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SUMMARY: Once folded, natural protein molecules have few energetic conflicts within their polypeptide chains. Many protein structures do however contain regions where energetic conflicts remain after folding, i.e. they are highly frustrated. These regions, kept in place over evolutionary and physiological timescales, are related to several functional aspects of natural proteins such as protein-protein interactions, small ligand recognition, catalytic sites and allostery. Here, we present FrustratometeR, an R package that easily computes local energetic frustration on a personal computer or a cluster. This package facilitates large scale analysis of local frustration, point mutants and molecular dynamics (MD) trajectories, allowing straightforward integration of local frustration analysis into pipelines for protein structural analysis. AVAILABILITY AND IMPLEMENTATION: https://github.com/proteinphysiologylab/frustratometeR. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Simulação de Dinâmica Molecular , Proteínas , Domínio Catalítico , SoftwareRESUMO
OBJECTIVE: The objective of the study was to measure the proportion of patients who consulted for headache and of those who had a final diagnosis of migraine. We also assessed the proportion and characteristics of patients with migraine and the impact of migraine on the daily activities and the professional and social lives of patients visiting private/public medical centers in Guatemala, Costa Rica, Panama, and the Dominican Republic. BACKGROUND: Underdiagnosis of migraine is high in Central America and Caribbean urban communities. However, there is limited knowledge on characteristics of headache disorders for the appropriate classification of migraine, which is a prerequisite for targeted treatment. Hence, there is a need to improve migraine awareness among patients and medical professionals in this region. METHODS: Central America and Caribbean countries epidemioLogy study of Migraine (CALM) was a non-interventional, cross-sectional, multinational study in adults aged 18-65 years with a history of or current headache. The primary outcome was the proportion of patients with migraine visiting medical centers due to headache disorders. Using a specially designed migraine survey questionnaire, patients self-reported migraine characteristics, duration, and severity of attacks and impact on work and social life. RESULTS: Of the 313 enrolled patients, 308 (98.4%) completed the study. Approximately 75.3% (232/308) of patients with headache visiting medical centers had migraine, with episodic migraine being the most common (193 [83.2%]). Overall, 34/308 (11.0%) patients had a new diagnosis of migraine. Among patients with migraine, 66 (28.4%) had a history of migraine for ≥20 years and 59 (25.4%) experienced severe pain. Overall, 52.2% (121/232) of patients reported that migraine affected their professional life and 78.4% (182/232) reported an impact on social life. CONCLUSION: The CALM study establishes that a high proportion of patients with migraine had a long duration and high severity of migraine attacks, leading to a direct impact on work/social life as well as on costs incurred by patients in these countries.
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Transtornos de Enxaqueca , Adulto , Custos e Análise de Custo , Estudos Transversais , Cefaleia/epidemiologia , Humanos , Transtornos de Enxaqueca/terapia , Inquéritos e QuestionáriosRESUMO
Human immunodeficiency virus (HIV) infection has continued to be the subject of study since its discovery nearly 40 years ago. Significant advances in research and intake of antiretroviral therapy (ART) have slowed the progression and appearance of the disease symptoms and the incidence of concomitant diseases, which are the leading cause of death in HIV+ persons. However, the prolongation of ART is closely related to chronic degenerative diseases and pathologies caused by oxidative stress (OS) and alterations in lipid metabolism (increased cholesterol levels), both of which are conditions of ART. Therefore, recent research focuses on using natural therapies to diminish the effects of ART and HIV infection: regulating lipid metabolism and reducing OS status. The present review summarizes current information on OS and cholesterol metabolism in HIV+ persons and how the consumption of certain phytochemicals can modulate these. For this purpose, MEDLINE and SCOPUS databases were consulted to identify publications investigating HIV disease and natural therapies and their associated effects.
