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1.
Nat Med ; 29(12): 3224-3232, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38049621

RESUMEN

Cervical cancer burden is high where prophylactic vaccination and screening coverage are low. We demonstrated in a multicenter randomized, double-blind, controlled trial that single-dose human papillomavirus (HPV) vaccination had high vaccine efficacy (VE) against persistent infection at 18 months in Kenyan women. Here, we report findings of this trial through 3 years of follow-up. Overall, 2,275 healthy women aged 15-20 years were recruited and randomly assigned to receive bivalent (n = 760), nonavalent (n = 758) or control (n = 757) vaccine. The primary outcome was incident-persistent vaccine type-specific cervical HPV infection. The primary evaluation was superiority analysis in the modified intention-to-treat (mITT) HPV 16/18 and HPV 16/18/31/33/45/52/58 cohorts. The trial met its prespecified end points of vaccine type-specific persistent HPV infection. A total of 75 incident-persistent infections were detected in the HPV 16/18 mITT cohort: 2 in the bivalent group, 1 in the nonavalent group and 72 in the control group. Nonavalent VE was 98.8% (95% CI 91.3-99.8%, P < 0.0001) and bivalent VE was 97.5% (95% CI 90.0-99.4%, P < 0.0001). Overall, 89 persistent infections were detected in the HPV 16/18/31/33/45/52/58 mITT cohort: 5 in the nonavalent group and 84 in the control group; nonavalent VE was 95.5% (95% CI 89.0-98.2%, P < 0.0001). There were no vaccine-related severe adverse events. Three years after vaccination, single-dose HPV vaccination was highly efficacious, safe and conferred durable protection. ClinicalTrials.gov no. NCT03675256 .


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Kenia/epidemiología , Papillomaviridae , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/efectos adversos , Infección Persistente , Neoplasias del Cuello Uterino/prevención & control , Vacunación/métodos , Método Doble Ciego
2.
NPJ Vaccines ; 8(1): 98, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37433788

RESUMEN

As part of a multicenter study evaluating homologous and heterologous COVID-19 booster vaccines, we assessed the magnitude, breadth, and short-term durability of binding and pseudovirus-neutralizing antibody (PsVNA) responses following a single booster dose of NVX-CoV2373 in adults primed with either Ad26.COV2.S, mRNA-1273, or BNT162b2 vaccines. NVX-CoV2373 as a heterologous booster was immunogenic and associated with no safety concerns through Day 91. Fold-rises in PsVNA titers from baseline (Day 1) to Day 29 were highest for prototypic D614G variant and lowest for more recent Omicron sub-lineages BQ.1.1 and XBB.1. Peak humoral responses against all SARS-CoV-2 variants were lower in those primed with Ad26.COV2.S than with mRNA vaccines. Prior SARS CoV-2 infection was associated with substantially higher baseline PsVNA titers, which remained elevated relative to previously uninfected participants through Day 91. These data support the use of heterologous protein-based booster vaccines as an acceptable alternative to mRNA or adenoviral-based COVID-19 booster vaccines. This trial was conducted under ClinicalTrials.gov: NCT04889209.

3.
Cell Rep Med ; 3(7): 100679, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35798000

RESUMEN

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibits reduced susceptibility to vaccine-induced neutralizing antibodies, requiring a boost to generate protective immunity. We assess the magnitude and short-term durability of neutralizing antibodies after homologous and heterologous boosting with mRNA and Ad26.COV2.S vaccines. All prime-boost combinations substantially increase the neutralization titers to Omicron, although the boosted titers decline rapidly within 2 months from the peak response compared with boosted titers against the prototypic D614G variant. Boosted Omicron neutralization titers are substantially higher for homologous mRNA vaccine boosting, and for heterologous mRNA and Ad26.COV2.S vaccine boosting, compared with homologous Ad26.COV2.S boosting. Homologous mRNA vaccine boosting generates nearly equivalent neutralizing activity against Omicron sublineages BA.1, BA.2, and BA.3 but modestly reduced neutralizing activity against BA.2.12.1 and BA.4/BA.5 compared with BA.1. These results have implications for boosting requirements to protect against Omicron and future variants of SARS-CoV-2. This trial was conducted under ClincalTrials.gov: NCT04889209.


