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1.
J Med Phys ; 49(1): 1-5, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828064

RESUMO

Purpose: To calculate the contribution of absorbed dose by organs in the biokinetics of Tc-99m when used for radiodiagnosis of the adult male heart employing a Matlab program. Methods: The absorbed self-dose of the adult male heart and absorbed dose by organs in the biokinetics of the heart when administering Tc-99m are estimated using the MIRD formalism and the Cristy-Eckerman representation, which have been employed to develop the algorithm in Matlab. Results: The results indicate that electron capture emissions of 1.446 (mGy/MBq) and Auger electrons of 0.062 (mGy/MBq) are entirely directed towards the target organ (heart) and contribute 29.33% and 1.25% respectively to its total dose. Additionally, the dosimetric contributions of biokinetic organs correspond to characteristic radiation emissions and gamma photons at 2.578 (mGy/MBq) for Tc-99m, representing 52.29% of its total dose. Conclusion: These dosimetric contributions are significant in estimating the total absorbed dose by the heart in adult males and should not be disregarded.

2.
Food Sci Technol Int ; : 10820132231166723, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37093761

RESUMO

It is important to understand how the composition and structure of proteins from other flours differ from proteins in wheat, in order to have a better option to substitute gluten products with gluten-free food products. The aim of this study was the characterization of gluten-free flours and comparison of their rheological and calorimetric properties against wheat flour, for its use as gluten-free alternative. Chemical composition analysis, water solubility index (WSI), water absorption index (WAI), texture and calorimetric profile were determined. The closest WAI to wheat flour (1.45 g gel/g sample) was corn flour (2.41 g gel/g sample), while the WSI of chickpea flour was 5.51% approaching that of wheat flour of 5.88%. The hardness and adhesiveness values closest to wheat (1.65 kgf and 0.03 mJ) were amaranth flour with 0.85 kgf and 0.01 mJ, respectively. The phenolic content and antioxidant capacity were higher in the corn and bean flours with 244.4 mg GAE/100 g, 148 mg GAE/100 g and 190 mg AAE/100 g and 170 mg AAE/100 g, respectively. The combination of these non-conventional flours can be an innovative source of gluten-free formulas.

3.
Int J Biol Macromol ; 164: 3429-3437, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32827614

RESUMO

In this study, hard corn grains were nixtamalized (alkali-heat treatment) by a high-energy ball mill to investigate the effects on its physicochemical, textural, and microstructural properties. Ball milling modifies the structure and properties of cornstarch. The gelatinization peak of starch was evidenced and thermal and pasting properties were significantly affected. With regard to rheological properties, the viscosity peak increased from 2454 cP in traditional nixtamalized flour to 4294 cP in high-energy milling treatments with 1.4% of Ca(OH)2 and 20% moisture content, C1.4, while enthalpy ranged from 3.5 to 0.34 J/g, respectively. High-energy milling influenced the Fourier-Transform InfraRed Spectroscopic (FT-IR) patterns. All of the samples of the corn-grain starches presented the typical A-type X-ray diffraction pattern. The crystallinity of starch from CG showed a lower intensity in peaks 2θ ~ 15 and 23° compared with starch from WG and YG. The textural properties of the masas were influenced, adhesiveness was reduced, but cohesiveness was increased by the addition of Ca(OH)2. In the structural characterization by E-SEM, the control presented a greater amount of agglomerated starch granules, followed by the high-energy milling treatments. The results suggest that high-energy alkaline milling could be a potential physical and chemical method to modify corn-starch properties and obtain nixtamalized products.


Assuntos
Álcalis/química , Farinha , Manipulação de Alimentos , Amido/química , Zea mays/química , Fenômenos Químicos , Manipulação de Alimentos/métodos , Termodinâmica , Viscosidade , Difração de Raios X
4.
Insects ; 11(2)2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32013231

RESUMO

We tested the predatory capacity of newly-hatched or newly-molted Chrysoperla comanche (Banks) and Chrysoperla externa (Hagen) larvae after a 24 h fasting period on adults of Frankliniella occidentalis (Pergande) that were feeding on tomato plants (at vegetative and blooming stage) under glasshouse conditions. We also recorded fruit damage by the thrips. Both Chysoperla spp. depredated a similar number of F. occidentalis (thrips) adults regardless of the phenological stage of the plant. Second and third instar larvae of both species consumed significantly more thrips than first instar during plant blooming, however when the plant was at vegetative stage, all larval stages of both species predated a similar number of thrips. A significantly lower fruit damage percentage was recorded at the blooming plant when C. comanche larvae were in the experimental cage, however the presence of second and third instar of both species significantly reduced the fruit damage. No foliar damage was recorded. As far as we know, this is the first assessment of the predatory capacity of C. comanche and C. externa on thrips feeding on tomato under glasshouse conditions.

