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1.
Soc Psychiatry Psychiatr Epidemiol ; 57(12): 2423-2432, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36048184

RESUMO

OBJECTIVES: To evaluate the association between adverse experiences during Hurricane María and mental and emotional distress in Puerto Rico. METHODS: This cross-sectional study used baseline data from adult (30-75 years) participants of the Puerto Rico Observational Study of Psychosocial, Environmental, and Chronic Disease Trends (PROSPECT). Enrolled individuals prior to COVID-19 who completed a 33-item questionnaire on Hurricane María-related experiences (sub-categorized as personal, service, or property losses), depression symptomatology, post-traumatic stress disorder (PTSD), and anxiety were included for analysis (n = 456). RESULTS: Most participants experienced fear for their family's safety, damage to their home and personal items, communication outages, and water shortages. Each additional stressor was significantly associated with higher odds of depression symptoms, PTSD, and anxiety. Personal losses were significantly associated with higher likelihood of all outcomes, while services losses were associated with depression symptoms and anxiety; property loss was not significantly associated with any outcome. CONCLUSIONS: Adverse experiences during a major natural disaster are associated with mental and emotional distress. Strategies to minimize hardships during natural disasters, especially personal and service losses, are essential to preserve mental health. Post-disaster psychological support to individuals is crucial.


Assuntos
COVID-19 , Tempestades Ciclônicas , Angústia Psicológica , Adulto , Humanos , Porto Rico/epidemiologia , Estudos Transversais , COVID-19/epidemiologia
2.
Am J Epidemiol ; 190(5): 707-717, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33083832

RESUMO

The Puerto Rico Observational Study of Psychosocial, Environmental, and Chronic Disease Trends (PROSPECT) is a prospective cohort study in Puerto Rico (PR) aiming to identify trends and longitudinal associations in risk factors for cardiovascular disease (CVD). In 2019, PROSPECT investigators started recruiting a sample of 2,000 adults aged 30-75 years in PR using multistage probabilistic sampling of households and community approaches. Culturally sensitive trained research assistants assess participants, at baseline and at 2-year follow-up, in private rooms at a network of partner clinics. The study collects comprehensive data on demographic factors, socioeconomic and environmental factors, medical history, health conditions, lifestyle behaviors, psychosocial status, and biomarkers of CVD and stress. PROSPECT will estimate the prevalence and incidence of psychosocial, lifestyle, and biological CVD risk factors, describe variations in risk factors by urbanicity (urban areas vs. rural areas) and exposure (before and after) to natural disasters, and determine predictors of longitudinal changes in CVD risk factors. The study has 4 coordinated operational strategies: 1) research productivity (including synergy with existing epidemiologic cohorts of Hispanics/Latinos for comparison); 2) research infrastructure (biorepository, ancillary studies, and clinical research network); 3) capacity-building, education, and training; and 4) community outreach, dissemination, and policy. PROSPECT will inform public health priorities to help reduce CVD in PR.


Assuntos
Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/epidemiologia , Estudos Epidemiológicos , Fatores de Risco de Doenças Cardíacas , Projetos de Pesquisa , Adulto , Idoso , Doença Crônica , Feminino , Disparidades nos Níveis de Saúde , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Desastres Naturais , Prevalência , Estudos Prospectivos , Porto Rico/epidemiologia , Características de Residência
5.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt B): 3513-3519, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27154287

RESUMO

BACKGROUND: We have studied microscopic dynamics of a protein in carbon disulfide, a non-glass forming solvent, down to its freezing temperature of ca. 160K. METHODS: We have utilized quasielastic neutron scattering. RESULTS: A comparison of lysozyme hydrated with water and dissolved in carbon disulfide reveals a stark difference in the temperature dependence of the protein's microscopic relaxation dynamics induced by the solvent. In the case of hydration water, the common protein glass-forming solvent, the protein relaxation slows down in response to a large increase in the water viscosity on cooling down, exhibiting a well-known protein dynamical transition. The dynamical transition disappears in non-glass forming carbon disulfide, whose viscosity remains a weak function of temperature all the way down to freezing at just below 160K. The microscopic relaxation dynamics of lysozyme dissolved in carbon disulfide is sustained down to the freezing temperature of its solvent at a rate similar to that measured at ambient temperature. CONCLUSIONS: Our results demonstrate that protein dynamical transition is not merely solvent-assisted, but rather solvent-induced, or, more precisely, is a reflection of the temperature dependence of the solvent's glass-forming dynamics. GENERAL SIGNIFICANCE: We hypothesize that, if the long debated idea regarding the direct link between the microscopic relaxations and the biological activity in proteins is correct, then not only the microscopic relaxations, but also the activity, could be sustained in proteins all the way down to the freezing temperature of a non-glass forming solvent with a weak temperature dependence of its viscosity. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.


