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1.
Mol Ecol ; 23(22): 5480-95, 2014 11.
Artículo en Inglés | MEDLINE | ID: mdl-25294029

RESUMEN

Patterns of population structure and historical genetic demography of blacknose sharks in the western North Atlantic Ocean were assessed using variation in nuclear-encoded microsatellites and sequences of mitochondrial (mt)DNA. Significant heterogeneity and/or inferred barriers to gene flow, based on microsatellites and/or mtDNA, revealed the occurrence of five genetic populations localized to five geographic regions: the southeastern U.S Atlantic coast, the eastern Gulf of Mexico, the western Gulf of Mexico, Bay of Campeche in the southern Gulf of Mexico and the Bahamas. Pairwise estimates of genetic divergence between sharks in the Bahamas and those in all other localities were more than an order of magnitude higher than between pairwise comparisons involving the other localities. Demographic modelling indicated that sharks in all five regions diverged after the last glacial maximum and, except for the Bahamas, experienced post-glacial, population expansion. The patterns of genetic variation also suggest that the southern Gulf of Mexico may have served as a glacial refuge and source for the expansion. Results of the study demonstrate that barriers to gene flow and historical genetic demography contributed to contemporary patterns of population structure in a coastal migratory species living in an otherwise continuous marine habitat. The results also indicate that for many marine species, failure to properly characterize barriers in terms of levels of contemporary gene flow could in part be due to inferences based solely on equilibrium assumptions. This could lead to erroneous conclusions regarding levels of connectivity in species of conservation concern.


Asunto(s)
Flujo Génico , Genética de Población , Tiburones/genética , Migración Animal , Animales , Océano Atlántico , Teorema de Bayes , Conservación de los Recursos Naturales , ADN Mitocondrial/genética , Femenino , Variación Genética , Genotipo , Geografía , Haplotipos , Masculino , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
2.
Environ Int ; 178: 108065, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37562341

RESUMEN

The mobilisation of potentially harmful chemical constituents in wildfire ash can be a major consequence of wildfires, posing widespread societal risks. Knowledge of wildfire ash chemical composition is crucial to anticipate and mitigate these risks. Here we present a comprehensive dataset on the chemical characteristics of a wide range of wildfire ashes (42 types and a total of 148 samples) from wildfires across the globe and examine their potential societal and environmental implications. An extensive review of studies analysing chemical composition in ash was also performed to complement and compare our ash dataset. Most ashes in our dataset had an alkaline reaction (mean pH 8.8, ranging between 6 and 11.2). Important constituents of wildfire ash were organic carbon (mean: 204 g kg-1), calcium, aluminium, and iron (mean: 47.9, 17.9 and 17.1 g kg-1). Mean nitrogen and phosphorus ranged between 1 and 25 g kg-1, and between 0.2 and 9.9 g kg-1, respectively. The largest concentrations of metals of concern for human and ecosystem health were observed for manganese (mean: 1488 mg kg-1; three ecosystems > 1000 mg kg-1), zinc (mean: 181 mg kg-1; two ecosystems > 500 mg kg-1) and lead (mean: 66.9 mg kg-1; two ecosystems > 200 mg kg-1). Burn severity and sampling timing were key factors influencing ash chemical characteristics like pH, carbon and nitrogen concentrations. The highest readily dissolvable fractions (as a % of ash dry weight) in water were observed for sodium (18 %) and magnesium (11.4 %). Although concentrations of elements of concern were very close to, or exceeded international contamination standards in some ashes, the actual effect of ash will depend on factors like ash loads and the dilution into environmental matrices such as water, soil and sediment. Our approach can serve as an initial methodological standardisation of wildfire ash sampling and chemical analysis protocols.