5.
Heliyon ; 5(4): e01506, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31183413

RESUMO

A modified clay cup (cantarito) microbial fuel cell (C-MFCs) was designed to digest the biomass effluent from a nopal biogas (NBE). To improve the process, commercial acrylic varnish (AV) was applied to the C-MFCs. The experiment was performed as:Both-C-MFCs, painting of AV on both sides of the clay cup; In-C-MFCs, painting of AV on the internal side, and Out-C-MFCs painting of AV on the external side. The order for the maximum volumetric power densities were Both-C-MFCs (1841.99 mW/m3)>Out-C-MFCs (1023.74 mW/m3) >In-C-MFCs (448.90 mW/m3). The control experiment without applied varnish did not show a stable potential, supporting the idea that the acryloyl group in varnish could favor the performance. Finally, a 4-digits clock was powered with two, Both-C-MFCs connected in series; the microbial diversity in this format was explored and a well-defined bacterial community including members of the phyla Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, Synergistetes and candidate division TM7 was found.

6.
Plant Foods Hum Nutr ; 74(2): 241-246, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31001726

RESUMO

This study aimed at evaluating the effect of high-energy milling (HEM) and traditional nixtamalization (TN) on bioactive compounds and antioxidant capacity in nixtamalized creole corn flours obtained from a maize genotype cultivated under rainy temporal conditions in the Mexican semidesert. Four creole grains, including San José de Gracia white and blue (WG and BG), Negritas (NG), and Ahualulco white corn grains (SG), were used. For HEM nixtamalization, corn grains were hammer-milled; then, two different conditions were evaluated: treatment H1, with raw flours with 14% moisture content and 1.1% Ca(OH)2, and treatment H2, with raw corn flours with a 23% moisture content and 1.4% Ca(OH)2. The TN process was utilized as a control. TN recorded significant losses in luminosity value L* (p < 0.05), while HEM nixtamalized blue corn flours remained close to -b* values, that is, near to those of raw flour. Anthocyanin content showed higher content values in HEM treatments compared with TN (759.55 and 252.53 mg cyanidin 3-O-ß-D-glucoside (C3G)/kg, respectively) (p < 0.05). Total soluble phenolic content was higher in HEM nixtamalization compared with the traditional process, except for WH2 and SH2 (H2 treatment for WG and SG). Two redundant radical scavenging assays were used: antioxidant capacity (DPPH assay) exhibited less value in nixtamalized flours than in raw flour (p < 0.05). Antioxidant activity by (ABTS) assay was higher in HEM than in TN. Nixtamalized flours produced by HEM demonstrated more improvement in nutraceutical properties than those produced employing TN.


Assuntos
Antioxidantes/metabolismo , Manipulação de Alimentos/métodos , Compostos Fitoquímicos/metabolismo , Zea mays/química , Antocianinas/análise , Antocianinas/metabolismo , Antioxidantes/análise , Suplementos Nutricionais , Grão Comestível/química , Farinha/análise , México , Fenóis/análise , Fenóis/metabolismo , Compostos Fitoquímicos/análise
7.
Food Chem ; 283: 481-488, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30722902

RESUMO

High-energy milling (HEM) was used to produce nixtamalized corn flours, the traditional nixtamalization process was used as a control. Four creole grains were stone-milled, adjusted to an appropriate moisture content and calcium hydroxide concentration and milled using HEM. The physicochemical, thermal, and rheological characteristics of the flours and corn masas were affected by the HEM process. Negritas and Ahualulco creole grains nixtamalized by HEM showed similar viscosity profiles as a control. HEM reduced the gelatinization enthalpy compared to control and raw flours. Diffractograms showed changes in the crystalline structures and FT-IR demonstrated different regions for lipids, proteins, and carbohydrates in all control and treated grains. The texture of corn masas revealed significant differences according to the grain type. ESEM analysis showed smaller particles of HEM flours compared to those of the control. HEM could be a faster, non-pollutant, energy-saving, alternative nixtamalization process.


Assuntos
Farinha , Manipulação de Alimentos/métodos , Zea mays/química , Farinha/análise , Microscopia Eletrônica de Varredura , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Difração de Raios X
8.
Food Chem ; 278: 601-608, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583418

RESUMO

The aim of this work was to evaluate the effect of the addition of huitlacoche paste to nixtamalized blue-corn flours (NBCF) on the physicochemical, thermal, and rheological properties of masas. Raw blue maize was nixtamalized (hydrothermal alkalinized process), then was wet-milled in a stone mill, masa was dehydrated, pulverized and sieved to obtain NBCF; commercial nixtamalized blue-corn flour (CNBCF) was used as a control. Huitlacoche paste in concentrations of 3, 6, 9, 12, 15, and 18% was added to nixtamalized flours. Characteristics of the blue grain showed its great effects on water absorption, viscosity, and masa cohesiveness; the addition of huitlacoche significantly influenced adhesiveness, water-absorption, color, and the rheological properties (p < 0.05). Values between 0.03 and 0.083 kg-force resulted in masas with optimal adhesiveness. The inclusion of huitlacoche paste can be achieved with a maximal addition of 9% in NBCF for an industrial process and could comprise a new industrialization alternative.


