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1.
Animals (Basel) ; 12(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35804570

RESUMEN

The avian inner perivitelline layer (IPVL), containing the zona pellucida (ZP) family of proteins, surrounds the ovulated ovum. In mammalian species, ZP proteins serve as key component(s) in binding sperm and initiating the acrosome reaction. Sperm binding at the germinal disc (GD) region of the IPVL initiates fertilization in avian species, and the amount of sperm binding at the GD reflects female fertility. The current research determined whether reported differences in mRNA expression in two genetic lines of turkey hens (E, high fertility and F, low fertility) translated to the protein level. ZPB2 in the IPVL is greater in the GD region compared with the nongerminal disc (NGD) region, as indicated by both mRNA and protein expression. However, protein expressions of ZPB1 and ZPC in the IPVL of E- and F-line turkey hens was in contrast to previously reported mRNA expression. The results indicate that the mRNA expression of ZP proteins at their site of synthesis in E- and F-line hens often does not directly correlate with the IPVL abundance of these proteins. The greater protein concentration of ZPB2 in the GD region compared with the NGD regions suggests that this protein may be critical for sperm binding at the GD region.

2.
Radiographics ; 39(4): 1098-1107, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31125293

RESUMEN

Facial transplant (FT) is a viable option for patients with severe craniomaxillofacial deformities. Transplant imaging requires coordination between radiologists and surgeons and an understanding of the merits and limitations of imaging modalities. Digital subtraction angiography and CT angiography are critical to mapping vascular anatomy, while volume-rendered CT allows evaluation of osseous defects and landmarks used for surgical cutting guides. This article highlights the components of successful FT imaging at two institutions and in two index cases. A deliberate stepwise approach to performance and interpretation of preoperative FT imaging, which consists of the modalities and protocols described here, is essential to seamless integration of the multidisciplinary FT team. ©RSNA, 2019 See discussion on this article by Lincoln .


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía por Tomografía Computarizada/métodos , Cara/diagnóstico por imagen , Trasplante Facial , Cuidados Preoperatorios/métodos , Adulto , Quemaduras/diagnóstico por imagen , Quemaduras/cirugía , Anomalías Craneofaciales/diagnóstico por imagen , Anomalías Craneofaciales/cirugía , Huesos Faciales/diagnóstico por imagen , Traumatismos Faciales/diagnóstico por imagen , Traumatismos Faciales/cirugía , Humanos , Imagenología Tridimensional , Masculino , Selección de Paciente , Flebografía/métodos , Adulto Joven
3.
Prehosp Emerg Care ; 23(3): 319-326, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30257596

RESUMEN

OBJECTIVE: Ambulance patient offload time (APOT) also known colloquially as "Wall time" has been described in various jurisdictions but seems to be highly variable. Any attempt to improve APOT requires the use of common definitions and standard methodology to measure the extent of the problem. METHODS: An Ambulance Offload Delay Task Force in California developed a set of standard definitions and methodology to measure APOT for transported 9-1-1 patients. It is defined as the time "interval between the arrival of an ambulance at an emergency department and the time that the patient is transferred to an ED gurney, bed, chair or other acceptable location and the ED assumes responsibility for care of the patient." Local EMS agencies voluntarily reported data according to the standard methodology to the California EMS Authority (State agency). RESULTS: Data were reported for 9-1-1 transports during 2017 from 9 of 33 local EMS Agencies in California that comprise 37 percent of the state population. These represent 830,637 ambulance transports to 126 hospitals. APOT shows significant variation by EMS agency with half of the agencies demonstrating significant delays. Offload times vary markedly by hospital as well as by region. Three-fourths of hospitals detained EMS crews more than one hour, 40% more than two hours, and one-third delayed EMS return to service by more than three hours. CONCLUSION: This first step to address offload delays in California consists of standardized definitions for data collection to address the significant variability inherent in obtaining data from 33 local agencies, hundreds of EMS provider agencies, and 320 acute care hospital Emergency Departments that receive 9-1-1 ambulance transports. The first year of standardized data collection of ambulance patient offload times revealed significant ambulance patient offload time delays that are not distributed uniformly, resulting in a substantial financial burden for some EMS providers in California.


