Venezuelan Population Research Articles

Variants may affect disease heritability

Human Genetics Huntington's disease (HD) is a late-onset neurodegenerative disease caused by the inheritance of an expansion of a trinucleotide repeat in the huntingtin ( HTT ) gene. A Venezuelan population exhibits an earlier onset of HD than is observed in individuals of European ancestry. Chao et

Decreasing prevalence of Hepatitis B and absence of Hepatitis C Virus infection in the Warao indigenous population of Venezuela.

Prevalence and molecular epidemiology studies for hepatitis B (HBV) and C (HCV) virus are scarce in Warao Amerindians from Venezuela, where an epidemic of human immunodeficiency virus type 1 (HIV-1) has recently been documented. To carry out a molecular epidemiology analysis of hepatitis B (HBV) and C (HCV) virus in Warao individuals from the Delta Amacuro State of Venezuela. A total of 548 sera were tested for serological and molecular markers for HBV and HCV. The prevalence of active infection (presence of HBV surface antigen, HBsAg), exposure to HBV (presence of Antibody to HBV core antigen, anti-HBc) and anti-HCV, was 1.8%, 13% and 0% respectively. HBV exposure was significantly lower in men below 18 years old and also lower than rates previously reported in other Amerindian communities from Venezuela. Thirty one percent (31%, 25/80) of individuals without evidence of HBV infection exhibited anti-HBs titer ≥ 10U.I / ml, being significantly more frequent in individuals younger than 20 years. A higher HBV exposure was observed among HIV-1 positive individuals (33% vs 11%, p <0.005). A high prevalence of occult HBV infection was also observed (5.6%, 11/195). Phylogenetic analysis of S gene and complete HBV genomes showed that F3 is the only circulating subgenotype, different from the F2 subgenotype found in 1991 in this population. These results suggest a recent introduction of subgenotype F3, with a low divergence among the isolates. These results highlight the importance of molecular epidemiology studies for viral control, and support the effectiveness of vaccination in reducing transmission of HBV.

Prevalencia de factores de riesgo cardiometabólico en 3 poblaciones de Venezuela: estudio VEMSOLS 2006-2010

Introduction: no previous studies had reported the prevalence of cardiometabolic diseases various regions of Venezuela. Objective: to determine the prevalence of cardiometabolic risk factors in 3 populations of Venezuela. Methods: the VEMSOLS study is a sub-national, cross-sectional, population based, with bi-stage random sampling study, evaluating 751 subjects aged 20 or older from 3 selected municipalities of Venezuela. Anthropometric and biochemical measurements were obtained. ANOVA was used to continous variables and Chi-square to proportions, a p&lt;0.05 was significant. Results: 69% were females and 81.4% from urban areas. Low HDL-c was the most prevalent disorder (63.8% [–CI- 95% 60.1-67.4]), being more common in women than in men (74.1% [69.9 -77.9] and 40.4% [33.7-43.4], respectively, p &lt; 0.05); followed by abdominal obesity (47.4% [43.8 -51.1]) and hypertriglyceridemia (45.2% [41.5 - 49.0]). One third (30.0% [26.7-33.4]) had hypertension, 11.8% (9.5 -14.5) diabetes, 23.1% (20.2-26.3) obesity, and 20.1% (17.2-23.4) elevated LDL-cholesterol. Metabolic syndrome was present in 29.9% (26.5-33.5) of the sample. Rural population from the Andeans mountains (Páramo) presented a lower prevalence of obesity and low HDL-c (p &lt; 0.05) comparing with urban samples. Lara’s population, which had the highest Body Mass Index of the 3 municipalities, had a higher prevalence of abdominal obesity, atherogenic dyslipidemia and elevated LDL-c than the other two populations (p &lt; 0.05). Conclusion: A high prevalence of cardiometabolic abnormalities in 3 populations of Venezuela was observed with a lower prevalence of alterations in the rural area. MÉD.UIS. 2018;31(1):15-22.

