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1.
Proc Natl Acad Sci U S A ; 119(14): e2112886119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35363569

RESUMEN

Bacterial pathogen identification, which is critical for human health, has historically relied on culturing organisms from clinical specimens. More recently, the application of machine learning (ML) to whole-genome sequences (WGSs) has facilitated pathogen identification. However, relying solely on genetic information to identify emerging or new pathogens is fundamentally constrained, especially if novel virulence factors exist. In addition, even WGSs with ML pipelines are unable to discern phenotypes associated with cryptic genetic loci linked to virulence. Here, we set out to determine if ML using phenotypic hallmarks of pathogenesis could assess potential pathogenic threat without using any sequence-based analysis. This approach successfully classified potential pathogenetic threat associated with previously machine-observed and unobserved bacteria with 99% and 85% accuracy, respectively. This work establishes a phenotype-based pipeline for potential pathogenic threat assessment, which we term PathEngine, and offers strategies for the identification of bacterial pathogens.


Asunto(s)
Bacterias , Genoma Bacteriano , Aprendizaje Automático , Factores de Virulencia , Secuenciación Completa del Genoma , Bacterias/genética , Bacterias/patogenicidad , Fenotipo , Virulencia/genética , Factores de Virulencia/genética
2.
Bioinformatics ; 38(2): 397-403, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34570193

RESUMEN

MOTIVATION: Transcriptomics is a common approach to identify changes in gene expression induced by a disease state. Standard transcriptomic analyses consider differentially expressed genes (DEGs) as indicative of disease states so only a few genes would be treated as signals when the effect size is small, such as in brain tissue. For tissue with small effect sizes, if the DEGs do not belong to a pathway known to be involved in the disease, there would be little left in the transcriptome for researchers to follow up with. RESULTS: We developed RNA Solutions: Synthesizing Information to Support Transcriptomics (RNASSIST), a new approach to identify hidden signals in transcriptomic data by linking differential expression and co-expression networks using machine learning. We applied our approach to RNA-seq data of post-mortem brains that compared the Alcohol Use Disorder (AUD) group with the control group. Many of the candidate genes are not differentially expressed so would likely be ignored by standard transcriptomic analysis pipelines. Through multiple validation strategies, we concluded that these RNASSIST-identified genes likely play a significant role in AUD. AVAILABILITY AND IMPLEMENTATION: The RNASSIST algorithm is available at https://github.com/netrias/rnassist and both the software and the data used in RNASSIST are available at https://figshare.com/articles/software/RNAssist_Software_and_Data/16617250. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
ARN , Transcriptoma , ARN/genética , Perfilación de la Expresión Génica , RNA-Seq , Programas Informáticos , Análisis de Secuencia de ARN
3.
Appl Environ Microbiol ; 88(6): e0239321, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35138930

RESUMEN

Using the Wood-Ljungdahl pathway, acetogens can nonphotosynthetically fix gaseous C1 molecules, preventing them from entering the atmosphere. Many acetogens can also grow on liquid C1 compounds such as formate and methanol, which avoid the storage and mass transfer issues associated with gaseous C1 compounds. Substrate redox state also plays an important role in acetogen metabolism and can modulate products formed by these organisms. Butyribacterium methylotrophicum is an acetogen known for its ability to synthesize longer-chained molecules such as butyrate and butanol, which have significantly higher values than acetate or ethanol, from one-carbon (C1) compounds. We explored B. methylotrophicum's C1 metabolism by varying substrates, substrate concentrations, and substrate feeding strategies to improve four-carbon product titers. Our results showed that formate utilization by B. methylotrophicum favored acetate production and methanol utilization favored butyrate production. Cofeeding of both substrates produced a high butyrate titer of 4 g/liter when methanol was supplied in excess to formate. Testing of formate feeding strategies, in the presence of methanol, led to further increases in the butyrate to acetate ratio. Mixotrophic growth of liquid and gaseous C1 substrates expanded the B. methylotrophicum product profile, as ethanol, butanol, and lactate were produced under these conditions. We also showed that B. methylotrophicum is capable of producing caproate, a six-carbon product, presumably through chain elongation cycles of the reverse ß-oxidation pathway. Furthermore, we demonstrated butanol production via heterologous gene expression. Our results indicate that both selection of appropriate substrates and genetic engineering play important roles in determining titers of desired products. IMPORTANCE Acetogenic bacteria can fix single-carbon (C1) molecules. However, improvements are needed to overcome poor product titers. Butyribacterium methylotrophicum can naturally ferment C1 compounds into longer-chained molecules such as butyrate alongside traditional acetate. Here, we show that B. methylotrophicum can effectively grow on formate and methanol to produce high titers of butyrate. We improved ratios of butyrate to acetate through adjusted formate feeding strategies and produced higher-value six-carbon molecules. We also expanded the B. methylotrophicum product profile with the addition of C1 gases, as the organism produced ethanol, butanol, and lactate. Furthermore, we developed a transformation protocol for B. methylotrophicum to facilitate genetic engineering of this organism for the circular bioeconomy.


