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1.
Acad Pediatr ; 24(5S): 95-97, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38991816

RESUMO

We are Latinx immigrants and children of Latinx immigrants. We provided emergency volunteer services at the Mission Food Bank during the pandemic to provide food assistance to low-income families in the Mission District and the city of San Francisco. In March 2021, we were invited to lead a research project that we call "We are Essential". Here we share our process and a few of our findings on the mental health of San Francisco's Latinx community during the pandemic, with a focus on our children and youth. A full report of our findings will be published in 2024.


Assuntos
COVID-19 , Assistência Alimentar , Hispânico ou Latino , Saúde Mental , Humanos , COVID-19/etnologia , COVID-19/psicologia , Hispânico ou Latino/psicologia , Criança , Adolescente , São Francisco , Saúde Mental/etnologia , Emigrantes e Imigrantes/psicologia , Pandemias , Feminino , SARS-CoV-2 , Masculino , Pobreza
2.
Neotrop Entomol ; 52(1): 104-113, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36626092

RESUMO

A multiple nucleopolyhedrovirus native isolate (SfCH32) of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) was encapsulated by spray-drying in a matrix based on oxidized corn starch without and with a fluorescent brightener. The microcapsules were exposed to UV radiation (365 nm) for 0, 2, 4, and 8 h at 25 °C or temperatures of 35, 40, and 45 °C for 8 h. The data obtained with temperatures 35, 40, and 45 °C were contrasted with those obtained at 25 °C. The microcapsules were evaluated for size, shape, and insecticidal capacity against third instar S. frugiperda larvae under laboratory conditions. The 82-84.2% of the encapsulating matrix, in a dry-weight basis, was recovered as NPV microcapsules of heterogeneous shape and size. The exposure to UV radiation and temperatures reduced significantly the insecticidal capacity of tested viruses; however, such capacity was higher for microencapsulated than for non-microencapsulated viruses. The non-encapsulated virus that had been exposed to 45 °C or maintained at UV radiation for 8 h showed the lowest insecticidal activity at 5th day post-inoculation, with a larvae mortality of 25.3 and 16%, respectively. The fluorescent brightener increased significantly the insecticidal capacity of encapsulated and non-encapsulated viruses, causing a mortality of 100% at that time point, and decreased the median lethal time independently of the incubation temperature and exposure time to radiation. The findings suggested that an encapsulating matrix based on oxidized corn starch might protect the insecticidal capacity of NPV under field conditions.


Assuntos
Inseticidas , Nucleopoliedrovírus , Animais , Spodoptera , Raios Ultravioleta , Temperatura , Zea mays , Cápsulas , Controle Biológico de Vetores , Larva
3.
Molecules ; 27(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35164171

RESUMO

The objective of this study was to obtain and characterize flours and starches from the avocado seeds of Hass and landrace cultivars. The morphological, physical-chemical, structural, thermal and rheological characteristics were evaluated. The flour yield of the Hass and landrace cultivars was 41.56 to 46.86% (w/w), while for starch, it was 35.47 to 39.57% (w/w) (cv. Hass and landrace, respectively). Scanning electron microscopy (SEM) revealed the presence of oval starch granules and other particles in flour, in contrast to flours, starches showed lower ash, proteins and lipids content. However, the amylose content was higher in starches (42.25-48.2%). Flours showed a higher gelatinization temperature (Tp = 73.17-73.62 °C), and their starches presented greater gelatinization enthalpy (∆Hgel = 11.82-13.43 J/g). All samples showed a B-type diffraction pattern, and the crystallinity was higher in the flours. The rheological analysis (flow curves and viscoelastic tests) evidenced a pseudoplastic (n = 0.28-0.36) behavior in all samples analyzed, but the consistency index (k) was higher in starches. In general, the flours and starches from avocado seeds presented interesting proximal, thermal and functional properties for possible application in food systems, and these findings could contribute to the revaluation of this by-product.


