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RATIONALE: Experimental studies and epidemiological data in adults suggest that somatomedin-C (insulin-like growth factor-1, IGF-1) may play a role in asthma by modulating airway inflammation, bronchial hyperreactivity, and airway smooth muscle hyperplasia. However, its role in children with asthma is not well understood. METHODS: We established a birth cohort with 339 Chilean pregnant mothers enrolled at the time of delivery from December 2014 to January 2016. We obtained cord blood at birth and followed the offspring every 6 months until 30 months of age, recording data on atopy, wheezing, and other respiratory illnesses. We measured IGF-1 in cord blood and determined the Asthma Predictive Index (API) at 30 months. The cohort was divided according to the API. RESULTS: Complete data were available for 307/339 (91%) dyads, including 44 preschoolers with API+ and 263 with API-. Demographic characteristics were similar between groups, but mothers of API+ children had a higher prevalence of obesity, previous use of oral contraceptives, and higher education than those of API- children. API+ children had higher birth weight and significantly higher IGF-1 in cord blood (37.4 ± 13.2 in API+ vs. 30.5 ± 13.0 ng/ml in API-, p = .01). In the multivariable analysis, IGF-1 in cord blood remained independently associated with a higher risk of asthma (adjusted OR for API+ per ng/ml higher IGF-1 = 1.03 [1.0-1.06], p = .015). CONCLUSIONS: Higher insulin-like growth factor-1 in cord blood is associated with asthma risk in the preschool years.

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BACKGROUND: Observational studies suggest that asthma/wheezing improves after adenotonsillectomy (AT). However, there is a paucity of randomized clinical trial (RCT) specifically studying the effects of AT in asthma/wheezing. Therefore, we conducted a post-hoc analysis of the Childhood Adenotonsillectomy Trial (CHAT), the largest RCT of AT in children with obstructive sleep apnea (OSA) to test the hypothesis that AT would result in fewer wheezing episodes. METHODS: In the CHAT study, 464 children with OSA, aged 5-9 years, were randomized to early AT (n = 226) or watchful waiting with supportive care (WWSC) (n = 227). For this post-hoc analysis, children were categorized as having "any wheezing" versus "no wheezing" at baseline and at 7 months of follow-up. A multivariate analysis was conducted to evaluate the association between "any wheezing" at follow-up and treatment group after controlling for several potential confounders. RESULTS: Children in the "any wheezing" group were predominantly black, had more allergic rhinitis, eczema, second-hand smoke exposure, body mass index, apnea-hypopnea index (AHI), and had lower maternal education and family income than those in the "no wheezing group." In the AT arm, the prevalence of wheezing significantly decreased from baseline to follow-up (at 7 months of the intervention) (47% vs. 21.6%, p < 0.001); while in the WWSC arms did not change (45.2% vs. 43.1%, p = 0.67). In the multivariate analysis, second-hand smoke exposure, wheezing at baseline, and belong to WWSC arm (odds ratio: 3.65 [2.16-6.19]) increase the risk of wheezing at follow-up. CONCLUSION: This study demonstrated that AT decreased the risk of wheezing at 7 months of follow-up.

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Introduction: Self-efficacy has been related to different health preventive behaviors, included adherence to the Papanicolaou test-also called Pap smear or Pap test. The aim of this study is to test construct and criterion validity and reliability of a questionnaire on self-efficacy and the Pap test in Chilean women. Method: This study was carried out on a sample of 969 women of ages from 25 to 64, who are users of the public health care system in Santiago, Chile. The validity of the Self-Efficacy Scale for the Pap Smear Screening Participation (SES-PSSP) questionnaire was done by confirmatory factor analysis, external criteria by t-test, and reliability by Cronbach's alpha. Results: Three models were tested, obtaining a questionnaire with 20 items and 2 dimensions. The criteria validity was confirmed by adherence to the Pap test. The final questionnaire has a reliability of 0.95, measured by Cronbach´s alpha. Conclusion: A valid and reliable questionnaire to measure self-efficacy in relation to the Pap test is a relevant contribution in cervical cancer prevention, especially related to interventions focused on increasing adherence.

