LIFE-COURSE MULTI-DISCIPLINARY PREDICTORS OF DEMENTIA AMONG OLDER ADULTS

The incidence of dementia is rapidly increasing. Identifying risk factors for dementia may help improve risk assessment, increase awareness for risk reduction, and identify potential targets for interventions. We use a life-course multi-disciplinary modeling framework to examine leading predictors of incident dementia (ID). We use the Health and Retirement Study (HRS) to measure 57 exposures across 7 different domains: (1) demographic, (2) adverse childhood socioeconomic and psychosocial, (3) adverse adulthood experiences, (4) adult socioeconomic status, (5) health behaviors, (6) social connections, and (7) adult psychological conditions. Our outcome is ID (over 8-years) operationalized using Langa-Weir classification for adults aged 65+ years who meet criteria for cognitively normal at the baseline when all exposures are measured (Nf 1,622 in testing set and Nf1,460 in validation set). We compare standard methods (Logistic regression) with machine learning (ML) approaches (Lasso, Random Forest) in identifying highly predictive exposures across the risk domains of interest. Standard methods identified lower education, childhood financial duress, and pessimism as among the leading factors associated with ID. Psychological factors explained the highest variance for ID, followed by adult socioeconomic and adverse childhood factors. However, ML techniques differed in their identification of (1) predictors and (2) factors predictive importance. The findings emphasize the importance of upstream risk factors and the long-reach of childhood experiences on cognitive health. The ML approaches highlight the importance of life-course multi-disciplinary frameworks for improving dementia risk assessment. Further investigations are needed to identify how complex interactions of life-course risk factors can be addressed through interventions.

Assessing the growth of Arctic charr (Salvelinus alpinus) (Linnaeus, 1758) in four salinities, under experimental conditions

Studies in Salvelinus alpinus, Arctic charr, indicate that it has a low capacity to hyposmorregulatory or adaption to sea in winter periods in Arctic waters. The investigation finds to determinate the rank optimum of salinity to can cultivate this species at Chile. The weight adequate was determined to join on the sea by analysis of gill Na+, K+-ATPase activity, that it was found between the ranks 80-130 g, with 14.5 U/mg. It underwent evaluation of fish growth of 72 g salinities from 0 (control), 18, 25 and 33 g/L (sea water) for 94 days. The results indicate that the largest increases were obtained in brackish water. T18 g/L and T25 g/L achieved growth of 25% and 19% on day 94 and term sampling respectively. It is important to mention that the 8% that survived in seawater introduced percentages growth 16.6% equivalent to brackish water and control. These results suggest that Salvelinus alpinus can grow in seawater, with levels of Na+, K+-ATPase similar to those submitted by Salmo salar with a weight not less than 80 g.

A New mHealth application to support treatment of sleep apnoea patients

Introduction Continuous positive airway pressure (CPAP) is the first-choice treatment for obstructive sleep apnoea (OSA), but adherence is frequently suboptimal. Innovative, patient-centred interventions are, therefore, needed to enhance compliance. Due to its low cost and ubiquity, mobile health (mHealth) technology seems particularly suited for this purpose. We endeavoured to develop an mHealth application called "APPnea," aimed at promoting patient self-monitoring of CPAP treatment. We then assessed the feasibility and acceptability of APPnea in a group of OSA patients. Methods Consecutive OSA patients used APPnea for six weeks. APPnea gave patients daily reminders to answer three questions about their OSA treatment (CPAP use, physical activity, and diet) and prompted them to upload their body weight weekly. Answers were saved to a secure server for further analysis. After completing the study, patients gave their anonymous opinions about APPnea. Results We enrolled 60 patients with OSA receiving CPAP treatment. The mean age was 56 ± 10 years and the apnoea-hypopnea index was 47 ± 25 events/hour. In total, 63% of participants completed the daily questionnaire for more than 66% of the study period. Objective CPAP compliance was generally high (5.3 ± 1.6 hours/night). In a subset of 38 patients naïve to CPAP, those who used APPnea regularly had significantly higher CPAP compliance. Satisfaction levels were high for the majority of users. Conclusion This mHealth intervention is not only feasible but also satisfactory to patients. Although larger randomized trials and cost-effectiveness studies should be performed, this study shows that APPnea could promote participation and improve compliance among patients with OSA, thereby improving outcomes.

[Evaluation of predictability and refractive changes in pediatric pseudophakia]

OBJECTIVE

Evaluate the predictability of the postoperative refraction and refractive changes in pediatric pseudophakia.

