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1.
Nature ; 520(7547): 341-4, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25855298

RESUMEN

Continuing degradation of coral reef ecosystems has generated substantial interest in how management can support reef resilience. Fishing is the primary source of diminished reef function globally, leading to widespread calls for additional marine reserves to recover fish biomass and restore key ecosystem functions. Yet there are no established baselines for determining when these conservation objectives have been met or whether alternative management strategies provide similar ecosystem benefits. Here we establish empirical conservation benchmarks and fish biomass recovery timelines against which coral reefs can be assessed and managed by studying the recovery potential of more than 800 coral reefs along an exploitation gradient. We show that resident reef fish biomass in the absence of fishing (B0) averages ∼1,000 kg ha(-1), and that the vast majority (83%) of fished reefs are missing more than half their expected biomass, with severe consequences for key ecosystem functions such as predation. Given protection from fishing, reef fish biomass has the potential to recover within 35 years on average and less than 60 years when heavily depleted. Notably, alternative fisheries restrictions are largely (64%) successful at maintaining biomass above 50% of B0, sustaining key functions such as herbivory. Our results demonstrate that crucial ecosystem functions can be maintained through a range of fisheries restrictions, allowing coral reef managers to develop recovery plans that meet conservation and livelihood objectives in areas where marine reserves are not socially or politically feasible solutions.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/tendencias , Arrecifes de Coral , Ecosistema , Explotaciones Pesqueras/métodos , Explotaciones Pesqueras/estadística & datos numéricos , Peces/fisiología , Animales , Biodiversidad , Biomasa , Conservación de los Recursos Naturales/estadística & datos numéricos , Explotaciones Pesqueras/normas , Herbivoria , Dinámica Poblacional , Conducta Predatoria , Factores de Tiempo
2.
J Anim Ecol ; 88(10): 1564-1574, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31264204

RESUMEN

Coral reef food webs are complex, vary spatially and remain poorly understood. Certain large predators, notably sharks, are subsidized by pelagic production on outer reef slopes, but how widespread this dependence is across all teleost fishery target species and within atolls is unclear. North Malé Atoll (Maldives) includes oceanic barrier as well as lagoonal reefs. Nine fishery target predators constituting ca. 55% of the local fishery target species biomass at assumed trophic levels 3-5 were selected for analysis. Data were derived from carbon (δ13 C), nitrogen (δ15 N) and sulphur (δ34 S) stable isotopes from predator white dorsal muscle samples, and primary consumer species representing production source end-members. Three-source Bayesian stable isotope mixing models showed that uptake of pelagic production extends throughout the atoll, with predatory fishes showing equal planktonic reliance between inner and outer edge reefs. Median plankton contribution was 65%-80% for all groupers and 68%-88% for an emperor, a jack and snappers. Lagoonal and atoll edge predators are equally at risk from anthropogenic and climate-induced changes, which may impact the linkages they construct, highlighting the need for management plans that transcend the boundaries of this threatened ecosystem.


Asunto(s)
Arrecifes de Coral , Ecosistema , Animales , Teorema de Bayes , Peces , Islas del Oceano Índico , Masculino , Océanos y Mares , Prevalencia
3.
J Fish Biol ; 94(4): 585-594, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30779136

RESUMEN

The grazing behaviour of two Caribbean parrotfish, a fished species, the stoplight parrotfish Sparisoma viride and a non-fished species, the striped parrotfish Scarus iseri, were studied in the presence (fished site) and absence (marine reserve) of chronic spearfishing activity. Diurnal feeding periodicity did not differ between the sites in either species: roving individuals had significantly higher bite rates in the afternoon, while territorial individuals foraged consistently throughout the day. Mean bite rate varied between sites in both species. Abundance, biomass and bite rates of S. viride were all significantly higher within the reserve, except for roving S. viride which had a higher mean bite rate in the afternoon outside the reserve compared with within it, attributable to maximisation of feeding in the afternoon when fishing risk was lower. Scarus iseri mean abundance and bite rate were greater outside the reserve, potentially because reduction in large territorial herbivores allowed S. iseri to feed more rapidly. By reducing the grazing potential of the remaining S. viride individuals the effect of fishing is greater than would be predicted from biomass changes alone. Less grazing by S. viride would not be compensated for by the increase in grazing by S. iseri because the latter feeds on different algae. Spearfishing of key parrotfish species reduces grazing potential directly by extraction and indirectly by changing behaviour.


