883 research outputs found
Design and in Vitro Evaluation of a New Nano-Microparticulate System for Enhanced Aqueous-Phase Solubility of Curcumin
Curcumin, a yellow polyphenol derived from the turmeric Curcuma longa, has been associated with a diverse therapeutic potential including anti-inflammatory, antioxidant, antiviral, and anticancer properties. However, the poor aqueous solubility and low bioavailability of curcumin have limited its potential when administrated orally. In this study, curcumin was encapsulated in a series of novel nano-microparticulate systems developed to improve its aqueous solubility and stability. The nano-microparticulate systems are based entirely on biocompatible, biodegradable, and edible polymers including chitosan, alginate, and carrageenan. The particles were synthesized via ionotropic gelation. Encapsulating the curcumin into the hydrogel nanoparticles yielded a homogenous curcumin dispersion in aqueous solution compared to the free form of curcumin. Also, the in vitro release profile showed up to 95% release of curcumin from the developed nano-microparticulate systems after 9 hours in PBS at pH 7.4 when freeze-dried particles were used.CONACYTCUPIAPharmac
LRD spectral analysis of multifractional functional time series on manifolds
This paper introduces the statistical analysis of Jacobi frequency varying
Long Range Dependence (LRD) functional time series in connected and compact
two-point homogeneous spaces. The convergence to zero, in the Hilbert-Schmidt
operator norm, of the integrated bias of the periodogram operator is proved
under alternative conditions to the ones considered in Ruiz-Medina (2022).
Under this setting of conditions, weak-consistency of the minimum contrast
parameter estimator of the LRD operator holds. The case where the projected
manifold process can display Short Range Dependence (SRD) and LRD at different
manifold scales is also analyzed. The estimation of the spectral density
operator is addressed in this case. The performance of both estimation
procedures is illustrated in the simulation study undertaken within the
families of multifractionally integrated spherical functional
autoregressive-moving average (SPHARMA) processes.Comment: 34 pages; 19 Figure
Estimación de la heredabilidad para el peso al nacimiento y el peso al destete en la raza chino santandereano y sus cruces en el departamento de Santander
Con el objetivo de estimar los componentes de varianza y valores de heredabilidad para el peso
al nacimiento y el peso al destete en ejemplares de la raza criolla Chino Santandereano (CH), se
analizaron 277 registros entre los años 2008 y 2012 pertenecientes a las ganaderÃas Ojo de Agua
y Las Pampas en el Departamento de Santander. Se utilizó un modelo animal mixto que incluyó
los efectos fijos de año de nacimiento y destete, finca, sexo, época de nacimiento y destete,
número de parto, composición racial y el efecto aleatorio del padre; los análisis se realizaron
empleando los procedimientos GLM y MIXED del programa estadÃstico (SAS®, 9.0). Para el
peso al nacimiento se observó un promedio general de 27,20 ± 7,5 kg, encontrándose un efecto
significativo del año de nacimiento. Para el peso al destete se obtuvo un promedio general de
160,46 ± 62,9 kg, con efectos significativos de la finca y la composición racial. No se encontró
un efecto significativo del padre en la expresión de ninguna de las dos caracterÃsticas analizadas.
Las estimaciones de heredabilidad para el peso al nacimiento y el peso al destete fueron de 0,38
± 0,19 y 0,18 ± 0,14 respectivamente. Se concluye que es apropiado realizar selección genética
para la caracterÃstica peso al nacimiento, aunque se requiere mejorar las condiciones
medioambientales durante la fase del predestete a fin de obtener una mayor respuesta
productiva.In order to estimate the variance components and heritability values for birth weight and weaning
weight in specimen of the Chino Santandereano breed (CH), 277 records between 2008 and 2012
were analyzed belonging to herds Ojo de Agua and Las Pampas in the Department of Santander.
