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1.
AIDS Res Hum Retroviruses ; 14 Suppl 1: S11-5, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9581878

RESUMEN

Heterosexual transmission is the predominant mode of transmission of HIV-1 in most of the world. Factors correlated with viral shedding from the female reproductive tract (and thus infectivity of women) are discussed in this review. Hormonal contraceptive use, cervical ectopy, pregnancy, abnormal cervical and vaginal discharge, and CD4 lymphocyte depletion have been associated with increased HIV-1 shedding in women; however, findings vary between studies. Prevalence and correlates of cervicovaginal HIV-1 shedding in larger published studies are discussed and potential mechanisms for observed associations are reviewed.


Asunto(s)
Genitales Femeninos/virología , VIH-1 , Esparcimiento de Virus/fisiología , Femenino , Infecciones por VIH/virología , Humanos , Embarazo
3.
J Biol Chem ; 270(47): 28193-8, 1995 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-7499312

RESUMEN

Profilaggrin, an insoluble precursor of the intermediate filament-associated protein filaggrin, contains multiple internal repeats (PIRs). At terminal differentiation of epidermis, proteolytic processing within a "linker" region of each PIR releases soluble filaggrin in a two-stage process. The first stage endoproteinase (PEP1, profilaggrin endoproteinase 1) cleaves mouse profilaggrin at a subset of the linkers, yielding processing intermediates consisting of several filaggrin repeats. An epidermal endoproteinase that cleaves the requisite linker subset has been purified 4,966-fold from mouse epidermal extracts. SDS-polyacrylamide gel electrophoresis demonstrated a band of molecular mass of 29.5 kDa that correlated with the activity. Labeling with [3H]diisopropylfluorophosphate identified PEP1 as a serine protease; inhibitor studies suggest that it is similar to chymotrypsin, as expected from previous in vivo studies. The purified PEP1 cleaved a peptide derived from profilaggrin (P1) at three residues within and adjacent to a multiple tyrosine sequence, consistent with the in vivo processing sites. No exopeptidase activity was detected. PEP1 is only active toward insoluble profilaggrin, resulting in partial solubilization, consistent with a role in dispersal of profilaggrin during terminal differentiation. In contrast to the specific cleavage of mouse profilaggrin, PEP1 cleaved all linker regions of rat profilaggrin. Studies with phosphorylated P1 suggest that PEP1 specificity may be partly regulated by profilaggrin phosphorylation.


Asunto(s)
Epidermis/enzimología , Proteínas de Filamentos Intermediarios/metabolismo , Precursores de Proteínas/metabolismo , Procesamiento Proteico-Postraduccional , Serina Endopeptidasas/metabolismo , Secuencia de Aminoácidos , Animales , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Proteínas Filagrina , Proteínas de Filamentos Intermediarios/química , Proteínas de Filamentos Intermediarios/aislamiento & purificación , Isoflurofato/metabolismo , Cinética , Ratones , Datos de Secuencia Molecular , Peso Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/metabolismo , Fosfoproteínas/aislamiento & purificación , Fosfoproteínas/metabolismo , Precursores de Proteínas/química , Precursores de Proteínas/aislamiento & purificación , Ratas , Homología de Secuencia de Aminoácido , Serina Endopeptidasas/aislamiento & purificación , Tirosina
4.
Biochem Biophys Res Commun ; 233(3): 681-6, 1997 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-9168914

RESUMEN

The stereochemistry of hydrogen transfer to NAD(P)+ has been determined for five lactol dehydrogenases. It was found that D-glucose dehydrogenases from Bacillus megaterium and Cryptococcus uniguttulatus and L-rhamnose dehydrogenase from Aureobasidium pullulans are pro-S (B) specific, while D-glucose dehydrogenase from Thermoplasma acidophilum and D-xylose dehydrogenase from procine liver are pro-R (A) specific. The latter two enzymes are the first examples of A-specific dehydrogenases oxidizing aldoses at the anomeric carbon. These findings are discussed in terms of functional and historical models that seek to make predictive generalizations regarding dehydrogenase stereospecificity.