Asunto(s)
Conducta Animal , Arrecifes de Coral , Peces/fisiología , Animales , Biomasa , Región del Caribe , Herbivoria , Densidad de Población , Territorialidad
4.
Ecology ; 99(2): 450-463, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29328509

RESUMEN

Refuge availability and fishing alter predator-prey interactions on coral reefs, but our understanding of how they interact to drive food web dynamics, community structure and vulnerability of different trophic groups is unclear. Here, we apply a size-based ecosystem model of coral reefs, parameterized with empirical measures of structural complexity, to predict fish biomass, productivity and community structure in reef ecosystems under a broad range of refuge availability and fishing regimes. In unfished ecosystems, the expected positive correlation between reef structural complexity and biomass emerges, but a non-linear effect of predation refuges is observed for the productivity of predatory fish. Reefs with intermediate complexity have the highest predator productivity, but when refuge availability is high and prey are less available, predator growth rates decrease, with significant implications for fisheries. Specifically, as fishing intensity increases, predators in habitats with high refuge availability exhibit vulnerability to over-exploitation, resulting in communities dominated by herbivores. Our study reveals mechanisms for threshold dynamics in predators living in complex habitats and elucidates how predators can be food-limited when most of their prey are able to hide. We also highlight the importance of nutrient recycling via the detrital pathway, to support high predator biomasses on coral reefs.


Asunto(s)
Arrecifes de Coral , Ecosistema , Animales , Explotaciones Pesqueras , Peces , Cadena Alimentaria , Conducta Predatoria
5.
J Exp Biol ; 221(Pt 4)2018 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-29212845

RESUMEN

A central issue for understanding locomotion of vertebrates is how muscle activity and movements of their segmented axial structures are coordinated, and snakes have a longitudinal uniformity of body segments and diverse locomotor behaviors that are well suited for studying the neural control of rhythmic axial movements. Unlike all other major modes of snake locomotion, rectilinear locomotion does not involve axial bending, and the mechanisms of propulsion and modulating speed are not well understood. We integrated electromyograms and kinematics of boa constrictors to test Lissmann's decades-old hypotheses of activity of the costocutaneous superior (CCS) and inferior (CCI) muscles and the intrinsic cutaneous interscutalis (IS) muscle during rectilinear locomotion. The CCI was active during static contact with the ground as it shortened and pulled the axial skeleton forward relative to both the ventral skin and the ground during the propulsive phase. The CCS was active during sliding contact with the ground as it shortened and pulled the skin forward relative to both the skeleton and the ground during the recovery phase. The IS shortened the ventral skin, and subsequent isometric activity kept the skin stiff and shortened during most of static contact while overlapping extensively with CCI activity. The concentric activity of the CCI and CCS supported Lissmann's predictions. Contrary to Lissmann, the IS had prolonged isometric activity, and the time when it shortened was not consistent with providing propulsive force. Decoupling propulsion from axial bending in rectilinear locomotion may have facilitated economical locomotion of early snakes in subterranean tunnels.


Asunto(s)
Boidae/fisiología , Locomoción , Músculo Esquelético/fisiología , Animales , Fenómenos Biomecánicos , Electromiografía
6.
J Exp Biol ; 218(Pt 24): 3978-86, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26677261

RESUMEN

Depending on animal size, shape, body plan and behaviour, variation in surface structure can affect the speed and ease of locomotion. The slope of branches and the roughness of bark both vary considerably, but their combined effects on the locomotion of arboreal animals are poorly understood. We used artificial branches with five inclines and five peg heights (≤40 mm) to test for interactive effects on the locomotion of three snake species with different body shapes. Unlike boa constrictors (Boa constrictor), corn snakes (Pantherophis guttatus) and brown tree snakes (Boiga irregularis) can both form ventrolateral keels, which are most pronounced in B. irregularis. Increasing peg height up to 10 mm elicited more of the lateral undulatory behaviour (sliding contact without gripping) rather than the concertina behaviour (periodic static gripping) and increased the speed of lateral undulation. Increased incline: (1) elicited more concertina locomotion, (2) decreased speed and (3) increased the threshold peg height that elicited lateral undulation. Boiga irregularis was the fastest species, and it used lateral undulation on the most surfaces, including a vertical cylinder with pegs only 1 mm high. Overall, B. constrictor was the slowest and used the most concertina locomotion, but this species climbed steep, smooth surfaces faster than P. guttatus. Our results illustrate how morphology and two different aspects of habitat structure can have interactive effects on organismal performance and behaviour. Notably, a sharper keel facilitated exploiting shorter protrusions to prevent slipping and provide propulsion, which became increasingly important as surface steepness increased.