Assuntos
Vidro/química , Microscopia/métodos , Muramidase/química , Solventes/química , Temperatura , Água/química , Elasticidade , Difração de Nêutrons
8.
Poult Sci ; 95(5): 1077-87, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26908892

RESUMO

An experiment utilizing 960 Ross × Ross 708 male broilers was conducted to determine the effects of Ca feeding strategy on true ileal (prececal) P digestibility (TIPD) and true P retention (TPR) of corn. Experimental diets were formulated with 1 of 3 dietary Ca feeding strategies (0.95%, 0.13%, or variable Ca concentrations to maintain a 2.1:1 Ca:P ratio) and contain 0, 25, 50, or 75% corn. A practical corn-soybean meal diet (1.4:1 Ca:P ratio) was fed as a control. After receiving a common starter diet, experimental diets were fed from 19 to 26 d of age. After a 48-h dietary adaptation period, a 48-h retention assay was conducted. At 25 and 26 d of age, ileal digesta were collected from 8 birds per cage. Broilers consuming the control diet had higher (P<0.001) BW gain, feed intake, digesta P, and excreta P than broilers consuming the corn titration diets. Digesta and excreta P increased (linear, P<0.05) with graded increases of corn. True ileal P digestibility and TPR were highest (P<0.05) for diets with 0.13% Ca (57.3 and 69.5%, respectively) compared with diets formulated with a 2.1:1 Ca:P ratio (41.2 and 37.8%, respectively) or 0.95% Ca (25.4 and 39.0%, respectively). Values for TPR were higher (P<0.05) than those for TIPD except when the dietary Ca:P ratio was fixed. Additionally, negative endogenous P losses were predicted by regression equations when TPR was estimated for birds fed titration diets with the fixed Ca:P ratio. Changing the Ca concentration of the diets to maintain a fixed Ca:P ratio influenced (P<0.001) apparent P retention, which affected the estimate for TPR due to the prediction of negative endogenous P losses. These data demonstrated that regression analysis may have limitations when estimating the TIPD or TPR of corn when formulating diets with different Ca feeding strategies. More research is necessary to elucidate the factors that contributed to regression equations predicting negative endogenous P losses.


Assuntos
Cálcio/farmacologia , Galinhas/crescimento & desenvolvimento , Digestão/fisiologia , Íleo/fisiologia , Fósforo/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cálcio/administração & dosagem , Cálcio/metabolismo , Dieta/veterinária , Relação Dose-Resposta a Droga , Masculino
9.
Soft Matter ; 11(34): 6755-67, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26212615

RESUMO

Antimicrobial peptides are universal in all forms of life and are well known for their strong interaction with the cell membrane. This makes them a popular target for investigation of peptide-lipid interactions. Here we report the effect of melittin, an important antimicrobial peptide, on the dynamics of membranes based on 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipid in both the solid gel and fluid phases. To probe the phase transition, elastic neutron intensity temperature scans have been carried out on DMPC-based unilamellar vesicles (ULV) with and without melittin. We have found that addition of a small amount (0.2 mol%) melittin eliminates the steep fall in the elastic intensity at 296 K associated with the solid gel to fluid phase transition, which is observed for pure DMPC vesicles. Quasielastic neutron scattering (QENS) experiments have been carried out on DMPC ULV in the solid gel and fluid phases with and without 0.2 mol% melittin. The data analysis invariably shows the presence of lateral and internal motions of the DMPC molecule. We found that melittin does have a profound effect on the dynamics of lipid molecules, especially on the lateral motion, and affects it in a different way, depending on the phase of the bilayers. In the solid gel phase, it acts as a plasticizer, enhancing the lateral motion of DMPC. However, in the fluid phase it acts as a stiffening agent, restricting the lateral motion of the lipid molecules. These observations are consistent with the mean squared displacements extracted from the elastic intensity temperature scans. Their importance lies in the fact that many membrane processes, including signaling and energy transduction pathways, are controlled to a great extent by the lateral diffusion of lipids in the membrane. To investigate the effect of melittin on vesicles supplemented with cholesterol, QENS experiments have also been carried out on DMPC ULV with cholesterol in the presence and absence of 0.2 mol% melittin. Remarkably, the effects of melittin on the membrane dynamics disappear in the presence of 20 mol% cholesterol. Our measurements indicate that the destabilizing effect of the peptide melittin on membranes can be mitigated by the presence of cholesterol. This study might provide new insights into the mechanism of action of antimicrobial peptides and their selective toxicity towards foreign microorganisms.


