Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Digit Health ; 10: 20552076241242795, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38571876

RESUMEN

Objective: This study aimed to determine the usability of the EMPOWER-SUSTAIN Self-Management Mobile App© and evaluate the factors associated with its usability among patients with cardiovascular risk factors in primary care. Methodology: This was a cross-sectional study, conducted among patients aged ≥ 18 years with cardiovascular risk factors attending a university primary care clinic. Patients were given the app to use for at least three months. Those who fulfilled the eligibility criteria were recruited. Data gathered were on sociodemographic, clinical characteristics, self-management support by doctors, utilisation of the app at home and social support in using the app. The previously translated and validated Malay version of the mHealth App Usability Questionnaire was used to measure usability. The mean usability score was calculated and linear regressions analysis was conducted to determine the factors associated with the usability of the app. Results: A total of 247 patients with at least one cardiovascular risk factor(s) were recruited. The mean age was 60.2 (±8.2). The majority were Malays (86.2%) and half of them were males (52.2%). The total mean (±SD) usability score was 5.26 (±0.67) indicating a high usability of the app. Usability of the app declined with increasing age in the simple linear regressions analysis. The multiple linear regressions yielded that being Malay (b = 0.31, 95% CI 0.08,0.54), using the app at home to understand their medications (b = 0.33, 95% CI 0.12,0.53) and having social support from family members and friends (b = 0.28, 95% CI 0.07,0.49) were significantly associated with higher usability of the app. Conclusion: The usability of the EMPOWER-SUSTAIN Self-Management Mobile App© was high among patients with cardiovascular risk factors in our primary care clinic. This finding supports the widespread use of this app among our patients. Involvement of family members and friends should be encouraged to improve the usability of the app.

2.
Biom J ; 65(8): e2100302, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37853834

RESUMEN

Human immunodeficiency virus (HIV) dynamics have been the focus of epidemiological and biostatistical research during the past decades to understand the progression of acquired immunodeficiency syndrome (AIDS) in the population. Although there are several approaches for modeling HIV dynamics, one of the most popular is based on Gaussian mixed-effects models because of its simplicity from the implementation and interpretation viewpoints. However, in some situations, Gaussian mixed-effects models cannot (a) capture serial correlation existing in longitudinal data, (b) deal with missing observations properly, and (c) accommodate skewness and heavy tails frequently presented in patients' profiles. For those cases, mixed-effects state-space models (MESSM) become a powerful tool for modeling correlated observations, including HIV dynamics, because of their flexibility in modeling the unobserved states and the observations in a simple way. Consequently, our proposal considers an MESSM where the observations' error distribution is a skew-t. This new approach is more flexible and can accommodate data sets exhibiting skewness and heavy tails. Under the Bayesian paradigm, an efficient Markov chain Monte Carlo algorithm is implemented. To evaluate the properties of the proposed models, we carried out some exciting simulation studies, including missing data in the generated data sets. Finally, we illustrate our approach with an application in the AIDS Clinical Trial Group Study 315 (ACTG-315) clinical trial data set.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Humanos , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Infecciones por VIH/epidemiología , Teorema de Bayes , Modelos Estadísticos , Carga Viral , VIH , Estudios Longitudinales
3.
J Am Soc Nephrol ; 33(12): 2174-2193, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36137753

