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1.
Crit Care ; 28(1): 87, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504251

RESUMO

OBJECTIVE: To evaluate the effects of our self-developed endotracheal tube fixation device in mechanically ventilated patients. METHODS: In a dual-centre randomised controlled trial, patients who were expected to require mechanical ventilation for over 48 h were assigned to the observation group (using self-developed device) or the control group (using the traditional device). The primary endpoint was the incidence of endotracheal intubation-related pressure injury (EIRPI). RESULTS: Fifty-one patients in the observation group and 54 patients in the control group were analysed. The incidence of EIRPI was 7.8% in the observation group and 33.3% in the control group (p = 0.001). Lip pressure injury (PI) occurred in 0 versus 14 (25.9%) patients in the observation versus control groups (p < 0.001). Both oral-mucosal and facial PIs were similar between the two groups. CONCLUSIONS: The use of the novel device reduced the incidence of EIRPI, especially lip PI. Trial registration Chinese Clinical Trial Registry ChiCTR2300078132. Registered on 29 November 2023.


Assuntos
Úlcera por Pressão , Humanos , Intubação Intratraqueal/efeitos adversos , Respiração Artificial
2.
BMC Musculoskelet Disord ; 25(1): 400, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773411

RESUMO

OBJECTIVE: Muscle dysfunction caused by repetitive work or strain in the neck region can interfere muscle responses. Muscle dysfunction can be an important factor in causing cervical spondylosis. However, there has been no research on how the biomechanical properties of the upper cervical spine change when the suboccipital muscle group experiences dysfunction. The objective of this study was to investigate the biomechanical evidence for cervical spondylosis by utilizing the finite element (FE) approach, thus and to provide guidance for clinicians performing acupoint therapy. METHODS: By varying the elastic modulus of the suboccipital muscle, the four FE models of C0-C3 motion segments were reconstructed under the conditions of normal muscle function and muscle dysfunction. For the two normal condition FE models, the elastic modulus for suboccipital muscles on both sides of the C0-C3 motion segments was equal and within the normal range In one muscle dysfunction FE model, the elastic modulus on both sides was equal and greater than 37 kPa, which represented muscle hypertonia; in the other, the elastic modulus of the left and right suboccipital muscles was different, indicating muscle imbalance. The biomechanical behavior of the lateral atlantoaxial joint (LAAJ), atlanto-odontoid joint (ADJ), and intervertebral disc (IVD) was analyzed by simulations, which were carried out under the six loadings of flexion, extension, left and right lateral bending, left and right axial rotation. RESULTS: Under flexion, the maximum stress in LAAJ with muscle imbalance was higher than that with normal muscle and hypertonia, while the maximum stress in IVD in the hypertonic model was higher than that in the normal and imbalance models. The maximum stress in ADJ was the largest under extension among all loadings for all models. Muscle imbalance and hypertonia did not cause overstress and stress distribution abnormalities in ADJ. CONCLUSION: Muscle dysfunction increases the stress in LAAJ and in IVD, but it does not affect ADJ.


Assuntos
Vértebras Cervicais , Análise de Elementos Finitos , Humanos , Fenômenos Biomecânicos , Vértebras Cervicais/fisiopatologia , Espondilose/fisiopatologia , Músculos do Pescoço/fisiopatologia , Módulo de Elasticidade , Amplitude de Movimento Articular/fisiologia , Articulação Atlantoaxial/fisiopatologia , Hipertonia Muscular/fisiopatologia , Hipertonia Muscular/etiologia
3.
Opt Express ; 31(23): 38419-38429, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017949

