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1.
Br J Anaesth ; 120(5): 904-913, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29661408

RESUMEN

BACKGROUND: Cerebrospinal-fluid (CSF) drainage is recommended by current guidelines for spinal protection during open and endovascular repairs of thoracic and thoraco-abdominal aortic aneurysms. In the published literature, great variability exists in the rate of CSF-related complications and morbidity. Herein, we perform a systematic review and meta-analysis on the incidence of CSF drainage-related complications, and compare the complication rates between open and endovascular repairs. METHODS: The systematic review was conducted according to the Meta-Analysis of Observational Studies in Epidemiology guidelines. Thirty-four studies (4714 patients) were included in the quantitative analysis. The CSF drainage-related complications were categorised as mild, moderate, and severe. Pooled event rates for each complication category were estimated using a random-effect model. Random-effect uni- and multivariable meta-regression analyses were used to assess the effect of aortic-repair approach (open vs endovascular) and the CSF drainage criteria on CSF drainage-related complications. RESULTS: The pooled event rates were 6.5% [95% confidence interval (CI): 4.3-9.8%] for overall complications, 2% (95% CI: 1.1-3.4%) for minor complications, 3.7% (95% CI: 2.5-5.6%) for moderate complications, and 2.5% (95% CI: 1.6-3.8%) for severe complications. The drainage-related-mortality pooled event rate was 0.9% (95% CI: 0.6-1.4%). The uni- and multivariable meta-regression analyses showed no difference in complication rates between the open and endovascular approaches, or between the different CSF drainage protocols. CONCLUSION: The complication rate for CSF drainage is not negligible. Our results help define a more accurate risk-benefit ratio for CSF drain placement at the time of repair of thoracic and thoraco-abdominal aneurysms.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Drenaje/métodos , Procedimientos Endovasculares/métodos , Complicaciones Posoperatorias/líquido cefalorraquídeo , Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/líquido cefalorraquídeo , Humanos , Resultado del Tratamiento
3.
J Helminthol ; 92(3): 379-386, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28637526

RESUMEN

The extent of New Zealand's freshwater fish-parasite diversity has yet to be fully revealed, with host-parasite relationships still to be described from nearly half the known fish community. While advances in the number of fish species examined and parasite taxa described are being made, some parasite groups, such as nematodes, remain poorly understood. In the present study we combined morphological and molecular analyses to characterize a capillariid nematode found infecting the swim bladder of the brown mudfish Neochanna apoda, an endemic New Zealand fish from peat-swamp-forests. Morphologically, the studied nematodes are distinct from other Capillariinae taxa by the features of the male posterior end, namely the shape of the bursa lobes, and shape of spicule distal end. Male specimens were classified into three different types according to differences in the shape of the bursa lobes at the posterior end, but only one was successfully characterized molecularly. Molecular analysis indicated that the studied capillariid is distinct from other genera. However, inferences about the phylogenetic position of the capillariid reported here will remain uncertain, due to the limited number of Capillariinae taxa characterized molecularly. The discovery of this new capillariid, which atypically infects the swim bladder of its host, which itself inhabits a very unique ecosystem, underlines the very interesting evolutionary history of this parasite, which for now will remain unresolved.


Asunto(s)
Enfermedades de los Peces/parasitología , Peces/parasitología , Interacciones Huésped-Parásitos , Nematodos/clasificación , Nematodos/aislamiento & purificación , Infecciones por Nematodos/veterinaria , Sacos Aéreos/parasitología , Animales , Evolución Biológica , Ecosistema , Enfermedades de los Peces/epidemiología , Agua Dulce/parasitología , Secuenciación de Nucleótidos de Alto Rendimiento , Masculino , Nematodos/anatomía & histología , Nematodos/genética , Infecciones por Nematodos/epidemiología , Infecciones por Nematodos/parasitología , Nueva Zelanda/epidemiología , Filogenia , Humedales
4.
J Fish Biol ; 87(4): 967-80, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26376610