Non-HDL cholesterol is better than LDL-c at predicting atherosclerotic cardiovascular disease risk factors clustering, even in subjects with near-to-normal triglycerides: A report from a Venezuelan population

Background: Non-high density lipoprotein cholesterol (non-HDL-c) has emerged as an important tool in primary prevention of atherosclerotic cardiovascular disease (ASCVD), especially among those at high risk. The main objective of this study was to evaluate the predictive value of non-HDL-c for the coexistence aggregation of multiple ASCVD risk factors and compare this with LDL-c in general subjects with normal or near normal triglycerides from Maracaibo city in Venezuela. Methods: This is a descriptive, cross-sectional study with a randomized multistage sampling. 2026 subjects were selected for this study, all were adults ≥18 years old of both genders and inhabitants of Maracaibo city, Venezuela. A complete history and physical medical assessment was performed. A multivariate logistic regression model was used to determine the odds ratio (CI95%) for the coexistence of multiple risk factors for ASCVD. Results: The median (p25-p75) of non-HDL-c was 143 mg/dL (114-174 mg/dL). 52.1% (n=1056) of the sample were women, with a median of 144 mg/dL (115-174 mg/dL) among women and 143 mg/dL (114-17 4mg/dL) among men; p=0.740. Individuals ≥50 years old, smokers, those with hypertension, obesity, diabetes, high waist circumference and elevated hs-C Reactive Protein, all had higher levels of non-HDL-c. A lower median was observed among those &lt;30 years of age with elevated physical activity levels in their leisure time. Non-HDL-c between 130-159 mg/dL (OR=2.44; CI 95%=1.48-4.02; p&lt;0.001) and ≥160 mg/dL (OR=3.28; CI 95%=1.72-6.23; p&lt;0.001) was associated with greater risk of coexistent multiple risk factors for ASCVD, albeit LDL-c was not significant in the multivariate model. Conclusions: Elevated non-HDL-c was associated with conglomeration of multiple risk factors for ASCVD. This suggests evaluation of non-HDL-c may be of better utility in primary care for early identification of subjects for high risk of ASCVD. Future research might focus on the influence of non-HDL-c in cardiovascular mortality.

First record of the nymph of &lt;i&gt;Nanomis rasmusseni&lt;/i&gt; Chacon, Pescador &amp; Segnini, 2013 (Ephemeroptera: Baetidae) from Colombia

Herein, we present the first record of the nymph of Nanomis rasmusseni Chacón, Pescador &amp; Segnini, 2013, from two biogeographic regions in Colombia. This species was originally described for the Venezuelan Andes. Both Colombian and Venezuelan populations occur at high elevations, in streams with similar altitudes. We also found that both populations can be distinguished from each other by the terga II, VII, and IX coloration, in addition to the branching pattern of the abdominal gills.

Point Mutations at gyrA and gyrB Genes of Levofloxacin-Resistant Helicobacter pylori Isolates in the Esophageal Mucosa from a Venezuelan Population.

The treatment of Helicobacter pylori infection is complicated by antibiotic resistance. A high levofloxacin (LVX) resistance rate was previously demonstrated in H. pylori isolates from gastric mucosa (40%) and esophagus (19%) in individual hosts of a Venezuelan population. We aimed to assess the molecular mechanisms of LVX resistance and susceptibility in isolates from the gastroesophageal mucosa, by studying point mutations in the quinolone resistance-determining region of gyrA and gyrB genes. Sequencing of gyrA and gyrB genes (N = 120) helped to identify point mutations in 60 isolates (30 from antrum and 30 from esophagus) of five dyspeptic patients. Double (Asn87Thr and Asp91Asn) and single (Asn87Ile or Asn87Thr) mutations in the gyrA gene were identified in the esophageal mucosa. These mutations have been commonly found in the stomach. Occurrence of a single (Asn87Ile) mutation was associated with high resistance (minimum inhibitory concentration ≥ 32 μg/mL) to LVX. Only a single (Ser479Gly) mutation was found in the gyrB gene in both mucosae. One patient presented isolates with no mutations in the two genes studied. Isolates with the same mutation pattern in individual hosts revealed identical genetic profiles for these genes, confirming that isolates identified in the esophageal mucosa come from isolates colonizing the stomach. Helicobacter pylori resistance to LVX in the esophagus is related to double- and single-point mutations in gyrA and gyrB genes, such as those found in the stomach. Levofloxacin should be applied with caution, because its antibiotic effect on H. pylori is decreasing in Latin America, perhaps owing to high prescription rates.

