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1.
Nucleic Acids Res ; 50(3): 1650-1660, 2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35051997

RESUMEN

The Cas9 nuclease from Staphylococcus aureus (SaCas9) holds great potential for use in gene therapy, and variants with increased fidelity have been engineered. However, we find that existing variants have not reached the greatest accuracy to discriminate base mismatches and exhibited much reduced activity when their mutations were grafted onto the KKH mutant of SaCas9 for editing an expanded set of DNA targets. We performed structure-guided combinatorial mutagenesis to re-engineer KKH-SaCas9 with enhanced accuracy. We uncover that introducing a Y239H mutation on KKH-SaCas9's REC domain substantially reduces off-target edits while retaining high on-target activity when added to a set of mutations on REC and RuvC domains that lessen its interactions with the target DNA strand. The Y239H mutation is modelled to have removed an interaction from the REC domain with the guide RNA backbone in the guide RNA-DNA heteroduplex structure. We further confirmed the greatly improved genome-wide editing accuracy and single-base mismatch discrimination of our engineered variants, named KKH-SaCas9-SAV1 and SAV2, in human cells. In addition to generating broadly useful KKH-SaCas9 variants with unprecedented accuracy, our findings demonstrate the feasibility for multi-domain combinatorial mutagenesis on SaCas9's DNA- and guide RNA- interacting residues to optimize its editing fidelity.


Asunto(s)
Proteína 9 Asociada a CRISPR/genética , Edición Génica , Staphylococcus aureus , Sistemas CRISPR-Cas , Humanos , Nucleasa Microcócica/genética , ARN Guía de Kinetoplastida , Staphylococcus aureus/genética
2.
BMC Med Res Methodol ; 22(1): 64, 2022 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-35249528

RESUMEN

BACKGROUND: With advances in cancer diagnosis and treatment, women with early-stage breast cancer (ESBC) are living longer, increasing the number of patients receiving post-treatment follow-up care. Best-practice survivorship models recommend transitioning ESBC patients from oncology-provider (OP) care to community-based care. While developing materials for a future randomized controlled trial (RCT) to test the feasibility of a nurse-led Telephone Survivorship Clinic (TSC) for a smooth transition of ESBC survivors to follow-up care, we explored patients' and OPs' reactions to several of our proposed methods. METHODS: We used a qualitative study design with thematic analysis and a two-pronged approach. We interviewed OPs, seeking feedback on ways to recruit their ESBC patients for the trial, and ESBC patients, seeking input on a questionnaire package assessing outcomes and processes in the trial. RESULTS: OPs identified facilitators and barriers and offered suggestions for study design and recruitment process improvement. Facilitators included the novelty and utility of the study and simplicity of methods; barriers included lack of coordination between treating and discharging clinicians, time constraints, language barriers, motivation, and using a paper-based referral letter. OPs suggested using a combination of electronic and paper referral letters and supporting clinicians to help with recruitment. Patient advisors reported satisfaction with the content and length of the assessment package. However, they questioned the relevance of some questions (childhood trauma) while adding questions about trust in physicians and proximity to primary-care providers. CONCLUSIONS: OPs and patient advisors rated our methods for the proposed trial highly for their simplicity and relevance then suggested changes. These findings document processes that could be effective for cancer-patient recruitment in survivorship clinical trials.


Asunto(s)
Neoplasias de la Mama , Sobrevivientes , Cuidados Posteriores , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Femenino , Humanos , Oncología Médica , Encuestas y Cuestionarios
3.
PLoS Pathog ; 14(1): e1006754, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29346424

RESUMEN

In the majority of cases, human immunodeficiency virus type 1 (HIV-1) infection is transmitted through sexual intercourse. A single founder virus in the blood of the newly infected donor emerges from a genetic bottleneck, while in rarer instances multiple viruses are responsible for systemic infection. We sought to characterize the sequence diversity at early infection, between two distinct anatomical sites; the female reproductive tract vs. systemic compartment. We recruited 72 women from Uganda and Zimbabwe within seven months of HIV-1 infection. Using next generation deep sequencing, we analyzed the total genetic diversity within the C2-V3-C3 envelope region of HIV-1 isolated from the female genital tract at early infection and compared this to the diversity of HIV-1 in plasma. We then compared intra-patient viral diversity in matched cervical and blood samples with three or seven months post infection. Genetic analysis of the C2-V3-C3 region of HIV-1 env revealed that early HIV-1 isolates within blood displayed a more homogeneous genotype (mean 1.67 clones, range 1-5 clones) than clones in the female genital tract (mean 5.7 clones, range 3-10 clones) (p<0.0001). The higher env diversity observed within the genital tract compared to plasma was independent of HIV-1 subtype (A, C and D). Our analysis of early mucosal infections in women revealed high HIV-1 diversity in the vaginal tract but few transmitted clones in the blood. These novel in vivo finding suggest a possible mucosal sieve effect, leading to the establishment of a homogenous systemic infection.


