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We investigated the production of ammonium via photodegradation of dissolved organic matter (DOM) in the coastal upwelling system off central Chile (36° S). Photoam-monification experiments were carried out using exudates obtained from representative diatom species (Chaetoceros muelleri and Thalassiosira minuscule) and natural marine DOM under simulated solar radiation conditions. Additionally, we evaluated the use of photoproduced ammonium by natural microbial communities and separated ammonium oxidizing archaea and bacteria by using GC-7 as an inhibitor of the archaeal community. We found photoammonification operating at two levels: via the transformation of DOM by UV radiation (abiotic ammonification) and via the simultaneous occurrence of abiotic phototransformation and biological remineralization of DOM into NH4+ (referred as gross photoproduction of NH4+). The maximum rates of abiotic ammonification reached 0.057 µmol L-1 h-1, whereas maximum rates of gross photopro- duction reached 0.746 µmol L-1 h-1. Our results also suggest that ammonium oxidizing archaea could dominate the biotic remineralization induced by photodegradation of organic matter and consequently play an important role in the local N cycle. Abiotic ammonium photoproduction in coastal upwelling systems could support between 7 and 50%of the spring-summer phytoplankton NH4+ demand. Surprisingly, gross ammonium photoproduction (remineralization induced by abiotic ammonification) might support 50 to 180% of spring-summer phytoplankton NH4+ assimilation. [ABSTRACT FROM AUTHOR]

The ‘Espinal’ agroforestry system of the Mediterranean zone of central Chile, which covers an area of 2000 000 ha, is in various stages of degradation due to human activities. The objective of our study was: (i) to determine the effects of the canopy cover of Acacia caven (‘Espino’) on total soil organic carbon (SOC), soil respiration and the labile components of soil organic matter (microbial biomass, and light fraction); and (ii) to determine the influence of ecosystem degradation on total and labile components of SOC. Soils of the study area are classified as fine, mixed, active, mesic Ultic Palexeralfs, typical of the Mediterranean-type environment. We investigated sites according to the percentage coverage of A. caven canopy: (i) well-preserved Espinal (WPE), 80–51% cover; (ii) good Espinal (GE), 50–26% cover; (iii) degraded Espinal (DE), 25–11% cover; and (iv) very degraded Espinal (VDE), < 10% cover. In addition, a site under native forest (NF) was included to characterize the original state of the zone. Soil samples were taken under and outside the canopy of A. caven at two depths, 0–5 and 5–10 cm. We conclude that the microbial biomass carbon (Cmic), and total and labile components of SOC are influenced by the presence of the A. caven tree, with greater values under than outside its canopy. Under the tree canopy, to a depth of 10 cm, Cmic was less under all the agroforestry systems than in NF (46 and 30% less for WPE and GE, respectively, and 67 and 57% less for DE and VDE). However, there was no clear trend for less Cmic with increased ecosystem degradation, especially outside the canopy. However, the respiration of microbial communities was affected by ecosystem degradation for both soil depths under the tree canopy, e.g. soil respiration in VDE ecosystems was about 50% greater than that found in WPE ecosystems. Increasing the coverage of the A. caven tree in the semiarid ecosystems of central Chile, e.g. changing from VDE to WPE, would result in an eventual, long-term (over several centuries) increase in soil organic C of approximately 50%. [ABSTRACT FROM AUTHOR]

Brucella abortus is an intracellular bacterium, causal agent of bovine brucellosis. Many vaccines have been development with the propose of prevent this illness that causes severe economic looses. In Chile is been used strain RB51, which is capable of provide immunity, but has some disadvantages like causing reaction in humans, induce abortion in pregnant cattle and has the probability to change to his virulent form. The immunization with DNA vaccines, present the advantage of stimulating both humoral and cellular response, being this last one essential to prevent brucellosis. Our aim is to test intraspleen injection with a DNA vaccine that codifies for Cu/Zn superoxide dismutase (Cu/Zn SOD) of Brucella abortus, and observe his effect over T cell populations. BALB/c mice are immunized by intraspleen pathway with a plasmid encoding for Cu/Zn SOD. As a negative control a group of mice were injected with the parental plasmid (pcDNA 3.1) and another with PBS. 2 or 4 weeks after immunization, mice were challenge with the pathogenic strain 2308 for a protection study. In another group, spleen were obtained to perform a lymphocytes proliferation assay and cytokine quantification, assay repeated to both CD4+ and CD8+ T cell populations, sorted by flow cytometry. Inoculation induces antigen-specific lymphocytes proliferation for both CD4+ and CD8+ T cells, and for total population of lymphocytes from the spleen 4 weeks after immunization, and also induces protection against challenge with the pathogenic strain of Brucella abortus 2308, 2 and 4 weeks after immunization. Financed by Fondecyt Grant 1010851, Chile. [ABSTRACT FROM AUTHOR]

