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1.
PeerJ ; 12: e17173, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560460

RESUMO

Background: Table tennis is an asymmetric sport involving the powerful forward swing of the upper limbs depends on the solid support of the lower limbs. The foot drive really affects the weight balance and stroke accuracy even though the distance and momentum of the lower limb displacement are limited within a limited range. Given that previous research on table tennis has typically focused on the footwork and stroke performance of professional players, the study aimed to investigate the daily static and dynamic plantar load distribution as well as the centers of gravity balance and rearfoot posture among Taiwanese college elite table tennis players. Methods: This is a cross-sectional study of 70 elite male table tennis players (age: 20.0 ± 0.9 years; height: 173.4 ± 5.1 cm, weight: 67.6 ± 5.3 kg, experience: 10.0 ± 1.6 years) and 77 amateur table tennis players of the same gender (age: 20.1 ± 0.8 years, height: 167.4 ± 4.4 cm, weight: 64.3 ± 4.0 kg, experience: 4.4 ± 1.2 years) from Taiwanese universities. The JC Mat optical plantar pressure analyzer was applied to determine the plantar load distribution along with arch index (AI) and centers of gravity balance. Assessment of rearfoot postural alignment was mainly used to contrast the performance of the centers of gravity balance. Results: The static arch indices of both feet in the elite group were symmetrical and considered normal arches (AI: 0.22 ± 0.07) during their non-training and non-competition daily lives. Their static plantar loads were symmetrically concentrated on the bipedal lateral metatarsals (P < 0.05) as well as shifted to the medial and lateral heels (P < 0.05) and the lateral metatarsals (P < 0.05) during the walking midstance phase. Additionally, the plantar loads were mainly applied to the bipedal medial (P < 0.01) and lateral heels (P < 0.05) during the transitional changes between both states. Elite athletes had symmetrical and evenly distributed centers of gravity on both feet (left: 50.03 ± 4.47%; right: 49.97 ± 4.47%) when standing statically, along with symmetrical rearfoot angles and neutral position of the subtalar joint (left: 2.73 ± 2.30°; right: 2.70 ± 2.32°) even though they were statistically lower than those of the amateur athletes (P < 0.05). Conclusions: The daily static and dynamic foot patterns of Taiwanese college elite table tennis players were characterized by plantar load distribution on the lateral metatarsals and the entire calcaneus along with balanced centers of gravity and normal rearfoot posture. This foot and posture layout outlines the excellent athletic performance of the foot and ankle in professional athletes. Portions of this text were previously published as part of a preprint (https://doi.org/10.21203/rs.3.rs-2993403/v1).


Assuntos
Acidente Vascular Cerebral , Tênis , Humanos , Masculino , Adulto Jovem , Adulto , Estudos Transversais , Universidades , Postura
2.
bioRxiv ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38328123

RESUMO

With the increasing prevalence of antimicrobial-resistant bacterial infections, there is great interest in using lytic bacteriophages (phages) to treat such infections. However, the factors that govern bacteriophage pharmacokinetics in vivo remain poorly understood. Here, we have examined the contribution of neutrophils, the most abundant phagocytes in the body, to the pharmacokinetics of intravenously administered bacteriophage in uninfected mice. A single dose of LPS-5, an antipseudomonal bacteriophage recently used in human clinical trials, was administered intravenously to both wild-type BALB/c and neutropenic ICR mice. Phage concentrations were assessed in peripheral blood and spleen at 0.5, 1, 2, 4, 8, 12, and 24 hours after administration by plaque assay and qPCR. We observed that the phage clearance is only minimally affected by neutropenia. Indeed, the half-life of phages in blood in BALB/c and ICR mice is 3.45 and 3.66 hours, respectively. These data suggest that neutrophil-mediated phagocytosis is not a major determinant of phage clearance. Conversely, we observed a substantial discrepancy in circulating phage levels over time when measured by qPCR versus plaque assay, suggesting that substantial functional inactivation of circulating phages occurs over time. These data indicate that circulating factors, but not neutrophils, inactivate intravenously administered phages.