Asunto(s)
Cuello del Útero/virología , Variación Genética , Infecciones por VIH/virología , Seropositividad para VIH/virología , VIH-1/genética , Vagina/virología , Viremia/virología , Secuencia de Bases , Estudios de Cohortes , Femenino , Seropositividad para VIH/sangre , VIH-1/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Estudios Longitudinales , ARN Viral/sangre , ARN Viral/química , ARN Viral/aislamiento & purificación , Infecciones del Sistema Genital/sangre , Infecciones del Sistema Genital/virología , Uganda , Carga Viral , Viremia/sangre , Zimbabwe , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
4.
PLoS Med ; 15(2): e1002511, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29485986

RESUMEN

BACKGROUND: Estimates of sexually transmitted infection (STI) prevalence are essential for efforts to prevent and control STIs. Few large STI prevalence studies exist, especially for low- and middle-income countries (LMICs). Our primary objective was to estimate the prevalence of chlamydia, gonorrhea, trichomoniasis, syphilis, herpes simplex virus type 2 (HSV-2), and bacterial vaginosis (BV) among women in sub-Saharan Africa by age, region, and population type. METHODS AND FINDINGS: We analyzed individual-level data from 18 HIV prevention studies (cohort studies and randomized controlled trials; conducted during 1993-2011), representing >37,000 women, that tested participants for ≥1 selected STIs or BV at baseline. We used a 2-stage meta-analysis to combine data. After calculating the proportion of participants with each infection and standard error by study, we used a random-effects model to obtain a summary mean prevalence of each infection and 95% confidence interval (CI) across ages, regions, and population types. Despite substantial study heterogeneity for some STIs/populations, several patterns emerged. Across the three primary region/population groups (South Africa community-based, Southern/Eastern Africa community-based, and Eastern Africa higher-risk), prevalence was higher among 15-24-year-old than 25-49-year-old women for all STIs except HSV-2. In general, higher-risk populations had greater prevalence of gonorrhea and syphilis than clinic/community-based populations. For chlamydia, prevalence among 15-24-year-olds was 10.3% (95% CI: 7.4%, 14.1%; I2 = 75.7%) among women specifically recruited from higher-risk settings for HIV in Eastern Africa and was 15.1% (95% CI: 12.7%, 17.8%; I2 = 82.3%) in South African clinic/community-based populations. Among clinic/community-based populations, prevalence was generally greater in South Africa than in Southern/Eastern Africa for most STIs; for gonorrhea, prevalence among 15-24-year-olds was 4.6% (95% CI: 3.3%, 6.4%; I2 = 82.8%) in South Africa and was 1.7% (95% CI: 1.2%, 2.6%; I2 = 55.2%) in Southern/Eastern Africa. Across the three primary region/population groups, HSV-2 and BV prevalence was high among 25-49-year-olds (ranging from 70% to 83% and 33% to 44%, respectively). The main study limitation is that the data are not from random samples of the target populations. CONCLUSIONS: Combining data from 18 HIV prevention studies, our findings highlight important features of STI/BV epidemiology among sub-Saharan African women. This methodology can be used where routine STI surveillance is limited and offers a new approach to obtaining critical information on STI and BV prevalence in LMICs.


Asunto(s)
Infecciones por VIH/prevención & control , Enfermedades de Transmisión Sexual/epidemiología , Vaginosis Bacteriana/epidemiología , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Femenino , VIH , Infecciones por VIH/epidemiología , Promoción de la Salud/métodos , Promoción de la Salud/organización & administración , Promoción de la Salud/normas , Humanos , Persona de Mediana Edad , Prevalencia , Adulto Joven
6.
Paediatr Child Health ; 23(5): e77-e84, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30046272

RESUMEN

PURPOSE: Early childhood experiences of poverty are associated with adverse developmental outcomes that have impli cations for individual and population health. Low educational attainment and early childbearing are two such important outcomes that can perpetuate childhood poverty into adulthood. Child hunger, or severe food insecurity, is an extreme manifestation of household food insecurity that is associated with the stressful experience of deep family poverty. Life-course theories suggest that childhood experiences of hunger could have adverse effects in the developmental pathway. The objective of this study was to examine the independent contribution of the child hunger experience to subsequent educational attainment and early childbearing in young adult men and women, in consideration of other latent, cumulative or shock effects associated with child poverty. METHODS: We analyzed National Longitudinal Survey of Children and Youth data using logistic regression based on 15,468 Canadian children followed over 16 years. RESULTS: The prevalence of the experience of child hunger was 5.0%. Child hunger was independently predictive of youth leaving high school, yet was not a factor in the achievement of higher educational attainment if youth were able to graduate from high school. Having always lived in rental accommodation and repeated reports of child hunger over time were predictive of early childbearing. CONCLUSIONS: Interventions directed at children and youth who are at risk of poor developmental outcomes because of severe food insecurity should focus on steering families toward their income entitlements, and providing support for youth to complete high school and to avoid early fertility.