Asunto(s)
COVID-19 , Vacunas Virales , Ad26COVS1 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Humanos , ARN Mensajero , SARS-CoV-2/genética , Vacunas Sintéticas , Vacunas de ARNm
4.
NEJM Evid ; 1(5): EVIDoa2100056, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35693874

RESUMEN

Background: Single-dose HPV vaccination, if efficacious, would be tremendously advantageous; simplifying implementation and decreasing costs. Methods: We performed a randomized, multi-center, double-blind, controlled trial of single-dose nonavalent (HPV 16/18/31/33/45/52/58/6/11) or bivalent (HPV 16/18) HPV vaccination compared to meningococcal vaccination among Kenyan women aged 15-20 years. Enrollment and six monthly cervical swabs and a month three vaginal swab were tested for HPV DNA. Enrollment sera were tested for HPV antibodies. The modified intent-to-treat (mITT) cohort comprised participants who tested HPV antibody negative at enrollment and HPV DNA negative at enrollment and month three. The primary outcome was incident persistent vaccine-type HPV infection by month 18. Results: Between December 2018 and June 2021, 2,275 women were randomly assigned and followed; 758 received the nonavalent HPV vaccine, 760 the bivalent HPV vaccine, and 757 the meningococcal vaccine; retention was 98%. Thirty-eight incident persistent infections were detected in the HPV 16/18 mITT cohort: one each among participants assigned to the bivalent and nonavalent groups and 36 among those assigned to the meningococcal group; nonavalent Vaccine Efficacy (VE) was 97.5% (95%CI 81.7-99.7%, p=<0.0001), and bivalent VE was 97.5% (95%CI 81.6-99.7%, p=<0.0001). Thirty-three incident persistent infections were detected in the HPV 16/18/31/33/45/52/58 mITT cohort: four in the nonavalent group and 29 in the meningococcal group; nonavalent VE for HPV 16/18/31/33/45/52/58 was 88.9% (95%CI 68.5-96.1%, p<0.0001). The rate of SAEs was 4.5-5.2% by group. Conclusions: Over the 18 month time-frame we studied, single-dose bivalent and nonavalent HPV vaccines were each highly effective in preventing incident persistent oncogenic HPV infection, similar to multidose regimens.

5.
AIDS ; 36(2): 257-265, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34172672

RESUMEN

OBJECTIVE: Vaccine-preventable human papillomavirus (HPV) infection is common, especially in sub-Saharan Africa where HIV risk is also high. However, unlike other sexually transmitted infections (STIs), HPV's role in HIV acquisition is unclear. We evaluated this relationship using data from MTN-003, a clinical trial of HIV chemoprophylaxis among cisgender women in sub-Saharan Africa. DESIGN: A case-control study. METHODS: We matched 138 women who acquired HIV (cases) to 412 HIV-negative controls. Cervicovaginal swabs collected within 6 months before HIV seroconversion were tested for HPV DNA. We estimated the associations between carcinogenic (high-risk) and low-risk HPV types and types targeted by HPV vaccines and HIV acquisition, using conditional logistic regression models adjusted for time-varying sexual behaviors and other STIs. RESULTS: Mean age was 23 (±4) years. Any, high-risk and low-risk HPV was detected in 84, 74 and 66% of cases, and 65, 55 and 48% of controls. Infection with at least two HPV types was common in cases (67%) and controls (49%), as was infection with nonavalent vaccine-targeted types (60 and 42%). HIV acquisition increased with any [adjusted odds ratio (aOR) 2.5, 95% confidence interval (95% CI) 1.3-4.7], high-risk (aOR 2.6, 95% CI 1.5-4.6) and low-risk (aOR 1.8, 95% CI 1.1-2.9) HPV. Each additional type detected increased HIV risk by 20% (aOR 1.2, 95% CI 1.1-1.4). HIV acquisition was associated with HPV types targeted by the nonavalent (aOR 2.1, 95% CI 1.3-3.6) and quadrivalent vaccines (aOR 1.9, 95% CI 1.1-3.2). CONCLUSION: HPV infection is associated with HIV acquisition in sub-Saharan African women. In addition to preventing HPV-associated cancers, increasing HPV vaccination coverage could potentially reduce HIV incidence.


Asunto(s)
Alphapapillomavirus , Infecciones por VIH , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Adulto , Estudios de Casos y Controles , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/prevención & control , Prevalencia , Factores de Riesgo , Vacunación , Adulto Joven
6.
medRxiv ; 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34671773