Asunto(s)
Boidae/anatomía & histología , Boidae/fisiología , Colubridae/anatomía & histología , Colubridae/fisiología , Locomoción , Animales , Conducta Animal , Fenómenos Biomecánicos , Ecosistema , Propiedades de Superficie , Árboles
7.
J Anim Ecol ; 84(6): 1678-89, 2015 11.
Artículo en Inglés | MEDLINE | ID: mdl-26344713

RESUMEN

There has been ongoing flattening of Caribbean coral reefs with the loss of habitat having severe implications for these systems. Complexity and its structural components are important to fish species richness and community composition, but little is known about its role for other taxa or species-specific responses. This study reveals the importance of reef habitat complexity and structural components to different taxa of macrofauna, total species richness, and individual coral and fish species in the Caribbean. Species presence and richness of different taxa were visually quantified in one hundred 25-m(2) plots in three marine reserves in the Caribbean. Sampling was evenly distributed across five levels of visually estimated reef complexity, with five structural components also recorded: the number of corals, number of large corals, slope angle, maximum sponge and maximum octocoral height. Taking advantage of natural heterogeneity in structural complexity within a particular coral reef habitat (Orbicella reefs) and discrete environmental envelope, thus minimizing other sources of variability, the relative importance of reef complexity and structural components was quantified for different taxa and individual fish and coral species on Caribbean coral reefs using boosted regression trees (BRTs). Boosted regression tree models performed very well when explaining variability in total (82·3%), coral (80·6%) and fish species richness (77·3%), for which the greatest declines in richness occurred below intermediate reef complexity levels. Complexity accounted for very little of the variability in octocorals, sponges, arthropods, annelids or anemones. BRTs revealed species-specific variability and importance for reef complexity and structural components. Coral and fish species occupancy generally declined at low complexity levels, with the exception of two coral species (Pseudodiploria strigosa and Porites divaricata) and four fish species (Halichoeres bivittatus, H. maculipinna, Malacoctenus triangulatus and Stegastes partitus) more common at lower reef complexity levels. A significant interaction between country and reef complexity revealed a non-additive decline in species richness in areas of low complexity and the reserve in Puerto Rico. Flattening of Caribbean coral reefs will result in substantial species losses, with few winners. Individual structural components have considerable value to different species, and their loss may have profound impacts on population responses of coral and fish due to identity effects of key species, which underpin population richness and resilience and may affect essential ecosystem processes and services.


Asunto(s)
Antozoos/fisiología , Biodiversidad , Arrecifes de Coral , Peces/fisiología , Animales , Antillas Holandesas , Densidad de Población , Puerto Rico , San Vicente y las Grenadinas
8.
Eur J Nucl Med Mol Imaging ; 41(10): 1861-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24906565

RESUMEN

PURPOSE: The aim of this study was to analyze the safety, treatment characteristics and survival outcomes of Yttrium-90 (Y90) radioembolization for unresectable colorectal carcinoma (CRC) liver metastases refractory to standard of care therapy. METHODS: A total of 214 patients with CRC metastases were treated with Y90 radioembolization over 12 years. Toxicity was assessed using National Cancer Institute common terminology criteria. Overall survival was analyzed from date of diagnosis of primary cancer, hepatic metastases and from the first Y90. Uni/multivariate analyses were performed. Substratification by era of chemotherapeutics was performed. RESULTS: Most patients were male (60 %) and <65 years old (61 %). Of them, 98 % had been exposed to chemotherapy. Grade 3 lymphocyte, bilirubin, albumin, ALP and AST toxicities were observed in 39 %, 11 %, 10 %, 8 % and 4 % of patients, respectively. Grade 4 lymphocyte and ALP toxicities were observed in 5 % and 3 % of patients, respectively. Median overall survival was 43.0, 34.6, and 10.6 months from date of diagnosis of primary cancer, hepatic metastases and first Y90, respectively. Survival was significantly longer in patients: (1) who received ≤2 cytotoxic drugs (n = 104) than those who received 3 (n = 110) (15.2 vs. 7.5 months, p = 0.0001); and (2) who received no biologic agents (n = 52) compared with those that did (n = 162) (18.6 vs. 9.4 months, p = 0.0001). Multivariate analyses identified ≤2 cytotoxic agents, no exposure to biologics, ECOG 0, tumor burden <25 %, lack of extrahepatic disease and albumin >3 g/dL as independent predictors of survival. CONCLUSION: In this largest metastatic CRC series published to date, Y90 radioembolization was found to be safe; survival varied by prior therapy. Further studies are required to further refine the role of Y90 in metastatic CRC.