RESUMEN

BACKGROUND: Variants in TBC1D8B cause nephrotic syndrome. TBC1D8B is a GTPase-activating protein for Rab11 (RAB11-GAP) that interacts with nephrin, but how it controls nephrin trafficking or other podocyte functions remains unclear. METHODS: We generated a stable deletion in Tbc1d8b and used microhomology-mediated end-joining for genome editing. Ex vivo functional assays utilized slit diaphragms in podocyte-like Drosophila nephrocytes. Manipulation of endocytic regulators and transgenesis of murine Tbc1d8b provided a comprehensive functional analysis of Tbc1d8b. RESULTS: A null allele of Drosophila TBC1D8B exhibited a nephrocyte-restricted phenotype of nephrin mislocalization, similar to patients with isolated nephrotic syndrome who have variants in the gene. The protein was required for rapid nephrin turnover in nephrocytes and for endocytosis of nephrin induced by excessive Rab5 activity. The protein expressed from the Tbc1d8b locus bearing the edited tag predominantly localized to mature early and late endosomes. Tbc1d8b was required for endocytic cargo processing and degradation. Silencing Hrs, a regulator of endosomal maturation, phenocopied loss of Tbc1d8b. Low-level expression of murine TBC1D8B rescued loss of the Drosophila gene, indicating evolutionary conservation. Excessive murine TBC1D8B selectively disturbed nephrin dynamics. Finally, we discovered four novel TBC1D8B variants within a cohort of 363 patients with FSGS and validated a functional effect of two variants in Drosophila, suggesting a personalized platform for TBC1D8B-associated FSGS. CONCLUSIONS: Variants in TBC1D8B are not infrequent among patients with FSGS. TBC1D8B, functioning in endosomal maturation and degradation, is essential for nephrin trafficking.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria , Síndrome Nefrótico , Podocitos , Ratones , Animales , Síndrome Nefrótico/genética , Síndrome Nefrótico/metabolismo , Drosophila , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Podocitos/metabolismo , Endocitosis , Endosomas/metabolismo
4.
Front Immunol ; 13: 822567, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572567

RESUMEN

Toxoplasma gondii infects one-third of the world population. For decades, it has been considered a silent lifelong infection. However, chronically T. gondii-infected persons may present psychiatric and neurocognitive changes as anxiety, depression, and memory loss. In a model of long-term chronic infection, behavioral alterations parallel neuroinflammation and systemic high cytokine levels, and may reflect brain cyst load. Recent findings support that in chronic infection an active parasite-host interplay involves an immune-mediated control of tissue cysts. Here, we tested the idea that etiological treatment in chronic phase may add advantage to intrinsic immune-mediated cyst control and impact behavioral changes. Thus, we combined sulfadiazine-plus-pyrimethamine (S+P), the first-choice therapy for toxoplasmosis, to study the association of brain cyst load and biological processes related to the immune response (neuroinflammation, blood-brain barrier -BBB- disruption and serum cytokine levels), with behavioral and neurocognitive changes of long-term chronic infection. Female C57BL/6 mice (H-2b) were infected (5 cysts, ME-49 strain) and treated with S+P from 30 to 60 days postinfection (dpi), compared with vehicle (Veh)-treated and noninfected controls. At endpoints (pre-therapy, 30 dpi; S+P therapy, 60 dpi; after ceased therapy, 90 dpi), independent groups were subjected to behavioral tests, and brain tissues and sera were collected. Multiple behavioral and neurocognitive changes were detected in the early (30 dpi) and long-term (60 and 90 dpi) chronic infection. S+P therapy resolved locomotor alterations, anxiety, and depressive-like behavior, partially or transiently ameliorated hyperactivity and habituation memory loss. Analysis after therapy cessation showed that S+P therapy reduced the number of stimuli required for aversive memory consolidation. S+P therapy resulted in reduced brain cyst load, neuroinflammation and BBB disruption, and lowered systemic Th1-cytokine levels. Correlation analysis revealed association between IFNγ, TNF and MCP-1/CCL2 serum levels, brain cyst load and behavioral and neurocognitive alterations. Moreover, principal-component analysis (PCA-2D and 3D projections) highlighted distinction between clusters (noninfected; Veh-treated and S+P-treated infected). Thus, our data suggest that S+P therapy added gain to intrinsic brain cyst control and, direct or indirectly, ameliorated inflammation-related alterations, traits associated with behavioral and neurocognitive alterations.


Asunto(s)
Encéfalo , Pirimetamina , Sulfadiazina , Toxoplasmosis , Animales , Encéfalo/parasitología , Citocinas , Femenino , Inflamación/tratamiento farmacológico , Trastornos de la Memoria/parasitología , Ratones , Ratones Endogámicos C57BL , Pirimetamina/farmacología , Pirimetamina/uso terapéutico , Sulfadiazina/farmacología , Sulfadiazina/uso terapéutico , Toxoplasmosis/tratamiento farmacológico , Toxoplasmosis/patología
5.
Kidney Int ; 101(6): 1216-1231, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35120995