RESUMO

Due to sensitive scaling of the wavelength and the visible-light absorption properties with the device dimension, traditional passive silicon photonic devices with asymmetric waveguide structures cannot achieve polarization control at the visible wavelengths. In this work, a simple and small polarization beam splitter (PBS) for a broad visible-light band, using a tailored silicon nitride (Si3N4) ridge waveguide, is presented, which is based on the distinct optical distribution of two fundamental orthogonal polarized modes in the ridge waveguide. The bending loss for different bending radii and the optical coupling properties of the fundamental modes for different Si3N4 ridge waveguide configurations are analyzed. A PBS composed of a bending ridge waveguide structure and a triple-waveguide directional coupler was fabricated on the Si3N4 thin film. The TM excitation of the device based on a bending ridge waveguide structure shows a polarization extinction ratio (PER) of ≥ 20 dB with 33 nm bandwidth (624-657 nm) and insertion loss (IL) ≤ 1 dB at the through port. The TE excitation of the device, based on a triple-waveguide directional coupler with coupling efficiency distinction between the TE0 and TM0 modes, shows a PER of ≥ 18 dB with 50 nm bandwidth (580-630 nm) and insertion loss (IL) ≤ 1 dB at the cross port. The on-chip Si3N4 PBS device is found to possess the highest known PER at a visible broadband range and small (43 µm) footprint. It should be useful for novel photonic circuit designs and further exploration of Si3N4 PBSs.

4.
BMC Microbiol ; 20(1): 338, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167888

RESUMO

BACKGROUND: Anhydrobiotes, such as the yeast Saccharomyces cerevisiae, are capable of surviving almost total loss of water. Desiccation tolerance requires an interplay of multiple events, including preserving the protein function and membrane integrity, preventing and mitigating oxidative stress, maintaining certain level of energy required for cellular activities in the desiccated state. Many of these crucial processes can be controlled and modulated at the level of organelle morphology and dynamics. However, little is understood about what organelle perturbations manifest in desiccation-sensitive cells as a consequence of drying or how this differs from organelle biology in desiccation-tolerant organisms undergoing anhydrobiosis. RESULTS: In this study, electron and optical microscopy was used to examine the dynamic changes of yeast cells during the desiccation process. Dramatic structural changes were observed during the desiccation process, including the diminishing of vacuoles, decrease of lipid droplets, decrease in mitochondrial cristae and increase of ER membrane, which is likely caused by ER stress and unfolded protein response. The survival rate was significantly decreased in mutants that are defective in lipid droplet biosynthesis, or cells treated with cerulenin, an inhibitor of fatty acid synthesis. CONCLUSION: Our study suggests that the metabolism of lipid droplets and membrane may play an important role in yeast desiccation tolerance by providing cells with energy and possibly metabolic water. Additionally, the decrease in mitochondrial cristae coupled with a decrease in lipid droplets is indicative of a cellular response to reduce the production of reactive oxygen species.


Assuntos
Membrana Celular/metabolismo , Dessecação , Metabolismo dos Lipídeos/fisiologia , Saccharomyces cerevisiae/fisiologia , Aclimatação , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Gotículas Lipídicas/metabolismo , Mitocôndrias/metabolismo , Estresse Fisiológico , Resposta a Proteínas não Dobradas , Vacúolos/metabolismo
5.
Genes Dev ; 26(7): 693-704, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22474261

RESUMO

Argonaute proteins (Ago1-4) are essential components of the microRNA-induced silencing complex and play important roles in both microRNA biogenesis and function. Although Ago2 is the only one with the slicer activity, it is not clear whether the slicer activity is a universally critical determinant for Ago2's function in mammals. Furthermore, functional specificities associated with different Argonautes remain elusive. Here we report that microRNAs are randomly sorted to individual Argonautes in mammals, independent of the slicer activity. When both Ago1 and Ago2, but not either Ago1 or Ago2 alone, are ablated in the skin, the global expression of microRNAs is significantly compromised and it causes severe defects in skin morphogenesis. Surprisingly, Ago3 is able to load microRNAs efficiently in the absence of Ago1 and Ago2, despite a significant loss of global microRNA expression. Quantitative analyses reveal that Ago2 interacts with a majority of microRNAs (60%) in the skin, compared with Ago1 (30%) and Ago3 (<10%). This distribution is highly correlated with the abundance of each Argonaute, as quantified by shotgun proteomics. The quantitative correlation between Argonautes and their associated microRNAs is conserved in human cells. Finally, we measure the absolute expression of Argonaute proteins and determine that their copy number is ~1.4 × 10(5) to 1.7 × 10(5) molecules per cell. Together, our results reveal a quantitative picture for microRNA activity in mammals.