Assuntos
Membrana Celular/efeitos dos fármacos , Colesterol/metabolismo , Dimiristoilfosfatidilcolina/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Meliteno/farmacologia , Membrana Celular/química , Membrana Celular/metabolismo , Meliteno/metabolismo , Temperatura , Lipossomas Unilamelares/química , Lipossomas Unilamelares/metabolismo
10.
Poult Sci ; 93(5): 1178-85, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24795310

RESUMO

As distillers dried grains with solubles (DDGS) become increasingly available, it is important to determine their nutritional value for precise feed formulation. The accurate determination of digestibility is crucial, and it is known that the methods used will affect the values obtained. An experiment was designed to determine and compare the standardized ileal digestibility (SID) of amino acids from wheat DDGS using a semisynthetic diet and a difference method using 4 further diets based on corn, wheat, corn DDGS, and wheat DDGS. Eighty 1-d-old male broilers were fed a commercial starter diet until d 21. Between d 21 and 23, they were fed test diets in order to adapt to those diets before the trial took place between d 24 and 27. The trial period took place between d 24 and 27. Feed intake was measured, excreta collected, and at d 27, all birds were culled and ileal digesta was collected for the determination of apparent ileal digestibility and SID of amino acids. Values determined were similar to those reported elsewhere in the literature, although SID values for lysine were particularly low, being 0.26, 0.27, or 0.32, measured in semisynthetic, corn, or wheat diet backgrounds, respectively. It appeared that diet type employed was influential in the values obtained. The SID values for methionine, cysteine, methionine plus cysteine, and arginine were significantly lower (P < 0.05) when measured in semisynthetic diet backgrounds than wheat- or corn-based diets. It appears that dextrose and possibly purified starch have a detrimental impact on the broiler digestive tract. This may affect all digestibility methodologies in which such a diet base is used.


Assuntos
Aminoácidos/metabolismo , Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Digestão , Íleo/metabolismo , Triticum/química , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Masculino , Valor Nutritivo , Triticum/metabolismo
11.
J Biol Phys ; 40(2): 167-78, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24664796

RESUMO

The effects of a static electric field on the dynamics of lysozyme and its hydration water are investigated by means of incoherent quasi-elastic neutron scattering (QENS). Measurements were performed on lysozyme samples, hydrated respectively with heavy water (D2O) to capture the protein dynamics and with light water (H2O), to probe the dynamics of the hydration shell, in the temperature range from 210 < T < 260 K. The hydration fraction in both cases was about ∼ 0.38 gram of water per gram of dry protein. The field strengths investigated were respectively 0 kV/mm and 2 kV/mm (~2 × 10(6) V/m) for the protein hydrated with D2O and 0 kV and 1 kV/mm for the H2O-hydrated counterpart. While the overall internal protons dynamics of the protein appears to be unaffected by the application of an electric field up to 2 kV/mm, likely due to the stronger intra-molecular interactions, there is also no appreciable quantitative enhancement of the diffusive dynamics of the hydration water, as would be anticipated based on our recent observations in water confined in silica pores under field values of 2.5 kV/mm. This may be due to the difference in surface interactions between water and the two adsorption hosts (silica and protein), or to the existence of a critical threshold field value Ec ~2-3 kV/mm for increased molecular diffusion, for which electrical breakdown is a limitation for our sample.