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Infecções por HIV , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Colesterol , Expressão Gênica , Infecções por HIV/complicações , Humanos , Metabolismo dos Lipídeos , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêuticoRESUMO
The present paper investigates the feasibility of using acetone (ACE) in triple blends with fossil diesel (D) and straight vegetable oils (SVOs) as alternative fuel for diesel engines. In this respect, ACE is selected as an oxygenated additivedue to its favorable propertiesto be mixed with vegetable oils and fossil diesel. In fact, the very low kinematic viscosity allows reduces the high viscosity of SVOs. ACE's oxygen content, low autoignition temperature, and very low cloud point and pour point values highlight its possibilities as an additive in D/ACE/SVO triple blends. Moreover, ACE can be produced through a renewable biotechnological process, an acetone-butanol-ethanol (ABE) fermentation from cellulosic biomass. The SVOs tested were castor oil (CO), which is not suitable for human consumption, and sunflower oil (SO), used as a standard reference for waste cooking oil. The viscosity measurement of the ACE/SVO double blend was considered crucial to choose the optimum proportion, which better fulfilled the specifications established by European standard EN 590. Moreover, some of the most significant physicochemical properties of D/ACE/SVO triple blends, such as kinematic viscosity, cloud point, pour point, and calorific value, were determined to assess their suitability as fuels. The blends were evaluated in a conventional diesel generator through the study of the following parameters: engine power, smoke emissions, and fuel consumption. Despite the low calorific value of ACE limits its ratio in the mixtures due to engine knocking problems, the experimental results reveal an excellent performance for the blends containing up to 16-18% of ACE and 22-24% of SVO. These blends produce similar engine power as to fossil diesel, but with slightly higher fuel consumption. Considerable reductions in emissions of air pollutants, as well as excellent cold flow properties are also obtained with these triple blends. In summary, the use of these biofuels could achieve a substitution of fossil diesel up to 40%, independently on the SVO employed.
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Acetona/química , Biocombustíveis/análise , Óleo de Rícino/química , Gasolina/análise , Óleos de Plantas/química , Óleo de Girassol/química , Emissões de Veículos/análise , HumanosRESUMO
Previous studies demonstrated that pomegranate, which is a source of several bioactive molecules, induces modifications of high-density lipoproteins (HDL) lipid composition and functionality. However, it remains unclear whether the beneficial effects of pomegranate are related to improvement in the lipid components of HDL. Therefore, in this placebo-controlled study, we characterized the size and lipid composition of HDL subclasses and assessed the functionality of these lipoproteins after 30 days of supplementation with a pomegranate microencapsulated (MiPo) in New Zealand white rabbits. We observed a significant decrease in plasma cholesterol, triglycerides, and non-HDL sphingomyelin, as well as increases in HDL cholesterol and HDL phospholipids after supplementation with MiPo. Concomitantly, the triglycerides of the five HDL subclasses isolated by electrophoresis significantly decreased, whereas phospholipids, cholesterol, and sphingomyelin of HDL subclasses, as well as the HDL size distribution remained unchanged. Of particular interest, the triglycerides content of HDL, estimated by the triglycerides-to-phospholipids ratio, decreased significantly after MiPo supplementation. The modification on the lipid content after the supplementation was associated with an increased resistance of HDL to oxidation as determined by the conjugated dienes formation catalyzed by Cu2+. Accordingly, paraoxonase-1 (PON1) activity determined with phenylacetate as substrate increased after MiPo. The effect of HDL on endothelial function was analyzed by the response to increasing doses of acetylcholine of aorta rings co-incubated with the lipoproteins in an isolated organ bath. The HDL from rabbits that received placebo partially inhibited the endothelium-dependent vasodilation. In contrast, the negative effect of HDL on endothelial function was reverted by MiPo supplementation. These results show that the beneficial effects of pomegranate are mediated at least in part by improving the functionality of HDL, probably via the reduction of the content of triglycerides in these lipoproteins.
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Cardiotônicos/química , Frutas/química , Lipoproteínas HDL/metabolismo , Extratos Vegetais/química , Punica granatum/química , Animais , Arildialquilfosfatase/metabolismo , Cardiotônicos/farmacologia , Colesterol/metabolismo , Cobre/metabolismo , Portadores de Fármacos/química , Endotélio/metabolismo , Frutas/metabolismo , Glucose/química , Humanos , Masculino , Fosfolipídeos/metabolismo , Extratos Vegetais/farmacologia , Polissacarídeos/química , Punica granatum/metabolismo , Coelhos , Triglicerídeos/metabolismo , Vasodilatação/efeitos dos fármacosRESUMO
High-density lipoproteins (HDL) comprise a heterogeneous family of lipoprotein particles divided into subclasses that are determined by density, size and surface charge as well as protein composition. Epidemiological studies have suggested an inverse correlation between High-density lipoprotein-cholesterol (HDL-C) levels and the risk of cardiovascular diseases and atherosclerosis. HDLs promote reverse cholesterol transport (RCT) and have several atheroprotective functions such as anti-inflammation, anti-thrombosis, and anti-oxidation. HDLs are considered to be atheroprotective because they are associated in serum with paraoxonases (PONs) which protect HDL from oxidation. Polyphenol consumption reduces the risk of chronic diseases in humans. Polyphenols increase the binding of HDL to PON1, increasing the catalytic activity of PON1. This review summarizes the evidence currently available regarding pharmacological and alternative treatments aimed at improving the functionality of HDL-C. Information on the effectiveness of the treatments has contributed to the understanding of the molecular mechanisms that regulate plasma levels of HDL-C, thereby promoting the development of more effective treatment of cardiovascular diseases. For that purpose, Scopus and Medline databases were searched to identify the publications investigating the impact of current therapies focused on high-density lipoproteins.
