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1.
Glob Chang Biol ; 30(1): e17065, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273564

RESUMEN

Anthropogenic warming is altering species abundance, distribution, physiology, and more. How changes observed at the species level alter emergent community properties is an active and urgent area of research. Trait-based ecology and regime shift theory provide complementary ways to understand climate change impacts on communities, but these two bodies of work are only rarely integrated. Lack of integration handicaps our ability to understand community responses to warming, at a time when such understanding is critical. Therefore, we advocate for merging trait-based ecology with regime shift theory. We propose a general set of principles to guide this merger and apply these principles to research on marine communities in the rapidly warming North Atlantic. In our example, combining trait distribution and regime shift analyses at the community level yields greater insight than either alone. Looking forward, we identify a clear need for expanding quantitative approaches to collecting and merging trait-based and resilience metrics in order to advance our understanding of climate-driven community change.


Asunto(s)
Cambio Climático , Ecología , Ecosistema
2.
Vasc Endovascular Surg ; 56(2): 201-207, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34592855

RESUMEN

We present a 74-year-old gentleman, who presented with foot ischaemia requiring bilateral amputation in the absence of radiological signs of occlusive peripheral arterial disease. He was found to have COVID-19 pneumonitis and concurrent arterial and venous thromboemboli despite no initial respiratory symptoms or signs, nor pre-existing risk factors for cardiovascular disease. Patients who present with foot ischaemia with or without respiratory symptoms or signs warrant a high index of suspicion for COVID-19 infection, particularly in those with no predisposing risk factors.


Asunto(s)
COVID-19 , Enfermedad Arterial Periférica , Tromboembolia Venosa , Anciano , Humanos , Isquemia/diagnóstico por imagen , Isquemia/etiología , Extremidad Inferior , Masculino , Enfermedad Arterial Periférica/complicaciones , Enfermedad Arterial Periférica/diagnóstico por imagen , SARS-CoV-2 , Dedos del Pie , Resultado del Tratamiento
3.
Ecol Evol ; 10(20): 11022-11030, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33144945

RESUMEN

Conventional observations show spiny dogfish (Squalus acanthius Linnaeus) rarely eat Atlantic cod (Gadus morhua Linnaeus; 0.02% of stomachs) in the northwestern Atlantic Ocean. Critics express concern that digestion may limit species-level prey identification, and with recovery from overfishing, dogfish populations may be suppressing cod by competition or predation. This study applied a real-time PCR TaqMan assay to identify cod in dogfish stomachs collected by cooperating fishing boats during normal trawling operations (May 2014-May 2015; Gulf of Maine, Georges Bank). Conventional methods observed 51 different prey taxa and nearly 1,600 individual prey items, but no cod were observed. Cod DNA was detected in 31 (10.5%) of the dogfish stomachs, with a higher percentage of these from the homogenate of amorphous, well-digested prey and stomach fluids (20 stomachs or 65%) than from discrete animal tissues (11 stomachs or 35%). Re-examination of photographs of these 11 tissue samples revealed one whole, partially digested fish that could be recognized in hindsight as cod. Cod DNA was observed in dogfish stomachs year round: in January (1 of 1 trip), February (1 of 1), May (1 of 3), June (0 of 1), July (3 of 4), August (1 of 2), and October (3 of 3). Although these data suggest higher interaction rates between dogfish and cod than previously observed, addressing the population consequences of this predator-prey relationship requires a robust sampling design, estimates of digestion rates by dogfish to account for complete degradation of DNA sequences, and consideration for dogfish scavenging during fishing operations.

