Combination treatment with zidovudine, didanosine, and nevirapine in infants with human immunodeficiency virus type 1 infection

BACKGROUND: In infants and children with maternally acquired human immunodeficiency virus type 1 (HIV-1) infection, treatment with a single antiretroviral agent has limited efficacy. We evaluated the safety and efficacy of a three-drug regimen in a small group of maternally infected infants. METHODS: Zidovudine, didanosine, and nevirapine were administered in combination orally to eight infants 2 to 16 months of age. The efficacy of antiretroviral treatment was evaluated by serial measurements of plasma HIV-1 RNA, quantitative plasma cultures, and quantitative cultures of peripheral-blood mononuclear cells. RESULTS: The three-drug regimen was well tolerated, without clinically important adverse events. Within four weeks, there were reductions in plasma levels of HIV-1 RNA of at least 96 percent (1.5 log) in seven of the eight study patients. Over the 6-month study period, replication of HIV-1 was controlled in two infants who began therapy at 2 1/2 months of age. Plasma RNA levels were reduced by 0.5 to 1.5 log in five of the other six infants. CONCLUSIONS: Although further observations are needed, it appears that in infants with maternally acquired HIV-1 infection, combined treatment with zidovudine, didanosine, and nevirapine is well tolerated and has sustained efficacy against HIV-1

Kepler Mission Stellar and Instrument Noise Properties

Kepler Mission results are rapidly contributing to fundamentally new discoveries in both the exoplanet and asteroseismology fields. The data returned from Kepler are unique in terms of the number of stars observed, precision of photometry for time series observations, and the temporal extent of high duty cycle observations. As the first mission to provide extensive time series measurements on thousands of stars over months to years at a level hitherto possible only for the Sun, the results from Kepler will vastly increase our knowledge of stellar variability for quiet solar-type stars. Here we report on the stellar noise inferred on the timescale of a few hours of most interest for detection of exoplanets via transits. By design the data from moderately bright Kepler stars are expected to have roughly comparable levels of noise intrinsic to the stars and arising from a combination of fundamental limitations such as Poisson statistics and any instrument noise. The noise levels attained by Kepler on-orbit exceed by some 50% the target levels for solar-type, quiet stars. We provide a decomposition of observed noise for an ensemble of 12th magnitude stars arising from fundamental terms (Poisson and readout noise), added noise due to the instrument and that intrinsic to the stars. The largest factor in the modestly higher than anticipated noise follows from intrinsic stellar noise. We show that using stellar parameters from galactic stellar synthesis models, and projections to stellar rotation, activity and hence noise levels reproduces the primary intrinsic stellar noise features.Comment: Accepted by ApJ; 26 pages, 20 figure

Platelet lamellipodium formation is not required for thrombus formation and stability

During platelet spreading, the actin cytoskeleton undergoes rapid rearrangement, forming filopodia and lamellipodia. Controversial data have been published on the role of lamellipodia in thrombus formation and stability. The Wiskott-Aldrich syndrome protein-family verprolin-homologous protein (WAVE)-regulatory complex, which has been shown in other cells to drive lamellipodium formation by enhancing actin nucleation via the actin-related protein 2/3 (Arp2/3) complex, is activated by Ras-related C3 botulinum toxin substrate 1 (Rac1) interaction with the WAVE complex subunit cytoplasmic fragile X mental retardation 1–interacting protein 1 (Cyfip1). We analyzed Cyfip1flox/floxPf4-Cre mice to investigate the role of Cyfip1 in platelet function. These mice displayed normal platelet counts and a slight reduction in platelet volume. Activation of mutant platelets was only moderately reduced to all tested agonists as measured by αIIbβ3 integrin activation and P-selectin surface exposure. However, lamellipodium formation of mutant platelets was completely abolished on different matrices. Nevertheless, Cyfip1-deficient platelets formed stable thrombi on collagen fibers ex vivo and in 2 models of occlusive arterial thrombosis in vivo. Similarly, the hemostatic function and maintenance of vascular integrity during inflammation of the skin and lung were unaltered in the mutant mice. Investigation of platelet morphology in an induced thrombus under flow revealed that platelets rather form filopodia in the thrombus shell, and are flattened with filopodium-like structures when in direct contact to collagen fibers at the bottom of the thrombus. We provide for the first time direct evidence that platelet lamellipodium formation is not required for stable thrombus formation, and that morphological changes of platelets differ between a static spreading assay and thrombus formation under flow