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Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Hipolipemiantes/uso terapêutico , Lipoproteínas HDL/metabolismo , Animais , Biomarcadores , Doenças Cardiovasculares/etiologia , HDL-Colesterol/sangue , HDL-Colesterol/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipolipemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas/classificação , Lipoproteínas/metabolismo , Lipoproteínas HDL/sangue , Oxirredução/efeitos dos fármacosRESUMO
The etherification of glycerol with tert-butyl alcohol in the liquid phase, over different sulfonic acid functionalized zeolites, has been studied. The reaction was carried out using microwaves as a way of heating, measured at autogenous pressure and without any solvent. Dealuminated HY and HZSM-5 zeolites by acid treatment were functionalized with two different organosilica precursors: 3-mercaptopropyltrimethoxysilane (M), which incorporates thiol groups, and 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane (C), which incorporates the sulfonic acid groups directly. The thiol groups were oxidized into sulfonic groups employing hydrogen peroxide. The textural and structural properties of the solids were studied by XRD and N2 adsorption-desorption isotherms, whereas the incorporation of the organosilica in the zeolites was studied by TGA and XPS. The novelty functionalization of M gave rise to solids with the highest acidity, and exhibited the highest yields with more substituted ethers (Yh-GTBE = 13%), at 75 °C and 15 min of reaction time. In addition to the acidity, the textural properties of the zeolites played an important role in their activity; HY, with the largest size of the channels, were more active than the HZSM-5.
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Éteres/síntese química , Glicerol/química , Ácidos Sulfônicos/química , Zeolitas/química , terc-Butil Álcool/química , Catálise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Peróxido de Hidrogênio/química , Micro-Ondas , Nitrogênio/químicaRESUMO
The application of biocatalysts in the transesterification process of triglycerides (TG) allows integrating the glycerol in the form of monoglyceride (MG), sharply increasing the yield and the environmental sustainability of the conventional biodiesel production process. This is known as Ecodiesel. To overcome the inconvenient of the high cost of the currently employed highly purified commercial enzymes, the use of scarcely purified extracts obtained from standard strains of the same species of commercial lipases currently applied in this process is being investigated. Thus, Candidaantarctica type B (CALB) was chosen to determine the optimal conditions of culture of this yeast. The standard strain was obtained from the Spanish Type Microbial Cultures Collection (CECT) and has been used to carry out several studies to elucidate its optimum growth conditions. Through a process of lyophilization with prior dialysis of the liquid cultures, the enzymatic extracts were obtained. The different obtained cultures have been applied as biocatalysts in the 1,3-selective transesterification reaction of sunflower oil with ethanol to obtain Ecodiesel (FAEE + MG). Selectivity and reaction yields were obtained by gas chromatography. Acceptable yields are obtained during the reaction time as well as in successive reactions, demonstrating the feasibility of using these CALB enzymatic extracts as biocatalysts.