Asunto(s)
Deshidrogenasas de Carbohidratos/metabolismo , Hidrógeno/metabolismo , NADP/metabolismo , NAD/metabolismo , Animales , Bacillus megaterium/enzimología , Cryptococcus/enzimología , Hígado/enzimología , Espectroscopía de Resonancia Magnética , Hongos Mitospóricos/enzimología , NAD/química , NADP/química , Estereoisomerismo , Especificidad por Sustrato , Porcinos , Thermoplasma/enzimología
5.
J Infect Dis ; 181(1): 58-63, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10608751

RESUMEN

Genital shedding of herpes simplex virus (HSV) results in frequent transmission of infection to sexual partners and neonates. In a cross-sectional study, cervical shedding of HSV DNA was detected in 43 (17%) cervical swab samples from 273 women seropositive for HSV-1, HSV-2, and human immunodeficiency virus type 1 (HIV-1). Cervical shedding of HSV was significantly associated with oral contraception (adjusted odds ratio [aOR], 4.5; 95% confidence interval [CI], 1.7-12.2), use of depo-medroxyprogesterone acetate (aOR, 3.2; 95% CI, 1.3-7.7), and pregnancy (aOR, 7.9; 95% CI, 2.0-31.7). In the subgroup of women who were not pregnant and not using hormonal contraception (n=178), serum vitamin A was highly predictive of cervical HSV shedding: concentrations indicating severe deficiency, moderate deficiency, low-normal, and high-normal status were associated with 29%, 18%, 8%, and 2% prevalences of cervical HSV shedding, respectively (linear trend, P=.0002). Several factors appear to influence HSV reactivation in HIV-1 seropositive women.


Asunto(s)
Cuello del Útero/virología , Anticonceptivos Hormonales Orales , Seropositividad para VIH/virología , VIH-1 , Herpes Simple/virología , Esparcimiento de Virus , Deficiencia de Vitamina A , Anticoncepción , Estudios Transversales , Femenino , Humanos , Kenia , Embarazo
6.
Am J Obstet Gynecol ; 183(4): 948-55, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11035345

RESUMEN

OBJECTIVE: Our purpose was to evaluate the frequency and patterns of the shedding of herpes simplex virus and cytomegalovirus in the female genital tract throughout the menstrual cycle. STUDY DESIGN: Seventeen women, all seropositive for herpes simplex virus types 1 and 2, cytomegalovirus, and human immunodeficiency virus type 1, underwent daily evaluation of cervical viral shedding for the duration of 1 menstrual cycle (21-31 visits per woman). Serum estradiol and progesterone levels were monitored 3 times weekly. RESULTS: Overall, herpes simplex virus deoxyribonucleic acid was detected in 43 (10%) of 450 cervical swabs, and cytomegalovirus deoxyribonucleic acid was detected in 232 (52%) of 450 cervical swabs. For individual women there was considerable variability in the percentage of days on which virus was detected, ranging from 0% to 33% for herpes simplex virus and from 20% to 97% for cytomegalovirus. Shedding of herpes simplex virus did not vary significantly with menstrual cycle; however, shedding of cytomegalovirus was significantly more frequent in the luteal phase (odds ratio, 1.9; 95% confidence interval, 1.1-3.4). A CD4(+) lymphocyte count <200/microL was associated with increased frequency of the detection of herpes simplex virus (odds ratio, 5.7; 95% confidence interval, 1.1-29.4). CONCLUSIONS: Asymptomatic cervical shedding of both herpes simplex virus and cytomegalovirus occurs very frequently in women infected with human immunodeficiency virus type 1. The risk of transmitting these viruses to sexual partners and neonates may be higher than previously recognized.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/virología , Cuello del Útero/virología , Citomegalovirus/fisiología , VIH-1 , Ciclo Menstrual , Simplexvirus/fisiología , Esparcimiento de Virus , Síndrome de Inmunodeficiencia Adquirida/fisiopatología , Adulto , Cuello del Útero/química , Citomegalovirus/genética , ADN Viral/análisis , Femenino , Humanos , Simplexvirus/genética
7.
J Infect Dis ; 178(4): 983-91, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9806025

RESUMEN

Cervical and vaginal secretions from 17 women infected with human immunodeficiency virus type 1 (HIV-1) were evaluated daily through the course of one menstrual cycle for HIV-1 DNA (21-31 visits per woman). HIV-1-infected cells were detected in 207 (46%) of 450 endocervical swabs and 74 (16%) of 449 vaginal swabs. There was considerable variability in the percentage of positive swabs from each woman, ranging from 4% to 100% of endocervical swabs and from 0 to 71% of vaginal swabs. In multivariate analyses, plasma HIV-1 RNA was significantly associated with shedding of HIV-1-infected cells; each 1-unit increase in the log of plasma virus load was associated with a 5.6-fold increase in the odds of cervical shedding (95% confidence interval [CI], 2.1-14.8) and a 3.9-fold increase in the odds of vaginal shedding (95% CI, 2.1-7.2). There was no discernible pattern of genital tract shedding with phase of the menstrual cycle and no significant association with serum estradiol or progesterone levels.


