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1.
J Appl Clin Med Phys ; 23(7): e13623, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35486368

RESUMO

A linear accelerator has three independent axes that are nominally intersecting at the isocenter. Modern treatment techniques require the coincidence of these axes to lie within a 1-mm diameter sphere. A solution to verify this requirement is to wrap a film on a cylindrical surface, align the cylinder to the linac's isocenter and gantry axis, and take multiple exposures of slits, rotating either the gantry, collimator, or couch between exposures. The resulting exposure pattern is the 3D equivalent of the 2D star shot and encodes sufficient information to determine each axis' position in 3D. Moreover, this method uses a single sheet 8"x10" film, a standard film scanner, and a phantom that can be readily built in-house, making a practical solution to this 3D-measurement problem.


Assuntos
Aceleradores de Partículas , Humanos , Imagens de Fantasmas
2.
Molecules ; 25(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316621

RESUMO

Individual glucosinolates (GSLs) were assessed to select cabbage genotypes for a potential breeding program. One hundred forty-six cabbage genotypes from different origins were grown in an open field from March to June 2019; the cabbage heads were used for GSL analyses. Seven aliphatics [glucoiberin (GIB), progoitrin (PRO), epi-progoitrin (EPI), sinigrin (SIN), glucoraphanin (GRA), glucoerucin (GER) and gluconapin (GNA)], one aromatic [gluconasturtiin (GNS)] and four indolyl GSLs [glucobrassicin (GBS), 4-hydroxyglucobrassicin (4HGBS), 4-methoxyglucobrassicin (4MGBS), neoglucobrassicin (NGBS)] were found this study. Significant variation was observed in the individual GSL content and in each class of GSLs among the cabbage genotypes. Aliphatic GSLs were predominant (58.5%) among the total GSLs, followed by indolyl GSL (40.7%) and aromatic GSLs (0.8%), showing 46.4, 51.2 and 137.8% coefficients of variation, respectively. GIB, GBS and NGBS were the most common GSLs found in all genotypes. GBS was the most dominant GSL, with an average value of 3.91 µmol g-1 (0.79 to 13.14 µmol g-1). SIN, GIB, PRO and GRA were the other major GSLs, showing average values of 3.45, 1.50, 0.77 and 0.62 µmol g-1, respectively. The genotypes with relatively high contents of GBS, SIN, GIB and GRA warrant detailed studies for future breeding programs since the hydrolysis products of these GSLs have several anti-cancer properties.


Assuntos
Brassica/química , Glucosinolatos/química , Sementes/química , Brassica/genética , Cromatografia Líquida de Alta Pressão , Variação Genética , Genótipo , Indóis/química , Metabolômica/métodos , Melhoramento Vegetal , Seleção Genética
3.
Nanotechnology ; 28(29): 295301, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28594335

RESUMO

Molybdenum disulfide (MoS2), as one of the atomically thin two-dimensional transition metal dichalcogenides has novel layer-dependent optical and electronic properties, which make it competitive for potential applications in optoelectronics. Here, we report chemical vapor deposition growth of vertically-standing and planar spiral MoS2 nanosheets. These vertical spiral MoS2 nanosheets are formed by the compression between planar spiral MoS2 in a close proximity. Both structures have a polytype 3R stacking with broken inversion symmetry, exhibiting strong second and third harmonic generations.

4.
Molecules ; 21(7)2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27428947

RESUMO

A comprehensive overview of current research progress on boron nitride nanotubes (BNNTs) is presented in this article. Particularly, recent advancements in controlled synthesis and large-scale production of BNNTs will first be summarized. While recent success in mass production of BNNTs has opened up new opportunities to implement the appealing properties in various applications, concerns about product purity and quality still remain. Secondly, we will summarize the progress in functionalization of BNNTs, which is the necessary step for their applications. Additionally, selected potential applications in structural composites and biomedicine will be highlighted.