RESUMEN

Background: While Coronavirus disease 2019 (Covid-19) vaccines are highly effective, breakthrough infections are occurring. Booster vaccinations have recently received emergency use authorization (EUA) for certain populations but are restricted to homologous mRNA vaccines. We evaluated homologous and heterologous booster vaccination in persons who had received an EUA Covid-19 vaccine regimen. Methods: In this phase 1/2 open-label clinical trial conducted at ten U.S. sites, adults who received one of three EUA Covid-19 vaccines at least 12 weeks prior to enrollment and had no reported history of SARS-CoV-2 infection received a booster injection with one of three vaccines (Moderna mRNA-1273 100-µg, Janssen Ad26.COV2.S 5×1010 virus particles, or Pfizer-BioNTech BNT162b2 30-µg; nine combinations). The primary outcomes were safety, reactogenicity, and humoral immunogenicity on study days 15 and 29. Results: 458 individuals were enrolled: 154 received mRNA-1273, 150 received Ad26.CoV2.S, and 153 received BNT162b2 booster vaccines. Reactogenicity was similar to that reported for the primary series. Injection site pain, malaise, headache, and myalgia occurred in more than half the participants. Booster vaccines increased the neutralizing activity against a D614G pseudovirus (4.2-76-fold) and binding antibody titers (4.6-56-fold) for all combinations; homologous boost increased neutralizing antibody titers 4.2-20-fold whereas heterologous boost increased titers 6.2-76-fold. Day 15 neutralizing and binding antibody titers varied by 28.7-fold and 20.9-fold, respectively, across the nine prime-boost combinations. Conclusion: Homologous and heterologous booster vaccinations were well-tolerated and immunogenic in adults who completed a primary Covid-19 vaccine regimen at least 12 weeks earlier.

7.
Trials ; 22(1): 661, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34579786

RESUMEN

BACKGROUND: HPV infection is the primary cause of cervical cancer, a leading cause of cancer among women in Kenya and many sub-Saharan African countries. High coverage of HPV vaccination is a World Health Organization priority to eliminate cervical cancer globally, but vaccine supply and logistics limit widespread implementation of the current two or three dose HPV vaccine schedule. METHODS: We are conducting an individual randomized controlled trial to evaluate whether a single dose of the bivalent (HPV 16/18) or nonavalent (HPV 16/18/31/33/45/52/58/6/11) HPV vaccine prevents persistent HPV infection, a surrogate marker for precancerous lesions and cervical cancer. The primary objective is to compare the efficacy of immediate, single-dose bivalent or nonavalent vaccination with delayed HPV vaccination. Kenyan women age 15-20 years old are randomized to immediate bivalent HPV and delayed meningococcal vaccine (group 1), immediate nonavalent HPV vaccine and delayed meningococcal vaccine (group 2), or immediate meningococcal vaccine and delayed HPV vaccine (group 3) with 36 months of follow-up. The primary outcome is persistent vaccine-type HPV infection by month 18 and by month 36 for the final durability outcome. The secondary objectives include to (1) evaluate non-inferiority of antibody titers among girls and adolescents (age 9 to 14 years) from another Tanzanian study, the DoRIS Study (NCT02834637), compared to KEN SHE Study participants; (2) assess the memory B cell immune response at months 36 and 37; and (3) estimate cost-effectiveness using the trial results and health economic models. DISCUSSION: This study will evaluate single-dose HPV vaccine efficacy in Africa and has the potential to guide public health policy and increase HPV vaccine coverage. The secondary aims will assess generalizability of the trial results by evaluating immunobridging from younger ages, durability of the immune response, and the long-term health benefits and cost of single-dose HPV vaccine delivery. TRIAL REGISTRATION: ClinicalTrials.gov NCT03675256 . Registered on September 18, 2018.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Adolescente , Niño , Femenino , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Humanos , Kenia , Infecciones por Papillomavirus/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Neoplasias del Cuello Uterino/prevención & control , Vacunación , Adulto Joven
8.
Circ Cardiovasc Imaging ; 14(1): e011981, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33461306

RESUMEN

BACKGROUND: A limitation of the Agatston coronary artery calcium (CAC) score is that it does not use all of the calcium density information in the computed tomography scan such that many individuals have a score of zero. We examined the predictive validity for incident coronary heart disease (CHD) events of the spatially weighted coronary calcium score (SWCS), an alternative scoring method for CAC that assigns scores to individuals with Agatston CAC=0. METHODS: The MESA (Multi-Ethnic Study of Atherosclerosis) is a longitudinal study that conducted a baseline exam from 2000 to 2002 in 6814 participants including computed tomography scanning for CAC. Subsequent exams and systematic follow-up of the cohort for outcomes were performed. Statistical models were adjusted using the MESA risk score based on age, sex, race/ethnicity, systolic blood pressure, use of hypertension medications, diabetes, total and HDL (high-density lipoprotein) cholesterol, use of lipid-lowering medications, smoking status, and family history of heart attack. RESULTS: In the 3286 participants with Agatston CAC=0 at baseline and for whom SWCS was computed, 98 incident CHD events defined as definite or probably myocardial infarction or definite CHD death occurred during a median follow-up of 15.1 years. In this group, SWCS predicted incident CHD events after multivariable adjustment (hazard ratio=1.30 per SD of natural logarithm [SWCS] [95% CI, 1.04-1.60]; P=0.005); and progression from Agatston CAC=0 at baseline to CAC>0 at subsequent exams (multivariable-adjusted incidence rate difference per SD of natural logarithm [SWCS] per 100 person-years 1.68 [95% CI, 1.03-2.33]; P<0.0001). CONCLUSIONS: SWCS predicts incident CHD events in individuals with Agatston CAC score=0 as well as conversion to Agatston CAC>0 at repeat computed tomography scanning at later exams. SWCS has predictive validity as a subclinical phenotype and marker of CHD risk in individuals with Agatston CAC=0.


