Ultrasound Core Laboratory for the Household Air Pollution Intervention Network Trial: Standardized Training and Image Management for Field Studies Using Portable Ultrasound in Fetal, Lung, and Vascular Evaluations

Ultrasound Core Laboratories (UCL) are used in multicenter trials to assess imaging biomarkers to define robust phenotypes, to reduce imaging variability and to allow blinded independent review with the purpose of optimizing endpoint measurement precision. The Household Air Pollution Intervention Network, a multicountry randomized controlled trial (Guatemala, Peru, India and Rwanda), evaluates the effects of reducing household air pollution on health outcomes. Field studies using portable ultrasound evaluate fetal, lung and vascular imaging endpoints. The objective of this report is to describe administrative methods and training of a centralized clinical research UCL. A comprehensive administrative protocol and training curriculum included standard operating procedures, didactics, practical scanning and written/practical assessments of general ultrasound principles and specific imaging protocols. After initial online training, 18 sonographers (three or four per country and five from the UCL) participated in a 2 wk on-site training program. Written and practical testing evaluated ultrasound topic knowledge and scanning skills, and surveys evaluated the overall course. The UCL developed comprehensive standard operating procedures for image acquisition with a portable ultrasound system, digital image upload to cloud-based storage, off-line analysis and quality control. Pre- and post-training tests showed significant improvements (fetal ultrasound: 71% ± 13% vs. 93% ± 7%, p < 0.0001; vascular lung ultrasound: 60% ± 8% vs. 84% ± 10%, p < 0.0001). Qualitative and quantitative feedback showed high satisfaction with training (mean, 4.9 ± 0.1; scale: 1 = worst, 5 = best). The UCL oversees all stages: training, standardization, performance monitoring, image quality control and consistency of measurements. Sonographers who failed to meet minimum allowable performance were identified for retraining. In conclusion, a UCL was established to ensure accurate and reproducible ultrasound measurements in clinical research. Standardized operating procedures and training are aimed at reducing variability and enhancing measurement precision from study sites, representing a model for use of portable digital ultrasound for multicenter field studies

Sexual behavior and drug consumption among young adults in a shantytown in Lima, Peru

<p>Abstract</p> <p>Background</p> <p>Risky sexual behaviors of young adults have received increasing attention during the last decades. However, few studies have focused on the sexual behavior of young adults in shantytowns of Latin America. Specifically, studies on the association between sexual behaviors and other risk factors for sexually transmitted infections (STI) and HIV/AIDS transmission, such as the consumption of illicit drugs or alcohol are scarce in this specific context.</p> <p>Methods</p> <p>The study participants were 393 men and 400 women between 18 and 30 years of age, from a shantytown in Lima, Peru. Data were obtained via survey: one section applied by a trained research assistant, and a self-reporting section. Logistic regression was used to estimate associations between use of any illicit drug, high-risk sexual behaviors and reported STI symptoms, adjusting for alcohol consumption level and various socio-demographic characteristics.</p> <p>Results</p> <p>Among men, age of sexual debut was lower, number of lifetime sexual partners was higher, and there were higher risk types of sexual partners, compared to women. Though consistent condom use with casual partners was low in both groups, reported condom use at last intercourse was higher among men than women. Also, a lifetime history of illicit drug consumption decreased the probability of condom use at last sexual intercourse by half. Among men, the use of illicit drugs doubled the probability of intercourse with a casual partner during the last year and tripled the probability of reported STI symptoms.</p> <p>Conclusion</p> <p>Drug consumption is associated with high-risk sexual behaviors and reported STI symptoms in a Lima shantytown after controlling for alcohol consumption level. Development of prevention programs for risky sexual behaviors, considering gender differences, is discussed.</p

Gender differences in sex-related alcohol expectancies in young adults from a peri-urban area in Lima, Peru