Assuntos
Óxido de Deutério/química , Eletricidade , Muramidase/química , Muramidase/metabolismo , Difração de Nêutrons , Temperatura
12.
Br Poult Sci ; 55(3): 351-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24579789

RESUMO

1. A previous experiment reported that caecal temperature was negatively correlated with d 49 feed conversion ratio (FCR). This increased temperature in the caeca may indicate a prebiotic effect. An experiment was designed to investigate whether caecal temperature was affected in diets based on maize and whether other portions of the tract were affected. 2. A total of 25 Ross 308-d-old male broilers were allocated to each of 8 replicate pens per treatment. Treatments followed a 2 × 3 factorial design: two diets based on wheat or maize and three levels of enzyme addition, 0, 16 000 or 32 000 BXU/kg. Growth performance was assessed between d 1 and 49. Digestibility measurements were taken at d 28 and 49. On d 49, the excised small and large intestine of each bird was thermally imaged, weighed and volatile fatty acids (VFA) measured. 3. On d 28 and d 49, birds on the maize diets had higher feed intake and weight gain than those offered wheat diets. Additionally, on d 28, birds that received the maize diet had lower FCR than those offered the wheat diet. Enzyme improved FCR at d 49, independently of cereal. On d 28, enzyme improved the coefficient of apparent ileal DM digestibility and the coefficient of apparent ileal nitrogen digestibility. Enzyme only improved apparent ileal digestible energy in wheat-based diets (interactive term). On d 49, all digestibility parameters were improved by enzyme. Enzyme increased gizzard weight in maize-fed birds and the caeca of those fed wheat were heavier. The higher enzyme dose decreased duodenal temperature. In summary of VFA data, wheat-based diets produced more total VFAs and the total amount also increased with enzyme. 4. It appears from this study that there is equal potential in both wheat and maize diets for xylanase to improve performance of broilers probably through different mechanisms.


Assuntos
Ração Animal , Galinhas/crescimento & desenvolvimento , Digestão/efeitos dos fármacos , Endo-1,4-beta-Xilanases/farmacologia , Ácidos Graxos Voláteis/biossíntese , Triticum , Zea mays , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Peso Corporal , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/fisiologia , Masculino , Nitrogênio/metabolismo
13.
Asian-Australas J Anim Sci ; 27(2): 290-301, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25049954

RESUMO

The first purpose of this review is to outline some of the background information necessary to understand the mechanisms of action of fibre-degrading enzymes in non-ruminants. Secondly, the well-known and understood mechanisms are described, i) eliminating the nutrient encapsulating effect of the cell wall and ii) ameliorating viscosity problems associated with certain Non Starch Polysaccharides, particularly arabinoxylans and ß-glucans. A third, indirect mechanism is then discussed: the activity of such enzymes in producing prebiotic oligosaccharides and promoting beneficial cecal fermentation. The literature contains a wealth of information on various non starch polysaccharide degrading enzyme (NSPase) preparations and this review aims to conclude by discussing this body of work, with reference to the above mechanisms. It is suggested that the way in which multi- versus single-component products are compared is often flawed and that some continuity should be employed in methods and terminology.

14.
Nature ; 447(7142): 303-6, 2007 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-17507980

RESUMO

The chemical composition of basaltic magma erupted at the Earth's surface is the end product of a complex series of processes, beginning with partial melting and melt extraction from a mantle source and ending with fractional crystallization and crustal assimilation at lower pressures. It has been proposed that studying inclusions of melt trapped in early crystallizing phenocrysts such as Mg-rich olivine and chromite may help petrologists to see beyond the later-stage processes and back to the origin of the partial melts in the mantle. Melt inclusion suites often span a much greater compositional range than associated erupted lavas, and a significant minority of inclusions carry distinct compositions that have been claimed to sample melts from earlier stages of melt production, preserving separate contributions from mantle heterogeneities. This hypothesis is underpinned by the assumption that melt inclusions, once trapped, remain chemically isolated from the external magma for all elements except those that are compatible in the host minerals. Here we show that the fluxes of rare-earth elements through olivine and chromite by lattice diffusion are sufficiently rapid at magmatic temperatures to re-equilibrate completely the rare-earth-element patterns of trapped melt inclusions in times that are short compared to those estimated for the production and ascent of mantle-derived magma or for magma residence in the crust. Phenocryst-hosted melt inclusions with anomalous trace-element signatures must therefore form shortly before magma eruption and cooling. We conclude that the assumption of chemical isolation of incompatible elements in olivine- and chromite-hosted melt inclusions is not valid, and we call for re-evaluation of the popular interpretation that anomalous melt inclusions represent preserved samples of unmodified mantle melts.