Asunto(s)
Monóxido de Carbono , Clostridium , Acetatos/metabolismo , Monóxido de Carbono/metabolismo , Clostridium/metabolismo , Metanol/metabolismo
4.
J Environ Sci (China) ; 116: 163-174, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35219415

RESUMEN

Due to the ever-tightening regulation on mercury emission in recent decades, there is an urgent need to develop novel materials for the removal of elemental mercury at coal-fired power plants. In this study, a series of MoS2 quantum dots (QDs)-based MoS2/HKUST-1 composite materials were prepared. It is found that MoS2 QDs were encapsulated by HKUST-1 and enhanced the crystallinity and specific surface area of HKUST-1. The MoS2/HKUST-1 showed excellent performance in catalytic oxidation of Hg0 as compared with pristine HKUST-1. It is found that surface layer of lattice oxygens is active and participates in Hg0 oxidation, while the consumption of surface oxygens then leads to the formation of oxygen vacancies on the surface. These vacancies are effective in the adsorption and dissociation of O2, which subsequently participates in the oxidation of Hg0. Moreover, the study on the influence of commonly seen gas components, such as SO2, NO, NH3 and H2O, etc., on Hg0 oxidation demonstrated that synergistic effects exist among these gas species. It is found that the presence of NO promotes the oxidation of Hg0 using oxygen as the oxidant.


Asunto(s)
Contaminantes Atmosféricos , Mercurio , Puntos Cuánticos , Catálisis , Carbón Mineral , Estructuras Metalorgánicas , Molibdeno , Oxidación-Reducción
5.
Cell Tissue Res ; 358(2): 551-66, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25130140

RESUMEN

Homeobox genes encode transcription factors that regulate embryonic development programs including organogenesis, axis formation and limb development. Previously, we identified and cloned a mouse double homeobox gene, Duxbl, whose homeodomain exhibits the highest identity (67 %) to human DUX4, a candidate gene of facioscapulohumeral muscular dystrophy (FSHD). Duxbl proteins have been shown to be expressed in elongated myocytes and myotubes of trunk and limb muscles during embryogenesis. In this study, we found that Duxbl maintained low expression levels in various adult muscles. Duxbl proteins were induced to express in activated satellite cells and colocalized with MyoG, a myogenic differentiating marker. Furthermore, Duxbl proteins were not detected in quiescent satellite cells but detected in regenerated myocytes and colocalized with MyoD and MyoG following cardiotoxin-induced muscle injury. Ectopic Duxbl overexpressions in C2C12 myoblast cells promoted cell proliferation through mainly enhancing cyclin D1 and hyper-phosphorylated retinoblastoma protein but reducing p21 expression. However, Duxbl overexpression in C2C12 cells inhibited myogenic differentiation by decreasing MyoD downstream gene expressions, including M-cadherin, MyoG, p21 and cyclin D3 but not MyoD itself. Duxbl overexpressions also promoted cell proliferation but blocked MyoD-induced myogenic conversion in multipotent mesenchymal C3H10T1/2 cells. In addition, results of a luciferase reporter assay suggest that Duxbl negatively regulated MyoG promoter activity through the proximal two E boxes. In conclusion, these results indicate that Duxbl may play a crucial role in myogenesis and postnatal muscle regeneration by activating and proliferating satellite and myoblast cells.