OBJECTIVES: To estimate the effect of sex-related alcohol expectancies (SRAE) on hazardous drinking prevalence and examine gender differences in reporting SRAE. METHODS: Trained research assistants administered part of a questionnaire to 393 men and 400 women between 18 and 30 years old from a peri-urban shantytown in Lima, Peru. The remaining questions were self-administered. Two measuring instruments-one testing for hazardous drinking and one for SRAE-were used. Multivariate data analysis was performed using logistic regression. RESULTS: Based on odds ratios adjusted for socio-demographic variables (age, marital status, education, and employment status) (n = 793), men with one or two SRAE and men with three or more SRAE were 2.3 (95% confidence interval (CI) = 1.4-3.8; p = 0.001) and 3.9 (95% CI = 2.1-7.3; p < 0.001) times more likely than men with no SRAE, respectively, to be hazardous drinkers. Reporting of SRAE was significantly higher in men versus women. CONCLUSION: In a shantytown in Lima, SRAE is associated with hazardous drinking among men, but not among women, and reporting of SRAE differs by gender

Autosome STRs in Native South America-Testing Models of Association With Geography and Language

Information on one Ecuadorian and three Peruvian Amerindian populations for 11 autosomal short tandem repeat (STR) loci is presented and incorporated in analyses that includes 26 other Native groups spread all over South America. Although in comparison with other studies we used a reduced number of markers, the number of populations included in our analyses is currently unmatched by any genome-wide dataset. The genetic polymorphisms indicate a clear division of the populations into three broad geographical areas: Andes, Amazonia, and the Southeast, which includes the Chaco and southern Brazil. The data also show good agreement with proposed hypotheses of splitting and dispersion of major language groups over the last 3,000 years. Therefore, relevant aspects of Native American history can be traced using as few as 11 STR autosomal markers coupled with a broad geographic distribution of sampled populations. Am J Phys Anthropol 145: 371-381, 2011. (C) 2011 Wiley-Liss, Inc

Gender differences in sex-related alcohol expectancies in young adults from a peri-urban area in Lima, Peru Diferencias de género en las expectativas generadas por el consumo de alcohol relacionadas con el sexo en adultos jóvenes de la periferia urbana de Lima, Perú

OBJECTIVES: To estimate the effect of sex-related alcohol expectancies (SRAE) on hazardous drinking prevalence and examine gender differences in reporting SRAE. METHODS: Trained research assistants administered part of a questionnaire to 393 men and 400 women between 18 and 30 years old from a peri-urban shantytown in Lima, Peru. The remaining questions were self-administered. Two measuring instruments-one testing for hazardous drinking and one for SRAE-were used. Multivariate data analysis was performed using logistic regression. RESULTS: Based on odds ratios adjusted for socio-demographic variables (age, marital status, education, and employment status) (n = 793), men with one or two SRAE and men with three or more SRAE were 2.3 (95% confidence interval (CI) = 1.4-3.8; p = 0.001) and 3.9 (95% CI = 2.1-7.3; p OBJETIVOS: Estimar el efecto de las expectativas generadas por el consumo de alcohol relacionadas con el sexo (SRAE) sobre la prevalencia del consumo peligroso y analizar las diferencias en la información sobre las SRAE según el género. MÉTODOS: Asistentes entrenados aplicaron parte de un cuestionario a 393 hombres y 400 mujeres de 18 a 30 años de edad residentes en un barrio marginal periurbano de Lima, Perú. Los participantes respondieron las preguntas restantes de forma individual. Se emplearon dos instrumentos de evaluación: uno sobre el consumo peligroso y otro sobre las SRAE. Se realizó un análisis multifactorial de los datos mediante regresión logística. RESULTADOS: Según las razones de posibilidades (odds ratios) ajustadas por algunas variables sociodemográficas (edad, estado marital, educación y situación laboral) (n = 793), los hombres con una o dos SRAE y los que tenían tres SRAE o más presentaron 2,3 (intervalo de confianza de 95% [IC95%]: 1,4 a 3,8; P = 0,001) y 3,9 (IC95%: 2,1 a 7,3; P < 0,001) veces más probabilidades, respectivamente, de ser bebedores peligrosos que los hombres sin SRAE. Los hombres informaron SRAE en una proporción significativamente mayor que las mujeres. CONCLUSIONES: En un barrio periférico pobre de Lima, las SRAE se asociaron significativamente con el consumo peligroso de bebidas alcohólicas en hombres, pero no en mujeres, y se observaron diferencias en la información sobre las SRAE según el género