RESUMEN

Risk variants of the apolipoprotein-L1 (APOL1) gene are associated with severe kidney disease, putting homozygous carriers at risk. Since APOL1 lacks orthologs in all major model organisms, a wide range of mechanisms frequently in conflict have been described for APOL1-associated nephropathies. The genetic toolkit in Drosophila allows unique in vivo insights into disrupted cellular homeostasis. To perform a mechanistic analysis, we expressed human APOL1 control and gain-of-function kidney risk variants in the podocyte-like garland cells of Drosophila nephrocytes and a wing precursor tissue. Expression of APOL1 risk variants was found to elevate endocytic function of garland cell nephrocytes that simultaneously showed early signs of cell death. Wild-type APOL1 had a significantly milder effect, while a control transgene with deletion of the short BH3 domain showed no overt phenotype. Nephrocyte endo-lysosomal function and slit diaphragm architecture remained unaffected by APOL1 risk variants, but endoplasmic reticulum (ER) swelling, chaperone induction, and expression of the reporter Xbp1-EGFP suggested an ER stress response. Pharmacological inhibition of ER stress diminished APOL1-mediated cell death and direct ER stress induction enhanced nephrocyte endocytic function similar to expression of APOL1 risk variants. We confirmed APOL1-dependent ER stress in the Drosophila wing precursor where silencing the IRE1-dependent branch of ER stress signaling by inhibition with Xbp1-RNAi abrogated cell death, representing the first rescue of APOL1-associated cytotoxicity in vivo. Thus, we uncovered ER stress as an essential consequence of APOL1 risk variant expression in vivo in Drosophila, suggesting a central role of this pathway in the pathogenesis of APOL1-associated nephropathies.


Asunto(s)
Enfermedades Renales , Podocitos , Animales , Apolipoproteína L1/genética , Drosophila/genética , Estrés del Retículo Endoplásmico/genética , Humanos , Enfermedades Renales/patología , Podocitos/patología
6.
Cell Rep ; 35(9): 109191, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34077727

RESUMEN

The vasculature is innervated by a network of peripheral afferents that sense and regulate blood flow. Here, we describe a system of non-peptidergic sensory neurons with cell bodies in the spinal ganglia that regulate vascular tone in the distal arteries. We identify a population of mechanosensitive neurons, marked by tropomyosin receptor kinase C (TrkC) and tyrosine hydroxylase in the dorsal root ganglia, which projects to blood vessels. Local stimulation of TrkC neurons decreases vessel diameter and blood flow, whereas systemic activation increases systolic blood pressure and heart rate variability via the sympathetic nervous system. Ablation of the neurons provokes variability in local blood flow, leading to a reduction in systolic blood pressure, increased heart rate variability, and ultimately lethality within 48 h. Thus, a population of TrkC+ sensory neurons forms part of a sensory-feedback mechanism that maintains cardiovascular homeostasis through the autonomic nervous system.


Asunto(s)
Presión Sanguínea/fisiología , Células Receptoras Sensoriales/fisiología , Animales , Conducta Animal , Fluoresceína/metabolismo , Ganglios Espinales/fisiología , Frecuencia Cardíaca/fisiología , Ratones Transgénicos , Receptor trkC/metabolismo
7.
J Am Soc Nephrol ; 30(12): 2338-2353, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31732614

RESUMEN

BACKGROUND: Mutations in about 50 genes have been identified as monogenic causes of nephrotic syndrome, a frequent cause of CKD. These genes delineated the pathogenetic pathways and rendered significant insight into podocyte biology. METHODS: We used whole-exome sequencing to identify novel monogenic causes of steroid-resistant nephrotic syndrome (SRNS). We analyzed the functional significance of an SRNS-associated gene in vitro and in podocyte-like Drosophila nephrocytes. RESULTS: We identified hemizygous missense mutations in the gene TBC1D8B in five families with nephrotic syndrome. Coimmunoprecipitation assays indicated interactions between TBC1D8B and active forms of RAB11. Silencing TBC1D8B in HEK293T cells increased basal autophagy and exocytosis, two cellular functions that are independently regulated by RAB11. This suggests that TBC1D8B plays a regulatory role by inhibiting endogenous RAB11. Coimmunoprecipitation assays showed TBC1D8B also interacts with the slit diaphragm protein nephrin, and colocalizes with it in immortalized cell lines. Overexpressed murine Tbc1d8b with patient-derived mutations had lower affinity for endogenous RAB11 and nephrin compared with wild-type Tbc1d8b protein. Knockdown of Tbc1d8b in Drosophila impaired function of the podocyte-like nephrocytes, and caused mistrafficking of Sns, the Drosophila ortholog of nephrin. Expression of Rab11 RNAi in nephrocytes entailed defective delivery of slit diaphragm protein to the membrane, whereas RAB11 overexpression revealed a partial phenotypic overlap to Tbc1d8b loss of function. CONCLUSIONS: Novel mutations in TBC1D8B are monogenic causes of SRNS. This gene inhibits RAB11. Our findings suggest that RAB11-dependent vesicular nephrin trafficking plays a role in the pathogenesis of nephrotic syndrome.