15.
Br Poult Sci ; 54(3): 346-54, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23650997

RESUMO

1. Five dietary treatments were used in a 49 d broiler trial to assess the effect of xylanase on performance, nutrient digestibility and thermal profiles of the caeca and head. Treatments included an industry-standard control diet and four further diets where xylanase was introduced with or without a metabolisable energy density dilution either from day one or the introduction was delayed until d 28. 2. The addition of xylanase with no associated energy dilution from day one resulted in the most consistent beneficial effects on performance, with significant improvements in weight gain compared with the industry-standard to d 28 and at d 49. Addition of xylanase from d 28 (with no energy dilution) was the second most successful strategy and resulted in a significant improvement in feed conversion ratio (FCR) from d 29 to 49 and overall. 3. Addition of xylanase improved ileal digestible energy values at d 28 by around 0.35 MJ/kg and ileal nitrogen digestibility coefficients by around 3%. On d 49 xylanase improved ileal digestible energy values by around 0.9 MJ/kg and ileal nitrogen digestibility coefficients by around 4.6%. 4. Thermal imaging of the head and caeca of three birds per replicate on d 49 revealed a significant increase in caecal surface temperature following xylanase addition with no effect on head temperature profile. These increases were particularly large (around 1.4ºC, or 3.9%) when xylanase was added from day one with no corresponding energy dilution in feed formulation. 5. It can be concluded that supplemental xylanase is effective in improving performance and nutrient digestibility in broilers given wheat-based diets. The correlation between the magnitude of this effect and the increased temperature in the caeca presents additional evidence that the hind-gut microflora may play an important, if yet unquantified, role in the outworking of these mechanisms.


Assuntos
Ceco/fisiologia , Galinhas/fisiologia , Dieta/veterinária , Digestão/efeitos dos fármacos , Endo-1,4-beta-Xilanases/administração & dosagem , Triticum , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ceco/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Íleo/efeitos dos fármacos , Íleo/metabolismo , Masculino , Nitrogênio/metabolismo , Glycine max , Aumento de Peso
16.
J Nutr Educ Behav ; 55(9): 644-650, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37395692

RESUMO

OBJECTIVE: To examine the association between food insecurity and dysfunctional eating behaviors among adults in Puerto Rico. METHODS: Data from 865 participants were obtained from baseline interviews from the Puerto Rico Observational Study of Psychosocial, Environmental, and Chronic Disease Trends (PROSPECT) cohort. The association between food insecurity and emotional eating (EE) and uncontrolled eating (UE) (categorized as no/moderate/high) was examined using multinomial logistic models. Potential mediation by perceived stress was explored. RESULTS: The prevalence of food insecurity was 20.3%. Compared with adults with food security, adults with food insecurity had higher odds of both moderate EE (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.18-3.09) and high EE (OR, 2.85; 95% CI, 1.75-4.64), and both moderate UE (OR, 1.78; 95% CI, 0.91-3.50) and high UE (OR, 3.28; 95% CI, 1.70-6.33). Perceived stress slightly attenuated these associations. CONCLUSIONS AND IMPLICATIONS: Food insecurity was associated with a higher likelihood of engaging in dysfunctional eating behaviors. Interventions alleviating food insecurity or stress might help adults sustain healthy eating behaviors.