Chronic exposure to biomass fuel smoke and markers of endothelial inflammation

Indoor smoke exposure may affect cardiovascular disease (CVD) risk via lung-mediated inflammation, oxidative stress, and endothelial inflammation. We sought to explore the association between indoor smoke exposure from burning biomass fuels and a selected group of markers for endothelial inflammation. We compared serum concentrations of amyloid A protein, E-selectin, soluble ICAM-1 and VCAM-1, von Willebrand factor (VWF), and high sensitivity C-reactive protein (hs-CRP) in 228 biomass exposed vs. 228 non-exposed participants living in Puno, Peru. Average age was 56 years (SD=13), average BMI was 26.5 kg/m(2) (SD=4.4), 48% were male, 59.4% completed high school and 2% reported a physician diagnosis of CVD. In unadjusted analysis, serum levels of soluble ICAM-1 (330 vs. 302 ng/mL; p<0.001), soluble VCAM-1 (403 vs. 362 ng/mL; p<0.001), and E-selectin (54.2 vs. 52.7 ng/mL; p=0.05) were increased in biomass exposed vs. non-exposed participants, respectively; whereas serum levels of vWF (1148 vs. 1311 mU/mL; p<0.001) and hs-CRP (2.56 vs. 3.12 mg/L; p<0.001) were decreased, respectively. In adjusted analyses, chronic exposure to biomass fuels remained positively associated with serum levels of soluble ICAM-1 (p=0.03) and VCAM-1 (p=0.05) and E-selectin (p=0.05), and remained negatively associated with serum levels of vWF (p=0.02) and hs-CRP (p<0.001). Daily exposure to biomass fuel smoke was associated with important differences in specific biomarkers of endothelial inflammation and may help explain accelerated atherosclerosis among those who are chronically exposed

DNA-Level Diversity and Relatedness of Helicobacter pylori Strains in Shantytown Families in Peru and Transmission in a Developing-Country Setting▿

The efficiency of transmission of a pathogen within families compared with that between unrelated persons can affect both the strategies needed to control or eradicate infection and how the pathogen evolves. In industrialized countries, most cases of transmission of the gastric pathogen Helicobacter pylori seems to be from mother to child. An alternative model, potentially applicable among the very poor in developing countries, where infection is more common and the sanitary infrastructure is often deficient, invokes frequent transmission among unrelated persons, often via environmental sources. In the present study, we compared the genotypes of H. pylori from members of shantytown households in Peru to better understand the transmission of H. pylori in developing-country settings. H. pylori cultures and/or DNAs were obtained with informed consent by the string test (a minimally invasive alternative to endoscopy) from at least one child and one parent from each of 62 families. The random amplified polymorphic DNA fingerprints of 57 of 81 (70%) child-mother strain pairs did not match, nor did the diagnostic gene sequences (>1% DNA sequence difference), independent of the child's age (range, 1 to 39 years). Most strains from siblings or other paired family members were also unrelated. These results suggest that H. pylori infections are often community acquired in the society studied. Transmission between unrelated persons should facilitate the formation of novel recombinant genotypes by interstrain DNA transfer and selection for genotypes that are well suited for individual hosts. It also implies that the effective prevention of H. pylori infection and associated gastroduodenal disease will require anti-H. pylori measures to be applied communitywide

Identification of New Helicobacter pylori Subpopulations in Native Americans and Mestizos From Peru