Asunto(s)
Ambulancias , Benchmarking , Eficiencia Organizacional , Servicios Médicos de Urgencia , Hospitalización , Transporte de Pacientes/normas , Ambulancias/estadística & datos numéricos , California , Servicios Médicos de Urgencia/estadística & datos numéricos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Humanos , Factores de Tiempo
4.
Magn Reson Imaging Clin N Am ; 26(1): 19-35, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29128004

RESUMEN

Perfusion and permeability computed tomography and MR imaging applied to head and neck cancer provide powerful diagnostic and prognostic tools for clinicians. Understanding the basics of these techniques allows the radiologist to make informed decisions regarding the use of modeling algorithms, acquisition parameters, and postprocessing techniques. This helps to ensure that studies are acquired, analyzed, and reported appropriately and erroneous results are avoided. These techniques are highly automated, widely available, and can be easily and safely incorporated into daily imaging workflow.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Cabeza/diagnóstico por imagen , Humanos , Cuello/diagnóstico por imagen
5.
J Agric Food Chem ; 64(11): 2209-13, 2016 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-26949980

RESUMEN

Benning(M) and Benning(MGH) are near-isogenic lines (NILs) of the soybean cultivar Benning, which contain insect-resistance quantitative trait loci (QTLs) from the soybean accession PI 229358. Benning(M) contains QTL-M, which confers antibiosis and antixenosis. In addition to QTL-M, Benning(MGH) contains QTL-G, which confers antibiosis, and QTL-H, which confers antixenosis. Soybean meal was produced from Benning and the NILs. Nutritional composition, digestible amino acid content, and nitrogen-corrected true metabolizable energy (TMEN) were equivalent among soybean meals. A 21-day broiler feeding trial was carried out to determine if the QTLs affect soybean meal quality. Weight gain and feed-to-gain ratio were evaluated. No biologically significant differences were detected for broilers fed Benning, Benning(M), and Benning(MGH). This demonstrates that soybean meal produced from the insect-resistant NILs is equivalent to soybean meal produced from their non-insect-resistant parent cultivar for broiler weight gain.


Asunto(s)
Alimentación Animal , Glycine max , Plantas Modificadas Genéticamente , Alimentación Animal/análisis , Animales , Pollos , Insectos , Valor Nutritivo , Control Biológico de Vectores , Plantas Modificadas Genéticamente/genética , Sitios de Carácter Cuantitativo , Glycine max/química
6.
J Comput Assist Tomogr ; 39(6): 876-81, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26359580

RESUMEN

OBJECTIVE: Sequential computed tomography (CT) technique remains the most common protocol for CT evaluation of the head despite nearly universal adoption of continuous technique for all other body parts. This may be attributable to the belief by radiologists that this technique is superior to helical scanning uniquely for this indication. This study attempts to clarify the issue. METHODS: A phantom evaluation and a prospective randomized clinical image quality trial were performed comparing sequential and helical technique using the most current generation 128-row detector CT scanner. RESULTS: Phantom evaluation demonstrated equivalence between the 2 techniques for low-contrast resolution and line pair spatial discrimination. Continuous scanning provided the highest contrast-to-noise ratio. There was no significant difference between the 2 techniques regarding image quality except for cortical visualization at the cerebral hemispheres, which was subtly but significantly superior for sequential technique. CONCLUSIONS: Head CT image quality for sequential and continuous techniques are virtually equivalent.


Asunto(s)
Cabeza/diagnóstico por imagen , Fantasmas de Imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Humanos , Estudios Prospectivos , Tomógrafos Computarizados por Rayos X , Tomografía Computarizada Espiral
7.
Otol Neurotol ; 36(9): 1486-91, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26375970

RESUMEN

OBJECTIVE: To validate a method of measuring angular depth of insertion (aDOI) as well as positional depth of each electrode contact in a cochlear implant by using intraoperative postinsertion skull radiographs. STUDY DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: Intraoperative postinsertion radiographs obtained from 18 cochlear implant recipients were chosen for analysis. One high-resolution computer tomography scan of the head with the electrode in place was also analyzed. One cadaveric temporal bone with an inserted electrode provided additional data for analysis. INTERVENTION: aDOI and position of each electrode contact were measured from the radiographs using readily available software. High-resolution computer tomography imaging of the cochlea and electrode were reconstructed in three dimensions and used to simulate head rotation during intraoperative radiographs. The cadaveric temporal bone was imaged by x-ray at various acquisition angles. MAIN OUTCOME MEASURES: We evaluated the error introduced in measuring aDOI by assessing intra- and inter-rater variability. We also evaluated the error introduced by x-ray acquisition at nonstandardized angles by analyzing the three-dimensional construct and the cadaveric temporal bone. RESULTS: The concordance correlation coefficients for intrarater (0.991) and inter-rater (0.996) variability in aDOI measurement were excellent. The error introduced by nonstandardized x-ray acquisition angles was only -12.5 degrees to +15.8 degrees even at the limits of clinically relevant head rotation. CONCLUSIONS: The intraoperative postinsertion radiograph is sufficient for estimating positional depth of electrode contacts and the aDOI. This measure is robust in the face of nonstandardized x-ray acquisition angles, and shows good intra- and inter-rater variability.