Few centers worldwide perform pediatric lung transplantation. The use of Bilateral Lobar Transplant or Reduced lung (lobectomy or wedge) are still under debate. We present a single center experience in the only pediatric lung transplant center in Chile with lobar or reduced donate lungs in pediatric transplant. Retrospective analysis of pediatric lung transplant patients performed between 2006 and 2022. Compared analysis between Reduced/Lobar Group(RLG) vs whole Lung Group (WLG). Demographic data, procedura and post operative data were recorded and analyzed. Between 2006 and 2022 we performed DLTx in fifteen patients <15 years old(yo), among these 6 cases were RLG and 9 patients underwent WLG Main diagnosis (85%) was Cystic fibrosis (CF) in both groups. Average Age at surgery where 9 years (7-15) in RLG and 13 years (11 - 15) in WLG. Pre transplant average BMI was 16 (14-19) in RLG and 19 (16-21) in WLG. Intraoperative ECMO VA was used in 100% of RLG and 80% in WLG. Lung perfusion (EVLP) was used in 2 cases of RLG vs 0 of WLG. Surgical complications were unfrequent, bleeding 1/6 RLG and 1/9 WLG. Both groups were comparable with no statistically significant differences between them in a univariate analysis. The decision to perform size-reduced lung transplants was made mainly based on the donor-recipient (D/R) height mismatch known before, and finally adjusted in the operating room during implantation upon visual assessment of the size-discrepancy. Middle lobe resection and resection of the lingula were undertaken either on the back-table preparation or occasionally after implantation (2 patients). For lobar transplants, lobectomy separation was done during back-table preparation (4 patients). Difference in VEF1 at 1 , 6, 12, and 24 months have no statistical difference between both groups.The overall estimated survival by Kaplan-Meier was 107 months (95% CI 78-137), and for the lobar group (n 5) is 120 months (95% CI 67 -172) , with no statistically significant difference between both groups In this small cohort of Pediatric lung transplant we found no significant differences in survival and lung function between lobar and whole lung transplant, indicating that size reduction is a valid option to consider. This study is limited by the sampling number, and results should be confirmed in a larger study. [ABSTRACT FROM AUTHOR]

This study compares the predictive ability of nine different types of motivational practices on the motivational orientation toward learning. Given the nature of undergraduate studies, identifying the most predictive motivational variables on learning orientation allows us to focus our efforts on those motivational practices to guide students to deploy their cognitive resources by focusing on learning and not only on obtaining good grades. The study included Chilean university students from health (n = 398) and education (n = 365) programs. A Bayesian multiple regression was carried out in both groups. The results show strong evidence of a specific effect of motivational practices on motivational orientation towards learning. Although the impact on motivational orientation toward learning may vary slightly across different fields of study, the primary predictors consistently are practices that emphasize importance and foster autonomy. The effect of utility-focused motivational practices is observed only within the predictive model for the group of health students., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Valenzuela et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objectives: To characterize clinical aspects, evaluate the diagnostic opportunity, and identify factors associated with mortality in patients hospitalized for tuberculosis (TB)., Methods: Retrospective study of patients admitted for TB to a Regional Hospital in Chile between 2011 and 2019., Results: 142 TB events required hospitalization in this period (38.2% of total cases). All risk groups were identified, with a significant increase in patients with diabetes mellitus. The pulmonary location was the most frequent (71.1%), followed by disseminated forms (16.2%). The sensitivity of microscopy smear in cases of pulmonary TB (isolated or combined) was 78.8% and lower in cases of bronchoalveolar lavage (58.3%). PCR was only occasionally applied (< 10%) with a sensitivity of 100% in sputum samples. Its use increased progressively and reached a positivity of 33% (6 out of 18 cases) in cases with negative sputum staining. The median time between symptom onset and diagnosis was prolonged (9 weeks), and 32.5% of all regional events were diagnosed at the hospital. Dose adjustments (22.1%), corticosteroid use (25%), and treatment interruptions were frequent (11%). Lethality reached 19%, and by multivariate analysis, only shock was associated with a fatal outcome., Conclusions: In this case series, the diagnosis of TB cases was delayed, scarcely diagnosed by molecular methods, highly concentrated at the hospital level, required admission in a large percentage of cases, and had a high case-fatality rate.

The main aim in this research was to validate a scale for measuring technostress in Chilean university students under the context of hybrid education. There were 212 university students as participants from the central-south zone of Chile. For measuring technostress manifestations, a technostress questionnaire for Chinese university professors and its adaptation for Spanish university students was used as a base instrument to adapt the scale. The exploratory and confirmatory factor analysis generated an adequacy of the psychometric scale by eliminating three items from the original scales but generated important changes by reordering the other 19 items into only three factors, establishing an important local difference with previous versions that contemplated five factors, but retaining as a central axis the stress produced by a misfit between the person and his or her environment. The resulting scale was based on factors such as Abilities-Demands Techno-Educational, Needs-Supplies Resources, and Person-People Factor. It also has a good internal consistency with a scale that allows for the continuation of technostress measurements in the local context; adding to studies on this topic which have already been carried out on diverse actors of the Chilean educational system; proposing a reliable and valid psychometric scale of technostress in Chilean university students; and giving researchers and academic managers the ability to know the adverse effects of the use of technologies and propose mitigation actions.

The Covid-19 pandemic has been responsible for millions of deaths worldwide. Patients with comorbidities- such as those on peritoneal dialysis (PD)- present higher morbidity and mortality than the general population. We prospectively evaluated all Chilean patients on PD (48 centres) and followed those who had Covid-19 from the beginning of the Covid-19 pandemic in Chile (March 2020) to January 2021 (start of vaccination campaign). We described demographic history, comorbidities, factors related to infection, need for hospitalisation and death due to Covid-19. During the study period, 106 adults on PD were infected by SARS-CoV-2, with a mean age of 53.1 (±16.3) and of which 53.9% were female. From that group, 54.8% required hospitalisation and 24.5% ( n = 26) died due to Covid-19. Most of the patients (63.4%) were infected at home and 22.8% during hospitalisation for other reasons. There was a significant association for Covid-19 mortality with: being ≥60 years old, diabetes, time on PD ≥5 years, need for hospitalisation and hospital-acquired infection. At 90 days of follow-up, all deaths associated to Covid-19 occurred before 40 days. We conclude that patients on PD without Covid-19 vaccination have a high mortality and need for hospitalisation associated to Covid-19. To avoid this negative outcome, it is necessary to intensify strategies to avoid contagion, especially in those ≥60 years old, with diabetes and/or ≥5 years spent on PD.