Assuntos
Proteínas Argonautas/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Animais , Proteínas Argonautas/deficiência , Proteínas Argonautas/genética , Proliferação de Células , Fatores de Iniciação em Eucariotos/deficiência , Fatores de Iniciação em Eucariotos/genética , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Knockout , MicroRNAs/metabolismo , Pele/citologia , Pele/metabolismo
6.
J Cell Sci ; 129(6): 1115-27, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26823604

RESUMO

Altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. Although nuclear import rates generally positively correlate with nuclear size, NTF2 levels negatively affect nuclear size, despite the role of NTF2 (also known as NUTF2) in nuclear recycling of the import factor Ran. We show that binding of Ran to NTF2 is required for NTF2 to inhibit nuclear expansion and import of large cargo molecules in Xenopus laevis egg and embryo extracts, consistent with our observation that NTF2 reduces the diameter of the nuclear pore complex (NPC) in a Ran-binding-dependent manner. Furthermore, we demonstrate that ectopic NTF2 expression in Xenopus embryos and mammalian tissue culture cells alters nuclear size. Finally, we show that increases in nuclear size during melanoma progression correlate with reduced NTF2 expression, and increasing NTF2 levels in melanoma cells is sufficient to reduce nuclear size. These results show a conserved capacity for NTF2 to impact on nuclear size, and we propose that NTF2 might be a new cancer biomarker.


Assuntos
Núcleo Celular/química , Núcleo Celular/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Proteínas da Gravidez/metabolismo , Proteína ran de Ligação ao GTP/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Núcleo Celular/genética , Tamanho do Núcleo Celular , Humanos , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas da Gravidez/genética , Ligação Proteica , Xenopus laevis , Proteína ran de Ligação ao GTP/genética
7.
Curr Genet ; 63(2): 229-239, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27387517

RESUMO

The yeast Saccharomyces cerevisiae is capable of responding to various environmental stresses, such as salt stress. Such responses require a complex network and adjustment of the gene expression network. The goal of this study is to further understand the molecular mechanism of salt stress response in yeast, especially the molecular mechanism related to genes BDF1 and HAL2. The Bromodomain Factor 1 (Bdf1p) is a transcriptional regulator, which is part of the basal transcription factor TFIID. Cells lacking Bdf1p are salt sensitive with an abnormal mitochondrial function. We previously reported that the overexpression of HAL2 or deletion of HDA1 lowers the salt sensitivity of bdf1Δ. To better understand the mechanism behind the HAL2-related response to salt stress, we compared three global transcriptional profiles (bdf1Δ vs WT, bdf1Δ + HAL2 vs bdf1Δ, and bdf1Δhda1Δ vs bdf1Δ) in response to salt stress using DNA microarrays. Our results reveal that genes for iron acquisition and cellular and mitochondrial remodeling are induced by HAL2. Overexpression of HAL2 decreases the concentration of nitric oxide. Mitochondrial iron-sulfur cluster (ISC) assembly also decreases in bdf1Δ + HAL2. These changes are similar to the changes of transcriptional profiles induced by iron starvation. Taken together, our data suggest that mitochondrial functions and iron homeostasis play an important role in bdf1Δ-induced salt sensitivity and salt stress response in yeast.


Assuntos
Regulação Fúngica da Expressão Gênica/genética , Ferro/metabolismo , Nucleotidases/genética , Proteínas de Saccharomyces cerevisiae/genética , Tolerância ao Sal/genética , Fatores de Transcrição/genética , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Immunoblotting , Mutação , Nucleotidases/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/genética , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Fatores de Transcrição/metabolismo
8.
BMC Microbiol ; 17(1): 142, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28655353

