Seroprevalence of viral and bacterial pathogens among malaria patients in an endemic area of southern Venezuela.

BACKGROUND: Malaria remains a leading public health problem worldwide. Co-infections with other pathogens complicate its diagnosis and may modify the disease's clinical course and management. Similarities in malaria clinical presentation with other infections and overlapping endemicity result in underdiagnosis of co-infections and increased mortality. Thus, the aim of this study was to determine the seroprevalence of viral and bacterial pathogens among diagnosed malaria patients in malaria-endemic areas in Venezuela. METHODS: A cross-sectional study was conducted on malaria patients attending three reference medical centres in Ciudad Bolivar, Venezuela. Clinical evaluation and laboratory tests for dengue virus (DENV), chikungunya virus (CHIKV), viral hepatitis [hepatitis A virus (HAV), hepatitis B virus (HBV), and hepatitis C virus (HCV)], and leptospirosis (LEP) were performed by enzyme-linked immunosorbent assays. Previous exposure to these pathogens was defined by the presence of specific immunoglobulin (Ig) G, and co-infection or recent exposure (CoRE) was determined by the presence of specific IgM alone or IgM + IgG. Data analysis considered descriptive statistics. Parameter distribution was statistically evaluated using Kolmogorov-Smirnov test and the necessary comparison tests. Odds ratio (OR) for complications was determined according to CoRE presence with a 95% confidence interval (CI). RESULTS: A total of 161 malaria patients were studied, 66% infected with Plasmodium vivax, 27% with P. falciparum, and 7.5% harboured P. vivax/P. falciparum mixed infection. Previous exposure to DENV (60%) and CHIKV (25%) was frequent. CoRE was confirmed in 55 of the 161 malaria patients (34%) and were more frequent in P. falciparum (49%) than in P. vivax (29%) and mixed malaria patients (25%) (OR = 2.43, 95% CI: 1.39-4.25, P = 0.018). The most frequent CoRE was DENV (15%), followed by HAV (12%), HBV (6.2%), CHIKV (5.5%), and LEP (3.7%); HCV CoRE was absent. Complicated malaria was significantly more frequent in patients with CoRE (56%) than those without CoRE (36%; OR = 2.31, 95% CI: 1.18-4.92, P = 0.013). CONCLUSIONS: We found high CoRE prevalence in malaria patients as determined by serology in the study region; cases were associated with a worse clinical outcome. Further prospective studies with samples from different infection sites and the use of molecular tools are needed to determine the clinical significance of these findings.

Sub-lineages of the Omicron variant of SARS-CoV-2: characteristic mutations and their relation to epidemiological behavior / Sub-linajes de la variante Ómicron del SARS-CoV-2: mutaciones características y su relación con el comportamiento epidemiológico

Abstract By the end of 2021, the Omicron variant of SARS-CoV-2, the coronavirus responsible for COVID-19, emerges, causing immediate concern, due to the explosive increase in cases in South Africa and a large number of mutations. This study describes the characteristic mutations of the Omicron variant in the Spike protein, and the behavior of the successive epidemic waves associated to the sub-lineages throughout the world. The mutations in the Spike protein described are related to the virus ability to evade the protection elicited by current vaccines, as well as with possible reduced susceptibility to host proteases for priming of the fusion process, and how this might be related to changes in tropism, a replication enhanced in nasal epithelial cells, and reduced in pulmonary tissue; traits probably associated with the apparent reduced severity of Omicron compared to other variants.

Resumen A finales de 2021 surge la variante Omicron del SARS-CoV-2, el coronavirus responsable de la COVID-19, causando preocupación inmediata, debido al aumento explosivo de casos en Suráfrica, y a su gran cantidad de mutaciones. Este estudio describe las mutaciones características de la variante Ómicron en la proteína de la Espiga (S) y el comportamiento de las sucesivas olas epidémicas asociadas a la circulación de sus sub-linajes en todo el mundo. Las mutaciones en la proteína S descritas están relacionadas con su capacidad para evadir la protección provocada por las vacunas actuales, así como su posible susceptibilidad reducida a las proteasas del hospedero para la preparación del proceso de fusión. Se infiere cómo esto podría estar relacionado con su cambio en el tropismo, con una replicación mayor en las células epiteliales nasales y menor en el tejido pulmonar, rasgos probablemente asociados a su aparente menor gravedad en comparación con otras variantes.

