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1.
Health Aff (Millwood) ; 43(9): 1329-1337, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-39226495

RESUMEN

COVID-19-related school closures may have had unintended consequences affecting the ability of health professionals with school-age children to work-particularly female professionals, who often have disproportionate child care responsibilities. We combined labor-force participation data from the Current Population Survey with measures of school closures based on cell phone mobility data to examine the association between local school closures and labor supply among female nurses during the COVID-19 pandemic. During the six months after large-scale closure of schools at the end of the 2019-20 school year (March-August 2020), among counties with above-median school closure rates, the employment rate of female nurses with young children declined by 12.5 percentage points versus the rate during the prior four months (November 2019-February 2020); the change in the employment rate in below-median counties was not statistically significant. No statistically significant changes were observed among female nurses who had only older children or among male nurses. During public health emergencies, policies should consider how disruptions to schooling may affect the labor supply of health care professionals. Strategies might include direct provision of child care by health care facilities, subsidies and other aid to child care centers, or subsidies to health care workers for affordable child care.


Asunto(s)
COVID-19 , Empleo , Instituciones Académicas , Humanos , COVID-19/epidemiología , Femenino , Empleo/estadística & datos numéricos , Adulto , Estados Unidos , Niño , Enfermeras y Enfermeros/provisión & distribución , SARS-CoV-2 , Pandemias , Masculino
2.
Sci Data ; 10(1): 471, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37474611

RESUMEN

In-situ marine cloud droplet number concentrations (CDNCs), cloud condensation nuclei (CCN), and CCN proxies, based on particle sizes and optical properties, are accumulated from seven field campaigns: ACTIVATE; NAAMES; CAMP2EX; ORACLES; SOCRATES; MARCUS; and CAPRICORN2. Each campaign involves aircraft measurements, ship-based measurements, or both. Measurements collected over the North and Central Atlantic, Indo-Pacific, and Southern Oceans, represent a range of clean to polluted conditions in various climate regimes. With the extensive range of environmental conditions sampled, this data collection is ideal for testing satellite remote detection methods of CDNC and CCN in marine environments. Remote measurement methods are vital to expanding the available data in these difficult-to-reach regions of the Earth and improving our understanding of aerosol-cloud interactions. The data collection includes particle composition and continental tracers to identify potential contributing CCN sources. Several of these campaigns include High Spectral Resolution Lidar (HSRL) and polarimetric imaging measurements and retrievals that will be the basis for the next generation of space-based remote sensors and, thus, can be utilized as satellite surrogates.

3.
Int J Pharm ; 642: 123132, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37315638

RESUMEN

Through 3D printing (3DP), many parameters of solid oral dosage forms can be customised, allowing for truly personalised medicine in a way that traditional pharmaceutical manufacturing would struggle to achieve. One of the many options for customisation involves dose titration, allowing for gradual weaning of a medication at dose intervals smaller than what is available commercially. In this study we demonstrate the high accuracy and precision of 3DP dose titration of caffeine, selected due to its global prevalence as a behavioural drug and well-known titration-dependent adverse reactions in humans. This was achieved using a simple filament base of polyvinyl alcohol, glycerol, and starch, utilising hot melt extrusion coupled with fused deposition modelling 3DP. Tablets containing 25 mg, 50 mg, and 100 mg doses of caffeine were successfully printed with drug content in the accepted range prescribed for conventional tablets (90 - 110%), and excellent precision whereby the weights of all doses showed a relative standard deviation of no more than 3%. Importantly, these results proved 3D printed tablets to be far superior to splitting a commercially available caffeine tablet. Additional assessment of filament and tablet samples were reviewed by differential scanning calorimetry, thermogravimetric analysis, HPLC, and scanning electron microscopy, showing no evidence of degradation of caffeine or the raw materials, with smooth and consistent filament extrusion. Upon dissolution, all tablets achieved greater than 70% release between 50 and 60 min, showing a predictable rapid release profile regardless of dose. The outcomes of this study highlight the benefits that dose titration with 3DP can offer, especially to more commonly prescribed medications that can have even more harmful withdrawal-induced adverse reactions.