This article shows the levels of technostress in primary and secondary education teachers in Chile, in the context of educational telework that Chile has adopted in connection with the health crisis by COVID-19. The information has been collected with the use of the RED-TIC scale, previously used in this country, whose validity and reliability of the instrument has been treated, for this case, with confirmatory factorial analysis (CFA) with a national coverage sample of 3006 teachers. The results show that 11% of teachers reveal techno anxiety and 7.2%, techno fatigue. Combining both manifestations, we find that 6.8% of teachers are techno stressed. Finally, fatigue and anxiety factors are higher for female teachers.

Background: Laparoscopic liver resections (LLR) have been increasingly performed in recent years. Most of the available evidence, however, comes from specialized centers in Asia, Europe and USA. Data from South America are limited and based on single-center experiences. To date, no multicenter studies evaluated the results of LLR in South America. The aim of this study was to evaluate the experience and results with LLR in South American centers., Methods: From February to November 2019, a survey about LLR was conducted in 61 hepatobiliary centers in South America, composed by 20 questions concerning demographic characteristics, surgical data, and perioperative results., Results: Fifty-one (83.6%) centers from seven different countries answered the survey. A total of 2887 LLR were performed, as follows: Argentina (928), Brazil (1326), Chile (322), Colombia (210), Paraguay (9), Peru (75), and Uruguay (8). The first program began in 1997; however, the majority (60.7%) started after 2010. The percentage of LLR over open resections was 28.4% (4.4-84%). Of the total, 76.5% were minor hepatectomies and 23.5% major, including 266 right hepatectomies and 343 left hepatectomies. The conversion rate was 9.7%, overall morbidity 13%, and mortality 0.7%., Conclusions: This is the largest study assessing the dissemination and results of LLR in South America. It showed an increasing number of centers performing LLR with the promising perioperative results, aligned with other worldwide excellence centers.

The expanded use of information technology in education has led to the emergence of technostress due to a lack of adaptation to the technological environment. The purpose of this study is to identify the levels of technostress in primary and secondary education in 428 teachers using a RED-TIC questionnaire, of which skepticism, fatigue, anxiety, and inefficiency are the main components. For the empirical analysis of the data, principal component analysis (PCA) and confirmatory factor analysis (CFA) were used. The results show that 12% of Chilean teachers participating in the study feel techno-fatigued, 13% feel techno-anxious, and 11% present both conditions. Male teachers show a higher incidence of techno-anxiety and techno-fatigue than their female peers. It can be concluded that the questionnaire used is a reliable tool to evaluate the presence of technostress, and it manifests itself importantly in its components of techno-anxiety and techno-fatigue in Chilean teachers.

Syphilis during pregnancy has a high risk of congenital transmission with disastrous fetal consequences. Penicillin (PNC) is the only effective antimicrobial for the treatment of pregnant women with syphilis. Chilean guidelines do not consider desensitization to PNC in these women. We report two cases of pregnant women aged 32 and 23 years, with immediate allergy to PNC and syphilis who were safely and successfully desensitized using a four-hour intravenous protocol in the critical care unit and who subsequently received benzathine G PNC. An electronic survey was conducted among approximately 100 Clinical Pharmacists (CP) in the country. Of these, 16 answered and 13 reported having experience in drug desensitization, in at least five cases with PNC and none reported deaths or cardiorespiratory arrest. Desensitization to PNC can be carried out safely and in Chile, this alternative should be incorporated to the management of pregnant women with syphilis and immediate allergy to PNC, instead of using erythromycin.

In southern Chile, epidemiological studies have linked high levels of air pollution produced by the use of wood-burning stoves with the incidence of numerous diseases. Using a quasi-experimental design, this study explores the potential of participatory sensing strategies to transform experiences, perceptions, attitudes, and daily routine activities in 15 households equipped with wood-burning stoves in the city of Temuco, Chile. The results suggest that the experience of using a low-cost sensor improves household members' awareness levels of air pollution. However, the information provided by the sensors does not seem to improve the participants' self-efficacy to control air quality and protect themselves from pollution. The high degree of involvement with the participatory sensing experience indicates that the distribution of low-cost sensors could be a key element in the risk communication policies.

Fecal pollution source tracking (FST) studies the origin of fecal contamination and promotes action to eliminate it to improve human health and environmental sustainability. This work presents the temporal and spatial relations of human mitochondrial DNA (HmtDNA), fecal coliforms (FC) and live microbial biomass (ATP) in seawater during a hepatitis A outbreak among a human coastal population. The study area is approximately 100 km along the coastline of the Biobío Region in the southeastern Pacific (Humboldt Current System, Chile). Total data from the swash zone from summer 2015 to autumn 2016 show there were significant positive log-log correlations between FC and HmtDNA (R = 0.32) and ATP (R = 0.31). These correlations were highest during the austral spring of 2015 (R = 0.53 and 0.58 respectively), when HmtDNA also correlated significantly with ATP (R = 0.86). Maximum average values of the parameters measured in this season showed a temporal-spatial concordance with the peak in the number of hepatitis A cases among the nearby coastal population. FC correlated significantly with HmtDNA (R = 0.98) in the water column of the coastal zone close to Concepción Bay during the austral summer of 2016 and in the swash zone of the bay (R = 0.68) throughout the study period. Hepatitis A virus (HAV) has also been detected in organisms and seawater in Concepción Bay, which is consistent with the high incidence of hepatitis A among the coastal population. The concordance between human fecal pollution in the study area and a seasonal hepatitis A outbreak strongly suggests that HmtDNA and its relation with FC and ATP in the coastal zone of marine environments can be used as a proxy to evaluate the risk of outbreaks of thalassogenic diseases., (Copyright © 2019. Published by Elsevier B.V.)