RESUMEN

The influence of capture interval on trap shyness, and temperature, rainfall and drought on capture probability (p) in 827 brown mudfish Neochanna apoda was quantified using mark-recapture models. In particular, it was hypothesized that the loss of trapping memory in marked N. apoda would lead to a capture-interval threshold required to minimize trap shyness. Neochanna apoda trap shyness approximated a threshold response to capture interval, declining rapidly with increasing capture intervals up to 16.5 days, after which p remained constant. Tests for detecting trap-dependent capture probability in Cormack-Jolly-Seber models failed to detect trap shyness in N. apoda capture histories with capture intervals averaging 16 days. This confirmed the applicability of the 16 day capture-interval threshold for mark-recapture studies. Instead, N. apoda p was positively influenced by water temperature and rainfall during capture. These results imply that a threshold capture interval is required to minimize the trade-off between the competing assumptions of population closure and p homogeneity between capture occasions in closed mark-recapture models. Moreover, environmental factors that influence behaviour could potentially confound abundance indices, and consequently abundance trends should be interpreted with caution in the face of long-term climate change, such as with global warming.


Asunto(s)
Conducta Animal , Peces/fisiología , Estrés Fisiológico , Animales , Clima , Modelos Biológicos , Probabilidad
5.
Nature ; 452(7186): 460-4, 2008 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-18368115

RESUMEN

When continents break apart, the rifting is sometimes accompanied by the production of large volumes of molten rock. The total melt volume, however, is uncertain, because only part of it has erupted at the surface. Furthermore, the cause of the magmatism is still disputed-specifically, whether or not it is due to increased mantle temperatures. We recorded deep-penetration normal-incidence and wide-angle seismic profiles across the Faroe and Hatton Bank volcanic margins in the northeast Atlantic. Here we show that near the Faroe Islands, for every 1 km along strike, 360-400 km(3) of basalt is extruded, while 540-600 km(3) is intruded into the continent-ocean transition. We find that lower-crustal intrusions are focused mainly into a narrow zone approximately 50 km wide on the transition, although extruded basalts flow more than 100 km from the rift. Seismic profiles show that the melt is intruded into the lower crust as sills, which cross-cut the continental fabric, rather than as an 'underplate' of 100 per cent melt, as has often been assumed. Evidence from the measured seismic velocities and from igneous thicknesses are consistent with the dominant control on melt production being increased mantle temperatures, with no requirement for either significant active small-scale mantle convection under the rift or the presence of fertile mantle at the time of continental break-up, as has previously been suggested for the North Atlantic Ocean.

6.
Int J Obstet Anesth ; 59: 103998, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38719764

RESUMEN

BACKGROUND: Postpartum readmission is an area of focus for improving obstetric care and reducing costs. We examined disparities in all-cause 30-day postpartum readmission by patient- and hospital-level factors in the United States. METHODS: We conducted a retrospective cohort study using 2015-2020 records from the State Inpatient Databases from four states. Generalized linear mixed models were constructed to estimate the effects of individual patient- and hospital-level factors on adjusted odds of 30-day readmission after controlling for confounders. Stratified analyses by delivery and anesthesia type (New York only) and interaction models were performed. RESULTS: Black mothers were more likely than White mothers to be readmitted within 30-days postpartum (aOR 1.57, 95% CI 1.52 to 1.61). Mothers with public insurance had increased odds of readmission compared with those with private insurance (Medicare: aOR 2.13, 95% CI 1.95 to 2.32; Medicaid: aOR 1.14, 95% CI 1.11 to 1.17). Compared with mothers in the lowest income quartile, those in the highest quartile experienced a 14% lower odds of readmission (aOR 0.86, 95% CI 0.83 to 0.89). There were no significant associations between hospital-level characteristics and readmission. Black mothers were more likely to be readmitted regardless of delivery type and most combinations of delivery and anesthesia type. Black mothers from the highest income quartile were more likely to be readmitted than White mothers from the lowest income quartile. CONCLUSION: Substantial disparities in 30-day postpartum readmissions by patient-level social factors were observed, particularly amongst Black mothers. Action is needed to address and mitigate disparities in postpartum readmission.