A mixed animal model that included the fixed effects of year of birth and weaning, farm, sex,
date of birth and weaning, parity, racial composition and the random effect of the sire was used;
analysis were performed using the GLM and MIXED (SAS ® 9.0) statistical program
procedures. For birth weight an overall average of 27.20 ± 7.5 kg was observed, finding a
significant effect of year of birth. Weaning weight for an overall average of 160.46 ± 62.9 kg,
with significant effects of the farm and the racial composition was obtained. No significant effect
of the father in the expression of any of the two characteristics analyzed was found. Heritability
estimates for birth weight were 0.38 ± 0.19 and for weaning weight of 0.18 ± 0.14. It concludes
that it is appropriate to conduct genetic selection taking into account the characteristic birth
weight and improvement of environmental conditions during the preweaning to obtain more
productive response.
KEYWORDS: Chino Santandereano, heritability, birth weight, weaning weigh
Monitoring of Tree Island Conditions in the Southern Everglades: The Effects of Hurricanes and Hydrology on the Status and Population Dynamics of Sixteen Tropical Hardwood Hammock Tree Islands
In 2005 we began a multi-year intensive monitoring and assessment study of tropical hardwood hammocks within two distinct hydrologic regions in Everglades National Park, under funding from the CERP Monitoring and Assessment Program. In serving as an Annual Report for 2010, this document, reports in detail on the population dynamics and status of tropical hardwood hammocks in Shark Slough and adjacent marl prairies during a 4-year period between 2005 and 2009. 2005-09 was a period that saw a marked drawdown in marsh water levels (July 2006 - July 2008), and an active hurricane season in 2005 with two hurricanes, Hurricane Katrina and Wilma, making landfall over south Florida. Thus much of our focus here is on the responses of these forests to annual variation in marsh water level, and on recovery from disturbance. Most of the data are from 16 rectangular permanent plots of 225-625 m2 , with all trees mapped and tagged, and bi-annual sampling of the tree, sapling, shrub, and herb layer in a nested design. At each visit, canopy photos were taken and later analyzed for determination of interannual variation in leaf area index and canopy openness. Three of the plots were sampled at 2-month intervals, in order to gain a better idea of seasonal dynamics in litterfall and litter turnover. Changes in canopy structure were monitored through a vertical line intercept method
E. coli
Escherichia coli meningitis is a frequent pathology in children younger than 3 years old, but is an uncommon disease in adults. E. coli infection is the main cause of intrahospital bacteremia as a consequence of the employment of different medical procedures. Our patient, male, 69 years old, presented with fever, progressive difficulty in breathing, and shivers 24 h after transrectal prostate biopsy, with an absence of any other symptoms. He received prophylactic treatment with ciprofloxacin and later empirical treatment with ampicillin and tobramicin. After that, the patient presented with fever, headache, behavioral changes, somnolence, disorientation, a fluctuating level of conscience, cutaneous widespread pallor, and acute urinary retention. On physical exploration, we observed generalized hypoventilation, Glasgow 10, stiffness of the neck, inconclusive Kernig; the remaining neurological exploration was normal. Systematic of blood: leukocytes = 8,510/mm3 (94.5% polymorphonuclear), platelet = 87,000/mm3, pH = 7.51, pCO2 = 28.8 mmHg, pO2 = 61 mmHg, O2 saturation = 93.8%, and remaining values were normal. Chest X- ray, cranial CT scan, urine cultures were normal. Blood culture: E. coli. CSF: glucose <0.4 g/l, total proteins = 3.05 g/l, PMN = 7 cells. Microscopic examination of the CSF: Gram-negative bacilli; CSF's culture: abundant E. coli. The case of acute meningitis by multiresistant E. coli after transrectal prostate biopsy presented demonstrates that antibiotic prevention with ciprofloxacin is not absolutely risk free. Besides the use of antibiotic prevention for multiresistant microorganisms, the urologist and other physicians involved in the procedure must not forget that the rate of major complications of transrectal prostate biopsy is 1%, especially when it is performed in patients who will not benefit from that biopsy
