Trypanosoma cruzi Secreted Cyclophilin TcCyP19 as an Early Marker for Trypanocidal Treatment Efficiency.

Cyclophilins (CyPs) are a family of enzymes involved in protein folding. Trypanosoma cruzi, the causative agent of Chagas disease, has a 19-kDa cyclophilin, TcCyP19, that was found to be secreted in parasite stages of the CL Brener clone and recognized by sera from T. cruzi-infected mice and patients. The levels of specific antibodies against TcCyP19 in T. cruzi-infected mice and subjects before and after drug treatment were measured by an in-house enzyme linked immunosorbent assay (ELISA). Mice in the acute and chronic phase of infection, with successful trypanocidal treatments, showed significantly lower anti-TcCyP19 antibody levels than untreated mice. In children and adults chronically infected with T. cruzi, a significant decrease in the anti-TcCyP19 titers was observed after 12 months of etiological treatment. This decrease was maintained in adult chronic patients followed-up 30-38 months post-treatment. These results encourage further studies on TcCyP19 as an early biomarker of trypanocidal treatment efficiency.

Neutralization of alpha, gamma, and D614G SARS-CoV-2 variants by CoronaVac vaccine-induced antibodies.

Vaccination generates a neutralizing immune response against SARS-CoV-2. The genomic surveillance is showing the emergence of variants with mutations in spike, the main target of neutralizing antibodies. To understand the impact of these variants, we report the neutralization potency against alpha, gamma, and D614G SARS-CoV-2 variants in 44 individuals that received two doses of CoronaVac vaccine, an inactivated SARS-CoV-2 vaccine. Plasma samples collected at 60 days after the second dose of CoronaVac were analyzed by the reduction of cytopathic effect in Vero E6 cells with the three infectious variants of SARS-CoV-2. Plasma showed lower neutralization with alpha (geometric mean titer [GMT] = 18.5) and gamma (GMT = 10.0) variants than with D614G (GMT = 75.1) variant. Efficient neutralization against the alpha and gamma variants was not detected in 31.8% and 59.1% of plasma, respectively. These findings suggest the alpha and gamma variants could escape from neutralization by antibodies elicited by vaccination. Robust genomic and biological surveillance of viral variants could help to develop effective strategies for the control of SARS-CoV-2.

Circulating Cytokine and Chemokine Profiles of Trypanosoma cruzi-Infected Women During Pregnancy and Its Association With Congenital Transmission.

BACKGROUND: Trypanosoma cruzi, the causative agent of Chagas disease, can be transmitted to the offspring of infected women, which constitutes an epidemiologically significant parasite transmission route in nonendemic areas. It is relevant to evaluate differentially expressed factors in T. cruzi-infected pregnant women as potential markers of Chagas congenital transmission. METHODS: Circulating levels of 12 cytokines and chemokines were measured by enzyme-linked immunosorbent assay or cytometric bead array in T. cruzi-infected and uninfected pregnant women in their second trimester of pregnancy and control groups of T. cruzi-infected and uninfected nonpregnant women. RESULTS: Trypanosoma cruzi-infected women showed a proinflammatory Th1-biased profile, with increased levels of tumor necrosis factor (TNF)-α, interleukin (IL)-12p70, IL-15, and monokine induced by interferon-gamma (MIG). Uninfected pregnant women presented a biased response towards Th2/Th17/Treg profiles, with increased plasma levels of IL-5, IL-6, IL-1ß, IL-17A, and IL-10. Finally, we identified that high parasitemia together with low levels of TNF-α, IL-15, and IL-17, low TNF-α/IL-10 ratio, and high IL-12p70 levels are factors associated with an increased probability of Chagas congenital transmission. CONCLUSIONS: Trypanosoma cruzi-infected pregnant women who did not transmit the infection to their babies exhibited a distinct proinflammatory cytokine profile that might serve as a potential predictive marker of congenital transmission.

Quantitative detection of SARS-CoV-2 RNA in nasopharyngeal samples from infected patients with mild disease.

Diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) cases is based on the count of real-time reverse transcription-plymerase chain reaction (RT-PCR) positive people. Viral load by real-time RT-PCR has been suggested as a biomarker of the SARS-CoV-2 infection. However, the association of viral load and severity of the disease is not yet resolved. Nasopharyngeal samples from 458 patients were tested by RT-PCR for SARS-CoV-2 diagnosis. Relative quantitation was made by the comparative threshold cycle (ΔΔCt ) formula between ORF1ab viral and RNase P housekeeping genes. Absolute viral load was calculate using a reference positive control. Most prevalent clinical signs were cough (75.8%), myalgia (66.7%), and fever (48.5%). Hypertension (18.2%), neurological diseases (15.1%), and asthma and hypothyroidism (12.1%) were most frequent comorbidities. Fever, either as an exclusive symptom or combined with others, was associated with high viral loads ( 2-∆∆Ct range, 35.65-155.16; 4.25-4.89 log10 RNA copies/test]). During the first week after onset of symptoms in mild patients up to 60 years-old was detected the peak of viral load. Children under 10 years old have a high viral load (313.84; 2.50) in the first 2 days postinfection with a sharp decline thereafter. Cases between 10 and 49 years old mostly showed low and moderate viral load during the first 2 days postinfection (range, 0.03 to 17.24; -1.50 to 1.24). Patients over 60 years old have high viral load up to the second week after the onset of symptoms (range, 25.32-155.42; 1.40-2.19), indicating the longer presence of the virus in them. These findings suggest the viral load in nasopharyngeal swabs would help to monitor the SARS-CoV-2 infection in mild coronavirus disease 2019 cases.

Trypanosoma cruzi infection in Cyclophilin D deficient mice.

Trypanosoma cruzi is the causative agent of Chagas disease, which is endemic in Latin America and around the world through mother to child transmission. The heart is the organ most frequently affected in the chronic stage of the human infection and depends on mitochondria for the required energy for its activity. Cyclophilins are involved in protein folding and the mitochondrial isoform, Cyclophilin D (CyPD), has a crucial role in the opening of the mitochondrial permeability transition pore. In the present study, we infected CyPD deficient mice, with ablation of the Ppif gene, with T. cruzi parasites and the course of the infection was analyzed. Parasite load, quantified by PCR, was significantly lower in skeletal and cardiac tissues of Ppif-/- mice compared to wild type mice. In vitro cultured cardiomyocytes and macrophages from mice lacking CyPD exhibited lower percentage of infected cells and number of intracellular parasites than those observed for wild type mice. Although histopathological analysis of heart and mRNA of heart cytokines showed differences between T. cruzi-infected mice compared to the uninfected animals, no significant differences were found mice due to the ablation of the Ppif gene. Our results suggest that cells deficient for mitochondrial CyPD, inhibited for the mitochondrial membrane potential collapse, reduces the severity of parasite aggression and spread of cellular infection.

Phylogenetic analysis of the first four SARS-CoV-2 cases in Chile.

The current pandemic caused by the new coronavirus is a worldwide public health concern. To aboard this emergency, and like never before, scientific groups around the world have been working in a fast and coordinated way to get the maximum of information about this virus when it has been almost 3 months since the first cases were detected in Wuhan province in China. The complete genome sequences of around 450 isolates are available, and studies about similarities and differences among them and with the close related viruses that caused similar epidemics in this century. In this work, we studied the complete genome of the first four cases of the new coronavirus disease in Chile, from patients who traveled to Europe and Southeast Asia. Our findings reveal at least two different viral variants entries to Chilean territory, coming from Europe and Asia. We also sub-classified the isolates into variants according to punctual mutations in the genome. Our work contributes to global information about transmission dynamics and the importance to take control measures to stop the spread of the infection.

Heterogeneity in influenza seasonality and vaccine effectiveness in Australia, Chile, New Zealand and South Africa: early estimates of the 2019 influenza season.

We compared 2019 influenza seasonality and vaccine effectiveness (VE) in four southern hemisphere countries: Australia, Chile, New Zealand and South Africa. Influenza seasons differed in timing, duration, intensity and predominant circulating viruses. VE estimates were also heterogeneous, with all-ages point estimates ranging from 7-70% (I2: 33%) for A(H1N1)pdm09, 4-57% (I2: 49%) for A(H3N2) and 29-66% (I2: 0%) for B. Caution should be applied when attempting to use southern hemisphere data to predict the northern hemisphere influenza season.