Assuntos
Farinha/análise , Ustilago/crescimento & desenvolvimento , Zea mays/química , Cor , Reologia , Solubilidade , Viscosidade , Água/química , Zea mays/metabolismo
9.
Endosc Int Open ; 5(12): E1172-E1178, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29202000

RESUMO

BACKGROUND AND STUDY AIMS: Addition of a reminder program to conventional indications improves colonoscopy. The aim of this study was to evaluate the effectiveness of a short telephone call reminder (STCR) on a patient's first colonoscopy. PATIENTS AND METHODS: One day before colonoscopy, we made a STCR of < 10 minutes to 141 randomly selected patients of 258 recruited. The STCRs informed patients about the procedure date, indications for taking laxatives, and dietetic requirements. Questions were clarified only when patients asked directly. We evaluated bowel preparation, quality indicators, and patient satisfaction. Data were expressed as mean ±â€ŠSD and percentages. Statistical differences were evaluated by Student's t and Chi squared tests; alpha = 0.05. All authors had access to the study data and reviewed and approved the final manuscript. RESULTS: The STCR group had better bowel preparation which was demonstrated by higher completion frequency (97.16 % vs. 82.05 %), in less time (4.52 ±â€Š3.06 vs. 5.38 ±â€Š3.03 hours) intake of laxative, and higher Boston's scale (7.66 ±â€Š2.42 vs. 5.2 ±â€Š1.65). Quality indicators of colonoscopy were better in patients that received a STCR [cecal intubation rate: 100.00 % vs. 87.18 %; polyp detection: 42.55 % vs. 9.4 %; and cecal arrival time (min): 12.09 ±â€Š3.62 vs. 15.09 ±â€Š5.02]. STCR patients were more satisfied (97.87 % vs. 55.56 %) and would repeat colonoscopy (21.99 % vs. 11.11 %). CONCLUSIONS: A simple additional step such as a STCR improves quality of bowel preparation, quality indicators, and satisfaction of patients undergoing their first colonoscopy. Clinical trial registry in Mexico City General Hospital: DI/16/107/3/108.

11.
ScientificWorldJournal ; 2012: 341764, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629131

RESUMO

Chili pepper blight observed on pepper farms from north Aguascalientes was monitored for the presence of Phytophthora capsici during 2008-2010. Initially, ELISA tests were directed to plant samples from greenhouses and rustic nurseries, showing an 86% of positive samples. Later, samples of wilted plants from the farms during the first survey were tested with ELISA. The subsequent survey on soil samples included mycelia isolation and PCR amplification of a 560 bp fragment of ITS-specific DNA sequence of P. capsici. Data was analyzed according to four geographical areas defined by coordinates to ease the dispersal assessment. In general, one-third of the samples from surveyed fields contained P. capsici, inferring that this may be the pathogen responsible of the observed wilt. Nevertheless, only five sites from a total of 92 were consistently negative to P. capsici. The presence of this pathogen was detected through ELISA and confirmed through PCR. The other two-thirds of the negative samples may be attributable to Fusarium and Rhizoctonia, both isolated instead of Phytophthora in these areas. Due to these striking results, this information would be of interest for local plant protection committees and farmers to avoid further dispersal of pathogens to new lands.


Assuntos
Capsicum/parasitologia , Phytophthora/patogenicidade , Doenças das Plantas/parasitologia , Doenças das Plantas/estatística & dados numéricos , México
12.
Nahrung ; 47(5): 334-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14609090

RESUMO

Chemical and biochemical changes were studied in ripening prickly pears from three Opuntia morphospecies with different ripening behaviour: Naranjona (O. ficus-indica), Blanca Cristalina (Opuntia sp.), and Charola (O. streptacantha), of early, intermediate, and late ripening, respectively. At fullyripe stage (commercial maturity), Blanca Cristalina showed the biggest fruits, the hardest texture, and its pulp had the highest protein content. There were no significant differences among morphospecies in pH or total soluble solids in fully ripe fruits. The three species exhibited considerable levels of vitamin C, dietary fibre, and minerals such as calcium, iron, and zinc. Protein expression was analysed in pulp and skin from every species at physiological and commercial maturity. Some proteins appeared at both stages, while many others expressed differentially. This study evaluated prickly pear components important for human nutrition and health, and provided basic information on pricky pear ripening, with a view to its control and to improving shelf life.


Assuntos
Frutas/química , Opuntia , Proteínas de Plantas/análise , Ácido Ascórbico/análise , Fibras na Dieta/análise , Manipulação de Alimentos/métodos , Concentração de Íons de Hidrogênio , Minerais/análise , Valor Nutritivo , Opuntia/química , Opuntia/classificação , Opuntia/fisiologia , Solubilidade , Especificidade da Espécie , Fatores de Tempo
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