Asunto(s)
Incendios Forestales , Humanos , Ecosistema , Agua/análisis , Magnesio/análisis , Carbono/análisis , Nitrógeno , Factores Socioeconómicos
3.
Avian Pathol ; 40(2): 207-11, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21500041

RESUMEN

Disseminated histoplasmosis caused by Histoplasma capsulatum, a zoonotic fungal organism, is an important disease in animals and humans, particularly those with compromised immune systems. Reports of disseminated histoplasmosis in an avian species are not available within the current literature. Candida albicans, another fungal agent with zoonotic importance, is a commensal of the avian digestive tract that is often associated with opportunistic infections particularly in young or immunocompromised birds. This report describes a case of concomitant histoplasmosis and candidiasis in an Eclectus parrot (Eclectus roratus) characterized by severe granulomatous glossitis, blepharitis and osteomyelitis with numerous intrahistiocytic and extracellular yeasts (H. capsulatum) as well as intralesional hyphae, pseudohyphae and conidia (C. albicans). To our knowledge, co-infection with H. capsulatum and C. albicans has not been reported in an avian species.


Asunto(s)
Enfermedades de las Aves/microbiología , Candidiasis Bucal/veterinaria , Histoplasmosis/veterinaria , Loros/microbiología , Animales , Enfermedades de las Aves/patología , Blefaritis/microbiología , Blefaritis/patología , Blefaritis/veterinaria , Candida albicans/patogenicidad , Candidiasis Bucal/complicaciones , Candidiasis Bucal/microbiología , Candidiasis Bucal/patología , Eutanasia Animal , Párpados/microbiología , Párpados/patología , Resultado Fatal , Femenino , Glositis/microbiología , Glositis/patología , Glositis/veterinaria , Histoplasma/patogenicidad , Histoplasmosis/complicaciones , Histoplasmosis/microbiología , Histoplasmosis/patología , Humanos , Huésped Inmunocomprometido , Osteomielitis/microbiología , Osteomielitis/patología , Osteomielitis/veterinaria , Lengua/microbiología , Lengua/patología , Zoonosis/microbiología
4.
Mult Scler Relat Disord ; 49: 102743, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33486399

RESUMEN

BACKGROUND: Reliably monitoring changes in fatigue is an ongoing concern. OBJECTIVE: Evaluate reliable change using the Modified Fatigue Impact Scale 5-item version (MFIS-5) in people with MS (PwMS). METHODS: The MFIS-5 was administered at three time points in 157 PwMS. Test-retest reliability and reliable change scores were calculated at the 0.70, 0.80, 0.90, and 0.95 confidence intervals. RESULTS: Difference scores of 3, 4, 5, and 6 represent statistically meaningful change at the 0.70, 0.80, 0.90, and 0.95 confidence intervals, respectively. CONCLUSION: Cut points derived from this study and prior work can help reliably assess changes in fatigue over time.


Asunto(s)
Esclerosis Múltiple , Fatiga/diagnóstico , Humanos , Reproducibilidad de los Resultados
5.
J Heart Lung Transplant ; 13(2): 282-91, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8031813

RESUMEN

Between August 1982 and December 1992, 260 patients were accepted for heart and lung transplantation, of whom 139 patients underwent transplant surgery. One hundred twenty-one patients have not received transplants, of whom 80 have died, four were transferred to other lists, and 37 were still waiting for suitable organs at the close of the study. Median waiting time for those patients who underwent heart and lung transplantation was 7 months, whereas patients who died waiting spent a median of 5 months on the list. Recipients are matched to donor organs according to blood type, size (total lung capacity), and cytomegalovirus antibody status. These factors, along with age, gender, underlying diagnosis, and Toxoplasma antibody status, were studied to assess their influence on survival after acceptance and time to transplantation. The only characteristic that significantly influenced survival after acceptance was the underlying disease, with patients with Eisenmenger's syndrome having significantly longer survival than the other groups (relative risk = 0.21; p < 0.001). Patients with Eisenmenger's syndrome underwent transplantation at a slower rate than did other patients (relative risk = 0.51; p = 0.012). Patients who had a total lung capacity of more than 6 L underwent transplantation significantly more quickly than did smaller patients (relative risk = 1.98; p = 0.005). Male patients underwent heart and lung transplantation at a quicker rate than did female patients (relative risk = 1.86; p < 0.001), although this was related to size. Patients who had cytomegalovirus-positive antibodies underwent transplantation at almost twice the rate of patients who had cytomegalovirus-negative antibodies (relative risk = 1.92; p < 0.001). Age at acceptance, blood type, and Toxoplasma status did not significantly influence time to heart and lung transplantation. In summary, cytomegalovirus antibody status, patient size, and gender significantly affect the waiting time to heart and lung transplantation. Patients with Eisenmenger's syndrome wait longer than other patients as a result of the natural history of their disease.