Implementation of a Computerized Decision Support System for Computed Tomography Scan Requests for Nontraumatic Headache in the Emergency Department.

BACKGROUND: Nontraumatic headache is a frequent complaint in the emergency department (ED). Cranial computed tomography (CT) is a widely available test for the diagnostic work-up, despite the risk of exposure to ionizing radiation. OBJECTIVES: We sought to develop and evaluate a cranial CT request computerized decision support system (CDSS) for adults with their first presentation of unusual severe nontraumatic headache in the ED. METHODS: Electronic database searches identified clinical decision and prediction rules and studies delineating risk factors in nontraumatic headache. A long list of risk factors extracted from these articles was reduced by a 30-member multidisciplinary expert panel (radiologists, emergency physicians, methodologists), using a 90% agreement threshold. This shortlist was used to develop the algorithm for the cranial CT request CDSS, which was implemented in March 2016. Impact evaluation compared CT scan frequency and diagnostic yield of pathologic findings before (March-August 2015) and after (March-August 2016) implementation. RESULTS: From the 10 selected studies, 10 risk factors were shortlisted to activate a request for cranial CT. Before implementation, 377 cranial CTs were ordered (15.3% of 2469 CT scans) compared with 244 after (9.5% of 2561 CT scans; pre-post difference 5.74%; 95% confidence interval [CI] 3.92-7.56%; p < 0.001), corresponding to a 37.6% relative reduction in the test ordering rate (95% CI 25.7-49.5%; p < 0.001). Despite the reduction in cranial CT scans, we did not observe an increase in pathological findings after introducing the decision support system (70 cases before [18.5%] vs. 35 cases after [14.3%]; pre-post difference -4.0% [95% CI -10.0 to 1.6%]; p = 0.170). CONCLUSION: In nontraumatic headache among adults seen in the ED, CDSS decreased the cranial CT request rate but the diagnostic yield did not improve.

Serum Cytokines as Biomarkers of Early Trypanosoma cruzi infection by Congenital Exposure.

Trypanosoma cruzi, the causing agent of Chagas disease, leads to an activation of the immune system in congenitally infected infants. In this study, we measured a set of cytokines/chemokines and the levels of parasitemia by quantitative PCR in the circulation of neonates born to T. cruzi-infected mothers to evaluate the predictive value of these mediators as biomarkers of congenital transmission. We conducted a retrospective cohort study of 35 infants with congenital T. cruzi infection, of which 15 and 10 infants had been diagnosed by detection of parasites by microscopy in the first and sixth month after delivery, respectively, and the remaining 10 had been diagnosed by the presence of T. cruzi-specific Abs at 10-12 mo old. Uninfected infants born to either T. cruzi-infected or uninfected mothers were also evaluated as controls. The plasma levels of IL-17A, MCP-1, and monokine induced by IFN-γ were increased in infants congenitally infected with T. cruzi, even before they developed detectable parasitemia or seroconversion. Infants diagnosed between 6 and 12 mo old also showed increased levels of IL-6 and IL-17F at 1 mo of age. Conversely, infants who did not develop congenital T. cruzi infection had higher levels of IFN-γ than infected infants born to uninfected mothers. Monokine induced by IFN-γ, MCP-1, and IFN-γ production induced in T. cruzi-infected infants correlated with parasitemia, whereas the plasma levels of IL-17A, IL-17F, and IL-6 were less parasite load dependent. These findings support the existence of a distinct profile of cytokines and chemokines in the circulation of infants born to T. cruzi-infected mothers, which might predict congenital infection.

Changes in socio-economic level and their impact on nutritional status: a follow-up study among young Chilean adults.