3.
Am J Cancer Res ; 13(10): 4721-4733, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970357

RESUMO

The alkaline intracellular environment of cancer cells is critical for cell proliferation and controlled by various plasma membrane transporters including Na+/H+ exchangers (NHEs). NHEs can also mediate cell behavior by regulating signaling transduction. In this study, we investigated the role of NHE7 in cancer stem cell (CSC) activity in non-small cell lung cancer (NSCLC) cells and the potential therapeutic implications of targeting NHE7 and the associated immune checkpoint molecule PD-L1. By analyzing the database from The Cancer Genome Atlas, we found a positive correlation between SLC9A7 mRNA levels (the gene encoding NHE7) and poor overall survival in lung adenocarcinoma patients. Using 5-(N-ethyl-N-isopropyl)-Amiloride (EIPA) to inhibit NHE7 activity, we observed disrupted cell cycle progression and suppressed NSCLC cell proliferation without inducing apoptosis. Furthermore, EIPA demonstrated a suppressive effect on CSC activity, evidenced by decreased tumorsphere numbers and inhibition of CSC markers such as ALDH1A2, ABCG2, CD44, and CD133. Flow cytometric analysis revealed that EIPA treatment or NHE7 knockdown in NSCLC cells led to downregulated PD-L1 expression, associated with inhibited STAT3 activity. Interestingly, EIPA's CSC-targeting activity was preferentially observed in NSCLC cells overexpressing BMI1, while increased PD-L1 expression was detected in BMI1-overexpressing NSCLC cells. Our findings suggest that targeting NHE7 with inhibitors like EIPA may have therapeutic potential in NSCLC treatment by disrupting cell cycle progression and suppressing CSC activity. The observed increase in PD-L1 expression in BMI1-overexpressing NSCLC cells upon EIPA treatment highlights the potential benefit of combining NHE7 inhibitors with anti-PD-L1 agents as a promising new therapeutic strategy for NSCLC.

4.
Langmuir ; 37(26): 8037-8044, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34160231

RESUMO

Microorganisms easily adhere to the surface of substrates and further form biofilms, which present problems in various fields. Therefore, the development of surfaces with antimicrobial adhesion or viability is a promising approach. In this study, we were committed to develop a rapid sterilizing coating. First, polyester fibers were immersed into a mixing solution of dopamine (PDA) and polyethyleneimine (PEI) for forming the co-deposition of PDA and PEI coatings. After this, the co-deposition of PDA and PEI coatings was immersed in a solution of household bleach for chlorination. We found that the nitrogens of PDA and PEI could be chlorinated repeatedly and that the oxidative chlorine content increased with the increasing PEI concentration upon co-deposition. Next, the efficacy of the co-deposition of chlorinated PDA and PEI coatings in eliminating Staphylococcus aureus and Escherichia coli was investigated. We found that the antibacterial ability of the coatings increased with increasing PEI content. In addition, the chlorinated co-deposition coatings had significantly improved antibacterial properties compared to the unchlorinated ones. The chlorinated co-deposition coatings inactivated >99.99% of S. aureus and >99.9% of E. coli after contact of less than 10 min. Therefore, chlorination of a PDA/PEI co-deposition surface is a feasible method for use in antibacterial coatings.


Assuntos
Polietilenoimina , Staphylococcus aureus , Aminas , Escherichia coli , Indóis , Polímeros
5.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33542097

RESUMO

The chimeric transcription factor E2A-PBX1, containing the N-terminal activation domains of E2A fused to the C-terminal DNA-binding domain of PBX1, results in 5% of pediatric acute lymphoblastic leukemias (ALL). We recently have reported a mechanism for RUNX1-dependent recruitment of E2A-PBX1 to chromatin in pre-B leukemic cells; but the subsequent E2A-PBX1 functions through various coactivators and the general transcriptional machinery remain unclear. The Mediator complex plays a critical role in cell-specific gene activation by serving as a key coactivator for gene-specific transcription factors that facilitates their function through the RNA polymerase II transcriptional machinery, but whether Mediator contributes to aberrant expression of E2A-PBX1 target genes remains largely unexplored. Here we show that Mediator interacts directly with E2A-PBX1 through an interaction of the MED1 subunit with an E2A activation domain. Results of MED1 depletion by CRISPR/Cas9 further indicate that MED1 is specifically required for E2A-PBX1-dependent gene activation and leukemic cell growth. Integrated transcriptome and cistrome analyses identify pre-B cell receptor and cell cycle regulatory genes as direct cotargets of MED1 and E2A-PBX1. Notably, complementary biochemical analyses also demonstrate that recruitment of E2A-PBX1 to a target DNA template involves a direct interaction with DNA-bound RUNX1 that can be further stabilized by EBF1. These findings suggest that E2A-PBX1 interactions with RUNX1 and MED1/Mediator are of functional importance for both gene-specific transcriptional activation and maintenance of E2A-PBX1-driven leukemia. The MED1 dependency for E2A-PBX1-mediated gene activation and leukemogenesis may provide a potential therapeutic opportunity by targeting MED1 in E2A-PBX1+ pre-B leukemia.