7.
Soc Psychiatry Psychiatr Epidemiol ; 52(5): 537-547, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28285453

RESUMEN

PURPOSE: We used longitudinal data to clarify the association between self-report of hunger and subsequent depression risk among youth and young adults, accounting for other risk factors. METHODS: Youth self-report of ever experiencing hunger data were collected from cycles 4-6 of the National Longitudinal Survey of Children and Youth cohort of Canadian youth 16 years and older (n = 4139). Data on depressive symptoms (CES-D 12) were collected over three cycles (2004-2009, cycles 6-8). We used multivariable regression based on generalized estimating equations (GEE) to examine prior youth hunger on later depression risk, adjusting for time-stable, time-varying, and lagged variables (e.g., depressive symptoms in previous cycle), thereby clarifying the temporal relationship. RESULTS: The prevalence of youth hunger experience and depression risk reached 5.9 and 15.0%, respectively. The adjusted odds ratio of depression for participants reporting hunger was 2.31 (95% CI 1.54, 3.46) and changed little [2.17 (95% CI 1.29, 3.67)] after accounting for previous CES-D 12 scores, suggesting a temporal relationship in which hunger contributes to depression risk. Unlike never-hungry youth, depression in ever-hungry youth remained comparatively elevated over time. CONCLUSIONS: Our models support an independent and temporal relationship between youth self-report of hunger and depression in adolescence and young adulthood.


Asunto(s)
Depresión/psicología , Hambre , Autoinforme , Adolescente , Canadá , Niño , Depresión/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Análisis Multivariante , Oportunidad Relativa , Prevalencia , Análisis de Regresión , Factores de Riesgo , Adulto Joven
8.
Am J Obstet Gynecol ; 215(3): 332.e1-332.e10, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26945606

RESUMEN

BACKGROUND: Bacterial vaginosis, a highly prevalent vaginal condition, is correlated with many adverse reproductive outcomes. In some studies, low vitamin D status (measured as serum 25-hydroxyvitamin D, 25[OH]D) has been associated with increased prevalence of bacterial vaginosis. OBJECTIVES: We examined the cross-sectional association between vitamin D status and prevalence of bacterial vaginosis, separately for pregnant and nonpregnant women. Using prospectively collected data, we also characterized the effect of time-varying vitamin D status on incident bacterial vaginosis. STUDY DESIGN: We quantified 25(OH)D in stored sera collected quarterly from 571 Zimbabwean women participating in the Hormonal Contraception and Risk of HIV Acquisition Study. The analysis was restricted to women not using hormonal contraception. We characterized associations between vitamin D insufficiency (defined as 25[OH]D ≤ 30 ng/mL vs > 30 ng/mL) and prevalence of bacterial vaginosis among nonpregnant women at the enrollment visit and among pregnant women at the first follow-up visit that pregnancy was detected. Among women who were negative for bacterial vaginosis at enrollment (n = 380), we also assessed the effect of time-varying vitamin D status on incident bacterial vaginosis. We used the Liaison 25(OH)D total assay to measure 25(OH)D. Bacterial vaginosis was diagnosed via Nugent score. RESULTS: At enrollment, the prevalence of bacterial vaginosis was 31% and overall median 25(OH)D was 29.80 ng/mL (interquartile range, 24.70-34.30 ng/mL): 29.75 ng/mL (interquartile range, 25.15-33.95 ng/mL) among women with bacterial vaginosis, and 29.90 ng/mL (interquartile range, 24.70-34.50 ng/mL) among women without bacterial vaginosis. Among pregnant women, the prevalence of bacterial vaginosis was 27% and overall median 25(OH)D was 29.90 ng/mL (interquartile range, 24.10-34.00 ng/mL): 30.80 ng/mL (interquartile range, 26.10-36.90 ng/mL) among women with bacterial vaginosis, and 29.10 ng/mL (interquartile range, 23.80-33.45 ng/mL) among women without bacterial vaginosis. Vitamin D levels ≤ 30 ng/mL were not associated with a prevalence of bacterial vaginosis in nonpregnant women (adjusted prevalence ratio, 1.04; 95% confidence interval, 0.81-1.34) or pregnant women (adjusted prevalence ratio, 0.88, 95% confidence interval, 0.51-1.54). Vitamin D levels ≤ 30 ng/mL were similarly not associated with incident bacterial vaginosis (adjusted hazard ratio, 0.98, 95% confidence interval, 0.73-1.31). Our findings were robust to alternative specifications of vitamin D status including using a cut point for vitamin D deficiency of < 20 ng/mL vs ≥ 20 ng/mL and modeling 25(OH)D as a continuous variable. CONCLUSION: Among reproductive-age Zimbabwean women, insufficient vitamin D was not associated with increased bacterial vaginosis prevalence or incidence. Given established associations between bacterial vaginosis and poor reproductive outcomes, identification of factors leading to high bacterial vaginosis prevalence is urgently needed.