OBJECTIVE: To verify the association between changes in socio-economic level (SEL) and nutritional status of Chilean adults over a 10-year period. DESIGN: Concurrent cohort study.Setting/SubjectsIndividuals born from 1974 to 1978 in the Valparaíso Region of Chile were evaluated between 2000 and 2002 (n 1232) and again between 2010 and 2012 (n 796). SEL was characterized according to the occupation and educational level of the head of household. Nutritional status was based on measurement of BMI and waist circumference (WC). RESULTS: Between the first and second evaluation there was a 13 % reduction in the number of individuals classified as poor and a 12 % increase in those classified in the medium high SEL. Increases in BMI were found among women who remained in the low SEL (ß=2·2, 95 % CI 0·16, 2·87) compared with women who maintained the same SEL (and whose SEL was above low over the 10-year period). Women who remained in the low SEL increased their WC (ß=4·10, 95 % CI 0·27, 7·93). There were no associations between nutritional status and SEL among males. CONCLUSIONS: In the period studied, the SEL of the study population improved between the third and fourth decade of life, but BMI and WC also increased among women, with the lowest socio-economic group experiencing the greatest changes. Meanwhile, among males we found no association between anthropometric measurements and changes in SEL.

[Pattern of smoking and socioeconomic status in two cohorts of young adults]. / Patrón de tabaquismo y nivel socioeconómico en dos cohortes de adultos jóvenes.

BACKGROUND: One in five deaths that occur in Chile can be attributed to smoking whose prevalence remains high, despite interventions aimed at reducing it. AIM: To compare the prevalence of smoking and its intensity among young adults born 15 years apart and determine their association with socioeconomic status (SES). MATERIAL AND METHODS: Two cohorts of young adults living in the Valparaiso Region of Chile were evaluated in the third decade of life. Cohort 1 was evaluated between 2000 and 2002 (n = 1232) and cohort 2 between 2014 and 2017 (n = 1078). RESULTS: In cohort 1, 57.5% (95% Confidence Interval (CI) 54.6-58.7) of the subjects reported smoking, with a median of 3 (Interquartile range (ICR:1-6) cigarettes/day. This percentage fell to 40.2% (CI: 37.5-43.1) with a similar median in cohort 2. Analyzing cohort 2, the odds ratio (OR) for smoking was 2.24 (CI 1.48-3.38) in the medium SES, compared with the medium high SES. The figures for low medium and low SES were 2.72 (CI: 1.85-3.99) and 3.01 (1.85-4.88). Similarly, in this cohort there was a significantly higher risk of being a heavy smoker in lower SES. No associations between smoking or its intensity and SES were observed in cohort 1. CONCLUSIONS: Smoking behavior has decreased among young adults evaluated at the same age in two generational cohorts in the third decade of life. In the most recent cohort analyzed, smoking and its intensity increase along with a decrease in SES.

Indigenous and tribal peoples' health (The Lancet-Lowitja Institute Global Collaboration): a population study.

BACKGROUND: International studies of the health of Indigenous and tribal peoples provide important public health insights. Reliable data are required for the development of policy and health services. Previous studies document poorer outcomes for Indigenous peoples compared with benchmark populations, but have been restricted in their coverage of countries or the range of health indicators. Our objective is to describe the health and social status of Indigenous and tribal peoples relative to benchmark populations from a sample of countries. METHODS: Collaborators with expertise in Indigenous health data systems were identified for each country. Data were obtained for population, life expectancy at birth, infant mortality, low and high birthweight, maternal mortality, nutritional status, educational attainment, and economic status. Data sources consisted of governmental data, data from non-governmental organisations such as UNICEF, and other research. Absolute and relative differences were calculated. FINDINGS: Our data (23 countries, 28 populations) provide evidence of poorer health and social outcomes for Indigenous peoples than for non-Indigenous populations. However, this is not uniformly the case, and the size of the rate difference varies. We document poorer outcomes for Indigenous populations for: life expectancy at birth for 16 of 18 populations with a difference greater than 1 year in 15 populations; infant mortality rate for 18 of 19 populations with a rate difference greater than one per 1000 livebirths in 16 populations; maternal mortality in ten populations; low birthweight with the rate difference greater than 2% in three populations; high birthweight with the rate difference greater than 2% in one population; child malnutrition for ten of 16 populations with a difference greater than 10% in five populations; child obesity for eight of 12 populations with a difference greater than 5% in four populations; adult obesity for seven of 13 populations with a difference greater than 10% in four populations; educational attainment for 26 of 27 populations with a difference greater than 1% in 24 populations; and economic status for 15 of 18 populations with a difference greater than 1% in 14 populations. INTERPRETATION: We systematically collated data across a broader sample of countries and indicators than done in previous studies. Taking into account the UN Sustainable Development Goals, we recommend that national governments develop targeted policy responses to Indigenous health, improving access to health services, and Indigenous data within national surveillance systems. FUNDING: The Lowitja Institute.