4.
Psychiatry Res ; 257: 400-405, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28830024

RESUMEN

Neurocognitive disturbance with subjectively-impaired concentration and memory is a common, disabling symptom reported by patients with chronic fatigue syndrome (CFS). We recently reported preliminary evidence for benefits of cognitive remediation as part of an integrated cognitive-behavioral therapy (CBT)/ graded exercise therapy (GET) program. Here, we describe a contemporaneous, case-control trial evaluating the effectiveness of an online cognitive remediation training program (cognitive exercise therapy; CET) in addition to CBT/GET (n=36), compared to CBT/GET alone (n=36). The study was conducted in an academic, tertiary referral outpatient setting over 12 weeks (11 visits) with structured, home-based activities between visits. Participants self-reported standardized measures of symptom severity and functional status before and after the intervention. Those in the CET arm also completed standardized neurocognitive assessment before, and following, treatment. The addition of formal CET led to significantly greater improvements in self-reported neurocognitive symptoms compared to CBT/GET alone. Subjective improvement was predicted by CET group and lower baseline mood disturbance. In the CET group, significant improvements in objectively-measured executive function, processing speed, and working memory were observed. These subjective and objective performance improvements suggest that a computerized, home-based cognitive training program may be an effective intervention for patients with CFS, warranting randomized controlled trials.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Remediación Cognitiva/métodos , Terapia por Ejercicio/métodos , Síndrome de Fatiga Crónica/terapia , Adolescente , Adulto , Anciano , Síndrome de Fatiga Crónica/fisiopatología , Síndrome de Fatiga Crónica/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoinforme , Resultado del Tratamiento , Adulto Joven
5.
Foods ; 6(7)2017 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-28737681

RESUMEN

Dark green leafy vegetables (DGLVs) are considered as important sources of iron and vitamin A. However, iron concentration may not indicate bioaccessibility. The objectives of this study were to compare the nutrient content and iron bioaccessibility of five sweet potato cultivars, including three orange-fleshed types, with other commonly consumed DGLVs in Ghana: cocoyam, corchorus, baobab, kenaf and moringa, using the in vitro digestion/Caco-2 cell model. Moringa had the highest numbers of iron absorption enhancers on an "as-would-be-eaten" basis, ß-carotene (14169 µg/100 g; p < 0.05) and ascorbic acid (46.30 mg/100 g; p < 0.001), and the best iron bioaccessibility (10.28 ng ferritin/mg protein). Baobab and an orange-fleshed sweet potato with purplish young leaves had a lower iron bioaccessibility (6.51 and 6.76 ng ferritin/mg protein, respectively) compared with that of moringa, although these three greens contained similar (p > 0.05) iron (averaging 4.18 mg/100 g) and ß-carotene levels. The ascorbic acid concentration of 25.50 mg/100 g in the cooked baobab did not enhance the iron bioaccessibility. Baobab and the orange-fleshed sweet potato with purplish young leaves contained the highest levels of total polyphenols (1646.75 and 506.95 mg Gallic Acid Equivalents/100 g, respectively; p < 0.001). This suggests that iron bioaccessibility in greens cannot be inferred based on the mineral concentration. Based on the similarity of the iron bioaccessibility of the sweet potato leaves and cocoyam leaf (a widely-promoted "nutritious" DGLV in Ghana), the former greens have an added advantage of increasing the dietary intake of provitamin A.

6.
J Vasc Surg ; 65(1): 263-266, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28010865

RESUMEN

We report a modified operative technique termed partial eversion carotid endarterectomy (PECE). During a 9-year period (2006-2015), 352 patients underwent PECE. Indications for surgery, intraoperative details, and outcomes were recorded. The initial 185 patients had carotid duplex ultrasound imaging at 6 weeks and then at 6, 12, and 24 months. Subsequent patients had carotid imaging at 4 to 6 weeks. Indications included stroke (76), transient ischemic attack (153), and amaurosis fugax (33); 58 patients were asymptomatic, and 32 patients had surgery before cardiac surgery. Median clamp time was 14 minutes (interquartile range, 11.5-17 minutes). Median total operation time was 41 minutes (interquartile range, 31-72 minutes). Outcomes included four transient ischemic attacks (1.2%), five strokes (1.4%), and two deaths at 30 days (0.5%). No significant cranial nerve injuries or carotid restenosis was detected during follow-up. PECE is technically straightforward, with outcomes comparable to those of current operative techniques. Its advantages included reduced operative and carotid clamping time.


