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Although both obesity and ageing are risk factors for cognitive impairment, there is no evidence in Chile on how obesity levels are associated with cognitive function. Therefore, the aim of the present study was to investigate the association between adiposity levels and cognitive impairment in older Chilean adults. This cross-sectional study includes 1384 participants, over 60 years of age, from the Chilean National Health Survey 2009–2010. Cognitive impairment was evaluated using the Mini-Mental State Examination. BMI and waist circumference (WC) were used as measures of adiposity. Compared with people with a normal BMI, the odds of cognitive impairment were higher in participants who were underweight (OR 4·44; 95 % CI 2·43, 6·45; P < 0·0001), overweight (OR 1·86; 95 % CI 1·06, 2·66; P = 0·031) and obese (OR 2·26; 95 % CI 1·31, 3·21; P = 0·003). The associations were robust after adjustment for confounding variables. Similar results were observed for WC. Low and high levels of adiposity are associated with an increased likelihood of cognitive impairment in older adults in Chile.
To understand non-adherence to medically recommended diets among Mayans with diabetes.
Using partially sequential mixed methods, questionnaires, semi-structured brief and in-depth interviews were applied. Questionnaire data were analysed with Pearson’s χ2 and Student’s t tests and qualitative interviews with grounded theory microanalysis.
Rural, predominantly Mayan communities in Chiapas, Quintana Roo and Yucatan, Mexico, 2008–2012.
Purposive sample of Mayans with type 2 diabetes; using public health care; 168 women and twenty-seven men; age 21–50+ years.
Participants understood diabetes as caused by negative emotions, divine punishment, revenge via spells, chemicals in food and high sugar/fat consumption. Eliminating corn, pork, sugary beverages and inexpensive industrialized foods was perceived as difficult or impossible. More Mayans reporting not understanding physician instructions (30 v. 18 %) reported difficulty reducing red meat consumption (P = 0·051). Non-adherence was influenced by lack of patient–provider shared knowledge and medical recommendations misaligned with local culture. Men whose wives prepared their meals, women who liked vegetables and young adults whose mothers prepared their meals reported greater adherence to dietary recommendations. Partial adherents said it made life tolerable and those making no physician-recommended dietary changes considered them too restrictive (they meant ‘starving to death’). Over half (57 %) of participants reported non-adherence; the two principal reasons were dislike of recommended foods (52·5 %) and high cost (26·2 %).
Adherence to dietary regimens in diabetes treatment is largely related to social and cultural issues. Taking cultural diversity, food preferences, local food availability and poverty into consideration is essential when developing health-promotion activities related to diabetes.
The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favourable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of global (astrospheric), and local (atmospheric and surface) environments of exoplanets in the habitable zones (HZs) around G-K-M dwarf stars including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favourable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro)physical, chemical and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the HZ to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field in light of presentations and discussions during the NASA Nexus for Exoplanetary System Science funded workshop ‘Exoplanetary Space Weather, Climate and Habitability’ and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.
To examine the frequency of television (TV) food and beverage advertisements (F&B ads) to which children (4–11 years) are likely exposed and the nutrient profile of products advertised.
TV broadcasting between September and November 2016 was recorded (288 h of children’s programming; 288 h of family programming) resulting in 8980 advertisements, of which 1862 were F&B ads. Of those, 1473 could be classified into one of the seventeen food groups, and into permitted/non-permitted according to the WHO-EU nutrient profile model. Persuasive marketing techniques used were also identified.
TV programming was recorded for four weekdays and four weekend days, between 06.00 and 00.00 hours (576 total hours), for four channels (two national and two cable), in Costa Rica.
Mean (sd) number of F&B ads/h was greater in cable than national channels (3·7 (0·4) v. 2·8 (0·4), P < 0·05) and during children’s peak viewing hours (4·4 (0·4) v. 2·9 (0·3)). Of F&B ads classified with WHO-EU nutrient profile model (n 1473, 71·1 %), 91·1 % were non-permitted to be marketed to children. Categories most frequently advertised were ready-made/convenience foods (16 %), chocolates/confectionery/desserts (15 %), breakfast cereals (14 %), beverages (15 %), edible ices (9 %) and salty snacks (8 %). Non-permitted F&B ads were more likely to use promotional characters, brand benefit claims, and nutrition and health claims than permitted F&B ads.
Children watching popular TV channels in Costa Rica are exposed to a high number of unhealthy F&B ads daily. Our findings help justify the need for regulatory actions by national authorities.
