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1.
Fetal Diagn Ther ; : 1-33, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39380464

RESUMEN

INTRODUCTION: The United States has the poorest health statistics of any high-income country. Political polarization has risen dramatically; newer safety net programs (the Affordable Care Act [ACA]) are unevenly provided because many Republican-leaning states refused expanded Federal coverage. Democratic programs have reduced physician leadership of medicine. Both have been deleterious. Here, we investigated associations among four key health measures two of which directly impact pregnancy outcomes and two that affect all patients by percentage of each state that voted for the Republican versus Democratic candidate in the 2020 presidential election. METHODS: For each state, we used public, non-partisan databases to assess the incidence of COVID, maternal, and infant mortality per 100,000 population and average life expectancy. Correlations among these four outcome variables and percentage Republican vote were calculated (r), contextualized by measuring associations with related variables including COVID vaccination rates, access to medical care, and incidences of heart disease, obesity, diabetes, gunshot deaths, and automotive fatalities. RESULTS: COVID mortality, maternal and infant mortality, and life expectancy were highly correlated with percentage Republican ("red") vote per state. If "red" states had vaccination rates equivalent to Democratic-leaning ("blue") states, 72,000 deaths could have been avoided. Overall, "red" states have lower health metrics, reduced access to care, and higher comorbidities. CONCLUSION: The percent Republican vote was strongly associated, but not the whole answer, for worse health outcomes for multiple key measures of public health including mortality, access to care, and various comorbidities. Overall, the ACA has improved patient access to care but has also led to "maternity care deserts" disproportionately in rural areas in "red" states. Translating insurance coverage into improved care and outcomes requires further analysis and will require multi-pronged approaches including expanding coverage and incentivizing quality care.

2.
Am J Obstet Gynecol ; 228(5S): S1129-S1143, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37164491

RESUMEN

Electronic fetal monitoring, particularly in the form of cardiotocography, forms the centerpiece of labor management. Initially successfully designed for stillbirth prevention, there was hope to also include prediction and prevention of fetal acidosis and its sequelae. With the routine use of electronic fetal monitoring, the cesarean delivery rate increased from <5% in the 1970s to >30% at present. Most at-risk cases produced healthy babies, resulting in part from considerable confusion as to the differences between diagnostic and screening tests. Electronic fetal monitoring is clearly a screening test. Multiple attempts have aimed at enhancing its ability to accurately distinguish babies at risk of in utero injury from those who are not and to do this in a timely manner so that appropriate intervention can be performed. Even key electronic fetal monitoring opinion leaders admit that this goal has yet to be achieved. Our group has developed a modified approach called the "Fetal Reserve Index" that contextualizes the findings of electronic fetal monitoring by formally including the presence of maternal, fetal, and obstetrical risk factors and increased uterine contraction frequencies and breaking up the tracing into 4 quantifiable components (heart rate, variability, decelerations, and accelerations). The result is a quantitative 8-point metric, with each variable being weighted equally in version 1.0. In multiple previously published refereed papers, we have shown that in head-to-head studies comparing the fetal reserve index with the American College of Obstetricians and Gynecologists' fetal heart rate categories, the fetal reserve index more accurately identifies babies born with cerebral palsy and could also reduce the rates of emergency cesarean delivery and vaginal operative deliveries. We found that the fetal reserve index scores and fetal pH and base excess actually begin to fall earlier in the first stage of labor than was commonly appreciated, and the fetal reserve index provides a good surrogate for pH and base excess values. Finally, the last fetal reserve index score before delivery combined with early analysis of neonatal heart rate and acid/base balance shows that the period of risk for neonatal neurologic impairment can continue for the first 30 minutes of life and requires much closer neonatal observation than is currently being done.