Asunto(s)
Estenosis Carotídea/cirugía , Endarterectomía Carotidea/métodos , Anciano , Amaurosis Fugax/etiología , Enfermedades Asintomáticas , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/mortalidad , Angiografía por Tomografía Computarizada , Endarterectomía Carotidea/efectos adversos , Endarterectomía Carotidea/mortalidad , Femenino , Humanos , Ataque Isquémico Transitorio/etiología , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Prospectivos , Factores de Riesgo , Accidente Cerebrovascular/etiología , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía Doppler Dúplex
7.
PLoS One ; 11(10): e0164203, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27716845

RESUMEN

Reports of American shad fecundity identify two important themes regarding egg production in fishes. First, geographic variation occurs and is biologically meaningful. Shad annual fecundity decreases with increasing latitude, but predicted lifetime fecundity does not, because of a counter-gradient of survival probability, all of which can explain the adaptive significance of natal homing. Second, the appropriate method of measuring fecundity depends on the pattern of oocyte development. Historically, the relatively simple determinate-fecundity method was used; however, a recent study in a Virginia river indicates that this method may be biased, requiring the more complicated indeterminate method. We address both themes with collections from the 2015 shad spawning run in the Connecticut River, USA. Criteria for using a determinate method were satisfied for this northern population: 1) a size gap evident in the oocyte size frequency distribution, indicating group-synchronous development of yolked oocytes; 2) a decline, early in spawning, in the standing stock of yolked oocytes; and 3) low levels of atresia at the end of spawning. The determinate-method estimate of American shad annual (2015) fecundity (303,000 ± 73,400; mean ± sd) overlapped historic estimates for this and a neighboring river. The indeterminate-method estimate of annual (2015) fecundity (311,500 ± 4,500 sd) was not significantly different from the determinate-method estimate (Student's t-test, P > 0.05). In contrast, indeterminate-method estimates of annual fecundity for a Virginia population were twice as high as that measured by the determinate method in the past. This can all be explained by fundamentally different patterns of oogenesis (i.e., group synchrony versus asynchrony with respect to yolk development) at different latitudes. American shad, which is distributed within its native range from the Canadian maritimes to Florida, USA (50-30°N), may be particularly well suited to evaluate intra-specific variation in oocyte development, a relatively unexplored life history trait.


Asunto(s)
Fertilidad/fisiología , Peces/crecimiento & desarrollo , Oocitos/crecimiento & desarrollo , Animales , Femenino , New England , Oogénesis/fisiología , Reproducción/fisiología , Estaciones del Año , Estados Unidos
8.
BMC Res Notes ; 9: 251, 2016 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-27129470

RESUMEN

BACKGROUND: The sheepshead (Archosargus probatocephalus) is found in nearshore waters from Nova Scotia, Canada, to Rio Grande do Sul, Brazil. In the southeastern United States two subspecies are recognized based on a number of meristic characters, primarily counts of melanistic pigment bars. The only previous study based on mtDNA control-region sequence found limited divergence between those subspecies and isolation by distance among 15 locations from Florida (Atlantic Ocean) to Texas (Gulf of Mexico). In the same study, using six sparid microsatellite markers, Bayesian analysis showed that the Gulf and Atlantic sheepshead form a single population. To reinvestigate the fine-scale genetic population structure and examine genetic support for the morphologically classified subspecies, a set of species-specific microsatellite markers was needed. FINDINGS: Here we report on 24 polymorphic microsatellite markers isolated from sheepshead and screened in 57 specimens from the Indian River, Florida. The average number of alleles per locus was 13.1; mean observed and expected heterozygosities were 0.68 and 0.73, respectively. Nine sparid markers screened for the same specimens showed an average of 8.6 alleles per locus; mean observed and expected heterozygosities were 0.46 and 0.55, respectively. CONCLUSIONS: The polymorphic markers reported here can be used to search for genetic evidence for the morphologically defined subspecies, to elucidate the fine-scale genetic population structure of this broadly distributed coastal species, and to provide an opportunity to directly compare results of population delineation between nonspecific and species-specific markers.