Genomic and physiological characterization of a laboratory-isolated Acinetobacter schindleri ACE strain that quickly and efficiently catabolizes acetate.

An Acinetobacter strain, designated ACE, was isolated in the laboratory. Phylogenetic tests and average nucleotide identity value comparisons suggested that ACE belongs to the species Acinetobacterschindleri. We report for the first time the complete genome sequence of an A. schindleri strain, which consists of a single circular chromosome of 3 001 209 bp with an overall DNA G+C content of 42.9 mol% and six plasmids that account for 266 844 bp of extrachromosomal material. The presence or absence of genes related to carbon catabolism and antibiotic resistance were in agreement with the phenotypic characterization of ACE. This strain grew faster and with a higher biomass yield on acetate than the reference strain Acinetobacter baylyi ADP1. However, ACE did not use aromatic compounds and was unable to grow on common carbon sources, such as glucose, xylose, glycerol or citrate. The gluconeogenic and the catechol pathways are complete in ACE, but compounds that are converted to protocatechuate did not sustain growth since some genes of this pathway are missing. Likewise, this strain could not grow on glucose because it lacks the genes of the Entner-Doudoroff pathway. Minimal inhibitory concentration data showed that ACE was susceptible to most of the antimicrobial agents recommended for the clinical treatment of Acinetobacter spp. Some genes related to a possible human-microbe interaction were found in the ACE genome. ACE is likely to have a low pathogenic risk, as is the case with other A. schindleri strains. These results provide a valuable reference for broadening the knowledge of the biology of Acinetobacter.

Change in postmenarche anthropometric indicators in indigenous and nonindigenous adolescents from Chile.

OBJECTIVE: To analyze the change in anthropometric indicators between menarche and 36 months after menarche among indigenous and non-indigenous adolescents from the Araucanía Region of Chile. METHOD: This was a concurrent cohort study. Of 8,504 girls interviewed, 114 indigenous adolescents and 123 nonindigenous adolescents who had recently experienced menarche were selected. Body mass index (BMI), BMI by age (BMI z-score), waist circumference (WC) and body fat percentage (BF%) were evaluated at menarche and 6, 12, 18, 24, 30, and 36 months postmenarche. Linear models estimated with generalized estimating equations were used to quantify disparities adjusted for baseline anthropometric values, age at menarche, place of residence, and socioeconomic level. RESULTS: Indigenous girls presented menarche 4 months later than nonindigenous girls and had significantly higher BMI (1.5 kg/m2 ), BMI z-score (0.4), WC (2.9 cm), and BF% (1.7%) at menarche. Adjusted results did not show an association between being indigenous and post-menarche anthropometric variables: BMI = 0.1 kg/m2 (CI = -0.3; 0.5), BMI z-score = 0 (CI = -0.1; 0.1), WC = 0.7 cm (CI = -0.6; 2.0), and BF% = 0.5% (CI = -0.2; 1.3). It is important to mention that the mean BMI z-score of both groups were in the overweight category. CONCLUSION: At menarche, indigenous girls had higher values than nonindigenous girls for all anthropometric variables, and this trend remained after menarche, with no further change in ethnic disparity over the subsequent three years. This reinforces the need to implement interventions to prevent or control excess weight prior to menarche, with emphasis on indigenous girls.

[Health inequality gap in inmigrant versus local children in Chile]. / Brechas de desigualdad en salud en niños migrantes versus locales en Chile.