Assuntos
Farinha , Persea/química , Sementes/química , Amido/química , Amilose/análise , Farinha/análise , Temperatura Alta , Reologia , Termodinâmica , Viscosidade
4.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209163

RESUMO

The feasibility of obtaining resistant starch type III (RS3) from malanga flour (Xanthosoma sagittifolium), as an unconventional source of starch, was evaluated using the hydrothermal treatment of autoclaving. The physicochemical characterization of RS3 made from malanga flour was carried out through the evaluation of the chemical composition, color attributes, and thermal properties. In addition, the contents of the total starch, available starch, resistant starch, and retrograded resistant starch were determined by in vitro enzymatic tests. A commercial corn starch sample was used to produce RS3 and utilized to compare all of the analyses. The results showed that native malanga flour behaved differently in most of the evaluations performed, compared to the commercial corn starch. These results could be explained by the presence of minor components that could interfere with the physicochemical and functional properties of the flour; however, the RS3 samples obtained from malanga flour and corn starch were similar in their thermal and morphological features, which may be related to their similarities in the content and molecular weight of amylose, in both of the samples. Furthermore, the yields for obtaining the autoclaved powders from corn starch and malanga flour were similar (≈89%), which showed that the malanga flour is an attractive raw material for obtaining RS3 with adequate yields, to be considered in the subsequent research.


Assuntos
Farinha , Amido Resistente , Xanthosoma/química , Zea mays/química
5.
Molecules ; 26(6)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810043

RESUMO

High molecular weight chitosan (≈322 kDa) was obtained from chitin isolated from Brachystola magna (Girard) to produced biodegradable films. Their physicochemical, mechanical and water vapor permeability (WVP) properties were compared against commercial chitosan films with different molecular weights. Brachystola magna chitosan films (CFBM) exhibited similar physicochemical and mechanical characteristics to those of commercial chitosans. The CFBM films presented lower WVP values (10.01 × 10-11 g/m s Pa) than commercial chitosans films (from 16.06 × 10-11 to 64.30 × 10-11 g/m s Pa). Frankfurt-type sausages were covered with chitosan films and stored in refrigerated conditions (4 °C). Their quality attributes (color, weight loss, pH, moisture, texture and lipid oxidation) were evaluated at 0, 5, 10, 15 and 20 days. Sausages covered with CFMB films presented the lowest weight loss (from 1.24% to 2.38%). A higher increase in hardness (from 22.32 N to 30.63 N) was observed in sausages covered with CFMB films. Compared with other films and the control (uncovered sausages), CFMB films delay pH reduction. Moreover, this film presents the lower lipid oxidation level (0.10 malonaldehyde mg/sample kg). Thus, chitosan of B. magna could be a good alternative as packaging material for meat products with high-fat content.


Assuntos
Quitosana/química , Embalagem de Alimentos , Conservação de Alimentos , Gafanhotos/química , Produtos da Carne , Membranas Artificiais , Animais
6.
Trans R Soc Trop Med Hyg ; 115(6): 579-582, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33693916

RESUMO

A cohort study of Filipino tuberculosis patients is currently undergoing data collection amidst the coronavirus disease 2019 pandemic. In this article we present the current experiences, challenges and obstacles of our team during this period as we attempt to fulfil our roles and responsibilities in Metro Manila, Cebu and Negros Occidental in the Philippines. Each site had different lockdown restrictions and experienced problems to different degrees. The underlying themes were similar, covering the supply chain, mobility, communication, physical and mental health and disruption of health services due to reallocation of staff. While we maximized the use of mobile devices, logistical challenges remained. Institutional support for the field teams, creative problem solving and resilience are required to adapt in a rapidly changing environment.