Assuntos
Compostos de Boro/química , Nanotubos/química , Materiais Biocompatíveis/química , Compostos de Boro/síntese química , Técnicas de Química Sintética , Nanotubos/ultraestrutura , Polímeros/química , Relação Estrutura-Atividade
5.
BMC Pediatr ; 15: 133, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26391586

RESUMO

BACKGROUND: In resource-limited nations like Nepal, congenital defects, including neural tube defects (NTDs), have great public health impact. NTDs and a few other congenital defects can be prevented by micronutrient supplementation. Without proper research regarding such defects, it is difficult to assess the damage made to health and productivity. This study aims to investigate different congenital defects among children in Nepal. METHODS: Household surveys and health camps were conducted from 2011 to 2012. Physical examination of women of reproductive age (15 to 49 years) was done in selected Village Development Committees of nine districts in three ecological regions of Nepal. Congenital defects, including NTDs, were examined in children (age 0 to 5 years) who were alive at the time of the survey. Data entry and analysis was performed by using SPSS version 11.5. RESULTS: 21,111 women were interviewed and 27,201 children born to them were assessed. The prevalence of congenital defects was 52.0 (95% CI: 44.0-61.0) per 10,000 children. The prevalence of selected NTDs was 4.0 (95% CI: 2.0-7.0) per 10,000 children. Among the neural tube defects, encephalocele, myelomeningocele and dermal sinus were the major ones, having almost the same prevalence in the Hill and Terai regions. The majority of children with genital abnormalities (17.0 per 10,000 children; 95% CI: 10.0-28.0) and limb deformities (14.0 per 10,000 children; 95% CI: 8.0-24.0) were found in the Terai. The rate of congenital birth defects was higher in the regions where women were in poor health. CONCLUSION: There is high prevalence of congenital defects in Nepal. Since such defects add a burden to families and society, it is imperative that health policies addressing programs like supplementation, fortification and dietary diversification be implemented.


Assuntos
Inquéritos Epidemiológicos , Defeitos do Tubo Neural/epidemiologia , Saúde Pública , Adolescente , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Nepal/epidemiologia , Prevalência , Estudos Retrospectivos , Adulto Jovem
6.
Molecules ; 20(1): 1228-43, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25591122

RESUMO

This research was conducted to evaluate glucosinolate profiles, vitamin C, total phenol, total flavonoid, and free sugar (glucose, fructose, and sucrose) content, fatty acid composition, and antioxidant activity in floret and leaf of six cauliflower and broccoli cultivars. The level of chemical constituents as well as antioxidants significantly varied among crop types, cultivars, and their different parts, in that phytochemicals such as glucosinolate were statistically higher in florets compared with leaves in both broccoli and cauliflower cultivars. In contrast, total flavonoid and free sugar were found at higher levels in the leaf parts. The Asia purple cultivar exhibited statistically higher vitamin C (649.7 mg·100 g-1), total phenol (1345.2 mg·GAE 100 g-1), and total flavonoid (632.7 mg·CE 100 g-1) contents and consequently had the highest antioxidant activity (1.12 mg·mL-1) in its florets, while Baeridom and Bridal had the highest total glucosinolate (9.66 µmol·g-1) and free sugar (318.6 mg·g-1) contents, respectively compared with other cultivars. Likewise, the major fatty acids were palmitic (23.52%-38.42%), linoleic (13.09%-18.97%), and linolenic (26.32%-51.80%) acids, which comprised the highest compositional ratio (more than 50%) of polyunsaturated fatty acids (PUFAs) in most cultivars. Among the antioxidants, total phenol exhibited the most significant positive correlation (r = 0.698 **) with antioxidant activity, followed by vitamin C (r = 0.522 **) and total flavonoid (r = 0.494 **), indicating their significant contributions to total antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Brassica/química , Antioxidantes/química , Carboidratos/análise , Cromatografia DEAE-Celulose , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/análise , Flavonoides/análise , Glucosinolatos/análise
7.
Molecules ; 20(9): 15827-41, 2015 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-26334264