Asunto(s)
Proteínas de Unión al Calcio/genética , Mutación Missense , Síndrome Nefrótico/genética , Podocitos/metabolismo , Vesículas Transportadoras/fisiología , Proteínas de Transporte Vesicular/genética , Proteínas de Unión al GTP rab/metabolismo , Animales , Autofagia , Línea Celular Transformada , Perros , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Exocitosis , Silenciador del Gen , Células HEK293 , Humanos , Inmunoglobulinas/metabolismo , Células de Riñón Canino Madin Darby , Proteínas de la Membrana/metabolismo , Síndrome Nefrótico/metabolismo , Fenotipo , Mapeo de Interacción de Proteínas , Interferencia de ARN , ARN Interferente Pequeño/farmacología , Secuenciación del Exoma
8.
ACS Nano ; 12(8): 7936-7945, 2018 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-30059201

RESUMEN

Currently, a serious problem obstructing the large-scale clinical applications of fluorescence technique is the shallow penetration depth. Two-photon fluorescence microscopic imaging with excitation in the longer-wavelength near-infrared (NIR) region (>1100 nm) and emission in the NIR-I region (650-950 nm) is a good choice to realize deep-tissue and high-resolution imaging. Here, we report ultradeep two-photon fluorescence bioimaging with 1300 nm NIR-II excitation and NIR-I emission (peak ∼810 nm) based on a NIR aggregation-induced emission luminogen (AIEgen). The crab-shaped AIEgen possesses a planar core structure and several twisting phenyl/naphthyl rotators, affording both high fluorescence quantum yield and efficient two-photon activity. The organic AIE dots show high stability, good biocompatibility, and a large two-photon absorption cross section of 1.22 × 103 GM. Under 1300 nm NIR-II excitation, in vivo two-photon fluorescence microscopic imaging helps to reconstruct the 3D vasculature with a high spatial resolution of sub-3.5 µm beyond the white matter (>840 µm) and even to the hippocampus (>960 µm) and visualize small vessels of ∼5 µm as deep as 1065 µm in mouse brain, which is among the largest penetration depths and best spatial resolution of in vivo two-photon imaging. Rational comparison with the AIE dots manifests that two-photon imaging outperforms the one-photon mode for high-resolution deep imaging. This work will inspire more sight and insight into the development of efficient NIR fluorophores for deep-tissue biomedical imaging.


Asunto(s)
Colorantes Fluorescentes/química , Fotones , Animales , Femenino , Células HeLa , Humanos , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente , Simulación de Dinámica Molecular , Método de Montecarlo , Imagen Óptica , Espectroscopía Infrarroja Corta
9.
Microbiome ; 6(1): 100, 2018 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-29855347