Teste rápido para o HIV como estratégia de prevenção da transmissão vertical no Brasil

OBJECTIVE: To assess the feasibility of HIV rapid testing for pregnant women at maternity hospital admission and of subsequent interventions to reduce perinatal HIV transmission. METHODS: Study based on a convenience sample of women unaware of their HIV serostatus when they were admitted to delivery in public maternity hospitals in Rio de Janeiro and Porto Alegre, Brazil, between March 2000 and April 2002. Women were counseled and tested using the Determine HIV1/2 Rapid Test. HIV infection was confirmed using the Brazilian algorithm for HIV infection diagnosis. In utero transmission of HIV was determined using HIV-DNA-PCR. There were performed descriptive analyses of sociodemographic data, number of previous pregnancies and abortions, number of prenatal care visits, timing of HIV testing, HIV rapid test result, neonatal and mother-to-child transmission interventions, by city studied. RESULTS: HIV prevalence in women was 6.5% (N=1,439) in Porto Alegre and 1.3% (N=3.778) in Rio de Janeiro. In Porto Alegre most of women were tested during labor (88.7%), while in Rio de Janeiro most were tested in the postpartum (67.5%). One hundred and forty-four infants were born to 143 HIV-infected women. All newborns but one in each city received at least prophylaxis with oral zidovudine. It was possible to completely avoid newborn exposure to breast milk in 96.8% and 51.1% of the cases in Porto Alegre and Rio de Janeiro, respectively. Injectable intravenous zidovudine was administered during labor to 68.8% and 27.7% newborns in Porto Alegre and Rio de Janeiro, respectively. Among those from whom blood samples were collected within 48 hours of birth, in utero transmission of HIV was confirmed in 4 cases in Rio de Janeiro (4/47) and 6 cases in Porto Alegre (6/79). CONCLUSIONS: The strategy proved feasible in maternity hospitals in Rio de Janeiro and Porto Alegre. Efforts must be taken to maximize HIV testing during labor. There is a need of strong social support to provide this population access to health care services after hospital discharge.OBJETIVO: Analizar la viabilidad de evaluación rápida del HIV entre gestantes en la admisión en la maternidad y de intervenciones para reducir la transmisión perinatal del HIV. MÉTODOS: Muestra de conveniencia de mujeres que desconocían su situación serológica para el HIV al ser admitidas para el parto en maternidades públicas de Rio de Janeiro (Sureste) y de Porto alegre (Sur de Brasil), entre marzo de 2000 y abril de 2002. Las mujeres fueron aconsejadas y evaluadas con prueba rápida Determine HIV1/2 en la maternidad. Infección por el HIV fue confirmada por el algoritmo brasilero para el diagnóstico de la infección por el HIV. La transmisión intra- útero fue determinada por el PCR-DNA-HIV. Fueron realizados análisis descriptivos de los datos sociodemográficos, número de gestaciones y de abortos previos, número de visitas de prenatal, momento de la evaluación para el HIV, resultado de la prueba rápida para el HIV, intervenciones recibidas por los recién nacidos y de transmisión vertical del HIV, de acuerdo con cada ciudad. RESULTADOS: La prevalencia de HIV entre las mujeres fue de 6,5% (N=1.439) en Porto Alegre y 1,3% (N=3,778) en Rio de Janeiro. La mayoría fue evaluada durante el trabajo de parto en Porto Alegre y en el postparto, en Rio de Janeiro. Ciento y cuarenta y cuatro niños nacieron de 143 mujeres infectadas por el HIV. Todos los recién nacidos recibieron al menos la profilaxia con zidovudina oral, excepto uno en cada ciudad. Fue posible evitar cualquier exposición a la leche materna en 96,8% y 51,1% de los recién nacidos en Porto Alegre y en Rio de Janeiro, respectivamente. La zidovudina inyectable fue administrada durante el trabajo de parto a 68,8% de los recién nacidos en Porto Alegre y 27,7% en Rio de Janeiro. Entre aquellos con muestras de sangre colectadas hasta 48 horas de nacimiento, la transmisión intra-útero fue confirmada en cuatro casos en Rio de Janeiro (4/47) y en seis casos en Porto Alegre (6/79). CONCLUSIONES: La estrategia se mostró factible en las maternidades de Rio de Janeiro y de Porto Alegre. Esfuerzos deben ser emprendidos para maximizar la evaluación durante el trabajo de parto. Fuerte soporte social precisa ser acoplado a esa estrategia para garantizar el acceso de dicha población al sistema de salud posterior a ser dado de alta de la maternidad.OBJETIVO: Analisar a viabilidade da testagem rápida para o HIV entre gestantes na admissão à maternidade e de intervenções para reduzir a transmissão perinatal do HIV. MÉTODOS: Amostra de conveniência de mulheres que desconheciam sua situação sorológica para o HIV quando admitidas para o parto em maternidades públicas do Rio de Janeiro, RJ, e de Porto Alegre, RS, entre março de 2000 e abril de 2002. As mulheres foram aconselhadas e testadas com teste rápido Determine HIV1/2 na maternidade. Infecção pelo HIV foi confirmada pelo algoritmo brasileiro para o diagnóstico da infecção pelo HIV. A transmissão intra-útero foi determinada pelo PCR-DNA-HIV. Foram realizadas análises descritivas dos dados sociodemográficos, número de gestações e de abortos prévios, número de visitas de pré-natal, momento da testagem para o HIV, resultado do teste rápido para o HIV, intervenções recebidas pelos recém-natos e de transmissão vertical do HIV, de acordo com cada cidade. RESULTADOS: A prevalência de HIV entre as mulheres foi 6,5% (N=1.439) em Porto Alegre e 1,3% (N=3.778) no Rio de Janeiro. A maioria foi testada durante o trabalho de parto em Porto Alegre e no pós-parto, no Rio de Janeiro. Cento e quarenta e quatro crianças nasceram de 143 mulheres infectadas pelo HIV. Todos os recém-natos receberam ao menos a profilaxia com zidovudina oral, exceto um em cada cidade. Foi possível evitar qualquer exposição ao leite materno em 96,8% e 51,1% dos recém-natos em Porto Alegre e no Rio de Janeiro, respectivamente. A zidovudina injetável foi administrada durante o trabalho de parto para 68,8% dos recém-natos em Porto Alegre e 27,7% no Rio de Janeiro. Entre aqueles com amostras de sangue coletadas até 48 horas do nascimento, a transmissão intra-útero foi confirmada em quatro casos no Rio de Janeiro (4/47) e em seis casos em Porto Alegre (6/79). CONCLUSÕES: A estratégia mostrou-se factível nas maternidades do Rio de Janeiro e de Porto Alegre. Esforços devem ser empreendidos para maximizar a testagem durante o trabalho de parto. Forte suporte social precisa ser acoplado a essa estratégia para garantir o acesso dessa população ao sistema de saúde após a alta da maternidade