RESUMO

Glucosinolate (GSL) profiles and concentrations in various tissues (seeds, sprouts, mature root, and shoot) were determined and compared across nine Brassica species, including cauliflower, cabbage, broccoli, radish, baemuchae, pakchoi, Chinese cabbage, leaf mustard, and kale. The compositions and concentrations of individual GSLs varied among crops, tissues, and growth stages. Seeds had highest total GSL concentrations in most of crops, whereas shoots had the lowest GSL concentrations. Aliphatic GSL concentrations were the highest in seeds, followed by that in sprouts, shoots, and roots. Indole GSL concentration was the highest in the root or shoot tissues in most of the crops. In contrast, aromatic GSL concentrations were highest in roots. Of the nine crops examined, broccoli exhibited the highest total GSL concentration in seeds (110.76 µmol·g(-1)) and sprouts (162.19 µmol·g(-1)), whereas leaf mustard exhibited the highest total GSL concentration in shoots (61.76 µmol·g(-1)) and roots (73.61 µmol·g(-1)). The lowest GSL concentrations were observed in radish across all tissues examined.


Assuntos
Brassica/química , Produtos Agrícolas/química , Glucosinolatos/análise , Raízes de Plantas/química , Sementes/química
8.
Adv Nutr ; 15(5): 100203, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38462217

RESUMO

Livelihoods have changed dramatically over the past decade in low- and middle-income countries (LMIC). These shifts are happening in tandem with shifts in individual and household food choice behaviors. This scoping review aimed to identify and characterize mechanisms through which livelihood changes could affect food choice behaviors in LMIC, including behaviors relating to food production, acquisition, preparation, distribution, and consumption. A literature search was conducted using 4 databases: PubMed, PsycInfo, AGRICOLA, and Embase. The search was further enhanced by expert solicitations. Studies were included if they measured or focused on a livelihood change, described or assessed a change in ≥1 food choice behavior, and focused on LMIC. Studies were excluded if they focused on migration from LMIC to a high-income country. Of the 433 articles that were identified, 53 met the inclusion criteria. Five mechanisms of how livelihood change can affect food choice were identified: occupation, locality, time, income, and social relations. Changes in occupation altered the balance of the availability and affordability of foods in local food environments compared with individual food production. Changes in location, time use, and income influenced where food was purchased, what types of foods were acquired, and how or where foods were prepared. Additionally, changes in social relationships and norms led to expanded food preferences, particularly among urban populations. Time limitations and higher discretionary income were associated with consumption of ultraprocessed foods. Understanding the relationships between the changes in livelihood occuring in LMIC and food choices of households in these countries can inform the development of policies, programs, and other actions to promote sustainable healthy diets and planetary health.


Assuntos
Comportamento de Escolha , Países em Desenvolvimento , Preferências Alimentares , Renda , Humanos , Preferências Alimentares/psicologia , Abastecimento de Alimentos , Fatores Socioeconômicos , Pobreza , Características da Família , Comportamento Alimentar/psicologia
9.
Curr Dev Nutr ; 7(1): 100015, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37181131

