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1.
Biochem Biophys Res Commun ; 717: 150045, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38718572

RESUMO

The ubiquitin-proteasome system (UPS) plays a key role in maintaining cellular protein homeostasis and participates in modulating various cellular functions. Target of rapamycin (TOR), a highly conserved Ser/Thr kinase found across species from yeasts to humans, forms two multi-protein complexes, TORC1 and TORC2, to orchestrate cellular processes crucial for optimal growth, survival, and stress responses. While UPS-mediated regulation of mammalian TOR complexes has been documented, the ubiquitination of yeast TOR complexes remains largely unexplored. Here we report a functional interplay between the UPS and TORC2 in Saccharomyces cerevisiae. Using avo3-2ts, a temperature-sensitive mutant of the essential TORC2 component Avo3 exhibiting TORC2 defects at restrictive temperatures, we obtained evidence for UPS-dependent protein degradation and downregulation of the TORC2 component Avo2. Our results established the involvement of the E3 ubiquitin ligase Ubr1 and its catalytic activity in mediating Avo2 degradation in cells with defective Avo3. Coimmunoprecipitation revealed the interaction between Avo2 and Ubr1, indicating Avo2 as a potential substrate of Ubr1. Furthermore, depleting Ubr1 rescued the growth of avo3-2ts cells at restrictive temperatures, suggesting an essential role of Avo2 in sustaining cell viability under heat stress and/or TORC2 dysfunction. This study uncovers a role of UPS in yeast TORC2 regulation, highlighting the impact of protein degradation control on cellular signaling.


Assuntos
Regulação para Baixo , Alvo Mecanístico do Complexo 2 de Rapamicina , Complexo de Endopeptidases do Proteassoma , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Ubiquitina-Proteína Ligases , Ubiquitina , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
2.
J Adv Res ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38548265

RESUMO

INTRODUCTION: The clinical presentations of dry eye disease (DED) and depression (DEP) often comanifest. However, the robustness and the mechanisms underlying this association were undetermined. OBJECTIVES: To this end, we set up a three-segment study that employed multimodality results (meta-analysis, genome-wide association study [GWAS] and Mendelian randomization [MR]) to elucidate the association, common pathways and causality between DED and DEP. METHODS: A meta-analysis comprising 26 case-control studies was first conducted to confirm the DED-DEP association. Next, we performed a linkage disequilibrium (LD)-adjusted GWAS and targeted phenotype association study (PheWAS) in East Asian TW Biobank (TWB) and European UK Biobank (UKB) populations. Single-nucleotide polymorphisms (SNPs) were further screened for molecular interactions and common pathways at the functional gene level. To further elucidate the activated pathways in DED and DEP, a systemic transcriptome review was conducted on RNA sequencing samples from the Gene Expression Omnibus. Finally, 48 MR experiments were implemented to examine the bidirectional causation between DED and DEP. RESULTS: Our meta-analysis showed that DED patients are associated with an increased DEP prevalence (OR = 1.83), while DEP patients have a concurrent higher risk of DED (OR = 2.34). Notably, cross-disease GWAS analysis revealed that similar genetic architecture (rG = 0.19) and pleiotropic functional genes contributed to phenotypes in both diseases. Through protein-protein interaction and ontology convergence, we summarized the pleiotropic functional genes under the ontology of immune activation, which was further validated by a transcriptome systemic review. Importantly, the inverse variance-weighted (IVW)-MR experiments in both TWB and UKB populations (p value <0.001) supported the bidirectional exposure-outcome causation for DED-to-DEP and DEP-to-DED. Despite stringent LD-corrected instrumental variable re-selection, the bidirectional causation between DED and DEP remained. CONCLUSION: With the multi-modal evidence combined, we consolidated the association and causation between DED and DEP.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36141811