Optimal cutoff for the evaluation of insulin resistance through triglyceride-glucose index: A cross-sectional study in a Venezuelan population.

Background: Insulin resistance (IR) evaluation is a fundamental goal in clinical and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. Methods: This is a sub-study of Maracaibo City Metabolic Syndrome Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides < 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2. Results: The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. female: 4.56±0.33, p=8.93x10 -10). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI <4.5 (2.48 vs 1.74, respectively, p<0.001). Conclusions: The TGI is a measure of interest to identify IR in the general population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

Application Of The Aace/Ace Advanced Framework For The Diagnosis Of Obesity And Cardiometabolic Disease Staging In A General Population From 3 Regions Of Venezuela: The Vemsols Study Results

To determine the prevalence of obesity according to the American Association of Clinical Endocrinologists/American College of Endocrinology (AACE/ACE) framework based on a complications-centric model with further application of the Cardiometabolic Disease Staging (CMDS) system in a Venezuelan population. A total of 1,320 adults were randomly selected from 3 regions. The AACE/ACE framework definitions were as follows: overweight, body mass index (BMI) 25 to 29.9 kg/m2 and no obesity-related complications (ORC); obesity stage 0, BMI ≥30 and no ORC; stage 1, BMI ≥25 and 1 or more mild-to-moderate ORC; and stage 2, BMI ≥25 and 1 or more severe ORC. CMDS definitions were as follows: stage 0, no metabolic syndrome (MS) components; stage 1, 1 to 2 MS components without impaired fasting glucose (IFG); stage 2, IFG or ≥3 MS components but without IFG; stage 3, IFG and MS; and stage 4, type 2 diabetes (T2D) or cardiovascular disease. The mean age was 44.8 ± 0.4 years, and 68.5% were female. The prevalence of obesity according to the AACE/ACE framework was 63.1%: overweight 3.0% (95% confidence interval [CI]: 2.1-3.9); obesity stage 0: 0.1% (0.07-0.27); obesity stage 1: 26.6% (24.2-29.0); and obesity stage 2: 36.4% (33.8-39.0). Most subjects with a BMI <25 were CMDS 0 or 1. In those with BMI ≥ 25, only 4.6% were CMDS 0. The prevalence of obesity according to the World Health Organization (WHO, BMI ≥30) was 29.3% (24.7-33.7). In a general population study, applying the AACE/ACE framework for obesity and CMDS increased the detection of ORC and therefore higher risk subjects compared to classic anthropometric measurements. AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; BMI = body mass index; CMDS = Cardiometabolic Disease Staging; DALY = disability-adjusted life years; LA = Latin America; MS = metabolic syndrome; ORC = obesity-related complications; WC = waist circumference; WHO = World Health Organization.

Influencia de la depresión, los estilos de comunicación y la adhesión al tratamiento sobre los niveles de glucosa en personas con diabetes