Assuntos
COVID-19 , Tuberculose , Estudos de Coortes , Controle de Doenças Transmissíveis , Humanos , Filipinas/epidemiologia , SARS-CoV-2 , Tuberculose/epidemiologia
7.
Int J Biol Macromol ; 160: 953-963, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497671

RESUMO

Insects are considered as alternative sources of chitosan; however, studies about the functional film-forming properties of insect chitosan are scarce. Insect chitosan films were made from Tenebrio molitor and Brachystola magna and were compared with commercial chitosan of different molecular weights (Mw). Mechanical properties (tensile strength, TS; elastic modulus, EM; elongation at break, %E), water vapor permeability (WVP) and physicochemical properties were characterized. The film properties of both commercial and insect chitosan were affected by Mw. Commercial chitosan films showed that at lower Mw, the TS (from 59 to 48 MPa) and EM (from 1471 to 1286 MPa) decreased; whereas WVP (from 2.9 × 10-11 to 3.4 × 10-11 g m-1s-1Pa-1), % E (from 38 to 41%) and solubility (from 30 to 33%) increased. Chitosan insect films showed lower TS and EM, and higher WPV, %E and solubility than commercial films. SEM revealed that chitosan insect films had lower porosity than commercial films. FTIR and X-ray diffraction showed not difference between insect and commercial chitosan films. These results showed that T. molitor and B. magna chitosan films could be used as a packaging material in several food products.


Assuntos
Quitosana/química , Membranas Artificiais , Tenebrio/química , Animais , Fenômenos Químicos , Fenômenos Mecânicos , Peso Molecular , Reologia , Solubilidade , Análise Espectral , Vapor
8.
Foods ; 8(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366054

RESUMO

This study reports the effect of the addition of oat bran and apple flour on the cooking quality, digestibility, antioxidant, nutritional and texture characteristics of a spaghetti-type pasta. Pasta samples were prepared by substituting 50% of durum wheat semolina with oat bran (OBP) or apple flour (AFP). AFP presented higher cooking loss and water absorption index than the control pasta prepared with 100% durum wheat semolina (WSP). The supplementation of pasta with oat bran increased the total dietary fiber content (16.43% w/w, dw), while apple flour decreased the protein content (11.16% w/w, dw). There was no significant difference in the resistant starch content among all pasta samples. The pasta samples made with 50/50 durum wheat semolina/oat bran and 50/50 durum wheat semolina/apple flour increased the antioxidant activity by ≈46% and ≈97%, respectively. The OBP and AFP samples had a similar texture to the control pasta. A 50% replacement of durum wheat semolina with oat bran in a pasta formulation decreased the caloric content and digestibility of its starch components. These attributes found in the oat bran pasta and apple flour pasta make them a healthy choice for the diet of people with specific nutritional needs.

9.
J Invertebr Pathol ; 159: 71-77, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30312627

RESUMO

European foulbrood (EFB) caused by Melissococcus plutonius is an important bee brood disease but, in Mexico, information about this bacterium is limited. We evaluated the prevalence of typical and atypical strains in beehives of seven apicultural regions of the state of Chihuahua, Mexico. We performed MLST and phylogenetic analysis to characterize the isolates. Prevalence was highest 59%, in the region of Chihuahua, and lowest, 14%, in the regions of Cuauhtémoc and Nuevo Casas Grandes. Typical and atypical strains were identified in hives from all regions; however, in the regions of Parral, Cuauhtémoc and Aldama, the atypical strains were only detected in combination with typical strains. We obtained 81 isolates of M. plutonius and identified seven sequence types, of which three were new types. Additionally, we observed a relation between sequence type and the region where the strain was isolated. Phylogenetic analysis and multilocus sequence typing using goeBURST analysis showed that 97.5% of the isolates correspond to the Clonal Complex (CC) 12 and 2.5% to the CC3. Our work is the first molecular characterization of M. plutonius in Mexico and contributes to global information about the epidemiology of this pathogen.