RESUMO

Background: Consumption of unsafe foods increases morbidity and mortality and is currently an issue, particularly in low- and middle-income countries. Policy actions to ensure food safety are dominated by mitigation of biological and chemical hazards through supply-side risk management, lessening the degree to which consumer perspectives of food safety are considered. Objectives: This study aimed to provide an in-depth understanding, from vendor and consumer perspectives, of how food-safety concerns of consumers translate into their subsequent food-choice behaviors in 6 diverse low- and middle-income countries. Methods: Six Drivers of Food Choice projects (2016-2022) provided transcripts from 17 focus group discussions and 343 interviews conducted in Ghana, Guinea, India, Kenya, Tanzania, and Vietnam. Qualitative thematic analysis was used to identify emerging themes important to food safety. Results: The analysis suggests that consumers constructed meaning about food safety through personal lived experience and social influences. Community and family members contributed knowledge about food safety. Concerns about food safety were influenced by reputations of and relationships with food vendors. Consumers' mistrust of food vendors was amplified by purposeful adulteration or unsafe selling practices and new methods used to produce food. Moreover, consumers were reassured of food safety by positive relationships with vendors; meals cooked at home; implementation of policies and following regulations; vendor adherence to environmental sanitation and food-hygiene practices; cleanliness of vendors' appearance; and vendors' or producers' agency to use risk mitigation strategies in production, processing, and distribution of food. Conclusions: Consumers integrated their meanings, knowledge, and concerns about food safety to achieve assurance about the safety of their foods when making food-choice decisions. The success of food-safety policies hinges on consideration of consumers' food-safety concerns in their design and implementation, alongside actions to reduce risk in food supply.

10.
J Biomed Opt ; 27(7)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35818115

RESUMO

SIGNIFICANCE: Light is a good probe for studying the nanoscale-level structural or molecular-specific structural properties of brain cells/tissue due to stress, alcohol, or any other abnormalities. Chronic alcoholism during pregnancy, i.e., fetal alcoholism, being teratogenic, results in fetal alcohol syndrome, and other neurological disorders. Understanding the nano-to-submicron scale spatial structural properties of pup brain cells/tissues using light/photonic probes could provide a plethora of information in understanding the effects of fetal alcoholism. AIM: Using both light scattering and light localization techniques to probe alterations in nano- to-submicron scale mass density or refractive index fluctuations in brain cells/tissues of mice pups, exposed to fetal alcoholism. APPROACH: We use the mesoscopic physics-based dual spectroscopic imaging techniques, partial wave spectroscopy (PWS) and molecular-specific inverse participation ratio (IPR) using confocal imaging, to quantify structural alterations in brain tissues and chromatin/histone in brain cells, respectively, in 60 days postnatal mice pup brain, exposed to fetal alcoholism. RESULTS: The finer focusing PWS analysis on tissues shows an increase in the degree of structural disorder strength in the pup brain tissues. Furthermore, results of the molecular-specific light localization IPR technique show an increase in the degree of spatial molecular mass density structural disorder in DNA and a decrease in the degree in histone. CONCLUSIONS: In particular, we characterize the spatial pup brain structures from the molecular to tissue levels and address the plausible reasons for such as mass density fluctuations in fetal alcoholism.


Assuntos
Alcoolismo , Transtornos do Espectro Alcoólico Fetal , Nanoestruturas , Animais , Encéfalo/diagnóstico por imagem , Feminino , Transtornos do Espectro Alcoólico Fetal/diagnóstico por imagem , Histonas , Humanos , Camundongos , Óptica e Fotônica , Gravidez
11.
Food Nutr Bull ; 43(4): 412-428, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35726207

RESUMO

BACKGROUND: In homestead food production (HFP) programs, village model farmers (VMFs), after training, implement agriculture and nutrition activities to improve household knowledge and practices. Little evidence exists on what enables VMFs to remain actively engaged and for impacts to be sustained. OBJECTIVE: To examine variables explaining active engagement of VMFs, at least 4 years post-training, in an HFP program in Nepal. METHODS: We used cross-sectional data, collected from 2018 to 2019, among 4750 VMFs of Suaahara, a multisectoral nutrition program. We assessed whether respondents registered their HFP group with the local government, conducted regular group meetings, discussed vegetable growing and chicken rearing practices with group members, or engaged in saving and credit activities in their HFP group. Outcome variable was a count of these 4 activities in which the VMF engaged. Socioeconomic, demographic, and programmatic explanatory variables were identified a priori and by bivariate analysis and were adjusted in ordinal regression models accounting for clusters. RESULTS: On average, VMFs engaged in 1.4 activities. Having attended primary or secondary school (adjusted odds ratios [AOR] = 1.39), being a female community health volunteer (AOR = 1.27), being from an advantaged caste/ethnic group (AOR = 1.34), receiving additional trainings (AOR = 1.56) and inputs (AOR = 1.31) were associated with more active engagement of VMFs. CONCLUSION: Village model farmers receiving more training and inputs were more likely to remain actively engaged. Female community health workers, people from higher caste/ethnic groups, and those with primary or secondary education were more likely to remain active VMFs and could be targeted for this role in HFP programs leading to sustained impact.