Asunto(s)
Cardiotocografía , Trabajo de Parto , Recién Nacido , Femenino , Embarazo , Humanos , Cardiotocografía/métodos , Parto Obstétrico/métodos , Cesárea , Atención Prenatal , Frecuencia Cardíaca Fetal/fisiología , Monitoreo Fetal
3.
Bioprocess Biosyst Eng ; 45(1): 217-226, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34657162

RESUMEN

Polypropylene was modified to contain chitosan and evaluate its ability to generate Lactobacillus casei biofilms and their lactic acid production. Biofilm formation was carried out in either rich or minimal media. The chitosan-modified polypropylene harbored ~ 37% more cells than the control polypropylene. The biofilms from the chitosan-modified polypropylene grown in rich medium produced ~ 2 times more lactic acid after 72 h of incubation than the control suspended cells. There was no significant difference in the production of lactic acid after 72 h by L. casei biofilms on the chitosan-modified polypropylene grown in minimal media as compared with cells in suspension after 48 h and 72 h of incubation. Infrared spectroscopy confirmed higher deposition of nutrients and biomass on the chitosan-modified polypropylene as compared to the chitosan-free polypropylene. Electron and atomic force microscopy confirmed thicker biofilms when rich media were used to grow them as compared to minimal medium.


Asunto(s)
Ácido Láctico/metabolismo , Lactobacillus/metabolismo , Biopelículas
4.
Environ Sci Technol ; 55(20): 13541-13550, 2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34009961

RESUMEN

Strategies to reduce crop losses due to drought are needed as climate variability affects agricultural productivity. Wheat (Triticum aestivum var. Juniper) growth in a nutrient-sufficient, solid growth matrix containing varied doses of CuO, ZnO, and SiO2 nanoparticles (NPs) was used to evaluate NP mitigation of drought stress. NP amendments were at fertilizer levels, with maxima of 30 Cu, 20 Zn, and 200 Si (mg metal/kg matrix). Seeds of this drought-tolerant cultivar were inoculated with Pseudomonas chlororaphis O6 (PcO6) to provide a protective root microbiome. An 8 day drought imposed on 14 day-old wheat seedlings decreased shoot and root mass, shoot water content, and the quantum yield of photosystem II when compared to watered plants. PcO6 root colonization was not impaired by drought or NPs. A dose-dependent increase in the Cu, Zn, and Si from the NPs was observed from analysis of the rhizosphere solution, and this process was not affected by drought. Consequently, fertilizer concentrations of the NPs did not further improve drought tolerance in wheat seedlings under the growth conditions of adequate mineral nutrition and the presence of a beneficial microbiome. These findings suggest that potential NP benefits in promoting plant drought tolerance occur only under certain environmental conditions.


Asunto(s)
Nanopartículas , Óxido de Zinc , Sequías , Nutrientes , Raíces de Plantas , Plantones , Dióxido de Silicio , Triticum
5.
Fetal Diagn Ther ; 46(3): 159-165, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30463080

RESUMEN

Electronic fetal monitoring (EFM) is a poor predictor of outcomes attributable to delivery problems. Contextualizing EFM by adding maternal, obstetrical, and fetal risk-related information to create an index called the Fetal Reserve Index (FRI) improves the predictive capacity and facilitates the timing of interventions. Here, we test critical assumptions of FRI as a clinical tool. Our conceptualization implies that the earlier one reaches the red zone (FRI ≤25) and the longer one spends in the red zone, the greater the likelihood of emergency operative deliveries (EOD). METHODS: We analyzed 1,402 patients using logistic regression predicting the probability of EOD and employed qualitative methodology techniques to refine predictive capabilities. RESULTS: Reaching the red zone early and staying there > 1 h increases the probability of EOD. When these risk factors are paired with intrauterine resuscitation (IR) in Stage 1, the reduction of EOD is substantial. CONCLUSION: FRI is a capable predictor of EOD because it accurately identifies the level of malleable risk. FRI analysis increases the risk of using IR in Stage 1. Matching risk and resources dramatically reduces the chances of EOD. Earlier IR improves the outcomes if the calculated risk is high.