Asunto(s)
Carcinoma/secundario , Quimioradioterapia , Neoplasias Colorrectales/secundario , Neoplasias Hepáticas/terapia , Radiofármacos/uso terapéutico , Radioisótopos de Itrio/uso terapéutico , Anciano , Embolización Terapéutica/efectos adversos , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Radiofármacos/efectos adversos , Análisis de Supervivencia , Radioisótopos de Itrio/efectos adversos
9.
Healthcare (Basel) ; 12(13)2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38998788

RESUMEN

Previous studies have explored use of smart glasses in telemedicine, but no study has investigated its use in teleradiography. The purpose of this study was to implement a six-month pilot program for Western Australian X-ray operators (XROs) to use smart glasses to obtain assisted reality support in their radiography practice from their supervising radiographers, and evaluate its effectiveness in terms of XROs' competence improvement and equipment usability. Pretest-posttest design with evaluation of the XROs' competence (including their X-ray image quality) and smart glasses usability by XROs in two remote centers and their supervising radiographers from two sites before and after the program using four questionnaire sets and X-ray image quality review was employed in this experimental study. Paired t-test was used for comparing mean values of the pre- and post-intervention pairs of 11-point scale questionnaire and image quality review items to determine any XROs' radiography competence improvements. Content analysis was used to analyze open questions about the equipment usability. Our study's findings based on 13 participants (11 XROs and 2 supervising radiographers) and 2053 X-ray images show that the assisted reality support helped to improve the XROs' radiography competence (specifically X-ray image quality), with mean post-intervention competence values of 6.16-7.39 (out of 10) and statistical significances (p < 0.001-0.05), and the equipment was considered effective for this purpose but not easy to use.

10.
BMC Zool ; 9(1): 13, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38926870

RESUMEN

BACKGROUND: Many animals appear to preferentially renest in proximity to a site they previously occupied. Evidence of nest fidelity is often inferred from a right skewed distribution of distances between the nests of individuals that breed in two consecutive reproduction episodes, where many individuals nest some arbitrarily close distance to their prior nest and others, in the extended right tail of the distribution, nest far from the nest they previously occupied. Because right skewed distributions of inter-nest distances can arise even when individuals choose nest locations randomly, however, such inferences are prone to error. The importance of null models-used to generate patterns of individual inter-nest distances by processes that do not involve site attachment-for inferences about site fidelity has been known for decades but is still often unappreciated or ignored. METHODS: The right skewed distributions of inter-nest distances observed in two earlier studies of male smallmouth bass (Micropterus dolomieu) suggest prima facie that males exhibit nest site fidelity between annual reproduction episodes, but patterns of inter-nest distances have yet to be compared to an adequate null model. Here, we evaluate the nest site fidelity of marked male M. dolomieu in a decade-long dataset, where we apply a randomization procedure based on the rencontre probability problem to generate null models. Eight observed distributions of individual, annual inter-nest distances are compared to a year-specific null model to determine whether random processes are sufficient to explain the observed distributions of inter-nest distances. RESULTS: Through contrasts between observed annual inter-nest distances and results derived from null models that imposed realistic constraints on behavior, we show that some males were undoubtedly nest-site faithful. To reinforce the utility of null models and to make these kinds of models more accessible, we also provide a supplemental tutorial. The tutorial illustrates how random site choices, subject to common ecological and behavioral constraints, and even how distance is measured, can produce patterns of inter-nest distances that falsely imply nest site fidelity, or a lack of fidelity. The R code needed to reproduce these null models is included. The inference errors evident in our examples generalize to other forms of site fidelity, such as the apparent patch fidelity of certain sea bird foragers. CONCLUSIONS: The comparisons of observed distributions of inter-nest distances with those generated by null models imply that, as suggested in prior studies, male M. dolomieu indeed exhibit annual nest site fidelity. Procedures like those we apply are necessary first steps in analyses when distributions of distances between the nests of individuals in consecutive reproduction episodes are used to infer nest-site fidelity. Why male M. dolomieu are site faithful is a question yet to be answered.