Asunto(s)
Diferenciación Celular , Proteínas de Homeodominio/genética , Proteína MioD/genética , Mioblastos/citología , Mioblastos/metabolismo , Factores de Transcripción/genética , Activación Transcripcional/genética , Envejecimiento/metabolismo , Animales , Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular/genética , Proliferación Celular , Técnica del Anticuerpo Fluorescente , Proteínas de Homeodominio/metabolismo , Humanos , Ratones , Desarrollo de Músculos , Proteína MioD/metabolismo , Miogenina/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Regeneración , Células Satélite del Músculo Esquelético/metabolismo , Factores de Transcripción/metabolismo
6.
Bioorg Med Chem Lett ; 24(1): 349-52, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24269123

RESUMEN

Employing a genetically modified yeast strain as a screening tool, 4-dimethylaminobenzoic acid (5) was isolated from the marine sediment-derived Streptomyces sp. CP27-53 as a weak yeast sirtuin (Sir2p) inhibitor. Using this compound as a scaffold, a series of disubstituted benzene derivatives were evaluated to elucidate the structure activity relationships for Sir2p inhibition. The results suggested that 4-alkyl or 4-alkylaminobenzoic acid is the key structure motif for Sir2p inhibitory activity. The most potent Sir2p inhibitor, 4-tert-butylbenzoic acid (20), among the tested compounds in this study turned out to be a weak but selective SIRT1 inhibitor. The calculated binding free energies between the selected compounds and the catalytic domain of SIRT1 were well correlated to their measured SIRT1 inhibitory activities.


Asunto(s)
Benzoatos/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Proteínas Reguladoras de Información Silente de Saccharomyces cerevisiae/antagonistas & inhibidores , Sirtuina 2/antagonistas & inhibidores , Streptomyces/química , Benzoatos/química , Benzoatos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad
7.
Sci Rep ; 13(1): 6021, 2023 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-37055450

RESUMEN

Limited data significantly hinders our capability of biothreat assessment of novel bacterial strains. Integration of data from additional sources that can provide context about the strain can address this challenge. Datasets from different sources, however, are generated with a specific objective and which makes integration challenging. Here, we developed a deep learning-based approach called the neural network embedding model (NNEM) that integrates data from conventional assays designed to classify species with new assays that interrogate hallmarks of pathogenicity for biothreat assessment. We used a dataset of metabolic characteristics from a de-identified set of known bacterial strains that the Special Bacteriology Reference Laboratory (SBRL) of the Centers for Disease Control and Prevention (CDC) has curated for use in species identification. The NNEM transformed results from SBRL assays into vectors to supplement unrelated pathogenicity assays from de-identified microbes. The enrichment resulted in a significant improvement in accuracy of 9% for biothreat. Importantly, the dataset used in our analysis is large, but noisy. Therefore, the performance of our system is expected to improve as additional types of pathogenicity assays are developed and deployed. The proposed NNEM strategy thus provides a generalizable framework for enrichment of datasets with previously collected assays indicative of species.


Asunto(s)
Bacterias , Redes Neurales de la Computación , Estados Unidos
8.
J Nat Prod ; 75(12): 2193-9, 2012 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-23167691

RESUMEN

A histone deacetylase (HDAC)-based yeast assay employing a URA3 reporter gene was applied as a primary screen to evaluate a marine-derived actinomycete extract library and identify human class III HDAC (SIRT) inhibitors. On the basis of the bioassay-guided purification, a new compound designated as streptosetin A (1) was obtained from one of the active strains identified through the yeast assay. The gross structure of the new compound was elucidated from the 1D and 2D NMR data. The absolute stereostructure of 1 was determined based on X-ray crystal structure analysis and simulation of ECD spectra using time-dependent density functional theory calculations. This compound showed weak inhibitory activity against yeast Sir2p and human SIRT1 and SIRT2.


Asunto(s)
Actinobacteria/química , Inhibidores de Histona Desacetilasas/aislamiento & purificación , Inhibidores de Histona Desacetilasas/farmacología , Pirrolidinonas/aislamiento & purificación , Pirrolidinonas/farmacología , Tetrahidronaftalenos/aislamiento & purificación , Tetrahidronaftalenos/farmacología , Cristalografía por Rayos X , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/clasificación , Humanos , Biología Marina , Conformación Molecular , Estructura Molecular , Pirrolidinonas/química , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Estereoisomerismo , Tetrahidronaftalenos/química , Factores de Tiempo
9.
Synth Biol (Oxf) ; 7(1): ysac012, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36035514

