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1.
Bioscience ; 66(10): 890-896, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29599534

RESUMEN

Biodiversity conservation and agricultural production are often seen as mutually exclusive objectives. Strategies for reconciling them are intensely debated. We argue that harmonization between biodiversity conservation and crop production can be improved by increasing our understanding of the underlying relationships between them. We provide a general conceptual framework that links biodiversity and agricultural production through the separate relationships between land use and biodiversity and between land use and production. Hypothesized relationships are derived by synthesizing existing empirical and theoretical ecological knowledge. The framework suggests nonlinear relationships caused by the multifaceted impacts of land use (composition, configuration, and intensity). We propose solutions for overcoming the apparently dichotomous aims of maximizing either biodiversity conservation or agricultural production and suggest new hypotheses that emerge from our proposed framework.

2.
Biol Lett ; 11(8)2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26246332

RESUMEN

A recent study by Stohlgren & Rejmánek (SR: Stohlgren TJ, Rejmánek M. 2014 Biol. Lett. 10. (doi:10.1098/rsbl.2013.0939)) purported to test the generality of a recent finding of scale-dependent effects of invasive plants on native diversity; dominant invasive plants decreased the intercept and increased the slope of the species-area relationship. SR (2014) find little correlation between invasive species cover and the slopes and intercepts of SARs across a diversity of sites. We show that the analyses of SR (2014) are inappropriate because of confounding causality.


Asunto(s)
Biodiversidad , Extinción Biológica , Helechos/fisiología , Especies Introducidas , Lonicera/fisiología , Myricaceae/fisiología , Plantas/clasificación
3.
Langmuir ; 30(41): 12287-96, 2014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-25254486

RESUMEN

Carboxyl-terminated carbon black (CB) particles have been proposed as readily available, biocompatible dispersants to stabilize oil-in-water emulsions after an oil spill. Since the reduction in interfacial tension and the increase in interfacial elasticity are the key parameters which relate interfacial mechanics to emulsion stability, this investigation explores the effect of CB adsorption and surface coverage on oil-water interfacial tension and elasticity. Flocculation of CB was explored as ionic strength was increased from 0 to 0.6 M, approximately the salinity of seawater. As salinity increases, CB aggregates into larger particles from 100 nm to 6 µm. The interfacial tension and dilational viscoelasticity were measured for two systems: a drop of a CB suspension in oil and an inverted oil drop in a CB suspension. For the arrangement of a CB suspension drop in oil, most of the CB settles and accumulates toward the bottom of the drop with only small surface adsorption and no appreciable effect is observed on the dynamic interfacial tension or the dilational viscoelasticity. On reversing the arrangement to an inverted oil drop in CB suspension and increasing the convection of the outer phase, the surface coverage increases considerably. The CB coverage becomes more uniform with higher convection with an average value of approximately 2.6 g/m(2), which is representative of the coverage in Pickering emulsions stabilized by CB particles. The CB coverage decreases the surface tension from about 30 to 8.5 mN/m accompanied by an increase in the surface elasticity to 20.7 mN/m. The sharp contrast between the results from the CB suspension drop and the oil drop could be partially due to the effect of the wetting characteristics of the particles or due to the significant differences between the convection in the two cases.