Description of a One-Year Succession of Variants of Interest and Concern of SARS-CoV-2 in Venezuela.

Some of the lineages of SARS-CoV-2, the new coronavirus responsible for COVID-19, exhibit higher transmissibility or partial resistance to antibody-mediated neutralization and were designated by WHO as Variants of Interests (VOIs) or Concern (VOCs). The aim of this study was to monitor the dissemination of VOIs and VOCs in Venezuela from March 2021 to February 2022. A 614 nt genomic fragment was sequenced for the detection of some relevant mutations of these variants. Their presence was confirmed by complete genome sequencing, with a correlation higher than 99% between both methodologies. After the introduction of the Gamma VOC since the beginning of the year 2021, the variants Alpha VOC and Lambda VOI were detected as early as March 2021, at a very low frequency. In contrast, the Mu VOI, detected in May 2021, was able to circulate throughout the country. After the detection of the Delta VOC in June 2021, it became the predominant circulating variant. With the arrival of the Omicron VOC in December, this variant was able to displace the Delta one in less than one month.

Detection of the Omicron variant of SARSCoV-2 by restriction analysis targeting the mutations K417N and N440K of the spike protein / Detección de la Variante Ómicron del SARS-CoV-2 por análisis de restricción de dos mutaciones de la proteína de la espiga

Abstract By the end of 2021, the Omicron variant of concern (VOC) emerges in South Africa. This variant caused immediate concern, due to the explosive increase in cases associated with it and the large number of mutations it exhibits. In this study, the restriction sites that allow detecting the mutations K417N and N440K in the Spike gene are described. This analysis allows us to propose a rapid method for the identification of cases infected with the Omicron variant. We show that the proposed methodology can contribute to provide more information on the prevalence and rapid detection of cases of this new VOC.

Resumen Para finales de 2021 surge la variante de preocupación (VOC por sus siglas en inglés) Ómicron en Sudáfrica. Esta variante causó de forma inmediata preocupación, debido al aumento explosivo de casos asociados a ella y al gran número de mutaciones que exhibe. En este estudio, se describen los sitios de restricción que permiten detectar dos de estas mutaciones en el gen de la espiga, las mutaciones K417N y N440K. Este análisis permite proponer un método rápido para la identificación de casos infectados con la variante Ómicron. Mostramos que la metodología propuesta puede contribuir a proporcionar más información sobre la prevalencia y a detectar rápidamente los casos de esta nueva VOC.

Introduction and rapid dissemination of SARS-CoV-2 Gamma Variant of Concern in Venezuela.

In less than two years since SARS-CoV-2 emerged, the new coronavirus responsible for COVID-19, has accumulated a great number of mutations. Many of these mutations are located in the Spike protein and some of them confer to the virus higher transmissibility or partial resistance to antibody mediated neutralization. Viral variants with such confirmed abilities are designated by WHO as Variants of Concern (VOCs). The aim of this study was to monitor the introduction of variants and VOCs in Venezuela. A small fragment of the viral genome was sequenced for the detection of the most relevant mutations found in VOCs. This approach allowed the detection of Gamma VOC. Its presence was confirmed by complete genome sequencing. The Gamma VOC was detected in Venezuela since January 2021, and in March 2021 was predominant in the East and Central side of the country, representing more than 95% of cases sequenced in all the country in April-May 2021. In addition to the Gamma VOC, other isolates carrying the mutation E484K were also detected. The frequency of this mutation has been increasing worldwide, as shown in a survey of sequences carrying E484K mutation in GISAID, and was detected in Venezuela in many probable cases of reinfection. Complete genome sequencing of these cases allowed us to identify E484K mutation in association with Gamma VOC and other lineages. In conclusion, the strategy adopted in this study is suitable for genomic surveillance of variants for countries lacking robust genome sequencing capacities. In the period studied, Gamma VOC seems to have rapidly become the dominant variant throughout the country.