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Biocombustíveis , Candida/enzimologia , Proteínas Fúngicas/química , Catálise , Ativação Enzimática , Esterificação , Lipase/químicaRESUMO
The effectiveness of conservation interventions for maximizing biodiversity benefits from agri-environment schemes (AESs) is expected to depend on the quantity of seminatural habitats in the surrounding landscape. To verify this hypothesis, we developed a hierarchical sampling design to assess the effects of field boundary type and cover of seminatural habitats in the landscape at two nested spatial scales. We sampled three types of field boundaries with increasing structural complexity (grass margin, simple hedgerow, complex hedgerow) in paired landscapes with the presence or absence of seminatural habitats (radius 0.5 km), that in turn, were nested within 15 areas with different proportions of seminatural habitats at a larger spatial scale (10 X 10 km). Overall, 90 field boundaries were sampled across a Mediterranean'region (northeastern Italy). We considered species richness response across three different taxonomic groups: vascular plants, butterflies, and tachinid flies. No interactions between type of field boundary and surrounding landscape were found at either 0.5 and 10 km, indicating that the quality of field boundary had the same effect irrespective of the cover of seminatural habitats. At the local scale, extended-width grass margins yielded higher plant species richness, while hedgerows yielded higher species richness of butterflies and tachinids. At the 0.5-km landscape scale, the effect of the proportion of seminatural habitats was neutral for plants and tachinids, while butterflies were positively related to the proportion of forest. At the 10-km landscape scale, only butterflies responded positively to the proportion of seminatural habitats. Our study confirmed the importance of testing multiple scales when considering species from different taxa and with different mobility. We showed that the quality of field boundaries at the local scale was an important factor in enhancing farmland biodiversity. For butterflies, AESs should focus particular attention on preservation'of forest patches in agricultural landscapes within 0.5 kin, as well as the conservation of seminatural habitats at a wider landscape scale.
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Agricultura , Biodiversidade , Borboletas/classificação , Dípteros/classificação , Modelos Biológicos , Plantas/classificação , Animais , Monitoramento Ambiental , Florestas , ItáliaRESUMO
A new biofuel similar to biodiesel was obtained in the 1,3-selective transesterification reaction of sunflower oil with ethanol using as biocatalyst a Rhizopus oryzae lipase (ROL) immobilized on Sepiolite, an inorganic support. The studied lipase was a low cost powdered enzyme preparation, Biolipase-R, from Biocon-Spain, a multipurpose additive used in food industry. In this respect, it is developed a study to optimize the immobilization procedure of these lipases on Sepiolite. Covalent immobilization was achieved by the development of an inorganic-organic hybrid linker formed by a functionalized hydrocarbon chain with a pendant benzaldehyde, bonded to the AlPO4 support surface. Thus, the covalent immobilization of lipases on amorphous AlPO4/sepiolite (20/80 wt %) support was evaluated by using two different linkers (p-hydroxybenzaldehyde and benzylamine-terephthalic aldehyde, respectively). Besides, the catalytic behavior of lipases after physical adsorption on the demineralized sepiolite was also evaluated. Obtained results indicated that covalent immobilization with the p-hydroxybenzaldehyde linker gave the best biocatalytic behavior. Thus, this covalently immobilized lipase showed a remarkable stability as well as an excellent capacity of reutilization (more than five successive reuses) without a significant loss of its initial catalytic activity. This could allow a more efficient fabrication of biodiesel minimizing the glycerol waste production.
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Biocatálise , Biocombustíveis , Enzimas Imobilizadas , Lipase/metabolismo , Óleos de Plantas/química , Rhizopus/enzimologia , Silicatos de Magnésio/química , Óleo de GirassolRESUMO
Plant defenses allow plants to deter or kill their insect herbivores and are considered to be a major driver of host use for herbivorous insects in both ecological and evolutionary time. Many closely related species of insect herbivores differ in their ability to respond to plant defenses and in some cases are specialized to specific plant species. Here we tested whether both mechanical and chemical plant defenses are a major factor in determining the host range of 2 sibling species of Prodoxid bogus yucca moths, Prodoxus decipiens (Riley) and Prodoxus quinquepunctellus (Chambers) that feed within the inflorescence stalk of Yucca species. These 2 moth species have separate suites of host plant species, yet narrowly overlap geographically and share 1 Yucca species, Y. glauca. We surveyed the lignin and cellulose content, the force required to the puncture the stalk tissue, and saponin concentration across 5 Yucca species used as hosts. Lignin, cellulose concentrations, and stalk hardness differed among Yucca species but did not correlate with host use patterns by the moths. Saponin concentrations in the stalk tissue were relatively low for yuccas (<1%) and did not differ among species. The results suggest that these moth species should be able to use each other's hosts for egg deposition. Additional factors such as larval development or competition among larvae for feeding space may serve to keep moth species from expanding onto plants used by its sibling species.