4.
AJOG Glob Rep ; 2(4): 100118, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36247708

RESUMEN

BACKGROUND: Severe COVID-19 infection in pregnancy has been associated with an increase in adverse perinatal outcomes, although studies differ regarding which outcomes are affected. Increased characterization of obstetrical and neonatal outcomes is needed, including details on indications for preterm delivery and additional neonatal adverse outcomes. OBJECTIVE: This study aimed to determine whether there is a higher rate of adverse perinatal outcomes with severe-to-critical COVID-19 infection compared with nonsevere COVID-19 diagnosed during pregnancy. STUDY DESIGN: This was a retrospective observational cohort study that compared rates of adverse perinatal outcomes between patients with severe-to-critical and those with nonsevere (asymptomatic, mild, or moderate) COVID-19 infection. Patients had singleton pregnancies and a positive laboratory polymerase chain reaction result for COVID-19. Primary outcomes included hypertensive disorders of pregnancy, cesarean delivery, fetal growth restriction, preterm birth, and neonatal intensive care unit admission. Additional neonatal outcomes analyzed included need for cardiopulmonary resuscitation, low birthweight (<2500 g), 1- or 5-minute Apgar score <7, need for supplemental oxygen, need for intubation, intraventricular hemorrhage, sepsis, respiratory distress syndrome, bronchopulmonary dysplasia, blood transfusion, necrotizing enterocolitis, hypoxic-ischemic encephalopathy, birth trauma, or neonatal death. Appropriate bivariate analyses were used to compare groups. Logistic regression was used to examine primary outcomes while adjusting for confounders. RESULTS: A total of 441 participants were identified and confirmed via detailed chart review to be pregnant with a singleton pregnancy while diagnosed with COVID-19. Of these, 44 (10%) met National Institutes of Health criteria for severe-to-critical COVID-19 infection. The median gestational age at the time of maternal COVID-19 diagnosis was 36.4 weeks (interquartile range, 29.6-38.6). Severe-to-critical COVID-19 infection had a higher risk of a composite adverse neonatal outcome (36.4% vs 21.4%; P=.03). There was a high incidence of hypertensive disorders of pregnancy overall (20.6%), but this outcome was not higher in the severe-to-critical vs nonsevere group. There were no maternal deaths. There was a low incidence of neonatal COVID-19 test positivity among those tested (1.8%). When adjusting for presence of heart disease and gestational age at COVID-19 diagnosis, severe-to-critical COVID-19 was strongly associated with fetal growth restriction (adjusted odds ratio, 2.73; confidence interval, 1.03-7.25) and neonatal intensive care unit admission (adjusted odds ratio, 3.50; confidence interval, 1.56-7.87). Preterm delivery was more common but was no longer significant after adjustment (adjusted odds ratio, 2.23; confidence interval, 0.99-5.05). CONCLUSION: Severe-to-critical COVID-19 infection during pregnancy is associated with higher rates of adverse neonatal outcomes and strongly associated with neonatal intensive care unit admission and fetal growth restriction compared with nonsevere disease. There is a high rate of hypertensive disorders of pregnancy overall in all those affected by COVID-19, regardless of severity. Pregnant persons should be counseled on these risks to encourage vaccination, and those with infection during pregnancy should be monitored for fetal growth disorders.

5.
Am J Bot ; 98(3): 539-48, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21613145

RESUMEN

PREMISE OF THE STUDY: Invasive plant species are typically thought to pose a large threat to native biodiversity, and local-scale studies typically confirm this view. However, plant invaders rarely cause regional extirpations or global extinctions, causing some to suggest that invasive species' influence on native biodiversity may not be so dire. We aim to synthesize the seemingly conflicting literature in plant invasion biology by evaluating the effects of invasive plant species across spatial scales. METHODS: We first conducted a meta-analysis on the effects of invasive plants on the species richness of invaded communities across a range of spatial extents. We then discuss studies that consider the role of invasive plants on regional spatial scales for which such meta-analyses are not possible. Finally, we develop a conceptual framework to synthesize the influence of invasive species across spatial scales by explicitly recognizing how invasive species alter species-occupancy distributions. KEY RESULTS: We found a negative relationship between the spatial extent of the study and the effect size of invasive plants on species richness. Our simulation models suggest that this result can occur if invaders, either proportionately or disproportionately, reduce the occupancy of common species to a greater degree than rare species. CONCLUSIONS: Future studies should consider the influence of invaders on the abundance and occupancy-level changes in native species to inform how invasive plants will influence native species richness relationships across spatial scales. This approach will allow greater predictive ability for forecasting changes in biodiversity in the face of anthropogenic biological invasions and will inform invasive species management and restoration.