Assuntos
Carcinogênese/genética , Proteínas de Homeodomínio/metabolismo , Leucemia/genética , Leucemia/patologia , Subunidade 1 do Complexo Mediador/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Transcrição Gênica , Linfócitos B/patologia , Carcinogênese/patologia , Pontos de Checagem do Ciclo Celular , Proliferação de Células/genética , Sobrevivência Celular , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , DNA de Neoplasias/metabolismo , Regulação para Baixo/genética , Regulação Leucêmica da Expressão Gênica , Genes Neoplásicos , Humanos , Ligação Proteica , Estabilidade Proteica
6.
Blood ; 136(1): 11-23, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32276273

RESUMO

E2A, a basic helix-loop-helix transcription factor, plays a crucial role in determining tissue-specific cell fate, including differentiation of B-cell lineages. In 5% of childhood acute lymphoblastic leukemia (ALL), the t(1,19) chromosomal translocation specifically targets the E2A gene and produces an oncogenic E2A-PBX1 fusion protein. Although previous studies have shown the oncogenic functions of E2A-PBX1 in cell and animal models, the E2A-PBX1-enforced cistrome, the E2A-PBX1 interactome, and related mechanisms underlying leukemogenesis remain unclear. Here, by unbiased genomic profiling approaches, we identify the direct target sites of E2A-PBX1 in t(1,19)-positive pre-B ALL cells and show that, compared with normal E2A, E2A-PBX1 preferentially binds to a subset of gene loci cobound by RUNX1 and gene-activating machineries (p300, MED1, and H3K27 acetylation). Using biochemical analyses, we further document a direct interaction of E2A-PBX1, through a region spanning the PBX1 homeodomain, with RUNX1. Our results also show that E2A-PBX1 binding to gene enhancers is dependent on the RUNX1 interaction but not the DNA-binding activity harbored within the PBX1 homeodomain of E2A-PBX1. Transcriptome analyses and cell transformation assays further establish a significant RUNX1 requirement for E2A-PBX1-mediated target gene activation and leukemogenesis. Notably, the RUNX1 locus itself is also directly activated by E2A-PBX1, indicating a multilayered interplay between E2A-PBX1 and RUNX1. Collectively, our study provides the first unbiased profiling of the E2A-PBX1 cistrome in pre-B ALL cells and reveals a previously unappreciated pathway in which E2A-PBX1 acts in concert with RUNX1 to enforce transcriptome alterations for the development of pre-B ALL.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Regulação Leucêmica da Expressão Gênica/genética , Proteínas de Homeodomínio/fisiologia , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/fisiologia , Motivos de Aminoácidos , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Subunidade alfa 2 de Fator de Ligação ao Core/química , Subunidade alfa 2 de Fator de Ligação ao Core/genética , DNA/metabolismo , Elementos Facilitadores Genéticos , Código das Histonas , Proteínas de Homeodomínio/química , Humanos , Complexo Mediador/metabolismo , Proteínas de Fusão Oncogênica/química , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Domínios Proteicos , Mapeamento de Interação de Proteínas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Relação Estrutura-Atividade , Transcriptoma , Fatores de Transcrição de p300-CBP/metabolismo
7.
Elife ; 4: e06283, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26067234

