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1.
Vaccine X ; 15: 100407, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38075434

RESUMEN

Vaccine-inducing immune thrombocytopenia, thrombosis, and bleeding emerge as infrequent and potential complications with mortality risk in healthy subjects. However, differences between survivors and non-survivors with SARS-CoV-2 vaccine-induced thrombotic thrombocytopenia (VITT) are unclear. Methods: According to the PRISMA statement, we conducted a systematic review and meta-analysis, and the protocol was registered in PROSPERO. The main objective is to identify differences among survivors and non-survivors of SARS-CoV-2 VITT patients. We systematically searched through PubMed, Scopus, and Web of Science. We included cohorts, case series, and case reports. We classified bleeding complications according to the ISTH definition. Statistics: unpaired Student's t-test or one-way ANOVA, Wilcoxon, and Kruskal-Wallis. Results: We systematically searched from January 2021 to June 2021 and identified 51 studies that included 191 patients. Non-survivors had the most severe thrombocytopenia (p 0.02) and lower fibrinogen measurements (p 0.01). Subjects vaccinated with mRNA vaccines (BNT162b2 and mRNA-1273) had an earlier onset of adverse events following immunization (p 0.001). We identified a higher trend of overall thrombotic events (p 0.001) in recipients of viral mechanism-dependent vaccines (Table 2). Non-survivors with cerebral venous sinus thrombosis (CVST) had more severe thrombocytopenia (p 0.01) than survivors with CVST. Finally, 61 % of survivors and 50 % with thrombosis received heparin. Conclusion: We identified more severe thrombocytopenia, lower fibrinogen measurements, and a higher trend of overall thrombotic events, including CVST and thrombotic storm, particularly with viral mechanisms-dependent vaccines in non-survivors VITT patients.

2.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210067, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36373912

RESUMEN

Reforestation is one of our most promising natural climate solutions, and one that addresses the looming biodiversity crisis. Tree planting can catalyse forest community reassembly in degraded landscapes where natural regeneration is slow, however, tree survival rates vary remarkably across projects. Building a trait-based framework for tree survival could streamline species selection in a way that generalizes across ecosystems, thereby increasing the effectiveness of the global restoration movement. We investigated how traits mediated seedling survival in a tropical dry forest restoration, and how traits were coordinated across plant structures. We examined growth and survival of 14 species for 2 years and measured six below-ground and 22 above-ground traits. Species-level survival ranged widely from 7.8% to 90.1%, and a model including growth rate, below-ground traits and their interaction explained more than 73% of this variation. A strong interaction between below-ground traits and growth rate indicated that selecting species with fast growth rates can promote establishment, but this effect was most apparent for species that invest in thick fine roots and deep root structures. Overall, results emphasize the prominent role of below-ground traits in determining early restoration outcomes, and highlight little above- and below-ground trait coordination, providing a path forward for tropical dry forest restoration efforts. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Asunto(s)
Ecosistema , Árboles , Bosques , Biodiversidad , Plantones , Clima Tropical
3.
Head Neck ; 44(10): 2316-2332, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35838064

RESUMEN

BACKGROUND: Carotid body tumor (CBT) is a rare neoplasm that has been increasingly studied during the last decades; nevertheless, it continues to be a topic of controversy. This review aims to provide an update on the general features of CBT and particularly review different treatment strategies and primary outcomes. METHODS: Data for this literature review were identified by PubMed, Scopus, and Medline. 93 articles from the initial search were included, as well as 28 relevant studies utilizing the snowballing method; totaling 121 articles about CBT. RESULTS: Main features such as anatomy, embryology, genetics, clinical presentation, and diagnosis of CBT are presented, followed by evidence of different treatment strategies such as radiotherapy, preoperative embolization, vascular resection, and vascular reconstruction. Main complications are also discussed. CONCLUSION: This review summarizes the most critical aspects regarding CBT. Future studies should compare different treatments to attain the best surgical results with lower morbidity rates.