Asunto(s)
Biodiversidad , Especies Introducidas , Modelos Biológicos
6.
Womens Health Issues ; 29 Suppl 1: S103-S111, 2019 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-31253233

RESUMEN

BACKGROUND: Although most suicide-related deaths occur among male veterans, women veterans are dying by suicide in increasing numbers. Identifying and increasing access to effective treatments is imperative for Department of Veterans Affairs suicide prevention efforts. We examined the impact of evidence-based psychotherapies for depression on suicidal ideation and the role of gender and treatment type in patients' responses to treatment. METHODS: Clinicians receiving case consultation in interpersonal psychotherapy, cognitive-behavioral therapy for depression, and acceptance and commitment therapy for depression submitted data on depressive symptoms and suicidal ideation while treating veterans with depression. RESULTS: Suicidal ideation was reduced across time in all three treatments. A main effect for wave was associated with statistically significant decreases in severity of suicidal ideation, χ2 (2) = 224.01, p = .0001, and a subsequent test of the Gender × Wave interaction was associated with differentially larger decreases in ideation among women veterans, χ2 (2) = 9.26, p = .001. Within gender-stratified subsamples, a statistically significant Treatment × Time interaction was found for male veterans, χ2 (4) = 16.82, p = .002, with levels of ideation significantly decreased at waves 2 and 3 in interpersonal psychotherapy and cognitive-behavioral therapy for depression relative to acceptance and commitment therapy for depression; the Treatment × Wave interaction within the female subsample was not statistically significant, χ2 (4) = 3.41, p = .492. CONCLUSIONS: This analysis demonstrates the efficacy of each of the three tested evidence-based psychotherapies for depression as a means of decreasing suicidal ideation, especially in women veterans. For male veterans, decreases in suicidal ideation were significantly greater in interpersonal psychotherapy and cognitive-behavioral therapy for depression relative to acceptance and commitment therapy for depression.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Depresión/terapia , Práctica Clínica Basada en la Evidencia , Ideación Suicida , Prevención del Suicidio , Veteranos/psicología , Adulto , Depresión/psicología , Trastorno Depresivo/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicoterapia , Resultado del Tratamiento
7.
Int J Pharm ; 549(1-2): 466-475, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30099213

RESUMEN

Cystinosis is a genetic disorder that leads to the formation of cystine crystals in many organs in the body including cornea. Ocular manifestation of this disease is treated by eye drops of cysteamine which can easily oxidize into its disulfide cystamine. The rapid oxidation limits the shelf life as well the duration during which the drug can be used after opening the eye drop bottle. We evaluate two approaches of preventing the oxidation of cysteamine with the goal of increasing the time of use after opening the bottle to one month. The first approach integrates antioxidants such as catalase enzyme and vitamins C and E into the aqueous solution. Results show that catalase is the most effective additive as it decreases the oxidation rate by 58%, which on its own is not sufficient to reach targeted one month stability. The second approach focuses on incorporating diffusion barriers to prevent oxygen from reaching the cysteamine solution. This was accomplished by two methods: formulation of a hydrophobic layer which floats on the surface of the aqueous solution and integration of OMAC® oxygen-resistant material into the eye drop bottle. Both methods delay the onset of cysteamine degradation and decrease the rate of degradation. In particular, an eye drop bottle with three layers of OMAC® has less than 10% degradation after one month of opening the bottle and withdrawing a drop each day. By integrating all three methods, we designed a system where >90% of cysteamine remains in the active form for 70 days after opening the bottle. In addition, we examine the use of OMAC® as heat-sealed pouches for storage of cysteamine eye drop bottles during packaging to eliminate the need for the current approach of freezing the formulation during shipping. The results show that such heat-sealed pouches would keep cysteamine stable for over one year at ambient conditions.