RESUMEN

BACKGROUND: Microbially mediated oral diseases can signal underlying HIV/AIDS progression in HIV-infected adults. The role of the oral microbiota in HIV-infected youth is not known. The Adolescent Master Protocol of the Pediatric HIV/AIDS Cohort Study is a longitudinal study of perinatally HIV-infected (PHIV) and HIV-exposed, uninfected (PHEU) youth. We compared oral microbiome levels and associations with caries or periodontitis in 154 PHIV and 100 PHEU youth. RESULTS: Species richness and alpha diversity differed little between PHIV and PHEU youth. Group differences in average counts met the significance threshold for six taxa; two Corynebacterium species were lower in PHIV and met thresholds for noteworthiness. Several known periodontitis-associated organisms (Prevotella nigrescens, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Filifactor alocis) exhibited expected associations with periodontitis in PHEU youth, associations not observed in PHIV youth. In both groups, odds of caries increased with counts of taxa in four genera, Streptococcus, Scardovia, Bifidobacterium, and Lactobacillus. CONCLUSIONS: The microbiomes of PHIV and PHEU youth were similar, although PHIV youth seemed to have fewer "health"-associated taxa such as Corynebacterium species. These results are consistent with the hypothesis that HIV infection, or its treatment, may contribute to oral dysbiosis.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Caries Dental/microbiología , Infecciones por VIH/patología , Mucosa Bucal/microbiología , Periodontitis/microbiología , Saliva/microbiología , Adolescente , Adulto , Bacterias/genética , Niño , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Microbiota , ARN Ribosómico 16S/genética , Adulto Joven
10.
Horiz. sanitario (en linea) ; 16(3): 175-182, sep.-dic. 2017. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1002072

RESUMEN

Abstract Objective: The purpose of this study was the evaluation of an inter-cultural competence training program among first and sixth semester medical students at a university in Colombia. Materials and methods: This study utilized a quasi-experimental research design to evaluate an intercultural training program among 100 first and sixth semester medical students. Data were collected using the Intercultural Competency Scale and were analyzed using Wilcoxon Signal Range Test for related samples in SPSS version 21. Results: Significant differences were found in the areas of developing cultural sensitivity as well as developing understanding and respect for differences and diversity among first and six semester students in the experimental group. Conclusions: Findings suggest a strong need to incorporate intercultural training into the educational experience of medical students.


Resumen Objetivo: El objetivo de este estudio es evaluar un programa de capacitación en competencias interculturales entre estudiantes de medicina de primer y sexto semestre en una universidad de Colombia. Materiales y métodos: Este estudio utilizó un método de investigación cuasi-experimental para evaluar un programa de capacitación intercultural entre 100 estudiantes de primer y sexto semestre de medicina. Los datos se recolectaron utilizando la Escala de Competencia Intercultural y se analizaron utilizando la Prueba de Rango de Señales de Wilcoxón para muestras relacionadas en SPSS versión 21. Resultados: Se encontraron diferencias significativas en las áreas de desarrollo de la sensibilidad cultural, así como en el desarrollo de la comprensión y el respeto por las diferencias y la diversidad entre los estudiantes de primer y sexto semestre en el grupo experimental. Conclusiónes: Los hallazgos sugieren una fuerte necesidad de incorporar el entrenamiento intercultural en la experiencia educativa de los estudiantes de medicina.


Resumo Objectivo: O objetivo deste estudo é avaliar um programa de formação sobre competencias interculturais de estudantes de medicina do primeiro e sexto semestre numa universidade na Colõmbia. Materiais e métodos: Este estudo utilizou um método quase-experimental de pesquisa para avaliar um programa de formação intercultural entre os 100 caloiros e do sexto semestre de Medicina. Os dados foram recolhidos utilizando a Escala de Competencia Intercultural e foram analisados utilizando o Teste de Sinal de Wilcoxon para amostras em SPSS 21. Resultados: Foram encontradas diferenças significativas nas áreas de desenvolvimento da sensibilidade cultural, bem como o desenvolvimento da compreensáo e respeito pelas diferenças e diversidade entre estudantes caloiros e de sexto semestre do grupo experimental. Conclusões: Os resultados sugerem a necessidade de incorporar a formação em experiencia educacional intercultural na formação de estudantes de Medicina.


Résumé Objectif: L'objectif de cette étude est d'évaluer un programme de formation en compétences interculturelles parmi les étudiants en médecine de premier et sixieme semestre d'une université colombienne. Matériel et méthodes: Une méthode de recherche quasi-expérimentale a été utilisée pour évaluer un programme de formation interculturelle avec 100 étudiants de premier et sixieme semestre de médecine. Les données ont été recueillies a l'aide de l'Échelle de Compétence Interculturelle et analysées a l'aide du test de rangs signés de Wilcoxon pour échantillons appariés avec la version SPSS 21. Résultats: Des différences significatives dans les domaines du développement de la sensibilité culturelle ont été trouvées, ainsi que dans le développement de la compréhension et le respect des différences et de la diversité entre les étudiants du premier et du sixieme semestre du groupe expérimental. Conclusions: Les résultats suggerent l'importante nécessité d'intégrer l'entrainement interculturel dans l'expérience éducative interculturelle des étudiants en médecine.