Asunto(s)
Vaginosis Bacteriana/epidemiología , Deficiencia de Vitamina D/epidemiología , Vitamina D/análogos & derivados , Adulto , Comorbilidad , Femenino , Humanos , Incidencia , Prevalencia , Vaginosis Bacteriana/sangre , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Adulto Joven , Zimbabwe/epidemiología
9.
Am J Phys Anthropol ; 159(2): 284-99, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26481114

RESUMEN

OBJECTIVE: This study analyzes deciduous dental pathology and stable isotopes to investigate the relationship between diet, feeding practices, and oral health in a subadult skeletal sample from the Greek colonial site of Apollonia Pontica, Bulgaria (mid-5th to mid-3rd Centuries BC). METHODS: Stable carbon and nitrogen isotope analysis was conducted on 74 bone collagen samples, and the deciduous dentitions of 85 individuals aged 8.5 months to 11 years were examined for evidence of caries, calculus, antemortem tooth loss, abscesses, and occlusal tooth wear. RESULTS: δ(13) C and δ(15) N values of the collagen samples indicate that weaning began between the ages of 6 months and 1 year, and was complete for most individuals by the age of 3. The isotopic data are consistent with a mixed diet of primarily terrestrial C3 resources. The dental pathology data indicate that complementary foods provided to young children had an impact on their oral health early on. Four outliers exhibited elevated δ(15) N values compared with the adult female range and lower levels of tooth wear than other members of their age groups. Possible explanations include prolonged breastfeeding, the consumption of diets elevated in (15) N, and physiological/nutritional stress. CONCLUSIONS: The deciduous dental data correlate well with the isotopic data and are consistent with later textual sources regarding the timing and duration of weaning, and the composition of complementary foods. The results of this research demonstrate the value of combining isotopic and dental evidence to investigate the dietary practices of infants and young children and the impact of these practices on oral health.


Asunto(s)
Lactancia Materna , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Diente Primario/química , Adulto , Antropología Física , Lactancia Materna/historia , Bulgaria , Entierro , Niño , Preescolar , Conducta Alimentaria , Femenino , Historia Antigua , Historia Medieval , Humanos , Lactante , Costillas/química , Enfermedades Dentales/epidemiología , Enfermedades Dentales/historia
10.
PLoS Med ; 12(1): e1001778, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25612136

RESUMEN

BACKGROUND: Observational studies of a putative association between hormonal contraception (HC) and HIV acquisition have produced conflicting results. We conducted an individual participant data (IPD) meta-analysis of studies from sub-Saharan Africa to compare the incidence of HIV infection in women using combined oral contraceptives (COCs) or the injectable progestins depot-medroxyprogesterone acetate (DMPA) or norethisterone enanthate (NET-EN) with women not using HC. METHODS AND FINDINGS: Eligible studies measured HC exposure and incident HIV infection prospectively using standardized measures, enrolled women aged 15-49 y, recorded ≥15 incident HIV infections, and measured prespecified covariates. Our primary analysis estimated the adjusted hazard ratio (aHR) using two-stage random effects meta-analysis, controlling for region, marital status, age, number of sex partners, and condom use. We included 18 studies, including 37,124 women (43,613 woman-years) and 1,830 incident HIV infections. Relative to no HC use, the aHR for HIV acquisition was 1.50 (95% CI 1.24-1.83) for DMPA use, 1.24 (95% CI 0.84-1.82) for NET-EN use, and 1.03 (95% CI 0.88-1.20) for COC use. Between-study heterogeneity was mild (I(2) < 50%). DMPA use was associated with increased HIV acquisition compared with COC use (aHR 1.43, 95% CI 1.23-1.67) and NET-EN use (aHR 1.32, 95% CI 1.08-1.61). Effect estimates were attenuated for studies at lower risk of methodological bias (compared with no HC use, aHR for DMPA use 1.22, 95% CI 0.99-1.50; for NET-EN use 0.67, 95% CI 0.47-0.96; and for COC use 0.91, 95% CI 0.73-1.41) compared to those at higher risk of bias (p(interaction) = 0.003). Neither age nor herpes simplex virus type 2 infection status modified the HC-HIV relationship. CONCLUSIONS: This IPD meta-analysis found no evidence that COC or NET-EN use increases women's risk of HIV but adds to the evidence that DMPA may increase HIV risk, underscoring the need for additional safe and effective contraceptive options for women at high HIV risk. A randomized controlled trial would provide more definitive evidence about the effects of hormonal contraception, particularly DMPA, on HIV risk.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Infecciones por VIH/epidemiología , Acetato de Medroxiprogesterona/administración & dosificación , Noretindrona/análogos & derivados , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Anticonceptivos Femeninos/efectos adversos , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Humanos , Incidencia , Acetato de Medroxiprogesterona/efectos adversos , Persona de Mediana Edad , Noretindrona/administración & dosificación , Noretindrona/efectos adversos , Factores de Riesgo
11.
J Infect Dis ; 203(8): 1182-91, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21451006

RESUMEN

BACKGROUND: Individuals who acquire human immunodeficiency virus (HIV) may experience an immediate disruption of genital tract immunity, altering the ability to mount a local and effective immune response. This study examined the impact of early HIV infection on new detection of human papillomavirus (HPV). METHODS: One hundred fifty-five Zimbabwean women with observation periods before and after HIV acquisition and 486 HIV-uninfected women were selected from a cohort study evaluating hormonal contraceptive use and risk of HIV acquisition. Study visits occurred at 3-month intervals. Cervical swab samples available from up to 6 months before, at, and up to 6 months after the visit when HIV was first detected were typed for 37 HPV genotypes or subtypes. RESULTS: We observed ∼5-fold higher odds of multiple (≥2) new HPV detections only after HIV acquisition, relative to HIV-negative women after adjusting for sexual behavior and concurrent genital tract infections. We also observed ∼2.5-fold higher odds of single new HPV detections at visits before and after HIV acquisition, relative to HIV-uninfected women in multivariable models. CONCLUSIONS: These findings suggest that HIV infection has an immediate impact on genital tract immunity, as evidenced by the high risk of multiple new HPV detections immediately after HIV acquisition.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Adolescente , Adulto , Linfocitos T CD4-Positivos , Estudios de Cohortes , Femenino , Humanos , Adulto Joven , Zimbabwe/epidemiología
12.
Nat Commun ; 13(1): 2219, 2022 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-35468907