Background: The APGAR-family scale is used for the assessment of family functioning in primary health care., Aim: To examine the psychometric properties of the family functioning scale APGAR-family, in a multi-ethnic sample of older Chilean adults., Material and Methods: The scale was applied to 800 participants aged more than 60 years, residing in rural areas of the regions of Arica and Parinacota and La Araucanía., Results: The Cronbach's alpha obtained was 0,992 for the scale composed of five items. The confirmatory factor analysis determined a unifactorial model, whose goodness of fit indices were satisfactory. Namely, weighted least square mean and variance adjusted-χ2 was 20.097 (p < 0.01), comparative fit index was 0.997, Tucker-Lewis index was 0.995 and Root Mean Square Error of Approximation was 0.079 (90% confidence intervals 0.049-0.091)., Conclusions: The APGAR-family is a reliable and appropriate instrument to be applied in older people in Chile, specifically in elderly people residing in rural areas who belong to the Aymara and Mapuche indigenous communities.

Background: The oral flagellated protozoan Trichomonas tenax has been associated with patients with periodontal disease. However, no recent studies have been conducted on the prevalence of T. tenax in Chile. The aim of this study was to determine the presence of T. tenax in patients with periodontal disease, admitted to the Dental Clinic of the University of Antofagasta, Chile, through Polymerase Chain Reaction (PCR) amplification of the beta-tubulin gene., Methods: An observational, cross-sectional study was conducted on 50 patients diagnosed with periodontal disease, 20 of them with gingivitis and 30 with periodontitis. T. tenax was identified by PCR amplification of the beta-tubulin gene. Associations between the protozoan and periodontal disease or the presence of risk factors to establish T. tenax infection were determined using the chi-square test and binary logistic regression analysis., Results: T. tenax was present in 28 out of 50 (56%) of patients with periodontal disease, and was more prevalent when associated with periodontitis (21 out of 30; 70%) than dental plaque-induced gingivitis (7 out of 20; 35%). Non-statistically-significant associations were observed between the presence of T. tenax and age, gender, smoking habit or diabetes. Statistically significant associations were observed between the presence of T. tenax and periodontal disease, and between T. tenax and the Periodontal Screening and Recording (PSR) index., Conclusion: T. tenax showed a high presence in patients with progressive states of periodontal diseases. Consequently, T. tenax detection is strongly recommended in patients with periodontal disease diagnosis and with a PSR index greater than 3.

The objective of this paper is to present the distance education's contribution to developing health promotion in Chile, through evaluation of a postgraduate certificate program for professionals, and a training course for nurse technicians working in primary healthcare, with an 8-month follow-up after program completion. The program methodology was participatory, interactive and reflective, with mentoring support, exercises, group work and discussions as well as content pertinent to the needs of practice. The evaluation was quali-quantitative with an analysis of the student profile, the implementation process, outcomes at the end of the training and impacts on workplace changes. The results showed a high rate of student approval (87 and 76%), good academic performance and a high level of satisfaction with the methodology and knowledge delivered. The participants' final projects were adapted to local work places realities and were implemented by 62.6% of technicians and 43% of professionals, in addition to changes in work practices that favor health promotion. The level of fulfillment of participants' expectations was very high and the most frequent barriers to implementing the final project were lack of time and personnel, along with minimal support from management and low prioritization of health promotion. This study shows the effectiveness of a distance training model for professionals and technicians that can reach the most remote parts of the country, where there is no access to presencial training, with an educational program centered on work activities and current health challenges., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Aim: To build a consensus among Chilean specialists on the appropriate management of patients with nonalcoholic fatty liver disease (NAFLD) in clinical practice., Methods: NAFLD has now reached epidemic proportions worldwide. The optimal treatment for NAFLD has not been established due to a lack of evidence-based recommendations. An expert panel of members of the Chilean Gastroenterological Society and the Chilean Hepatology Association conducted a structured analysis of the current literature on NAFLD therapy. The quality of the evidence and the level of recommendations supporting each statement were assessed according to the recommendations of the United States Preventive Services Task Force. A modified three-round Delphi technique was used to reach a consensus among the experts., Results: A group of thirteen experts was established. The survey included 17 open-ended questions that were distributed among the experts, who assessed the articles associated with each question. The levels of agreement achieved by the panel were 93.8% in the first round and 100% in the second and third rounds. The final recommendations support the indication of lifestyle changes, including diet and exercise, for all patients with NAFLD. Proven pharmacological therapies include only vitamin E and pioglitazone, which can be used in nondiabetic patients with biopsy-proven nonalcoholic steatohepatitis (the progressive form of NAFLD), although the long-term safety and efficacy of these therapies have not yet been established., Conclusion: Current NAFLD management is rapidly evolving, and new pathophysiology-based therapies are expected to be introduced in the near future. All NAFLD patients should be evaluated using a three-focused approach that considers the risks of liver disease, diabetes and cardiovascular events.