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Mariposas , Yucca , Animais , Dureza , Lignina , Evolução Biológica , Plantas , HerbivoriaRESUMO
BACKGROUND: Recent advances in treatment of malignant brain tumors have improved outcomes. However, patients continue to experience significant disability. Palliative care helps patients with advanced illnesses improve their quality of life. There is a paucity of clinical studies examining palliative care usage among patients with malignant brain tumors. OBJECTIVE: To assess if there were any patterns in palliative care utilization among patients hospitalized with malignant brain tumors. METHODS: A retrospective cohort representing hospitalizations for malignant brain tumors was created from The National Inpatient Sample (2016-2019). Palliative care utilization was identified by ICD-10 code. Univariable and multivariable logistic regression models, accounting for the sample design, were built to evaluate the demographic variables associated with palliative care consultation in all patients and fatal hospitalizations. RESULTS: 375 010 patients admitted with a malignant brain tumor were included in this study. Over the whole cohort, 15.0% of patients used palliative care. In fatal hospitalizations, Black and Hispanic patients had 28% lower odds of receiving a palliative care consultation compared with White patients (odds ratio for both = 0.72; P = .02). For fatal hospitalizations, patients insured privately were 34% more likely to use palliative care services compared with patients insured with Medicare (odds ratio = 1.34, P = .006). CONCLUSION: Palliative care is underutilized among all patients with malignant brain tumors. Within this population, disparities in utilization are exacerbated by sociodemographic factors. Prospective studies investigating utilization disparities across race and insurance status are necessary to improve access to palliative care services for this population.
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Neoplasias Encefálicas , Cuidados Paliativos , Idoso , Humanos , Estados Unidos/epidemiologia , Pacientes Internados , Estudos Retrospectivos , Estudos Prospectivos , Qualidade de Vida , Medicare , Neoplasias Encefálicas/terapiaRESUMO
OBJECTIVE: In this nationwide retrospective study, the authors aimed to identify demographic, clinical, and baseline health risk factors predictive of a prolonged length of stay (PLOS) for patients with pituitary adenomas (PAs). METHODS: The National Inpatient Sample dataset from 2016 to 2019 was utilized to identify all included hospitalizations for PA resection as identified by the appropriate diagnosis-related group code. Comorbidities were classified based on the Charlson Comorbidity Index mapping of ICD-10 codes, and PLOS was identified as any stay longer than 3 days. Univariable and multivariable logistic regression models, accounting for the sample design, were built to determine factors associated with PLOS and emergent surgery. RESULTS: Overall, 30â 945 patients were included in this study with 10â 535 patients having PLOS. Female patients experienced an increased odds of PLOS (odds ratio [OR]: 1.29; P < .001). Black patients (OR: 1.49; P < .001) and Hispanic patients (OR: 1.30; P = .003) had 1.49 times and 1.30 times the odds of PLOS compared to White patients, respectively. Compared to patients insured by Medicare, patients insured by Medicaid had an increased odds of PLOS (OR: 1.36; P = .007) as well as emergent surgery (OR: 5.40; P < .001). When stratified by emergent surgeries, Black patients (OR: 1.89; P < .001), Hispanic patients, (OR: 2.14; P < .001), and patients on Medicaid insurance (OR: 1.71; P < .001) were at an increased risk of emergent procedures. However, female sex (OR: 0.65; P < .001), upper third quartile (OR: 0.73; P = .017), and fourth quartile (OR: 0.69; P = .014) of patients categorized by zip code income were at decreased odds of an emergent procedure. CONCLUSIONS: Black and Hispanic patients, patients with Medicaid insurance, and patients of low socioeconomic status patients are at significantly higher risk of emergent PA resection and PLOS. Efforts to prevent emergent surgeries and shorten hospitalization after pituitary surgery may need to primarily focus on patient groups with select sociodemographic characteristics.