Kepler-21b: A 1.6REarth Planet Transiting the Bright Oscillating F Subgiant Star HD 179070

We present Kepler observations of the bright (V=8.3), oscillating star HD 179070. The observations show transit-like events which reveal that the star is orbited every 2.8 days by a small, 1.6 R_Earth object. Seismic studies of HD 179070 using short cadence Kepler observations show that HD 179070 has a frequencypower spectrum consistent with solar-like oscillations that are acoustic p-modes. Asteroseismic analysis provides robust values for the mass and radius of HD 179070, 1.34{\pm}0.06 M{\circ} and 1.86{\pm}0.04 R{\circ} respectively, as well as yielding an age of 2.84{\pm}0.34 Gyr for this F5 subgiant. Together with ground-based follow-up observations, analysis of the Kepler light curves and image data, and blend scenario models, we conservatively show at the >99.7% confidence level (3{\sigma}) that the transit event is caused by a 1.64{\pm}0.04 R_Earth exoplanet in a 2.785755{\pm}0.000032 day orbit. The exoplanet is only 0.04 AU away from the star and our spectroscopic observations provide an upper limit to its mass of ~10 M_Earth (2-{\sigma}). HD 179070 is the brightest exoplanet host star yet discovered by Kepler.Comment: Accepted to Ap

Combined evaluation of sexually transmitted infections in HIV-infected pregnant women and infant HIV transmission