RESUMO

BACKGROUND: The phytopathogenic Xanthomonas campestris pv.campestris is a gram-negative bacterium and the causal agent of black-rot disease of cruciferous crops. Many gram-negative bacteria possess a family of proteins, called Dsbs, which are involved in disulfide bond formation in certain periplasmic proteins. In our preliminary screening of the virulence to the plants we identified that gene XC_0531 which annotated gene dsbD of Xanthomonas campestris pv. campestris (Xcc) is related to the virulence to the host plants. RESULTS: Here, we found XC_0531 encoded a DsbD like protein. Its deletion is sensitive to DTT and copper, decreased accumulation of free thiols in periplasm. Its deletion also affected heme synthesis, position of Soret band and the production of peak c550. This suggests that XC_0531 is related to c-type cytochromes biogenesis. XC_0531 mutation decreased the utilization of different carbon sources (such as galactose, xylose, maltose, saccharose and glucose), reduced extracellular polysaccharide (EPS) production, decreased extracellular enzyme activities (protease, cellulose and amylase), slowed down growth rate of Xcc and weakened virulence to the plants. These results suggest that these phenotypes caused by XC_0531 mutation is possibly due to deficient biosynthesis of c-type cytochromes in respiration chain and the formation of disulfide bonds. Our work confirmed the function of XC_0531 and provide theory basis for scientists working on molecular mechanisms of cytochrome c biogenesis, pathogenesis of Xcc, development of EPS commercial values and protecting plant from black rot. CONCLUSION: We confirmed the function of gene XC_0531, which encodes a DsbD like protein, a protein correlated with c-type cytochrome biogenesis. This gene is related to the virulence to plants by affecting funtion of cytochromes c and probably disulfide bonds modification of proteins in type II secretion system (T2SS).


Assuntos
Citocromos c/biossíntese , Oxirredutases/genética , Raphanus/microbiologia , Xanthomonas campestris/patogenicidade , Proteínas de Bactérias/genética , Carbono/metabolismo , Dissulfetos/metabolismo , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Mutação , Virulência , Xanthomonas campestris/genética , Xanthomonas campestris/crescimento & desenvolvimento
9.
Proc Natl Acad Sci U S A ; 111(38): E3976-85, 2014 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-25201965

RESUMO

Phosphatidylserine decarboxylase, which is embedded in the inner mitochondrial membrane, synthesizes phosphatidylethanolamine (PE) and, in some cells, synthesizes the majority of this important phospholipid. Normal levels of PE can decline with age in the brain. Here we used yeast and worms to test the hypothesis that low levels of PE alter the homeostasis of the Parkinson disease-associated protein α-synuclein (α-syn). In yeast, low levels of PE in the phosphatidylserine decarboxylase deletion mutant (psd1Δ) cause decreased respiration, endoplasmic reticulum (ER) stress, a defect in the trafficking of the uracil permease, α-syn accumulation and foci, and a slow growth phenotype. Supplemental ethanolamine (ETA), which can be converted to PE via the Kennedy pathway enzymes in the ER, had no effect on respiration, whereas, in contrast, this metabolite partially eliminated ER stress, decreased α-syn foci formation, and restored growth close to that of wild-type cells. In Caenorhabditis elegans, RNAi depletion of phosphatidylserine decarboxylase in dopaminergic neurons expressing α-syn accelerates neurodegeneration, which supplemental ETA rescues. ETA fails to rescue this degeneration in worms that undergo double RNAi depletion of phosphatidylserine decarboxylase (psd-1) and choline/ETA phosphotransferase (cept-1), which encodes the last enzyme in the CDP-ETA Kennedy pathway. This finding suggests that ETA exerts its protective effect by boosting PE through the Kennedy pathway. Overall, a low level of PE causes ER stress, disrupts vesicle trafficking, and causes α-syn to accumulate; such cells likely die from a combination of ER stress and excessive accumulation of α-syn.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Homeostase , Doença de Parkinson/metabolismo , Fosfatidiletanolaminas , Saccharomyces cerevisiae/metabolismo , alfa-Sinucleína/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Carboxiliases/genética , Carboxiliases/metabolismo , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/genética , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Doença de Parkinson/genética , Saccharomyces cerevisiae/genética , alfa-Sinucleína/genética
10.
Development ; 140(9): 1882-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23571213