RESUMEN

Sequencing technologies, in particular RNASeq, have become critical tools in the design, build, test and learn cycle of synthetic biology. They provide a better understanding of synthetic designs, and they help identify ways to improve and select designs. While these data are beneficial to design, their collection and analysis is a complex, multistep process that has implications on both discovery and reproducibility of experiments. Additionally, tool parameters, experimental metadata, normalization of data and standardization of file formats present challenges that are computationally intensive. This calls for high-throughput pipelines expressly designed to handle the combinatorial and longitudinal nature of synthetic biology. In this paper, we present a pipeline to maximize the analytical reproducibility of RNASeq for synthetic biologists. We also explore the impact of reproducibility on the validation of machine learning models. We present the design of a pipeline that combines traditional RNASeq data processing tools with structured metadata tracking to allow for the exploration of the combinatorial design in a high-throughput and reproducible manner. We then demonstrate utility via two different experiments: a control comparison experiment and a machine learning model experiment. The first experiment compares datasets collected from identical biological controls across multiple days for two different organisms. It shows that a reproducible experimental protocol for one organism does not guarantee reproducibility in another. The second experiment quantifies the differences in experimental runs from multiple perspectives. It shows that the lack of reproducibility from these different perspectives can place an upper bound on the validation of machine learning models trained on RNASeq data. Graphical Abstract.

10.
Cell Rep Med ; 3(8): 100721, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35977462

RESUMEN

Understanding who is at risk of progression to severe coronavirus disease 2019 (COVID-19) is key to clinical decision making and effective treatment. We study correlates of disease severity in the COMET-ICE clinical trial that randomized 1:1 to placebo or to sotrovimab, a monoclonal antibody for the treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (ClinicalTrials.gov04545060). Laboratory parameters identify study participants at greater risk of severe disease, including a high neutrophil-to-lymphocyte ratio (NLR), a negative SARS-CoV-2 serologic test, and whole-blood transcriptome profiles. Sotrovimab treatment is associated with normalization of NLR and the transcriptomic profile and with a decrease of viral RNA in nasopharyngeal samples. Transcriptomics provides the most sensitive detection of participants who would go on to be hospitalized or die. To facilitate timely measurement, we identify a 10-gene signature with similar predictive accuracy. We identify markers of risk for disease progression and demonstrate that normalization of these parameters occurs with antibody treatment of established infection.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Anticuerpos Monoclonales Humanizados , Anticuerpos Neutralizantes , Humanos , ARN Viral , SARS-CoV-2
11.
J Bacteriol ; 193(20): 5833-40, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21840983

RESUMEN

Glucose is a carbon source that is capable of modulating the level of cyclic AMP (cAMP)-regulated genes. In the present study, we found that the stability of ompA mRNA was reduced in Escherichia coli when glucose (40 mM) was present in Luria-Bertani (LB) medium. This effect was associated with a low level of cAMP induced by the glucose. The results were confirmed with an adenylyl cyclase mutant with low levels of cAMP that are not modulated by glucose. Northern blot and Western blot analyses revealed that the host factor I (Hfq) (both mRNA and protein) levels were downregulated in the presence of cAMP. Furthermore, we showed that a complex of cAMP receptor protein (CRP) and cAMP binds to a specific P3(hfq) promoter region of hfq and regulates hfq expression. The regulation of the hfq gene was confirmed in vivo using an hfq-deficient mutant transformed with an exogenous hfq gene containing the promoter. These results demonstrated that expression of hfq was repressed by the CRP-cAMP complex. The presence of glucose resulted in increased Hfq protein levels, which decreased ompA mRNA stability. An additional experiment showed that cAMP also increased the stability of fur mRNA. Taken together, these results suggested that the repression of Hfq by cAMP may contribute to the stability of other mRNA in E. coli.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , AMP Cíclico/metabolismo , Regulación hacia Abajo , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Glucosa/metabolismo , Proteína de Factor 1 del Huésped/genética , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/metabolismo , Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Proteína de Factor 1 del Huésped/metabolismo , Estabilidad del ARN , ARN Mensajero/química , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
Front Microbiol ; 12: 695517, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34566906