Asunto(s)
Cafeína , Alcohol Polivinílico , Humanos , Cafeína/química , Comprimidos/química , Alcohol Polivinílico/química , Tecnología de Extrusión de Fusión en Caliente , Impresión Tridimensional , Liberación de Fármacos , Tecnología Farmacéutica/métodos
4.
Heart Lung Circ ; 32(1): 67-78, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36463077

RESUMEN

BACKGROUND AND AIM: COVID-19 can be transmitted through aerosolised respiratory particles. The degree to which exercise enhances aerosol production has not been previously assessed. We aimed to quantify the size and concentration of aerosol particles and evaluate the impact of physical distance and surgical mask wearing during high intensity exercise (HIE). METHODS: Using a prospective observational crossover study, three healthy volunteers performed high intensity cardiopulmonary exercise testing at 80% of peak capacity in repeated 5-minute bouts on a cycle ergometer. Aerosol size and concentration was measured at 35, 150 and 300 cm from the participants in an anterior and lateral direction, with and without a surgical face mask, using an Aerodynamic Particle Sizer (APS) and a Mini Wide Range Aerosol Spectrometer (MiniWRAS), with over 10,000 sample points. RESULTS: High intensity exercise generates aerosol in the 0.2-1 micrometre range. Increasing distance from the rider reduces aerosol concentrations measured by both MiniWRAS (p=0.003 for interaction) and APS (p=0.041). However, aerosol concentrations remained significantly increased above baseline measures at 300 cm from the rider. A surgical face mask reduced submicron aerosol concentrations measured anteriorly to the rider (p=0.031 for interaction) but not when measured laterally (p=0.64 for interaction). CONCLUSIONS: High intensity exercise is an aerosol generating activity. Significant concentrations of aerosol particles are measurable well beyond the commonly recommended 150 cm of physical distancing. A surgical face mask reduces aerosol concentration anteriorly but not laterally to an exercising individual. Measures for safer exercise should emphasise distance and airflow and not rely solely on mask wearing.


Asunto(s)
COVID-19 , Humanos , Estudios Cruzados , Aerosoles y Gotitas Respiratorias , Pulmón , Máscaras
5.
Labour Econ ; 72: 102060, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34493904

RESUMEN

The COVID-19 pandemic significantly affected data collection for the nation's primary source of household-level labor force data, the Current Population Survey (CPS). In the first four months of the pandemic period (March-June 2020) the average month-over-month nonresponse rate increased by 58 percent, while the size of newly entering cohorts declined by 37 percent relative to the prior 15 months. Together, these factors reduced the overall sample size of the CPS by around 16 percent. We hypothesize that these changes, and significant associated shifts in the demographic composition of the sample, were caused by the cessation of in-person interviewing. Geographic variation in nonresponse over this period does not appear related to variation in COVID case rates across metro areas or states. Using this change in interview method as a natural experiment, we compare labor market outcomes of those who entered the survey pre- and post-COVID pandemic and find that the change in how individuals were recruited into the survey affected estimates of unemployment and labor force participation. In an exercise generating a counterfactual group of "missing" respondents, we estimate that, between April and August of 2020, the average unemployment rate was 0.5 to 0.7 percentage points higher, and the labor force participation rate was 0.4 to 0.8 percentage points lower than estimates using the actual sample of respondents. One implication of these results is that web-based surveys, which are increasingly relied on in empirical labor market studies, may fail to reach important subpopulations of the labor market and that reweighting is unlikely to address the selection on outcomes we document.

6.
Membranes (Basel) ; 11(6)2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34072746

RESUMEN

Liposomes are spherical-shaped vesicles that enclose an aqueous milieu surrounded by bilayer or multilayer membranes formed by self-assembly of lipid molecules. They are intensively exploited as either model membranes for fundamental studies or as vehicles for delivery of active substances in vivo and in vitro. Irrespective of the method adopted for production of loaded liposomes, obtaining the final purified product is often achieved by employing multiple, time consuming steps. To alleviate this problem, we propose a simplified approach for concomitant production and purification of loaded liposomes by exploiting the Electrodialysis-Driven Depletion of charged molecules from solutions. Our investigations show that electrically-driven migration of charged detergent and dye molecules from solutions that include natural or synthetic lipid mixtures leads to rapid self-assembly of loaded, purified liposomes, as inferred from microscopy and fluorescence spectroscopy assessments. In addition, the same procedure was successfully applied for incorporating PEGylated lipids into the membranes for the purpose of enabling long-circulation times needed for potential in vivo applications. Dynamic Light Scattering analyses and comparison of electrically-formed liposomes with liposomes produced by sonication or extrusion suggest potential use for numerous in vitro and in vivo applications.