RESUMEN

The genome-editing Cas9 protein uses multiple amino-acid residues to bind the target DNA. Considering only the residues in proximity to the target DNA as potential sites to optimise Cas9's activity, the number of combinatorial variants to screen through is too massive for a wet-lab experiment. Here we generate and cross-validate ten in silico and experimental datasets of multi-domain combinatorial mutagenesis libraries for Cas9 engineering, and demonstrate that a machine learning-coupled engineering approach reduces the experimental screening burden by as high as 95% while enriching top-performing variants by ∼7.5-fold in comparison to the null model. Using this approach and followed by structure-guided engineering, we identify the N888R/A889Q variant conferring increased editing activity on the protospacer adjacent motif-relaxed KKH variant of Cas9 nuclease from Staphylococcus aureus (KKH-SaCas9) and its derived base editor in human cells. Our work validates a readily applicable workflow to enable resource-efficient high-throughput engineering of genome editor's activity.


Asunto(s)
Proteínas Bacterianas , Sistemas CRISPR-Cas , Proteínas Bacterianas/metabolismo , Sistemas CRISPR-Cas/genética , ADN/metabolismo , Humanos , Aprendizaje Automático , Mutagénesis
13.
PLoS One ; 15(1): e0224359, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31914129

RESUMEN

Sexually transmitted infections (STIs) and vaginal dysbiosis (disturbed resident microbiota presenting with abnormal Nugent score or candidiasis) have been associated with mucosal inflammation and risk of HIV-1 infection, cancer and poor reproductive outcomes. To date, the temporal relationships between aberrant cervical innate immunity and the clinical onset of microbial disturbance have not been studied in a large population of reproductive age women. We examined data from a longitudinal cohort of 934 Ugandan and Zimbabwean women contributing 3,274 HIV-negative visits who had complete laboratory, clinical and demographic data. Among those, 207 women later acquired HIV, and 584 women were intermittently diagnosed with C. trachomatis (CT), N. gonorrhoeae (NG), genital herpes (HSV-2), T. vaginalis (TV), candidiasis, and abnormal intermediate (4-6) or high (7-10) Nugent score, i.e. bacterial vaginosis (BV). Immune biomarker concentrations in cervical swabs were analyzed by generalized linear and mixed effect models adjusting for site, age, hormonal contraceptive use (HC), pregnancy, breastfeeding, genital practices, unprotected sex and overlapping infections. High likelihood ratios (1.5-4.9) denoted the values of cervical immune biomarkers to predict onset of abnormal Nugent score and candidiasis at the next visits. When controlling for covariates, higher levels of ß-defensin-2 were antecedent to BV, CT and HSV-2, lower anti-inflammatory ratio IL-1RA:IL-1ß-to intermediate Nugent scores and candida, lower levels of the serine protease inhibitor SLPI-to candida, lower levels of the adhesion molecule ICAM-1 -to TV, and lower levels of the oxidative stress mitigator and endothelial activation marker VEGF-to NG. Changes in innate immunity following onset of dysbiosis and infections were dependent on HC use when controlling for all other covariates. In conclusion, imminent female genital tract dysbiosis or infection can be predicted by distinct patterns of innate immunity. Future research should characterize biotic and abiotic determinants of this pre-existing innate immunity state.


Asunto(s)
Disbiosis/inmunología , Inmunidad Innata/genética , Enfermedades de Transmisión Sexual/inmunología , Vaginosis Bacteriana/inmunología , Adolescente , Adulto , Biomarcadores/metabolismo , Cuello del Útero/inmunología , Cuello del Útero/microbiología , Cuello del Útero/patología , Disbiosis/epidemiología , Disbiosis/microbiología , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Molécula 1 de Adhesión Intercelular/inmunología , Molécula 1 de Adhesión Intercelular/metabolismo , Proteína Antagonista del Receptor de Interleucina 1/inmunología , Proteína Antagonista del Receptor de Interleucina 1/metabolismo , Interleucina-1beta/inmunología , Interleucina-1beta/metabolismo , Estrés Oxidativo/inmunología , Embarazo , Infecciones del Sistema Genital/epidemiología , Infecciones del Sistema Genital/inmunología , Inhibidor Secretorio de Peptidasas Leucocitarias/inmunología , Inhibidor Secretorio de Peptidasas Leucocitarias/metabolismo , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/microbiología , Uganda/epidemiología , Vagina/inmunología , Vagina/microbiología , Vaginosis Bacteriana/epidemiología , Vaginosis Bacteriana/microbiología , Factor A de Crecimiento Endotelial Vascular/inmunología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Zimbabwe/epidemiología
14.
Sex Transm Dis ; 36(6): 357-64, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19434010