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Neoplasias Hipofisárias , Humanos , Feminino , Idoso , Estados Unidos/epidemiologia , Tempo de Internação , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/cirurgia , Pacientes Internados , Medicare , Estudos RetrospectivosRESUMO
Inflammation and oxidative stress are essential components in a myriad of pathogenic entities that lead to metabolic and chronic diseases. Moreover, inflammation in its different phases is necessary for the initiation and maintenance of a healthy pregnancy. Therefore, an equilibrium between a necessary/pathologic level of inflammation and oxidative stress during pregnancy is needed to avoid disease development. High-density lipoproteins (HDL) are important for a healthy pregnancy and a good neonatal outcome. Their role in fetal development during challenging situations is vital for maintaining the equilibrium. However, in certain conditions, such as obesity, diabetes, and other cardiovascular diseases, it has been observed that HDL loses its protective properties, becoming dysfunctional. Bioactive compounds have been widely studied as mediators of inflammation and oxidative stress in different diseases, but their mechanisms of action are still unknown. Nonetheless, these agents, which are obtained from functional foods, increase the concentration of HDL, TRC, and antioxidant activity. Therefore, this review first summarizes several mechanisms of HDL participation in the equilibrium between inflammation and oxidative stress. Second, it gives an insight into how HDL may act as a vector for bioactive compounds. Third, it describes the relationships between the inflammation process in pregnancy and HDL activity. Consequently, different databases were used, including MEDLINE, PubMed, and Scopus, where scientific articles published in the English language up to 2023 were identified.
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BACKGROUND: Evaluation of interventions on road traffic injuries (RTI) going beyond the assessment of impact to include factors underlying success or failure is an important complement to standard impact evaluations. We report here how we used a qualitative approach to assess current interventions implemented to reduce RTIs in Peru. METHODS: We performed in-depth interviews with policymakers and technical officers involved in the implementation of RTI interventions to get their insight on design, implementation and evaluation aspects. We then conducted a workshop with key stakeholders to analyze the results of in-depth interviews, and to further discuss and identify key programmatic considerations when designing and implementing RTI interventions. We finally performed brainstorming sessions to assess potential system-wide effects of a selected intervention (Zero Tolerance), and to identify adaptation and redesign needs for this intervention. RESULTS: Key programmatic components were consistently identified that should be considered when designing and implementing RTI interventions. They include effective and sustained political commitment and planning; sufficient and sustained budget allocation; training, supervision, monitoring and evaluation of implemented policies; multisectoral participation; and strong governance and accountability. Brainstorming sessions revealed major negative effects of the selected intervention on various system building blocks. CONCLUSIONS: Our approach revealed substantial caveats in current RTI interventions in Peru, and fundamental negative effects on several components of the sectors and systems involved. It also highlighted programmatic issues that should be applied to guarantee an effective implementation and evaluation of these policies. The findings from this study were discussed with key stakeholders for consideration in further designing and planning RTI control interventions in Peru.
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Acidentes de Trânsito/prevenção & controle , Ferimentos e Lesões/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Educação , Feminino , Humanos , Lactente , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Peru , Política Pública , Adulto JovemRESUMO
By using 1,3-specific Pig Pancreatic lipase (EC 3.1.1.3 or PPL), covalently immobilized on AlPO(4)/Sepiolite support as biocatalyst, a new second-generation biodiesel was obtained in the transesterification reaction of sunflower oil with ethanol and other alcohols of low molecular weight. The resulting biofuel is composed of fatty acid ethyl esters and monoglycerides (FAEE/MG) blended in a molar relation 2/1. This novel product, which integrates glycerol as monoacylglycerols (MG) into the biofuel composition, has similar physicochemical properties compared to those of conventional biodiesel and also avoids the removal step of this by-product. The biocatalyst was found to be strongly fixed to the inorganic support (75%). Nevertheless, the efficiency of the immobilized enzyme was reduced to half (49.1%) compared to that of the free PPL. The immobilized enzyme showed a remarkable stability as well as a great reusability (more than 40 successive reuses) without a significant loss of its initial catalytic activity. Immobilized and free enzymes exhibited different reaction mechanisms, according to the different results in the Arrhenius parameters (Ln A and Ea). However, the use of supported PPL was found to be very suitable for the repetitive production of biofuel due to its facile recyclability from the reaction mixture.