The clinical-epidemiological profile of malaria patients from Southern Venezuela, a critical hotspot in Latin America.

BACKGROUND: Venezuela accounted for 55% of the cases and 73% of the malaria deaths in the Americas in 2019. Bolivar state, in the southeast, contributes > 60% of the country's Plasmodium vivax and Plasmodium falciparum cases every year. This study describes the clinical-epidemiological characteristics of clinical malaria patients in this high-transmission area. METHODS: A prospective study was conducted on patients seeking medical attention in three medical centres in the state capital, Ciudad Bolivar, between June and October 2018. Malaria diagnosis was carried out using microscopy following national standards. Malaria-positive patients were examined for clinical symptoms, and haematological tests were performed at the time of diagnosis. Patients were followed up by telephone to evaluate malaria recurrences. RESULTS: Out of 287 patients, 200 (69.7%) were positive for P. vivax, 69 (24%) for P. falciparum, and 18 (6.3%) had mixed (P. vivax/P. falciparum) infections. Patients' median age was 33 years (IQR 20), 168 (69%) were men, and 40% practiced gold mining as the main occupation. Fever (96.5%), chills (91.3%), and headaches (90.6%) were the most frequent symptoms. At least one symptom associated with severe malaria was observed in 69 out of 161 patients with complete clinical evaluation (42.9%). Plasmodium vivax infections were found in 42 out of 69 (60.9%) severe cases; by contrast, P. falciparum and mixed malaria caused 34.8% (24/69) and 4.4% (3/69) of infections, respectively. Two patients died of cerebral malaria. Mean hemoglobin was lower in the patients infected with P. falciparum than those infected with P. vivax. Regardless of the parasite causing the infection, patients presented high levels of total bilirubin, aminotransferases (AST, ALT), and lactate dehydrogenase (LDH). Out of the 142 patients followed up by phone for three months (49.5% of the 287 patients), 35 (24.7%) reported recurrences. CONCLUSIONS: The high malaria prevalence among young male adults practicing gold mining suggests that this occupation is a significant risk factor. The unexpected high prevalence of P. vivax patients with at least one criteria of severe clinical disease is a matter of concern. Whether it is the result of a lack of timely diagnosis and effective treatment should be explored.

Asociación del peso al nacer con adiposidad en niños escolares de distintas regiones de argentina / Association of birth weight with adiposity in school children from different regions of argentina

Introducción: diversos estudios han sugerido que el bajo y alto peso al nacer (PN) se asocian a obesidad (OB) y sobrepeso (SP) durante la infancia y la edad adulta. Objetivos: determinar la asociación entre PN y OB en escolares de 9 años de tres regiones de Argentina. Materiales y métodos: las medidas antropométricas y la presión arterial (PA) se tomaron en 1.131 escolares (505 masculinos) de 8,8±2,1 años de edad promedio, en tres regiones de Argentina durante el año 2019. Se interrogó, además, acerca del peso al nacer y el estilo de vida. Resultados: el 21,1% (239) de los niños presentaba SP (IMC>85 <95 percentilo según CDC) y el 21,8% (246) OB (IMC>95 percentilo). La prevalencia de PN bajo (<2.500 g) fue de fue de 6,2% (n=70) y de PN alto (>4.000 g) de 7,3% (n=82). El puntaje z-IMC de los niños de 9 años aumentaba significativamente con el aumento del PN: PN bajo (z-IMC=0,33), normal (z-IMC=0,72) y alto (z-IMC=1,12). En modelos de regresión logística múltiple se observó que el PN bajo se asoció inversamente a la OB (OR, 0.41 [IC del 95%: 0,19-0,92]), mientras que el PN alto se asoció directamente con la OB ajustado por edad y sexo (OR, 2.48 [95% IC 1,53-4,02]). Conclusiones: nuestros datos indican que el alto PN, pero no el bajo PN, se asocia con OB en niños en edad escolar de 9 años, mientras que el bajo PN está inversamente asociado con OB.