Asunto(s)
Cóclea/diagnóstico por imagen , Implantación Coclear/métodos , Implantes Cocleares , Hueso Temporal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Niño , Cóclea/cirugía , Electrodos Implantados , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Cuidados Intraoperatorios/métodos , Masculino , Estudios Retrospectivos , Programas Informáticos , Cirugía Asistida por Computador , Hueso Temporal/cirugía
9.
Proc Natl Acad Sci U S A ; 107(46): 19685-90, 2010 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-21041679

RESUMEN

Ground level ozone concentrations ([O(3)]) typically show a direct linear relationship with surface air temperature. Three decades of California measurements provide evidence of a statistically significant change in the ozone-temperature slope (Δm(O3-T)) under extremely high temperatures (> 312 K). This Δm(O3-T) leads to a plateau or decrease in [O(3)], reflecting the diminished role of nitrogen oxide sequestration by peroxyacetyl nitrates and reduced biogenic isoprene emissions at high temperatures. Despite inclusion of these processes in global and regional chemistry-climate models, a statistically significant change in Δm(O3-T) has not been noted in prior studies. Future climate projections suggest a more frequent and spatially widespread occurrence of this Δm(O3-T) response, confounding predictions of extreme ozone events based on the historically observed linear relationship.


Asunto(s)
Fenómenos Biofísicos , Fenómenos Químicos , Retroalimentación , Calor , Ozono/análisis , Butadienos/análisis , California , Simulación por Computador , Geografía , Hemiterpenos/análisis , Modelos Estadísticos , Pentanos/análisis
10.
Retrovirology ; 5: 115, 2008 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-19091128

RESUMEN

BACKGROUND: HIV-1 reverse transcriptase (RT) is a heterodimer composed of p66 and p51 subunits and is responsible for reverse transcription of the viral RNA genome into DNA. RT can be post-translationally modified in vitro which may be an important mechanism for regulating RT activity. Here we report detection of different p66 and p51 RT isoforms by 2D gel electrophoresis in virions and infected cells. RESULTS: Major isoforms of the p66 and p51 RT subunits were observed, with pI's of 8.44 and 8.31 respectively (p66(8.44) and p51(8.31)). The same major isoforms were present in virions, virus-infected cell lysates and intracellular reverse transcription complexes (RTCs), and their presence in RTCs suggested that these are likely to be the forms that function in reverse transcription. Several minor RT isoforms were also observed. The observed pIs of the RT isoforms differed from the pI of theoretical unmodified RT (p66(8.53) and p51(8.60)), suggesting that most of the RT protein in virions and cells is post-translationally modified. The modifications of p66(8.44) and p51(8.31) differed from each other indicating selective modification of the different RT subunits. The susceptibility of RT isoforms to phosphatase treatment suggested that some of these modifications were due to phosphorylation. Dephosphorylation, however, had no effect on in vitro RT activity associated with virions, infected cells or RTCs suggesting that the phospho-isoforms do not make a major contribution to RT activity in an in vitro assay. CONCLUSION: The same major isoform of p66 and p51 RT is found in virions, infected cells and RTC's and both of these subunits are post-translationally modified. This post-translational modification of RT may be important for the function of RT inside the cell.


Asunto(s)
VIH-1/química , ADN Polimerasa Dirigida por ARN/química , ADN Polimerasa Dirigida por ARN/metabolismo , Virión/química , Extractos Celulares/química , Línea Celular , Electroforesis en Gel Bidimensional , Humanos , Punto Isoeléctrico , Fosforilación , Isoformas de Proteínas/análisis , Procesamiento Proteico-Postraduccional , Proteoma/análisis
11.
Health Phys ; 94(2): 145-60, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18188049

