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1.
J Pediatr Hematol Oncol ; 46(5): 252-261, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38787686

RESUMEN

Thrombopoietin receptor agonists (TPO-RAs) induce trilineage hematopoiesis under conditions with acquired hematopoietic failure. We evaluated safety, tolerability, and preliminary efficacy of a TPO-RA, romiplostim (Nplate), with or without standard-of-care immunosuppressive therapy (±IST) for children (ages < 21 y) with newly diagnosed and relapsed/refractory severe aplastic anemia (SAA) and myelodysplastic syndrome (MDS). Data were collected from an observational study and a single arm interventional pilot study. The safety outcome was treatment-related adverse events (AEs). Efficacy was evaluated by complete hematopoietic response (CHR) at week 24. Romiplostim was commenced at 5 µg/kg/week, with dose escalation of 2.5 µg/kg/week (maximum, 20 µg/kg/dose) based on platelet response. Romiplostim was continued until CHR was observed. Ten subjects (SAA, 9 [IST, 4; without IST, 5]; MDS, 1) completed the study (median age: 9.2 y). Median romiplostim dose was 10 µg/kg/week (range: 5 to 17.5 µg/kg/week). The cumulative incidence of CHR was 70.4% (95% CI, 20.2%-92.6%). Among 21 AEs (Grade 1 to 3), 3 were attributed to romiplostim. At a median posttherapy follow-up of 10.9 months (range: 0.7 to 77.5), no clonal evolution, bone marrow fibrosis or mortality was reported. This proof-of-concept study provides data about short-term safety, tolerability, and preliminary efficacy of romiplostim (±IST) for treatment of pediatric SAA/MDS.


Asunto(s)
Anemia Aplásica , Síndromes Mielodisplásicos , Receptores Fc , Proteínas Recombinantes de Fusión , Trombopoyetina , Humanos , Proteínas Recombinantes de Fusión/uso terapéutico , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/efectos adversos , Receptores Fc/uso terapéutico , Receptores Fc/administración & dosificación , Anemia Aplásica/tratamiento farmacológico , Trombopoyetina/uso terapéutico , Trombopoyetina/efectos adversos , Trombopoyetina/administración & dosificación , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/patología , Niño , Femenino , Adolescente , Masculino , Adulto Joven , Preescolar , Proyectos Piloto , Adulto , Receptores de Trombopoyetina/agonistas
2.
Science ; 384(6694): 453-458, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38662833

RESUMEN

Governments recently adopted new global targets to halt and reverse the loss of biodiversity. It is therefore crucial to understand the outcomes of conservation actions. We conducted a global meta-analysis of 186 studies (including 665 trials) that measured biodiversity over time and compared outcomes under conservation action with a suitable counterfactual of no action. We find that in two-thirds of cases, conservation either improved the state of biodiversity or at least slowed declines. Specifically, we find that interventions targeted at species and ecosystems, such as invasive species control, habitat loss reduction and restoration, protected areas, and sustainable management, are highly effective and have large effect sizes. This provides the strongest evidence to date that conservation actions are successful but require transformational scaling up to meet global targets.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Extinción Biológica , Especies Introducidas , Animales , Ecosistema
3.
Pharm Res ; 41(1): 39-50, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37848751

RESUMEN

OBJECTIVE: This study aimed to determine the extent and rate of lidocaine released in vivo from two bioequivalent topical delivery systems (TDS) by using complementary assessments: pharmacokinetic analysis in healthy human volunteers, and residual lidocaine in TDS following 12 h of wear. The goal was to explore a potentially more clinically meaningful strength presentation than percent active pharmaceutical ingredient loaded in topical systems. METHODS: A three-arm, open-label, crossover clinical study was conducted in 23 human subjects, with 5% lidocaine topical systems from two manufacturers, and intravenous lidocaine administration. Residual drug and LC-MS/MS analyses were performed on worn TDS and serum samples. The rate and extent of drug released from the TDS during wear were determined through (1) calculations of consumed lidocaine via analysis of residual drug in worn TDS, and (2) a pharmacokinetic approach via derivation of the absolute clearance and serum lidocaine concentration at steady state. RESULTS: Overall the pharmacokinetic approach underestimated the amount transferred to the subject and exhibited greater variability, which may relate to natural inter-subject variability in pharmacokinetic parameters. Further, lidocaine TDS are intended for localized, not systemic, delivery and this may also explain some of the variability seen in the systemic serum concentrations. CONCLUSIONS: The residual drug and pharmacokinetic approaches align well for transdermal formulations, but the differences in administration route (topical versus transdermal) all but eliminates the potential use of the pharmacokinetic approach unless additional compartmental modeling is explored.