OBJECTIVES/SPECIFIC AIMS: The Title V Cooperative Project of the UPR-MSC and UCC has demonstrated that educational interventions in CTR are very effective in fulfilling the objective of promoting awareness, stimulate interest and increase the knowledge, skills and opportunities, to US, GS and F (participants) in CTR. METHODS/STUDY POPULATION: The training sessions (TS) offered through the Title V initiative have become an engine for the involvement in CTR for participants from higher education institutions island-wide. TS consisted of cycles –level 1 and 2–: Research Education Towards Opportunities (RETO,I,II) and Mentorship Offering Training Opportunities for Research (MOTOR,I,II), ending in the formation of the Clinical and Translational Mentoring Teams (CTMT)s, in which participants, paired by their research interests, were mentored by a well-established CT researchers in their research project, to be developed in the Intensive Development and Experiences in Advancement of Research and Increased Opportunities (IDEARIO). RESULTS/ANTICIPATED RESULTS: Up to date, 4 TS-level 1 and 2 TS-level 2 were offered. Eighty (80) participants completed level 1, distributed: 42 (52.5%) US in RETO, 21 (26.25%) GS and 17 (21.25%) F in MOTOR and 17 participants completed level 2, distributed: 4 (23.52%) US in RETO, 6 (25.29%) GS and 7 (41.17%) F in MOTOR. From which, 15, with 8 CT researchers, formed 5 CTMTs in different research areas – cardio, neuro, liver, renal, Zika–. DISCUSSION/SIGNIFICANCE OF IMPACT: US, GS and F were integrated in the active process throughout educational levels for their development in CTR.
Composites from carbon nanotubes and polymers have been synthesized and studied. The composites were obtained joining carbon nanotubes with polymethyl methacrylate, nylon-6 and polystyrene. The materials were observed through scanning electron microscopy to evaluate the carbon nanotubes dispersion in the polymeric matrices. FTIR and Raman spectroscopies were used to analyze the interactions among functionalized and non-functionalized multiwalled carbon nanotubes and polymers, demonstrating affinity and peculiar spectra behaviors for each composite with different carbon nanotubes loads.
This work presents the synthesis and characterization of TiO2 nanotubes (NTT) with chitosan (CS). In a first stage, electrochemical anodization of titanium foils was used to generate NTT in a membrane-type arrangement. From these experiments, suitable experimental conditions were selected. In a second stage, the synthesized NTT were detached from the titanium foils by sonication. In the third stage, the detached NTT were dispersed in an acid solution containing CS in various concentrations. Finally, the nanotubes-chitosan (NTT/CS) samples were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared Spectrometry (FTIR). Our results showed that the NTT presented very regular tube morphology with -OH and Ti-O- functional groups on the surface. The interaction of NTT and chitosan was enhanced by increasing the time of contact during the synthesis of the titanium composites.
PA6 and PMMA polymers with different MWCNTs addition (5, 7 and 9 wt %) were synthetized through casting solution, resulting in improvement properties in contrast to pristine polymers. SEM images showed the MWCNTs embedded into polymeric matrices. D, G and G´ bands of MWCNTs were confirmed by Raman spectroscopy and functional groups observed in both nanocomposites by FTIR demonstrated a strong interaction. A significant increasing in electrical conductivity and microhardness was observed in all the nanocomposites. Major microhardness values were obtained in MWCNTs/PA6 (50 HV) however the MWCNTs/PMMA nanocomposites showed the highest electrical conductivity value (6.4×10-4 S/cm).
We determined the molecular epidemiology of Bordetella pertussis isolates to evaluate its potential impact on pertussis reemergence in a population of Mexico. Symptomatic and asymptomatic cases were included. Pertussis infection was confirmed by culture and real-time polymerase chain reaction (PCR). Selected B. pertussis isolates were further analysed; i.e. clonality was analysed by pulsed-field gel electrophoresis (PFGE) and ptxP-ptxA, prn, fim2 and fim3 typing was performed by PCR and sequencing. Out of 11 864 analysed samples, 687 (5.8%) were positive for pertussis, with 244 (36%) confirmed by both culture and PCR whereas 115 (17%) were positive only by culture and 328 (48%) were positive only by PCR. One predominant clone (clone A, n = 62/113; 55%) and three major subtypes (A1, A2 and A3) were identified by PFGE. All 113 selected isolates had the allelic combination ptxP3-ptxA1. The predominant clone A and the three major subtypes (A1, A2 and A3) corresponded to the emerging genotypes ptxP3-ptxA1-prn2-fim2-1-fim3-2 and ptxP3-ptxA1-prn2-fim2-1-fim3-1. In conclusion, the presence of an endemic clone and three predominant subtypes belonging to the genotypes ptxP3-ptxA1-prn2-fim2-1-fim3-2 and ptxP3-ptxA1-prn2-fim2-1-fim3-1 were detected. This finding supports the global spread/expansion reported for these outbreaks associated genotypes.