INTRODUCTION: Children and young international migrants face different health challenges compa red with the local population, particularly if they live in insecure environments or adverse social conditions. This study seeks to identify gaps in health outcomes of children between immigrant and local population in Chile. METHODS: This study analyses data from three sources: (i) Born in Chile: Electronic records of antenatal visits from all municipal antenatal clinics of Recoleta in 2012; (ii) Growing up in Chile: Population survey "National Socioeconomic Characterization" (CASEN) from 2013 and (iii) Getting sick in Chile: Data of all hospital discharges in 2012, provided by the department of statistics and health information (DEIS) of the Ministry of Health. RESULTS: (I) Born in Chile: Im migrants more frequently have psychosocial risk (62.3% vs 50.1% in Chileans) and enter later into the program (63.1% vs 33.4% enter later than 14 weeks of pregnancy). All birth outcomes were better among immigrants (e.g. caesarean sections rates: 24.2% immigrants vs % Chileans). (ii) Growing up in Chile: A higher proportion of migrant children is outside the school system and lives in multidi mensional poverty (40% immigrants vs 23.2% Chileans). (iii) Getting sick in Chile: Injuries and other external causes were more frequent cause of hospitalisation among migrants (23.6%) than the local population (16.7%) aged between 7 and 14 years. CONCLUSIONS: Addressing the needs of the children in Chile, regardless of their immigration status, is an ethical, legal and moral imperative.

Changes in symptoms of asthma and rhinitis by sensitization status over ten years in a cohort of young Chilean adults.

BACKGROUND: We investigated the net changes in prevalence of symptoms of asthma and rhinitis over 10 years in a cohort of young by baseline sensitization status. METHODS: One thousand one hundred ninety three Chilean adults subjects aged 22-28 living in a semi-rural area of central Chile answered a lifestyle and the European Community Respiratory Health Survey (ECRHS) questionnaires. Bronchial hyper-responsiveness (BHR) and skin prick test (SPT) to eight allergens were measured at baseline in 2001. Ten years later, 772 participants completed the questionnaires again. Estimates of adjusted net changes in prevalence of symptoms by sensitization status at baseline and association between sensitization status at baseline and respiratory symptoms ten years later were assessed. RESULTS: A quarter of the participants were sensitized to at least one allergen in 2001. Prevalence of wheeze had a net change per year of -0.37 % (95 % Confidence Interval -0.71 to 0.02 %; p = 0.067). Self-reported nasal allergies in the last 12 months increased by 0.83 % per year (95 % CI 0.49 to 1.17 %; p < 0.001). Those sensitized to either cat fur (OR 1.76; CI 1.01 to 3.05), cockroach, (OR 2.09; 1.13 to 3.86) blend of grass and pollens (1.78; 95 % CI 1.08 to 2.92), or weeds (OR 1.77; 95 % CI 1.01 to 3.12) in 2001 were more likely to have wheeze in the last 12 months 10 years later. CONCLUSION: Symptoms of asthma remained stable or slightly changed over 10 years in adults, whilst rhinitis and nasal allergies greatly increased. Being sensitized to at least one allergen is a risk factor for persistent symptoms of asthma and rhinitis, but not for determining net changes of symptoms over time. The underlying causes for the contrasting trends between asthma and nasal allergy are unknown.

[Association of C reactive protein levels with metabolic syndrome in adults: a population-based study]. / Síndrome metabólico e inflamación en adultos: Un estudio poblacional.

BACKGROUND: Metabolic syndrome is highly prevalent among adults in Chile and represents a health risk. AIM: To determine the relationship between metabolic syndrome (MetS) and its components, with C reactive protein levels (CRP) as an inflammation marker. MATERIAL AND METHODS: The population studied consisted of 736 individuals born in a hospital from Valparaíso Region, aged between 32-38 years at the time of the study. MetS was identified according to the Adult Treatment Panel (ATP) III guidelines and inflammation was measured using ultra-sensitive CRP. This parameter was classified as normal for values from 0 to 3 mg/L, high for values from 3.01 to 10 mg/L and very high for values > 10 mg/L. RESULTS: Median CRP was in the normal range (1.9 mg/L, interquartile range 0.7-5.2) and was higher among women than men (2.2 and 1.4 mg/L respectively, p < 0.01). Twenty seven percent of participants had MetS. One-fourth had high blood glucose values, one-third had high triglyceride levels and 28% had blood pressure values over those established as normal in MetS. Elevated waist circumference (WC) and low HDL cholesterol were found among almost 50% of participants. A relationship between MetS and high CRP was only found among men with an Odds ratio (OR) of 2.04 (95% confidence intervals (CI): 1.11-3.73). The same association was observed for high triglyceride levels with an OR of 2.02 (CI: 1.17-3.49) and high WC with an OR of 3.89 (CI: 2.06-7.36). Among women, the only relationship observed was between abdominal obesity and very high CRP with an OR of 2. 65 (CI: 1.20-5.84). CONCLUSIONS: Metabolic syndrome, high triglyceride levels, and abdominal obesity were associated with inflammation only in men.