Asunto(s)
ADN/genética , ADN/aislamiento & purificación , Sitios Genéticos , Genética de Población , Repeticiones de Microsatélite/genética , Perciformes/genética , Polimorfismo Genético , Animales
9.
Eur J Nutr ; 54(8): 1345-52, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25526967

RESUMEN

PURPOSE: Iron deficiency anaemia (IDA) is a global public health problem. Treatment with the standard of care ferrous iron salts may be poorly tolerated, leading to non-compliance and ineffective correction of IDA. Employing supplements with higher bioavailability might permit lower doses of iron to be used with fewer side effects, thus improving treatment efficacy. Here, we compared the iron bioavailability of ferrous sulphate tablets with alternative commercial iron products, including three liquid-based supplements. METHODS: Iron bioavailability was measured using Caco-2 cells with ferritin formation as a surrogate marker for iron uptake. Statistical analysis was performed using one-way ANOVA followed by either Dunnett's or Tukey's multiple comparisons tests. RESULTS: Spatone Apple(®) (a naturally iron-rich mineral water with added ascorbate) and Iron Vital F(®) (a synthetic liquid iron supplement) had the highest iron bioavailability. There was no statistical difference between iron uptake from ferrous sulphate tablets, Spatone(®) (naturally iron-rich mineral water alone) and Pregnacare Original(®) (a multimineral/multivitamin tablet). CONCLUSION: In our in vitro model, naturally iron-rich mineral waters and synthetic liquid iron formulations have equivalent or better bioavailability compared with ferrous iron sulphate tablets. If these results are confirmed in vivo, this would mean that at-risk groups of IDA could be offered a greater choice of more bioavailable and potentially better tolerated iron preparations.


Asunto(s)
Suplementos Dietéticos , Hierro de la Dieta/farmacocinética , Anemia Ferropénica/tratamiento farmacológico , Disponibilidad Biológica , Células CACO-2 , Ferritinas/metabolismo , Compuestos Ferrosos/administración & dosificación , Compuestos Ferrosos/farmacocinética , Humanos , Hierro de la Dieta/administración & dosificación
10.
MSMR ; 21(2): 2-4; comment, 5-6, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24601683

RESUMEN

Emergency whole blood transfusions may increase the risk of transmitting bloodborne pathogens, including human T-lymphotropic viruses (HTLVs). U.S. military personnel with any medical encounter for HTLV infection during 2000-2013;2008 were identified from surveillance data. Using both inclusive and restrictive case definitions, the incidence of diagnoses of HTLV infection was analyzed in relation to demographic factors and prior deployment. There were 247 "possible" cases of HTLV infection identified, or 1.88 cases per 100,000 person-years (p-yrs) (95% CI 1.66, 2.13). Seventy of these met the restrictive definition, translating to a rate of 0.53 per 100,000 p-yrs (95% CI 0.42, 0.67). Under the restrictive definition, a higher rate was noted among females versus males (RR 2.37; 95% CI 1.41, 3.98), service members with a healthcare occupation versus those who are primarily trained to engage in combat (RR 2.54; 95% CI 1.06, 6.10), and service members with any deployment experience (RR 8.98; 95% CI 5.61, 14.37). These findings, and a prior military case report of transfusion-transmitted HTLV-I, suggest a need to better define the epidemiology of HTLV in U.S. military personnel to further ensure emergency transfusion safety.