We investigated the production of ammonium by the photodegradation of dissolved organic matter (DOM) in the coastal upwelling system off central Chile (36°S). The mean penetration of solar radiation (Z1%) between April 2011 and February 2012 was 9.4 m, 4.4 m and 3.2 m for Photosynthetically Active Radiation (PAR; 400-700 nm), UV-A (320-400 nm) and UV-B (280-320 nm), respectively. Ammonium photoproduction experiments were carried out using exudates of DOM obtained from cultured diatom species (Chaetoceros muelleri and Thalassiosira minuscule) as well as natural marine DOM. Diatom exudates showed net photoproduction of ammonium under exposure to UVR with a mean rate of 0.56±0.4 µmol L(-1) h(-1) and a maximum rate of 1.49 µmol L(-1) h(-1). Results from natural marine DOM showed net photoproduction of ammonium under exposure to PAR+UVR ranging between 0.06 and 0.2 µmol L(-1) h(-1). We estimated the potential contribution of photochemical ammonium production for phytoplankton ammonium demand. Photoammonification of diatom exudates could support between 117 and 453% of spring-summer NH4(+) assimilation, while rates obtained from natural samples could contribute to 50-178% of spring-summer phytoplankton NH4(+) requirements. These results have implications for local N budgets, as photochemical ammonium production can occur year-round in the first meters of the euphotic zone that are impacted by full sunlight.

Unlabelled: Infectious salmon anemia (ISA) is a severe disease that affects farmed Atlantic salmon (Salmo salar), causing outbreaks in seawater in most salmon-producing countries worldwide, with particular aggressiveness in southern Chile. The etiological agent of this disease is a virus belonging to the Orthomyxoviridae family, named infectious salmon anemia virus (ISAV). Although it has been suggested that this virus can be vertically transmitted, even in freshwater, there is a lack of compelling experimental evidence to confirm this. Here we demonstrate significant putative viral loads in the ovarian fluid as well as in the eggs of two brood stock female adult specimens that harbored the virus systemically but without clinical signs. The target virus corresponded to a highly polymorphic region 3 (HPR-3) variant, which is known to be virulent in seawater and responsible for recent and past outbreaks of this disease in Chile. Additionally, the virus recovered from the fluid as well as from the interior of the eggs was fully infective to a susceptible fish cell line. To our knowledge, this is the first robust evidence demonstrating mother-to-offspring vertical transmission of the infective virus on the one hand and the asymptomatic transmission of a virulent form of the virus in freshwater fish on the other hand., Importance: The robustness of the data presented here will contribute to a better understanding of the biology of the virus but most importantly will constitute a key management tool in the control of an aggressive agent constantly threatening the sustainability of the global salmon industry.

Background: Health promotion in Chile is essential, considering its current epidemiologic status where chronic diseases are predominant., Aim: To report the evaluation of an on-line Diploma in health promotion for Primary Health Care professionals., Material and Methods: Two hundred sixty four professionals from all regions of the country (40% rural and 60% urban) took the Diploma. It lasted 8 months with 248 academic hours distributed in 5 modules with a total of 15 units. The program was evaluated with four surveys answered by the students (general description of participants, mid-term, final and follow-up)., Results: Students were highly satisfied with the program and especially with its interactive methodology which included tutorials, individual and group assignments, online discussions and a final project. The drawbacks were time restrictions and limited internet access. Ninety percent of students completed the course with an overall mean grade of 5.57 (out of a 1-7 scale). The follow-up survey showed that students implemented the new health promotion knowledge acquired, and put in practice their final assignment in their local counties. Also, most students improved their working conditions., Conclusions: The on-line interactive and participative methodology applied in this Diploma had positive results and the evaluation model can be applied in other health promotion on-line education programs.

Introduction: Children with neurological diseases that impose severe limitations on their mobility have a deficient quality of life (QL)., Aims: To study whether the QL of such patients improves with the application of a programme of audiovisual stimulation., Patients and Methods: A prospective study was conducted on nine children, six of whom were males (mean age: 42.6 ± 28.6 months), with severely limited mobility and who had been hospitalised for long periods. Two audiovisual stimulation programmes were produced and applied, together with videos, by means of a specially designed structure. The stimulus was applied twice a day for 10 minutes over 20 days. The first ten days the stimulus was carried out in a passive manner and the second block of ten days it was performed with the guidance of the observer. Biological, behavioural and cognitive variables were recorded and an adapted QL survey was applied., Results: Three cases of spinal muscular atrophy, two of congenital muscular dystrophy, two of myopathy and two with other conditions were diagnosed. Eight patients completed the follow-up. From the baseline point of view, they presented a regular QL (7.2 ± 1.7 points; median: 7.0; range: 6-10), which improved to good on finishing the therapy (9.4 ± 1.2 points; median: 9.0; range: 8-11), with an intra-individual difference of 2.1 ± 1.6 (median: 2.5; range: -1 to 4; CI 95% = 0.83-3.42; p = 0.006). Improved cognition and a favourable perception in the caregivers were detected. No changes took place in the biological or behavioural variables., Conclusions: Audiovisual stimulation can be used to enhance the quality of life of children with severely limited mobility.