7.
Health Aff (Millwood) ; 40(5): 837-843, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33881908

RESUMEN

The COVID-19 pandemic has disrupted access to medical care for millions of Americans, yet information on the individual characteristics associated with these disruptions is lacking. We used recently released data from the Current Population Survey's supplemental COVID-19 questions to provide the first evidence on associations between individual characteristics, including age, sex, race/ethnicity, education, health status, work-limiting disabilities, health insurance coverage, and employment, and the propensity to experience an involuntary care disruption resulting from the COVID-19 pandemic. Involuntary care disruption is defined as delayed or cancelled care that was not initiated by the patient. Results indicate that older age, being in fair or poor health, greater education, and having health insurance coverage were associated with greater likelihood of experiencing an involuntary delay in accessing medical care. In addition, White, non-Hispanic respondents had higher rates of involuntary care delays than respondents of other races/ethnicities. Our findings provide useful guidance for researchers examining the health consequences of COVID-19-related care disruptions and for policy makers developing tools to offset the potential harms of such disruptions.


Asunto(s)
COVID-19 , Pandemias , Anciano , Atención a la Salud , Humanos , SARS-CoV-2 , Estados Unidos , Población Blanca
8.
Pituitary ; 24(4): 499-506, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33469830

RESUMEN

PURPOSE: To determine the particle size, concentration, airborne duration and spread during endoscopic endonasal pituitary surgery in actual patients in a theatre setting. METHODS: This observational study recruited a convenience sample of three patients. Procedures were performed in a positive pressure operating room. Particle image velocimetry and spectrometry with air sampling were used for aerosol detection. RESULTS: Intubation and extubation generated small particles (< 5 µm) in mean concentrations 12 times greater than background noise (p < 0.001). The mean particle concentrations during endonasal access were 4.5 times greater than background (p = 0.01). Particles were typically large (> 75 µm), remained airborne for up to 10 s and travelled up to 1.1 m. Use of a microdebrider generated mean aerosol concentrations 18 times above baseline (p = 0.005). High-speed drilling did not produce aerosols greater than baseline. Pituitary tumour resection generated mean aerosol concentrations less than background (p = 0.18). Surgical drape removal generated small and large particles in mean concentrations 6.4 times greater than background (p < 0.001). CONCLUSION: Intubation and extubation generate large amounts of small particles that remain suspended in air for long durations and disperse through theatre. Endonasal access and pituitary tumour resection generate smaller concentrations of larger particles which are airborne for shorter periods and travel shorter distances.


Asunto(s)
Aerosoles/efectos adversos , Endoscopía/efectos adversos , Neoplasias Hipofisarias/cirugía , Extubación Traqueal/efectos adversos , Humanos , Intubación Intratraqueal/efectos adversos , Movimiento (Física) , Exposición Profesional/efectos adversos , Salud Laboral , Quirófanos , Tamaño de la Partícula , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
10.
Sensors (Basel) ; 20(21)2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33120957

RESUMEN

Lysenin is a pore-forming protein extracted from the earthworm Eisenia fetida, which inserts large conductance pores in artificial and natural lipid membranes containing sphingomyelin. Its cytolytic and hemolytic activity is rather indicative of a pore-forming toxin; however, lysenin channels present intricate regulatory features manifested as a reduction in conductance upon exposure to multivalent ions. Lysenin pores also present a large unobstructed channel, which enables the translocation of analytes, such as short DNA and peptide molecules, driven by electrochemical gradients. These important features of lysenin channels provide opportunities for using them as sensors for a large variety of applications. In this respect, this literature review is focused on investigations aimed at the potential use of lysenin channels as analytical tools. The described explorations include interactions with multivalent inorganic and organic cations, analyses on the reversibility of such interactions, insights into the regulation mechanisms of lysenin channels, interactions with purines, stochastic sensing of peptides and DNA molecules, and evidence of molecular translocation. Lysenin channels present themselves as versatile sensing platforms that exploit either intrinsic regulatory features or the changes in ionic currents elicited when molecules thread the conducting pathway, which may be further developed into analytical tools of high specificity and sensitivity or exploited for other scientific biotechnological applications.