Asunto(s)
Infecciones por Deltaretrovirus/epidemiología , Personal Militar , Adolescente , Adulto , Infecciones por Deltaretrovirus/transmisión , Femenino , Humanos , Masculino , Estados Unidos/epidemiología
11.
Mol Ecol Resour ; 12(4): 779-81, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22642264

RESUMEN

This article documents the addition of 171 microsatellite marker loci and 27 pairs of single nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bombus pauloensis, Cephalorhynchus heavisidii, Cercospora sojina, Harpyhaliaetus coronatus, Hordeum vulgare, Lachnolaimus maximus, Oceanodroma monteiroi, Puccinia striiformis f. sp. tritici, Rhea americana, Salmo salar, Salmo trutta, Schistocephalus solidus, Sousa plumbea and Tursiops aduncus. These loci were cross-tested on the following species: Aquila heliaca, Bulweria bulwerii, Buteo buteo, Buteo swainsoni, Falco rusticolus, Haliaeetus albicilla, Halobaena caerulea, Hieraaetus fasciatus, Oceanodroma castro, Puccinia graminis f. sp. Tritici, Puccinia triticina, Rhea pennata and Schistocephalus pungitii. This article also documents the addition of 27 sequencing primer pairs for Puffinus baroli and Bulweria bulwerii and cross-testing of these loci in Oceanodroma castro, Pelagodroma marina, Pelecanoides georgicus, Pelecanoides urinatrix, Thalassarche chrysostoma and Thalassarche melanophrys.


Asunto(s)
Bases de Datos Genéticas , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple , Ecología , Marcadores Genéticos
12.
Transfusion ; 51(3): 473-85, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20946199

RESUMEN

BACKGROUND: Current US military clinical practice guidelines permit emergency transfusions of non-Food and Drug Administration (FDA)-compliant freshly collected blood products in theaters of war. This investigation aimed to characterize the risks of transfusion-transmitted infections (TTIs) associated with battlefield transfusions of non-FDA-compliant blood products. STUDY DESIGN AND METHODS: US Service members who received emergency transfusion products in Iraq and Afghanistan (March 1, 2002-September 30, 2007) were tested for hepatitis C virus (HCV), human immunodeficiency virus (HIV), and hepatitis B virus (HBV) infections using reposed pre- and posttransfusion sera. Selected regions of viral genomes from epidemiologically linked infected recipients and their donors were sequenced and compared. RESULTS: Of 761 US Service members who received emergency transfusion products, 475 were tested for HCV, 472 for HIV, and 469 for HBV. One transfusion-transmitted HCV infection (incidence rate of 2.1/1000 persons) was identified. The pretransfusion numbers (prevalence per 1000 persons) were HCV-four (8/1000), HIV-zero (0/1000), chronic HBV-two (4 /1000), and naturally immune (antibody to HBV core antigen)-nine (19/1000). CONCLUSION: One HCV TTI was determined to be associated with emergency blood product use. The pretransfusion HCV and HBV prevalence in transfusion recipients, themselves members of the potential donor population, indicates better characterization of the deployed force's actual donor population, and further investigations of the TTI prevalence in these donors are needed. These data will inform countermeasure development and clinical decision making.


Asunto(s)
Guerra de Irak 2003-2011 , Personal Militar , Transfusión de Plaquetas/efectos adversos , Reacción a la Transfusión , Virosis/transmisión , Adulto , Anciano , Secuencia de Bases , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Hepatitis B/epidemiología , Hepatitis B/transmisión , Hepatitis C/epidemiología , Hepatitis C/transmisión , Humanos , Irak/epidemiología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Virosis/epidemiología
13.
Biol Bull ; 204(1): 57-67, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12588745