RESUMO

High-efficiency particulate air (HEPA) filters is a potential tool used to remove fine particles and improve indoor air quality. This study aims to analyze the real-world efficacy of portable HEPA air cleaners in a household environment. Laser light dispersion PM2.5 sensors are used to continuously monitor the indoor and outdoor PM2.5 level before and after HEPA air cleaner filtration. Overall, HEPA air cleaners significantly reduce the indoor PM2.5 level (33.5 ± 10.3 vs. 17.2 ± 10.7 µg/m3, mean difference (MD) = -16.3 µg/m3, p < 0.001) and indoor/outdoor PM2.5% (76.3 ± 16.8 vs. 38.6 ± 19.8%, MD = -37.7%, p < 0.001). The efficacy to reduce PM2.5 is strongest in three machines with medium-flow setting group (indoor PM2.5 MD: -26.5 µg/m3, indoor/outdoor PM2.5 percentage MD: -56.4%). Multiple linear regression demonstrates that outdoor PM2.5, machine number, airflow speed, and window ventilation are significant factors associated with indoor PM2.5 concentrations (R = 0.879) and percentage of the indoor/outdoor PM2.5 ratio (R = 0.808). HEPA air cleaners can effectively improve indoor PM2.5 air pollution. Adequate air cleaner machine numbers, appropriate airflow, and window ventilation limitations are important to achieve the best efficacy of the HEPA air cleaner.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Ar Condicionado , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poeira , Material Particulado/análise
4.
Invest New Drugs ; 40(6): 1165-1172, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35943683

RESUMO

Non-medical use of ketamine as an adulterant to ecstasy is more prevalent than amphetamine in Taiwan. Ketamine's effect on immunosuppression might play some functional role in tumor growth, while it is still controversial whether ketamine abuse could increase tumor growth or not. This study aimed to investigate the influence of ketamine addiction in breast tumors and related gene expressions. The effect of ketamine treatment on proliferation, colony formation, migration, and invasion of triple-negative breast cancer cell line EO771 was examined. In addition, a ketamine addiction mice model was established by intraperitoneal injection (IP) of ketamine in mice and used to investigate the effects of ketamine addiction on tumor growth and the possible mechanisms. In the in vitro studies, ketamine treatment at different concentrations did not affect EO771 cell proliferation and colony formation. But ketamine did enhance migration and invasion of EO771 cells. The in vivo experiments showed significantly increased breast tumor volume and weight in ketamine-addicted mice than in normal saline groups. miR-27b-3p level, human epidermal growth factor receptor 2 (HER2), and epidermal growth factor receptor (EGFR) significantly increased in tumors of ketamine addiction mice compared to control mice. In vivo evidence showed that Ketamine might increase tumor growth on the tumor microenvironment, and miR-27b-3p, HER2, and EGFR might play a role in the process.


Assuntos
Neoplasias da Mama , Ketamina , MicroRNAs , Humanos , Camundongos , Animais , Feminino , Ketamina/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células/genética , Microambiente Tumoral , Receptores ErbB/genética , Receptores ErbB/metabolismo
5.
Pediatr Neonatol ; 63(3): 269-275, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35305927

RESUMO

BACKGROUND: The inconsistency in decisions to commence oral feeding indicates that health professionals require clearer guidelines to determine when to initiate oral feeding in preterm infants. This study applied the Taiwan version of Preterm Oral Feeding Readiness Assessment Scale (TW-POFRAS) to clinical decision-making, especially for preterm infants with a birth weight less than 1,500 g or gestational age (GA) less than 32 weeks. METHODS: This was a single-center observational cross-sectional study and 81 preterm infants were recruited. Lengths of stay from admission to initial one-meal oral feeding, to one-day all-meal oral feeding, and to discharge were analyzed. Scale scores, physician orders, and smooth oral intake of 5 mL of milk were analyzed. Kappa coefficients were examined to determine concordances within the results. RESULTS: At least moderate concordance was evident (k = 0.492). Most preterm infants can begin to consume one meal of the least 5 mL of milk smoothly and proceed to consume a full day of meals with a week; they are typically discharged from the hospital within a month, except for those with a birth weight less than 1,500 g or a GA less than 32 weeks. For 17 of 81 participants, assessment results for physician orders, 5-mL milk consumption, and scale scores were inconsistent. Participants with a birth weight less than 1,500 g or GA less than 32 weeks were able to meet the 5-mL standard by the postmenstrual age of 35 weeks, at latest. CONCLUSION: We recommend that TW-POFRAS should be used in conjunction with physicians' clinical decision-making for oral feeding readiness for preterm infants in the NICU.