RESUMEN

Clostridium thermocellum is a thermophilic bacterium recognized for its natural ability to effectively deconstruct cellulosic biomass. While there is a large body of studies on the genetic engineering of this bacterium and its physiology to-date, there is limited knowledge in the transcriptional regulation in this organism and thermophilic bacteria in general. The study herein is the first report of a large-scale application of DNA-affinity purification sequencing (DAP-seq) to transcription factors (TFs) from a bacterium. We applied DAP-seq to > 90 TFs in C. thermocellum and detected genome-wide binding sites for 11 of them. We then compiled and aligned DNA binding sequences from these TFs to deduce the primary DNA-binding sequence motifs for each TF. These binding motifs are further validated with electrophoretic mobility shift assay (EMSA) and are used to identify individual TFs' regulatory targets in C. thermocellum. Our results led to the discovery of novel, uncharacterized TFs as well as homologues of previously studied TFs including RexA-, LexA-, and LacI-type TFs. We then used these data to reconstruct gene regulatory networks for the 11 TFs individually, which resulted in a global network encompassing the TFs with some interconnections. As gene regulation governs and constrains how bacteria behave, our findings shed light on the roles of TFs delineated by their regulons, and potentially provides a means to enable rational, advanced genetic engineering of C. thermocellum and other organisms alike toward a desired phenotype.

13.
ACS Appl Bio Mater ; 4(2): 1395-1402, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35014490

RESUMEN

As enzymes in the outer membrane of the mitochondrion, monoamine oxidases (MAOs) can catalyze the oxidative deamination of monoamines in the human body. According to different substrates, MAOs can be divided into MAO-A and MAO-B. The imbalance of the MAO-A is associated with neurological degeneration, while excess MAO-B activity is closely connected with Parkinson's disease (PD) and Alzheimer's disease (AD); therefore, detection of MAOs is of great significance for the diagnosis and treatment of these diseases. This work reports the multiplexed detection of MAO-A and MAO-B using paper-based devices based on chemiluminescence (CL). The detection limits were 5.01 pg/mL for MAO-A and 8.50 pg/mL for MAO-B in human serum. In addition, we used paper-based devices to detect MAOs in human cells and tissue samples and found that the results of paper-based detection and Western blotting (WB) showed the same trend. While only one antibody can be incubated on the same membrane by WB, multiple antibodies incubated on the same paper enabled simultaneous detection of MAO-A and MAO-B by paper-based devices. The paper-based assay could be used for preliminary early screening of clinical samples for MAOs and can be extended as an alternative to WB for multiplexed detection of various proteins in disease cell or tissue samples.


Asunto(s)
Equipos y Suministros , Monoaminooxidasa/sangre , Monoaminooxidasa/metabolismo , Papel , Línea Celular , Humanos , Neoplasias/enzimología , Neoplasias/metabolismo
14.
Genomics Proteomics Bioinformatics ; 18(4): 443-454, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-33346084

RESUMEN

Chinese mitten crab (Eriocheir sinensis) is an important aquaculture species in Crustacea. Functional analysis, although essential, has been hindered due to the lack of sufficient genomic or transcriptomic resources. In this study, transcriptome sequencing was conducted on 59 samples representing diverse developmental stages (fertilized eggs, zoea, megalopa, three sub-stages of larvae, juvenile crabs, and adult crabs) and different tissues (eyestalk, hepatopancreas, and muscle from juvenile crabs, and eyestalk, hepatopancreas, muscle, heart, stomach, gill, thoracic ganglia, intestine, ovary, and testis from adult crabs) of E. sinensis. A comprehensive reference transcriptome was assembled, including 19,023 protein-coding genes. Hierarchical clustering based on 128 differentially expressed cuticle-related genes revealed two distinct expression patterns during the early larval developmental stages, demonstrating the distinct roles of these genes in "crab-like" cuticle formation during metamorphosis and cuticle calcification after molting. Phylogenetic analysis of 1406 one-to-one orthologous gene families identified from seven arthropod species and Caenorhabditis elegans strongly supported the hypothesis that Malacostraca and Branchiopoda do not form a monophyletic group. Furthermore, Branchiopoda is more phylogenetically closely related to Hexapoda, and the clade of Hexapoda and Branchiopoda and the clade of Malacostraca belong to the Pancrustacea. This study offers a high-quality transcriptome resource for E. sinensis and demonstrates the evolutionary relationships of major arthropod groups. The differentially expressed genes identified in this study facilitate further investigation of the cuticle-related gene expression networks which are likely associated with "crab-like" cuticle formation during metamorphosis and cuticle calcification after molting.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Animales , Crustáceos/genética , Femenino , Hepatopáncreas , Humanos , Filogenia
15.
Front Chem ; 8: 3, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32039161