Asunto(s)
Insuficiencia Cardíaca/cirugía , Trasplante de Corazón-Pulmón/mortalidad , Trasplante de Pulmón/mortalidad , Insuficiencia Respiratoria/cirugía , Obtención de Tejidos y Órganos/estadística & datos numéricos , Listas de Espera , Adolescente , Adulto , Anticuerpos Antivirales/análisis , Niño , Preescolar , Citomegalovirus/inmunología , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/mortalidad , Prueba de Histocompatibilidad , Humanos , Lactante , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Insuficiencia Respiratoria/mortalidad , Factores de Riesgo , Análisis de Supervivencia
6.
Arch Ophthalmol ; 104(2): 196-200, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3947292

RESUMEN

A series of 54 eyes in 50 patients had preoperative predictions of postoperative visual acuity, using both a white-light interferometer (Lotmar Visometer) and a Snellen chart projector (Guyton-Minkowski Potential Acuity Meter). The predicted vision by each instrument was compared with the actual postoperative vision. Forty eyes in 36 of these patients, 25 with concurrent eye disease, had cataract extraction with intraocular lens implantation. Fifteen eyes in 15 patients, 11 with concurrent eye disease, had neodymium-YAG laser posterior capsulotomy. The Visometer gave more accurate predictions than the Potential Acuity Meter in cataract patients with open angle glaucoma, even with glaucomatous visual field loss, and in patients with a visual acuity of less than 20/400 due to advanced cataract formation.


Asunto(s)
Oftalmología/instrumentación , Agudeza Visual , Adulto , Anciano , Extracción de Catarata , Estudios de Evaluación como Asunto , Humanos , Interferometría/instrumentación , Lentes Intraoculares , Persona de Mediana Edad , Periodo Posoperatorio , Pronóstico
7.
J Virol Methods ; 74(1): 21-9, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9763125

RESUMEN

The development of a nested polymerase chain reaction (PCR) assay is described to detect low concentrations of monodon baculovirus (MBV) DNA from total Penaeus monodon postlarval DNA. A modified DNA extraction procedure was also developed to circumvent problems associated with co-purification of PCR inhibitors in total DNA extracted from whole postlarvae. This method involved mechanical disruption of frozen prawn material immediately followed by phenol extraction at high temperature. An assessment of the sensitivity of the assay demonstrated detection down to eight viral genome equivalents. The PCR was shown to be specific for MBV DNA by not amplifying prawn DNA or DNA preparations of Baculovirus penaei (BP), white spot baculovirus (WSBV), bennettae baculovirus and insect Autographica californica nuclear polyhedrosis virus (NPV). A colourimetric method of PCR product detection was used to simplify final analysis.


Asunto(s)
Baculoviridae/aislamiento & purificación , Penaeidae/virología , Reacción en Cadena de la Polimerasa/métodos , Animales , Baculoviridae/genética , Secuencia de Bases , Colorimetría , Cartilla de ADN , ADN Viral/análisis , Larva , Datos de Secuencia Molecular , Sensibilidad y Especificidad
8.
Talanta ; 22(9): 751-3, 1975 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18961723

RESUMEN

A simple and rapid semi-micro gravimetric procedure for the determination of carbon dioxide (0.005-60%) in coal, rocks and minerals is described. Particular advantages include small sample weights (0.25-1.0 g), high precision (relative standard deviation 0.01%) and improved speed of analyses (20 min). The apparatus is designed as a simple vertical layout to minimize bench space requirements and utilizes commercially available components to reduce the number of joints and rubber tubing connections. The low swept volume (165ml) gives good sensitivity and reduced analysis time, and the scavenging train ensures removal of water, halogens and gaseous sulphur compounds.