Assuntos
Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Peso ao Nascer , Estudos Transversais , Humanos , Lactente , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Alta do Paciente
6.
J Pediatr Nurs ; 59: e84-e92, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33648837

RESUMO

PURPOSE: A successful transition from gavage to full oral feeding is a decisive indicator for discharging premature infants from the neonatal intensive care unit. A clinically useful measure of oral feeding readiness would help nurses initiate implementation of the cue-based feeding model in Taiwan. The study aimed to assess the validity and reliability of the Traditional Chinese Preterm Oral Feeding Readiness Assessment Scale (TC-POFRAS). DESIGN AND METHODS: 81 preterm infants were enrolled and assessed by TC-POFRAS regarding their oral feeding readiness. This study included two phases. Phase 1 conducted a cross language validation procedure and item-level content validity indices (I-CVIs) for content validity were estimated. In phase 2, Cronbach's alpha for internal consistency at each category and total scale levels were estimated. A receiver operating characteristic (ROC) curve was estimated to explore the scale's performance. The optimal cut-off value of TC-POFRAS was identified by the best Youden's Index [maximum (sensitivity + specificity - 1)]. RESULTS: All of the I-CVIs were 1.00. The whole Cronbach's alpha for internal consistency was 0.804 (95% CI = 0.736-0.862), and Cronbach's alpha values were between 0.538 (95% = 0.332-0.689) and 0.687 (95%CI = 0.572-0.781) for categories. The area under ROC was 92.2%, and an optimal cut-off value of TC-POFRAS was 29 (sensitivity: 0.938, specificity: 0.941). CONCLUSIONS: The TC-POFRAS has been verified to be an effective and accurate instrument to determine the initiation of oral feeding in preterm infants. PRACTICE IMPLICATIONS: The TC-POFRAS is an appropriate and complementary assessment instrument for professionals to conveniently use in clinical practice.


Assuntos
Recém-Nascido Prematuro , Comportamento de Sucção , Alimentação com Mamadeira , Humanos , Lactente , Recém-Nascido , Psicometria , Reprodutibilidade dos Testes , Taiwan
7.
Cancers (Basel) ; 12(10)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019722

RESUMO

Increased ROS proto-oncogene 1 (ROS1) expression has been implicated in the invasiveness of human oral squamous cell carcinoma (OSCC). The cellular distribution of ROS1 has long-been assumed at the plasma membrane. However, a previous work reported a differential cellular distribution of mutant ROS1 derived from chromosomal translocation, resulting in increased carcinogenesis. We thus hypothesized that cellular distribution of upregulated ROS1 in OSCC may correlate with invasiveness. We found that ROS1 can localize to mitochondria in the highly invasive OSCC and identified a mitochondria-targeting signal sequence in ROS1. We also demonstrated that ROS1 targeting to mitochondria is required for mitochondrial fission phenotype in the highly invasive OSCC cells. OSCC cells expressing high levels of ROS1 consumed more oxygen and had increased levels of cellular ATP levels. Our results also revealed that ROS1 regulates mitochondrial biogenesis and cellular metabolic plasticity. Together, these findings demonstrate that ROS1 targeting to mitochondria enhances OSCC invasion through regulating mitochondrial morphogenesis and cellular respiratory.

8.
Int J Mol Sci ; 21(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575541

RESUMO

Isoplumbagin (5-hydroxy-3-methyl-1,4-naphthoquinone), a naturally occurring quinone from Lawsonia inermis and Plumbago europaea, has been reported to have anti-inflammatory and antimicrobial activity. Inflammation has long been implicated in cancer progression. In this study, we examined the anticancer effect of chemically synthesized isoplumbagin. Our results revealed that isoplumbagin treatment suppressed cell viability and invasion of highly invasive oral squamous cell carcinoma (OSCC) OC3-IV2 cells, glioblastoma U87 cells, non-small cell lung carcinoma H1299 cells, prostate cancer PC3 cells, and cervical cancer HeLa cells by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Boyden chamber assays. In vivo studies demonstrate the inhibitory effect of 2 mg/kg isoplumbagin on the growth of orthotopic xenograft tumors derived from OSCC cells. Mechanistically, isoplumbagin exerts its cytotoxic effect through acting as a substrate of reduced nicotinamide adenine dinucleotide phosphate [NAD(P)H] dehydrogenase quinone 1 (NQO1) to generate hydroquinone, which reverses mitochondrial fission phenotype, reduces mitochondrial complex IV activity, and thus compromises mitochondrial function. Collectively, this work reveals an anticancer activity of isoplumbagin mainly through modulating mitochondrial dynamics and function.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , NAD(P)H Desidrogenase (Quinona)/metabolismo , Naftoquinonas/administração & dosagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Camundongos , Naftoquinonas/síntese química , Naftoquinonas/química , Naftoquinonas/farmacologia , Células PC-3 , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
BMC Genomics ; 19(Suppl 9): 238, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-30999844