Asunto(s)
Readmisión del Paciente , Periodo Posparto , Humanos , Readmisión del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Femenino , Estados Unidos , Adulto , Factores de Riesgo , Embarazo , Disparidades en Atención de Salud/estadística & datos numéricos , Estudios de Cohortes , Hospitales/estadística & datos numéricos , Adulto Joven , Factores Socioeconómicos
7.
Int J Obstet Anesth ; 56: 103916, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625988

RESUMEN

BACKGROUND: Geographic-based healthcare determinants and choice of anesthesia have been shown to be associated with maternal morbidity and mortality. We explored whether differences in maternal outcomes based on maternal residence, and anesthesia type for cesarean and vaginal birth, exist. METHODS: This study was a retrospective multi-state analysis; patient residence was the predictor variable of interest and a composite binary measure of maternal end-organ injury or inpatient mortality was the primary outcome. Our secondary outcomes included a binary measure of anesthesia type for cesarean birth (general vs. neuraxial [NA]) and NA analgesia for vaginal birth (no NA vs. NA). Our predictor variable of interest was patient residency (reference category central metropolitan areas of >1 million population), fringe large metropolitan county, medium metropolitan, small metropolitan, micropolitan, and non-metropolitan or micropolitan county. RESULTS: Women residing in micropolitan (OR 1.17; 95% CI 1.09 to 1.27) and non-metropolitan or micropolitan counties (OR 1.14; 95% CI 1.04 to 1.24) had the highest adjusted increased odds of adverse maternal outcomes. Those residing in suburban, medium, and small metropolitan areas underwent general anesthesia less often during cesarean births than those residing in urban areas. Patients residing in micropolitan rural (OR 2.07; 95% CI 2.02 to 2.12) and non-metropolitan or micropolitan (2.25; 95% CI 2.16 to 2.34) counties underwent vaginal births without NA analgesia more than twice as often as those residing in urban areas. CONCLUSIONS: Rural-urban disparities in maternal end-organ damage and mortality exist and anesthesia choice may play an important role in these disparate outcomes.


Asunto(s)
Manejo del Dolor , Población Rural , Embarazo , Estados Unidos , Humanos , Femenino , Estudios Retrospectivos , Población Urbana
8.
Nature ; 442(7100): 287-90, 2006 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-16855587

RESUMEN

The determination of melt distribution in the crust and the nature of the crust-mantle boundary (the 'Moho') is fundamental to the understanding of crustal accretion processes at oceanic spreading centres. Upper-crustal magma chambers have been imaged beneath fast- and intermediate-spreading centres but it has been difficult to image structures beneath these magma sills. Using three-dimensional seismic reflection images, here we report the presence of Moho reflections beneath a crustal magma chamber at the 9 degrees 03' N overlapping spreading centre, East Pacific Rise. Our observations highlight the formation of the Moho at zero-aged crust. Over a distance of less than 7 km along the ridge crest, a rapid increase in two-way travel time of seismic waves between the magma chamber and Moho reflections is observed, which we suggest is due to a melt anomaly in the lower crust. The amplitude versus offset variation of reflections from the magma chamber shows a coincident region of higher melt fraction overlying this anomalous region, supporting the conclusion of additional melt at depth.