Assuntos
Fazendeiros , Estado Nutricional , Feminino , Humanos , Estudos Transversais , Nepal , Agricultura
12.
Foods ; 12(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36613336

RESUMO

This study monitored changes in major carotenoids (lutein, ⍺-carotene, and ß-carotene), free sugars (fructose, glucose, and sucrose), ascorbic acid, vitamin E, phytosterols (campesterol, stigmasterol, and ß-sitosterol), fatty acid composition, total phenol content (TPC), total flavonoid content (TFC), total anthocyanin content, and antioxidant activities (AA); ferric-reducing antioxidant power (FRAP) and 2,2'-azino-bis (3-ethylbenzothiazoline-6sulfonic acid) [ABTS] assays, in the inner and outer root tissues of nine carrot genotypes with orange, white, and purple roots. The results showed a differential accumulation of bioactive compounds and antioxidant activities depending on root tissue and color. Carotenoids, free sugars, and total phytosterol contents were higher in genotypes with orange roots than in other genotypes. Ascorbic acid, TPC, TFC, total anthocyanin, and AA were highest in purple-colored carrots while vitamin E content was higher in white/purple carrots. Root color was highly related to the accumulation of individual carotenoids, vitamin E isomers, and total anthocyanin content most prominently among the analyzed bioactive compounds and AA. Free sugar and carotenoid contents were relatively higher in outer tissues than in inner tissues. Furthermore, ascorbic acid, TPC, TFC, and AA were statistically higher or similar in outer tissues when compared to inner tissues in all genotypes. In contrast, trends in vitamin E and phytosterol content were inconsistent between the inner and outer tissues, depending on the genotype. Although fatty acid composition was affected by both root color and tissue, the results were not significant. Thus, the phytochemical profile and content were highly dependent on root color and tissue in carrot genotypes. This may be useful in the food processing and pharmaceutical industries for the extraction of targeted bioactive compounds.

13.
Front Plant Sci ; 12: 786309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003172

RESUMO

Chlorophyll fluorescence (CF) is used to measure the physiological status of plants affected by biotic and abiotic stresses. Therefore, we aimed to identify the changes in CF parameters in grafted watermelon seedlings exposed to salt, drought, and high and low temperatures. Grafted watermelon seedlings at the true three-leaf stage were subjected to salinity levels (0, 50, 100, 150, and 200 mM) and temperature [low (8°C), moderate (24°C), and high (40°C)] stresses for 12 days under controlled environmental conditions independently. Eight CF parameters were measured at 2-day intervals using the FluorCam machine quenching protocol of the FluorCam machine. The seedlings were also exposed to drought stress for 3 days independent of salinity and temperature stress; CF parameters were measured at 1-day intervals. In addition, growth parameters, proline, and chlorophyll content were evaluated in all three experiments. The CF parameters were differentially influenced depending on the type and extent of the stress conditions. The results showed a notable effect of salinity levels on CF parameters, predominantly in maximum quantum yield (Fv/Fm), non-photochemical quenching (NPQ), the ratio of the fluorescence decrease (Rfd), and quantum yield of non-regulated energy dissipation in PSII [Y(NO)]. High temperature had significant effects on Rfd and NPQ, whereas low temperature showed significant results in most CF parameters: Fv/Fm, Y(NO), NPQ, Rfd, the efficiency of excitation capture of open photosystem II (PSII) center (Fv'/Fm'), and effective quantum yield of photochemical energy conversion in PSII [Y(PSII)]. Only NPQ and Rfd were significantly influenced by severe drought stress. Approximately, all the growth parameters were significantly influenced by the stress level. Proline content increased with an increase in stress levels in all three experiments, whereas the chlorophyll (a and b) content either decreased or increased depending upon the stressor. The results provided here may be useful for understanding the effect of abiotic stresses on CF parameters and the selection of index CF parameters to detect abiotic stresses in grafted watermelon seedlings.