RESUMO

BACKGROUND: With the rapid increase in genome sequencing projects for non-model organisms, numerous genome assemblies are currently in progress or available as drafts, but not made available as satisfactory, usable genomes. Data quality assessment of genome assemblies is gaining importance not only for people who perform the assembly/re-assembly processes, but also for those who attempt to use assemblies as maps in downstream analyses. Recent studies of the quality control, quality evaluation/ assessment of genome assemblies have focused on either quality control of reads before assemblies or evaluation of the assemblies with respect to their contiguity and correctness. However, correctness assessment depends on a reference and is not applicable for de novo assembly projects. Hence, development of methods providing both post-assembly and pre-assembly quality assessment reports for examining the quality/correctness of de novo assemblies and the input reads is worth studying. RESULTS: We present SQUAT, an efficient tool for both pre-assembly and post-assembly quality assessment of de novo genome assemblies. The pre-assembly module of SQUAT computes quality statistics of reads and presents the analysis in a well-designed interface to visualize the distribution of high- and poor-quality reads in a portable HTML report. The post-assembly module of SQUAT provides read mapping analytics in an HTML format. We categorized reads into several groups including uniquely mapped reads, multiply mapped, unmapped reads; for uniquely mapped reads, we further categorized them into perfectly matched, with substitutions, containing clips, and the others. We carefully defined the poorly mapped (PM) reads into several groups to prevent the underestimation of unmapped reads; indeed, a high PM% would be a sign of a poor assembly that requires researchers' attention for further examination or improvements before using the assembly. Finally, we evaluate SQUAT with six datasets, including the genome assemblies for eel, worm, mushroom, and three bacteria. The results show that SQUAT reports provide useful information with details for assessing the quality of assemblies and reads. AVAILABILITY: The SQUAT software with links to both its docker image and the on-line manual is freely available at https://github.com/luke831215/SQUAT .


Assuntos
Confiabilidade dos Dados , Genoma , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Software , Agaricales/genética , Animais , Caenorhabditis elegans/genética , Mapeamento Cromossômico , Electrophorus/genética , Controle de Qualidade
10.
PLoS One ; 13(10): e0205249, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30307971

RESUMO

Exposure to 3,5-dimethylaminophenol (3,5-DMAP), the metabolite of the 3-5-dimethylaniline, was shown to cause high levels of oxidative stress in different cells. The aim of the present work was to observe whether this metabolite can lead to cytotoxicity, oxidative stress, DNA damage and cell cycle changes in non-small cell lung cancer A549 cells. 3,5-DMAP caused a dose-dependent increase in cytotoxicity, generation of superoxide (O2-.), inductions in the enzyme activities orchestrating cellular antioxidant balance, increases in lipid peroxidation as well as DNA damage. However, 3,5-DMAP showed significantly lower cytotoxicity towards human lung fibroblast (HLF) cells. 3,5-DMAP also led to molecular events, like inducing apoptotic markers (ie. p53, Bad, Bax and cytochrome c); decreasing anti-apoptotic proteins (Bcl-2) and alterations in cell cycle. Our findings indicate that the cytotoxicity caused by this particular alkylaniline metabolite led to initiation of caspase 3-mediated apoptosis. Furthermore, 3,5-DMAP attenuated carcinogenic properties like migration capacity of A549 cells and eventually inhibited growth of A549 cells in an in vivo mouse model. Tumor sections showed that 3,5-DMAP down-regulated c-Myc expression but up-regulated p53 and cytochrome c, all of which might result in tumor growth arrest. Co-treatment with N-acetylcysteine provided reductions in cytotoxicity and positively modulated genetic events induced by 3,5-DMAP in A549 cells. In conclusion, our findings demonstrate 3,5-DMAP may be a potential anti-cancer drug in cancer, due to its self redox cycling properties.