RESUMEN

OBJECTIVE: : To estimate the effects of reproductive tract infections (RTIs) on HIV acquisition among Zimbabwean and Ugandan women. METHODS: : A multicenter prospective observational cohort study enrolled 4439 HIV-uninfected women aged 18 to 35 attending family planning clinics in Zimbabwe and Uganda. Participants were interviewed, and tested for HIV and RTIs every 3 months for 15 to 24 months. They received HIV risk reduction counseling, male condoms, and treatment for curable RTIs. RESULTS: : Despite HIV risk reduction counseling and regular screening and treatment for RTIs, the HIV incidence did not decline during the study. Positive HSV-2 serostatus at baseline (hazard ratio [HR] = 3.69, 95% confidence interval = 2.45-5.55), incident HSV-2 (HR = 5.35, 3.06-9.36), incident Neisseria gonorrhoeae (HR = 5.46, 3.41-8.75), and altered vaginal flora during the study (bacterial vaginosis [BV]: HR = 2.12, 1.50-3.01; and intermediate flora: HR = 2.02, 1.39-2.95) were independently associated with HIV acquisition after controlling for demographic and behavioral covariates and other RTIs (Treponema pallidum, Chlamydia trachomatis, Trichomonas vaginalis, and vaginal yeasts). For N. gonorrhoeae, C. trachomatis, T. vaginalis, and vaginal yeasts, the risk of HIV acquisition increased when the infection was identified at the visit before the HIV-detection visit or with the duration of infection. Population attributable risk percent (PAR%) calculations show that HSV-2 contributes most to acquisition of new HIV infections (50.4% for baseline HSV-2 and 7.9% for incident HSV-2), followed by altered vaginal flora (17.2% for bacterial vaginosis and 11.8% for intermediate flora). CONCLUSIONS: : A substantial proportion of new HIV infections in Zimbabwean and Ugandan women are attributable to RTIs, particularly HSV-2 and altered vaginal flora.


Asunto(s)
Infecciones por VIH/epidemiología , Enfermedades de Transmisión Sexual/complicaciones , Adolescente , Adulto , Estudios de Cohortes , Femenino , Infecciones por VIH/etiología , Herpes Genital/complicaciones , Herpesvirus Humano 2 , Humanos , Incidencia , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Uganda/epidemiología , Vagina/microbiología , Vagina/virología , Adulto Joven , Zimbabwe/epidemiología
15.
Contraception ; 77(6): 410-4, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18477489

RESUMEN

BACKGROUND: Progestin-only injectable contraceptives continue to gain in popularity, but uncertainty remains about pregnancy risk among women late for reinjection. The World Health Organization (WHO) recommends a "grace period" of 2 weeks after the scheduled 13-week reinjection. Beyond 2 weeks, however, many providers send late clients home to await menses. STUDY DESIGN: A prospective cohort study in Uganda, Zimbabwe and Thailand followed users of depot-medroxyprogesterone acetate (DMPA) for up to 24 months. Users were tested for pregnancy at every reinjection, allowing analysis of pregnancy risk among late comers. RESULTS: The analysis consists of 2290 participants contributing 13,608 DMPA intervals. The pregnancy risks per 100 women-years for "on time" [0.6; 95% confidence interval (CI), 0.33-0.92], "2-week grace" (0.0; 95% CI, 0.0-1.88) and "4-week grace" (0.4; 95% CI, 0.01-2.29) injections were low and virtually identical. CONCLUSION: Extending the current WHO grace period for DMPA reinjection from 2 to 4 weeks does not increase pregnancy risk and could increase contraceptive continuation.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Medroxiprogesterona/administración & dosificación , Índice de Embarazo , Adulto , Estudios de Cohortes , Conducta Anticonceptiva , Esquema de Medicación , Femenino , Humanos , Inyecciones Intramusculares , Embarazo , Estudios Prospectivos , Tailandia , Resultado del Tratamiento , Uganda , Zimbabwe
16.
AIDS Res Hum Retroviruses ; 34(10): 889-899, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30047279