Asunto(s)
Genitales Femeninos/virología , Seropositividad para VIH/virología , VIH-1 , Ciclo Menstrual , Esparcimiento de Virus , Adulto , Cuello del Útero/virología , Femenino , Seropositividad para VIH/sangre , Humanos , Análisis Multivariante , Estudios Prospectivos , ARN Viral/sangre , Vagina/virología
8.
J Med Virol ; 59(4): 469-73, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10534728

RESUMEN

Cervical shedding of cytomegalovirus (CMV) is important in transmission of CMV to exposed sexual partners and neonates. We evaluated prevalence and correlates of CMV DNA shedding in cervical secretions from a large cohort of HIV-1-seropositive women. Using polymerase chain reaction (PCR) assays, CMV DNA was detected in 183 (59%) cervical swab samples from 311 women. Cervical shedding of CMV DNA was significantly associated with shedding of HIV-1 DNA (odds ratio 1.8; 95% confidence interval 1.1-2.8). CMV shedding was also more frequent in women with Neisseria gonorrhoeae and Trichomonas vaginalis infections, but these associations were not statistically significant. Cervical shedding of CMV in HIV-1-infected women is very frequent and may reflect higher risk of transmission to sexual partners and neonates than previously appreciated.


Asunto(s)
Cuello del Útero/virología , Infecciones por Citomegalovirus/virología , Citomegalovirus/fisiología , Infecciones por VIH/complicaciones , Esparcimiento de Virus , Adolescente , Adulto , Estudios de Cohortes , Citomegalovirus/aislamiento & purificación , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/transmisión , ADN Viral/aislamiento & purificación , Femenino , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , VIH-1/fisiología , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos
9.
Lancet ; 350(9082): 922-7, 1997 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-9314871

RESUMEN

BACKGROUND: Factors that influence shedding of HIV-1 infected cells in cervical and vaginal secretions may be important determinants of sexual and vertical transmission of the virus. We investigated whether hormonal contraceptive use, vitamin A deficiency, and other variables were risk factors for cervical and vaginal shedding of HIV-infected cells. METHODS: Between December, 1994, and April, 1996, women who attended a municipal sexually transmitted diseases (STDs) clinic in Mombasa, Kenya, and had previously tested positive for HIV-1, were invited to take part in our cross-sectional study. Cervical and vaginal secretions from 318 women were evaluated for the presence of HIV-1 infected cells by PCR amplification of gag DNA sequences. FINDINGS: HIV-1 infected cells were detected in 51% of endocervical and 14% of vaginal-swab specimens. Both cervical and vaginal shedding of HIV-1 infected cells were highly associated with CD4 lymphocyte depletion (p = 0.00001 and p = 0.003, respectively). After adjustment for CD4 count, cervical proviral shedding was significantly associated with use of depot medroxyprogesterone acetate (odds ratio 2.9, 95% CI 1.5-5.7), and with use of low-dose and high-dose oral contraceptive pills (3.8, 1.4-9.9 and 12.3, 1.5-101, respectively). Vitamin A deficiency was highly predictive of vaginal HIV-1 DNA shedding. After adjustment for CD4 count, severe vitamin A deficiency, moderate deficiency, and low normal vitamin A status were associated with 12.9, 8.0, and 4.9-fold increased odds of vaginal shedding, respectively. Gonococcal cervicitis (3.1, 1.1-9.8) and vaginal candidiasis (2.6, 1.2-5.4) were also correlated with significant increases in HIV-1 DNA detection, but Chlamydia trachomatis and Trichomonas vaginalis were not. INTERPRETATION: Our study documents several novel correlates of HIV-1 shedding in cervical and vaginal secretions, most notably hormonal contraceptive use and vitamin A deficiency. These factors may be important determinants of sexual or vertical transmission of HIV-1 and are of public health importance because they are easily modified by simple interventions.


PIP: Correlates of HIV-1 shedding in cervical and vaginal secretions were investigated in a cross-sectional study of 318 women previously diagnosed with HIV who presented to a sexually transmitted disease clinic in Mombasa, Kenya, during 1994-96. HIV-infected cells were detected in 51% of endocervical and 14% of vaginal swab specimens. Both cervical and vaginal shedding of HIV-1 infected cells were highly associated with CD4 lymphocyte depletion. After adjustment for CD4 count, cervical proviral shedding was significantly associated with use of depo medroxyprogesterone acetate (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.5-5.7) and of low- and high-dose oral contraceptives (OR, 3.8; 95% CI, 1.4-9.9 and OR, 12.3; 95% CI, 1.5-101, respectively). After adjustment for CD4 count, severe vitamin A deficiency, moderate deficiency, and low-normal vitamin A status were associated with 12.9, 8.0, and 4.9-fold increased odds of vaginal shedding, respectively. Finally, gonococcal cervicitis (OR, 3.1; 95% CI, 1.1-9.8) and vaginal candidiasis (OR, 2.6; 95% CI, 1.2-5.4), but not Chlamydia trachomatis and Trichomonas vaginalis, were correlated with significant increases in HIV-1 DNA detection. These risk factors, easily modifiable by simple interventions, may be important determinants of sexual or vertical HIV transmission.