RESUMO

MAF1 represses Pol III-mediated transcription by interfering with TFIIIB and Pol III. Herein, we found that MAF1 knockdown induced CDKN1A transcription and chromatin looping concurrently with Pol III recruitment. Simultaneous knockdown of MAF1 with Pol III or BRF1 (subunit of TFIIIB) diminished the activation and looping effect, which indicates that recruiting Pol III was required for activation of Pol II-mediated transcription and chromatin looping. Chromatin-immunoprecipitation analysis after MAF1 knockdown indicated enhanced binding of Pol III and BRF1, as well as of CFP1, p300, and PCAF, which are factors that mediate active histone marks, along with the binding of TATA binding protein (TBP) and POLR2E to the CDKN1A promoter. Simultaneous knockdown with Pol III abolished these regulatory events. Similar results were obtained for GDF15. Our results reveal a novel mechanism by which MAF1 and Pol III regulate the activity of a protein-coding gene transcribed by Pol II.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Regulação da Expressão Gênica , RNA Polimerase III/metabolismo , Proteínas Repressoras/metabolismo , Linhagem Celular , Imunoprecipitação da Cromatina , DNA/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Repressoras/genética
8.
PLoS One ; 10(2): e0118453, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706888

RESUMO

Oncogenic transformation of normal cells often involves epigenetic alterations, including histone modification and DNA methylation. We conducted whole-genome bisulfite sequencing to determine the DNA methylomes of normal breast, fibroadenoma, invasive ductal carcinomas and MCF7. The emergence, disappearance, expansion and contraction of kilobase-sized hypomethylated regions (HMRs) and the hypomethylation of the megabase-sized partially methylated domains (PMDs) are the major forms of methylation changes observed in breast tumor samples. Hierarchical clustering of HMR revealed tumor-specific hypermethylated clusters and differential methylated enhancers specific to normal or breast cancer cell lines. Joint analysis of gene expression and DNA methylation data of normal breast and breast cancer cells identified differentially methylated and expressed genes associated with breast and/or ovarian cancers in cancer-specific HMR clusters. Furthermore, aberrant patterns of X-chromosome inactivation (XCI) was found in breast cancer cell lines as well as breast tumor samples in the TCGA BRCA (breast invasive carcinoma) dataset. They were characterized with differentially hypermethylated XIST promoter, reduced expression of XIST, and over-expression of hypomethylated X-linked genes. High expressions of these genes were significantly associated with lower survival rates in breast cancer patients. Comprehensive analysis of the normal and breast tumor methylomes suggests selective targeting of DNA methylation changes during breast cancer progression. The weak causal relationship between DNA methylation and gene expression observed in this study is evident of more complex role of DNA methylation in the regulation of gene expression in human epigenetics that deserves further investigation.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA , Genes Neoplásicos , Família Multigênica , Feminino , Humanos , Regiões Promotoras Genéticas , Inativação do Cromossomo X
9.
Mater Sci Eng C Mater Biol Appl ; 37: 60-7, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24582223

RESUMO

In-vitro and in-vivo studies have been conducted on an in-house-developed tetracalcium phosphate (TTCP)/dicalcium phosphate anhydrous (DCPA)/calcium sulfate hemihydrate (CSH)-derived composite cement. Unlike most commercial calcium-based cement pastes, the investigated cement paste can be directly injected into water and harden without dispersion. The viability value of cells incubated with a conditioned medium of cement extraction is >90% that of Al2O3 control and >80% that of blank medium. Histological examination reveals excellent bonding between host bone and cement without interposition of fibrous tissues. At 12 weeks-post implantation, significant remodeling activities are found and a new bone network is developed within the femoral defect. The 26-week samples show that the newly formed bone becomes more mature, while the interface between residual cement and the new bone appears less identifiable. Image analysis indicates that the resorption rate of the present cement is much higher than that of TTCP or TTCP/DCPA-derived cement under similar implantation conditions.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/química , Sulfato de Cálcio/química , Animais , Cimentos Ósseos/uso terapêutico , Cimentos Ósseos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Fraturas do Fêmur/patologia , Fraturas do Fêmur/terapia , Fêmur/patologia , Masculino , Camundongos , Células NIH 3T3 , Porosidade , Coelhos
10.
PLoS One ; 6(7): e22583, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21799907