Asunto(s)
Lidocaína , Espectrometría de Masas en Tándem , Humanos , Preparaciones Farmacéuticas , Cromatografía Liquida , Administración Cutánea , Sistemas de Liberación de Medicamentos
4.
Skin Pharmacol Physiol ; 34(4): 214-228, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33910205

RESUMEN

INTRODUCTION: The continuous availability of open micropores is crucial for a successful microneedle (MN) drug delivery strategy. However, micropore lifetime depends on intrinsic skin functional and anatomical characteristics, which vary significantly at different anatomical sites. OBJECTIVE: This pilot study explored if differences exist in micropore closure timeframes at 3 anatomical sites - upper arm, volar forearm, and abdomen. METHODS: Healthy subjects (n = 35) self-identifying as Asian (n = 9), Bi-/multiracial (n = 2), Black (n = 9), Latino (n = 6), and White (n = 9) completed the study. The upper arm, volar forearm, and abdomen were treated with MNs; skin impedance and transepidermal water loss (TEWL) were measured at baseline and post-MN to confirm micropore formation. Impedance was measured for 3 days to evaluate micropore lifetime. Measurements of L*, which quantifies the skin lightness/darkness, were made using a tristimulus colorimeter. Micropore lifetime was determined by comparing baseline and post-MN impedance measurements, and micropore closure half-life was predicted using mathematical modeling. RESULTS: Post-MN increase in TEWL and decrease in impedance were significant (p < 0.05), confirming successful micropore formation at all anatomical sites. When data were analyzed according to subject self-identified racial/ethnic groups, the mean micropore closure time at the abdomen (63.09 ± 13.13 h) was longer than the upper arm (60.34 ± 14.69 h) and volar forearm (58.29 ± 16.76 h). The predicted micropore closure half-life at anatomical sites was the abdomen (25.86 ± 14.96 h) ≈ upper arm (23.69 ± 13.67 h) > volar forearm (20.2 ± 11.99 h). Differences were not statistically significant between groups. Objective categorization by L* showed that the darker skin may be associated with longer micropore closure time at the abdomen site. CONCLUSIONS: Our results suggest that anatomical site of application may not be a source of significant variability in micropore closure time. These findings may help reduce the number of physiological parameters that need to be explicitly considered when developing drug products to support MN-assisted drug delivery strategies.


Asunto(s)
Abdomen/fisiología , Brazo/fisiología , Microinyecciones/métodos , Absorción Cutánea/fisiología , Adolescente , Adulto , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Grupos Raciales , Fenómenos Fisiológicos de la Piel , Adulto Joven
5.
Sci Rep ; 10(1): 18963, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33144596

RESUMEN

Microneedles (MNs) allow transdermal delivery of skin-impermeable drugs by creating transient epidermal micropores, and micropore lifetime directly affects drug diffusion timeframes. Healthy subjects (n = 111) completed the study, self-identifying as Asian (n = 32), Bi-/multi-racial (n = 10), Black (n = 22), White (n = 23), Latino (n = 23), and Native American/Hawaiian (n = 1). L* was measured with tristimulus colorimetry to objectively describe skin lightness/darkness. MNs were applied to the upper arm; impedance and transepidermal water loss (TEWL) were measured at baseline and post-MN to confirm micropore formation. Impedance was repeated for 4 days to determine micropore lifetime. Post-MN changes in TEWL and impedance were significant in all groups (p < 0.05), confirming micropore formation regardless of skin type. Micropore lifetime was significantly longer in Blacks (66.5 ± 19.5 h) versus Asians (44.1 ± 14.0 h), Bi-/multi-racial (48.0 ± 16.0 h), and Whites (50.2 ± 2.6 h). Latinos (61.1 ± 16.1 h) had significantly longer micropore closure time versus Asians (44.1 ± 14.0 h). When categorizing data according to L*, micropore lifetime was significantly longer in darker skin. We report for the first time that micropore lifetime differences are present in human subjects of different ethnic/racial backgrounds, with longer micropore lifetime in skin of color. These results also suggest that objectively measured skin color is a better predictor of micropore lifetime than self-identified race/ethnicity.