RESUMEN

Beginning around 1940, private companies began processing of uranium and thorium ore, compounds, and metals for the Manhattan Engineer District and later the U.S. Atomic Energy Commission (AEC). Personnel from the AEC's Health and Safety Laboratory (HASL) visited many of the plants to assess worker exposures to radiation and radioactive materials. They developed a time-and-task approach to estimating "daily weighted average" (DWA) concentrations of airborne uranium, thorium, radon, and radon decay products. While short-term exposures greater than 10(5) dpm m(-3) of uranium and greater than 10(5) pCi L(-1) of radon were observed, DWA concentrations were much lower. The HASL-reported DWA values may be used as inputs for dose reconstruction in support of compensation decisions, but they have no numerical uncertainties associated with them. In this work, Monte Carlo methods are used retrospectively to assess the uncertainty and variability in the DWA values for 63 job titles from five different facilities that processed U, U ore, Th, or 226Ra-222Rn between 1948 and 1955. Most groups of repeated air samples are well described by lognormal distributions. Combining samples associated with different tasks often results in a reduction of the geometric standard deviation (GSD) of the DWA to less than those GSD values typical of individual tasks. Results support the assumption of a GSD value of 5 when information on uncertainty in DWA exposures is unavailable. Blunders involving arithmetic, transposition, and transcription are found in many of the HASL reports. In 5 out of the 63 cases, these mistakes result in overestimates of DWA values by a factor of 2 to 2.5, and in 2 cases DWA values are underestimated by factors of 3 to 10.


Asunto(s)
Contaminantes Radiactivos del Aire , Monitoreo de Radiación/métodos , Incertidumbre , Exposición a Riesgos Ambientales , Humanos , National Institute for Occupational Safety and Health, U.S. , Energía Nuclear , Dosis de Radiación , Reproducibilidad de los Resultados , Estados Unidos
12.
Virology ; 372(1): 147-56, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18037155

RESUMEN

Virion infectivity factor (Vif) facilitates HIV infection by counteracting APOBEC3G late in replication in virus-producer cells. Here, we show that early after infection of new target cells Vif is part of the HIV reverse transcription machinery and acts as an accessory factor for reverse transcription. Vif protein was present in gradient fractions containing reverse transcription complexes (RTCs), and anti-Vif antibody immunoprecipitated HIV reverse transcription products from these gradient fractions. To investigate a role for Vif in RTCs independent of APOBEC3G, we created an intracellular environment that would restrict reverse transcription by pre-treating permissive target cells with 5-Fluoro 2-deoxyuridine, a thymidylate synthetase inhibitor, prior to infection with virus from permissive cells. Infectivity assays and quantitation of reverse transcription products demonstrated that replication of HIV lacking Vif was inhibited to a greater degree than wild type, without concurrent mutation of reverse transcription products, suggesting compromised reverse transcription in the absence of Vif.


Asunto(s)
VIH-1/fisiología , VIH-1/patogenicidad , Transcripción Reversa , Replicación Viral , Productos del Gen vif del Virus de la Inmunodeficiencia Humana/metabolismo , Línea Celular , Centrifugación por Gradiente de Densidad , Floxuridina/farmacología , VIH-1/genética , Células HeLa , Humanos , Inmunoprecipitación , Timidilato Sintasa/antagonistas & inhibidores
13.
J Nutr Biochem ; 16(2): 114-20, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15681171

RESUMEN

Chicken hepatic histidase activity varies with dietary protein consumption, but the mechanisms responsible for this alteration in activity are unclear. In the present research, the complete coding sequence and deduced amino acid sequence for chicken histidase was determined from clones isolated from a chicken liver cDNA library. The deduced amino acid sequence of chicken histidase has greater than 85% identity with the amino acid sequences of rat, mouse, and human histidase. In a series of four experiments, broiler chicks were allowed free access for 1.5, 3, 6, or 24 h to a low (13 g/100 g diet), basal (22 g/100 g diet) and high (40 g/100 g diet) protein diet. In the final experiment 5, chicks were allowed free access for 24 h to the basal, high protein diet or the basal diet supplemented with three different levels of l-histidine (0.22 g/100 g diet, 0.43 g/100 g diet or 0.86 g/100 g diet). There were no differences in the expression of the mRNA for histidase at 1.5 h, but at 3 h, histidase mRNA expression was significantly (P < .05) greater in chicks fed the high protein diet compared to chicks fed the low protein diet. At 6 and 24 h, histidase mRNA expression was significantly enhanced in chicks fed the high protein diet, and significantly reduced in chicks fed the low protein diet, compared with chicks fed the basal diet. Histidase mRNA expression was not altered by supplementing the basal diet with histidine. The results suggest that previously observed alterations in the activity of histidase, which were correlated to dietary protein intake, are mediated by rapid changes in the mRNA expression of this enzyme, and are not necessarily related to dietary histidine intake.


Asunto(s)
Pollos/genética , Clonación Molecular , Proteínas en la Dieta/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Histidina Amoníaco-Liasa/genética , Hígado/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Histidina/administración & dosificación , Histidina Amoníaco-Liasa/química , Humanos , Ratones , Datos de Secuencia Molecular , ARN Mensajero/análisis , Ratas , Homología de Secuencia
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