Introduction: several studies have suggested that low and high birth weight are associated with obesity (OB) and overweight (OW) during childhood and adulthood. Objectives: to determine the association between birth weight and OB in 9-year-old schoolchildren from three areas of Argentina. Materials and methods: anthropometric measurements and blood pressure (BP) were taken in 1.131 schoolchildren (505 males) of an average age of 8.8±2.1 years in three areas of Argentina during 2019. Mothers were asked about their children's birth weight and lifestyle. Results: 21.1% (239) of the children had OW (BMI>85 <95 percentile according to the CDC) and 21.8% (246) OB (BMI>95 percentile). The prevalence of low birth weight (<2.500 g) was 6.2% (n=70) and of high birth weight (>4.000 g) was 7.3% (n=82). The 9-year-old z-BMI score increased significantly with increasing birth weight: low birth weight (z-BMI=0.33), normal (z-BMI=0.72) and high (z-BMI=1.12). In multiple logistic regression models, it was found that low birth weight was inversely associated with OB (OR, 0.41 [95% CI: 0.19-0.92]), while high birth weight was directly associated with OB adjusted for age and sex (OR, 2.48 [95% CI 1.53-4.02]). Conclusions: our data indicate that high birth weight, but not low birth weight, is associated with OB in 9-year-old schoolchildren, while low birth weight is inversely associated with OB

COVID-19: la lucha invisible contra la ignorancia y el estigma / No disponible

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Non-high-density lipoprotein cholesterol curves in Argentinean indigenous children living at high altitude and US children.

OBJECTIVE: To describe the non-high-density lipoprotein cholesterol (non-HDL-C) as mean and percentiles by age and sex in Argentinean indigenous schoolchildren living at 3750 m, contrasting these estimates with those reported in the 2011-2012 National Center for Health Statistics reference population (NHANES). METHODS: Non-HDL-C was calculated as total cholesterol-HDL-C. Analyses incorporated sampling weights for age and sex to obtain unbiased estimates. Sex- and age-specific smoothed percentile curves were performed with Cole's LMS method. RESULTS: A total of 236 (49% males) children from San Antonio de los Cobres (SAC) were evaluated twice and compared with 1409 NHANES children. Non-HDL-C values were 4 mg/dL higher in SAC than in NHANES (109 vs 105 mg/dL, respectively). Trends in non-HDL-C 50th percentile in females differed between ages 6 to 7 and 8 years; in SAC non-HDL-C decreased from 111 to 104 mg/dL, NHANES levels remained stable from103 to 104 mg/dL. Among children aged 9 to10 years, non-HDL-C increased from 114 mg/dL to 117 mg/dL in SAC, but decreased from 113 to 107 mg/dL in NHANES. Between ages 12 and 13 years, non-HDL-C increased from 108 to 120 mg/dL in SAC, and remained steady from105 to 106 mg/dL in NHANES. The 50th percentile of non-HDL-C in males showed similar trends except for ages 6 to 7 to age 8 when non-HDL-C remained stable from 106 to 107 mg/dL in SAC, and increased from 98 mg/dL to 104 mg/dL in NHANES. CONCLUSIONS: Non-HDL-C levels in children vary with age, sex, ethnicity, and altitude. Different patterns in non-HDL-C were observed for girls in SAC compared with NHANES. However, more stable patterns were observed in boys in both groups.

Type 2 diabetes markers in indigenous Argentinean children living at different altitudes.