Background Sexually transmitted infections (STIs) including Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Treponema pallidum (TP), and cytomegalovirus (CMV) may lead to adverse pregnancy and infant outcomes. The role of combined maternal STIs in HIV mother-to-child transmission (MTCT) was evaluated in mother-infant pairs from NICHD HPTN 040. Methodology Urine samples from HIV-infected pregnant women during labor were tested by polymerase chain reaction (PCR) for CT, NG, and CMV. Infant HIV infection was determined by serial HIV DNA PCR testing. Maternal syphilis was tested by VDRL and confirmatory treponemal antibodies. Results A total of 899 mother-infant pairs were evaluated. Over 30% had at least one of the following infections (TP, CT, NG, and/or CMV) detected at the time of delivery. High rates of TP (8.7%), CT (17.8%), NG (4%), and CMV (6.3%) were observed. HIV MTCT was 9.1% (n = 82 infants). HIV MTCT was 12.5%, 10.3%, 11.1%, and 26.3% among infants born to women with CT, TP, NG or CMV respectively. Forty-two percent of HIV-infected infants were born to women with at least one of these 4 infections. Women with these infections were nearly twice as likely to have an HIV-infected infant (aOR 1.9, 95% CI 1.1-3.0), particularly those with 2 STIs (aOR 3.4, 95% CI 1.5-7.7). Individually, maternal CMV (aOR 4.4 1.5-13.0) and infant congenital CMV (OR 4.1, 95% CI 2.2-7.8) but not other STIs (TP, CT, or NG) were associated with an increased risk of HIV MTCT. Conclusion HIV-infected pregnant women identified during labor are at high risk for STIs. Co-infection with STIs including CMV nearly doubles HIV MTCT risk. CMV infection appears to confer the largest risk of HIV MTCT.NICHD (NICHD)(Brazilian AIDS Prevention Trials International Network), NIAID/ NIHNational Institute of Allergy and Infectious Diseases (NIAID)Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)National Institute of Mental Health (NIMH)Boehringer Ingelheim Pharmaceuticals Inc. (BIPI)GlaxoSmithKline, on behalf of ViiV HealthcareCepheid for the testing of CTNG in a prior HPTNUCLA Children's Discovery and Innovation Institute (CDI) through the Harry Winston Fellowship AwardUCLA AIDS InstituteUCLA Center for AIDS Research (CFAR) NIH/ NIAIDUCLA Pediatric AIDS Coalition, and WestatNIH/NICHDDavid Geffen UCLA Sch Med, Los Angeles, CA 90095 USAWestat Corp, Rockville, MD USAFundacao Oswaldo Cruz FIOCRUZ, Rio De Janeiro, RJ, BrazilUS Dept State, Off Global AIDS Coordinator, Washington, DC 20520 USAElizabeth Glaser Pediat AIDS Fdn, Washington, DC USAHosp Geral Nova Iguacu, Nova Iguacu, RJ, BrazilHosp Fed Servidores Estado, Rio De Janeiro, RJ, BrazilUniv Witwatersrand, SAMRC & Perinatal HIV Res Unit, Johannesburg, South AfricaStellenbosch Univ, Tygerberg Hosp, Cape Town, South AfricaHosp Conceicao, Porto Alegre, RS, BrazilHosp Femina, Porto Alegre, RS, BrazilIrmandade Santa Casa Misericordia Porto Alegre, Porto Alegre, RS, BrazilUniv Fed Minas Gerais, Belo Horizonte, MG, BrazilUniv Sao Paulo, Ribeirao Preto Med Sch, Sao Paulo, BrazilFdn Maternal & Infant Hlth FUNDASAMIN, Buenos Aires, DF, ArgentinaUniv Fed Sao Paulo, Escola Paulista Med, Sao Paulo, SP, BrazilEunice Kennedy Shriver Natl Inst Child Hlth & Hum, NIH, Bethesda, MD USAUCLA, Fielding Sch Publ Hlth, Los Angeles, CA USAUCSD Sch Med, La Jolla, CA USAUC Davis Sch Med, Davis, CA USABoston Univ, Sch Med, Boston, MA 02118 USAUniv Fed Sao Paulo, Escola Paulista Med, Sao Paulo, SP, BrazilNICHD (NICHD): HHSN267200800001C, N01-HD-8-0001Brazilian AIDS Prevention Trials International Network: NIAID/ NIH [U01 AI047986National Institute of Allergy and Infectious Diseases (NIAID): U01 AI068632, UM1AI068632, UM1AI068616, UM1AI106716NIMH: AI068632NG in a prior HPTN :040UCLA Center for AIDS Research (CFAR) NIH/ NIAID: AI02869, AI28697NIH/NICHD: HHSN275201300003CWeb of Scienc