The Lenga Estuary is one of the most industrialized sites in south central Chile where the historic operation of chlor-alkali plants resulted in large quantities of mercury (Hg) being deposited into the estuary. This historical contamination may still represent a risk to the biota in the estuary. To investigate this four macroinvertebrates, Neotrypaea uncinata (ghostshrimp), Elminius kingii (barnacle), Hemigrapsus crenulatus (shore crab) and Perinereis gualpensis (ragworm) were collected seasonally from three different sites in the Lenga Estuary and one in a reference estuary (Tubul Estuary), and analyzed for Hg and stable isotopes (δ(15)N and δ(13)C). Mercury concentrations in Lenga sediments ranged from 0.4 ± 0.1 to 13 ± 3 mg/kg, while those in Tubul sediments ranged from 0.02 ± 0.01 to 0.07 ± 0.09 mg/kg. Total Hg concentrations of invertebrates were significantly different between estuaries (p<0.05), but not by species or season for each estuary (p>0.05). In contrast, organic Hg concentrations were different by species and season with shore crab muscle tissues exhibiting the greatest percent difference. Site-specific relationships demonstrated that total Hg concentrations in ragworm best reflected the total Hg sediment mercury concentrations. Signatures of δ(13)C were correlated to the organic Hg % rather than total Hg. This suggests that organic Hg concentrations in these species were related to the carbon sources., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: Treatment requirements in hepatolithiasis may vary and may involve a multidisciplinary approach. Surgical resection has been proposed as a definitive treatment., Objectives: This study aimed to evaluate the clinical results of anatomic liver resection among Chilean patients with hepatolithiasis., Methods: An historical cohort study was conducted. Patients who underwent hepatectomy as a definitive treatment for hepatolithiasis from January 1990 to December 2010 were included. Patients with a preoperative diagnosis of cholangiocarcinoma were excluded. Preoperative, operative and postoperative variables were evaluated., Results: A total of 52 patients underwent hepatectomy for hepatolithiasis. The mean ± standard deviation patient age was 49.8 ± 11.8 years (range: 24-78 years); 65.4% of study subjects were female. A total of 75.0% of subjects had a history of previous cholecystectomy. The main presenting symptom was abdominal pain (82.7%). Hepatic involvement was noted in the left lobe in 57.7%, the right lobe in 34.6% and bilaterally in 7.7% of subjects. The rate of postoperative clearance of the biliary tree was 90.4%. Postoperative morbidity was 30.8% and there were no postoperative deaths. Three patients had recurrence of hepatolithiasis, which was associated with Caroli's disease in two of them. Overall 5-year survival was 94.5%., Conclusions: Anatomic liver resection is an effective treatment in selected patients with hepatolithiasis and is associated with low morbidity and no mortality. At longterm follow-up, anatomic hepatectomy in these patients was associated with a lower rate of recurrence., (© 2012 International Hepato-Pancreato-Biliary Association.)

Purpose: To assess risk factors for alveolar osteitis., Materials and Methods: A prospective nested case-control study was conducted in an urban community dental clinic in Valdivia, Chile. A cohort of 1,355 patients who underwent dental extractions was included. Eight predictor variables (risk factors), namely patient gender, hygiene, tooth location, previous surgical site infection, traumatic extraction, systemic diseases, alcohol consumption, and tobacco use, were considered in a risk factor model. A binary regression logistic analysis was performed to determine significant associations., Results: In total 1,302 participants completed the follow-up. Eighty incident case patients with alveolar osteitis and 80 matched control patients were included. A statistically significant association was found between traumatic extraction (odds ratio [OR], 13.1; 95% confidence interval [CI], 5.4 to 31.7), tobacco smoking after extraction (OR, 3.5; 95% CI, 1.3 to 9.0), previous surgical site infection (OR, 3.3; 95% CI, 1.4 to 7.7), and the development of alveolar osteitis., Conclusions: Previous surgical site infection, traumatic extraction, and tobacco smoking are associated with an increased risk of alveolar osteitis., (Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Introduction: The ano-rectal pathology (ARP) is the most common surgical condition in patients with human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS). Our aim was to determine the current prevalence and clinical characteristics of the ARP in patients with HIV/AIDS in clinical control in the infectious diseases unit of the Hernán Henríquez Aravena Hospital in Temuco., Study Design: Cross section. Location and period: Infectious Diseases Unit of the hospital during the month of June 2010., Inclusion Criteria: Patients with HIV/AIDS under control in the unit, medical records were analyzed and complete physical examination was performed., Results: In the period of study 384 patients were in control in the unit. Fifty had ARP which is a prevalence of 13%. Anal condyloma disease and hemorrhoidal disease were the most common diseases. Most patients (76%) were on antiretroviral therapy with good clinical response., Conclusion: The prevalence of ARP in HIV/AIDS patient has increased in recent years. This study shows a change in the pattern of presentation, being anal condyloma the most common ARP.

Given the increasing travel of pregnant women from areas were Trypanosoma cruzi is endemic, the congenital transmission of the parasite has become a global public-health problem. In a recent pilot study, which ran in Chile from 2006 to 2010, three strategies for exploring and managing T. cruzi-infected mothers and their infected or uninfected neonates were investigated. Any protocols applied to the investigation of such mother-and-child pairs need to include the detection of infection in pregnant women, the detection of infection, if any, in the children born to the women, the appropriate treatment of the infected neonates, and the serological-parasitological follow-up of all of the neonates until their medical discharge.