BACKGROUND: Exposure to hypoxia at high altitude is increasingly being recognized as a risk factor for metabolic diseases. OBJECTIVE: To determine the association between Type 2 diabetes (T2D) risk factors and altitude in two groups of Argentinean indigenous schoolchildren who live permanently at different altitudes. METHODS: This cross-sectional study compared 142 schoolchildren from San Antonio de los Cobres (SAC), 3750 m above sea level, with 171 from Chicoana (CH), 1400 m. Data for children's anthropometry, blood pressure and lipids, as well as mothers' height and weight were assessed. RESULTS: There was not a significant difference in age between SAC (9.0 + 2y) and CH (9.4 + 2y) children. However, mean children's weight (29 vs. 38 kg), height (130 vs. 138 cm), BMI (17 vs. 19 kg/m2), and HDL-C (46 vs. 48 mg/dL) were significantly lower in SAC than in CH, respectively. In contrast, systolic blood pressure (87 vs. 70 mmHg), cholesterol (157 vs. 148 mg/dL), and triglycerides (104 vs. 88 mg/dL) were significantly higher in SAC than in CH, respectively. There was not a significant difference in age (33.2 + 7y vs. 34.4 + 8y) and BMI (26.2 + 4y vs. 28 + 5y) between SAC and CH mothers. Multiple linear regression analyses showed that children's blood pressure (R2 = 0.38), triglycerides (R2 = 0.21), and HDL-C (R2 = 0.16) were significantly associated with altitude, adjusted for confounding variables. CONCLUSION: This study shows that indigenous Argentinean children living at 3750 meters have higher T2D risk compared with those living at 1400 meters above sea level.

Comparison Between HDL-C Levels in Argentine Indigenous Children Living at High Altitudes and U.S. Children.

BACKGROUND: Studies have shown low levels of high-density lipoprotein cholesterol (HDL-C) in indigenous children versus urban children from Argentina. We hypothesized that indigenous children living at high altitudes might have lower HDL-C levels compared with U.S. children, probably due to ambient hypoxia, lifestyle conditions, or ethnicity. This study was designed (1) to compare HDL-C levels in Argentinean indigenous children with those reported in the 2011-2012 National Health and Nutrition Examination Survey (NHANES) for U.S. children and (2) to determine the association between HDL-C and adiposity in both groups. SUBJECTS AND METHODS: A cross-sectional study of 1,232 (631 females) Argentinean indigenous schoolchildren (4-14 years old) from San Antonio de los Cobres (SAC) was performed between November 2011 and November 2014. Anthropometric measures were performed in the whole group and compared with those of 2,151 U.S. children (1,034 females). However, HDL-C concentrations were measured in 905 SAC children and compared with those of 1,451 U.S. children. Analyses were done incorporating sampling weights for age in both samples to obtain unbiased estimates. In the case of NHANES the weights provided by each individual in the 2011-2012 NHANES demographic file were used, whereas in the SAC sample the weights were obtained using the census data provided by the 2010 National Statistics and Censuses Institute of Argentina. RESULTS: The prevalence of overweight/obesity was significantly lower in SAC (135/1,232; 11%) than in the United States (759/2,151; 35%). However, the prevalence of low levels of HDL-C was significantly higher in SAC (298/905; 33%) than in the United States (142/1,451; 10%). The prevalence of low levels of HDL-C increased significantly in both groups as body mass index categories increased. Multiple logistic regression analysis showed that SAC children had nine and a half times the odds of having low levels of HDL-C compared with U.S. children, adjusted for confounding variables (odds ratio = 9.55; 95% confidence interval, 7.18-12.71). CONCLUSIONS: This study shows a high prevalence of low levels of HDL-C in indigenous Argentinean children 4-14 years of age living at high altitudes compared with U.S. children.

Prevalence and molecular characterization of G6PD deficiency in two Plasmodium vivax endemic areas in Venezuela: predominance of the African A-(202A/376G) variant.