14.
Curr Dev Nutr ; 4(2): nzaa003, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31998859

RESUMO

We tested whether a multisectoral household agricultural and finance intervention increased the dietary intake and improved the nutritional status of HIV-affected children. Two hospitals in rural Kenya were randomly assigned to be either the intervention or the control arm. The intervention comprised a human-powered water pump, microfinance loan for farm commodities, and training in sustainable farming practices and financial management. In each arm, 100 children (0-59 mo of age) were enrolled from households with HIV-infected adults 18-49 y old. Children were assessed beginning in April 2012 and every 3 mo for 1 y for dietary intake and anthropometry. Children in the intervention arm had a larger increase in weight (ß: 0.025 kg/mo, P = 0.030), overall frequency of food consumption (ß: 0.610 times · wk-1 · mo-1, P = 0.048), and intakes of staples (ß: 0.222, P = 0.024), fruits and vegetables (ß: 0.425, P = 0.005), meat (ß: 0.074, P < 0.001), and fat (ß: 0.057, P = 0.041). Livelihood interventions have potential to improve the nutrition of HIV-affected children. This trial was registered at clinicaltrials.gov as NCT01548599.

15.
Nutrients ; 12(1)2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31963752

RESUMO

Animal source foods (ASF) provide nutrients essential to child growth and development yet remain infrequently consumed in rural Nepal. Agriculture and nutrition programs aim to increase ASF intake among children through small-scale animal husbandry projects. The relationship between livestock ownership and children's consumption of ASF, however, is not well established. This study examined associations between livestock ownership and the frequency with which Nepali children consume eggs, dairy, and meat. We analyzed longitudinal 7-day food frequency data from sentinel surveillance sites of the Policy and Science of Health, Agriculture and Nutrition (PoSHAN) study. Data consisted of surveys from 485 Nepali farming households conducted twice per year for two years (a total of 1449 surveys). We used negative binomial regression analysis to examine the association between the number of cattle, poultry, and meat animals (small livestock) owned and children's weekly dairy, egg, and meat intakes, respectively, adjusting for household expenditure on each food type, mother's education level, caste/ethnicity, agroecological region, season, and child age and sex. We calculated predicted marginal values based on model estimates. Children consumed dairy 1.4 (95% CI 1.1-2.0), 2.3 (1.7-3.0) and 3.0 (2.1-4.2) more times per week in households owning 1, 2-4 and >4 cattle, respectively, compared to children in households without cattle. Children consumed eggs 2.8 (2.1-3.7) more times per week in households owning 1 or 2 chickens compared to children in households without chickens. Child intake of meat was higher only in households owning more than seven meat animals. Children's intakes of dairy, eggs, and meat rose with household expenditure on these foods. Small-scale animal production may be an effective strategy for increasing children's consumption of eggs and dairy, but not meat. Increasing household ability to access ASF via purchasing appears to be an important approach for raising children's intakes of all three food types.