Background: Aortic valve stenosis is the most prevalent valvulopathy in the elderly, but it is frequently undertreated., Aim: To assess early and long term results of valve replacement with bioprostheses in patients 70 years old or older with aortic stenosis., Patients and Methods: A review of the database of the Cardiovascular Surgery Service of our hospital, for the period 1990-2007, identified 156 patients with aortic valve stenosis, aged 76.7 ± 4.5 years (67% males), that were subjected to an aortic valve replacement with bioprosthesis. Seventy eight (50%) were in functional class III-IV. Six patients had emergency surgery. In 67 patients (43%) coronary artery bypass graft were performed. Long term mortality was ascertained obtaining death records from Chilean death registry., Results: Operative mortality was 3.2% (5 patients). Four patients (2.6%) required a reoperation due to bleeding. The mean follow up was 66 ± 41 months. The survival rate at 1, 3 and 5 years was 94%, 88% and 80%, respectively. Forty two patients (27%) were 80 years old or older. In this sub-group, 1 patient (2.3%) died during the peri operative period and the estimated survival rate at 1, 3 and 5 years was 97%, 92%, and 80%, respectively. Multivariate risk analysis, for the whole group, identified low ejection fraction and concomitant coronary artery bypass graft surgery as predictors of late mortality., Conclusions: Aortic valve replacement for aortic stenosis with bioprostheses in patients 70 years old or older had low perioperative mortality and morbidity and a good long term survival.

Background: Donald Ross introduced the pulmonary autograft for aortic valve replacement with reconstruction of the right ventricular outflow tract with a homograft. Despite its advantages over conventional valve prostheses, the Ross Operation is performed in a minority of patients who need an aortic valve replacement throughout the world., Aim: To report the operative and long term results of a series of patients subjected to Ross operation in Chile., Patients and Methods: Between 1996 and 2006, 131 patients aged 35+/-11 years (62% males) were subjected to an aortic root replacement with a pulmonary autograft and reconstruction of the right ventricular outflow tract with a pulmonary homograft. Seventy percent had congenital valve disease. Associated procedures were done in 39%. Patients were followed for a mean of 56+/-30 months., Results: Operative mortality was 2.3%. Two patients had the autografts replaced intraoperatively because of tears in the proximal suture line and one within a month of the operation after suffering autograft endocarditis. At last follow up all patients are in functional class 1 or 2. Autograft reoperations were done in two patients who developed dilation with valve regurgitation (both had aortic regurgitation as primary indication for aortic valve replacement). Three patients required reoperation for pulmonary homograft dysfunction. Another three patients had uneventful pregnancies with normal newborns. Actuarial freedom from any reoperation at 10 years is 93%., Conclusions: The Ross Operation has low operative morbidity and mortality with excellent long term results. Reoperations have been rare within 10 years of follow up both for the autograft or the homograft.

Unlabelled: Amphotericin B deoxycholate is associated with infusion-related toxicity and renal toxicity., Purpose: To evaluate medical indications of this compound in a tertiary care center, analyze adverse reactions, infusion protocols and outcome of treated patients., Patients and Methods: Retrospective analysis of 39 treatments indicated in 33 patients during 2007, exploring indications, infusion protocols and renal protective measures, infusion-related adverse reactions, nephrotoxicity, hypokalemia and outcomes., Results: On average, therapy lasted 12 days (2 to 39) and reached 600 mg of accumulated dose (100 to 1950) respectively. 24-hours infusions were applied in 63.2% of prescriptions and 35.9% received a 4-6 hour infusion schedule. In addition, 36.8% received daily a saline infusion before amphotericin. Adverse reactions were observed in 40% of treatments, predominating fever (25%). Nonetheless, nephrotoxicity was infrequent (9.4%), of low magnitude, only affecting patients without previous renal disease, and not requiring dialysis. Hypokalemia developed in 21.6% of treatments. More than half of medical indications were empirical (59%), for presumed infections by either filamentous fungi or yeasts. In the subgroup with microbiological information, main indications were invasive aspergillosis (15.4% of total), systemic candidiasis (12.8%) or meningeal cryptococcosis (10.3%). A favorable response was registered in 41%, and only 48.5% of patients survived. In a multivariate analysis, only age > 60 years remained as an independent factor for developing infusion-related adverse reactions. In the same manner, a SOFA score > 3 and corticosteroids administration at the same time than amphotericin B, were independently associated to a fatal outcome., Conclusion: infusion-related adverse reactions are frequent during amphotericin B deoxycholate therapy, but renal toxicity is occasionally observed. Amphotercin B was used mainly as empirical therapy in this study.

In this fifth part of Guidelines for Chagas disease, diagnostic techniques for Trypanosoma cruzi infection in humans are reviewed, the interpretation of laboratory results and an algorithm for laboratory diagnosis in immunocompetent hosts are presented. Chagas disease may be diagnosed by three kinds of techniques: direct, which allow detect the presence of the parasite in different kind of samples; indirect, based on the search of immune specific response against T. cruzi antigens and molecular, which detect parasite genetic material. Direct techniques are utilized mainly in acute phase of disease, as the parasite is present in blood of infected host. These techniques do not require be confirmed by other methods. For chronic undetermined phase and for symptomatic phase it is recommended to use indirect techniques; generally, immunoassay techniques (ELISA) that detect IgG antibodies directed against T. cruzi antigens are performed. As false positive results are possible, a positive or undetermined result must be confirmed by at least another technique (indirect immunofluorescence or indirect hemmaglutination). In Chile, confirmation of infection is performed by the Instituto de Salud Pública National Reference Laboratory or at surrogate centers. Molecular methods may be used to make the diagnosis in acute or chronic phase of infection, with more accuracy in the acute phase, and it is mainly recommended to diagnose vertical transmission of T. cruzi as early diagnosis of congenital infection increases the possibility to cure the sibling and besides it is a good marker to evaluate the effectiveness of treatment.