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency causes acute haemolytic anaemia triggered by oxidative drugs such as primaquine (PQ), used for Plasmodium vivax malaria radical cure. However, in many endemic areas of vivax malaria, patients are treated with PQ without any evaluation of their G6PD status. METHODS: G6PD deficiency and its genetic heterogeneity were evaluated in northeastern and southeastern areas from Venezuela, Cajigal (Sucre state) and Sifontes (Bolívar state) municipalities, respectively. Blood samples from 664 randomly recruited unrelated individuals were screened for G6PD activity by a quantitative method. Mutation analysis for exons 4-8 of G6PD gen was performed on DNA isolated from G6PD-deficient (G6PDd) subjects through PCR-RFLP and direct DNA sequencing. RESULTS: Quantitative biochemical characterization revealed that overall 24 (3.6%) subjects were G6PDd (average G6PD enzyme activity 4.5 ± 1.2 U/g Hb, moderately deficient, class III), while DNA analysis showed one or two mutated alleles in 19 of them (79.2%). The G6PD A-(202A/376G) variant was the only detected in 17 (70.8%) individuals, 13 of them hemizygous males and four heterozygous females. Two males carried only the 376A → G mutation. No other mutation was found in the analysed exons. CONCLUSIONS: The G6PDd prevalence was as low as that one shown by nearby countries. This study contributes to the knowledge of the genetic background of Venezuelan population, especially of those living in malaria-endemic areas. Despite the high degree of genetic mixing described for Venezuelan population, a net predominance of the mild African G6PD A-(202A/376G) variant was observed among G6PDd subjects, suggesting a significant flow of G6PD genes from Africa to Americas, almost certainly introduced through African and/or Spanish immigrants during and after the colonization. The data suggest that 1:27 individuals of the studied population could be G6PDd and therefore at risk of haemolysis under precipitating factors. Information about PQ effect on G6PDd individuals carrying mild variant is limited, but since the regimen of 45 mg weekly dose for prevention of malaria relapse does not seem to be causing clinically significant haemolysis in people having the G6PD A-variant, a reasoned weighing of risk-benefit for its use in Venezuela should be done, when implementing public health strategies of control and elimination.

Healthier Lipid Profiles with Vitamin D Supplementation in a Pilot Study in Argentinean Children of Two Ethnicities.

OBJECTIVE: to explore changes in lipid levels in two groups of children of different ethnicities who were able to access vitamin D supplementation versus those who were not. METHODS: A prospective one-year study evaluated 87 San Antonio de los Cobres (SAC) Indigenous and 36 Buenos Aires (BA) urban schoolchildren aged 9.7 + 2.1 years between October 2013 and October 2014. SAC children included 70 (80.5%) treated with 100,000 IU/year of vitamin D and 17 (19.5%) untreated; and BA children included 25 (69,5%) treated and 11(30.5%) untreated. BMI, lipids, and 25-hydroxyvitamin D (25(OH)D) concentrations were measured at baseline and after one year. RESULTS: There was a significantly lower prevalence of overweight/obesity in SAC (n = 7; 8%) versus BA (n = 7; 36.4%) children. There was a significant association between changes in (25(OH)D) and changes in HDL-C levels in SAC (r0.44;p < 0.01) and in BA (r0.34;p < 0.05). Multiple linear regression analyses showed that changes in (25(OH)D ) were significantly associated with changes in HDL-C in SAC (Beta = 0.55, p = 0.02; R20.11) and BA children (Beta = 0.42, p = 0.04; R2 0.21) adjusted for age, gender, and BMI. Furthermore, multiple logistic regression analysis showed that children in the treated group had a likelihood six times greater of having HDL-C >40 mg/dL than the untreated group, adjusted for age, gender, and BMI (OR 6.3: CI 2.0 - 19.8; p < 0.01). CONCLUSION: These results suggest that children who had received vitamin D supplementation had significantly higher vitamin D status and HDL-C, as compared with non-supplemented children in both communities.

Waist Circumference Percentiles in Indigenous Argentinean School Children Living at High Altitudes.