Asunto(s)
Cardiotocografía , Parálisis Cerebral/prevención & control , Cesárea , Parto Obstétrico/métodos , Adulto , Femenino , Sufrimiento Fetal , Frecuencia Cardíaca Fetal , Humanos , Recién Nacido , Embarazo , Factores de Riesgo
6.
Molecules ; 24(16)2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31412646

RESUMEN

Organosilanes (e.g., R'-SiOR3) provide hydrophobic functionality in thin-film coatings, porous gels, and particles. Compared with tetraalkoxysilanes (SiOR4), organosilanes exhibit distinct reaction kinetics and assembly mechanisms arising from steric and electronic properties of the R' group on the silicon atom. Here, the hydrolysis and condensation pathways of n-propyltrimethoxy silane (nPM) and a tri-fluorinated analog of nPM, 3,3,3-trifluoropropyl trimethoxy silane (3F), were investigated under aqueous conditions at pH 1.7, 2.0, 3.0, and 4.0. Prior to hydrolysis, 3F and nPM are insoluble in water and form a lens at the bottom (3F) or top (nPM) of the solutions. This phase separation was employed to follow reaction kinetics using a Turbiscan instrument to monitor hydrolysis through solubilization of the neat silane lens while simultaneously tracking condensation-induced turbidity throughout the bulk solution. Dynamic light scattering confirmed the silane condensation and particle aggregation processes reported by the turbidity scanning. Employing macroscopic phase separation of the starting reactants from the solvent further allows for control over the reaction kinetics, as the interfacial area can be readily controlled by reaction vessel geometry, namely by controlling the surface area to volume. In-situ turbidity scanning and dynamic light scattering revealed distinct reaction kinetics for nPM and 3F, attributable to the electron withdrawing and donating nature of the fluoro- and organo-side chains of 3F and nPM, respectively.


Asunto(s)
Dispersión Dinámica de Luz , Geles/química , Transición de Fase , Silanos/química , Soluciones/química , Fenómenos Químicos , Dispersión Dinámica de Luz/métodos , Concentración de Iones de Hidrógeno , Hidrólisis , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Nanopartículas/química
7.
Molecules ; 24(14)2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31295838

RESUMEN

This study introduces a simple and environmentally friendly method to synthesize silica-protein nanocomposite materials using microwave energy to solubilize hydrophobic protein in an aqueous solution of pre-hydrolyzed organo- or fluoro-silane. Sol-gel functionality can be enhanced through biomacromolecule incorporation to tune mechanical properties, surface energy, and biocompatibility. Here, synthetic spider silk protein and organo- and fluoro-silane precursors were dissolved and mixed in weakly acidic aqueous solution using microwave technology. Scanning electron microscopy (SEM) and Atomic force microscopy (AFM) images revealed the formation of spherical nanoparticles with sizes ranging from 100 to 500 nm depending, in part, on silane fluoro- or organo-side chain chemistry. The silane-protein interaction in the nanocomposite was assessed through infrared spectroscopy. Deconvoluted ATR-FTIR (Attenuated total reflectance Fourier-transform infrared spectroscopy) spectra revealed silane chemistry-specific conformational changes in the protein-silane nanocomposites. Relative to microwave-solubilized spider silk protein, the ß structure content increased by 14% in the spider silk-organo-silica nanocomposites, but decreased by a net 20% in the spider silk-fluoro-silica nanocomposites. Methods of tuning the secondary structures, and in particular ß-sheets that are the cross-linking moieties in spider silks and other self-assembling fibrillar proteins, may provide a unique means to promote protein interactions, favor subsequent epitaxial growth process, and enhance the properties of the protein-silane nanocomposites.


Asunto(s)
Microondas , Nanocompuestos/química , Dióxido de Silicio/química , Geles de Silicona/química , Seda/química , Arañas/química , Animales , Microscopía de Fuerza Atómica , Nanocompuestos/ultraestructura , Geles de Silicona/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier
9.
Biometals ; 29(2): 211-23, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26805711