11.
Demography ; 57(1): 323-346, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32030626

RESUMEN

In this article, we conduct a comprehensive analysis of the effect of parental involvement (PI) laws on the incidence of abortions to minors in the United States. We contribute to the extant literature in several ways. First, we explore differences in estimates of the effect of PI laws across time that may result from changes in contraception, the composition of pregnant minors, abortion access in nearby states, and differences in how these laws are enforced. We find that PI laws enacted before the mid-1990s are associated with a 15% to 20% reduction in abortions to minors, but PI laws enacted after this time are not associated with declines in abortions to minors. Second, we assess the role of out-of-state travel by minors and find that it is not a significant factor moderating the effect of PI laws. Third, we use a synthetic control approach to explore state-level heterogeneity in the effect of PI laws and find large differences in the effect of PI laws on abortions to minors by state that appear unrelated to the type of PI law or whether contiguous states have enacted PI laws. Finally, we show that estimates of the effect of PI laws using data from either the Centers for Disease Control or the Guttmacher Institute do not differ qualitatively once differences in the states and years available across these data are harmonized.


Asunto(s)
Aborto Inducido/legislación & jurisprudencia , Aborto Inducido/estadística & datos numéricos , Padres , Adolescente , Femenino , Humanos , Estados Unidos
12.
Sci Total Environ ; 690: 426-437, 2019 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-31299575

RESUMEN

The rapid environmental changes in Australia prompt a more thorough investigation of the influence of transportation, local emissions, and optical-chemical properties on aerosol production across the region. A month-long intensive measurement campaign was conducted during spring 2016 at Mission Beach, a remote coastal site west of the Great Barrier Reef (GBR) on the north-east coast of Australia. One aerosol pollution episode was investigated in early October. This event was governed by meteorological conditions and characterized by the increase in black carbon (BC) mass concentration (averaged value of 0.35 ±â€¯0.20 µg m-3). Under the influence of the continental transportation, a new layer of nucleation-mode aerosols with an initial size diameter of 20 nm was observed and aerosol number concentrations reached the peak of 6733 cm-3 at a diameter of 29 nm. The averaged aerosol extinction coefficient at the height of 2 km was 150 Mm-1, with a small depolarized ratio (3.5-5%). Simultaneously, the boundary layer height presented a fall-rise trend in the presence of these enhanced aerosol concentrations and became stable in a later stage of the episode. We did not observe clear boundary layer height diurnal variations from the LiDAR observations or from the Weather Research and Forecasting (WRF) model outputs, except in an earlier stage of the aerosol episode for the former. Although the sea breeze may have been responsible for these particles, on the balance of available data, we suggest that the aerosol properties at the GBR surface during this period are more likely influenced by regional transportation of continental sources, including biomass-burning aerosols.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Arrecifes de Coral , Monitoreo del Ambiente , Australia , Meteorología , Modelos Teóricos , Tiempo (Meteorología)
13.
Evol Med Public Health ; 2019(1): 169-180, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31890209

RESUMEN

BACKGROUND AND OBJECTIVES: Metallic antimicrobial materials are of growing interest due to their potential to control pathogenic and multidrug-resistant bacteria. Yet we do not know if utilizing these materials can lead to genetic adaptations that produce even more dangerous bacterial varieties. METHODOLOGY: Here we utilize experimental evolution to produce strains of Escherichia coli K-12 MG1655 resistant to, the iron analog, gallium nitrate (Ga(NO3)3). Whole genome sequencing was utilized to determine genomic changes associated with gallium resistance. Computational modeling was utilized to propose potential molecular mechanisms of resistance. RESULTS: By day 10 of evolution, increased gallium resistance was evident in populations cultured in medium containing a sublethal concentration of gallium. Furthermore, these populations showed increased resistance to ionic silver and iron (III), but not iron (II) and no increase in traditional antibiotic resistance compared with controls and the ancestral strain. In contrast, the control populations showed increased resistance to rifampicin relative to the gallium-resistant and ancestral population. Genomic analysis identified hard selective sweeps of mutations in several genes in the gallium (III)-resistant lines including: fecA (iron citrate outer membrane transporter), insl1 (IS30 tranposase) one intergenic mutations arsC →/→ yhiS; (arsenate reductase/pseudogene) and in one pseudogene yedN ←; (iapH/yopM family). Two additional significant intergenic polymorphisms were found at frequencies > 0.500 in fepD ←/→ entS (iron-enterobactin transporter subunit/enterobactin exporter, iron-regulated) and yfgF ←/→ yfgG (cyclic-di-GMP phosphodiesterase, anaerobic/uncharacterized protein). The control populations displayed mutations in the rpoB gene, a gene associated with rifampicin resistance. CONCLUSIONS: This study corroborates recent results observed in experiments utilizing pathogenic Pseudomonas strains that also showed that Gram-negative bacteria can rapidly evolve resistance to an atom that mimics an essential micronutrient and shows the pleiotropic consequences associated with this adaptation. LAY SUMMARY: We utilize experimental evolution to produce strains of Escherichia coli K-12 MG1655 resistant to, the iron analog, gallium nitrate (Ga(NO3)3). Whole genome sequencing was utilized to determine genomic changes associated with gallium resistance. Computational modeling was utilized to propose potential molecular mechanisms of resistance.