RESUMEN

Hormonal contraception (HC), particularly injectable depot-medroxyprogesterone acetate (DMPA), has been associated with increased HIV acquisition and higher levels of cervical regulated upon activation, normal T-cell expressed, and secreted (RANTES), also associated with HIV seroconversion. Longitudinal changes in cervical immunity associated with DMPA and combined oral contraceptives (COCs) have not been studied. Cervical samples from 216 HIV seroconverters in Uganda and Zimbabwe with matched samples from 727 HIV-uninfected controls were collected at two quarterly visits before (t - 2, t - 1), at (t0), and two visits following (t + 1, t + 2) HIV seroconversion and corresponding visits for HIV-negative controls. We measured 10 biomarkers of inflammation and immunity and used generalized linear models to estimate and compare biomarker levels across HIV status, contraceptive, and pregnancy groups. Biomarkers remained relatively stable across visits for controls, while in HIV-infected women cervical immunity started to change before seroconversion with RANTES and BD-2 increased and secretory leukocyte protease inhibitor (SLPI) decreased at t - 1 and continued to change at t0 with ICAM-1 up and IL-8 down and with more biomarkers after seroconversion (IL-1ß, IL-6, MIP-3α, VEGF, and IL-1RA down and IL-1RA:IL-1ß ratio up). In multivariable analyses, seroconverters had higher BD-2 at t - 1, higher RANTES and lower SLPI from t - 1 through t + 2, and lower IL-8 and IL-1RA at and/or after seroconversion compared to nonseroconverters. Compared to non-HC users, DMPA users had higher RANTES at all visits and lower BD-2 at t - 2 through t0, while COC users and pregnant women had higher IL-8 and SLPI at all visits; COC users also had lower BD-2 preseroconversion; pregnant women had lower RANTES at t0 - t + 2. Longitudinal patterns of cervical immunity differ between HIV seroconverters and HIV-negative women; seroconverters demonstrate increased RANTES and decreased SLPI starting before and continuing postseroconversion. Furthermore, these patterns are differentially regulated by DMPA, COC, and pregnancy.


Asunto(s)
Cuello del Útero/inmunología , Anticonceptivos Hormonales Orales/inmunología , Infecciones por VIH/inmunología , Mediadores de Inflamación/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Cuello del Útero/metabolismo , Anticonceptivos Orales Combinados/inmunología , Anticonceptivos Hormonales Orales/administración & dosificación , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/metabolismo , Humanos , Estudios Longitudinales , Acetato de Medroxiprogesterona/inmunología , Embarazo , Seroconversión , Uganda/epidemiología , Frotis Vaginal , Adulto Joven , Zimbabwe/epidemiología
17.
Obstet Gynecol ; 110(5): 1003-9, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17978111

RESUMEN

OBJECTIVE: To estimate the probability of pregnancy for oral contraceptive pill (OCP), injectable contraceptive, and condom users in Uganda, Thailand, and Zimbabwe. METHODS: This study is a secondary analysis of 5,224 women who participated in a prospective study evaluating the association between hormonal contraception and human immunodeficiency virus (HIV) acquisition. RESULTS: The overall 12-month cumulative probability of pregnancy of injectable contraceptive users was 0.6% (95% confidence interval [CI] 0.3-1.0), with similar risks in Uganda (0.3%, 95% CI 0-0.7), Thailand (0.6%, 95% CI 0-1.2), and Zimbabwe (1.0%, 95% CI 0.3-1.7). The 12-month cumulative probability of pregnancy for OCP users was 9.5% (95% CI 8.1-11.0%), with similar risks of pregnancy in Uganda and Zimbabwe (14.6%, 95% CI 11.7-17.4; and 10.2%, 95% CI 8.0-12.5, respectively) but substantially lower risk in Thailand (0.5%, 95% CI 0-1.2). The overall 12-month cumulative probability of pregnancy for women intending to use a given method at baseline was 2.0% (95% CI 1.4-2.6%) for injectable contraceptives, 15.7% (95% CI 14.1-17.3%) for OCPs, and 25.8% (95% CI 23.2-28.4) for condoms. Women in Thailand experienced lower pregnancy risk with condoms (18.4%, 95% CI 11.1-25.7) than in Uganda (29.5%, 95% CI 25.7-33.4), and Zimbabwe (23.3%, 95% CI 19.4-27.2). CONCLUSION: The overall risk of pregnancy for injectable contraceptive users was substantially lower than for oral contraceptive pill users. However, Thai participants had similarly low cumulative pregnancy probabilities for both methods. Women receiving contraceptive counseling should be informed that their experience with a given method may differ from the average or typical-use pregnancy rates often discussed during contraceptive counseling. Tailored counseling is necessary for women to make informed choices. LEVEL OF EVIDENCE: II.


Asunto(s)
Condones , Anticonceptivos Femeninos/administración & dosificación , Anticonceptivos Orales Combinados/uso terapéutico , Acetato de Medroxiprogesterona/administración & dosificación , Índice de Embarazo , Adolescente , Adulto , Consejo , Femenino , Humanos , Inyecciones Intramusculares , Estimación de Kaplan-Meier , Embarazo , Estudios Prospectivos , Tailandia , Resultado del Tratamiento , Uganda , Zimbabwe
18.
Contraception ; 75(3): 185-92, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17303487

RESUMEN

BACKGROUND: The IUD is a highly effective, safe, inexpensive and long-lasting contraceptive. However, IUDs may increase PID risk during the early postinsertion period when inserted in women with cervical infections. We developed a simple algorithm to identify women at low risk of current sexually transmitted infection (STI) who are appropriate IUD candidates in regions with moderate or high STI prevalence. METHODS: We used data sets from family planning populations in Kenya, Zimbabwe, Jamaica and the United States to develop optimum algorithms. We then validated these algorithms using data sets from family planning populations in Thailand and Uganda. RESULTS: A simple unweighted algorithm based on age, living with partner, education, bleeding between periods and a behavioral risk score (number of sex partners, condom use) was the most useful. Adding clinical signs did not improve algorithm performance. Women categorized at low risk by this algorithm were at substantially reduced risks of cervical infection. Women identified at high STI risk had at least twice the risk as the overall clinic populations. Women in the moderate-risk group had STI risks similar to the overall clinic populations. CONCLUSION: Women categorized as low risk by the algorithm can be referred for IUD insertion while women categorized at high risk should not receive an IUD without further testing or treatment. Women in the moderate-risk group should be triaged based on the STI prevalence of the overall clinic population. A simple checklist has been developed to help providers estimate a client's risk of current STI and to guide appropriate triage.