The aim of the present research was to analyze the influence of depression, passive-assertive-aggressive communication styles and adherence to treatment over the glucose levels of subjects with Type 2 diabetes mellitus. Participants were 278 patients with a minimum of one year of having been diagnosed, selected through a purposive non-probability sampling, with ages ranging from 19 to 77 years old, with no amputations, nor comorbidity with nephropathy or diabetic retinopathy. A non-experimental investigation was developed through a cross-sectional design, establishing relationships between variables in a path analysis through multiple regression analyses. The instruments used were the Cuestionario Tridimensional para la Depresion (CTD, for its Spanish acronym) [Three-Dimensional Questionnaire for Depression]; the Autoinformes de Actitudes y Valores en las Interacciones Sociales (ADCAS, for its Spanish acronym) [Self Reports of Attitudes and Values in Social Interactions], and the Instrumento para Medir el Estilo de Vida en Diabeticos (IMEVID, for its Spanish acronym) [Instrument to Measure Diabetic Lifestyles] used to evaluate adherence to treatment. All of these instruments had been validated for the Venezuelan population. In addition, HbA1c was used to measure glucose level. Significant correlations between variables demonstrated to be low (oscillating between r -0.12 and r -0.33), except for two of them considered to be moderate (depression-assertive communication r -0,47 <p 0,05; and aggressive communication-assertive communication r -0,44 <p 0,05). Likewise, from the path analysis, it could be seen that none of the variables were statistically significant for the prediction of glucose levels. In regards to treatment adherence, the variable that contributed the most to the prediction was depression. Concerning the communication styles, negative, moderate and significant associations were observed between depression and assertiveness. No relationship was found between depression and aggressiveness and passiveness. In conclusion, only two of the established relationships through the path analysis were corroborated. Confirmation of these findings is suggested for future investigations.

Coup‐Proofing and Beyond: The Regime‐Survival Strategies of Hugo Chávez

After a long history of domestic political and economic instability, rampant corruption, and income inequality, former Venezuelan President Hugo Chávez entered the political arena in 1998, touting a campaign for change. After winning the presidency by a landslide in 1999, Chávez began to implement a series of policies that changed Venezuela forever. The elimination of presidential term limits was perhaps one of the most‐controversial moves that Chávez made during his presidency. Despite significant backlash from the Venezuelan population and protest by the opposition, Chávez remained in office for almost 14 years. This article explores the Chávez presidency from 1999–2013, concluding that his political longevity can be attributed to a series of regime‐survival strategies and coup‐proofing techniques implemented during his time in office.

Optimal cutoff for the evaluation of insulin resistance through triglyceride-glucose index: A cross-sectional study in a Venezuelan population

Background: Insulin resistance (IR) evaluation is a fundamental goal in clinical and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. Methods: This is a sub-study of Maracaibo City Metabolic Syndrome Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides &lt; 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2. Results: The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. female: 4.56±0.33, p=8.93x10-10). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI &lt;4.5 (2.48 vs 1.74, respectively, p&lt;0.001). Conclusions: The TGI is a measure of interest to identify IR in the general population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

Venezuela's melting pot: 1500-1800

Not much is known about the demography of the native population of Venezuela in Colonial times. Until mid-17th century, some factual information may be gained from the narratives of the first conquistadores, missionaries and colonists, as well as of authors writing in later times of the Colony, but with access to original sources. After mid-17th century, some quantitative information of demographic relevance was collected by the Jesuit, Capuchin and Franciscan missionaries and, in the last decades of the 18th century, by the colonial administration and the religious authorities. The native population declined, from between 200,000 and 500,000 inhabitants at contact (guesstimates of modern authors) to perhaps 120,000 in 1800, according to Humboldt’s estimate. It is possible that the initial decline became steeper after the first smallpox pandemic of the 1580s and continued, at a slower pace, until the Independence. As in other regions of South America, marriage was early and almost universal, and the high ratio of births to deaths seems to indicate a high potential for growth, interrupted by frequent mortality crisis.A competing cause of the decline of the natives was the process of mestizaje that intensified with the increase of the population of European and African origin.

Optimal cutoff for the evaluation of insulin resistance through triglyceride-glucose index: A cross-sectional study in a Venezuelan population

Background: Insulin resistance (IR) evaluation is a fundamental goal in clinical and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. Methods: This is a sub-study of Maracaibo City Metabolic Syndrome Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides < 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2. Results: The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. female: 4.56±0.33, p=8.93x10 -10). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI <4.5 (2.48 vs 1.74, respectively, p<0.001). Conclusions: The TGI is a measure of interest to identify IR in the general population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

Optimal cutoff for visceral adiposity index in a Venezuelan population: Results from the Maracaibo City Metabolic Syndrome Prevalence Study