Asunto(s)
Microinyecciones/métodos , Pigmentación de la Piel/fisiología , Piel/metabolismo , Administración Cutánea , Colorimetría , Espectroscopía Dieléctrica , Sistemas de Liberación de Medicamentos , Humanos
6.
AAPS PharmSciTech ; 21(3): 117, 2020 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-32300962

RESUMEN

To estimate strength of a scopolamine transdermal delivery system (TDS) in vivo, using residual drug vs. pharmacokinetic analyses with the goal of scientifically supporting a single and robust method for use across the dosage form and ultimately facilitate the development of more consistent and clinically meaningful labeling. A two-arm, open-label, crossover pharmacokinetic study was completed in 26 volunteers. Serum samples were collected and residual scopolamine was extracted from worn TDS. Delivery extent and rate were estimated by (1) numeric deconvolution and (2) steady-state serum concentration determined from graphical and non-compartmental analyses. In residual drug analyses, mean ± SD scopolamine release rate was 0.015 ± 0.002 mg/h (11% RSD), vs. 0.016 ± 0.006 mg/h (35% RSD) from numeric deconvolution, 0.015 ± 0.005 mg/h (34% RSD) from graphical analysis, and 0.015 ± 0.007 mg/h (44% RSD) from non-compartmental analysis. In residual drug analyses, total drug released was 1.09 ± 0.11 mg (10% RSD), vs. 1.12 ± 0.40 mg (35% RSD) from numeric deconvolution, 1.07 ± 0.35 mg (33% RSD) from graphical analysis, and 1.07 ± 0.45 (42% RSD) from non-compartmental analysis. Extent and rate of scopolamine release were comparable by both approaches, but pharmacokinetic analysis demonstrated greater inter-subject variability.


Asunto(s)
Sistemas de Liberación de Medicamentos , Escopolamina/administración & dosificación , Administración Cutánea , Adolescente , Adulto , Estudios Cruzados , Liberación de Fármacos , Femenino , Humanos , Masculino , Escopolamina/química , Escopolamina/farmacocinética , Adulto Joven
7.
J Environ Radioact ; 192: 295-311, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30015315

RESUMEN

Layers of permafrost developed during the 1950s and 1960s incorporated tritium from the atmosphere that originated from global nuclear weapons testing. In regions underlain by substantial permafrost, this tritium has been effectively trapped in ice since it was deposited and subject to radioactive decay alone, which has substantially lengthened its environmental half-life compared to areas with little or no permafrost where the weapons-test era precipitation has been subject to both decay and hydrodynamic dispersion. The Arctic is warming three times faster than other parts of the world, with northern regions incurring some of the most pronounced effects of climate change, resulting in permafrost degradation. A series of 23 waterbodies across the Canadian sub-Arctic spanning the continuous, discontinuous and isolated patches permafrost zones in northern Manitoba, Northwest Territories and Labrador were sampled. Surface water and groundwater seepage samples were collected from each lake and analyzed for tritium, stable isotopes (δ18O and δ2H) and general water chemistry characteristics. Measured tritium was significantly higher in surface waters (SW) and groundwater seepage (GW) in water bodies located in the sporadic discontinuous (64 ±â€¯15 T U. in SW and 52 ±â€¯9 T U. in GW) and extensive discontinuous (53 ±â€¯7 T U. in SW and 61 ±â€¯7 T U. in GW) permafrost regions of the Northwest Territories than in regions underlain by continuous permafrost in northern Manitoba (<12 T U. in both SW and GW) or those within isolated patches of permafrost in Labrador (16 ±â€¯2 T U. in SW and 21 ±â€¯4 T U. in GW). The greatest tritium enrichment (up to 128 T U.) was observed in lakes near Jean Marie River in the Mackenzie River valley, a region known to be experiencing extensive permafrost degradation. These results demonstrate significant permafrost degradation in the central Mackenzie River basin and show that tritium is becoming increasingly mobile in the sub-Arctic environment-at concentrations higher than expected-as a result of a warming climate. A better understanding of the cycling of tritium in the environment will improve our understanding of Arctic radioecology under changing environmental conditions.