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Biocombustíveis , Enzimas Imobilizadas/metabolismo , Ácidos Graxos/metabolismo , Glicerol/metabolismo , Lipase/metabolismo , Álcoois/química , Álcoois/metabolismo , Animais , Cromatografia Gasosa , Enzimas Imobilizadas/química , Esterificação , Ácidos Graxos/química , Glicerol/química , Lipase/química , Óleos de Plantas/química , Óleos de Plantas/metabolismo , Óleo de Girassol , Suínos , Temperatura , ViscosidadeRESUMO
From a technical and economic point of view, our aim is to provide viable solutions for the replacement of fossil fuels which are currently used in internal combustion diesel engines. In this research, two new biofuels composed of second-generation vegetable oils (SVO),used oil sunflower (SO) or castor oil (CO), and the ABE blend (acetone/butanol/ethanol) were evaluated. ABE is an intermediate product from the fermentation of carbohydrates to obtain bio-butanol. Besides, the ABE blend exhibits suitable properties as biofuel, such asvery low kinematic viscosity, reasonable energy density, low autoignition temperature, and broad flammability limits. Diesel/ABE/SVO triple blends were prepared, characterized and then, tested on a diesel engine, evaluating power output, consumption, and exhaust emissions. The power output was slightly reduced due to the low heating values of ABE blend. Also, engine consumed more fuel with the triple blends than with diesel under low engine loads whereas, at medium and high loads, the fuel consumption was very similar to that of diesel. Regarding exhaust gas emissions, soot wasnotably reduced, and nitrogen oxides (NOx) and carbon monoxide (CO2) emissions were lower or comparable to that of diesel, while the CO emissions increased. The use of these biofuels allows the replacement of high percentagesof diesel without compromising engine power and achievinga significant reduction in pollution emissions. Furthermore, a notable improvement in cold flow properties of the fuel blends is obtained, in comparison with diesel.
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Multisystem inflammatory syndrome in children (MIS-C) has been widely reported in some children diagnosed with SARS-CoV-2. Clinical signs of MIS-C are manifested at 2 to 4 weeks after SARS-CoV-2 infection, where elevated biomarkers of inflammation and cardiac dysfunction are the hallmark of this syndrome when infection or exposure to SARS-CoV-2 has been confirmed. However, after two years of acknowledgment, MIS-C treatment is still under research to reach safety and effectiveness in the acute phase in children. Therefore, in this review, we discuss the potential use of natural compounds with antioxidant and anti-inflammatory effects to reduce collateral damage caused by hyperinflammation in MIS-C pathology for new research in treatment and interventions.
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Background: Metabolic syndrome (MetS) has increased worldwide, and since 2012, prevalence of obesity, hypertension, diabetes, and dyslipidemia has increased in Mexico. Objective: To assess the prevalence of MetS, and its relationship with sociodemographic and lifestyle factors among Mexican adults. Methods: Analytical cross-sectional study nationally representative, carried out on Mexican adults (≥20-year-old adults of both sexes; n = 4595). Socioeconomic factors, geographic area, health care coverage and previous medical diagnoses of diabetes and hypertension, and smoking were assessed. Anthropometrics, and triglyceride, total cholesterol, high-density lipoprotein cholesterol (HDL-chol), creatinine, and glucose plasma levels were measured. The ATP III MetS definition was applied. Results: A MetS prevalence of 44.2% was observed, which was higher in males than females, and increased with age, lower school level, and overweight. Hyperglycemia, hypertriglyceridemia, low HDL-chol, abdominal obesity, and hypertension were higher in people with MetS, and were associated with obesity. Conclusions: The prevalence of MetS in the Mexican adult observed in the ENSADER 2007 was high, and mainly in men than women. Specific associations of MetS with age, scholar level, and body mass index have been found. Obesity and MetS were associated.
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Hipertensão , Síndrome Metabólica , Adulto , HDL-Colesterol , Estudos Transversais , Feminino , Humanos , Hipertensão/complicações , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , México/epidemiologia , Obesidade/complicações , Obesidade/epidemiologia , Prevalência , Fatores de Risco , Adulto JovemRESUMO
Obesity is a disease characterized by an inflammatory process in the adipose tissue due to diverse infiltrated immune cells, an increased secretion of proinflammatory molecules, and a decreased secretion of anti-inflammatory molecules. On the other hand, obesity increases the risk of several diseases, such as cardiovascular diseases, diabetes, and cancer. Their treatment is based on nutritional and pharmacological strategies. However, natural products are currently implemented as complementary and alternative medicine (CAM). Polyphenols and fiber are naturally compounds with potential action to reduce inflammation through several pathways and play an important role in the prevention and treatment of obesity, as well as in other non-communicable diseases. Hence, this review focuses on the recent evidence of the molecular mechanisms of polyphenols and dietary fiber, from Scopus, Science Direct, and PubMed, among others, by using key words and based on recent in vitro and in vivo studies.