Asunto(s)
Tumor del Cuerpo Carotídeo , Embolización Terapéutica , Tumor del Cuerpo Carotídeo/cirugía , Embolización Terapéutica/métodos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
4.
Ecol Appl ; 30(6): e02116, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32145123

RESUMEN

Microclimatic conditions change dramatically as forests age and impose strong filters on community assembly during succession. Light availability is the most limiting environmental factor in tropical wet forest succession; by contrast, water availability is predicted to strongly influence tropical dry forest (TDF) successional dynamics. While mechanisms underlying TDF successional trajectories are not well understood, observational studies have demonstrated that TDF communities transition from being dominated by species with conservative traits to species with acquisitive traits, the opposite of tropical wet forest. Determining how functional traits predict TDF tree species' responses to changing environmental conditions could elucidate mechanisms underlying tree performance during TDF succession. We implemented a 6-ha restoration experiment on a degraded Vertisol in Costa Rica to determine (1) how TDF tree species with different resource-use strategies performed along a successional gradient and (2) how ecophysiological functional traits correlated with tree performance in simulated successional stages. We used two management treatments to simulate distinct successional stages including: clearing all remnant vegetation (early-succession), or interplanting seedlings with no clearing (mid-succession). We crossed these two management treatments (cleared/interplanted) with two species mixes with different resource-use strategies (acquisitive/conservative) to examine their interaction. Overall seedling survival after 2 yr was low, 15.1-26.4% in the four resource-use-strategy × management-treatment combinations, and did not differ between the management treatments or resource-use-strategy groups. However, seedling growth rates were dramatically higher for all species in the cleared treatment (year 1, 69.1% higher; year 2, 143.3% higher) and defined resource-use strategies had some capacity to explain seedling performance. Overall, ecophysiological traits were better predictors of species' growth and survival than resource-use strategies defined by leaf and stem traits such as specific leaf area. Moreover, ecophysiological traits related to water use had a stronger influence on seedling performance in the cleared, early-successional treatment, indicating that the influence of microclimatic conditions on tree survival and growth shifts predictably during TDF succession. Our findings suggest that ecophysiological traits should be explicitly considered to understand shifts in TDF functional composition during succession and that using these traits to design species mixes could greatly improve TDF restoration outcomes.


Asunto(s)
Bosques , Clima Tropical , Costa Rica , Plantones , Árboles
5.
Glob Chang Biol ; 26(5): 3122-3133, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32053250

RESUMEN

Drought-related tree mortality is now a widespread phenomenon predicted to increase in magnitude with climate change. However, the patterns of which species and trees are most vulnerable to drought, and the underlying mechanisms have remained elusive, in part due to the lack of relevant data and difficulty of predicting the location of catastrophic drought years in advance. We used long-term demographic records and extensive databases of functional traits and distribution patterns to understand the responses of 20-53 species to an extreme drought in a seasonally dry tropical forest in Costa Rica, which occurred during the 2015 El Niño Southern Oscillation event. Overall, species-specific mortality rates during the drought ranged from 0% to 34%, and varied little as a function of tree size. By contrast, hydraulic safety margins correlated well with probability of mortality among species, while morphological or leaf economics spectrum traits did not. This firmly suggests hydraulic traits as targets for future research.


Asunto(s)
Sequías , El Niño Oscilación del Sur , Costa Rica , Bosques , Hojas de la Planta , Clima Tropical
6.
Anal Chim Acta ; 1085: 107-116, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31522724