Assuntos
Aminofenóis/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Dano ao DNA/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Células A549 , Acetilcisteína/farmacologia , Aminofenóis/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Fibroblastos , Sequestradores de Radicais Livres/farmacologia , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Carcinogenesis ; 38(3): 336-345, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28426879

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP), the common plasticizer used in the production of polyvinyl chloride, can be converted to the more potent metabolite mono-ethylhexyl phthalate (MEHP). Epidemiological studies have shown an association with elevated induction of rat hepatic cancer and reproductive toxicity in response to MEHP exposure. However, the mechanism of genotoxicity and carcinogenicity induced by MEHP treatment remains unclear. As a means to elucidate the mechanisms of action, lethality and mutagenicity in the adenine phosphoribosyltransferase (aprt+/-) gene induced in several CHO cell types by MEHP were assessed. Dose-response relationships were determined in the parental AA8 cell line, its nucleotide repair-deficient UV5 and base repair-deficient EM9 subclones, and also in AS52 cells harboring the bacterial guanine-hypoxanthine phosphoribosyltransferase (gpt) gene and its derived AS52-XPD-knockdown and AS52-PARP-1-knockdown cells. Treatment of AS52 with MEHP led to intracellular production of reactive oxygen species (ROS) and DNA strand breaks in a dose-dependent manner. Separately, mutations in the gpt gene of AS52 cells were characterized and found to be dominated by G:C to A:T and A:T to G:C transitions. Independent AS52-mutant cell (ASMC) clones were collected for the sequential in vivo xenograft tumorigenic studies, 4 of total 20 clones had aggressive tumor growth. Moreover, microarray analysis indicated miR-let-7a and miR-125b downregulated in ASMC, which might raise oncogenic MYC and RAS level and activate ErbB pathway. Comparative evaluation of the results indicates that the principal mechanism of this mutagenic action is probably to be through generation of ROS, causing base excision damage resulting in carcinogenicity.


Assuntos
Dietilexilftalato/análogos & derivados , Dietilexilftalato/metabolismo , Mutagênese/genética , Poli(ADP-Ribose) Polimerase-1/genética , Animais , Células CHO , Cricetinae , Cricetulus , Dano ao DNA/efeitos dos fármacos , Humanos , Mutagênese/efeitos dos fármacos , Testes de Mutagenicidade , Mutação/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
12.
Biochim Biophys Acta Gene Regul Mech ; 1860(2): 270-281, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28039048

RESUMO

As mesoderm-derived cell lineage commits to myogenesis, a spectrum of signaling molecules, including insulin growth factor (IGF), activate signaling pathways and ultimately instruct chromatin remodeling and the transcription of myogenic genes. MyoD is a key transcription factor during myogenesis. In this study, we have identified and characterized a novel myogenic regulator, SH2B1. Knocking down SH2B1 delays global chromatin condensation and decreases the formation of myotubes. SH2B1 interacts with histone H1 and is required for the removal of histone H1 from active transcription sites, allowing for the expressions of myogenic genes, IGF2 and MYOG. Chromatin immunoprecipitation assays suggest the requirement of SH2B1 for the induction of histone H3 lysine 4 trimethylation as well as the reduction of histone H3 lysine 9 trimethylation at the promoters and/or enhancers of IGF2 and MYOG genes during myogenesis. Furthermore, SH2B1 is required for the transcriptional activity of MyoD and MyoD occupancy at the enhancer/promoter regions of IGF2 and MYOG during myogenesis. Together, this study demonstrates that SH2B1 fine-tunes global-local chromatin states, expressions of myogenic genes and ultimately promotes myogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cromatina/metabolismo , Desenvolvimento Muscular/genética , Proteína MyoD/metabolismo , Linhagem Celular , Montagem e Desmontagem da Cromatina/genética , Imunoprecipitação da Cromatina/métodos , Elementos Facilitadores Genéticos/genética , Células HEK293 , Histonas/metabolismo , Humanos , Fator de Crescimento Insulin-Like II/metabolismo , Metilação , Miogenina/metabolismo , Regiões Promotoras Genéticas/genética , Ativação Transcricional/genética
13.
Am J Chin Med ; 44(2): 355-76, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27080945