11.
Genome Announc ; 4(5)2016 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-27795241

RESUMEN

Here, we present the draft genome sequence of the actinobacterium Curtobacterium sp. strain UCD-KPL2560, which was isolated from the running surface of an indoor track field house in Medford, MA, USA (42.409716°N, -71.115169°W). The genome assembly contains 3,480,487 bp in 156 contigs.

12.
J Calif Dent Assoc ; 44(7): 437-46, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27514155

RESUMEN

Dental caries is a major disease of the oral cavity with profound clinical significance. Caries results from a transition of a healthy oral microbiome into an acidogenic community of decreased microbial diversity in response to excessive dietary sugar intake. Microbiological cultivation, molecular identification, gene expression and metabolomic analyses show the importance of the entire microbial community in understanding the role of the microbiome in the pathology of caries.


Asunto(s)
Caries Dental/microbiología , Microbiota/fisiología , Boca/microbiología , Ácidos , Biopelículas , Esmalte Dental/microbiología , Dentina/microbiología , Humanos , Concentración de Iones de Hidrógeno , Interacciones Microbianas/fisiología , Caries Radicular/microbiología
13.
Am J Nurs ; 114(9): 60-2, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25166250

RESUMEN

EDITOR'S NOTE: From its first issue in 1900 through to the present day, AJN has unparalleled archives detailing nurses' work and lives over the last century. These articles not only chronicle nursing's growth as a profession within the context of the events of the day, but they also reveal prevailing societal attitudes about women, health care, and human rights. Today's nursing school curricula rarely include nursing's history, but it's a history worth knowing. To this end, From the AJN Archives will be a frequent column, containing articles selected to fit today's topics and times.This month's article, from the December 1903 issue, addresses school nursing. It was written by Lina L. Rogers, a nurse at the Henry Street Settlement in New York City, who, along with Settlement founder Lillian Wald, established the first school nurse program in the United States. At the time, physicians already visited the city's schools, but Rogers notes that they saw their role as simply one of excluding infected children from the classroom. The nurses' objective was, Rogers writes, "quite the reverse-namely, to keep the child in school." Over 110 years later, we are still trying to convince administrators that the services provided by school nurses are "a part of their educational system which they cannot neglect."


Asunto(s)
Servicios de Enfermería Escolar/historia , Historia del Siglo XX , Ciudad de Nueva York
14.
Mar Pollut Bull ; 79(1-2): 371-8, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24315739

RESUMEN

The present study investigated the concentration, distribution and speciation of metals (Fe, Mn, Cu, Pb, Co, Zn and Cr) in sediments of Mumbai region. Pearson's correlation matrix and cluster analyses showed good association of metals with grain size and organic matter. Factor analysis applied to the speciation data helped to identify the role of different sediment fractions in metal retention. The environmental risks of metals, evaluated by sediment quality guidelines, revealed some contamination in the region. However, the Individual and Global Contamination Factors and the Risk Assessment Code, suggested low risk to the aquatic environment, except of Mn in the creek sediments.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Metales/análisis , Contaminantes Químicos del Agua/análisis , Análisis por Conglomerados , India , Medición de Riesgo , Agua de Mar/química , Contaminación Química del Agua/estadística & datos numéricos
16.
Proc Natl Acad Sci U S A ; 110(24): 9824-9, 2013 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-23703908