RESUMEN

This study focuses on the use of a microwave reactor that combines biomass pyrolysis, at mild temperature, with catalytic reforming of the pyrolytic gas, using activated carbon, for generating hydrogen-rich synthesis gas. The traditional pyrolysis of biomass coupled with the reforming of its pyrolytic yields were also conducted using an electrically heated reactor. The bio-oil attained from conventional pyrolysis was higher in comparison to the yield from microwave pyrolysis. The reforming of the pyrolytic gas fraction led to reductions in bio-oil yield to <3.0 wt%, with a simultaneous increase in gaseous yields. An increase in the syngas and H2 selectivity was discovered with the reforming process such that the use of microwave pyrolysis with activated carbon reforming produced 85 vol% synthesis gas fraction containing 55 vol% H2 in comparison to the 74 vol% syngas fraction with 30 vol% H2 obtained without the reforming. Cracking reactions were improved with microwave heating, while deoxidation and dehydrogenation reactions were enhanced by activated carbon, which creates a reduction environment. Consequently, these reactions generated H2-rich syngas formation. The approach implemented in this study revealed higher H2, syngas yield and that the overall LHV of products has huge potential in the transformation of biomass into high-value synthesis gas.

16.
ACS Appl Mater Interfaces ; 11(33): 29604-29618, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31361112

RESUMEN

Diabetes and its complications have become a global challenge of public health. Herein, we aimed to develop a long-acting delivery system of lixisenatide (Lixi), a glucose-dependent antidiabetic peptide, based on an injectable hydrogel for the synchronous treatment of type 2 diabetes mellitus (T2DM) and associated complications. Two triblock copolymers, poly(ε-caprolactone-co-glycolic acid)-poly(ethylene glycol)-poly(ε-caprolactone-co-glycolic acid) and poly(d,l-lactic acid-co-glycolic acid)-poly(ethylene glycol)-poly(d,l-lactic acid-co-glycolic acid) possessing temperature-induced sol-gel transitions, were synthesized by us. Compared to the two single-component hydrogels, their 1/1 mixture hydrogel not only maintained the temperature-induced gelation but also exhibited a steadier degradation profile in vivo. Both in vitro and in vivo release studies demonstrated that the mixture hydrogel provided the sustained release of Lixi for up to 9 days, which was attributed to balanced electrostatic interactions between the positive charges in the peptide and the negative charges in the polymer carrier. The hypoglycemic efficacy of Lixi delivered from the mixture hydrogel after a single subcutaneous injection into diabetic db/db mice was comparable to that of twice-daily administrations of Lixi solution for up to 9 days. Furthermore, three successive administrations of the abovementioned gel system within a month significantly increased the plasma insulin level, lowered glycosylated hemoglobin, and improved the pancreatic function of the animals. These results were superior or equivalent to those of twice-daily injections of Lixi solution for 30 days, but the number of injections was markedly reduced from 60 to 3. Finally, an improvement in hyperlipidemia, augmentation of nerve fiber density, and enhancement of motor nerve conduction velocity in the gel formulation-treated db/db mice indicated that the sustained delivery of Lixi arrested and even ameliorated diabetic complications. These findings suggested that the Lixi-loaded mixture hydrogel has great potential for the treatment of T2DM with significant improvements in the health and quality of life of patients.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Péptidos/administración & dosificación , Péptidos/uso terapéutico , Animales , Rastreo Diferencial de Calorimetría , Dicroismo Circular , Preparaciones de Acción Retardada , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/metabolismo , Hidrogeles/química , Riñón/efectos de los fármacos , Riñón/metabolismo , Masculino , Ratones , Calidad de Vida , Ratas
17.
mBio ; 10(3)2019 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-31088924