9.
Int J Obstet Anesth ; 50: 103543, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35461046

RESUMEN

BACKGROUND: Existing obstetric comorbidity adjustment indices were created without explicitly accounting for sociodemographic diversity in the development populations, which could lead to imprecise estimates if these indices are applied to populations different from the ones in which they were developed. The objective of this study was to validate two obstetric comorbidity indices (one using severe maternal morbidity [SMM] and one using end-organ injury or mortality) within categories of race/ethnicity. METHODS: Delivery hospitalizations from the State Inpatient Databases for Florida, Maryland, Kentucky, Washington (2015-2018) and New York (2015-2016) were analyzed. Outcomes were modeled using logistic regression by category of race/ethnicity and overall, with each model having its respective index value as the covariate. Discrimination and calibration were assessed. RESULTS: There were 1 604 203 delivery hospitalizations, among which 1.6% experienced SMM and 0.4% had SMM excluding blood transfusions. Maternal end-organ injury or mortality was identified in 0.5% of cases. For the entire patient population, the area under the receiver operating curve (AUROC) was 0.72 (95% CI 0.71 to 0.72) and 0.75 (95% CI 0.75 to 0.76) for SMM and non-transfusion SMM, respectively. The AUROC for maternal end-organ injury or death was 0.65 (95% CI 0.65 to 0.66). All scores exhibited poor calibration across racial/ethnic groups. There was no substantial variation within categories of race/ethnicity in terms of index performance. CONCLUSION: Users of these indices should consider performance data in totality when choosing a measure for obstetric comorbidity adjustment. There were no marked differences in model performance observed across race/ethnicity groups within each index.


Asunto(s)
Etnicidad , Grupos Raciales , Área Bajo la Curva , Comorbilidad , Femenino , Hospitalización , Humanos , Embarazo
10.
Int J Obstet Anesth ; 45: 74-82, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33199257

RESUMEN

BACKGROUND: Obstructive sleep apnea affects approximately 11% of women of reproductive age, although it is often undetected and untreated. Previous studies suggest an association between obstructive sleep apnea and adverse maternal outcomes. Herein, we aim to better characterize the relationship between obstructive sleep apnea and maternal outcomes. METHODS: Using the State Inpatient Databases, we performed a retrospective analysis of parturients ≥18 years old having inpatient deliveries in Florida, New York, California, Maryland, and Kentucky from 2007 to 2014. Outcomes included maternal pre-existing conditions, in-hospital mortality, maternal-fetal conditions and complications, and hospital length of stay >5 days. RESULTS: Our cohort consisted of 6 911 916 parturients of whom 4326 (0.06%) had obstructive sleep apnea. Women with obstructive sleep apnea were more likely to present with pre-existing conditions, such as obesity and pre-pregnancy diabetes. After adjusting for patient- and hospital-level confounders in our multivariate analysis, obstructive sleep apnea status was associated with an increased odds of maternal-fetal conditions and complications, including pre-eclampsia (aOR 2.05, 95% CI 1.87 to 2.26), pulmonary edema (aOR 4.73, 95% CI 2.84 to 7.89), cesarean delivery (aOR 1.96, 95% CI 1.81 to 2.11), early onset delivery (aOR 1.28, 95% CI 1.17 to 1.40), and length of stay >5 days (aOR 2.42, 95% CI 2.21 to 2.65). Obstructive sleep apnea was not significantly associated with a higher risk of in-hospital mortality. CONCLUSIONS: Pregnant women with obstructive sleep apnea have a significantly higher adjusted risk of adverse maternal outcomes compared with women without obstructive sleep apnea.


Asunto(s)
Complicaciones del Embarazo , Apnea Obstructiva del Sueño , Adolescente , Cesárea , Estudios de Cohortes , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/epidemiología , Estudios Retrospectivos , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/epidemiología , Estados Unidos/epidemiología
11.
Int J Obstet Anesth ; 47: 103160, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33931312