OBJECTIVES/SPECIFIC AIMS: Responding to the need and interest of students and faculty of the UHSP in learning about CTR, the Title V Cooperative Project between UPR-MSC and UCC, developed and offered a training cycle (TC) in CTR. METHODS/STUDY POPULATION: Undergraduate students (US), undergraduate faculty (UF), and graduate students (GS) were invited to register in: Research Education Towards Opportunities (RETO) and Mentorship Offering Training Opportunities for Research (MOTOR), which consisted of 20 hours of training in CTR, with interdisciplinary sessions in: Introduction and preparation of a presentation in CTR; Identify, interview and share a presentation of a CT researcher; participation in conferences and a summer camp in CTR. At the end of the TC, surveys—satisfaction and needs assessment—for training in CTR were administered. RESULTS/ANTICIPATED RESULTS: Thirty-three (33) registered in the TC, distributed: 13 (39.39%) US in RETO, 12 (36.36%) GS and 8 (24.24%) UF in MOTOR. Of these, 25 (75.75%) answered and submitted the on-line surveys and received a completion certificate. All (100%) were satisfied with the TC, and for 96% of the respondents, their expectations were fulfilled, and will continue in the TC. They selected critical review, scientific communication, and cultural diversity as thematic areas of interest. In addition, 60% of them selected neuroscience, cancer and medical imaging as main research areas of interest. DISCUSSION/SIGNIFICANCE OF IMPACT: The TC demonstrated to be an effective strategy to provide new knowledge, experiences, and interest in CTR. It also established a pathway for future engagement in CTR.
We aimed to quantify the proportion of people receiving care for HIV-infection that are 50 years or older (older HIV patients) in Latin America and the Caribbean between 2000 and 2015 and to estimate the contribution to the growth of this population of people enrolled before (<50yo) and after 50 years old (yo) (⩾50yo). We used a series of repeated, cross-sectional measurements over time in the Caribbean, Central and South American network (CCASAnet) cohort. We estimated the percentage of patients retained in care each year that were older HIV patients. For every calendar year, we divided patients into two groups: those who enrolled before age 50 and after age 50. We used logistic regression models to estimate the change in the proportion of older HIV patients between 2000 and 2015. The percentage of CCASAnet HIV patients over 50 years had a threefold increase (8% to 24%) between 2000 and 2015. Most of the growth of this population can be explained by the increasing proportion of people that enrolled before 50 years and aged in care. These changes will impact needs of care for people living with HIV, due to multiple comorbidities and high risk of disability associated with aging.
The experiment was carried out in the east of Yucatán, in pastures of B. brizantha. It was of three months duration during the end of the rainy season. Four rumen cannulated cows with an average weight of 442 kg were used at all of three stocking rates: Low (2LU/ha), Medium (4LU/ha) and High (6LU/ha), to evaluate the effect of an empty rumen on the rate of biting, which was measured as the time taken to take 20 uninterrupted bites on ten occasions. The measurements were made on two sequential days at 09.00 h, the first under normal conditions, the second with an empty rumen. There was no effect (P<0.050 of rumen emptying on the rate of biting which was 24 bites per minute when the animals were normal, and 25 bites a minute when the rumen was empty. On the other hand, there was a reduction of 8% in the rate of biting for the animals at the high stocking rate compared with the low and medium stocking rates. The finding that bite rate was not affected by an empty the rumen is evidence which gives confidence in the use of cannulated animals as collectors of representative samples of forage under grazing conditions.
The aim of this research is to ameliorate the dispersion of pristine and functionalized Carbon Nanotubes (CNTs) into polystyrene with hydroxyl end groups (PSOH) matrices using low magnetic fields. The Multi-Walled Carbon Nanotubes (MWCNTs) were synthesized by chemical vapor deposition (CVD) using benzene as carbon source; to produce CNTs with and without functional groups two catalysts were used (stainless steel and ferrocene). The obtained nanotubes contained iron nanoparticles inside. PSOH were synthesized using styrene as monomer, azobisisobutyronitrile as initiator and 2-MeOH as chain transfer agent. The MWCNTs-PSOH matrices were formed using 1.6 wt % of carbon nanotubes into PSOH and ultrasonic mixing for 30 min. The mixing materials were poured into containers and dry at room temperature. While the material was drying, constant magnetic fields of 0.24 T were being applied for 50 min. The MWCNTs-PSOH composites were analysed by SEM, FTIR and Raman spectroscopy. SEM micrographs showed that MWCNTs without functional groups were incorporated in the middle of PSOH. The MWCNTs functionalized perform differently; a better dispersion through the entire polymer matrix was achieved, because the polymer embedded the CNTs. FTIR and Raman spectroscopy showed chemical interaction between PSOH and MWCNTs functionalized. The CNTs dispersion into PSOH was ameliorated through the use of low magnetic fields and functionalization.