Asunto(s)
Antioxidantes/química , Catalasa/química , Cisteamina/química , Depletores de Cistina/química , Embalaje de Medicamentos , Oxígeno/química , Aceite de Soja/química , Administración Oftálmica , Ácido Ascórbico/química , Cisteamina/administración & dosificación , Depletores de Cistina/administración & dosificación , Composición de Medicamentos , Estabilidad de Medicamentos , Interacciones Hidrofóbicas e Hidrofílicas , Soluciones Oftálmicas , Oxidación-Reducción , Tecnología Farmacéutica/métodos , Factores de Tiempo , Vitamina E/química
8.
Case Rep Obstet Gynecol ; 2017: 3701450, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28127487

RESUMEN

Background. Uterine fibroids are common benign tumors in women. Clinical manifestations are well known. Acute complications necessitating emergent surgical intervention are rare. Case. We report a case of a 53-year-old woman with a history of uterine fibroids presenting with acute-onset severe abdominal pain. Imaging indicated massive free fluid and a large partially solid uterine mass. Vitals were consistent with hypovolemic shock. Examination revealed a surgical abdomen. She underwent an emergent laparotomy and total hysterectomy. Surgery revealed 4.5 L of hemoperitoneum and a 15 cm degenerated uterine fibroid with active bleeding. Pathology was consistent with intraoperative findings. She required transfusion of numerous blood products perioperatively. Her postoperative course was uncomplicated. Conclusion. It is rare for a uterine fibroid to spontaneously rupture. However, prompt recognition of this severe complication is critical for expeditious, life-saving surgical management.

9.
Int J Pharm ; 521(1-2): 8-18, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28192158

RESUMEN

We explore mechanisms of emulsion stability for several systems using Pluronic F68 and a range of oils commonly used in pharmaceutics and cosmetics. We report measurements of dynamic emulsion drop size, zeta potential, and creaming time, as well as dynamic interfacial tension and interfacial viscoelasticity. Experiments show that with 1wt% Pluronic F68, soybean oil emulsions were the most stable with no creaming over six months, followed by isopropyl myristate, octanoic acid, and then ethyl butyrate. The eventual destabilization occurred due to the rising of large drops which formed through Ostwald ripening and coalescence. While Ostwald ripening is important, it is not the dominant destabilization mechanism for the time scale of interest in pharmaceutical emulsions. The more significant destabilization mechanism, coalescence, is reduced through surfactant adsorption, which decreases surface tension, increases surface elasticity, and adds a stearic hindrance to collisions. Though the measured values of elasticity obtained using a standard oscillatory pendant drop method did not correlate to emulsion stability, this is because the frequencies for the measurements were orders of magnitude below those relevant to coalescence in emulsions. However, we show that the high frequency elasticity obtained by fitting the surface tension data to a Langmuir isotherm has very good correlation with the emulsion stability, indicating that the elasticity of the interface plays a key role in stabilizing these pharmaceutical formulations. Further, this study highlights how these important high frequency elasticity values can be easily estimated from surface isotherms.


Asunto(s)
Poloxámero/química , Tensoactivos/química , Estabilidad de Medicamentos , Emulsiones/química , Tensión Superficial
10.
Adv Colloid Interface Sci ; 233: 139-154, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26318359