Oxidative stress damage in the protozoan parasite Trypanosoma cruzi is inhibited by Cyclosporin A.

Cyclosporin A (CsA) specifically inhibits the mitochondrial permeability transition pore (mPTP). Opening of the mPTP, which is triggered by high levels of matrix [Ca2+] and/or oxidative stress, leads to mitochondrial dysfunction and thus to cell death by either apoptosis or necrosis. In the present study, we analysed the response of Trypanosoma cruzi epimastigote parasites to oxidative stress with 5 mm H2O2, by studying several features related to programmed cell death and the effects of pre-incubation with 1 µ m of CsA. We evaluated TcPARP cleavage, DNA integrity, cytochrome c translocation, Annexin V/propidium iodide staining, reactive oxygen species production. CsA prevented parasite oxidative stress damage as it significantly inhibited DNA degradation, cytochrome c translocation to cytosol and TcPARP cleavage. The calcein-AM/CoCl2 assay, used as a selective indicator of mPTP opening in mammals, was also performed in T. cruzi parasites. H2O2 treatment decreased calcein fluorescence, but this decline was partially inhibited by pre-incubation with CsA. Our results encourage further studies to investigate if there is a mPTP-like pore and a mitochondrial cyclophilin involved in this protozoan parasite.

Postmenarche growth: cohort study among indigenous and non-indigenous Chilean adolescents.

BACKGROUND: In Chile, indigenous and non-indigenous schoolchildren have the same stature when they begin school but indigenous adults are shorter, indicating the importance of analyzing growth during puberty. The aim of this study was to compare the growth of indigenous and non-indigenous girls during the 36 months after menarche in Chile's Araucanía Region. METHODS: A concurrent cohort study was conducted to compare growth in the two ethnic groups, which were comprised of 114 indigenous and 126 non-indigenous girls who recently experienced menarche and were randomly selected. Height was measured at menarche and at 6, 12, 18, 24 and 36 months post-menarche. General linear models were used to analyze growth and a generalized estimating equation model was used to compare height at 36 months post-menarche. RESULTS: At menarche, the Z-score of height/age was less for indigenous than non-indigenous girls (-0.01 vs. -0.61, p < 0.001). Indigenous girls grew at a slower rate than non-indigenous girls (6.5 vs. 7.2 cm, p = 0.02), and height at 36-months post-menarche reached -0.82 vs. -0.35 cm (p <0.001). In an adjusted model at 36 months post-menarche, indigenous girls were 1.6 cm shorter than non-indigenous girls (95% confidence interval: -3.13 to -0.04). CONCLUSIONS: The height of indigenous girls at menarche was lower than that of non-indigenous girls and they subsequently grew less, maintaining the gap between the two groups. At the end of the follow-up period, the indigenous girls were shorter than their non-indigenous peers.

[Intake of sugar-sweetened non-alcoholic beverages and body mass index: A national sample of Chilean school children]. / Ingesta de bebidas azucaradas analcohólicas e índice de masa corporal en escolares chilenos.

OBJECTIVE: To estimate the association between the intake of sugar-sweetened non-alcoholic beverages and body mass index (BMI) in Chilean school children. MATERIALS AND METHODS: Food consumption frequency data were analyzed for school children aged 6 to 18. The association between consumption of sugar-sweetened beverages and BMI was estimated by multivariate lineal regression models. RESULTS: Sugar-sweetened beverages are consumed on a daily basis by 92% (95%CI:90-94) of subjects with daily intake medians of 424 mL (p25-p75:212-707). Every extra daily portion of sugar-sweetened beverages consumed by school children aged 6 to 13 is associated with 0.13 BMI z-scores (95%CI:0.04-0.2;p=0.01). CONCLUSIONS: School children consume sugar-sweetened beverages daily with intake medians close to 0.5L. There is an association between sugar-sweetened beverage consumption and higher BMI in Chilean school children.