11.
Cell Rep Med ; 5(3): 101437, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38428428

RESUMEN

Leber hereditary optic neuropathy (LHON) is a mitochondrial disease leading to rapid and severe bilateral vision loss. Idebenone has been shown to be effective in stabilizing and restoring vision in patients treated within 1 year of onset of vision loss. The open-label, international, multicenter, natural history-controlled LEROS study (ClinicalTrials.gov NCT02774005) assesses the efficacy and safety of idebenone treatment (900 mg/day) in patients with LHON up to 5 years after symptom onset (N = 199) and over a treatment period of 24 months, compared to an external natural history control cohort (N = 372), matched by time since symptom onset. LEROS meets its primary endpoint and confirms the long-term efficacy of idebenone in the subacute/dynamic and chronic phases; the treatment effect varies depending on disease phase and the causative mtDNA mutation. The findings of the LEROS study will help guide the clinical management of patients with LHON.


Asunto(s)
Atrofia Óptica Hereditaria de Leber , Ubiquinona/análogos & derivados , Humanos , Atrofia Óptica Hereditaria de Leber/tratamiento farmacológico , Atrofia Óptica Hereditaria de Leber/genética , Atrofia Óptica Hereditaria de Leber/diagnóstico , Antioxidantes/uso terapéutico , Ubiquinona/uso terapéutico , Ubiquinona/genética , Mutación
12.
Epilepsia ; 54(8): 1376-80, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23663063

RESUMEN

PURPOSE: Gamma knife radiosurgery (RS) may be an alternative to open surgery for mesial temporal lobe epilepsy (MTLE), but morbidities and the anticonvulsant mechanisms of RS are unclear. Examination of visual field defects (VFDs) after RS may provide evidence of the extent of a postoperative fixed lesion. VFDs occur in 52-100% of patients following open surgery for MTLE. METHODS: This multicenter prospective trial of RS enrolled patients with unilateral hippocampal sclerosis and concordant video-electroencephalography (EEG) findings. Patients were randomized to low (20 Gy) or high (24 Gy) doses delivered to the amygdala, hippocampal head, and parahippocampal gyrus. Postoperative perimetry were obtained at 24 months after RS. Visual field defect ratios (VFDRs) were calculated to quantify the degree of VFDs. Results were contrasted with age, RS dose and 50% isodose volume, peak volume of radiation-induced change at the surgical target, quality of life measurements, and seizure remission. KEY FINDINGS: No patients reported visual changes and no patients had abnormal bedside visual field examinations. Fifteen (62.5%) of 24 patients had postoperative VFDs, all homonymous superior quadrantanopsias. None of the VFDs were consistent with injury to the optic nerve or chiasm. Clinical diagnosis of VFDs correlated significantly with VFDRs (p = 0.0005). Patients with seizure remission had smaller (more severe) VFDRs (p = 0.04). No other variables had significant correlations. SIGNIFICANCE: VFDs appeared after RS in proportions similar to historical comparisons from open surgery for MTLE. The nature of VFDs was consistent with lesions of the optic radiations. The findings support the hypothesis that the mechanism of RS involves some degree of tissue damage and is not confined entirely to functional changes in neuromodulation.


Asunto(s)
Trastornos de la Percepción/etiología , Complicaciones Posoperatorias/etiología , Radiocirugia/efectos adversos , Campos Visuales/fisiología , Relación Dosis-Respuesta en la Radiación , Electroencefalografía , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/cirugía , Estudios de Seguimiento , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Esclerosis/complicaciones , Esclerosis/patología , Estadísticas no Paramétricas , Grabación en Video , Pruebas del Campo Visual
13.
Gastroenterology ; 140(2): 497-507.e2, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21044630

RESUMEN

BACKGROUND & AIMS: Chemoembolization is one of several standards of care treatment for hepatocellular carcinoma (HCC). Radioembolization with Yttrium-90 microspheres is a novel, transarterial approach to radiation therapy. We performed a comparative effectiveness analysis of these therapies in patients with HCC. METHODS: We collected data from 463 patients who were treated with transarterial locoregional therapies (chemoembolization or radioembolization) over a 9-year period. We excluded patients who were not appropriate for comparison and analyzed data from 245 (122 who received chemoembolization and 123 who received radioembolization). Patients were followed for signs of toxicity; all underwent imaging analysis at baseline and follow-up time points. Overall survival was the primary outcome measure. Secondary outcomes included safety, response rate, and time-to-progression. Uni- and multivariate analyses were performed. RESULTS: Abdominal pain and increased transaminase activity were more frequent following chemoembolization (P < .05). There was a trend that patients treated with radioembolization had a higher response rate than with chemoembolization (49% vs 36%, respectively, P = .104). Although time-to-progression was longer following radioembolization than chemoembolization (13.3 months vs 8.4 months, respectively, P = .046), median survival times were not statistically different (20.5 months vs 17.4 months, respectively, P = .232). Among patients with intermediate-stage disease, survival was similar between groups that received chemoembolization (17.5 months) and radioembolization (17.2 months, P = .42). CONCLUSIONS: Patients with HCC treated by chemoembolization or radioembolization with Yttrium-90 microspheres had similar survival times. Radioembolization resulted in longer time-to-progression and less toxicity than chemoembolization. Post hoc analyses of sample size indicated that a randomized study with > 1000 patients would be required to establish equivalence of survival times between patients treated with these two therapies.