AimVisceral obesity is one of the most intensely researched cardiometabolic risk factors in recent years; nonetheless, its accurate assessment remains a challenge in regions were socioeconomic conditions hinder the widespread use of diagnostic methods for this purpose, such as imaging tests. In this setting, Visceral Adiposity Index (VAI) may be a useful tool. Thus, the objective of this study was to determine the VAI cutoff in adult population from Maracaibo City, Venezuela. MethodsThis is a descriptive, cross-sectional study with multi-staged sampling; 2026 subjects of both genders aged ≥18 years were selected from this database and had their VAI calculated. In order to determine VAI cutoffs, subsamples of metabolically healthy and sick individuals were determined, with 599 and 286 subjects, respectively. Gender-specific and general ROC curves were plotted in order to identify the most suitable cutoff according to sensitivity and specificity. ResultsMedian VAI in the selected sample was 1.67 (0.97–2.78). The optimal cutoff was determined to be 1.91, with 70.3% sensitivity, 70.3% specificity [AUC=0.777 (0.745–0.808)]. No differences were found between genders. Analysis by age revealed VAI to have greater predictive power among subjects aged<30 years (cutoff: 1.53), 78.6% sensitivity, 72.8% specificity [AUC=0.797 (0.709–0.884)]. ConclusionWe suggest a VAI cutoff of 1.9 for define dysfunctional adiposity in our population, with age being an important factor in the epidemiologic behavior of this variable, particularly in younger individuals.

Optimal cutoff for the evaluation of insulin resistance through triglyceride-glucose index: A cross-sectional study in a Venezuelan population.

Background: Insulin resistance (IR) evaluation is a fundamental goal in clinical and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. Methods: This is a sub-study of Maracaibo City Metabolic Syndrome Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides < 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2. Results: The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. female: 4.56±0.33, p=8.93x10 -10). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI <4.5 (2.48 vs 1.74, respectively, p<0.001). Conclusions: The TGI is a measure of interest to identify IR in the general population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

Tracking the return of Aedes aegypti to Brazil, the major vector of the dengue, chikungunya and Zika viruses.

BackgroundAedes aegypti, commonly known as “the yellow fever mosquito”, is of great medical concern today primarily as the major vector of dengue, chikungunya and Zika viruses, although yellow fever remains a serious health concern in some regions. The history of Ae. aegypti in Brazil is of particular interest because the country was subjected to a well-documented eradication program during 1940s-1950s. After cessation of the campaign, the mosquito quickly re-established in the early 1970s with several dengue outbreaks reported during the last 30 years. Brazil can be considered the country suffering the most from the yellow fever mosquito, given the high number of dengue, chikungunya and Zika cases reported in the country, after having once been declared “free of Ae. aegypti”.Methodology/Principal findingsWe used 12 microsatellite markers to infer the genetic structure of Brazilian Ae. aegypti populations, genetic variability, genetic affinities with neighboring geographic areas, and the timing of their arrival and spread. This enabled us to reconstruct their recent history and evaluate whether the reappearance in Brazil was the result of re-invasion from neighboring non-eradicated areas or re-emergence from local refugia surviving the eradication program. Our results indicate a genetic break separating the northern and southern Brazilian Ae. aegypti populations, with further genetic differentiation within each cluster, especially in southern Brazil.Conclusions/SignificanceBased on our results, re-invasions from non-eradicated regions are the most likely scenario for the reappearance of Ae. aegypti in Brazil. While populations in the northern cluster are likely to have descended from Venezuela populations as early as the 1970s, southern populations seem to have derived more recently from northern Brazilian areas. Possible entry points are also revealed within both southern and northern clusters that could inform strategies to control and monitor this important arbovirus vector.