METHODS

Prospective, longitudinal follow-up on patients under the age of 15 years operated on for a cataract with intraocular lens, with 5 continuous years of follow-up. The patients were divided into 4 groups according to age at the time of the surgery: group from 0 to 2 years old, from 3 to 5 years old, from 6 to 8 years old, and 9 years and over. Error prediction and refractive change were studied. Statistical analysis was performed using the Student t and ANOVA test.

RESULTS

A total of 60 eyes were included (44 patients). No significant differences were found between the unilateral and bilateral group. The prediction error in the 0 to 2 years group was 1.5±1.8 D, significantly higher than in the other groups (ANOVA P=.01). Refractive change in 5 years of the group of 0 to 2 years was -4.7±3.4 D (ANOVA P=.0002), while in the other groups it was significantly lower, with no differences between them.

CONCLUSIONS

The 0 to 2 years group was less hyperopic than expected, 100% within the accepted of 2 standard deviations, but with a high variability. The refractive change observed in this group coincides with previous reports that the largest growth and increase in axial length occurs during the first 2 years. The calculation and use of an IOL in children has a better immediate refractive prediction, and at long term in those older than 2 years of age.

Evaluation of PCR for cutaneous leishmaniasis diagnosis and species identification using filter paper samples in Panama, Central America

Cutaneous leishmaniasis (CL) is a major vectorborne disease in Panama. In this study, the diagnostic performance and usefulness of two DNA extraction procedures from skin scraping samples collected on FTA filter paper for subsequent PCR diagnosis of CL was evaluated. A positive CL laboratory diagnosis was based on a positive parasitological test (Giemsa-stained smears or in vitro culture) and/or positive PCR test performed from skin scrapings collected in TE buffer (PCR-TE). Of 100 patients with skin lesions suggestive of CL, 82 (82%) were confirmed as CL positive. The sensitivity was calculated for each of the PCR approaches from samples collected on filter paper. The highest sensitivity was achieved by PCR-FTA processed by Chelex 100 (PCR-Chelex) (0.94). PCR-FTA extracted using the FTA purification reagent presented a lower sensitivity (0.60). Good concordance between routine PCR-TE and PCR-Chelex was observed (percent agreement=0.88, κ index=0.65). In conclusion, use of FTA filter paper for skin scraping collection combined with PCR is a reliable and convenient method for CL diagnosis in Panama, with comparable performance to the routine PCR method and with improved sensitivity compared with those of conventional parasitological methods.

Dengue virus identification by transmission electron microscopy and molecular methods in fatal dengue hemorrhagic fever

Dengue virus is the most significant virus transmitted by arthropods worldwide and may cause a potentially fatal systemic disease named dengue hemorrhagic fever. In this work, dengue virus serotype 4 was detected in the tissues of one fatal dengue hemorrhagic fever case using electron immunomicroscopy and molecular methods. This is the first report of dengue virus polypeptides findings by electron immunomicroscopy in human samples. In addition, not-previously-documented virus-like particles visualized in spleen, hepatic, brain, and pulmonary tissues from a dengue case are discussed.

Production, partial characterization and mass spectrometric studies of the extracellular laccase activity from Fusarium proliferatum

Benzyl alcohol and starch-free commercial wheat bran were effective inducers of the laccase activity in cultures of Fusarium proliferatum (MUCL 31970). Initial pH value in the cultures was also an overriding factor for increasing its production. By gel permeation high-performance liquid chromatography, the enzyme eluted as an apparently homogeneous peak with a molecular mass of 54 kDa, but by isoelectrofocusing, two proteins with pI values of 5.17 and 5.07 were revealed. Two different phenoloxidase activities were also detected after nondenaturing polyacrylamide gel electrophoresis. By matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS), both proteins showed unique fingerprints, so they were classifiable as isozymes, and were named laccase 1 (Lac1, pI 5.17) and laccase 2 (Lac2, pI 5.07). No clear matches were found when compared with other proteins. The tandem mass spectrometry of some peptides from both isozymes reanalyzed by nanoelectron ionization-ion trap-mass spectrometry (nESI-IT-MS) confirmed their unique character. The following interesting properties, particularly its stability at alkaline pH, make this laccase a promising industrial enzyme for biotechnological applications: maximum activity at 60 degrees C, thermal stability for 2 h at 40 degrees C, optimum pH 3.5 (km=62 microM) measured on 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulfonate), and pH stability 4-8 (75% stability at pH levels 2.2 and 9) for 2 h at 25 degrees C.