Asunto(s)
Carcinoma Hepatocelular/terapia , Embolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Microesferas , Radiofármacos/uso terapéutico , Radioisótopos de Itrio/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Quimioembolización Terapéutica/efectos adversos , Ensayos Clínicos Fase II como Asunto , Progresión de la Enfermedad , Embolización Terapéutica/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Ensayos Clínicos Controlados Aleatorios como Asunto , Nivel de Atención , Resultado del Tratamiento
14.
J Neurooncol ; 110(2): 237-43, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22875709

RESUMEN

To evaluate the toxicity and maximum tolerated dose (MTD) of arsenic trioxide (ATO) in combination with temozolomide (TMZ) and radiation therapy (RT) in malignant gliomas. A 3 + 3 dose escalation study was performed in patients with newly diagnosed glioblastoma, anaplastic astrocytoma (AA), and anaplastic oligoastrocytoma (AOA). All patients received RT 59-61 Gy in 28-33 fractions, TMZ for 42 days, and ATO 1-2 h prior to RT for 5 days during the first week, then twice weekly until completing RT. Dose levels (DL) were: (1) TMZ 60 mg/m(2)/ATO 0.2 mg/kg; (2) TMZ 75 mg/m(2)/ATO 0.2 mg/kg; (3) TMZ 75 mg/m(2)/ATO 0.25 mg/kg. Dose-limiting toxicity (DLT) was defined as grade 3 non-hematologic toxicity or grade 4 toxicity of any type from enrollment until 3 weeks after finishing RT. 17 patients (13 glioblastoma, 4 AA/AOA) were accrued. Median age was 52 (range 25-80). Median KPS was 90 %. DLT's occurred at DL 2 (grade 4 transaminase elevation) and DL 3 (grade 4 neutropenia and grade 3 QTc prolongation). The MTD of TMZ 75 mg/m(2)/ATO 0.2 mg/kg was safe and well tolerated. A phase II study evaluating the efficacy of this combination is underway.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/terapia , Quimioradioterapia , Glioma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Trióxido de Arsénico , Arsenicales/administración & dosificación , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Dacarbazina/administración & dosificación , Dacarbazina/análogos & derivados , Fraccionamiento de la Dosis de Radiación , Femenino , Glioma/mortalidad , Glioma/patología , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Óxidos/administración & dosificación , Pronóstico , Dosificación Radioterapéutica , Tasa de Supervivencia , Temozolomida
15.
Gastroenterology ; 138(1): 52-64, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19766639

RESUMEN

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) has limited treatment options; long-term outcomes following intra-arterial radiation are unknown. We assessed clinical outcomes of patients treated with intra-arterial yttrium-90 microspheres (Y90). METHODS: Patients with HCC (n = 291) were treated with Y90 as part of a single-center, prospective, longitudinal cohort study. Toxicities were recorded using the Common Terminology Criteria version 3.0. Response rate and time to progression (TTP) were determined using World Health Organization (WHO) and European Association for the Study of the Liver (EASL) guidelines. Survival by stage was assessed. Univariate/multivariate analyses were performed. RESULTS: A total of 526 treatments were administered (mean, 1.8; range, 1-5). Toxicities included fatigue (57%), pain (23%), and nausea/vomiting (20%); 19% exhibited grade 3/4 bilirubin toxicity. The 30-day mortality rate was 3%. Response rates were 42% and 57% based on WHO and EASL criteria, respectively. The overall TTP was 7.9 months (95% confidence interval, 6-10.3). Survival times differed between patients with Child-Pugh A and B disease (A, 17.2 months; B, 7.7 months; P = .002). Patients with Child-Pugh B disease who had portal vein thrombosis (PVT) survived 5.6 months (95% confidence interval, 4.5-6.7). Baseline age; sex; performance status; presence of portal hypertension; tumor distribution; levels of bilirubin, albumin, and alpha-fetoprotein; and WHO/EASL response rate predicted survival. CONCLUSIONS: Patients with Child-Pugh A disease, with or without PVT, benefited most from treatment. Patients with Child-Pugh B disease who had PVT had poor outcomes. TTP and overall survival varied by patient stage at baseline. These data can be used to design future Y90 trials and to describe Y90 as a potential treatment option for patients with HCC.