RESUMO

MicroRNAs (miRNAs) play important roles in differentiation of stem cells. However, the precise dynamics of miRNA induction during stem cell differentiation have not been visualized and molecular mechanisms through which miRNAs execute their function remain unclear. Using high-resolution in situ hybridization together with cell lineage and proliferation markers in mouse skin, we show that miR-203 is transcriptionally activated in the differentiating daughter cells upon the asymmetric cell division of interfollicular progenitor cells. Once induced, miR-203 rapidly promotes the cell cycle exit within 6 hours and abolishes self-renewal of the progenitor cells. With an inducible mouse model, we identify numerous miR-203 in vivo targets that are highly enriched in regulation of cell cycle and cell division, as well as in response to DNA damage. Importantly, co-suppression of individual targets, including p63, Skp2 and Msi2 by miR-203 is required for its function of promoting the cell cycle exit and inhibiting the long-term proliferation. Together, our findings reveal the rapid and widespread impact of miR-203 on the self-renewal program and provide mechanistic insights into the potent role of miR-203 during the epidermal differentiation. These results should also contribute to understanding the role of miR-203 in the development of skin cancer.


Assuntos
Diferenciação Celular , Células Epidérmicas , MicroRNAs/metabolismo , Animais , Divisão Celular Assimétrica , Biomarcadores/metabolismo , Linhagem da Célula , Proliferação de Células , Desenvolvimento Embrionário , Epiderme/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Interferência de RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Quinases Associadas a Fase S/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Tempo , Transativadores/genética , Transativadores/metabolismo , Ativação Transcricional , Transfecção
11.
Curr Microbiol ; 70(5): 671-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25572496

RESUMO

Bromodomain-containing transcription factor, a kind of important regulating protein, can recognize and bind to acetylated histone. The homologous genes, BDF1 and BDF2, in Saccharomyces cerevisiae, respectively, encode a bromodomain-containing transcription factor. Previously study has demonstrated that both BDF1 and BDF2 participate in yeast salt stress response. Bdf1p deletion cells are sensitive to salt stress and this phenotype is suppressed by its homologue BDF2 in a dosage-dependent manner. In this study, we show that the histone deacetylase SIR2 over-expression enhanced dosage-dependent compensation of BDF2. SIR2 over-expression induced a global transcription change, and 1959 gene was down-regulated. We deleted some of the most significant down-regulated genes and did the spot assay. The results revealed that LSP1, an upstream component of endocytosis pathway, and CIN5, a transcription factor that mediates cellular resistance to stresses, can enhance salt resistance of bdf1∆. Further analysis demonstrated that under salt stress the endocytosis is over-activated in bdf1∆ but was recovered in bdf1∆ lsp1∆. To our best knowledge, this is the first report that the transcription factor Bdf1p regulates endocytosis under salt stress via LSP1, a major component of eisosomes that regulate the sites of endocytosis.


Assuntos
Endocitose , Fosfoproteínas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia , Sais/toxicidade , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Teste de Complementação Genética , Fosfoproteínas/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Sirtuína 2/genética , Sirtuína 2/metabolismo , Fatores de Transcrição/genética
12.
Proc Natl Acad Sci U S A ; 109(40): 16119-24, 2012 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-22988096

RESUMO

Parkinson disease (PD) results from the slow, progressive loss of dopaminergic neurons in the substantia nigra. Alterations in α-synuclein (aSyn), such as mutations or multiplications of the gene, are thought to trigger this degeneration. Here, we show that aSyn disrupts mitogen-activated protein kinase (MAPK)-controlled stress signaling in yeast and human cells, which results in inefficient cell protective responses and cell death. aSyn is a substrate of the yeast (and human) polo-like kinase Cdc5 (Plk2), and elevated levels of aSyn prevent Cdc5 from maintaining a normal level of GTP-bound Rho1, which is an essential GTPase that regulates stress signaling. The nine N-terminal amino acids of aSyn are essential for the interaction with polo-like kinases. The results support a unique mechanism of PD pathology.