Asunto(s)
Aterosclerosis/diagnóstico , Calcio/metabolismo , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/metabolismo , Etnicidad , Medición de Riesgo/métodos , Anciano , Aterosclerosis/etnología , Aterosclerosis/metabolismo , Enfermedad de la Arteria Coronaria/etnología , Enfermedad de la Arteria Coronaria/metabolismo , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos X , Estados Unidos/epidemiología
9.
AIDS ; 34(4): 559-567, 2020 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-31764068

RESUMEN

OBJECTIVE: We aimed to determine if the dapivirine vaginal ring and the ring device alone (flexible silicone matrix polymer) was associated with the development of cervical cytology abnormalities. DESIGN: Secondary analysis comparing cervical cytology results between two randomized controlled microbicide trials (MTN-020/ASPIRE and MTN-003/VOICE). METHODS: Data from ASPIRE, a phase III, placebo-controlled trial of the dapivirine vaginal ring, were used in this analysis. Cervical cytology smears were evaluated at baseline and at the final visit with product use. We compared cytology results between women randomized to dapivirine versus placebo vaginal ring. We further assessed for the effect of the vaginal ring device on cervical cytology by comparing results with data from the oral placebo arm of VOICE, a prior HIV-1 prevention trial conducted in a similar population. RESULTS: Cervical cytology results for 2394 women from ASPIRE (1197 per study arm) were used in this analysis; median time between baseline and final visit with product use was 22.1 months. Cytology smear findings were comparable between dapivirine and placebo vaginal ring arms: at final visit, normal: 90.6 versus 91.5%, ASC-US//LSIL: 7.8 versus 7.4%, ASC-H/HSIL/AGC/AGC-favor neoplastic: 1.7 versus 1.1%, P = 0.44. Cytology data from VOICE had findings (normal: 87.8%, ASC-US/LSIL: 9.8%, ASC-H/HSIL/AGC/AGC-favor neoplastic: 2.4%) comparable with that of both dapivirine (P = 0.93) and placebo vaginal ring arms (P = 0.24). CONCLUSION: These findings indicate that neither use of the dapivirine vaginal ring nor the vaginal ring device alone, over a period of 2 years, is associated with development of cervical cytology abnormalities that could lead to precancerous or cancerous lesions.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH/prevención & control , Pirimidinas/administración & dosificación , Adulto , Método Doble Ciego , Femenino , Infecciones por VIH/virología , Seropositividad para VIH , VIH-1 , Humanos , Vagina/virología , Adulto Joven
10.
Radiographics ; 39(5): 1368-1392, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31498743

RESUMEN

Gender-affirming surgeries expand the options for physical transition among transgender patients, those whose gender identity is incongruent with the sex assigned to them at birth. Growing medical insight, increasing public acceptance, and expanding insurance coverage have improved the access to and increased the demand for gender-affirming surgeries in the United States. Procedures for transgender women, those patients with feminine gender identity, include breast augmentation using implants and genital reconstruction with vaginoplasty. Some transgender women receive medically unapproved silicone injections for breast augmentation or other soft-tissue contouring procedures that can lead to disfigurement, silicone pulmonary embolism, systemic reactions, and even death. MRI is preferred over CT for postvaginoplasty evaluation given its superior tissue contrast resolution. Procedures for transgender men, patients with a masculine gender identity, include chest masculinization (mastectomy) and genital reconstruction (phalloplasty or metoidioplasty, scrotoplasty, and erectile device implantation). Urethrography is the standard imaging modality performed to evaluate neourethral patency and other complications, such as leaks and fistulas. Despite a sizeable growth in the surgical literature about gender-affirming surgeries and their outcomes, detailed descriptions of the imaging features following these surgeries remain sparse. Radiologists must be aware of the wide variety of anatomic and pathologic changes unique to patients who undergo gender-affirming surgeries to ensure accurate imaging interpretation. Online supplemental material is available for this article. ©RSNA, 2019.