RESUMEN

BACKGROUND: High Black-serving delivery units and high hospital safety-net burden have been associated with poorer patient outcomes. We examine these hospital-level factors and their association with severe maternal morbidity (SMM), independently and as effect modifiers of patient-level factors. METHODS: Using the 2007-2014 State Inpatient Databases (Florida, New York, California, Maryland, Kentucky), we analyzed delivery hospitalizations. We constructed generalized linear mixed models with patient- and hospital-level variables (Black-serving delivery units: high: top 5th percentile; medium: 5th-25th percentile; low: bottom 75th percentile; hospital safety-net burden status defined by insurance status) and report adjusted odds ratios (aOR) and 99% confidence intervals (CI). We repeated our mixed models with stratification and interaction analysis. RESULTS: 6 879 332 delivery hospitalizations were included in the analysis. Deliveries at high (aOR 1.83; 99% CI 1.34 to2.50) or medium (aOR 1.27; 99% CI 1.10 to 1.46) Black-serving delivery units were more likely to have SMM than deliveries at low Black-serving delivery units. Hospital safety-net burden was not significantly associated with SMM. In stratified models by hospital category, deliveries of Black women were associated with an increase in SMM compared with deliveries of White women in all hospital categories. In interaction models, Black women giving birth in high Black-serving delivery units had more than twice the odds of White women in low Black-serving delivery units of experiencing SMM (aOR 2.42; 99% CI 1.90 to 3.08). CONCLUSION: The patient racial/ethnic composition of the delivery unit is associated with adjusted-odds of SMM, both independently and interactively with individual patient race.


Asunto(s)
Negro o Afroamericano , Población Blanca , Etnicidad , Femenino , Hospitales , Humanos , Parto , Embarazo
12.
Science ; 182(4116): 1020-1, 1973 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-17833788

RESUMEN

Predictions of Jupiter's electron and proton radiation belts are based mainly on decimeter observations of 1966 and 1968. Extensive calculations modeling radial diffusion of particles inward from the solar wind and electron synchrotron radiation are used to relate the predictions and observations.

13.
Science ; 244(4903): 451-4, 1989 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-17807612

RESUMEN

Gamma rays at energies of 0.3 to 8 megaelectron volts (MeV) were detected on 15 April 1988 from four nuclear-powered satellites including Cosmos 1900 and Cosmos 1932 as they flew over a double Compton gamma-ray telescope. The observations occurred as the telescope, flown from a balloon at an altitude of 35 kilometers from Alice Springs, Australia, searched for celestial gamma-ray sources. The four transient signals were detected in 30 hours of data. Their time profiles show maxima with durations of (21 +/- 1) and (27 +/- 1) seconds (half-width at half maximum) for the lower two satellites and (85 +/- 5) and (113 +/- 7) seconds for the remaining two. Their durations place the origin of the two shorter signals at orbital radii of 260(+40)(-60) and 260 +/- 60 km above the earth and the two longer at 800(+100)(-300) and 800(+250)(-300) kilometers. Their luminosities for energies >0.3 MeV are then (6.1 +/- 1.5) x 10(15), (3.9 +/- 1.0) x 10(15), (1.10 +/- 0.28) x 10(16), and (1.30 +/- 0.32) x 10(16) photons per second. The imaging of the strongest signal indicates a southeastern direction passing nearly overhead. The energy spectrum can be fit to an exponential with index 2.4 +/- 1.4. These transient events add to the already large backgrounds for celestial gamma ray sources.

14.
Sci Adv ; 5(11): eaax6642, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31807704

RESUMEN

Seismic noise interferometry is an exciting technique for studying volcanoes, providing a continuous measurement of seismic velocity changes (dv/v), which are sensitive to magmatic processes that affect the surrounding crust. However, understanding the exact mechanisms causing changes in dv/v is often difficult. We present dv/v measurements over 10 years in central Iceland, measured using single-station cross-component correlation functions from 51 instruments across a range of frequency bands. We observe a linear correlation between changes in dv/v and volumetric strain at stations in regions of both compression and dilatation associated with the 2014 Bárðarbunga-Holuhraun dike intrusion. Furthermore, a clear seasonal cycle in dv/v is modeled as resulting from elastic and poroelastic responses to changing snow thickness, atmospheric pressure, and groundwater level. This study comprehensively explains variations in dv/v arising from diverse crustal stresses and highlights the importance of deformation modeling when interpreting dv/v, with implications for volcano and environmental monitoring worldwide.

16.
Int J Obstet Anesth ; 60: 104216, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-39018740
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