RESUMEN

Analyses of life-history data show that both the size-specific batch fecundities and the age-specific spawning frequencies differ for two halfbeak species, Hemiramphus brasiliensis, the ballyhoo, and H. balao, the balao. Halfbeak ages were determined from sectioned otoliths; histological data was used to describe oocyte development and estimate spawning frequency; and batch fecundity was measured from counts of whole oocytes in final maturation. Hemiramphus brasiliensis lived longer (4 versus 2 years) and had a higher survival rate (14.9% versus 7.5% annually) than H. balao did. Of the two species the larger and longer-lived congener, H. brasiliensis, reached sexual maturity at a larger size (fork length 198 versus 160 mm). The spawning period of age-0 females was strongly related to season, whereas spawning by older females occurred throughout the year. Reproduction by both species peaked during late spring or early summer, and all mature females were spawning daily during April (H. brasiliensis) or June (H. balao). This is the first demonstration of iteroparity for the family Hemiramphidae. H. brasiliensis had a lower batch fecundity (about 1164 versus 3743 hydrated oocytes for a 100-g female) than H. balao did. Such low batch fecundities are typical of the order Beloniformes, but quite different from those of other fishes that live in association with coral reef habitats. H. balao's higher batch fecundity is consistent with the life-history theory that predicts higher numbers of eggs for shorter-lived species; this is possible because H. balao produces smaller hydrated oocytes than H. brasiliensis (modal diameter about 1.6 versus 2.4 mm). The high spawning frequency of Hemiramphus species compensates for their low batch fecundity. The annual fecundity of both species is similar to that of other reef fish species, after adjusting for body size and spawning frequency. The lifetime fecundity of H. balao was very similar to that of H. brasiliensis, after accounting for the differences in survival for each species. This suggests a fine tuning of different reproductive traits over the entire life cycle that results in roughly equivalent lifetime fecundity for both species.


Asunto(s)
Fertilidad , Peces/fisiología , Animales , Especificidad de la Especie
14.
Biol Psychiatry ; 51(6): 474-9, 2002 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11922882

RESUMEN

BACKGROUND: Repetitive transcranial magnetic stimulation has been demonstrated in humans as well as in animal models to have an antidepressant effect, but the optimal frequency of stimulation is not known. We examined this question in a rat model of depression. METHODS: Young male Sprague-Dawley rats were allocated to two placebo (restraint and sham transcranial magnetic stimulation), one active control (imipramine), and four transcranial magnetic stimulation groups at 1, 5, 15 and 25 Hz and 1000 stimuli each. The Porsolt Swim Test was performed on day 1 (experiment 1). In an extension (experiment 2), the treatments were repeated on days 2 through 5, and the Swim Test repeated on days 3, 5, and 7. RESULTS: After one treatment session, all transcranial magnetic stimulation groups had significantly reduced immobility times compared with sham stimulation (p =.000), but the higher frequencies (15 and 25 Hz) did not differ significantly from lower (1 and 5 Hz) frequencies. After three sessions, all transcranial magnetic stimulation groups were different from placebo, and the rapid transcranial magnetic stimulation groups had lower immobility times than the slow transcranial magnetic stimulation groups (p =.035). After five sessions, only 15- and 25-Hz groups were different from control, and on day 7, only the 25-Hz group had reduced immobility. There was an overall difference between fast and slow transcranial magnetic stimulation (p =.010), and 1 Hz was different from the other three transcranial magnetic stimulation conditions (p =.016). CONCLUSIONS: Repetitive transcranial magnetic stimulation reduces immobility time in the Forced Swim Test model of depression, suggesting an antidepressant effect, which is evident at a range (1-25 Hz) of frequencies. With repeated administration, the findings suggest that the antidepressant effect of the higher frequencies, as for imipramine, is likely to be sustained, although the model used for this (i.e., repeating the Swim Test) requires further validation.


Asunto(s)
Depresión/fisiopatología , Campos Electromagnéticos , Motivación , Animales , Nivel de Alerta/efectos de los fármacos , Nivel de Alerta/fisiología , Desamparo Adquirido , Imipramina/farmacología , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Ratas , Ratas Sprague-Dawley , Natación
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