Asunto(s)
Diagnóstico por Imagen , Procedimientos de Reasignación de Sexo , Personas Transgénero , Femenino , Humanos , Masculino
11.
PLoS One ; 8(11): e80927, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24282559

RESUMEN

BACKGROUND: Four clinical trials have shown that oral and topical pre-exposure prophylaxis (PrEP) based on tenofovir may be effective in preventing HIV transmission. The expected reduction in HIV transmission and the projected prevalence of drug resistance due to PrEP use vary significantly across modeling studies as a result of the broad spectrum of assumptions employed. Our goal is to quantify the influence of drug resistance assumptions on the predicted population-level impact of PrEP. METHODS: All modeling studies which evaluate the impact of oral or topical PrEP are reviewed and key assumptions regarding mechanisms of generation and spread of drug-resistant HIV are identified. A dynamic model of the HIV epidemic is developed to assess and compare the impact of oral PrEP using resistance assumptions extracted from published studies. The benefits and risks associated with ten years of PrEP use are evaluated under identical epidemic, behavioral and intervention conditions in terms of cumulative fractions of new HIV infections prevented, resistance prevalence among those infected with HIV, and fractions of infections in which resistance is transmitted. RESULTS: Published models demonstrate enormous variability in resistance-generating assumptions and uncertainty in parameter values. Depending on which resistance parameterization is used, a resistance prevalence between 2% and 44% may be expected if 50% efficacious oral PrEP is used consistently by 50% of the population over ten years. We estimated that resistance may be responsible for up to a 10% reduction or up to a 30% contribution to the fraction of prevented infections predicted in different studies. CONCLUSIONS: Resistance assumptions used in published studies have a strong influence on the projected impact of PrEP. Modelers and virologists should collaborate toward clarifying the set of resistance assumptions biologically relevant to the PrEP products which are already in use or soon to be added to the arsenal against HIV.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Farmacorresistencia Viral , Infecciones por VIH/prevención & control , Femenino , VIH/efectos de los fármacos , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Humanos , Masculino , Modelos Teóricos
12.
Pediatr Infect Dis J ; 32(4): e164-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23249916

RESUMEN

BACKGROUND: The HIV Prevention Trials Network (HPTN) 046 trial evaluated the efficacy of extended infant nevirapine (NVP) administration for prevention of HIV transmission through breastfeeding. Infants received daily NVP up to 6 weeks of age. HIV-uninfected infants (the intent-to-treat group) received daily NVP or placebo up to 6 months of age. We analyzed emergence of NVP resistance in infants who acquired HIV infection despite prophylaxis. METHODS: HIV genotyping was performed using the ViroSeq HIV Genotyping System. Medians and proportions were used to summarize data. Two-sided Fisher exact tests were used to evaluate associations between categorical variables. RESULTS: NVP resistance was detected in 12 (92.3%) of 13 infants who were HIV-infected by 6 weeks and in 7 (28%) of 25 infants who were HIV-uninfected at 6 weeks and HIV-infected at 6 months of age (6/8 = 75% in the NVP arm, 1/17 = 5.9% in the placebo arm, P = 0.001). Among those 25 infants, 4 had mothers who initiated an antiretroviral treatment regimen by 6 months postpartum. In all 4 cases, the treatment regimen included a non-nucleoside reverse transcriptase inhibitor (NVP or efavirenz). NVP resistance was detected in all 4 of those infants by 6 months of age (4/4 = 100%). In contrast, only 3 (14.2%) of the remaining 21 HIV-infected infants whose mothers did not initiate antiretroviral treatment developed NVP resistance (P = 0.003). CONCLUSIONS: Extended NVP prophylaxis significantly increased the risk of NVP resistance in infants who acquired HIV infection after 6 weeks of age. Treatment of maternal HIV infection was also associated with emergence of NVP resistance in HIV-infected, breastfed infants.