Asunto(s)
Carcinoma Hepatocelular/radioterapia , Embolización Terapéutica/métodos , Neoplasias Hepáticas/radioterapia , Radioisótopos de Itrio/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/mortalidad , Embolización Terapéutica/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Masculino , Microesferas , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Resultado del Tratamiento
16.
J Neurol Surg B Skull Base ; 82(1): 7-19, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33777616

RESUMEN

This article traces the development of orbital surgery and its subsequent modifications. It also points out the importance of defining one's goal before embarking on orbital surgery. Although generally considered part of ophthalmology, surgery on the orbit has been relatively neglected and not routinely practiced. This article reviews the history of development of orbital surgery, both the revolutionary ideas and the evolutionary changes. There are multiple orbital lesions that do not need to be treated with surgery at all. These days chemotherapy, radation therapy, or even immunotherapy may be more appropriate. The most common orbital pathology, that is thyroid orbitopathy, the physician needs to decide whether or not the orbit needs to be decompressed or whether there are problems related to motility that can be dealt with by eye muscle surgery.

17.
Curr Dev Nutr ; 5(2): nzaa180, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33644632

RESUMEN

BACKGROUND: Microgreens are the young leafy greens of many vegetables, herbs, grains, and flowers with potential to promote human health and sustainably diversify the global food system. For successful further integration into the global food system and evaluation of their health impacts, it is critical to elucidate and optimize their nutritional quality. OBJECTIVES: We aimed to comprehensively evaluate the metabolite and mineral contents of 6 microgreen species, and the influence of maturity on their contents. METHODS: Plant species evaluated were from the Brassicaceae (arugula, broccoli, and red cabbage), Amaranthaceae (red beet and red amaranth), and Fabaceae (pea) plant families. Nontargeted metabolomics and ionomics analyses were performed to examine the metabolites and minerals, respectively, in each microgreen species and its mature counterpart. RESULTS: Nontargeted metabolomics analysis detected 3321 compounds, 1263 of which were annotated and included nutrients and bioactive compounds. Ionomics analysis detected and quantified 26 minerals including macrominerals, trace minerals, ultratrace minerals, and other metals. Principal component analysis indicated that microgreens have distinct metabolite and mineral profiles compared with one another and with their mature counterparts. Several compounds were higher (P  < 0.05; fold change ≥2) in microgreens compared with their mature counterparts, whereas some were not different or lower. In many cases, compounds that were higher in microgreens compared with the mature counterpart were also unique to that microgreen species. CONCLUSIONS: These data provide evidence for the nutritional quality of microgreens, and can inform future research and development aimed at characterizing and optimizing microgreen nutritional quality and health impacts.

18.
Radiology ; 255(3): 955-65, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20501733

RESUMEN

PURPOSE: To determine comprehensive imaging and long-term survival outcome following chemoembolization for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: One hundred seventy-two patients with HCC treated with chemoembolization were studied retrospectively in an institutional review board approved protocol; this study was HIPAA compliant. Baseline laboratory and imaging characteristics were obtained. Clinical and laboratory toxicities following treatment were assessed. Imaging characteristics following chemoembolization were evaluated to determine response rates (size and necrosis) and time to progression (TTP). Survival from the time of first chemoembolization treatment was calculated. Subanalyses were performed by stratifying the population according to Child-Pugh, United Network for Organ Sharing, and Barcelona Clinic for Liver Cancer (BCLC) staging systems. RESULTS: Cirrhosis was present in 157 patients (91%); portal hypertension was present in 139 patients (81%). Eleven patients (6%) had metastases at baseline. Portal vein thrombosis was present in 11 patients (6%). Fifty-five percent of patients experienced some form of toxicity following treatment; 21% developed grade 3 or 4 bilirubin toxicity. Post-chemoembolization response was seen in 31% and 64% of patients according to size and necrosis criteria, respectively. Median TTP was 7.9 months (95% confidence interval: 7.1, 9.4) but varied widely by stage. Median survival was significantly different between patients with BCLC stages A, B, and C disease (stage A, 40.0 months; B, 17.4 months; C, 6.3 months; P < .0001). CONCLUSION: The determination of TTP and survival in patients with HCC is confounded by tumor biology and background cirrhosis; chemoembolization was shown to be a safe and effective therapy in patients with HCC.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Imagen por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/complicaciones , Medios de Contraste , Progresión de la Enfermedad , Femenino , Humanos , Hipertensión Portal/complicaciones , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Análisis de Regresión , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
19.
J Vasc Interv Radiol ; 21(1): 90-5, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19939705