9.
Talanta ; 22(10-11): 777-9, 1975.
Artículo en Inglés | MEDLINE | ID: mdl-18961733

RESUMEN

A method is described for the spectrophotometric determination of 0-4% silicon in ferrophosphorus, following fusion with sodium peroxide in a zirconium crucible. Silicomolybdic acid is formed with sodium molybdate. The acidity is increased to 2N and the solution stood for 10 min to destroy phosphomolybdic and arsenomolybdic acids. The silicomolybdic acid is reduced with ascorbic acid and the absorbance measured at 810 nm. The colour is stable, and a standard deviation of 0.006% was achieved for 0.7% silicon. Results obtained for three samples with alternative procedures are compared.

10.
Talanta ; 25(7): 398-400, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18962283

RESUMEN

The selective-electrode procedure described for determining 0.2-2.5% of nitrogen in coal and coke offers significant advantages over Kjeldahl distillation and titration. The Kjeldahl digest is diluted, neutralized, cooled, diluted to volume, adjusted to a standard temperature and rendered alkaline prior to measurement with an ammonia-selective electrode. Accuracy and precision of 1% relative are demonstrated by comparative analyses of a range of samples. Important experimental aspects discussed include the role as neutralization indicator played by vanadium derived from the catalyst, precision of the mV-meter, the influence of solution temperature and concentration, the repeatability of the readings, and interferences.

11.
Talanta ; 23(11-12): 815-8, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-18961988

RESUMEN

Five sample presentation techniques were examined for the X-ray fluorescence spectrometric analysis of tungsten carbide alloys in powder and cemented forms. Powder samples may be oxidized by air at 600 degrees before fusion (I), or preferably by lithium nitrate during fusion (II); the fusion is effected with lithium-lanthanum tetraborate followed by briquetting with graphite. Powder samples may also be blended with wax and briquetted (III). Cemented carbides are surface-prepared with silicon carbide before analysis (V). Briquettes prepared by blending carbide powder, lithium-lanthanum tetraborate and graphite (IV), give poor reproducibility, however, owing to micro-absorption effects the technique is not recommended. The determination of eight common elements in tungsten carbide is discussed and the relative standard deviations are 0.002-0.004 for major and 0.008-0.01 for minor elements.

12.
Equine Vet J Suppl ; (41): 69-75, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22594030

RESUMEN

REASON FOR PERFORMING STUDY: The repeatability of various echocardiographic measurements is unknown. OBJECTIVES: To determine the intraoperator, intraobserver and interoperator variability of echocardiographic measures in healthy foals. METHODS: Echocardiographic examinations were carried out on 6 healthy foals by 3 experienced echocardiographers. Intraoperator variability was determined by having a single echocardiographer obtain and measure images from 6 foals scanned on 3 consecutive days. Interoperator and intraobserver variability were determined by having 3 echocardiographers each obtain images from an additional 6 sedated foals. Within-day interoperator variability was determined by having each echocardiographer measure their own images. Intraobserver variability was determined by having a single echocardiographer measure images obtained by all 3 echocardiographers. The coefficient of variation (CV) and standard error were calculated for each measure. RESULTS: The variability for most measurements was either very low (CV < 5%) or low (CV = 5-15%). Measurements of right ventricular internal diameter (RVID) in systole and E-point to septal separation (EPSS) showed moderate (CV 15-25%) to high variability (CV > 25%) in all 3 categories. Measurements of the left ventricular ejection time (LVET) and velocity time integral from the right parasternal long axis view of right outflow tract in the fourth intercostal space showed moderate intraoperator variability. Measurements of the LVET, RVID in diastole and left atrial appendage (LAA) showed moderate interoperator variability and measurements of the RVID in diastole and acceleration time from the short axis view of the right outflow tract in the right third intercostal space showed moderate interobserver variability. CONCLUSION: The intraoperator, intraobserver and interoperatorvariabilities for most echocardiographic measurements in foals are low. POTENTIAL RELEVANCE: Most standard transthoracic echocardiographic measurements in foals have a low enough variability to warrant their use in serial clinical evaluations or experimental studies. Repeated measurements of RVID, EPSS, LVET and LAA should be interpreted with caution.