14.
Mol Ther Methods Clin Dev ; 12: 71-84, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30534580

RESUMEN

Adeno-associated virus (AAV) vectors have become one of the most widely used gene transfer tools in human gene therapy. Considerable effort is currently being focused on AAV capsid engineering strategies with the aim of developing novel variants with enhanced tropism for specific human cell types, decreased human seroreactivity, and increased manufacturability. Selection strategies based on directed evolution rely on the generation of highly variable AAV capsid libraries using methods such as DNA-family shuffling, a technique reliant on stretches of high DNA sequence identity between input parental capsid sequences. This identity dependence for reassembly of shuffled capsids is inherently limiting and results in decreased shuffling efficiency as the phylogenetic distance between parental AAV capsids increases. To overcome this limitation, we have developed a novel codon-optimization algorithm that exploits evolutionarily defined codon usage at each amino acid residue in the parental sequences. This method increases average sequence identity between capsids, while enhancing the probability of retaining capsid functionality, and facilitates incorporation of phylogenetically distant serotypes into the DNA-shuffled libraries. This technology will help accelerate the discovery of an increasingly powerful repertoire of AAV capsid variants for cell-type and disease-specific applications.

15.
Med Teach ; 41(4): 457-464, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30451051

RESUMEN

Introduction: ASPIRE Excellence Awards in Student Assessment are offered to medical schools with innovative and comprehensive assessment programmes adjudged by international experts, using evidence-based criteria. The journeys of three ASPIRE-winning medical schools toward "assessment excellence" are presented. These schools include Aga Khan University Medical College (AKU-MC), Pakistan, Southern Illinois University School of Medicine (SIUSOM), USA, and University of Leeds School of Medicine, UK. Methods: The unfolding journeys highlighting achievements, innovations, and essential components of each assessment programme were compared to identify differences and commonalities. Results: Cultural contextual differences included developed-versus-developing country, east-west, type of regulatory bodies, and institutional-versus-national certifying/licensing examinations, which influence curricula and assessments. In all, 12 essential commonalities were found: alignment with institutional vision; sustained assessment leadership; stakeholder engagement; communication between curriculum and assessment; assessment-for-learning and feedback; longitudinal student profiling of outcome achievement; assessment rigor and robustness; 360° feedback from-and-to assessment; continuous enrichment through rigorous quality assurance; societal sensitivity; influencing others; and a "wow factor." Conclusions: Although the journeys of the three medical schools were undertaken in different cultural contexts, similar core components highlight strong foundations in student assessment. The journeys continue as assessment programmes remain dynamic and measurement science expands. This article may be helpful to other institutions pursuing excellence in assessment.


Asunto(s)
Evaluación Educacional/métodos , Evaluación Educacional/normas , Aprendizaje , Facultades de Medicina/organización & administración , Distinciones y Premios , Comunicación , Curriculum , Países Desarrollados , Países en Desarrollo , Retroalimentación Formativa , Humanos , Liderazgo , Innovación Organizacional , Facultades de Medicina/normas
16.
Front Plant Sci ; 9: 1025, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30083174