Asunto(s)
Antirretrovirales/administración & dosificación , Lactancia Materna , Quimioprevención/métodos , Farmacorresistencia Viral , Infecciones por VIH/prevención & control , VIH-1/aislamiento & purificación , Nevirapina/administración & dosificación , Antirretrovirales/farmacología , Femenino , Genotipo , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Lactante , Recién Nacido , Masculino , Nevirapina/farmacología , Placebos , ARN Viral/genética , Tanzanía , Resultado del Tratamiento , Uganda , Zimbabwe
13.
PLoS One ; 7(11): e48328, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23144863

RESUMEN

Because lubricants may decrease trauma during coitus, it is hypothesized that they could aid in the prevention of HIV acquisition. Therefore, safety and anti-HIV-1 activity of over-the-counter (OTC) aqueous- (n = 10), lipid- (n = 2), and silicone-based (n = 2) products were tested. The rheological properties of the lipid-based lubricants precluded testing with the exception of explant safety testing. Six aqueous-based gels were hyperosmolar, two were nearly iso-osmolar, and two were hypo-osmolar. Evaluation of the panel of products showed Gynol II (a spermicidal gel containing 2% nonoxynol-9), KY Jelly, and Replens were toxic to Lactobacillus. Two nearly iso-osmolar aqueous- and both silicone-based gels were not toxic toward epithelial cell lines or ectocervical or colorectal explant tissues. Hyperosmolar lubricants demonstrated reduction of tissue viability and epithelial fracture/sloughing while the nearly iso-osmolar and silicon-based lubricants showed no significant changes in tissue viability or epithelial modifications. While most of the lubricants had no measurable anti-HIV-1 activity, three lubricants which retained cell viability did demonstrate modest anti-HIV-1 activity in vitro. To determine if this would result in protection of mucosal tissue or conversely determine if the epithelial damage associated with the hyperosmolar lubricants increased HIV-1 infection ex vivo, ectocervical tissue was exposed to selected lubricants and then challenged with HIV-1. None of the lubricants that had a moderate to high therapeutic index protected the mucosal tissue. These results show hyperosmolar lubricant gels were associated with cellular toxicity and epithelial damage while showing no anti-viral activity. The two iso-osmolar lubricants, Good Clean Love and PRÉ, and both silicone-based lubricants, Female Condom 2 lubricant and Wet Platinum, were the safest in our testing algorithm.


Asunto(s)
Fármacos Anti-VIH/farmacología , Infecciones por VIH/prevención & control , VIH-1/efectos de los fármacos , Lubricantes/farmacología , Fármacos Anti-VIH/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Celulosa/análogos & derivados , Celulosa/química , Celulosa/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/fisiología , Femenino , Glicerol/química , Glicerol/farmacología , Humanos , Lactobacillus/efectos de los fármacos , Lubricantes/química , Viabilidad Microbiana/efectos de los fármacos , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/patología , Membrana Mucosa/virología , Medicamentos sin Prescripción , Concentración Osmolar , Fosfatos/química , Fosfatos/farmacología , Glicoles de Propileno/química , Glicoles de Propileno/farmacología , Geles de Silicona , Espermicidas/química , Espermicidas/farmacología , Viscosidad
14.
BMC Med Imaging ; 12: 14, 2012 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-22747658

RESUMEN

BACKGROUND: Extent of atherosclerosis measured by amount of coronary artery calcium (CAC) in computed tomography (CT) has been traditionally assessed using thresholded scoring methods, such as the Agatston score (AS). These thresholded scores have value in clinical prediction, but important information might exist below the threshold, which would have important advantages for understanding genetic, environmental, and other risk factors in atherosclerosis. We developed a semi-automated threshold-free scoring method, the spatially weighted calcium score (SWCS) for CAC in the Multi-Ethnic Study of Atherosclerosis (MESA). METHODS: Chest CT scans were obtained from 6814 participants in the Multi-Ethnic Study of Atherosclerosis (MESA). The SWCS and the AS were calculated for each of the scans. Cox proportional hazards models and linear regression models were used to evaluate the associations of the scores with CHD events and CHD risk factors. CHD risk factors were summarized using a linear predictor. RESULTS: Among all participants and participants with AS > 0, the SWCS and AS both showed similar strongly significant associations with CHD events (hazard ratios, 1.23 and 1.19 per doubling of SWCS and AS; 95% CI, 1.16 to 1.30 and 1.14 to 1.26) and CHD risk factors (slopes, 0.178 and 0.164; 95% CI, 0.162 to 0.195 and 0.149 to 0.179). Even among participants with AS = 0, an increase in the SWCS was still significantly associated with established CHD risk factors (slope, 0.181; 95% CI, 0.138 to 0.224). The SWCS appeared to be predictive of CHD events even in participants with AS = 0, though those events were rare as expected. CONCLUSIONS: The SWCS provides a valid, continuous measure of CAC suitable for quantifying the extent of atherosclerosis without a threshold, which will be useful for examining novel genetic and environmental risk factors for atherosclerosis.