RESUMEN

The Cyanobacteria Prochlorococcus and Synechococcus account for a substantial fraction of marine primary production. Here, we present quantitative niche models for these lineages that assess present and future global abundances and distributions. These niche models are the result of neural network, nonparametric, and parametric analyses, and they rely on >35,000 discrete observations from all major ocean regions. The models assess cell abundance based on temperature and photosynthetically active radiation, but the individual responses to these environmental variables differ for each lineage. The models estimate global biogeographic patterns and seasonal variability of cell abundance, with maxima in the warm oligotrophic gyres of the Indian and the western Pacific Oceans and minima at higher latitudes. The annual mean global abundances of Prochlorococcus and Synechococcus are 2.9 ± 0.1 × 10(27) and 7.0 ± 0.3 × 10(26) cells, respectively. Using projections of sea surface temperature as a result of increased concentration of greenhouse gases at the end of the 21st century, our niche models projected increases in cell numbers of 29% and 14% for Prochlorococcus and Synechococcus, respectively. The changes are geographically uneven but include an increase in area. Thus, our global niche models suggest that oceanic microbial communities will experience complex changes as a result of projected future climate conditions. Because of the high abundances and contributions to primary production of Prochlorococcus and Synechococcus, these changes may have large impacts on ocean ecosystems and biogeochemical cycles.


Asunto(s)
Ecosistema , Prochlorococcus/crecimiento & desarrollo , Agua de Mar/microbiología , Synechococcus/crecimiento & desarrollo , Algoritmos , Océano Atlántico , Predicción , Geografía , Océano Índico , Biología Marina/tendencias , Modelos Biológicos , Océano Pacífico , Densidad de Población , Dinámica Poblacional , Prochlorococcus/citología , Análisis de Regresión , Estaciones del Año , Synechococcus/citología , Temperatura
17.
Plant Physiol ; 162(2): 1073-91, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23613273

RESUMEN

Plants produce over 10,000 different diterpenes of specialized (secondary) metabolism, and fewer diterpenes of general (primary) metabolism. Specialized diterpenes may have functions in ecological interactions of plants with other organisms and also benefit humanity as pharmaceuticals, fragrances, resins, and other industrial bioproducts. Examples of high-value diterpenes are taxol and forskolin pharmaceuticals or ambroxide fragrances. Yields and purity of diterpenes obtained from natural sources or by chemical synthesis are often insufficient for large-volume or high-end applications. Improvement of agricultural or biotechnological diterpene production requires knowledge of biosynthetic genes and enzymes. However, specialized diterpene pathways are extremely diverse across the plant kingdom, and most specialized diterpenes are taxonomically restricted to a few plant species, genera, or families. Consequently, there is no single reference system to guide gene discovery and rapid annotation of specialized diterpene pathways. Functional diversification of genes and plasticity of enzyme functions of these pathways further complicate correct annotation. To address this challenge, we used a set of 10 different plant species to develop a general strategy for diterpene gene discovery in nonmodel systems. The approach combines metabolite-guided transcriptome resources, custom diterpene synthase (diTPS) and cytochrome P450 reference gene databases, phylogenies, and, as shown for select diTPSs, single and coupled enzyme assays using microbial and plant expression systems. In the 10 species, we identified 46 new diTPS candidates and over 400 putatively terpenoid-related P450s in a resource of nearly 1 million predicted transcripts of diterpene-accumulating tissues. Phylogenetic patterns of lineage-specific blooms of genes guided functional characterization.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Diterpenos/metabolismo , Biología Molecular/métodos , Plantas/genética , Plantas/metabolismo , Clonación Molecular , Minería de Datos , Bases de Datos Genéticas , Evolución Molecular , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
18.
Plant Physiol ; 161(2): 600-16, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23370714

RESUMEN

Diterpene resin acids (DRAs) are major components of pine (Pinus spp.) oleoresin. They play critical roles in conifer defense against insects and pathogens and as a renewable resource for industrial bioproducts. The core structures of DRAs are formed in secondary (i.e. specialized) metabolism via cycloisomerization of geranylgeranyl diphosphate (GGPP) by diterpene synthases (diTPSs). Previously described gymnosperm diTPSs of DRA biosynthesis are bifunctional enzymes that catalyze the initial bicyclization of GGPP followed by rearrangement of a (+)-copalyl diphosphate intermediate at two discrete class II and class I active sites. In contrast, similar diterpenes of gibberellin primary (i.e. general) metabolism are produced by the consecutive activity of two monofunctional class II and class I diTPSs. Using high-throughput transcriptome sequencing, we discovered 11 diTPS from jack pine (Pinus banksiana) and lodgepole pine (Pinus contorta). Three of these were orthologous to known conifer bifunctional levopimaradiene/abietadiene synthases. Surprisingly, two sets of orthologous PbdiTPSs and PcdiTPSs were monofunctional class I enzymes that lacked functional class II active sites and converted (+)-copalyl diphosphate, but not GGPP, into isopimaradiene and pimaradiene as major products. Diterpene profiles and transcriptome sequences of lodgepole pine and jack pine are consistent with roles for these diTPSs in DRA biosynthesis. The monofunctional class I diTPSs of DRA biosynthesis form a new clade within the gymnosperm-specific TPS-d3 subfamily that evolved from bifunctional diTPS rather than monofunctional enzymes (TPS-c and TPS-e) of gibberellin metabolism. Homology modeling suggested alterations in the class I active site that may have contributed to their functional specialization relative to other conifer diTPSs.