Asunto(s)
Agua Subterránea/química , Hielos Perennes/química , Monitoreo de Radiación , Tritio/análisis , Contaminantes Radiactivos del Agua/análisis , Regiones Árticas , Canadá , Cambio Climático , Ecosistema , Lagos
8.
Conserv Biol ; 32(1): 135-147, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28861903

RESUMEN

International Union for Conservation of Nature (IUCN) Red List assessments rely on published data and expert inputs, and biases can be introduced where underlying definitions and concepts are ambiguous. Consideration of climate change threat is no exception, and recently numerous approaches to assessing the threat of climate change to species have been developed. We explored IUCN Red List assessments of amphibians and birds to determine whether species listed as threatened by climate change display distinct patterns in terms of habitat occupied and additional nonclimatic threats faced. We compared IUCN Red List data with a published data set of species' biological and ecological traits believed to infer high vulnerability to climate change and determined whether distributions of climate change-threatened species on the IUCN Red List concur with those of climate change-threatened species identified with the trait-based approach and whether species possessing these traits are more likely to have climate change listed as a threat on the IUCN Red List. Species in some ecosystems (e.g., grassland, shrubland) and subject to particular threats (e.g., invasive species) were more likely to have climate change as a listed threat. Geographical patterns of climate change-threatened amphibians and birds on the IUCN Red List were incongruent with patterns of global species richness and patterns identified using trait-based approaches. Certain traits were linked to increases or decreases in the likelihood of a species being threatened by climate change. Broad temperature tolerance of a species was consistently related to an increased likelihood of climate change threat, indicating counterintuitive relationships in IUCN assessments. To improve the robustness of species assessments of the vulnerability or extinction risk associated with climate change, we suggest IUCN adopt a more cohesive approach whereby specific traits highlighted by our results are considered in Red List assessments. To achieve this and to strengthen the climate change-vulnerability assessments approach, it is necessary to identify and implement logical avenues for further research into traits that make species vulnerable to climate change (including population-level threats).


Asunto(s)
Cambio Climático , Extinción Biológica , Animales , Sesgo , Conservación de los Recursos Naturales , Ecosistema , Especies en Peligro de Extinción
9.
Gigascience ; 6(12): 1-22, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29053868

RESUMEN

Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states.LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600-12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales.


Asunto(s)
Bases de Datos Factuales , Lagos/química , Calidad del Agua , Estados Unidos
10.
Proc Biol Sci ; 284(1862)2017 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-28904135

RESUMEN

Mitigation of anthropogenic climate change involves deployments of renewable energy worldwide, including wind farms, which can pose a significant collision risk to volant animals. Most studies into the collision risk between species and wind turbines, however, have taken place in industrialized countries. Potential effects for many locations and species therefore remain unclear. To redress this gap, we conducted a systematic literature review of recorded collisions between birds and bats and wind turbines within developed countries. We related collision rate to species-level traits and turbine characteristics to quantify the potential vulnerability of 9538 bird and 888 bat species globally. Avian collision rate was affected by migratory strategy, dispersal distance and habitat associations, and bat collision rates were influenced by dispersal distance. For birds and bats, larger turbine capacity (megawatts) increased collision rates; however, deploying a smaller number of large turbines with greater energy output reduced total collision risk per unit energy output, although bat mortality increased again with the largest turbines. Areas with high concentrations of vulnerable species were also identified, including migration corridors. Our results can therefore guide wind farm design and location to reduce the risk of large-scale animal mortality. This is the first quantitative global assessment of the relative collision vulnerability of species groups with wind turbines, providing valuable guidance for minimizing potentially serious negative impacts on biodiversity.