RESUMEN

Soybean (Glycine max) is an important food stock, and also considered an allergenic food with at least eight well characterized allergens. However, it is a less prevalent allergen source than many other foods and is rarely life-threatening. Soybean is incorporated into commonly consumed foods, and therefore, the allergens pose a potential concern for individuals already sensitized. The protein profile of soybean can be affected by several factors including genetic and environmental. To investigate how soybean allergen content may be affected by genetics and/or environment, nine soy allergens were quantified from three commercial soybean varieties grown at nine locations in three states within a single climate zone in North America; Iowa, Illinois, and Indiana, United States. Quantitation was achieved using liquid chromatography-selected reaction monitoring (LC-SRM) tandem mass spectrometry with AQUA peptide standards specific to the nine target allergens. Quantitation of allergen concentration indicated that both genetics and location affected specific allergen content. Seven of the nine allergens were significantly influenced by genetics, with the exceptions of glycinin G4 and KTI 3. The allergens P34, Gly m Bd 28k, glycinin G3, and KTI 1 showed statistically significant impact from location as well, but at a lower threshold of significance compared with genetics (cultivar/variety). This dataset contributes to our understanding of the natural variation of endogenous allergens, as it represents a sampling of soybeans grown in a controlled, distributed plot design under agronomic conditions common for commercial soybean food and feed production. The aim was to build upon our recent understanding of how allergens are expressed as part of the overall soybean proteome.

17.
PLoS One ; 12(2): e0171926, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28207780

RESUMEN

The susceptibility of a dietary protein to proteolytic degradation by digestive enzymes, such as gastric pepsin, provides information on the likelihood of systemic exposure to a structurally intact and biologically active macromolecule, thus informing on the safety of proteins for human and animal consumption. Therefore, the purpose of standardized in vitro degradation studies that are performed during protein safety assessments is to distinguish whether proteins of interest are susceptible or resistant to pepsin degradation via a study design that enables study-to-study comparison. Attempting to assess pepsin degradation under a wide-range of possible physiological conditions poses a problem because of the lack of robust and consistent data collected under a large-range of sub-optimal conditions, which undermines the needs to harmonize in vitro degradation conditions. This report systematically compares the effects of pH, incubation time, and pepsin-to-substrate protein ratio on the relative degradation of five dietary proteins: three pepsin susceptible proteins [ribulose 1,5-bisphosphate carboxylase-oxygenase (Rubisco), horseradish peroxidase (HRP), hemoglobin (Hb)], and two pepsin resistant proteins [lipid transfer protein (LTP) and soybean trypsin inhibitor (STI)]. The results indicate that proteins susceptible to pepsin degradation are readily distinguishable from pepsin-resistant proteins when the reaction conditions are within the well-characterized optima for pepsin. The current standardized in vitro pepsin resistant assay with low pH and high pepsin-to-substrate ratio fits this purpose. Using non-optimal pH and/or pepsin-to-substrate protein ratios resulted in susceptible proteins no longer being reliably degraded by this stomach enzyme, which compromises the ability of this in vitro assay to distinguish between resistant and susceptible proteins and, therefore, no longer providing useful data to an overall weight-of-evidence approach to assessing safety of proteins.


Asunto(s)
Proteínas en la Dieta/química , Inocuidad de los Alimentos , Pepsina A/química , Proteínas en la Dieta/inmunología , Concentración de Iones de Hidrógeno , Factores de Tiempo
18.
J Agric Food Chem ; 65(8): 1740-1749, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28161956

RESUMEN

Lipid transfer protein (LTP) is the main causative agent for rare food allergic reactions to maize. This paper describes a new, validated ELISA that accurately measures maize LTP concentrations from 0.2 to 6.4 ng/mL. The levels of LTP ranged from 171 to 865 µg/g of grain, a 5.1-fold difference, across a set of 49 samples of maize B73 hybrids derived from the Nested Association Mapping (NAM) founder lines and a diverse collection of landrace accessions from North and South America. A second set of 107 unique samples from 18 commercial hybrids grown over two years across 10 U.S. states showed a comparable range of LTP level (212-751 µg/g of grain). Statistical analysis showed that genetic and environmental factors contributed 63 and 6%, respectively, to the variance in LTP levels. Therefore, the natural variation of maize LTP is up to 5-fold different across a diverse collection of varieties that have a history of safe cultivation and consumption.


Asunto(s)
Proteínas Portadoras/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Proteínas de Plantas/análisis , Zea mays/química , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Proteínas de Plantas/genética , Proteínas de Plantas/inmunología , Zea mays/genética , Zea mays/inmunología
19.
J Agric Food Chem ; 65(2): 463-472, 2017 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-27997188

RESUMEN

Soybean (Glycine max L. Merrill) is one of eight major allergenic foods with endogenous proteins identified as allergens. To better understand the natural variability of five soybean allergens (Gly m 4, Gly m 5, Gly m 6, Gly m Bd 28k, and Gly m Bd 30k), validated enzyme-linked immunosorbent assays (ELISAs) were developed. These ELISAs measured allergens in 604 soybean samples collected from locations in North and South America over five growing seasons (2009-2013/2014) and including 37 conventional varieties. Levels of these five allergens varied 5-19-fold. Multivariate statistical analyses and pairwise comparisons show that environmental factors have a larger effect on allergen levels than genetic factors. Therefore, from year to year, consumers are exposed to highly variable levels of allergens in soy-based foods, bringing into question whether quantitative comparison of endogenous allergen levels of new genetically modified soybean adds meaningful information to their overall safety risk assessment.