RESUMO

Actins are the major constituent of the cytoskeleton. In this report we present several lines of evidence that muscle actin genes are transcribed by nuclear isoform of mitochondrial RNA polymerase (spRNAP-IV) whereas the non-muscle actin genes are transcribed by the conventional RNA polymerase II (PolII). We show that mRNA level of muscle actin genes are resistant to PolII inhibitors α-amanitin and triptolide as well as insensitive to knockdown of PolII but not to knockdown of spRNAP-IV, in contrast to non-muscle actin genes in several cell lines. Similar results are obtained from nuclear run-on experiments. Reporter assay using muscle actin or PolII gene promoters also demonstrate the differential sensitivity to PolII inhibitors. Finally, chromatin-immunoprecipitation experiment was used to demonstrate that spRNAP-IV is associated with promoter of muscle actin genes but not with that of non-muscle gene and knockdown of spRNAP-IV depleted this polymerase from muscle actin genes. In summary, these experiments indicate that the two types of actin genes are transcribed by different transcription machinery. We also found that POLRMT gene is transcribed by spRNAP-IV, and actin genes are sensitive to oligomycin, suggesting a transcription coupling between mitochondria and nucleus.


Assuntos
Actinas/genética , Núcleo Celular/enzimologia , RNA Polimerases Dirigidas por DNA/metabolismo , Mitocôndrias/enzimologia , Proteínas Musculares/genética , Transcrição Gênica , Núcleo Celular/genética , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , RNA Polimerases Dirigidas por DNA/deficiência , RNA Polimerases Dirigidas por DNA/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Inibidores Enzimáticos/farmacologia , Técnicas de Silenciamento de Genes , Genes Reporter/genética , Células HeLa , Humanos , Manganês/farmacologia , Mitocôndrias/genética , Regiões Promotoras Genéticas/genética , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/deficiência , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA/biossíntese , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética
11.
BMC Plant Biol ; 11: 3, 2011 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-21208460

RESUMO

BACKGROUND: Phalaenopsis orchids are popular floral crops, and development of new cultivars is economically important to floricultural industries worldwide. Analysis of orchid genes could facilitate orchid improvement. Bacterial artificial chromosome (BAC) end sequences (BESs) can provide the first glimpses into the sequence composition of a novel genome and can yield molecular markers for use in genetic mapping and breeding. RESULTS: We used two BAC libraries (constructed using the BamHI and HindIII restriction enzymes) of Phalaenopsis equestris to generate pair-end sequences from 2,920 BAC clones (71.4% and 28.6% from the BamHI and HindIII libraries, respectively), at a success rate of 95.7%. A total of 5,535 BESs were generated, representing 4.5 Mb, or about 0.3% of the Phalaenopsis genome. The trimmed sequences ranged from 123 to 1,397 base pairs (bp) in size, with an average edited read length of 821 bp. When these BESs were subjected to sequence homology searches, it was found that 641 (11.6%) were predicted to represent protein-encoding regions, whereas 1,272 (23.0%) contained repetitive DNA. Most of the repetitive DNA sequences were gypsy- and copia-like retrotransposons (41.9% and 12.8%, respectively), whereas only 10.8% were DNA transposons. Further, 950 potential simple sequence repeats (SSRs) were discovered. Dinucleotides were the most abundant repeat motifs; AT/TA dimer repeats were the most frequent SSRs, representing 253 (26.6%) of all identified SSRs. Microsynteny analysis revealed that more BESs mapped to the whole-genome sequences of poplar than to those of grape or Arabidopsis, and even fewer mapped to the rice genome. This work will facilitate analysis of the Phalaenopsis genome, and will help clarify similarities and differences in genome composition between orchids and other plant species. CONCLUSION: Using BES analysis, we obtained an overview of the Phalaenopsis genome in terms of gene abundance, the presence of repetitive DNA and SSR markers, and the extent of microsynteny with other plant species. This work provides a basis for future physical mapping of the Phalaenopsis genome and advances our knowledge thereof.


Assuntos
Cromossomos Artificiais Bacterianos/genética , Genoma de Planta/genética , Orchidaceae/genética , Análise de Sequência de DNA/métodos , Sequência Rica em At/genética , Sequência de Bases , Núcleo Celular/genética , Mapeamento Cromossômico , DNA de Cloroplastos/genética , Bases de Dados de Ácidos Nucleicos , Marcadores Genéticos , Repetições Minissatélites/genética , Anotação de Sequência Molecular , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Especificidade da Espécie , Sintenia/genética
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