STDs) and their association with HIV-1 antibody status. Of the adult population of two villages (529 adults aged 15 years or more) 294 provided an adequate blood specimen both on enrollment and at 12 months. The sera were tested at 3 collaborating laboratories for antibodies against HIV-1, Treponema pallidum, Haemophilus ducreyi, Chlamydia trachomatis and herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). A sample of 45 children were tested for HSV-1 and HSV-2. Seroprevalence rates in adults on enrollment were 7.8% for HIV-1, 10.8% for active syphilis, 10.4% for H. ducreyi, 66.0% for C. trachomatis, 91.2% for HSV-1 and 67.9% for HSV-2. Males were significantly more likely than females to be seropositive for H. ducreyi (15.6% versus 6.6%), but less likely to be HSV-2 antibody positive (57.0% versus 74.4%). Reactivity to H. ducreyi, C. trachomatis and HSV-2 rose with increasing age. In contrast, active syphilis showed no age trend. All STDs tended to be more common in those HIV-1 seropositive. Incidence rates over the 12 months were nil for HIV-1, 0.5% for syphilis, 1.2% for H. ducreyi, 11.3% for C. trachomatis, and 16.7% for HSV-2. The results of this exploratory study indicate that all STDs included are common in this rural population. The high HSV-2 prevalence rate among adolescents suggests that HSV-2 may be an important risk factor for HIV-1 infection.(ABSTRACT TRUNCATED AT 250 WORDS)


PIP: A seroprevalence survey conducted in rural Uganda revealed a high potential for interaction between sexually transmitted diseases (STDs) such as herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus (HIV). Venous blood samples were collected at baseline and one year later from 294 randomly selected adults aged 15 years or over from two neighboring villages. At baseline, 23 (7.8%) adults were HIV-positive; no seroconversion occurred during the one-year study period. STD prevalence rates were 10.8% for syphilis, 10.4% for Hemophilus ducreyi, 66.0% for Chlamydia trachomatis, and 91.2% for HSV-1 and 67.9% for HSV-2. More females (74.4%) than males (57.0%) were HSV-2 antibody-positive. Reactivity to H. ducreyi, C. trachomatis, and HSV-2 rose with increasing age, but there was no such trend for syphilis. HIV prevalence rates were 0.0% among those with no serologic evidence of previous STDs, 2.6% among those with one or two prior STDs, and 20.0% among those with three or four STD markers. Of particular concern was the high rate of HSV-2 prevalence among adolescents (85% among females aged 20-24 years and 82% in males aged 25-29 years). It is suggested that age-specific HSV-2 seroprevalence can provide an accurate marker of premarital sexual activity among Ugandan adolescents since it lacks the potential for bias associated with self-reporting in this population.


Asunto(s)
Seropositividad para VIH/epidemiología , Seroprevalencia de VIH , VIH-1 , Vigilancia de la Población , Población Rural , Enfermedades de Transmisión Sexual/epidemiología , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Comorbilidad , Femenino , Seropositividad para VIH/sangre , Seropositividad para VIH/complicaciones , Seropositividad para VIH/transmisión , Humanos , Incidencia , Lactante , Masculino , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Estudios Seroepidemiológicos , Factores Sexuales , Enfermedades de Transmisión Sexual/sangre , Enfermedades de Transmisión Sexual/complicaciones , Enfermedades de Transmisión Sexual/transmisión , Uganda/epidemiología
20.
Int J STD AIDS ; 8(10): 636-8, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9310223

RESUMEN

A cross-sectional survey was conducted among women attending an antenatal clinic in Abidjan to determine the prevalence of sexually transmitted diseases (STDs) and HIV infection, and to identify factors associated with the presence of gonococcal and/or chlamydial cervical infection. Among 546 women, 3.7% had a gonococcal infection and 5.5% had a chlamydial infection. The seroprevalence of syphilis and HIV was 1.1% and 16.2% respectively. Gonococcal and/or chlamydial cervical infection was associated with young age, the presence of endocervical mucopus and with more than 10 polymorphonuclear leucocytes per high power field in a vaginal smear. None of these associated factors had a large enough predictive value to allow its use as a diagnostic criterion. Sexually transmitted diseases are common in pregnant women in Abidjan. The development of rapid, inexpensive diagnostic tests for STD is a priority to improve the care of women attending antenatal clinics in the developing world.


Asunto(s)
Infecciones por VIH/complicaciones , Seroprevalencia de VIH , Complicaciones Infecciosas del Embarazo , Enfermedades de Transmisión Sexual/complicaciones , Adolescente , Adulto , Distribución por Edad , Côte d'Ivoire , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Atención Prenatal , Prevalencia , Salud Urbana , Frotis Vaginal
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