A Meta-Analysis of Microarray Gene Expression in Mouse Stem Cells: Redefining Stemness

While much progress has been made in understanding stem cell (SC) function, a complete description of the molecular mechanisms regulating SCs is not yet established. This lack of knowledge is a major barrier holding back the discovery of therapeutic uses of SCs. We investigated the value of a novel meta-analysis of microarray gene expression in mouse SCs to aid the elucidation of regulatory mechanisms common to SCs and particular SC types.We added value to previously published microarray gene expression data by characterizing the promoter type likely to regulate transcription. Promoters of up-regulated genes in SCs were characterized in terms of alternative promoter (AP) usage and CpG-richness, with the aim of correlating features known to affect transcriptional control with SC function. We found that SCs have a higher proportion of up-regulated genes using CpG-rich promoters compared with the negative controls. Comparing subsets of SC type with the controls a slightly different story unfolds. The differences between the proliferating adult SCs and the embryonic SCs versus the negative controls are statistically significant. Whilst the difference between the quiescent adult SCs compared with the negative controls is not. On examination of AP usage, no difference was observed between SCs and the controls. However, comparing the subsets of SC type with the controls, the quiescent adult SCs are found to up-regulate a larger proportion of genes that have APs compared to the controls and the converse is true for the proliferating adult SCs and the embryonic SCs.These findings suggest that looking at features associated with control of transcription is a promising future approach for characterizing “stemness” and that further investigations of stemness could benefit from separate considerations of different SC states. For example, “proliferating-stemness” is shown here, in terms of promoter usage, to be distinct from “quiescent-stemness”

Validity of biomarkers of early circulatory impairment to predict outcome: a retrospective analysis

Objectives: The definition of circulatory impairment in the premature infant is controversial. Current research suggests overdiagnosis and overtreatment. We aimed to analyse which biomarkers move clinicians to initiate cardiovascular treatment (CVT). The prognostic capacity for adverse outcome (death and/or moderate-severe brain damage by cranial ultrasound at term equivalent) of these biomarkers was evaluated. Study Design: Retrospective data analysis from preterm infants enrolled in a placebo-controlled trial on dobutamine for low superior vena cava (SVC) flow, who showed normal SVC flow within the first 24 h (not randomized). Five positive biomarkers were considered: MABP 4 mmol/L; BE < −9 mmol/L; SVC flow <51 ml/kg/min. Results: Ninety eight infants formed the study cohort. Thirty six received CVT (2–95 h). Logistic regression models adjusted for gestational age showed a positive association between CVT and the risk of death or moderate-severe abnormal cranial ultrasound at term equivalent [(OR 5.2, 95%CI: 1.8–15.1) p = 0.002]. MABP 4 mmol/L were the most prevalent biomarkers at start of treatment. Low BE, high serum lactate and low SVC flow at first echocardiography showed a trend toward being associated with adverse outcome, although not statistically significant. Conclusions: Low blood pressure and high lactate are the most prevalent biomarkers used for CVT prescription. Lactic acidosis and low SVC flow early after birth showed a trend toward being associated with adverse outcome. These findings support using a combination of biomarkers for inclusion in a placebo-controlled trial on CVT during transitional circulation

A sub-Mercury-sized exoplanet

Since the discovery of the first exoplanet we have known that other planetary systems can look quite unlike our own. However, until recently we have only been able to probe the upper range of the planet size distribution. The high precision of the Kepler space telescope has allowed us to detect planets that are the size of Earth and somewhat smaller, but no previous planets have been found that are smaller than those we see in our own Solar System. Here we report the discovery of a planet significantly smaller than Mercury. This tiny planet is the innermost of three planets that orbit the Sun-like host star, which we have designated Kepler-37. Owing to its extremely small size, similar to that of Earth's Moon, and highly irradiated surface, Kepler-37b is probably a rocky planet with no atmosphere or water, similar to Mercury.Comment: Accepted and published in Nature (2013 Feb 28). This is the submitted version of paper, merged with the Supplementary Informatio