Asunto(s)
Ecocardiografía/veterinaria , Corazón/anatomía & histología , Caballos/anatomía & histología , Animales , Femenino , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
13.
Rev Sci Instrum ; 83(10): 10D505, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23130789

RESUMEN

An in-vessel calibration light source (ICLS) has been implemented for remote use during extended shutdown periods of the Joint European Torus (JET). The ICLS facilitated the in situ calibration of optical diagnostics, which previously were performed when the diagnostics were removed from JET. Since the ICLS is used to calibrate diagnostics over the entire, exact optical path as used when plasma discharge data are measured, the ICLS calibration implicitly accounts for any vignetting losses in the JET vessel viewports in addition to the vacuum window transmission. At least ten diagnostic systems have benefited from the ICLS during the extended ITER-like wall shutdown of 2009-2011. Examples of the use of the ICLS in JET are given.


Asunto(s)
Luz , Fenómenos Magnéticos , Física/instrumentación , Calibración , Gases em Plasma/química
15.
Curr Mol Med ; 10(1): 82-94, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20205681

RESUMEN

Cystic Fibrosis (CF) is an autosomal recessive disorder caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) that regulates epithelial surface fluid secretion in respiratory and gastrointestinal tracts. The deletion of phenylalanine at position 508 (DeltaF508) in CFTR is the most common mutation that results in a temperature sensitive folding defect, retention of the protein in the endoplasmic reticulum (ER), and subsequent degradation by the proteasome. ER associated degradation (ERAD) is a major quality control pathway of the cell. The majority (99%) of the protein folding, DeltaF508-, mutant of CFTR is known to be degraded by this pathway to cause CF. Recent studies have revealed that inhibition of DeltaF508-CFTR ubiquitination and proteasomal degradation can increase its cell surface expression and may provide an approach to treat CF. The finely tuned balance of ER membrane interactions determine the cytosolic fate of newly synthesized CFTR. These ER membrane interactions induce ubiquitination and proteasomal targeting of DeltaF508- over wild type- CFTR. We discuss here challenges and therapeutic strategies targeting protein processing of DeltaF508-CFTR with the goal of rescuing functional DeltaF508-CFTR to the cell surface. It is evident from recent studies that CFTR plays a critical role in inflammatory response in addition to its well-described ion transport function. Previous studies in CF have focused only on improving chloride efflux as a marker for promising treatment. We propose that methods quantifying the therapeutic efficacy and recovery from CF should not include only changes in chloride efflux, but also recovery of the chronic inflammatory signaling, as evidenced by positive changes in inflammatory markers (in vitro and ex vivo), lung function (pulmonary function tests, PFT), and chronic lung disease (state of the art molecular imaging, in vivo). This will provide novel therapeutics with greater opportunities of potentially attenuating the progression of the chronic CF lung disease.


Asunto(s)
Fibrosis Quística/genética , Fibrosis Quística/metabolismo , Inflamación/etiología , Procesamiento Proteico-Postraduccional , Transducción de Señal , Animales , Fibrosis Quística/inmunología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Humanos , Inflamación/patología
16.
Arch Ophthalmol ; 101(2): 304, 1983 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6824479
17.
20.
J Glaucoma ; 2(2): 114-8, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-19920498
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