RESUMEN

Cost-effective "green" methods of producing Ag nanoparticles (NPs) are being examined because of the potential of these NPs as antimicrobials. Ag NPs were generated from Ag ions using extracellular metabolites from a soil-borne Pythium species. The NPs were variable in size, but had one dimension less than 50 nm and were biocoated; aggregation and coating changed with acetone precipitation. They had dose-dependent lethal effects on a soil pseudomonad, Pseudomonas chlororaphis O6, and were about 30-fold more effective than Ag(+) ions. A role of reactive oxygen species in cell death was demonstrated by use of fluorescent dyes responsive to superoxide anion and peroxide accumulation. Also mutants of the pseudomonad, defective in enzymes that protect against oxidative stress, were more sensitive than the wild type strain; mutant sensitivity differed between exposure to Ag NPs and Ag(+) ions demonstrating a nano-effect. Imaging of bacterial cells treated with the biocoated Ag NPs revealed no cell lysis, but there were changes in surface properties and cell height. These findings support that biocoating the NPs results in limited Ag release and yet they retained potent antimicrobial activity.


Asunto(s)
Antiinfecciosos/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Antiinfecciosos/química , Reactores Biológicos , Peróxido de Hidrógeno/farmacología , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Pseudomonas chlororaphis/efectos de los fármacos , Pseudomonas chlororaphis/ultraestructura , Pythium/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plata/química
10.
Biometals ; 28(1): 101-12, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25351960

RESUMEN

Zn is an essential element for plants yet some soils are Zn-deficient and/or have low Zn-bioavailability. This paper addresses the feasibility of using ZnO nanoparticles (NPs) as soil amendments to improve Zn levels in the plant. The effects of soil properties on phytotoxicity and Zn bioavailability from the NPs were studied by using an acidic and a calcareous alkaline soil. In the acid soil, the ZnO NPs caused dose-dependent phytotoxicity, observed as inhibition of elongation of roots of wheat, Triticum aestivum. Phytotoxicity was mitigated in the calcareous alkaline soil although uptake of Zn from the ZnO NPs occurred doubling the Zn level compared to control plants. This increase occurred with a low level of Zn in the soil solution as expected from the interactions of Zn with the soil components at the alkaline pH. Soluble Zn in the acid soil was 200-fold higher and shoot levels were tenfold higher than from the alkaline soil correlating with phytotoxicity. Mitigation of toxicity was not observed in plants grown in sand amended with a commercial preparation of humic acid: growth, shoot uptake and solubility of Zn from the NPs was not altered by the humic acid. Thus, variation in humic acid between soils may not be a major factor influencing plant responses to the NPs. These findings illustrate that formulations of ZnO NPs to be used as a soil amendment would need to be tuned to soil properties to avoid phytotoxicity yet provide increased Zn accumulations in the plant.


Asunto(s)
Nanopartículas/química , Nanopartículas/toxicidad , Triticum/efectos de los fármacos , Óxido de Zinc/química , Óxido de Zinc/toxicidad , Raíces de Plantas/efectos de los fármacos , Brotes de la Planta/efectos de los fármacos , Suelo
11.
Ecotoxicology ; 24(1): 119-29, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25297564

RESUMEN

The expansion of nanotechnology raises concerns about the consequences of nanomaterials in plants. Here, the effects of nanoparticles (NPs; 100-500 mg/kg) on processes related to micronutrient accumulation were evaluated in bean (Phaseolus vulgaris) exposed to CuO NPs, a mixture of CuO and ZnO (CuO:ZnO) NPs, and in CuO NP-exposed plants colonized by a root bacterium, Pseudomonas chlororaphis O6 (PcO6) in a sand matrix for 7 days. Depending on exposure levels, the inhibition of growth by CuO NPs was more apparent in roots (10-66 %) than shoots (9-25 %). In contrast, CuO:ZnO NPs or root colonization with PcO6 partially mitigated growth inhibition. At 500 mg/kg exposure, CuO NPs increased soluble Cu in the growth matrix by 23-fold, relative to the control, while CuO:ZnO NPs increased soluble Cu (26-fold), Zn (127-fold) and Ca (4.5-fold), but reduced levels of Fe (0.8-fold) and Mn (0.75-fold). Shoot accumulations of Cu (3.8-fold) and Na (1-fold) increased, while those of Fe (0.4-fold), Mn (0.2-fold), Zn (0.5-fold) and Ca (0.5-fold) were reduced with CuO NP (500 mg/kg) exposure. CuO:ZnO NPs also increased shoot Cu, Zn and Na levels, while decreasing that of Fe, Mn, Ca and Mg. Root colonization reduced shoot uptake of Cu and Na, 15 and 24 %, respectively. CuO NPs inhibited ferric reductase (up to 49 %) but stimulated cupric (up to 273 %) reductase activity; while CuO:ZnO NPs or root colonization by PcO6 altered levels of ferric, but not copper reductase activity, relative to CuO NPs. Cu ions at the level released from the NPs did not duplicate these effects. Our findings demonstrate that in addition to the apparent phytotoxic effects of NPs, NP exposure may also have subtle impacts on secondary processes such as metal nutrition.