Asunto(s)
Calcinosis/diagnóstico por imagen , Calcinosis/etnología , Angiografía Coronaria/estadística & datos numéricos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/etnología , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Estados Unidos/etnología
15.
Atherosclerosis ; 209(1): 226-9, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19766217

RESUMEN

OBJECTIVE: Inflammatory markers predict coronary heart disease (CHD). However, associations with coronary artery calcium (CAC), a marker of subclinical CHD, are not established. METHODS: We examined cross-sectional associations of C-reactive protein (CRP), interleukin-6 (IL-6) and fibrinogen with CAC presence (Agatston score>0 by computed tomography) in 6783 Multi-Ethnic Study of Atherosclerosis (MESA) participants. RESULTS: In all participants, those in the highest, compared to lowest, quartile of CRP had a relative risk (RR, 95% confidence interval) of 1.13 (1.06-1.19; p<0.01) for CAC in age, sex and ethnicity adjusted models. For highest versus lowest quartiles, relative risks were 1.22 (1.15-1.30; p<0.01) for IL-6 and 1.18 (1.11-1.24; p<0.01) for fibrinogen. Adjusting for CHD risk factors (smoking, diabetes, blood pressure, obesity and dyslipidemia) attenuated RRs. RRs for CAC were 1.05 (0.99-1.12; p=0.63) for CRP, 1.12 (1.06-1.20; p<0.01) for IL-6 and 1.09 (1.02-1.16; p=0.01) for fibrinogen in multivariable adjusted models. Results were similar for men and women and across ethnic groups. CONCLUSION: Inflammatory markers were weakly associated with CAC presence and burden in MESA. Our data support the hypothesis that inflammatory biomarkers and CAC reflect distinct pathophysiology.


Asunto(s)
Aterosclerosis/epidemiología , Proteína C-Reactiva/análisis , Calcinosis/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Vasos Coronarios , Fibrinógeno/análisis , Inflamación/sangre , Interleucina-6/sangre , Anciano , Pueblo Asiatico , Aterosclerosis/sangre , Aterosclerosis/etnología , Biomarcadores/sangre , Población Negra , Calcinosis/sangre , Calcinosis/etnología , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/etnología , Femenino , Hispánicos o Latinos , Humanos , Masculino , Persona de Mediana Edad , Población Blanca
16.
Am J Clin Nutr ; 88(3): 645-50, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18779279

RESUMEN

BACKGROUND: Excessive non-subcutaneous fat deposition may impair the functions of surrounding tissues and organs through the release of inflammatory cytokines and free fatty acids. OBJECTIVE: We examined the cross-sectional association between non-subcutaneous adiposity and calcified coronary plaque, a noninvasive measure of coronary artery disease burden. DESIGN: Participants in the Multi-Ethnic Study of Atherosclerosis underwent computed tomography (CT) assessment of calcified coronary plaque. We measured multiple fat depots in 398 white and black participants (47% men, 43% black), aged 47-86 y, from Forsyth County, NC, during 2002-2005, with the use of cardiac and abdominal CT scans. In addition to examining each depot separately, we also created a non-subcutaneous fat index with the standard scores of non-subcutaneous fat depots. RESULTS: A total of 219 participants (55%) were found to have calcified coronary plaque. After adjusting for demographics, lifestyle factors, and height, calcified coronary plaque was associated with a 1 SD increment in the non-subcutaneous fat index [odds ratio (OR): 1.41; 95% CI: 1.08, 1.84], pericardial fat (OR: 1.38; 95% CI: 1.04, 1.84), abdominal visceral fat (OR: 1.35; 95% CI: 1.03, 1.76) but not with fat content in the liver, intermuscular fat, or abdominal subcutaneous fat. The relation between non-subcutaneous fat index and calcified coronary plaque remained after further adjustment for abdominal subcutaneous fat (OR: 1.40; 95% CI: 1.00, 1.94). The relation did not differ by sex and ethnicity. CONCLUSIONS: The overall burden of non-subcutaneous fat deposition, but not abdominal subcutaneous fat, may be a correlate of coronary atherosclerosis.