Assuntos
Abelhas/microbiologia , Enterococcaceae/fisiologia , Filogenia , Animais , Larva/microbiologia , México , Prevalência
10.
Int J Biol Macromol ; 98: 341-347, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28167109

RESUMO

Chayotextle starch was modified by subjecting it to a dual treatment with acid and heating-cooling cycles. This caused a decrease in the content of amylose, which showed values of 30.22%, 4.80%, 3.27% and 3.57% for native chayotextle starch (NCS), starch modified by acid hydrolysis (CMS), and CMS with one (CMS1AC) and three autoclave cycles (CMS3AC), respectively. The percentage of crystallinity showed an increase of 36.9%-62% for NCS and CMS3AC. The highest content of resistant starch (RS) was observed in CMS3AC (37.05%). The microcapsules were made with CMS3AC due to its higher RS content; the total content of ascorbic acid of the microcapsules was 82.3%. The addition of different concentrations of CMS3AC microcapsules (0%, 2.5%, 6.255% and 12.5%) to chayotextle starch-based films (CSF) increased their tensile strength and elastic modulus. The content of ascorbic acid and RS in CSF was ranged from 0% to 59.4% and from 4.84% to 37.05% in the control film and in the film mixed with CMS3AC microcapsules, respectively. Water vapor permeability (WVP) values decreased with increasing concentrations of microcapsules in the films. Microscopy observations showed that higher concentrations of microcapsules caused agglomerations due their poor distribution in the matrix of the films.


Assuntos
Ácido Ascórbico/química , Cucurbitaceae/química , Amido/química , Amilose/análise , Cápsulas , Digestão , Hidrólise , Fenômenos Mecânicos , Permeabilidade , Amido/metabolismo , Vapor
11.
Mol Biotechnol ; 58(10): 657-664, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27394727

RESUMO

Codon optimization of the Bos taurus Chymosin gene (CYM) for its expression in Pichia pastoris was performed in this study. A synthetic CYM gene was designed in silico by replacing codons rarely used by P. pastoris with equivalent nucleotide combinations that codify for the same amino acid but that are more frequently encountered in the genome of P. pastoris. A total of 332 nucleotides were modified to optimize 289 codons. The synthetic CYM gene was cloned into the expression vector pPICZαA and transformed into P. pastoris. The transformed strains were grown in artificial media supplemented with glycerol as a carbon source to increase biomass and then cultured in a similar medium replacing glycerol with methanol as a carbon source to initiate gene induction. Raw extracts of the growth media exhibited milk-clotting activity of 146.11 SU/mL. Produced recombinant chymosin showed coagulant activity from 25 to 50 °C, and within a pH range of 5-6.9, having optimum activity at 35-40 °C, and pH 5.0. These results show that codon optimization is a viable strategy to improve CYM gene expression levels in P. pastoris for the production of recombinant chymosin.


Assuntos
Quimosina/genética , Quimosina/metabolismo , Pichia/genética , Análise de Sequência de DNA/métodos , Animais , Bovinos , Códon , Meios de Cultura/química , Genes Sintéticos , Proteínas Recombinantes/metabolismo , Transformação Genética
12.
Carbohydr Polym ; 115: 112-21, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25439875

RESUMO

Water-, chelator-, and alkali-soluble pectins were isolated from raw and heat-processed Jalapeño peppers (green and red) and their physiochemical and rheological properties were determined. The yield, tristimulus color, degree of methyl esterification, monosaccharide composition, molecular weights distribution, and protein content depended on ripening and heat processing. The viscosity properties of pectins were independent of ripening. The water-soluble pectin was the most abundant pectin. Pectins from grilled peppers showed the lowest L* values. The alkali-soluble pectin showed the highest protein content. The content of xylose, rhamnose, and mannose in pectins was highly altered by tested factors. The degree of methyl esterification of pectins ranged from 26.8 to 91.6%. The peak Mw of the main fraction of tested pectins was sequentially reduced by ripening and heat processing. Pectins from raw peppers showed the best viscosity properties.