Region-specific Helicobacter pylori subpopulations have been identified. It is proposed that the hspAmerind subpopulation is being displaced from the Americans by an hpEurope population following the conquest. Our study aimed to describe the genomes and methylomes of H. pylori isolates from distinct Peruvian communities: 23 strains collected from three groups of Native Americans (Asháninkas [ASHA, n = 9], Shimaas [SHIM, n = 5] from Amazonas, and Punos from the Andean highlands [PUNO, n = 9]) and 9 modern mestizos from Lima (LIM). Closed genomes and DNA modification calls were obtained using SMRT/PacBio sequencing. We performed evolutionary analyses and evaluated genomic/epigenomic differences among strain groups. We also evaluated human genome-wide data from 74 individuals from the selected Native communities (including the 23 H. pylori strains donors) to compare host and bacterial backgrounds. There were varying degrees of hspAmerind ancestry in all strains, ranging from 7% in LIM to 99% in SHIM. We identified three H. pylori subpopulations corresponding to each of the Native groups and a novel hspEuropePeru which evolved in the modern mestizos. The divergence of the indigenous H. pylori strains recapitulated the genetic structure of Native Americans. Phylogenetic profiling showed that Orthogroups in the indigenous strains seem to have evolved differentially toward epigenomic regulation and chromosome maintenance, whereas OGs in the modern mestizo (LIM) seem to have evolved toward virulence and adherence. The prevalence of cagA + / vacA s1i1m1 genotype was similar across populations ( p = 0.32): 89% in ASHA, 67% in PUNO, 56% in LIM and 40% in SHIM. Both cagA and vacA sequences showed that LIM strains were genetically differentiated ( p < 0.001) as compared to indigenous strains. We identified 642 R-M systems with 39% of the associated genes located in the core genome. We found 692 methylation motifs, including 254 population-specific sequences not previously described. In Peru, hspAmerind is not extinct, with traces found even in a heavily admixed mestizo population. Notably, our study identified three new hspAmerind subpopulations, one per Native group; and a new subpopulation among mestizos that we named hspEuropePeru. This subpopulation seems to have more virulence-related elements than hspAmerind. Purifying selection driven by variable host immune response may have shaped the evolution of Peruvian subpopulations, potentially impacting disease outcomes

Socioeconomic and Nutritional Factors Account for the Association of Gastric Cancer with Amerindian Ancestry in a Latin American Admixed Population

<div><p>Gastric cancer is one of the most lethal types of cancer and its incidence varies worldwide, with the Andean region of South America showing high incidence rates. We evaluated the genetic structure of the population from Lima (Peru) and performed a case-control genetic association study to test the contribution of African, European, or Native American ancestry to risk for gastric cancer, controlling for the effect of non-genetic factors. A wide set of socioeconomic, dietary, and clinic information was collected for each participant in the study and ancestry was estimated based on 103 ancestry informative markers. Although the urban population from Lima is usually considered as mestizo (i.e., admixed from Africans, Europeans, and Native Americans), we observed a high fraction of Native American ancestry (78.4% for the cases and 74.6% for the controls) and a very low African ancestry (<5%). We determined that higher Native American individual ancestry is associated with gastric cancer, but socioeconomic factors associated both with gastric cancer and Native American ethnicity account for this association. Therefore, the high incidence of gastric cancer in Peru does not seem to be related to susceptibility alleles common in this population. Instead, our result suggests a predominant role for ethnic-associated socioeconomic factors and disparities in access to health services. Since Native Americans are a neglected group in genomic studies, we suggest that the population from Lima and other large cities from Western South America with high Native American ancestry background may be convenient targets for epidemiological studies focused on this ethnic group.</p> </div

Challenges in the diagnosis of paediatric pneumonia in intervention field trials: recommendations from a pneumonia field trial working group

Pneumonia is a leading killer of children younger than 5 years despite high vaccination coverage, improved nutrition, and widespread implementation of the Integrated Management of Childhood Illnesses algorithm. Assessing the effect of interventions on childhood pneumonia is challenging because the choice of case definition and surveillance approach can affect the identification of pneumonia substantially. In anticipation of an intervention trial aimed to reduce childhood pneumonia by lowering household air pollution, we created a working group to provide recommendations regarding study design and implementation. We suggest to, first, select a standard case definition that combines acute (≤14 days) respiratory symptoms and signs and general danger signs with ancillary tests (such as chest imaging and pulse oximetry) to improve pneumonia identification; second, to prioritise active hospital-based pneumonia surveillance over passive case finding or home-based surveillance to reduce the risk of non-differential misclassification of pneumonia and, as a result, a reduced effect size in a randomised trial; and, lastly, to consider longitudinal follow-up of children younger than 1 year, as this age group has the highest incidence of severe pneumonia