RESUMEN

PURPOSE: To identify key prognostic clinical and imaging variables in patients undergoing yttrium-90 radioembolization ((90)Y) for liver malignancies. MATERIALS AND METHODS: Patients with liver malignancies that progressed despite standard-of-care therapy were treated with (90)Y from 2002 to 2006. Baseline functional status, laboratory values, and diagnostic imaging were assessed before therapy. Imaging follow-up was performed 1 month after treatment and subsequently at 3-month intervals. Patients were followed for survival from the time of their first (90)Y treatment. RESULTS: Patients with follow-up imaging after radioembolization (N = 130) were included in this analysis. Primary malignancies included colon, neuroendocrine, and others. The following clinical variables had a significant effect on survival on multivariate analysis: Eastern Cooperative Oncology Group (ECOG) performance status (PS) greater than 0 (hazard ratio [HR], 7.98; 95% CI, 3.98-16), hepatic tumor burden of 51%-75% (HR, 2.46; 95% CI, 1.01-6.02), bilirubin level greater than 1.3 mg/dL (HR, 2.60; 95% CI, 1.27-5.34), hepatic metastases from breast cancer (HR, 2.51; 95% CI, 1.13-5.61), response on imaging based on World Health Organization (WHO) criteria (HR, 0.48; 95% CI, 0.24-0.94), and lymphocyte depression (HR, 0.56; 95% CI, 0.31-0.96). Among patients with colorectal cancer metastases to the liver, the HR for survival on univariate analysis for responders compared with nonresponders (per WHO criteria) was 0.26 (95% CI, 0.10-0.69). CONCLUSIONS: Cancer-related symptoms (ie, ECOG PS > 0), hepatic tumor burden greater than 50%, increased bilirubin levels, and hepatic metastases from breast cancer were found to be negative prognostic factors. Tumor response to therapy and lymphocyte depression were associated with favorable prognosis. Additionally, WHO response was identified to be a favorable prognostic factor in patients with colorectal cancer metastases. These findings may be useful when counseling patients regarding prognosis of their hepatic disease.


Asunto(s)
Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/radioterapia , Radioisótopos de Itrio/uso terapéutico , Anciano , Embolización Terapéutica/estadística & datos numéricos , Femenino , Humanos , Illinois/epidemiología , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Radiografía , Radiofármacos/uso terapéutico , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Tasa de Supervivencia , Resultado del Tratamiento
20.
Retina ; 30(4): 578-85, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19996826

RESUMEN

PURPOSE: The purpose of this study was to report differentiating optical coherence tomography (OCT) findings between postacute retinal arterial occlusion (PARAO) and nonacute optic neuropathy (NAON). METHODS: A retrospective observational comparative study included 17 eyes with postacute permanent retinal arterial occlusion and 32 eyes with NAON whose assessment included a fast macular Status OCT. The macular OCT changes in the postacute phase of central retinal arterial occlusion and branch retinal arterial occlusion were, respectively, compared with those in diffuse and segmental NAON in an effort to establish differentiating features. The findings were used in the workup of four additional consecutive cases referred with suspected NAON. RESULTS: Three main features differentiating PARAO from NAON were identified on macular OCT. Complete inner retinal atrophy with loss of the normal stratification of the inner retinal layers, loss of the normal foveal depression, and marked thinning of the involved retina were characteristic findings of PARAO and were absent even in the most severe cases of NAON. The involved retina was significantly thinner in PARAO compared with that in NAON (P < 0.05). These OCT features helped establish the diagnosis of PARAO in four additional consecutive cases referred with the misdiagnosis of NAON. CONCLUSION: The extent and pattern of inner retinal atrophy differentiate PARAO from NAON and help guide the systemic workup.


Asunto(s)
Enfermedades del Nervio Óptico/patología , Retina/patología , Oclusión de la Arteria Retiniana/patología , Tomografía de Coherencia Óptica/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Presión Intraocular , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Agudeza Visual
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