Assuntos
Temperatura Alta , Pectinas/química , Piperaceae/química , Reologia , Físico-Química , Pectinas/isolamento & purificação , Solubilidade , Viscosidade
13.
Molecules ; 18(11): 13735-53, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24213653

RESUMO

Chitosan films (CF) with carvacrol (CAR) [0.5%, 1.0% and 1.5% v/v] were prepared by the emulsion method. The retained CAR, water solubility, water vapor permeability (WVP), optical, mechanical properties, antibacterial and antioxidant capacity of films were analyzed. The results indicate that the retention of CAR in the CF was ≈50%. The incorporation of CAR to CF decreased the water solubility, the WVP, the yellowing and transparency and the tensile strength, but increased the stiffness. Microcapsules with diameters of 2 to 7 µm were found on the surface CF-CAR. The CF-CAR with highest CAR concentrations showed antibacterial activity against S. typhimurium and E. coli O157:H7. The CF-CAR had higher antioxidant capacity and an increased protective effect against oxidation of erythrocytes in different grades. These results suggest potential applications of CF-CAR as active packaging to preserve food products.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Quitosana/química , Monoterpenos/química , Cimenos , Microscopia de Força Atômica
14.
J Agric Food Chem ; 61(41): 9938-49, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24047354

RESUMO

Raw and heat-processed (boiled and grilled) jalapeño peppers at three intermediate ripening stages (brown, 50% red, and 75% red) were digested in vitro without fat and in the presence of soybean oil (SO) or beef tallow (BT), and the micellarization of their lipid soluble pigments (LSP) was measured. The micelles from digestions with brown, 50% red, and 75% red peppers contained up to 27, 35, and 29 different LSP, respectively. Boiling and grilling decreased the micellarization of LSP from brown peppers, whereas the opposite was observed with 75% red peppers. Heat processing did not clearly affect the micellarization of LSP from 50% red fruits. The impact of fat on LSP micellarization was ripening-dependent, but the micellarization of the less polar carotenoids was always increased by SO or BT. This positive effect of fat was higher with SO than with BT.


Assuntos
Capsicum/química , Culinária/métodos , Gorduras/química , Pigmentos Biológicos/química , Verduras/química , Capsicum/crescimento & desenvolvimento , Carotenoides/química , Frutas/química , Frutas/crescimento & desenvolvimento , Temperatura Alta , Verduras/crescimento & desenvolvimento
15.
Case Rep Med ; 2012: 575470, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22924046

RESUMO

We report a case of Strongyloides stercoralis hyperinfection syndrome with central nervous system involvement, in a patient with late human immunodeficiency virus (HIV) infection starting antiretroviral therapy, in whom Strongyloides stercoralis larvae and Cryptococcus neoformans were isolated antemortem from cerebrospinal fluid. Our patient was not from an endemic region for the parasite, so strongyloidiasis was not originally suspected. For this reason, we conclude that Strongyloides stercoralis infection should be suspected in HIV-infected patients starting antiretroviral therapy in order to avoid potential fatal outcomes.