BACKGROUND: Central obesity is associated with increased risk of type 2 diabetes. OBJECTIVES: The study objectives were to develop waist circumference (WC) percentiles, to determine if WC is associated with metabolic risk, and to compare our WC percentiles with those reported in the 2007-2010 National Health and Nutrition Examination Survey (NHANES). METHODS: A cross-sectional study of 1232 children (606 boys ) 5-14 years was performed from 2011 to 2014 in indigenous Koya children from northwestern Argentina. Anthropometric characteristics, glucose, lipids, and insulin levels were measured. Sex-specific reference percentiles were computed using the Lambda-Mu-Sigma (LMS) method. We obtained 2007-2010 NHANES data for comparison with our results. RESULTS: Compared with the NHANES 90th percentile, WC values for children in this study were lower by an average of 11.05 cm for girls and 12.66 cm for boys. The prevalence of low high-density lipoprotein cholesterol (HDL-C) was 11.8% in children with WC ≤50th percentile, 10.3% in children with WC >50th-70th percentile, 17.5% in children with WC >70th-90th percentile, and 21.3% in children with WC >90th percentile. The prevalence of high triglycerides (TG) was 19.5% in children with WC ≤50th percentile, 19.9% in children with WC >50th-70th percentile, 28.8% in children with WC >70th-90th percentile, and 39.7% in children with WC >90th percentile. Multiple logistic regression analyses showed that high TG values (>150 mg/dL) were significantly associated with WC [odds ratio (OR)] 1.05; 95% confidence interval (CI) 1.03-1.08; and low HDL-C values (<35 mg/dL) were significantly associated with WC (OR 1.04; 95% CI 1.01-1.06), adjusted for age and gender. CONCLUSION: We present for the first time WC reference data for indigenous Koya children ages 5-14 years. There was a significant association between WC and dyslipidemia in this community. Compared with the NHANES WC percentiles, our WC values were lower. These differences possibly reflect ethnicity or the lower prevalence of obesity.

Status of Dyslipidemia in Vitamin D Supplemented Argentinean Indigenous Children Versus A Non-supplemented Mixed Population Group.

BACKGROUND: Epidemiological studies have suggested an inverse association between circulating levels of vitamin D and cardiovascular disease risk biomarkers, including an atherogenic lipid profile. OBJECTIVE: To compare the prevalence and the distribution of lipid levels among vitamin D supplemented Argentinean indigenous San Antonio de los Cobres (SAC) children with a nonsupplemented Buenos Aires (BA) mixed population group. METHODS: A group of indigenous children from SAC with hypovitaminosis D supplemented with vitamin D; and a nonsupplemented group from a BA mixed population were compared via a cross sectional study. Anthropometric measures, glucose, lipids, vitamin D, and insulin were measured. RESULTS: The mean ages were 10.3 + 2.3 in SAC and 8.7 ± 1.8 years in BA children. There was a lower prevalence of overweight 7.9%(15/192) vs 17.8% (23/129); and of obesity 1.6% (3/192) vs 30.2% (39/129) in SAC vs. BA respectively. Approximately half of the SAC children versus 30% from BA had optimal vitamin D levels (≥30ng/mL). There was a significantly higher prevalence of high triglycerides (TG) (27.6%vs 4.6%) and low HDL-C (21.3% vs 5.4%) in SAC vs BA children, respectively. In separate linear regression models, we found that despite effective vitamin D repletion, SAC children had higher TG and TG/HDL-C values, whereas HDL-C levels were lower than those of BA children adjusted for age, gender, BMI, and insulin levels. CONCLUSION: Indigenous Argentinean children have a higher risk for dyslipidemia in comparison with BA children, even after vitamin D treatment, suggesting that dyslipidemia could be related to diet or ethnic backgrounds.

Improvement of Apolipoprotein B in Argentine Indigenous School Children after Vitamin D Supplementation.