Assuntos
Criação de Animais Domésticos , Laticínios , Ovos , Abastecimento de Alimentos , Carne , Saúde da População Rural , Fatores Etários , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Inquéritos sobre Dietas , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Masculino , Nepal , Estado Nutricional , Valor Nutritivo , Recomendações Nutricionais , Fatores de Tempo
16.
J Biophotonics ; 12(6): e201800002, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30523668

RESUMO

Chronic stress affects nano to microscale structures of the brain cells/tissues due to suppression of neural growths and reconnections, hence the neuronal activities. This results in depression, memory loss and even death of the brain cells. Our recently developed novel optical technique, partial wave spectroscopic microscopy has nanoscale sensitivity, and hence, can detect nanoscale changes in brain tissues due to stress. In this study, we applied this technique to quantify the stress related structural changes in the corticosterone-treated mouse model of stress. Our results show that brains from corticosterone-treated mice showed higher nanoscale structural disorder in the hippocampal region as compared to the brain from normal (vehicle) mice. The increase in structural alteration correlates with the duration of the stress. We further quantified the relative changes and the spatial localization of these changes in this mouse model and found out that the maximum changes occurred nearly symmetrically in both regions of the hippocampus. The mRNA for stress-related genes, brain-derived neurotrophic factor and tyrosine kinase-coupled receptor were also significantly reduced in the hippocampus of corticosterone-treated mice compared to that in control mice. These results indicate that chronic corticosterone treatment induces nanoscale structural alterations in mouse brain that corresponds to changes in stress-related gene expression.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Corticosterona/farmacologia , Microscopia , Fenômenos Ópticos , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Camundongos , Proteínas Tirosina Quinases/metabolismo , Análise Espectral
17.
ACS Nano ; 13(4): 4347-4353, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30946561

RESUMO

Metallic gold nanoparticles (Au NPs) with multilayer Au atoms are useful for plasmonic, chemical, medical, and metamaterial application. In this article, we report the opening of the bandgap in substrate-supported two-dimensional (2D) gold quantum dots (Au QDs) with monolayer Au atoms. Calculations based on density functional theory suggest that 2D Au QDs are energetically favorable over 3D Au clusters when coated on hexagonal boron nitride (BN) surfaces. Experimentally, we find that BN nanotubes (BNNTs) can be used to stabilize 2D Au QDs on their cylindrical surfaces as well as Au atoms, dimers, and trimers. The electrically insulating and optically transparent BNNTs enable the detection of the optical bandgaps of the Au QDs in the visible spectrum. We further demonstrate that the size and shapes of 2D Au QDs could be atomically trimmed and restructured by electron beam irradiation. Our results may stimulate further exploration of energetically stable, metal-based 2D semiconductors, with properties tunable atom by atom.

18.
Int Breastfeed J ; 14: 14, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30988689

RESUMO

Background: Optimal breastfeeding practices, reflected by early initiation and feeding of colostrum, avoidance of prelacteal feeds, and continued exclusivity or predominance of breastfeeding, are critical for assuring proper infant nutrition, growth and development. Methods: We used data from a nationally representative survey in 21 district sites across the Mountains, Hills and Terai (southern plains) of Nepal in 2013. Determinants of early initiation of breastfeeding, feeding of colostrum, prelacteal feeding and predominant breastfeeding were explored in 1015 infants < 12 months of age. Prelacteal feeds were defined as food/drink other than breast milk given to newborns in first 3 days. Predominant breastfeeding was defined as a child < 6 months of age is mainly breastfed, not fed solid/semi-solid foods, infant formula or non-human milk, in the past 7 days. Adjusted prevalence ratios (APR) and 95% confidence intervals (CI) were estimated, using log Poisson regression models with robust variance for clustering. Results: The prevalence of breastfeeding within an hour of birth, colostrum feeding, prelacteal feeding and predominant breastfeeding was 41.8, 83.5, 32.7 and 57.2% respectively. Compared to infants not fed prelacteal feeds, infants given prelacteal feeds were 51% less likely to be breastfed within the first hour of birth (APR 0.49; 95% CI 0.36, 0.66) and 55% less likely to be predominantly breastfed (APR 0.45; 95% CI 0.32, 0.62). Infants reported to have received colostrum were more likely to have begun breastfeeding within an hour of birth (APR 1.26; 95% CI 1.04, 1.54) compared to those who did not receive colostrum. Infants born to mothers ≥ 20 years of age were less likely than adolescent mothers to initiate breastfeeding within 1 hour of birth. Infants in the Terai were 10% less likely to have received colostrum (APR 0.90; 95% CI 0.83, 0.97) and 2.72 times more likely to have received prelacteal feeds (APR 2.72; 95% CI 1.67, 4.45) than those in the Mountains. Conclusions: Most infants in Nepal receive colostrum but less than half initiate breastfeeding within an hour of birth and one-third are fed prelacteal feeds, which may negatively affect breastfeeding and health throughout early infancy.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Adulto , Aleitamento Materno/psicologia , Colostro/metabolismo , Feminino , Inquéritos Epidemiológicos , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Masculino , Mães/estatística & dados numéricos , Nepal , Gravidez , Fatores de Tempo , Adulto Jovem
19.
PLoS One ; 13(11): e0205438, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30403683