Childhood obesity has increased rapidly in Mexico, along with changes in the food environment. However, little is known about the dietary patterns (DP) of Mexican children. We aimed to characterize the DP of schoolchildren and to analyse their associations with sociodemographic factors.
Cross-sectional analysis. Dietary and sociodemographic information was obtained, including a single 24 h recall, socio-economic status (SES), geographic region, area of residence and ethnicity. DP were defined with cluster analysis (using k-means). Multinomial logistic regression models, adjusted for the survey design, were used to assess associations between DP and sociodemographic variables.
2012 Mexican National Health and Nutrition Survey (ENSANUT-2012).
Schoolchildren (n 2751) aged 5–11 years who participated in ENSANUT-2012.
Four DP were identified: ‘Traditional’, ‘Industrialized’, ‘Varied’ and ‘Modern’. Reported energy intake (mean (sd)) was lowest in the ‘Traditional’ and highest in the ‘Industrialized’ DP (7037 (3707) kJ/d (1682 (886) kcal/d) v. 8427 (3753) kJ/d (2014 (897) kcal/d), respectively, P<0·05). Significant differences in fat and fibre intakes were seen across DP. Non-indigenous v. indigenous children were 22·0 times (95 % CI 5·1, 93·6) more likely to have a ‘Modern’ rather than ‘Traditional’ DP. Relative likelihood of having an ‘Industrialized’ rather than ‘Traditional’ DP was 6·2 (95 % CI 3·9, 9·9) among schoolchildren from high SES v. low SES.
Among Mexican schoolchildren, DP were associated with sociodemographic variables. Non-indigenous children were significantly more likely to consume a ‘Modern’ than a ‘Traditional’ DP. Children with higher SES were more likely to have an ‘Industrialized’ pattern. It is necessary to consider dietary characteristics in the different sociodemographic strata when dietary interventions are designed.
Forage trees are commonly use for livestock feeding in the tropics. It is known that some species can affect the rumen protozoa population (Odenyo et al., 1997). However, little is known about the potential effect upon rumen protozoa of several species which are also use as feed in tropical systems. The objective of the experiment was to assess the defaunating capacity of forage trees. In companion reports (Monforte et al., 2005) we reported plants with a potential defaunating effect as evaluated under an in vitro batch culture system (Sandoval et al., 2005). Here we present those plants which did not have or had low effect on protozoa population in an in vitro culture.
Rumen protozoa population is reduced when ruminant are feed with foliage from some tropical trees an effect attributed to both saponins (Diaz et al., 1992) and tannins (Odenyo et al., 1997a). As PEG binds to tannins, it has been used to reduce its deleterious effect in animals feed tanniferous trees (Makkar et al., 1998). In a companion summary (Monforte et al., 2005) we showed that using PEG the defaunating capacity of a tanniferous tree is reduced. The objective of the present study was to assess if adding PEG to a protozoa culture will help to separate the tannin and saponin effect upon the protozoa population.
The microbial protein synthesis is variable and depend of several of factors, one the most important being the energy sources. Numerous investigations have evaluated individual sugars. However, few quantitative information is available describing the impact of sucrose or its monosacharides (glucose and fructose) and how they compare with other carbohydrate such as starch (Heldt et al., 1999). Chamberlain and Choung (1995) mention that sugar supplementation results in a higher microbial nitrogen supply (MNS) than starch. On the other hand, the amount of nutrients that ruminants can remove from feeds, may be modified by others feeds eaten the same day (Gill and Powell, 1993). Thus, feeding pattern might also affect microbial-N supply (Chamberlain and Choung, 1995). Therefore, the objective of the present work was to compare maize and sugarcane molasses as energy sources as well as the change of feeding pattern (CFP) on DM intake and MNS.
In Chiapas, México, natural vegetation is often used for grazing cattle. Local knowledge identify several plants and fruits as been consumed by cattle, But few information is available on their nutritive value. The objective of the present work was to assess the potential nutritive value and biological activity of tannins in 14 materials by means of the in vitro gas production technique.
The main goal of this work consisted in cloning, purifying and characterizing a protein phosphatase 2C (PP2C) from promastigotes of Leishmania major. The gene was cloned and amplified by PCR using specific oligonucleotides and the recombinant protein was purified by affinity chromatography. The peak with maximal protein concentration was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and revealed a protein of 44·9 kDa with PP2C activity. This activity was dependent on divalent cations (Mg+2 and Mn+2) and was optimal at pH of 8·5, using phosphothreonine as the substrate. Sanguinarine inhibited the activity of the recombinant LmPP2C, while protein tyrosine phosphatase inhibitors had no effect. The recombinant LmPP2C was used to generate polyclonal antibodies. These antibodies recognized a protein of 44·9 kDa in different Leishmania species; the LmPP2C was localized in the flagellar pocket and the flagellum of promastigotes.