16.
J Food Sci ; 75(6): E347-52, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20722919

RESUMO

Mucilage of Opuntia ficus-indica (OFI) was extracted and characterized by its composition and molecular weight distribution. Mucilage film-forming dispersions were prepared under different pHs (3, 4, 5.6, 7, and 8) and calcium concentration (0% and 30% of CaCl(2), with respect to mucilage's weight), and their particle size determined. Mucilage films with and without calcium (MFCa and MF, respectively) were prepared. The effect of calcium and pH on mucilage films was evaluated determining thickness, color, water vapor permeability (WVP), tensile strength (TS), and percentage of elongation (%E). The average molecular weight of the different fractions of mucilage was: 3.4 x 10(6) (0.73%), 1 x 10(5) (1.46%), 1.1 x 10(3) (45.79%), and 2.4 x 10(2) Da (52.03%). Aqueous mucilage dispersions with no calcium presented particles with an average size d(0.5) of 15.4 microm, greater than the dispersions with calcium, 13.2 microm. MFCa films showed more thickness (0.13 mm) than the MF films (0.10 mm). The addition of calcium increased the WVP of the films from 109.94 to 130.45 gmm/m(2)dkPa. Calcium and pH affected the mechanical properties of the films; the largest TS was observed on MF films, whereas the highest %E was observed on MFCa films. The highest differences among MF and MFCa films were observed at pHs 5.6 and 7 for TS and at pHs 4 and 8 for %E. No effect of pH and calcium was observed on luminosity and hue angle. Chroma values were higher for MF when compared with MFCa, and increased as pH of the films increased. Practical Application: In this study mucilage from nopal was extracted and characterized by its ability to form edible films under different pHs, and with or without the addition of calcium. Opuntia ficus-indica mucilage had the ability to form edible films. In general, it can be considered that mucilage films without modification of pH and without the addition of calcium have the best water vapor barrier properties and tensile strength. Mucilage from nopal could represent a good option for the development of edible films in countries where nopal is highly produced at low cost, constituting a processing alternative for nopal.


Assuntos
Cloreto de Cálcio/química , Embalagem de Alimentos , Opuntia/química , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Cálcio da Dieta/análise , Fenômenos Químicos , Carboidratos da Dieta/análise , Elasticidade , Concentração de Íons de Hidrogênio , Concentração Osmolar , Tamanho da Partícula , Permeabilidade , Pigmentação , Extratos Vegetais/isolamento & purificação , Proteínas de Plantas/análise , Vapor , Resistência à Tração , Água/análise
17.
Buffalo, N.Y; U.S. Multicidisciplinary Center for Earthquake Engineering Research (MCEER); Oct. 1999. 57 p. ilus, mapas, tab.(Technical Report MCEER-99-0017).
Monografia em En | Desastres | ID: des-12646

RESUMO

At 13:19 local time (18:19 GMT),on Monday, January 25th, 1999 an earthquake with magnitude 6.2 on the Ritcher scale ocurried in the western part of Colombia. The earthquake caused approximately 1,200 deaths and 5,000 injuries, damaged or destroyed 50,000 structures, and displaced more than 200,000 persons from their homes throughout an area extending some 50 kilometers from the epicenter. Economic losses are estimated to exceed $2 billion. This report describes the types and causes of damage resulting from the earthquake and the resulting social and economic impacts


Assuntos
Terremotos , Avaliação de Danos , Economia , Fatores Socioeconômicos , 32465 , Efeitos de Desastres nas Edificações , Colômbia
18.
In. UN. Centre for Regional Development; Japan. Japanese Government Headquartes for the IDNDR; Aichi Prefectural Government; Japan. National Committee for the IDNDR; World Bank. Disaster Management in Metropolitan Areas for the 21st Century : Proceedings of the IDNDR Aichi/Nagoya International Conference 1993 Japan. Nagoya, UN. Centre for Regional Development, Mar. 1994. p.535-40, ilus, mapas, Tab.
Monografia em En | Desastres | ID: des-5836

RESUMO

Much has been learned from the lessons of the Loma Prieta earthquake of 1989. Some of the highlights of the major changes that California has made to its disaster management systems were presented in this paper. Many other lessons were learned in the areas of hazard mitigation, earthquake prediction and public warnings, and disaster recovery. Many of the other initiatives promoted by the Loma Prieta earthquake will positively affect efforts to reduce disaster management problems. In California, we have come to view hazards reduction from a holistic perspective and our general approach has become much more comprehensive. Much remains to be done in reducing our vulnerability to natural disasters. In California, we have answered the call for making the 1990s the Inetrnational Decade for Natural Disaster Reduction. We certainly welcome every opportubity, such as IDNDR ANIC'93, to share our disaster reduction wisdom with others worldwide(AU)


Assuntos
Terremotos , Avaliação de Danos , Estados Unidos , Planejamento em Desastres , Comunicações Via Satélite
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