RESUMEN

Magnetic actuation provides a low-cost, simple method for droplet manipulation on a digital microfluidic platform. The impetus to move the droplets on a low friction surface can come from internal superparamagnetic particles or paramagnetic salts. Recently, the use of microbes for bio-actuation has been established, where the thrust produced by the microbes can be exploited to exert the force required for droplet movement. This study presents biologically-driven magnetic actuation of droplets on a superhydrophobic surface using magnetotactic bacteria (MTB). MTB-droplets were impelled along various trajectories such as rectangular and figure-of-eight-shaped paths. Droplets were reproducibly actuated with speeds up of to 30 mm s-1. We demonstrated the ability to sequentially merge and mix multiple droplets by merging a 10 µL MTB droplet with two 4 µL colored droplets. The reorientation of MTB in the droplet enhanced mixing rate of the merged fluids by ∼40% compared with the control experiment where no actuation was used. Biologically-driven magnetic actuation was compared with actuation by superparamagnetic particles and paramagnetic salts, in terms of controllability and speed. MTB droplet was moved with the same average speed as other two methods and showed higher response time as the magnet acceleration increased. Lastly, MTB were used to perform a phosphatase assay using endogenous enzyme. The relative absorbance at 405 nm, indicating the production of the yellow product, increased over time and levels off after 75 min.


Asunto(s)
Magnetosomas/química , Magnetospirillum/química , Técnicas Analíticas Microfluídicas , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Propiedades de Superficie , Agua/química
7.
Ecol Evol ; 8(24): 12559-12575, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30619565

RESUMEN

The diverse offspring of clonal species differ in their dispersability, influencing genotypic diversity and clonal structure. Here, we determined dispersal patterns and their impact on genetic structure in Opuntia microdasys, a self-incompatible cactus with three dispersal units (one sexual and two clonal). We analyzed dispersal, using experiments at three populations, and assessed multilocus genotypes (ISSR markers) of all individuals in 10 clumps per population with known reproductive origin (sexual or clonal). Genotype of all samples, population structure, and migration between clumps and populations were assessed with GenAlEx and GenoDive, assuming higher genotypic diversity and migration when sexual reproduction is more frequent. We determined the most likely number of genetic clusters with STRUCTURE and geneland. Dispersal differed among populations; primary dispersal occurred at short distances and was farthest on steep slopes, and dispersal distance increased after secondary dispersal. Clumps had 116 different multilocus genotypes in three spatially explicit genetic clusters. We detected genetic structure at small scale, genotypic diversity among clumps varied between populations; diversity decreased while clonal dominance increased, and the most variation occurred among clumps. Genetic structure was moderate, suggesting gene flow by seed dispersal allows slight differentiation among population at large scales. Genetic diversity within clumps was the lowest because dispersal of clonal propagules was limited and caused genotypic dominance at local scale. However, the combined dispersal pattern of sexual and clonal dispersal units is fine-tuned by environmental factors, generating a range of genetic diversity among clusters and populations. This pattern suggests that genetic structure of clonal plants is more dynamic than thought, and dispersal of different types of offspring affects genetic structure at many scales.

8.
Acta Crystallogr F Struct Biol Commun ; 70(Pt 11): 1472-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25372812

RESUMEN

Prior studies have indicated that MJ1099 from Methanocaldococcus jannaschii has roles in the biosynthesis of tetrahydromethanopterin and methanofuran, two key cofactors of one-carbon (C1) metabolism in diverse organisms including the methanogenic archaea. Here, the structure of MJ1099 has been solved to 1.7 Šresolution using anomalous scattering methods. The results indicate that MJ1099 is a member of the TIM-barrel superfamily and that it is a homohexamer. Bioinformatic analyses identified a potential active site that is highly conserved among MJ1099 homologs and the key amino acids involved were identified. The results presented here should guide further studies of MJ1099 including mechanistic studies and possibly the development of inhibitors that target the methanogenic archaea in the digestive tracts of humans and that are a source of the greenhouse gas methane.


Asunto(s)
Proteínas Bacterianas/química , Furanos/química , Methanocaldococcus/enzimología , Pterinas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión/fisiología , Cristalografía , Furanos/metabolismo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Pterinas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
9.
Rev. costarric. cienc. méd ; 23(1/2): 55-68, ene.-jun. 2002. ilus
Artículo en Español | LILACS | ID: lil-325338