Asunto(s)
Cobre/toxicidad , Nanopartículas del Metal/toxicidad , Phaseolus/efectos de los fármacos , Microbiología del Suelo , Óxido de Zinc/toxicidad , Metales/metabolismo , Phaseolus/metabolismo , Phaseolus/microbiología , Pseudomonas/crecimiento & desarrollo
12.
Fetal Diagn Ther ; 35(2): 69-82, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24525884

RESUMEN

Fetal reduction (FR) began in the 1980s to salvage the pregnancies of couples needing fertility therapy who were finally successful but with too many fetuses. Since then, it has gone from a rarity performed in only the highest risk situations to an integral fail-safe of infertility practice. Our understanding of the problems of multiple and premature births has increased - even twins carry 4-5 times more risk than singletons. Evaluation of fetuses before FR has permitted more intelligent choices and improved resultant outcomes. We now perform chorionic villus sampling in approximately 85% of cases, obtain fluorescent in situ hybridization (FISH) results overnight, and then perform FR the next day. Decisions about which to reduce prioritize anomalies, but now can include fetal gender in the decision process, as couples are now just as likely to want girls as boys. In Mendelian cases, sophisticated molecular analyses permit diagnoses before FR, and new uses such as paternity analysis can be performed. Ethical arguments have also evolved; as with many technologies in which the start was for only 'life or death cases', FR has also moved into 'quality of life' issues. FR of twins to a singleton now compromise about 30% of our cases.


Asunto(s)
Complicaciones del Embarazo/prevención & control , Reducción de Embarazo Multifetal/historia , Femenino , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Embarazo , Resultado del Embarazo , Reducción de Embarazo Multifetal/ética , Embarazo Múltiple , Transferencia de un Solo Embrión
13.
Reprod Sci ; 31(5): 1179-1189, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38133768

RESUMEN

Cerebral palsy (CP) has been recognized as a group of neurologic disorders with varying etiologies and ontogenies. While a percentage of CP cases arises during labor, the expanded use of electronic fetal monitoring (EFM) to include prevention of CP has resulted in decades of vastly increased interventions that have not significantly reduced the incidence of CP for infants born at term in the USA. Litigation alleging that poor obstetrical practice caused CP in most of these affected children has led to contentious arguments regarding the actual etiologies of this condition and often resulted in substantial monetary awards for plaintiffs. Recent advances in genetic testing using whole exome sequencing have revealed that at least one-third of CP cases in term infants are genetic in origin and therefore not labor-related. Here, we will present and discuss previous attempts to sort out contributing etiologies and ontogenies of CP, and how these newer diagnostic techniques are rapidly improving our ability to better detect and understand such cases. In light of these developments, we present our vision for an overarching spectrum for proper categorization of CP cases into that the following groups: (1) those begun at conception from genetic causes (nonpreventable); (2) those stemming from adverse antenatal/pre-labor events (possibly preventable with heightened antepartum assessment); (3) Those arising from intrapartum events (potentially preventable by earlier interventions); (4) Those occurring shortly after birth (possibly preventable with closer neonatal monitoring); (5) Those that appear later in the postnatal period from non-labor-related causes such as untreated infections or postnatal intracranial hemorrhages.