RESUMEN

Ophthalmic drug for the anterior chamber diseases are delivered into tears by either eye drops or by extended release devices placed in the eyes. The instilled drug exits the eye through various routes including tear drainage into the nose through the canaliculi and transport across various ocular membranes. Understanding the mechanisms relevant to each route can be useful in predicting the dependency of ocular bioavailability on various formulation parameters, such as drug concentration, salinity, viscosity, etc. Mathematical modeling has been developed for each of the routes and validated by comparison with experiments. The individual models can be combined into a system model to predict the fraction of the instilled drug that reaches the target. This review summarizes the individual models for the transport of drugs across the cornea and conjunctiva and the canaliculi tear drainage. It also summarizes the combined tear dynamics model that can predict the ocular bioavailability of drugs instilled as eye drops. The predictions from the individual models and the combined model are in good agreement with experimental data. Both experiments and models predict that the corneal bioavailability for drugs delivered through eye drops is less than 5% due to the small area of the cornea in comparison to the conjunctiva, and the rapid clearance of the instilled solution by tear drainage. A contact lens is a natural choice for delivering drugs to the cornea due to the placement of the contact in the immediate vicinity of the cornea. The drug released by the contact towards the cornea surface is trapped in the post lens tear film for extended duration of at least 30min allowing transport of a large portion into the cornea. The model predictions backed by in vivo animal and clinical data show that the bioavailability increases to about 50% with contact lenses. This realization has encouraged considerable research towards delivering ocular drugs by contact lenses. Commercial contacts are, however, not ideal for drug delivery due to the short release durations which may necessitate wearing multiple lenses each day, reducing the viability of this approach. Recent research has focused on designing contacts that retain all critical properties while increasing the release durations to a few hours or a few days. Beagle dog studies with contact lenses containing vitamin E nanobarriers to attenuate drug transport have shown promising results. Human studies using contacts for drug delivery have also been conducted for allergy therapy but drug eluting contacts are not available in the market for any therapy.


Asunto(s)
Cámara Anterior/efectos de los fármacos , Conjuntiva/efectos de los fármacos , Córnea/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Modelos Estadísticos , Soluciones Oftálmicas/farmacocinética , Administración Oftálmica , Animales , Cámara Anterior/metabolismo , Disponibilidad Biológica , Transporte Biológico , Conjuntiva/metabolismo , Lentes de Contacto , Córnea/metabolismo , Perros , Humanos , Lágrimas/metabolismo , Viscosidad
11.
Expert Opin Ther Pat ; 25(10): 1117-29, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26143943

RESUMEN

INTRODUCTION: Ophthalmic drugs are almost exclusively delivered via eye drops in spite of several deficiencies, including low bioavailability and poor compliance. Contact lenses have the potential to increase bioavailability by an order of magnitude, while also improving compliance. AREAS COVERED: In this review, the authors summarize advances in therapeutic contact lenses. The major focus of the review is on patents on drug-eluting contact lenses, but non-drug-eluting contacts that offer a therapeutic benefit are also included. The content is divided based on the broad technology of the patent, including novel materials, molecular imprinting, diffusion barriers, colloid encapsulation, surface modification, layering, and other novel approaches. In addition to patents, research publications are also included to facilitate the understanding of the mechanisms and challenges. EXPERT OPINION: Among all non-invasive alternatives, contact lenses offer the highest bioavailability to the cornea due to the location of the lens in the immediate vicinity of the cornea. Several approaches have been patented to improve contact lens design for an extended release duration of drugs. Many technologies have successfully integrated suitable drug release profiles into contact lenses, but drug-eluting contacts are not yet commercialized likely due to regulatory challenges, including the high costs of clinical trials.


Asunto(s)
Lentes de Contacto , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Administración Oftálmica , Animales , Disponibilidad Biológica , Córnea/metabolismo , Humanos , Cumplimiento de la Medicación , Patentes como Asunto
12.
J Clin Psychiatry ; 64(2): 182-91, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12633127