RESUMEN

El cromo es un elemento esencial para humanos y animales ya que tiene una función preponderante en el metabolismo de la insulina como factor de tolerancia a la glucosa (FTG). Su deficiencia genera un deterioro del metabolismo de la glucosa por la mala eficiencia de la insulina. Debido a la importanica de este elemento se realizó una revisión bibliográfica exhaustiva y se presentan algunos estudios realizados con animales de laboratorio y seres humanos, que demuestran con resultados el efecto del cromo sobre el mejoramiento del estado de pacientes diabéticos no insulino dependientes. Se presentan tres sustancias como formas biológicamente activas del cromo: un material rico en cromo conocido como factor de tolerancia de la glucosa, el picolinato de cromo, y una sustancia de bajo peso molecular LMWCr en sus formas apo y holo que contiene cromo que se en laza al receptor de insulina y mejora su actividad. También se presenta información sobre el estado de la diabetes en Costa Rica.


Asunto(s)
Cromo , Diabetes Mellitus , Glucosa , Insulina , Costa Rica
10.
Rev Med Chil ; 130(12): 1349-57, 2002 Dec.
Artículo en Español | MEDLINE | ID: mdl-12611235

RESUMEN

BACKGROUND: Subserous gallbladder carcinoma is difficult to diagnose and treat. There are no tissue markers with prognostic value in this type of tumor. AIM: To study the immunohistochemical expression of E-cadherin alpha and beta catenin in subserous gallbladder carcinoma. PATIENTS AND METHODS: One hundred seventeen subjects (103 women and 14 men aged 62 and 69 years as a mean, respectively), were studied. Thirty five gallbladder samples without evidence of cancer were used as controls. Expression of markers was studied with standard immunohistochemical techniques for formalin fixed and paraffin embedded tissue. RESULTS: Ninety seven percent of tumors were adenocarcinoma. A lower or absent expression of E-cadherin, alpha catenin and beta catenin was observed in 26, 33 and 29% of tumors, respectively. Actuarial five years survival was 37%. No association between macroscopic features of the tumor and survival was observed. Well differentiated tumors had a 73% survival, whereas less differentiated tumors had a 30% survival. Tumors with a normal expression of the markers had a slightly better survival, although not significant (p = 0.06). CONCLUSIONS: Approximately 30% of subserous gallbladder carcinoma have an abnormal expression of E-cadherin, alpha catenin and beta catenin. This abnormal expression has no relationship with prognosis and is probably secondary to the aberrant genic expression of the tumor.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Cadherinas/metabolismo , Cistadenocarcinoma Seroso/metabolismo , Proteínas del Citoesqueleto/metabolismo , Neoplasias de la Vesícula Biliar/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Cistadenocarcinoma Seroso/inmunología , Femenino , Neoplasias de la Vesícula Biliar/inmunología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia , Transactivadores/metabolismo , alfa Catenina , beta Catenina
12.
Guatem. pediátr ; 28(1): 14-6, feb.-mar. 1997. tab
Artículo en Español | LILACS | ID: lil-200215

RESUMEN

Objetivo: Determinar la relación entre la suplementación con sulfato ferroso y el rendimiento escolar. Metodología: estudio comparativo experimental. Durante el ciclo escolar se realizó suplementación diaria, de lunes a viernes, con 60 mg. de sulfato ferroso a 217 alumnas y otro grupo de 115 alumnas y otro grupo de 115 alumnas no lo recibió, por lo que se constituyó como grupo control. En todas las alumnas se midieron niveles de Hb y Ferritina sérica al inicio y al final del estudio, así como notas académicas. Resultados: se demostró que no existió relación entre mejora de anemia y rendimiento académico. Las niñas con anemia que fueron suplementadas, a pesar de continuar con niveles bajos de Hb y Ferritina, aprobaron el ciclo escolar en un porcentaje mayor (91/100), en comparación del grupo de niñas con anemia que no recibieron suplementación (20/100). Conclusiones: El estudio mostró que niñas con anemia que no recibieron suplementación, reprobaron en mayor porcentaje que las que si lo recibieron (p <0.01), pero esta mejora del rendimiento académico fue independiente del incremento en los niveles de Hb y Ferritina


Asunto(s)
Humanos , Femenino , Anemia Hipocrómica/diagnóstico , Rendimiento Escolar Bajo
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