Asunto(s)
Parálisis Cerebral , Humanos , Parálisis Cerebral/etiología , Parálisis Cerebral/diagnóstico , Parálisis Cerebral/epidemiología , Parálisis Cerebral/prevención & control , Parálisis Cerebral/genética , Embarazo , Femenino , Recién Nacido
14.
Environ Sci Technol ; 47(2): 1082-90, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23259709

RESUMEN

Hydroponic plant growth studies indicate that silver nanoparticles (Ag NPs) are phytotoxic. In this work, the phytotoxicity of commercial Ag NPs (10 nm) was evaluated in a sand growth matrix. Both NPs and soluble Ag were recovered from water extracts of the sand after growth of plants challenged with the commercial product; the surface charge of the Ag NPs in this extract was slightly reduced compared to the stock NPs. The Ag NPs reduced the length of shoots and roots of wheat in a dose-dependent manner. Furthermore, 2.5 mg/kg of the NPs increased branching in the roots of wheat (Triticum aestivum L.), thereby affecting plant biomass. Micron-sized (bulk) Ag particles (2.5 mg/kg) as well as Ag ions (63 µg Ag/kg) equivalent to the amount of soluble Ag in planted sand with Ag NPs (2.5 mg/kg) did not affect plant growth compared to control. In contrast, higher levels of Ag ions (2.5 mg/kg) reduced plant growth to a similar extent as the Ag NPs. Accumulation of Ag was detected in the shoots, indicating an uptake and transport of the metal from the Ag NPs in the sand. Transmision electron microscopy indicated that Ag NPs were present in shoots of plants with roots exposed to the Ag NPs or high levels of Ag ions. Both of these treatments caused oxidative stress in roots, as indicated by accumulation of oxidized glutathione, and induced expression of a gene encoding a metallothionein involved in detoxification by metal ion sequestration. Our findings demonstrate the potential effects of environmental contamination by Ag NPs on the metabolism and growth of food crops in a solid matrix.


Asunto(s)
Nanopartículas del Metal/toxicidad , Plata/toxicidad , Triticum/efectos de los fármacos , Triticum/crecimiento & desarrollo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/crecimiento & desarrollo , Dióxido de Silicio/química
15.
Environ Sci Technol ; 47(9): 4734-42, 2013 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-23540424

RESUMEN

The environmental fate of metal oxide particles as a function of size was assessed by comparing the behavior of CuO or ZnO nanoparticles (NPs) to that of the corresponding microparticles (MPs) in a sand matrix, with and without wheat (Triticum aestivum L.) growth. After 14 days of incubation in the planted sand, the CuO and ZnO NPs were increased from their nominal sizes of <50 nm and <100 nm, to ~317 nm and ~483 nm, respectively. Accordingly, the negative surface charge of colloids present in aqueous extracts from the sand amended with CuO (-27.0 mV) and ZnO (-10.0 mV) NPs was reduced by the presence of plants, to -19.8 mV and -6.0 mV, respectively. The surface charge of the MPs was not influenced by plants. Plant growth increased dissolution of NPs and MPs of both metal oxides in the sand from <0.3 mg/kg to about 1.0 mg/kg for the CuO products, and from ≤0.6 mg/kg to between 1.0 and 2.2 mg/kg for the Zn products. The NP or MP products reduced wheat root length by ~60% or ~50% from control levels; CuO was more toxic than ZnO. X-ray absorption spectroscopy (XAS) analysis showed that treatments with MPs or NPs of ZnO led to similar accumulations of Zn-phosphate species in the shoots, likely from dissolution of ZnO. Exposure to CuO NPs or MPs resulted in similar XAS spectra for Cu in the shoots explained by plant accumulation of both CuO and Cu(I)-sulfur complexes. These findings demonstrate the similarities between commercial NPs and MPs of CuO or ZnO in wheat plants, with greater root toxicity correlating with smaller particle size. Factors from the sand and the plant modified the aggregation or dissolution of both types of particles, thus, influencing their environmental fates.