RESUMO

Epidemiological studies show increased particulate matter (PM[Formula: see text]) particles in ambient air are correlated with increased myocardial infarctions. Given the close association of capillaries and alveoli, the dysfunction is caused when inhaled PM[Formula: see text] particles come in close proximity to capillary endothelial cells. We previously suggested that the inhalation of PM[Formula: see text] diesel exhaust particles (DEP) induces oxidative stress and upregulates the Nrf2/HO-1 pathway, inducing vascular permeability factor VEGFA secretion, which results in cell-cell adherens junction disruption and PM[Formula: see text] transmigratation into circulation. Here, we minimized the level that PM[Formula: see text] traveled in the bloodstream by pre-supplementing with a traditional Chinese medicine (TCM) Ganoderma tsugae DMSO extract (GTDE) prior to PM[Formula: see text] exposure. Our results show that PM[Formula: see text] caused alterations in enzyme activities and cellular anti-oxidant balance. We found decreased glutathione levels, a reduced cellular redox ratio, increased ROS generation and cytotoxicity in the cellular fractions. The oxidative stress caused DNA damage and apoptosis, likely causing downstream molecular events that trigger vasculature permeabilization and, eventually, cardiovascular disorders. Our results show long-term GTDE treatment increased endogenous glutathione level, while PM[Formula: see text]-reduced glutathione levels and the cellular redox ratio. GTDE was protective against the genotoxic and apoptotic effects initiated by PM[Formula: see text] oxidative stress. Vascular permeability revealed that PM[Formula: see text] only accumulated on the surface of cells after GTDE treatment; no penetration was detected. After two weeks of GTDE treatment, VEGFA secretion was significantly reduced in human umbilical vein endothelial cells (HUVEC) and endothelial cell migration was blocked. Our results suggest GTDE prevents PM[Formula: see text] transmigration into the bloodstream, and the resultant dysfunction, by inhibiting oxidative stress production and endothelial permeability.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Ganoderma/química , Material Particulado/efeitos adversos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Glutationa/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Junções Intercelulares/metabolismo , Infarto do Miocárdio/induzido quimicamente , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/metabolismo , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
BMC Genomics ; 16 Suppl 12: S9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26678408

RESUMO

BACKGROUND: Recent progress in next-generation sequencing technology has afforded several improvements such as ultra-high throughput at low cost, very high read quality, and substantially increased sequencing depth. State-of-the-art high-throughput sequencers, such as the Illumina MiSeq system, can generate ~15 Gbp sequencing data per run, with >80% bases above Q30 and a sequencing depth of up to several 1000x for small genomes. Illumina HiSeq 2500 is capable of generating up to 1 Tbp per run, with >80% bases above Q30 and often >100x sequencing depth for large genomes. To speed up otherwise time-consuming genome assembly and/or to obtain a skeleton of the assembly quickly for scaffolding or progressive assembly, methods for noise removal and reduction of redundancy in the original data, with almost equal or better assembly results, are worth studying. RESULTS: We developed two subset selection methods for single-end reads and a method for paired-end reads based on base quality scores and other read analytic tools using the MapReduce framework. We proposed two strategies to select reads: MinimalQ and ProductQ. MinimalQ selects reads with minimal base-quality above a threshold. ProductQ selects reads with probability of no incorrect base above a threshold. In the single-end experiments, we used Escherichia coli and Bacillus cereus datasets of MiSeq, Velvet assembler for genome assembly, and GAGE benchmark tools for result evaluation. In the paired-end experiments, we used the giant grouper (Epinephelus lanceolatus) dataset of HiSeq, ALLPATHS-LG genome assembler, and QUAST quality assessment tool for comparing genome assemblies of the original set and the subset. The results show that subset selection not only can speed up the genome assembly but also can produce substantially longer scaffolds. AVAILABILITY: The software is freely available at https://github.com/moneycat/QReadSelector.


Assuntos
Biologia Computacional/métodos , Mapeamento de Sequências Contíguas/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Animais , Bacillus cereus/genética , Escherichia coli/genética , Tamanho do Genoma , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Perciformes/genética , Análise de Sequência de DNA/instrumentação , Software
15.
Commun Integr Biol ; 8(4): e1044189, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26479731

RESUMO

Morphogenesis during development is fundamental to the differentiation of several cell types. As neurite outgrowth marks neuritogenesis, formation of filopodia precede the formation of dendrites and axons. While the structure of filopodia is well-known, the initiation of filopodia during neurite outgrowth is not clear. SH2B1 is known to promote neurite outgrowth of PC12 cells, hippocampal and cortical neurons. As a signaling adaptor protein, SH2B1 interacts with several neurotrophin receptors, and regulates signaling as well as gene expression. Our recent findings suggest that SH2B1 can be recruited to the plasma membrane and F-actin fractions by IRSp53. IRSp53 bends plasma membrane and facilitates actin bundling to set the stage for filopodium formation. We further demonstrate that SH2B1-IRSp53 complexes enhance the formation of filopodia, dendrites and dendritic branches of hippocampal and cortical neurons. While the molecular mechanism underlying filopodium initiation is not clear, we propose that SH2B1-neurotrophin interacting sites may mark the putative sites of filopodium initiation.