RESUMO

BACKGROUND: The 2015 earthquake in Nepal caused massive damages and triggered relief activities to minimize human suffering. The post-earthquake nutrition and food security situation in the hardest hit areas remains uncertain. METHODS: Two national cross-sectional surveys were conducted in 2014 and 2016 among households (HH) with pre-school aged children or newly married women. Of the 21 village development committees (VDCs) included in this sample, 7 fell within "earthquake-affected" areas. This paper presents data from 982 HH, 1015 women, and 883 children from 2014 and 1056 HH, 1083 women, and 998 children from 2016 living in these areas, with longitudinal overlap of about 55%. Prevalence estimates and 95% confidence intervals were calculated, and logistic regression was used to calculate p-values, both using robust estimates of standard errors to account for clustering. RESULTS: From 2014 to 2016, child wasting (weight-for-height z score <-2) fell from 4.5% (95% CI 3.3%- 6.1%) to 2.1% (1.4%- 3.1%) and food insecurity (assessed using the household food insecurity access scale) dropped from 17.6% (11.7%- 25.6%) to 12.4% (6.9%- 21.2%). Child stunting prevalence remained similar at both time-points. Improvements were also evident in dietary diversity and breastfeeding indicators. CONCLUSIONS: Nutrition and food security conditions remained comparable or improved one year after the earthquake despite evidence of structural and other damage. Livelihood resilience to shocks and/or effective nutrition, food or health interventions may have helped buffer the impact on nutrition, although this hypothesis requires further exploration.


Assuntos
Terremotos , Abastecimento de Alimentos , Estado Nutricional , Adolescente , Adulto , Criança , Estudos Transversais , Terremotos/história , Características da Família , História do Século XXI , Humanos , Nepal , Prevalência , Vigilância em Saúde Pública , Fatores Socioeconômicos , Adulto Jovem
20.
J Biophotonics ; 11(12): e201800056, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29869394

RESUMO

As cancer progresses, macromolecules, such as DNA, RNA or lipids, inside cells undergo spatial structural rearrangements and alterations. Mesoscopic light transport-based optical partial wave spectroscopy (PWS) was recently introduced to quantify changes in the nanoscale structural disorder in biological cells. The PWS measurement is performed using a parameter termed as "disorder strength" (L d ), which represents the degree of nanoscale structural disorder inside the cells. It was shown that cancerous cells have higher disorder strength than normal cells. In this work, we first used the PWS to analyze the hierarchy of different types of prostate cancer cells, namely, C4-2, DU-145 and PC-3, by quantifying their average disorder strengths. Results expectedly showed that L d values increases in accordance with the increasing aggressiveness/tumorigenicity levels of these cells. Using the L d parameter, we then analyzed the chemoresistance properties of these prostate cancer cells to docetaxel drug compared to their chemosensitivity. Results show that chemoresistant cancer cells have increased L d values, that is, higher disorder strength, relative to chemosensitive cancer cells. Thus, use of the L d metric can be effective in determining the efficacy of particular chemotherapy.


Assuntos
Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Análise Espectral , Linhagem Celular Tumoral , Humanos , Masculino , Resultado do Tratamento
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