Assuntos
Degeneração Neural/fisiopatologia , Doença de Parkinson/fisiopatologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/fisiologia , alfa-Sinucleína/metabolismo , Análise de Variância , Western Blotting , Compostos Bicíclicos Heterocíclicos com Pontes , Linhagem Celular Tumoral , Humanos , Microscopia de Fluorescência , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Degeneração Neural/metabolismo , Doença de Parkinson/metabolismo , Tiazolidinas , Leveduras , alfa-Sinucleína/toxicidade , beta-Galactosidase
13.
Carcinogenesis ; 35(2): 469-78, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24085799

RESUMO

Breast cancer is the leading cause of cancer death among females, with tumor metastasis being primarily responsible for breast cancer-associated mortality. Current literatures have shown that microRNAs (miRNAs) are implicated in tumor metastasis. In this study, we found that the expression of miR-720 was significantly downregulated in primary breast cancer, with greater downregulation in metastatic tumors. Statistical analysis of 105 cases of primary human breast cancer demonstrated that decreased expression of miR-720 was correlated with lymph node metastasis. Furthermore, reexpression of miR-720 in breast cancer cells remarkably inhibited cell invasiveness and migration both in vitro and in vivo. Mechanistically, downregulation of TWIST1, a promoter of metastasis that was identified as a direct functional target of miR-720, was attributed to the inhibition of metastasis. Consistent with the reduced TWIST1 levels in breast cancer, reexpression of miR-720 upregulated epithelial markers (E-cadherin and ß-catenin) and downregulated mesenchymal markers (N-cadherin, fibronectin, vimentin and matrix metalloproteinase-2). Expression of miR-720 was inversely associated with TWIST1 in human breast cancer tissues. Knockdown of TWIST1 expression by small interfering RNA exhibited similar effects to reintroduction of miR-720, whereas overexpression of TWIST1 (without the 3'-untranslated region) abrogated miR-720-mediated metastasis inhibition. Collectively, our data indicate that miR-720 is frequently decreased in breast cancer and manifests antimetastatic activity by downregulating TWIST1, presenting a novel mechanism of miRNA-mediated regulation of tumor metastasis.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteínas Nucleares/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Animais , Apoptose , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Proteínas Nucleares/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteína 1 Relacionada a Twist/genética
14.
Microbiology (Reading) ; 160(Pt 10): 2208-2214, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25061043

RESUMO

Saccharomyces cerevisiae Sro7 and Sro77 are homologues of the Drosophila tumour suppressor lethal giant larvae (Lgl), which regulates cell polarity in Drosophila epithelial cells. Here, we showed that double mutation of SRO7/SRO77 was defective in colony growth. The colony of the SRO7/SRO77 double deletion was much smaller than the WT and appeared to be round with a smooth surface, compared with the WT. Analysis using transmission electron microscopy revealed multiple defects of the colony cells, including multiple budding, multiple nuclei, cell lysis and dead cells, suggesting that the double deletion caused defects in cell polarity and cell wall integrity (CWI). Overexpression of RHO1, one of the central regulators of cell polarity and CWI, fully recovered the sro7Δ/sro77Δ phenotype. We further demonstrated that sro7Δ/sro77Δ caused a decrease of the GTP-bound, active Rho1, which in turn caused an upregulation of TOR1. Deletion of TOR1 in sro7Δ/sro77Δ (sro7Δ/sro77Δ/tor1Δ) recovered the cell growth and colony morphology, similar to WT. Our results suggested that the tumour suppressor homologue SRO7/SRO77 regulated cell proliferation and yeast colony development via the Rho1-Tor1 pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Regulação Fúngica da Expressão Gênica , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas rho de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Polaridade Celular , Parede Celular/fisiologia , Parede Celular/ultraestrutura , Microscopia Eletrônica de Transmissão , Mutação , Fosfatidilinositol 3-Quinases/genética , Monoéster Fosfórico Hidrolases , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas rho de Ligação ao GTP/genética
15.
FEMS Yeast Res ; 14(4): 575-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25035869