16.
PLoS One ; 10(7): e0131911, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26148005

RESUMO

Exposure to diesel exhaust particles (DEP) is associated with pulmonary and cardiovascular diseases. Previous studies using in vitro endothelial tubes as a simplified model of capillaries have found that DEP-induced ROS increase vascular permeability with rearrangement or internalization of adherens junctional VE-cadherin away from the plasma membrane. This allows DEPs to penetrate into the cell and capillary lumen. In addition, pro-inflammatory cytokines are up-regulated and mediate vascular permeability in response to DEP. However, the mechanisms through which these DEP-induced pro-inflammatory cytokines increase vascular permeability remain unknown. Hence, we examined the ability of DEP to induce permeability of human umbilical vein endothelial cell tube cells to investigate these mechanisms. Furthermore, supplementation with NAC reduces ROS production following exposure to DEP. HUVEC tube cells contributed to a pro-inflammatory response to DEP-induced intracellular ROS generation. Endothelial oxidative stress induced the release of TNF-α and IL-6 from tube cells, subsequently stimulating the secretion of VEGF-A independent of HO-1. Our data suggests that DEP-induced intracellular ROS and release of the pro-inflammatory cytokines TNF- α and IL-6, which would contribute to VEGF-A secretion and disrupt cell-cell borders and increase vasculature permeability. Addition of NAC suppresses DEP-induced ROS efficiently and reduces subsequent damages by increasing endogenous glutathione.


Assuntos
Cisteína/farmacologia , Citocinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inflamação/metabolismo , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Emissões de Veículos/toxicidade , Junções Aderentes/efeitos dos fármacos , Junções Aderentes/metabolismo , Antígenos CD/metabolismo , Caderinas/metabolismo , Capilares/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Células Cultivadas , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/induzido quimicamente , Interleucina-6/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
J Biol Chem ; 290(10): 6010-21, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25586189

RESUMO

SH2B1 is an adaptor protein known to enhance neurite outgrowth. In this study, we provide evidence suggesting that the SH2B1 level is increased during in vitro culture of hippocampal neurons, and the ß isoform (SH2B1ß) is the predominant isoform. The fact that formation of filopodia is prerequisite for neurite initiation suggests that SH2B1 may regulate filopodium formation and thus neurite initiation. To investigate whether SH2B1 may regulate filopodium formation, the effect of SH2B1 and a membrane and actin regulator, IRSp53 (insulin receptor tyrosine kinase substrate p53), is investigated. Overexpressing both SH2B1ß and IRSp53 significantly enhances filopodium formation, neurite outgrowth, and branching. Both in vivo and in vitro data show that SH2B1 interacts with IRSp53 in hippocampal neurons. This interaction depends on the N-terminal proline-rich domains of SH2B1. In addition, SH2B1 and IRSp53 co-localize at the plasma membrane, and their levels increase in the Triton X-100-insoluble fraction of developing neurons. These findings suggest that SH2B1-IRSp53 complexes promote the formation of filopodia, neurite initiation, and neuronal branching.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Proteínas de Transporte/biossíntese , Diferenciação Celular/genética , Dendritos/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Transporte/metabolismo , Proliferação de Células , Regulação da Expressão Gênica no Desenvolvimento , Hipocampo/crescimento & desenvolvimento , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas do Tecido Nervoso/metabolismo , Neuritos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Transporte Proteico , Pseudópodes/genética , Pseudópodes/metabolismo , Ratos
18.
Cardiovasc Toxicol ; 15(4): 345-54, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25488805