Asunto(s)
Alérgenos/análisis , Glycine max/química , Proteínas de Soja/análisis , Antígenos de Plantas/análisis , Antígenos de Plantas/inmunología , Ensayo de Inmunoadsorción Enzimática , Hipersensibilidad a los Alimentos , Variación Genética , Globulinas/análisis , Globulinas/inmunología , Glicoproteínas , Análisis Multivariante , América del Norte , Reproducibilidad de los Resultados , Proteínas de Almacenamiento de Semillas/análisis , Proteínas de Almacenamiento de Semillas/inmunología , Semillas/química , América del Sur , Proteínas de Soja/genética , Proteínas de Soja/inmunología , Glycine max/genética , Glycine max/inmunología
20.
J Orthop Sports Phys Ther ; 46(9): 726-41, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27477253

RESUMEN

Study Design Retrospective cohort. Background Patient-classification subgroupings may be important prognostic factors explaining outcomes. Objectives To determine effects of adding classification variables (McKenzie syndrome and pain patterns, including centralization and directional preference; Symptom Checklist Back Pain Prediction Model [SCL BPPM]; and the Fear-Avoidance Beliefs Questionnaire subscales of work and physical activity) to a baseline risk-adjusted model predicting functional status (FS) outcomes. Methods Consecutive patients completed a battery of questionnaires that gathered information on 11 risk-adjustment variables. Physical therapists trained in Mechanical Diagnosis and Therapy methods classified each patient by McKenzie syndromes and pain pattern. Functional status was assessed at discharge by patient-reported outcomes. Only patients with complete data were included. Risk of selection bias was assessed. Prediction of discharge FS was assessed using linear stepwise regression models, allowing 13 variables to enter the model. Significant variables were retained in subsequent models. Model power (R(2)) and beta coefficients for model variables were estimated. Results Two thousand sixty-six patients with lumbar impairments were evaluated. Of those, 994 (48%), 10 (<1%), and 601 (29%) were excluded due to incomplete psychosocial data, McKenzie classification data, and missing FS at discharge, respectively. The final sample for analyses was 723 (35%). Overall R(2) for the baseline prediction FS model was 0.40. Adding classification variables to the baseline model did not result in significant increases in R(2). McKenzie syndrome or pain pattern explained 2.8% and 3.0% of the variance, respectively. When pain pattern and SCL BPPM were added simultaneously, overall model R(2) increased to 0.44. Although none of these increases in R(2) were significant, some classification variables were stronger predictors compared with some other variables included in the baseline model. Conclusion The small added prognostic capabilities identified when combining McKenzie or pain-pattern classifications with the SCL BPPM classification did not significantly improve prediction of FS outcomes in this study. Additional research is warranted to investigate the importance of classification variables compared with those used in the baseline model to maximize predictive power. Level of Evidence Prognosis, level 4. J Orthop Sports Phys Ther 2016;46(9):726-741. Epub 31 Jul 2016. doi:10.2519/jospt.2016.6266.


Asunto(s)
Dolor de la Región Lumbar/clasificación , Modelos Teóricos , Modalidades de Fisioterapia , Ajuste de Riesgo/estadística & datos numéricos , Enfermedades de la Columna Vertebral/clasificación , Adolescente , Adulto , Factores de Edad , Anciano , Terapia por Ejercicio/psicología , Miedo , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Funciones de Verosimilitud , Modelos Logísticos , Dolor de la Región Lumbar/psicología , Masculino , Persona de Mediana Edad , Dimensión del Dolor/psicología , Estudios Retrospectivos , Ajuste de Riesgo/clasificación , Enfermedades de la Columna Vertebral/psicología , Encuestas y Cuestionarios , Evaluación de Síntomas/métodos , Síndrome , Resultado del Tratamiento , Adulto Joven
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