RESUMEN

BACKGROUND: Several studies have established the efficacy of psychosocial interventions as adjuncts to pharmacotherapy in the symptom maintenance of bipolar disorder. This study concerned a new psychosocial approach - integrated family and individual therapy (IFIT) - that synthesizes family psychoeducational sessions with individual sessions of interpersonal and social rhythm therapy. METHOD: Shortly after an acute illness episode, 30 bipolar patients (DSM-IV criteria) were assigned to open treatment with IFIT (up to 50 weekly sessions of family and individual therapy) and mood-stabilizing medications in the context of a treatment development study. Their outcomes over 1 year were compared with the outcomes of 70 patients from a previous trial who received standard community care, consisting of 2 family educational sessions, mood-stabilizing medications, and crisis management (CM). Patients in both samples were evaluated as to symptomatic functioning at entry into the project and then every 3 months for 1 year. RESULTS: Patients in IFIT had longer survival intervals (time without relapsing) than patients in CM. They also showed greater reductions in depressive symptoms over 1 year of treatment relative to their baseline levels. The results could not be explained by group differences in baseline symptoms or pharmacologic treatment regimens. CONCLUSION: Combining family and individual therapy with medication may protect episodic bipolar patients from early relapse and ongoing depressive symptoms. Further examination of this integrative model within randomized controlled trials is warranted.


Asunto(s)
Trastorno Bipolar/terapia , Terapia Familiar/métodos , Psicoterapia/métodos , Adulto , Anticonvulsivantes/uso terapéutico , Antipsicóticos/uso terapéutico , Trastorno Bipolar/prevención & control , Trastorno Bipolar/psicología , Protocolos Clínicos , Terapia Cognitivo-Conductual/métodos , Terapia Combinada/métodos , Intervención en la Crisis (Psiquiatría)/métodos , Femenino , Estudios de Seguimiento , Hospitalización , Humanos , Litio/uso terapéutico , Masculino , Escalas de Valoración Psiquiátrica , Psicoterapia de Grupo/métodos , Prevención Secundaria , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Resultado del Tratamiento
13.
J Child Neurol ; 19(10): 785-97, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15559894

RESUMEN

"Executive function" is a term describing the processes required for conscious control of thought, emotion, and action that are central to the management of one's day-to-day life. Executive function is subserved by the prefrontal cortex and related subcortical structures. Disorders affecting the prefrontal cortex-subcortical system are numerous and heterogeneous, but contemporary research has begun to elucidate the mechanisms and consequences of dysfunction in various subsystems with increasing specificity. Prefrontal executive dysfunction results in impaired regulation of cognition, attention, behaviors, arousal, and emotion, all of which have serious and pervasive consequences for functioning across the life span. These executive function deficits are typically difficult to treat, ameliorate, or remediate and require sensitive handling by caretakers. Executive dysfunction can arise as a consequence of many different factors (metabolic, genetic, certain types of epilepsy, cerebral dysgenesis, prematurity, traumatic brain injury, hypoxia, and toxic exposure). The present review delineates the features of prefrontal executive function deficits in children and proposes a roadmap for their diagnosis, treatment, and management.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/terapia , Corteza Prefrontal/fisiopatología , Adolescente , Adulto , Niño , Trastornos de la Conducta Infantil/etiología , Trastornos de la Conducta Infantil/psicología , Trastornos de la Conducta Infantil/terapia , Femenino , Humanos , Masculino , Ilustración Médica , Pruebas Neuropsicológicas , Corteza Prefrontal/patología , Síndrome
14.
Science ; 339(6117): 316-8, 2013 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-23329045

RESUMEN

Although invasive plant species often reduce diversity, they rarely cause plant extinctions. We surveyed paired invaded and uninvaded plant communities from three biomes. We reconcile the discrepancy in diversity loss from invaders by showing that invaded communities have lower local richness but steeper species accumulation with area than that of uninvaded communities, leading to proportionately fewer species loss at broader spatial scales. We show that invaders drive scale-dependent biodiversity loss through strong neutral sampling effects on the number of individuals in a community. We also show that nonneutral species extirpations are due to a proportionately larger effect of invaders on common species, suggesting that rare species are buffered against extinction. Our study provides a synthetic perspective on the threat of invasions to biodiversity loss across spatial scales.


Asunto(s)
Extinción Biológica , Helechos/fisiología , Especies Introducidas , Lonicera/fisiología , Myricaceae/fisiología , Biodiversidad , Florida , Hawaii , Missouri , Árboles/fisiología
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