Characterization of the GGPP synthase gene family in Arabidopsis thaliana
Geranylgeranyl diphosphate (GGPP) is a key precursor of various isoprenoids that have diverse functions in plant metabolism and development. The annotation of the Arabidopsis thaliana genome predicts 12 genes to encode geranylgeranyl diphosphate synthases (GGPPS). In this study we analyzed GGPPS activity as well as the subcellular localization and tissue-specific expression of the entire protein family in A. thaliana. GGPPS2 (At2g18620), GGPPS3 (At2g18640), GGPPS6 (At3g14530), GGPPS7 (At3g14550), GGPPS8 (At3g20160), GGPPS9 (At3g29430), GGPPS10 (At3g32040) and GGPPS11 (At4g36810) showed GGPPS activity in Escherichia coli, similar to activities reported earlier for GGPPS1 (At1g49530) and GGPPS4 (At2g23800) (Zhu et al. in Plant Cell Physiol 38(3):357-361, 1997a; Plant Mol Biol 35(3):331-341, b). GGPPS12 (At4g38460) did not produce GGPP in E. coli. Based on DNA sequence analysis we propose that GGPPS5 (At3g14510) is a pseudogene. GGPPS-GFP (green fluorescent protein) fusion proteins of the ten functional GGPP synthases localized to plastids, mitochondria and the endoplasmic reticulum, with the majority of the enzymes located in plastids. Gene expression analysis using quantitative real time-PCR, GGPPS promoter-GUS (β-glucuronidase) assays and publicly available microarray data revealed a differential spatio-temporal expression of GGPPS genes. The results suggest that plastids and mitochondria are key subcellular compartments for the synthesis of ubiquitous GGPP-derived isoprenoid species. GGPPS11 and GGPPS1 are the major isozymes responsible for their biosynthesis. All remaining paralogs, encoding six plastidial isozymes and two cytosolic isozymes, were expressed in specific tissues and/or at specific developmental stages, suggesting their role in developmentally regulated isoprenoid biosynthesis. Our results show that of the 12 predicted GGPPS encoded in the A. thaliana genome 10 are functional proteins that can synthesize GGPP. Their specific subcellular location and differential expression pattern suggest subfunctionalization in providing GGPP to specific tissues, developmental stages, or metabolic pathway
Escolab: investigadores en el papel de divulgadores
EscoLab (http://www.escolab.cat) es una iniciativa del ICUB e IMEB del Ayuntamiento de Barcelona que brinda la oportunidad a jóvenes de interactuar con investigadores, conocer sus proyectos y participar en actividades a través de la visita sus centros de trabajo. Este estudio, realizado con la colaboración del ODC de la UAB, analiza la experiencia que ofrece Escolab para los investigadores participantes. En general, consideran que el programa funciona con éxito porque perciben que los jóvenes aprenden, se motivan, y mejoran la imagen que tienen de la ciencia. Los investigadoresdisfrutan devolviendo su conocimiento a la sociedad pero también reconocen sus limitaciones profesionales en materia de divulgación cientÃfica por lo que solicitan asesorÃa. Los resultados obtenidos permiten mejorar el impacto y calidad de las actividades de divulgación de EscoLab
Syndapin-2 mediated transcytosis of amyloid-β across the blood-brain barrier
A deficient transport of amyloid-β across the blood-brain barrier, and its diminished clearance from the brain, contribute to neurodegenerative and vascular pathologies, such as Alzheimer's disease and cerebral amyloid angiopathy, respectively. At the blood-brain barrier, amyloid-β efflux transport is associated with the low-density lipoprotein receptor-related protein 1. However, the precise mechanisms governing amyloid-β transport across the blood-brain barrier, in health and disease, remain to be fully understood. Recent evidence indicates that the low-density lipoprotein receptor-related protein 1 transcytosis occurs through a tubulation-mediated mechanism stabilized by syndapin-2. Here, we show that syndapin-2 is associated with amyloid-β clearance via low-density lipoprotein receptor-related protein 1 across the blood-brain barrier. We further demonstrate that risk factors for Alzheimer's disease, amyloid-β expression and ageing, are associated with a decline in the native expression of syndapin-2 within the brain endothelium. Our data reveals that syndapin-2-mediated pathway, and its balance with the endosomal sorting, are important for amyloid-β clearance proposing a measure to evaluate Alzheimer's disease and ageing, as well as a target for counteracting amyloid-β build-up. Moreover, we provide evidence for the impact of the avidity of amyloid-β assemblies in their trafficking across the brain endothelium and in low-density lipoprotein receptor-related protein 1 expression levels, which may affect the overall clearance of amyloid-β across the blood-brain barrier