Assuntos
Comportamento Alimentar , Abastecimento de Alimentos , Humanos , Adulto , Porto Rico/epidemiologia , Emoções , Insegurança Alimentar
17.
Front Public Health ; 11: 1269390, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38445250

RESUMO

Objectives: To report the adaptation and implementation of LUCHA (Latinos United for a Culturally Healthy Alimentation), a pilot intervention to improve dietary quality and behaviors (primary outcomes) of Latinos in Massachusetts, US, and the lessons learned during the process, including disruptions during the COVID-19 pandemic, to help shape future programs. Methods: The cultural adaptation process was pre-planned using a framework, grounded in the Theory of Reasoned Action/Planned Behavior, and informed by formative mixed-methods research. A projected 75 self-identifying Latino adults (25-65y) were recruited with community-wide strategies and randomized to receive, in parallel, daily healthy eating text messages for 2 months, reinforced for 2 subsequent months, to either control (i.e., surface-level messages based on USDA MyPlate in Spanish), or intervention (i.e., deep-structure messages). The intervention messages were ethnically tailored to Caribbean or non-Caribbean heritages specifically, grounded in entrenched cultural attitudes, norms, and preferences. Trained research assistants administered questionnaires and clinical measurements at baseline, 2-months, and 4-months, in person (pre-pandemic) or via online video calls (at-pandemic). Clinicaltrials.gov registration #NCT04724382. Results: LUCHA faced challenges and opportunities that conveyed lessons for future cultural adaptation and implementation of healthy eating programs. Recommendations are provided to improve digital programs for diverse ethnicities, such as widening language capabilities in texting services, using familiar video call applications, and instructing participants to measure their own clinical metrics at home using guided standardized protocols. Conclusion: Tailoring nutrition programs with deep-structure cultural messages is essential when promoting healthy eating in diverse Latino heritages. LUCHA can inform programs for similar ethnic groups.


Assuntos
Dieta Saudável , Pandemias , Humanos , Etnicidade , Hispânico ou Latino , Projetos Piloto , Adulto , Pessoa de Meia-Idade , Idoso , População do Caribe
18.
Sci Total Environ ; 870: 161867, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36716885

RESUMO

Microplastics (MPs) and nanoplastics (NPs) from mulch films and other plastic materials employed in vegetable and small fruit production pose a major threat to agricultural ecosystems. For conducting controlled studies on MPs' and NPs' (MNPs') ecotoxicity to soil organisms and plants and fate and transport in soil, surrogate MNPs are required that mimic MNPs that form in agricultural fields. We have developed a procedure to prepare MPs from plastic films or pellets using mechanical milling and sieving, and conversion of the resultant MPs into NPs through wet grinding, both steps of which mimic the degradation and fragmentation of plastics in nature. The major goal of this study was to determine if cryogenic exposure of two biodegradable mulch films effectively mimics the embrittlement caused by environmental weathering in terms of the dimensional, thermal, chemical, and biodegradability properties of the formed MNPs. We found differences in size, surface charge, thermal and chemical properties, and biodegradability in soil between MNPs prepared from cryogenically treated vs. environmentally weathered films, related to the photochemical reactions occurring in the environment that were not mimicked by cryogenic treatment, such as depolymerization and cross-link formation. We also investigated the size reduction process for NPs and found that the size distribution was bimodal, with populations centered at 50 nm and 150-300 nm, and as the size reduction process progressed, the former subpopulation's proportion increased. The biodegradability of MPs in soil was greater than for NPs, a counter-intuitive trend since greater surface area exposure for NPs would increase biodegradability. The result isassociated with differences in surface and chemical properties and to minor components that are readily leached out during the formation of NPs. In summary, the use of weathered plastics as feedstock would likely produce MNPs that are more realistic than cryogenically-treated unweathered films for use in experimental studies.