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Lower respiratory tract infections (LRTIs) produced by viruses are the most frequent cause of morbidity and mortality in children younger than 5 years of age. The immune response triggered by viral infection can induce a strong inflammation in the airways and cytokines could be considered as biomarkers for disease severity as these molecules modulate the inflammatory response that defines the outcome of patients. Aiming to predict the severity of disease during respiratory tract infections, we conducted a 1-year follow-up observational study in infants who presented upper or lower respiratory tract infections caused by seasonal respiratory viruses. At the time of enrollment, nasopharyngeal swabs (NPS) were obtained from infants to measure mRNA expression and protein levels of IL-3, IL-8, IL-33, and thymic stromal lymphopoietin. While all cytokines significantly increased their protein levels in infants with upper and lower respiratory tract infections as compared to control infants, IL-33 and IL-8 showed a significant increase in respiratory syncytial virus (RSV)-infected patients with LRTI as compared to patients with upper respiratory tract infection. We also found higher viral loads of RSV-positive samples with a greater IL-8 response at the beginning of the symptoms. Data obtained in this study suggest that both IL-8 and IL-33 could be used as biomarkers for clinical severity for infants suffering from LRTIs caused by the RSV.

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Mixture cure rate models have been developed to analyze failure time data where a proportion never fails. For such data, standard survival models are usually not appropriate because they do not account for the possibility of non-failure. In this context, mixture cure rate models assume that the studied population is a mixture of susceptible subjects who may experience the event of interest and non-susceptible subjects that will never experience it. More specifically, mixture cure rate models are a class of survival time models in which the probability of an eventual failure is less than one and both the probability of eventual failure and the timing of failure depend (separately) on certain individual characteristics. In this paper, we propose a Bayesian approach to estimate parametric mixture cure rate models with covariates. The probability of eventual failure is estimated using a binary regression model, and the timing of failure is determined using a Weibull distribution. Inference for these models is attained using Markov Chain Monte Carlo methods under the proposed Bayesian framework. Finally, we illustrate the method using data on the return-to-prison time for a sample of prison releases of men convicted of sexual crimes against women in England and Wales and we use mixture cure rate models to investigate the risk factors for long-term and short-term survival of recidivism.

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Diagnosing asthma in preschool children remains an unsolved challenge, at a time when early identification would allow for better education and treatment to prevent morbidity and lung function deterioration. OBJECTIVE: To evaluate if the asthma predictive index (API) can be used as surrogate for asthma diagnosis in preschoolers. METHODS: Birth cohort of 339 pregnant women enrolled at delivery and their offspring, who were followed for atopy, wheezing, and other respiratory illnesses through 30 months of age. The API was determined at 30 months of age by the researchers; and examined its association with physician-diagnosed asthma during the first 30 months, made independently by the primary care physician not involved in the study. RESULTS: Among 307 offspring with complete follow-up, 44 (14.3%) were API+. Maternal body mass index, maternal education, past oral contraceptive use, birthweight, placenta weight, age of daycare at 12 m, gastroesophageal reflux disease at 12 m, acute otitis media at 18 m, bronchiolitis, croup and pneumonia, cord blood adiponectin were all associated with API+. In the multivariable analysis, API+ was associated with almost sixfold odds of asthma diagnosis (adjusted OR = 5.7, 95% CI [2.6-12.3]), after adjusting for the relevant covariates above including respiratory infections like bronchiolitis and pneumonia. The API sensitivity was 48%, specificity 92%, 61% PPV, 88% NPV, 6.4 LR+, 0.56 LR-, 0.84 diagnosis accuracy. The adjusted odds for asthma was 11.4. CONCLUSIONS: This longitudinal birth cohort suggests, for first time, that API (a structured definition for asthma), could be used as a diagnostic tool, not only as a prognostic tool, in toddlers and preschoolers.