RESUMO

Previous studies suggest a direct correlation between exposure to diesel exhaust particles (DEP) and the onset of vascular permeability, presumably through the disruption of the adherens junctions. This would lead to deleterious effects on vasculature, such as acute myocardial infarction and atherosclerosis. Although the mechanism remains unclear, we demonstrate DEP-induced mitochondrial reactive oxygen species generation, which may be a central cause of the above vascular disorders. In vitro capillary-like HUVEC tube cells are used in this study and show that acute DEP exposure stimulates ATP depletion, followed by depolarization of their actin cytoskeleton, which sequentially inhibits PI3K/Akt activity and induces endothelial apoptosis. These events are accompanied by induction of p53/Mdm2 feedback regulation at 10 µg/mL DEP and produce 20 % cell apoptosis. Nevertheless, 100 µg/mL DEP augments tube cell apoptosis up to 70 % but disrupts the p53 negative regulator Mdm2. Addition of N-acetylcysteine provides substantial protection against the cytotoxic effects of DEP. In summary, exposure to a low dose of DEP actin triggers cytoskeleton depolarization, reduces PI3K/Akt activity, and induces a p53/Mdm2 feedback loop, and a high dose causes apoptosis by depleting Mdm2.


Assuntos
Apoptose/efeitos dos fármacos , Capilares/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/toxicidade , Emissões de Veículos/toxicidade , Trifosfato de Adenosina/metabolismo , Antioxidantes/farmacologia , Capilares/metabolismo , Capilares/patologia , Células Cultivadas , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxidos/metabolismo , Proteína Supressora de Tumor p53/metabolismo
19.
PLoS One ; 9(6): e98146, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24897343

RESUMO

BACKGROUND: Explosive growth of next-generation sequencing data has resulted in ultra-large-scale data sets and ensuing computational problems. Cloud computing provides an on-demand and scalable environment for large-scale data analysis. Using a MapReduce framework, data and workload can be distributed via a network to computers in the cloud to substantially reduce computational latency. Hadoop/MapReduce has been successfully adopted in bioinformatics for genome assembly, mapping reads to genomes, and finding single nucleotide polymorphisms. Major cloud providers offer Hadoop cloud services to their users. However, it remains technically challenging to deploy a Hadoop cloud for those who prefer to run MapReduce programs in a cluster without built-in Hadoop/MapReduce. RESULTS: We present CloudDOE, a platform-independent software package implemented in Java. CloudDOE encapsulates technical details behind a user-friendly graphical interface, thus liberating scientists from having to perform complicated operational procedures. Users are guided through the user interface to deploy a Hadoop cloud within in-house computing environments and to run applications specifically targeted for bioinformatics, including CloudBurst, CloudBrush, and CloudRS. One may also use CloudDOE on top of a public cloud. CloudDOE consists of three wizards, i.e., Deploy, Operate, and Extend wizards. Deploy wizard is designed to aid the system administrator to deploy a Hadoop cloud. It installs Java runtime environment version 1.6 and Hadoop version 0.20.203, and initiates the service automatically. Operate wizard allows the user to run a MapReduce application on the dashboard list. To extend the dashboard list, the administrator may install a new MapReduce application using Extend wizard. CONCLUSIONS: CloudDOE is a user-friendly tool for deploying a Hadoop cloud. Its smart wizards substantially reduce the complexity and costs of deployment, execution, enhancement, and management. Interested users may collaborate to improve the source code of CloudDOE to further incorporate more MapReduce bioinformatics tools into CloudDOE and support next-generation big data open source tools, e.g., Hadoop BigTop and Spark. AVAILABILITY: CloudDOE is distributed under Apache License 2.0 and is freely available at http://clouddoe.iis.sinica.edu.tw/.


Assuntos
Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Software , Algoritmos
20.
J Signal Transduct ; 2014: 962962, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24829797

RESUMO

Fibroblast growth factor-1 (FGF-1) is a well characterized growth factor among the 22 members of the FGF superfamily in humans. It binds to all the four known FGF receptors and regulates a plethora of functions including cell growth, proliferation, migration, differentiation, and survival in different cell types. FGF-1 is involved in the regulation of diverse physiological processes such as development, angiogenesis, wound healing, adipogenesis, and neurogenesis. Deregulation of FGF-1 signaling is not only implicated in tumorigenesis but also is associated with tumor invasion and metastasis. Given the biomedical significance of FGFs and the fact that individual FGFs have different roles in diverse physiological processes, the analysis of signaling pathways induced by the binding of specific FGFs to their cognate receptors demands more focused efforts. Currently, there are no resources in the public domain that facilitate the analysis of signaling pathways induced by individual FGFs in the FGF/FGFR signaling system. Towards this, we have developed a resource of signaling reactions triggered by FGF-1/FGFR system in various cell types/tissues. The pathway data and the reaction map are made available for download in different community standard data exchange formats through NetPath and NetSlim signaling pathway resources.

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