Arterial hypertension and determinants in Venezuela

To determine the prevalence and determinants of arterial hypertension in the Venezuelan population. A systematic review of the literature was performed in the PubMed and LILACS databases. The inclusion criteria were hypertension, Venezuela and risks. Articles published in any language were chosen, with no time limit. Out of 90 articles found during the search, only 20 met the inclusion criteria. Most of the data come from studies conducted in the central region of the country. The prevalence of hypertension found in the rural area is 33 %, while it oscillates between 24 and 31 % in the urban area, and 2.5 % in children. The studies showed that modifiable determining factors include obesity and dyslipidemias. In turn, non-modifiable factors include family history, race and age. Data are insufficient to establish the prevalence of the disease in Venezuela and its determinants. It is recommended to encourage multicenter prevalence studies that cover the entire country. Studies should be regularly done over time (longitudinal studies) to describe the increase or not in prevalence.

Determinantes de la pobreza en Venezuela y Colombia: estudio comparativo 2010-2014

This paper´s objective is to evaluate and compare the main microeconomic determinants of poverty in Venezuela and Colombia for the 2010-2014 period. Using information from Household Surveys by Sampling and the Great Integrated Household Survey, poverty level estimations are obtained through a binomial logit model using the maximum likelihood method. Results show similarities in the poverty determinants for both countries. These results evidence that the probability of being poor is higher in Venezuela than in Colombia. In particular, for 2014 the probabilities are close to one, what might reveal the generalized impoverishment in the Venezuelan population, while in Colombia the probability of being poor is less, which can be a stability indicator of the economic growth witnessed in the last years.

Multiple cag genotypes of Helicobacter pylori isolates colonize the oesophagus in individual hosts in a Venezuelan population.

Multiple Helicobacter pylori strains colonize and coexist in the stomach of one single patient, carrying heterogeneous distributions of cag genotypes. The oesophagus provides a niche for H. pylori colonization; however, little is known about its adaptive role. Using PCR for cagA, cagE and virB11 genes from cag-pathogenicity island (PAI) and Etest for antimicrobial susceptibility test, we determined cag-PAI genotypes associated with H. pylori virulence, when positive cultures were matching in both the stomach and the oesophagus (96 isolates; 8 out of 80 dyspeptic patients). The stomach showed complete cag-PAI islands in 77 % of the isolates, whereas the oesophagus showed complete cag-PAI islands only in 44 % of the isolates. Expression of CagA and interleukin 8 correlated with inflammatory processes and histopathological changes in the stomach, but not in the oesophagus. Different cag-PAI profiles were found in both mucosae of an individual host, and at least one oesophagus profile corresponded to one profile identified in stomach. The antibiotic resistance profiles showed variability in the colonization by single or mixed H. pylori isolates in the gastric and oesophageal mucosa both intra- and inter-individuals. These results demonstrate colonization with multiple H. pylori isolates in the oesophageal mucosa, like those found in the stomach of individual hosts. H. pylori was characterized by a dominant partial island, low interleukin 8 induction with lower histopathological damage and lower antibiotic resistance, suggesting that the microenvironmental changes in individual hosts select less virulent isolates in the oesophagus than in the stomach. New approaches to ensure effective eradication therapy in multi-resistant H. pylori strains must be developed.

A reassessment of the vocalization and distribution of Scinax exiguus (Duellman, 1986) (Anura: Hylidae) in the Amazonian savanna of Roraima, northern Brazil, with the description of its aggressive call

Scinax exiguus was described from the Gran Sabana, southeastern Venezuela, and its distribution is associated with the one Amazonian savanna region in northern South America. Herein, we describe the aggressive call and redescribe the advertisement call of S. exiguus, including recordings from the type locality. Also, we report on intraspecific variation between Venezuelan and Brazilian populations and we make remarks on its distribution in Brazil. Advertisement calls from the type locality (Bolívar, Venezuela) mainly differ in temporal traits from those of the two Brazilian populations, especially in duration and pulse organization. In contrast, calls from both Brazilian populations had remarkable differences from each other in the dominant frequency. Body size also varied between the type series (Venezuela) and a Brazilian population. We suggest that the acoustic variation in S. exiguus might be explained partly by differences in temperature and varying degrees of motivational state of calling males. One of our study sites (Cantá, Roraima) now represents the southernmost record for the species in comparison to the previous record (Boa Vista). Additional research and conservation measures are required in the Guyanan savanna in northern South America for the protection of its endemics.