Asunto(s)
Aves , Quirópteros , Mortalidad , Centrales Eléctricas , Energía Renovable , Viento , Distribución Animal , Migración Animal , Animales , Cambio Climático , Ecosistema
11.
Proc Biol Sci ; 282(1818): 20151561, 2015 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-26511054

RESUMEN

Despite increasing concerns about the vulnerability of species' populations to climate change, there has been little overall synthesis of how individual population responses to variation in climate differ between taxa, with trophic level or geographically. To address this, we extracted data from 132 long-term (greater than or equal to 20 years) studies of population responses to temperature and precipitation covering 236 animal and plant species across terrestrial and freshwater habitats. Our results identify likely geographical differences in the effects of climate change on populations and communities in line with macroecological theory. Temperature tended to have a greater overall impact on populations than precipitation, although the effects of increased precipitation varied strongly with latitude, being most positive at low latitudes. Population responses to increased temperature were generally positive, but did not vary significantly with latitude. Studies reporting significant climatic trends through time tended to show more negative effects of temperature and more positive effects of precipitation upon populations than other studies, indicating climate change has already impacted many populations. Most studies of climate change impacts on biodiversity have focused on temperature and are from middle to high northern latitudes. Our results suggest their findings may be less applicable to low latitudes.


Asunto(s)
Biodiversidad , Cambio Climático , Lluvia , Temperatura , Animales , Ecosistema , Geografía , Plantas , Dinámica Poblacional
12.
Glob Chang Biol ; 20(7): 2221-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24677405

RESUMEN

Shifts in species' distribution and abundance in response to climate change have been well documented, but the underpinning processes are still poorly understood. We present the results of a systematic literature review and meta-analysis investigating the frequency and importance of different mechanisms by which climate has impacted natural populations. Most studies were from temperate latitudes of North America and Europe; almost half investigated bird populations. We found significantly greater support for indirect, biotic mechanisms than direct, abiotic mechanisms as mediators of the impact of climate on populations. In addition, biotic effects tended to have greater support than abiotic factors in studies of species from higher trophic levels. For primary consumers, the impact of climate was equally mediated by biotic and abiotic mechanisms, whereas for higher level consumers the mechanisms were most frequently biotic, such as predation or food availability. Biotic mechanisms were more frequently supported in studies that reported a directional trend in climate than in studies with no such climatic change, although sample sizes for this comparison were small. We call for more mechanistic studies of climate change impacts on populations, particularly in tropical systems.


Asunto(s)
Biota , Cambio Climático , Animales , Aves/fisiología , Europa (Continente) , Peces/fisiología , Invertebrados/fisiología , Mamíferos/fisiología , América del Norte , Fenómenos Fisiológicos de las Plantas , Dinámica Poblacional
13.
Surg Obes Relat Dis ; 6(4): 399-407, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20655022

RESUMEN

BACKGROUND: In 2005, the American Society for Metabolic and Bariatric Surgery (ASMBS) nursing membership embarked on a journey to develop a specialty certification program for nurses caring for morbidly obese and bariatric surgical patients. In keeping with the certification industry best practices, a practice analysis study was conducted to create an empirically sound foundation for the new nursing specialty certification examination. METHODS: Task force meetings, subject-matter expert interviews, and an external review process were implemented to create a definition of the specialty in terms of 4 domains of practice, 45 nursing tasks, and 54 knowledge areas. The definition encompassed the work of bariatric nurse coordinators, bariatric program directors, and floor nurses caring for morbidly obese and bariatric surgical patients. A survey was administered to 1084 nurses practicing in the specialty to validate the domains, tasks, and knowledge. RESULTS: Some differences in the time spent in each of the domains and tasks were noted for the survey respondents in the different job roles. Nevertheless, the respondents for all job roles rated the domains and tasks moderately or highly important in optimizing the outcomes for morbidly obese and bariatric surgery patients. In addition, most respondents agreed that the 54 knowledge areas were acquired during the first 2 years of practice in the specialty. CONCLUSION: The survey results validated a specialized body of nursing knowledge rooted in the tasks that define professional practice. The results are being used to guide the development of a certification program for nurses practicing in the specialty and to provide guidance for education and training initiatives.


Asunto(s)
Cirugía Bariátrica/enfermería , Certificación/métodos , Educación en Enfermería/normas , Enfermeras Clínicas/educación , Enfermeras Practicantes/educación , Obesidad/enfermería , Cirugía Bariátrica/educación , Humanos , Enfermeras Clínicas/normas , Enfermeras Practicantes/normas , Obesidad/cirugía , Estados Unidos
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