In this chapter it is emphasized the importance to guarantee safety and high quality blood transfusions. Besides, the following topics are analyzed: the importance of Trypanosoma cruzi infection acquired by blood transfusions, the obligatory screening implemented in Chilean blood banks and serological diagnostic techniques used that for, the seroprevalence observed, the importance to confirm results and methods recommended in this purpose and, to notify the donor once the infection is confirmed. In addition a facsímil of a letter used to notify the positive donor is included as guidelines to make advice after, attaching a pro-forma of clinical-epidemiological registration to refer the donor to medical evaluation and treatment.

Apnea is a common problem that causes significant parental anxiety. The aim of this study was to describe polysomnographic findings in infants who were referred over a 4-year period for an apnea and/or cyanotic event. Our hypothesis was that most infants with apnea or cyanosis events will have normal polysomnography (PSG). In total, 320 patients younger than 2 years old were recruited sequentially and prospectively. Patients underwent a day or overnight PSG by computerized polysomnograph; 78% of studies were performed with pH probe in situ. Subjects' ages ranged from 10 days to 21 months (55% male and 84% full-term babies); 55% and 74% were younger than 3 and 6 months, respectively. The average total sleep time was 473.4 min (SD, 52.3), with mean sleep efficiency of 83.5%. The distribution of sleep stages was 56.5% active, 38.5%, quiet and 5.1% indeterminate sleep. Sixty-nine percent (n = 220) of PSG studies were done overnight. There were significant differences in average sleep efficiency (78.1% vs. 83.3%) and REM sleep time (63.6% vs. 59.1%) between PSGs done during the day and overnight (P < 0.05). In total, 34 patients with apneas were studied. The median apnea index for the whole study population was 1.01 (range, 0.1-9.1). In conclusion, our study showed a high prevalence of normal polysomnographic findings in infants referred because of apnea and/or cyanotic events. New clinical prospective studies should be conducted to evaluate whether there is a correlation between PSG findings and outcome at follow-up of infants with a history of apnea and cyanosis., ((c) 2006 Wiley-Liss, Inc.)

Background: Immune response is impaired in the elderly. Our aim was to study the effects of a special nutritional formula on the immune response and response to influenza and pneumococcal vaccination in elderly subjects., Methods: Sixty healthy subjects aged > or = 70 years, with a Mini Mental score > or = 22 were studied. Half of the subjects received a special nutritional formula (in addition to the regular diet) providing, among other nutrients, 480 kcal, 31 g proteins, 120 IU vitamin E, 3.8 microg vitamin B12, 400 microg folic acid, 10(9) cfu Lactobacillus paracasei (NCC 2461), and 6 g of fructo-oligosaccharides. At 4 months of follow-up, subjects were vaccinated against influenza and pneumococcus. Lymphokine production by mononuclear cells (PBMC), lymphocyte subpopulations, and natural killer cell (NK) activity were measured at baseline and 4 months of follow-up (before vaccination). Antibodies against influenza and pneumococcal antigens and flu-stimulated production of interferon gamma and interleukin-2 by PBMC were measured at 4 and 6 months. Skin response to 7 recall antigens and body composition were assessed at baseline and at 4 and 12 months. All infections occurring during the study period were recorded., Results: NK activity increased in supplemented subjects and decreased in nonsupplemented individuals. Interleukin-2 production by PBMC and the proportion of T cells with NK activity decreased in controls and did not change in supplemented subjects. Supplemented subjects reported less infections than nonsupplemented individuals (in 13% and 22% of scheduled visits, respectively; p = .02)., Conclusions: This nutritional supplement increased innate immunity and protection against infections in elderly people.

Background: To establish the relationship between sleep apnoea and gastro-oesophageal reflux in infants and describe the clinical, demographic and pHmetric profile and the characteristic of the sleep polysomnography with a pH probe., Methods: A total of 102 consecutive patients were evaluated. Parents were requested to fill out a questionnaire about symptoms and previous therapy. Gastro-oesophageal reflux was considered abnormal when the percentage of time with pH less than 4 was higher than 4% of total sleep time., Results: A total of 102 infants were enrolled, 53% males. Seventy-four per cent of the infants were full-term babies. At the moment of the polysomnography, the mean age of the sample was 2.6 months. Suspicion of apnoea was the most common clinical diagnosis prior to the study. Only two infants have abnormal electroencephalogram. Mild gastro-oesophageal reflux was seen in 37 (36%) infants, while 22 (21.5%) did not have any reflux episode, and the remaining 43 (42%) infants had reflux index in the pathologic range. Only one patient had an unequivocal temporal relationship between acid oesophageal reflux and respiratory pause with oxygen desaturation., Discussion: Infants with history of apnoea or acute life threatening event frequently had gastro-oesophageal reflux episodes which did not correlated with respiratory events, suggesting that gastro-oesophageal reflux and apnoea often occur in the same infant as two separate events.

In August-December 1992, 500 diaphragm muscle samples taken at random from people who were autopsied at the Santiago Medico-Legal Service, were submitted to phototrichinoscopy to search for encysted larvae of Trichinella spiralis. For each sample seven small pieces were examined. Three hundred and eighty nine (77.8%) cadavers corresponded to males and one hundred and eleven (22.2%) to females. Ages ranged from 1 to 90 years. Ten (2.0%) of the individuals examined resulted positive, the higher frequencies corresponding to individuals over 20 years of age. The prevalence rate of T. spiralis infection found is rather similar to those detected in 1966-1967, 1972 and 1982, with percentages of 2.2, 3.4 and 2.8 respectively.