Asunto(s)
Cobre/química , Nanopartículas , Plantas/química , Óxido de Zinc/química , Microscopía de Fuerza Atómica , Solubilidad , Espectroscopía de Absorción de Rayos X
16.
Biometals ; 26(6): 913-24, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23933719

RESUMEN

Fungal plant pathogens such as Fusarium graminearum cause severe global economic losses in cereals crops, and current control measures are limited. This work addresses the potential for ZnO nanoparticles (NPs) and biocontrol bacteria to be used in plant fungal control strategies. Growth of F. graminearum was significantly (p = 0.05) inhibited by inclusion of the NPs in a mung bean broth agar and in sand. Suspension in mung bean broth medium modified the surface charge, dissolution, and aggregation state of the ZnO NPs, in comparison to processes occurring in water suspension. The ZnO NPs were significantly more inhibitory to fungal growth than micro-sized particles of ZnO, although both types of particles released similar levels of soluble Zn, indicating size-dependent toxicity of the particles. Zn ions produced dose-dependent inhibition, noticeable at the level of soluble Zn released from NPs after seven-day suspension in medium; inhibitory levels caused acidification of the growth medium. Transfer of fungal inoculum after exposure to the ZnO NPs to fresh medium did not indicate adaptation to the stress because growth was still inhibited by the NPs. The ZnO NPs did not prevent metabolites from a biocontrol bacterium, Pseudomonas chlororaphis O6, from inhibiting Fusarium growth: no synergism was observed in the mung bean agar. Because other studies find that soil amendment with ZnO NPs required high doses for inhibition of plant growth, the findings of pathogen growth control reported in this paper open the possibility of using ZnO NP-based formulations to complement existing strategies for improving crop health in field settings.


Asunto(s)
Antifúngicos/farmacología , Fusarium/efectos de los fármacos , Nanopartículas/toxicidad , Control Biológico de Vectores , Pseudomonas/fisiología , Óxido de Zinc/farmacología , Zinc/farmacología , Agar , Antibiosis , Cationes Bivalentes , Medios de Cultivo/química , Grano Comestible/microbiología , Fabaceae/química , Fusarium/crecimiento & desarrollo , Tamaño de la Partícula
17.
Prenat Diagn ; 33(10): 935-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23716482

RESUMEN

OBJECTIVE: Fetal reduction (FR) in multiples dramatically improves outcomes. We prioritize FR decisions for health and historically declined to factor gender. As male preferences apparently diminished, our bioethicist encouraged a re-evaluation. METHODS: Three hundred ninety-six patients reducing triplets or twins were categorized as 3➔2, 3➔1, and 2➔1, Major (M) anomaly or minor (m) anomaly, same gender (SG), and those for whom gender preference (GP) was possible. Higher order and non chorionic villus sampling were excluded. FR decisions were prioritized by M anomaly, Suspicious, or m anomaly. If neither, we considered GP. RESULTS: Of 319, 214 (67%) had either M/m or SG. Of those, 3➔2 with gender option: 71/79 chose male and female or had no preferences, one chose male/male, and seven chose female/female. We reduced monochorionic twins in 33/35 3➔1 cases. Of 20 with GP choice, 10 chose male and 10 chose female. Of 162 2➔1, 54 had M or m, 50 were SG, but of the 44 M/F twins, 20 chose male and 24 chose female. CONCLUSIONS: There has been a cultural shift mostly preferring one of each or having no preference. When reducing to one, >50% prefer a girl. In addition to identifying abnormalities, chorionic villus sampling before FR expands patient autonomy.


Asunto(s)
Conducta de Elección , Prioridad del Paciente , Reducción de Embarazo Multifetal/métodos , Embarazo Múltiple , Preselección del Sexo/métodos , Composición Familiar , Femenino , Humanos , Masculino , Prioridad del Paciente/estadística & datos numéricos , Embarazo , Reducción de Embarazo Multifetal/estadística & datos numéricos , Reducción de Embarazo Multifetal/tendencias , Embarazo Múltiple/estadística & datos numéricos , Estudios Retrospectivos , Factores Sexuales , Preselección del Sexo/psicología , Preselección del Sexo/estadística & datos numéricos , Trillizos , Gemelos
18.
Fetal Diagn Ther ; 33(4): 230-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23548741