19.
Poult Sci ; 102(12): 103113, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37856910

RESUMO

The present study was conducted to investigate the stimbiotic mechanism of xylo-oligosaccharide (XOS) in degrading the complex polysaccharides by the caecal bacteria of the chicken, by applying a proteomic approach. A total of 800 as-hatched Ross 308 broiler chicks were equally divided into 4 experimental pens (200 chicks per pen) at a commercial poultry barn, allocating 2 pens per treatment. Birds were fed ad libitum with 2 dietary treatments; CON (without XOS) and XOS (with 0.1g XOS/kg diet) from d 0 to 35. From each pen, 60 Individual birds were weighed weekly whereas caecal content was obtained from 5 birds cervically dislocated on d 35. The caecal bacteria were lysed and their proteins were quantified using label-free quantitative proteomic mass spectrometry. The results showed that XOS significantly increased (P < 0.05) bird weight on d 7, 14, 21, and 28, and body weight gain on d 7, 14, 21, and 35 compared to CON. However, no difference (P > 0.05) in body weight gain was observed from d 0 to 35 between CON and XOS. The proteomic analysis of caecal bacteria revealed that 29 proteins were expressed differently between the CON and the XOS group. Out of 29, 20 proteins were significantly increased in the XOS group compared to CON and 9 of those proteins belonged to the starch-utilizing system (Sus)-like system of the gram-negative Bacteroidetes. Bacteroides thetaiotaomicron (Bt) is a significant constituent of the human gut microbiota, known for its remarkable ability to hydrolyze most glycosidic bonds of polysaccharides. This microorganism possesses a 5-protein complex in its outer membrane, named the starch utilization system (Sus), responsible for adhering to, breaking down, and transporting starch into the cell. Sus serves as an exemplar system for numerous polysaccharide utilization loci that target glycans found in Bt and other members of the Bacteroidetes phylum. The proteins of the Sus-like system are involved in the degradation of complex polysaccharides and transportation of the oligosaccharides into the periplasm of the caecal bacteria where they are further broken down into smaller units. These smaller units are then transported into the cytoplasm of the cell where they are utilized in metabolic pathways leading to potential generation of short-chain fatty acids, thus improving the nutritive value of residual feed. In conclusion, XOS supplementation upregulates the expression of the proteins of the Sus-like system indicating its role as a stimbiotic.


Assuntos
Galinhas , Prebióticos , Animais , Humanos , Galinhas/metabolismo , Bacteroidetes , Proteômica , Oligossacarídeos/metabolismo , Bactérias/metabolismo , Amido/metabolismo , Peso Corporal
20.
Ethn Dis ; 33(4): 140-149, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38854413

RESUMO

Introduction: Latinos report lower self-rated health (SRH) than non-Hispanic White persons. However, the association between SRH and medically diagnosed chronic diseases (MDCDs) remains understudied in Latino populations. This study assessed the relationship between a single-item SRH indicator and MDCD status among predominantly Latino adults in Puerto Rico. Methods: Participants (30-75 years; n=965) of the Puerto Rico Observational Study of Psychosocial, Environmental, and Chronic Disease Trends (PROSPECT) reported SRH (excellent/very good, good, or fair/poor) and MDCD (ever vs never). We performed multivariate logistic regressions to evaluate the association between SRH and MDCD, which adjusted for key socioeconomic, demographic, and behavioral confounders. Results: Twenty-seven percent of participants reported excellent/very good SRH, 39% good, and 34% fair/poor. Participants with fair/poor SRH (vs excellent/very good) were more likely to report MDCD for painful inflammation (odds ratio [OR]=4.95 [95% CI, 3.27-7.48]), kidney disease (4.64 [2.16-9.97]), sleep disorder (4.47 [2.83-7.05]), migraine headaches (4.07 [2.52-6.58]), overweight/obesity (3.84 [2.51-5.88]), depression (3.61 [2.28-5.74]), hypertension (3.59 [2.43-5.32]), high blood sugar (3.43 [2.00-5.89]), cardiovascular disease (3.13 [2.01-4.87]), anxiety (2.87 [1.85-4.44]), arthritis (2.80 [1.83-4.30]), diabetes (2.46 [1.57-3.83]), respiratory problems (2.45 [1.59-3.79]), stomach problems (2.44 [1.57-3.81]), eye disease (2.42 [1.44-4.06]), gallbladder disease (2.34 [1.35-4.05]), liver disease (2.26 [1.38-3.70]), heartburn (2.25 [1.55-3.26]), hyperlipidemia (2.10 [1.44-3.06]), and thyroid conditions (2.04 [1.30-3.21]). Conclusions: SRH may reflect MDCD burden and serve as a valid screener to efficiently identify Latino individuals in high need of clinical services. This is relevant in Puerto Rico, where chronic disease rates remain high amid limited, disparate access to health care.


Assuntos
Nível de Saúde , Humanos , Porto Rico/epidemiologia , Porto Rico/etnologia , Pessoa de Meia-Idade , Masculino , Feminino , Adulto , Idoso , Doença Crônica , Autorrelato , Hispânico ou Latino/estatística & dados numéricos
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