Asunto(s)
Transferasas Alquil y Aril/genética , Diterpenos/análisis , Evolución Molecular , Pinus/genética , Transferasas Alquil y Aril/clasificación , Transferasas Alquil y Aril/metabolismo , Secuencia de Aminoácidos , Biocatálisis , Ácidos Carboxílicos/análisis , Ácidos Carboxílicos/metabolismo , Cromatografía Liquida , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Diterpenos/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Datos de Secuencia Molecular , Fenantrenos/análisis , Fenantrenos/metabolismo , Filogenia , Pinus/clasificación , Pinus/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Especificidad de la Especie , Transcriptoma/genética
19.
Med J Malaysia ; 67(2): 212-3, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22822647

RESUMEN

Superglue in the ear as a foreign body is an uncommon presentation. We report the case of a lady who accidentally instilled superglue directly onto her tympanic membrane and presented five days later. We successfully removed the glue with acetone and managed to preserve the integrity of the tympanic membrane.


Asunto(s)
Acetona/administración & dosificación , Cianoacrilatos , Conducto Auditivo Externo , Cuerpos Extraños/terapia , Solventes/administración & dosificación , Adulto , Femenino , Humanos
20.
PLoS One ; 7(6): e37919, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22675498

RESUMEN

The oral microbiome, the complex ecosystem of microbes inhabiting the human mouth, harbors several thousands of bacterial types. The proliferation of pathogenic bacteria within the mouth gives rise to periodontitis, an inflammatory disease known to also constitute a risk factor for cardiovascular disease. While much is known about individual species associated with pathogenesis, the system-level mechanisms underlying the transition from health to disease are still poorly understood. Through the sequencing of the 16S rRNA gene and of whole community DNA we provide a glimpse at the global genetic, metabolic, and ecological changes associated with periodontitis in 15 subgingival plaque samples, four from each of two periodontitis patients, and the remaining samples from three healthy individuals. We also demonstrate the power of whole-metagenome sequencing approaches in characterizing the genomes of key players in the oral microbiome, including an unculturable TM7 organism. We reveal the disease microbiome to be enriched in virulence factors, and adapted to a parasitic lifestyle that takes advantage of the disrupted host homeostasis. Furthermore, diseased samples share a common structure that was not found in completely healthy samples, suggesting that the disease state may occupy a narrow region within the space of possible configurations of the oral microbiome. Our pilot study demonstrates the power of high-throughput sequencing as a tool for understanding the role of the oral microbiome in periodontal disease. Despite a modest level of sequencing (~2 lanes Illumina 76 bp PE) and high human DNA contamination (up to ~90%) we were able to partially reconstruct several oral microbes and to preliminarily characterize some systems-level differences between the healthy and diseased oral microbiomes.


Asunto(s)
Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Metagenoma/genética , Boca/microbiología , Enfermedades Periodontales/genética , Enfermedades Periodontales/microbiología , Actinomyces/efectos de los fármacos , Actinomyces/genética , Adulto , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Genes Bacterianos/genética , Variación Genética/efectos de los fármacos , Variación Genética/genética , Salud , Humanos , Redes y Vías Metabólicas/efectos de los fármacos , Redes y Vías Metabólicas/genética , Metagenoma/efectos de los fármacos , Metagenómica , Metales/farmacología , Persona de Mediana Edad , Boca/efectos de los fármacos , Periodontitis/genética , Periodontitis/microbiología , ARN Ribosómico 16S/genética , Estándares de Referencia , Factores de Virulencia/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...