Asunto(s)
Algoritmos , Dispositivos Intrauterinos , Medición de Riesgo , Enfermedades de Transmisión Sexual/epidemiología , Encuestas y Cuestionarios/normas , Adulto , Contraindicaciones , Femenino , Salud Global , Humanos , Dispositivos Intrauterinos/estadística & datos numéricos , Jamaica , Kenia , Prevalencia , Factores de Riesgo , Sensibilidad y Especificidad , Enfermedades de Transmisión Sexual/prevención & control , Enfermedades de Transmisión Sexual/transmisión , Estados Unidos , Salud de la Mujer , Zimbabwe
19.
Contraception ; 75(2): 136-41, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17241844

RESUMEN

OBJECTIVE: This study evaluated the effect of the so-called universal placebo compared to the polystyrene sulfonate (PSS) placebo on genital irritation. DESIGN: A single-center, Phase I, randomized, closed-label study was performed to evaluate the genital irritation of microbicide placebo gels. Thirty healthy, sexually abstinent women were randomly assigned to apply 3.5 mL of either the universal placebo or the PSS placebo gel intravaginally twice daily for 14 days. METHODS: Genital irritation was assessed by signs as seen on pelvic examination and colposcopy and reports of symptoms. Vaginal health was assessed by wet mounts, Gram stains for Nugent score and polymorphonuclear leukocytes, and semiquantitative vaginal cultures. Acceptability was assessed as reported on the follow-up questionnaire. RESULTS: The universal placebo was less irritating than the PSS placebo with a lower proportion of women experiencing signs and/or symptoms of genital irritation throughout follow-up (36% compared to 80%, p=.0253). The universal placebo was associated with few and mild genital symptoms, few and minor colposcopic findings and good vaginal health with no clinically significant changes in genital flora. Most participants found the feel of the universal placebo gel neutral or pleasant, and all participants found it odorless. CONCLUSIONS: The universal placebo appeared safe and acceptable when used twice daily for 14 days. The strategy of creating a de novo inert universal placebo is a successful approach. The universal placebo is appropriate for use as a placebo gel in HIV prevention trials with microbicide candidates.


Asunto(s)
Antiinfecciosos/efectos adversos , Infecciones por VIH/prevención & control , Poliestirenos/efectos adversos , Enfermedades Vaginales/inducido químicamente , Adolescente , Adulto , Antiinfecciosos/administración & dosificación , Método Doble Ciego , Femenino , Geles/administración & dosificación , Geles/efectos adversos , Humanos , Persona de Mediana Edad , Satisfacción del Paciente , Poliestirenos/administración & dosificación , Resultado del Tratamiento
20.
Can J Public Health ; 108(2): e135-e144, 2017 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-28621649

RESUMEN

OBJECTIVES: Home ownership as opposed to renting is associated with lower rates of food insecurity, the latter being a marker of household economic deprivation associated with adverse health outcomes. It is unclear whether this relationship persists during a major economic decline, or whether different subgroups of home owners are equally protected. The 2008-2009 recession in Canada was tied to events in the United States related to inappropriate mortgage financing; the impact of the recession on food insecurity among home owners may identify policies to mitigate recessionary outcomes. METHODS: We used a before-and-after natural experimental design using data from the Canadian Community Health Survey (CCHS) cycles 2007/2008 (pre-recession) and 2009/2010 (post-recession) with information on household food insecurity, home ownership versus renting, and socio-demographics. Applying multivariable logistic regression, we examined changes in household food insecurity by housing tenure and sex over the period. RESULTS: Pre-recession, food insecurity affected 3.3% of home owners and 17.1% of renter households. Among home owners, the risk of food insecurity increased post-recession by 10%, which was not statistically significant. Post-recession, and with adjustment, although renters' higher absolute risk of food insecurity persisted, male-respondent home owners experienced the highest rate of increase in food insecurity prevalence by subgroup (OR = 1.26, 95% CI: 1.06-1.50) versus renters (OR = 1.17, 95% CI: 1.05-1.29). CONCLUSION: Housing policies in Canada protected most home owners from precarity during the 2008-2009 economic recession; however, male-respondent home owners exhibited a unique economic vulnerability during this time. Implications of Canadian home ownership policies are discussed in light of differential vulnerability of home owner groups.


Asunto(s)
Recesión Económica , Composición Familiar , Abastecimiento de Alimentos/estadística & datos numéricos , Vivienda/estadística & datos numéricos , Propiedad/estadística & datos numéricos , Adolescente , Adulto , Anciano , Canadá , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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