Asunto(s)
Cuello del Útero/virología , Anticonceptivos Hormonales Orales/farmacología , ADN Viral/aislamiento & purificación , Infecciones por VIH/transmisión , VIH-1/aislamiento & purificación , Vagina/virología , Deficiencia de Vitamina A/virología , Adolescente , Adulto , Cuello del Útero/efectos de los fármacos , Estudios Transversales , Femenino , Seropositividad para VIH , VIH-1/inmunología , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Kenia , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Factores de Riesgo , Enfermedades Bacterianas de Transmisión Sexual/diagnóstico , Vagina/efectos de los fármacos
10.
J Acquir Immune Defic Syndr ; 26(4): 360-4, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11317079

RESUMEN

OBJECTIVE: To assess the relation between selenium deficiency and vaginal or cervical shedding of HIV-1-infected cells. DESIGN: Cross-sectional study of 318 HIV-1 seropositive women in Mombasa, Kenya. METHODS: Vaginal and cervical swab specimens were tested for the presence of HIV-1 DNA by polymerase chain reaction. Multivariate logistic regression models, adjusting for CD4 count and vitamin A deficiency, were used. RESULTS: Selenium deficiency (defined as levels <85 microg/L) was observed in 11% of the study population. In unstratified multivariate analyses, there was no significant association between selenium deficiency and vaginal or cervical shedding. In stratified analyses, however, significant associations became apparent after excluding women with predictors of shedding with strong local effects on the genital tract mucosa. Among women who did not use oral contraceptives and who did not have vaginal candidiasis, selenium deficiency was significantly associated with vaginal shedding (adjusted odds ratio [AOR] 2.9, 95% confidence interval [CI] 1.0--8.8, p =.05). Effect modification was also observed in the relation between selenium deficiency and cervical shedding, with a significant association seen among those women who were not using oral contraceptive pills or depot medroxyprogesterone acetate and who did not have Neisseria gonorrhoeae infection (AOR 2.8, 95% CI 1.1--7.0, p =.02). CONCLUSIONS: We found selenium deficiency to be associated with a nearly threefold higher likelihood of genital mucosal shedding of HIV-1--infected cells, suggesting that deficiency may increase the infectiousness of women with HIV-1. Nutritional interventions to prevent HIV-1 transmission warrant investigation.


Asunto(s)
Cuello del Útero/virología , Infecciones por VIH/transmisión , Infecciones por VIH/virología , VIH-1/fisiología , Selenio/deficiencia , Vagina/virología , Esparcimiento de Virus , Adolescente , Adulto , Recuento de Linfocito CD4 , Cuello del Útero/patología , Estudios Transversales , ADN Viral/análisis , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/patología , VIH-1/genética , Humanos , Kenia , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Selenio/sangre , Vagina/patología , Deficiencia de Vitamina A/sangre , Deficiencia de Vitamina A/virología , Vitamina E/sangre
11.
J Infect Dis ; 179 Suppl 3: S401-4, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10099106

RESUMEN

If human immunodeficiency virus type 1 (HIV-1) vaccines are to be highly effective, it is essential to understand the virologic factors that contribute to HIV-1 transmission. It is likely that transmission is determined, in part, by the genotype or phenotype (or both) of infectious virus present in the index case, which in turn will influence the quantity of virus that may be exchanged during sexual contact. Transmission may also depend on the fitness of the virus for replication in the exposed individual, which may be influenced by whether a virus encounters a target cell that is susceptible to infection by that specific variant. Of interest, our data suggest that the complexity of the virus that is transmitted may be different in female and male sexual exposures.


Asunto(s)
Brotes de Enfermedades , Infecciones por VIH/transmisión , Infecciones por VIH/virología , VIH-1 , Esparcimiento de Virus , Adulto , Lactancia Materna , Femenino , Genotipo , Infecciones por VIH/epidemiología , Infecciones por VIH/genética , VIH-1/clasificación , VIH-1/genética , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Kenia/epidemiología , Masculino
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