Chemical modification of titanium precursor to obtain stable silica-titania sol: acetylacetone
[ES] La técnica Sol-Gel se ha utilizado para sintetizar una serie de sistemas multicomponentes, entre ellos SiO2 – TiO2. El mayor problema en la
obtención de geles multicomponentes estables es la desigual velocidad de hidrólisis y condensación que presentan los alcóxidos precursores
de los cationes de interés. En este trabajo se muestra cómo adicionando acetilacetona, acacH, al sistema TEOS – Ti(OBu)4 – H2O se puede
obtener un sol estable. Se tomaron diferentes concentraciones de los precursores de silicio y titanio y una sola concentración de acacH. Se
utilizó espectroscopia infrarroja, FTIR, para identificar los grupos funcionales presentes en el sistema y además se midió regularmente la
viscosidad para determinar cualitativamente el avance de la policondensación del sistema.[EN] Sol-gel processing has become a well established technique for producing ceramic powders or glasses. This processing has been utilized to
synthesize several interesting systems, e.g. the SiO2 – TiO2 system. A major concern in the stable multicomponent geles is that the hydrolysis
and condensation velocities are diferent for each precursor, TEOS and Ti(OBu)4 in this work. The chemical control of these reactions is currently
performed by adding complexing reagents that react with metal alkoxides at a molecular level, giving rise to new molecular precursors of
different structure, reactivity and functionanality. This paper shows that stable TEOS – Ti(OBu)4 – H2O sol can be reproducibly prepared in
the presence of acetylacetone. We shall then show that the acac behaves as a ligand, directly bonded to the titanium ion. Thus the formation
of precipitate is avoided. Infra-red spectroscopy (FTIR) and viscosity measures were used to demostrated this behaviour of the system.Este trabajo fue financiado a través de los proyectos COLCIENCIAS
N° 1103-05-605-93 y VRI-Universidad del Cauca N° 752. Agradecemos
a Ecopetrol-ICP la colaboración prestada con los estudios de
espectroscopia infrarroja y a la red CyTED VIII.E la ayuda económica
y técnica gracias a la cual A. Mafla pudo realizar su pasantÃa en el ICVCSIC
de Madrid-España.Peer reviewe
Functional Genomics of 5- to 8-Cell Stage Human Embryos by Blastomere Single-Cell cDNA Analysis
Blastomere fate and embryonic genome activation (EGA) during human embryonic development are unsolved areas of high scientific and clinical interest. Forty-nine blastomeres from 5- to 8-cell human embryos have been investigated following an efficient single-cell cDNA amplification protocol to provide a template for high-density microarray analysis. The previously described markers, characteristic of Inner Cell Mass (ICM) (n = 120), stemness (n = 190) and Trophectoderm (TE) (n = 45), were analyzed, and a housekeeping pattern of 46 genes was established. All the human blastomeres from the 5- to 8-cell stage embryo displayed a common gene expression pattern corresponding to ICM markers (e.g., DDX3, FOXD3, LEFTY1, MYC, NANOG, POU5F1), stemness (e.g., POU5F1, DNMT3B, GABRB3, SOX2, ZFP42, TERT), and TE markers (e.g., GATA6, EOMES, CDX2, LHCGR). The EGA profile was also investigated between the 5-6- and 8-cell stage embryos, and compared to the blastocyst stage. Known genes (n = 92) such as depleted maternal transcripts (e.g., CCNA1, CCNB1, DPPA2) and embryo-specific activation (e.g., POU5F1, CDH1, DPPA4), as well as novel genes, were confirmed. In summary, the global single-cell cDNA amplification microarray analysis of the 5- to 8-cell stage human embryos reveals that blastomere fate is not committed to ICM or TE. Finally, new EGA features in human embryogenesis are presented
- …