OBJECTIVE: To determine whether vitamin D supplementation improves non-traditional cardiovascular risk factors such as Apo B levels among indigenous children. METHODS: A prospective two-year study evaluated a treated cohort of 190 children (104 males) aged 9.4+ 2.2 years. Children were divided into group A (n=104; 54.7%) and group B (n=86; 45.3%). Both groups received vitamin D supplementation with 100,000 u/year; group B was treated in 2013 and group A in 2014. All subjects were evaluated at the end of each treatment and anthropometric measures, lipids and vitamin D levels between the two groups were compared. RESULTS: Changes in vitamin D levels were significantly higher in Group A, which was supplied in 2014, than in group B, which was not supplied in 2014 (6.8 vs 0.96 ng/dL; respectively). Levels of LDL-C and Apo B were improved in group A versus B: LDL-C (-5.7 vs 6.9 mg/dL respectively) and Apo B (-0.9 vs 11. mg/dL respectively). Several multiple regression linear analyses showed that changes in vitamin D were significantly associated with lower LDL-C levels (Beta- 0.41, p<0.01; R2 0.07); and with lower Apo B levels (Beta-0.37, p<0.01; R2 0.17). CONCLUSION: Vitamin D supplementation among indigenous children could improve Apo B levels.

Tuning supramolecular G-quadruplexes with mono- and divalent cations.

Supramolecular G-quadruplexes (SGQs) are formed via the cation promoted self-assembly of guanine derivatives into stacks of planar hydrogen-bonded tetramers. Here, we present results on the formation of SGQs made from the 8-(m-acetylphenyl)-2'-deoxyguanosine (mAGi) derivative in the presence of various mono- and divalent cations. NMR and HR ESI-MS data indicate that varying the cation can efficiently tune the molecularity, the fidelity and stability (thermal and kinetic) of the resulting SGQs. The results show that, parallel to the previously reported potassium-templated hexadecamer (mAGi16·3K+), Na+, Rb+ and [Formula: see text] also promote the formation of similar supramolecules with high fidelity and molecularity. In contrast, the divalent cations Pb2+, Sr2+ and Ba2+ template the formation of octamers (mAGi8), with the latter two inducing higher thermal stabilities. Molecular dynamics simulations for the hexadecamers containing monovalent cations enabled critical insights that help explain the experimental observations.

Frequency and antibiotic susceptibility patterns of urinary pathogens in male outpatients in Argentina.

INTRODUCTION: Knowledge of the etiology and antimicrobial susceptibility patterns of uropathogens is important for determining the best treatment option. This study aimed to determine the distribution and antibiotic susceptibility patterns of bacterial strains isolated from adult male outpatients. METHODOLOGY: Between November 2012 and April 2013, 3,105 community urine samples were analyzed from adult male patients who attended the Laboratorio Hidalgo, Buenos Aires, Argentina. Antimicrobial susceptibility testing was performed by the Kirby-Bauer disc diffusion method. Isolates resistant to third generation cephalosporin were tested for extended-spectrum beta-lactamase (ESBL) production using the double-disk synergy test. RESULTS: Of the 3,105 urine samples analyzed, 791 (25.5%) had significant bacteriuria. The frequency of positive urine cultures increased significantly with patient age. Escherichia coli was isolated most frequently (47.3%), followed by Enterococcus faecalis (13.6%), and Klebsiella pneumoniae (11.9%). Gram-negative organisms represented 78.8% of urinary pathogens. The highest activities against Gram-negative bacteria were found with imipenem (99.0%), amikacin (98.1%), ertapenem (94.2%), fosfomycin (90.7%), and piperacillin-tazobactam (90.1%). The frequencies of ESBLs among E. coli, K. pneumoniae, and P. mirabilis were 15.2 %, 22.3%, and 8%, respectively. Fosfomycin, piperacillin-tazobactam, and nitrofurantoin were most effective against Gram-positive organisms. CONCLUSIONS: Fosfomycin may be an excellent option for cystitis treatment in patients without risk factors, whereas piperacillin-tazobactam is preferred for the treatment of parenchymatous UTIs, complicated UTIs, and UTIs associated with risk factors. To ensure the optimal selection of antibiotics, physicians should have access to up-to-date information about the local prevalence of antimicrobial resistance.