RESUMO

Bromodomain factor 1 (Bdf1p) is a transcriptional regulator. The absence of Bdf1p causes salt sensitivity with abnormal nucleus and mitochondrial dysfunction. In this study, we reported that the salt sensitivity, mitochondrial dysfunction, and nuclear instability of bdf1Δ mutant were suppressed by HDA1 deletion or MEF1 overexpression. Hda1p overexpression inhibited the relieving effects of low-copy overexpression of MEF1. Further analysis showed that Bdf1p regulated HDA1 transcription positively by binding to its promoter at −201 to +6 bp, whereas Hda1p modulated MEF1 expression negatively by binding to its promoter at −201 to +6 bp. These results suggested that Bdf1p likely regulated MEF1 expression negatively by regulating HDA1 positively. Mitochondrial proteomics analysis showed that the expression levels of six mitochondrial proteins were significantly changed by MEF1 overexpression. Among the six genes, over-expression of PDB1, ILV5, or ATP2 partially recovered the salt stress sensitivity of bdf1Δ. However, none of these mitochondrial proteins could recover mitochondrial respiration indicating that the individual functional proteins could not replace Mef1p activity. It indicated that positive regulation of MEF1 was important in recovering the salt sensitivity of bdf1Δ mutant.


Assuntos
Tolerância a Medicamentos , Proteínas de Ligação ao GTP/biossíntese , Regulação Fúngica da Expressão Gênica , Histona Desacetilases/metabolismo , Proteínas de Saccharomyces cerevisiae/biossíntese , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Sais/toxicidade , Fatores de Transcrição/deficiência , Instabilidade Genômica , Mitocôndrias/metabolismo
16.
Zhongguo Gu Shang ; 37(6): 5715-5, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38910379

RESUMO

OBJECTIVE: To explore dose-effect relationship of biomechanical parameters in treating atlantoaxial joint disorder by slimming manipulation. METHODS: From October 2022 to May 2023, 18 patients with atlantoaxial joint disorders were treated, including 10 males and 8 females;aged from 24 to 27 years old with an average of (25.50±1.10) years old;CT of cervical vertebra showed 16 patients with right side distortion and 2 patients with left side distortion. The mechanical parameters of treatment of atlantoaxial joint disorder by tendon relaxation manipulation were measured by wearing massage manipulation gloves. The magnitude, frequency and mechanical curve of force during tendon relaxation and starting force, pulling force, pulling time and mechanical curve during rehabilitation were quantified, the differences between the affected and contralateral manipulations were compared. RESULTS: The maximum force and frequency of Fengchi(GB20) on the affected side were (19.82±2.02) N and (116.83±14.49) times/min, and opposite side were (13.87±2.19) N and (188.89±16.03) times/min, respectively. There were statistically difference in the maximum force and frequency of both sides (P<0.05). The maximum force and frequency of Quepen (ST12) on the affected side were (14.44±3.27) N and (139.06±28.47) times/min, and those on the opposite side were (9.41±1.38) N and (142.50±28.47) times/min. There was difference in maximum force on both sides (P<0.05). The starting force, turning force and turning time of the affected side were (14.16±5.98) N, (11.56±6.63) N, (0.14±0.03) S, and the contralateral side were (8.94±3.39) N, (8.30±4.64) N, (0.18±0.04) S, respectively. The difference of starting force, turning force and turning time on both sides were statistically significant (P<0.05). CONCLUSION: By applying a light relaxation force on the affected side, the mechanical balance between cervical vertebrae could be restored, and recovery trend of atlantoaxial joint disorder could be strengthened. On this basis, the atlantoaxial odontoid process could be reversed by applying a light rotation force, which reflects the characteristics of high safety of the manipulation.