RESUMEN

INTRODUCTION: To determine if nuchal translucency (NT) quality correlates with the extent to which clinics vary in rigor and quality control. METHODS: We correlated NT performance quality (bias and precision) of 246,000 patients with two alternative measures of clinic culture - % of cases for whom nasal bone (NB) measurements were performed and % of requisitions correctly filled for race-ethnicity and weight. RESULTS: When requisition errors occurred in <5% of cases, the average MoM (multiple of the median) was 0.97. When >5% (33%), the curve lowered to 0.93 MoM (p < 0.001) with both bias and precision of measurements impaired. Likewise, for centers with NB >90%, MoM was 0.99 compared to those <10% at 0.93 (p < 0.001). Precision and bias were highly correlated (p < 0.001). CONCLUSIONS: Rigor in NT measurements has improved, but the discussion has been confined to individuals. Progressive educational and remediation strategies need to expand to a second dimension - clinics themselves. Cross-clinic variation in NT quality exists independent of individual variation in NT quality, and two divergent indices of program rigor are associated with NT quality. Quality control must be program wide, and to effect continued improvement in the quality of NT results across time, the cultures of clinics must become a target for intervention.


Asunto(s)
Medida de Translucencia Nucal , Mejoramiento de la Calidad , Femenino , Humanos , Sistemas de Entrada de Órdenes Médicas , Medida de Translucencia Nucal/estadística & datos numéricos , Variaciones Dependientes del Observador , Cultura Organizacional , Embarazo , Atención Prenatal , Control de Calidad , Indicadores de Calidad de la Atención de Salud , Reproducibilidad de los Resultados , Estudios Retrospectivos
19.
Fetal Diagn Ther ; 34(3): 135-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24008494

RESUMEN

BACKGROUND: Gestational carriers and egg donors have been used by 'traditional' and now increasingly, gay couples. Three gay male couples, all using egg donors and gestational carriers with semen from both partners, had triplets. All desired reductions to twins for the standard medical indications, but requested, if reasonably possible, to have twins with one fathered by each partner. METHODS: Following our usual clinical protocol, we performed chorionic villus sampling at 12 weeks on all fetuses obtaining FISH and karyotype. For paternity analysis, 14 polymorphic molecular markers on villi were compared to DNA samples from the two men to include or exclude each. RESULTS: Standard assessments were all normal. Paternity testing showed that one partner fathered two of the triplets, and the other one. In all cases, one of the 'twins' was reduced with good clinical outcomes ensuing. CONCLUSIONS: Paternity balancing increases options for satisfying family planning desires of gay male couples. We believe it comparable to gender preferences in reductions, i.e. it can be considered but only completely subservient to any clinical criteria. Paternity balancing raises similar ethical issues as reduction with gender preferences, but may increase patient autonomy and mainstream acceptance of stable, gay families.


Asunto(s)
Paternidad , Reducción de Embarazo Multifetal/ética , Adulto , Muestra de la Vellosidad Coriónica , Familia , Femenino , Homosexualidad Masculina , Humanos , Hibridación Fluorescente in Situ , Cariotipo , Masculino , Persona de Mediana Edad , Embarazo , Embarazo Triple
20.
Reprod Sci ; 30(3): 835-853, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35799023

RESUMEN

Advances in medical technology do not follow a smooth process and are highly variable. Implementation can occasionally be rapid, but often faces varying degrees of resistance resulting at the very least in delayed implementation. Using qualitative comparative analysis, we have evaluated numerous technological advances from the perspective of how they were introduced, implemented, and opposed. Resistance varies from benign - often happening because of inertia or lack of resources to more active forms, including outright opposition using both appropriate and inappropriate methods to resist/delay changes in care. Today, even public health has become politicized, having nothing to do with the underlying science, but having catastrophic results. Two other corroding influences are marketing pressure from the private sector and vested interests in favor of one outcome or another. This also applies to governmental agencies. There are a number of ways in which papers have been buried including putting the thumb on the scale where reviewers can sabotage new ideas. Unless we learn to harness new technologies earlier in their life course and understand how to maneuver around the pillars of obstruction to their implementation, we will not be able to provide medical care at the forefront of technological capabilities.

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