Asunto(s)
Tejido Adiposo/anatomía & histología , Tejido Adiposo/patología , Aterosclerosis/fisiopatología , Calcinosis/fisiopatología , Estenosis Coronaria/fisiopatología , Etnicidad , Anciano , Anciano de 80 o más Años , Población Negra , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Piel , Población Blanca
17.
Radiology ; 247(3): 669-75, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18413889

RESUMEN

PURPOSE: To develop a new calcium score for use with unenhanced cardiac computed tomography (CT) that can be used to define the percentage of coronary arteries affected by calcium and to correlate this score with risk factors and cardiovascular events. MATERIALS AND METHODS: Institutional review boards at all participating centers approved this HIPAA-compliant study, and all participants gave written informed consent. Calcium coverage score (CCS), which represents the percentage of coronary arteries affected by calcific plaque, was calculated for 3252 participants in the Multi-Ethnic Study of Atherosclerosis in whom calcific plaque was detected with CT. Quasi-Poisson models were used to estimate associations (assessed by using t tests with robust standard errors) between CCS and risk factors. Associations between the CCS, Agatston, and calcium mass scores (hereafter, mass scores) and outcomes were estimated and assessed by using Cox proportional hazards models with Wald tests. The predictive ability of these models was assessed by using area under the receiver operating characteristic curves and bootstrap t tests. RESULTS: After adjustments were made for age, race, ethnicity, and sex in the quasi-Poisson model, CCS was associated with hypertension, dyslipidemia, and diabetes (P < .001 for all diseases). After adjustments for age and sex, a twofold increase in CCS was associated with a 52% (95% confidence interval: 34%, 72%) increase in risk for any coronary heart disease (CHD) event. When Agatston or mass scores were included with CCS in a Cox model for prediction of CHD events, neither Agatston score nor mass score was a significant predictor, whereas CCS remained significantly associated with CHD events. Although receiver operating characteristic curves suggested that there was a difference between CCS score and Agatston and mass scores in prediction of a cardiac event, no differences in prediction of hard cardiac events (myocardial infarction, death) were found. CONCLUSION: Both spatial distribution and amount of calcified plaque contribute to risk for CHD.


Asunto(s)
Calcinosis/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Anciano de 80 o más Años , Calcinosis/epidemiología , Calcinosis/etnología , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Distribución de Poisson , Valor Predictivo de las Pruebas , Prevalencia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Curva ROC , Radiografía Torácica , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiología
18.
Biometrics ; 59(3): 686-93, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14601770

RESUMEN

Complex issues arise when investigating the association between longitudinal immunologic measures and time to an event, such as time to relapse, in cancer vaccine trials. Unlike many clinical trials, we may encounter patients who are cured and no longer susceptible to the time-to-event endpoint. If there are cured patients in the population, there is a plateau in the survival function, S(t), after sufficient follow-up. If we want to determine the association between the longitudinal measure and the time-to-event in the presence of cure, existing methods for jointly modeling longitudinal and survival data would be inappropriate, since they do not account for the plateau in the survival function. The nature of the longitudinal data in cancer vaccine trials is also unique, as many patients may not exhibit an immune response to vaccination at varying time points throughout the trial. We present a new joint model for longitudinal and survival data that accounts both for the possibility that a subject is cured and for the unique nature of the longitudinal data. An example is presented from a cancer vaccine clinical trial.


Asunto(s)
Vacunas contra el Cáncer/farmacología , Ensayos Clínicos como Asunto/estadística & datos numéricos , Neoplasias/terapia , Teorema de Bayes , Biometría , Humanos , Estudios Longitudinales , Modelos Estadísticos , Neoplasias/inmunología , Neoplasias/mortalidad , Tasa de Supervivencia
19.
Biometrics ; 59(2): 221-8, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12926706

RESUMEN

This article proposes a new semiparametric Bayesian hierarchical model for the joint modeling of longitudinal and survival data. We relax the distributional assumptions for the longitudinal model using Dirichlet process priors on the parameters defining the longitudinal model. The resulting posterior distribution of the longitudinal parameters is free of parametric constraints, resulting in more robust estimates. This type of approach is becoming increasingly essential in many applications, such as HIV and cancer vaccine trials, where patients' responses are highly diverse and may not be easily modeled with known distributions. An example will be presented from a clinical trial of a cancer vaccine where the survival outcome is time to recurrence of a tumor. Immunologic measures believed to be predictive of tumor recurrence were taken repeatedly during follow-up. We will present an analysis of this data using our new semiparametric Bayesian hierarchical joint modeling methodology to determine the association of these longitudinal immunologic measures with time to tumor recurrence.


Asunto(s)
Teorema de Bayes , Modelos Estadísticos , Análisis de Supervivencia , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/normas , Ensayos Clínicos como Asunto/métodos , Gangliósido G(M2)/inmunología , Gangliósido G(M2)/uso terapéutico , Humanos , Inmunoterapia/métodos , Inmunoterapia/normas , Estudios Longitudinales , Melanoma/inmunología , Melanoma/terapia , Modelos Biológicos , Recurrencia Local de Neoplasia/inmunología , Recurrencia Local de Neoplasia/prevención & control
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