RESUMEN

Trichomonas vaginalis, a prevalent sexually transmitted parasite, adheres to and induces cytolysis of human mucosal epithelial cells. We have characterized a hypothetical protein, TVAG_393390, with predicted tertiary structure similar to that of mammalian cadherin proteins involved in cell-cell adherence. TVAG_393390, renamed cadherin-like protein (CLP), contains a calcium-binding site at a position conserved in cadherins. CLP is surface localized, and its mRNA and protein levels are significantly upregulated upon parasite adherence to host cells. To test the roles of CLP and its calcium-binding dependency during host cell adherence, we first demonstrated that wild-type CLP (CLP) binds calcium with a high affinity, whereas the calcium-binding site mutant protein (CLP-mut) does not. CLP and CLP-mut constructs were then used to overexpress these proteins in T. vaginalis Parasites overexpressing CLP have ∼3.5-fold greater adherence to host cells than wild-type parasites, and this increased adherence is ablated by mutating the calcium-binding site. Additionally, competition with recombinant CLP decreased parasite binding to host cells. We also found that overexpression of CLP induced parasite aggregation which was further enhanced in the presence of calcium, whereas CLP-mut overexpression did not affect aggregation. Lastly, parasites overexpressing wild-type CLP induced killing of host cells ∼2.35-fold, whereas parasites overexpressing CLP-mut did not have this effect. These analyses describe the first parasitic CLP and demonstrate a role for this protein in mediating parasite-parasite and host-parasite interactions. T. vaginalis CLP may represent convergent evolution of a parasite protein that is functionally similar to the mammalian cell adhesion protein cadherin, which contributes to parasite pathogenesis.IMPORTANCE The adherence of pathogens to host cells is critical for colonization of the host and establishing infection. Here we identify a protein with no known function that is more abundant on the surface of parasites that are better at binding host cells. To interrogate a predicted function of this protein, we utilized bioinformatic protein prediction programs which allowed us to uncover the first cadherin-like protein (CLP) found in a parasite. Cadherin proteins are conserved metazoan proteins with central roles in cell-cell adhesion, development, and tissue structure maintenance. Functional characterization of this CLP from the unicellular parasite Trichomonas vaginalis demonstrated that the protein mediates both parasite-parasite and parasite-host adherence, which leads to an enhanced killing of host cells by T. vaginalis Our findings demonstrate the presence of CLPs in unicellular pathogens and identify a new host cell binding protein family in a human-infective parasite.


Asunto(s)
Cadherinas/genética , Células Epiteliales/metabolismo , Proteínas Protozoarias/metabolismo , Trichomonas vaginalis/patogenicidad , Cadherinas/metabolismo , Calcio/metabolismo , Adhesión Celular , Línea Celular , Células Epiteliales/parasitología , Femenino , Humanos , Membrana Mucosa/citología , Dominios Proteicos , Proteínas Protozoarias/genética , Activación Transcripcional , Regulación hacia Arriba
18.
Stud Health Technol Inform ; 264: 1972-1973, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31438434

RESUMEN

Globally, there is an expanding elderly population, and families are finding it increasingly challenging to coordinate care for their older family members. This paper reports on the usage patterns of InfoSAGE, an online private social network that has tools for communication and care coordination for elders and their families. This descriptive analysis describes the types of family networks using the platform and types of functionality most used by elders and their family members.


Asunto(s)
Comunicación , Familia , Anciano , Anciano Frágil , Humanos
19.
Stud Health Technol Inform ; 257: 352-357, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30741222

RESUMEN

The design of a mobile medication manager within a broader family and elder-centric collaboration platform faces challenges of usability and wide applicability. To inform the development and use cases of eldercare apps, we present the preliminary results of a usability study of an iOS and Android app intended for both family members and aging adults for the mobile management of medication lists. Seven participants were recorded during the performance of eight typical use-case scenarios of the medication portion of the InfoSAGE app. Audio and video recordings were analyzed for themes and events. The aim of this paper is to help inform future design choices for eldercare mobile apps.


Asunto(s)
Salud de la Familia , Cumplimiento de la Medicación , Aplicaciones Móviles , Adulto , Anciano , Humanos
20.
Biosci Biotechnol Biochem ; 72(11): 3021-4, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18997403

RESUMEN

The filamentous fungus Monascus pilosus was genetically transformed with a reporter plasmid, pMS-1.5hp, by aurintricarboxylic acid (ATA) treatment to obtain an efficient red-pigment producing mutant. The transformation efficiency of Monascus pilosus was higher with the ATA-treatment than with either a non-restriction-enzyme-mediated integration (REMI) or a REMI method. This valid and convenient random mutagenesis method shows that ATA can be applied in fungi for efficient genetic transformation.


Asunto(s)
Ácido Aurintricarboxílico/farmacología , Monascus/genética , Monascus/metabolismo , Pigmentación , Transformación Genética/efectos de los fármacos , Animales , Cloruro de Calcio/farmacología , Enzimas de Restricción del ADN/metabolismo , Humanos , Monascus/citología , Plásmidos/genética , Polietilenglicoles/farmacología , Protoplastos/efectos de los fármacos
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