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INTRODUCTION: Several population studies have addressed oral health inequalities. Edentulism, functional dentition, and number of remaining teeth have been associated with different socioeconomic level measurements. The aim of this study was to evaluate the association between educational level and tooth loss in the Chilean population aged 15 years and above, based on the 2016-2017 National Health Survey (ENS 2016-2017). Material and Methods. The sample for this cross-sectional study comprised 5473 subjects. The main independent variable was educational level (LEL: low, MEL: medium, and HEL: high). To measure tooth loss, we considered the variables number of remaining teeth, edentulism, and functional dentition. We used logistic regressions to assess the condition of dentition according to the subject's EL. As to the number of teeth variable, linear regressions were conducted. The analyses were carried out considering the complex sampling design in SPSS 24.0. RESULTS: When comparing LEL subjects with HEL subjects, the adjusted difference in number of remaining teeth was 3.11 for the maxilla and 1.72 for the mandible. An individual with LEL had a 7.51 [3.50-16.10] and 6.06 [2.68-13.68] times higher risk of upper edentulism and lower edentulism than a HEL individual, respectively. Regarding functional dentition, the adjusted OR in HEL subjects was 13.33 [8.02-22.15] and in MEL subjects was 2.81 [2.03-3.87], compared to LEL results. CONCLUSIONS: LEL was associated with a significant tooth loss in the Chilean population. Subjects with LEL obtained a lower mean of number of remaining teeth and higher prevalence of edentulism and nonfunctional dentition.

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Background: Smoking is one of the main causes of death among adults worldwide. Aim: To characterize smoking among Chilean older people, according to sociodemographic and clinical variables. Material and Methods: Secondary analysis of data obtained during the National Health Survey 2009-10, selecting individuals aged 60 years and older. Expansion factors were used due to the complex design of the sample. Prevalence and characteristics of smoking were calculated, according to age, sex, educational level, marital status, healthcare insurance system and comorbidities. Results: Nineteen percent of older people were actual smokers, and 85% of these smokers were aged between 60 and 69 years. Forty-five percent were highly dependent to nicotine and 73% reported their intention to quit smoking. Conclusions: There is a high prevalence of tobacco smoking among Chilean older people. Prevention measures are needed.

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INTRODUCTION: The pleiotropic kininogen-kallikrein-kinin system is upregulated in pregnancy and localizes in the uteroplacental unit. To identify the systemic and local participation of the bradykinin type 2 receptor (B2R), this was antagonized by Bradyzide (BDZ) during 2 periods: from days 20 to 34 and from days 20 to 60 in pregnant guinea pigs. METHODS: Pregnant guinea pigs received subcutaneous infusions of saline or BDZ from gestational day 20 until sacrifice on day 34 (Short B2R Antagonism [SH-B2RA]) or on day 60 (Prolonged B2R Antagonism [PR-B2RA]). In SH-BDZA, systolic blood pressure was determined on day 34, while in PR-BDZA it was measured preconceptionally, at days 40 and 60. On gestational day 60, plasma creatinine, uricemia, proteinuria, fetal, placental and maternal kidney weight, and the extent of trophoblast invasion were evaluated. RESULTS: The SH-B2RA increased systolic blood pressure on day 34 and reduced trophoblast myometrial invasion, spiral artery remodeling, and placental sufficiency. The PR-B2RA suppressed the normal blood pressure fall observed on days 40 and 60; vascular transformation, placental efficiency, urinary protein, serum creatinine, and uric acid did not differ between the groups. The proportion of all studied mothers with lost fetuses was greater under BDZ infusion than in controls. CONCLUSION: The increased systolic blood pressure and transient reduction in trophoblast invasion and fetal/placental weight in the SH-B2R blockade and the isolated impact on blood pressure in the PR-B2R blockade indicate that bradykinin independently modulates systemic hemodynamics and the uteroplacental unit through cognate vascular and local B2R receptors.

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