Assuntos
Articulação Atlantoaxial , Humanos , Masculino , Feminino , Adulto , Articulação Atlantoaxial/fisiopatologia , Tendões/fisiopatologia , Fenômenos Biomecânicos , Adulto Jovem , Artropatias/fisiopatologia , Artropatias/terapia
17.
J Behav Addict ; 13(2): 596-609, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38635338

RESUMO

Background: Although internet gaming disorder (IGD) has been included in the DSM-5 for approximately 10 years, debate remains regarding its existence and classification. Methods: The current research incorporated three approaches. First, implicit association tests were used to examine for potential dissociation between wanting and liking in IGD. Second, brain features in wanting and liking circuits were tested and compared with tobacco use disorder (TUD) when performing a cue-craving task to explore the neural features of wanting and liking. Third, dopaminergic systems were investigated in IGD and TUD using neuromelanin-sensitive MRI. Results: The implicit association test results supported a wanting-liking dissociation in IGD participants. Functional MRI data suggested neural correlates underlying wanting-liking dissociation in IGD and TUD participants, with positive correlations suggesting greater dissociation with increasing addiction severity. Neuromelanin results suggest dopaminergic differences in IGD and TUD relative to healthy control participants. Conclusions: A wanting-liking dissociation in IGD participants suggests gaming motivations in IGD relating to incentive sensitization rather than hedonic responses. The neuromelanin-sensitive MRI results suggest dopaminergic involvement in IGD and TUD. The findings suggest similar brain-behaviour mechanisms for IGD and TUD based on an incentive-sensitization model for addiction, having implications for potential therapeutic strategies and policy-based interventions.


Assuntos
Transtorno de Adição à Internet , Imageamento por Ressonância Magnética , Tabagismo , Humanos , Transtorno de Adição à Internet/fisiopatologia , Transtorno de Adição à Internet/diagnóstico por imagem , Masculino , Adulto Jovem , Adulto , Tabagismo/fisiopatologia , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Motivação/fisiologia , Dopamina/metabolismo , Melaninas/metabolismo , Fissura/fisiologia , Feminino , Adolescente , Jogos de Vídeo
18.
ACS Appl Mater Interfaces ; 16(10): 12647-12660, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38437590

RESUMO

Three new heteroleptic Ru complexes, CYC-B22, CYC-B23C, and CYC-B23T, were prepared as sensitizers for coadsorbent-free, panchromatic, and efficient dye-sensitized solar cells. They are simultaneously functionalized with highly conjugated anchoring and ancillary ligands to explore the electronic and steric effects on their photovoltaic characteristics. The coadsorbent-free device based on CYC-B22 achieved the best power conversion efficiency (PCE) of 8.63% and a panchromatic response extending to 850 nm. The two stereoisomers, CYC-B23C and CYC-B23T coordinated with an unsymmetrical anchoring ligand, display similar absorption properties and the same driving forces for electron injection as well as dye regeneration. Nevertheless, the devices show not only the remarkably distinct PCE (6.64% vs 8.38%) but also discernible stability. The molecular simulation for the two stereoisomers adsorbed on TiO2 clarifies the distinguishable distances (16.9 Å vs 19.0 Å) between the sulfur atoms in the NCS ligands and the surface of the TiO2, dominating the charge recombination dynamics and iodine binding and therefore the PCE and stability of the devices. This study on the steric effects caused by the highly conjugated and unsymmetrical anchoring ligand on the adsorption geometry and photovoltaic performance of the dyes paves a new way for advancing the molecular design of polypyridyl metal complex sensitizers.

19.
EPMA J ; 15(1): 53-66, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463627

RESUMO

Background/aims: The reciprocal promotion of cancer and stroke occurs due to changes in shared risk factors, such as metabolic pathways and molecular targets, creating a "vicious cycle." Cancer plays a direct or indirect role in the pathogenesis of ischemic stroke (IS), along with the reactive medical approach used in the treatment and clinical management of IS patients, resulting in clinical challenges associated with occult cancer in these patients. The lack of reliable and simple tools hinders the effectiveness of the predictive, preventive, and personalized medicine (PPPM/3PM) approach. Therefore, we conducted a multicenter study that focused on multiparametric analysis to facilitate early diagnosis of occult cancer and personalized treatment for stroke associated with cancer. Methods: Admission routine clinical examination indicators of IS patients were retrospectively collated from the electronic medical records. The training dataset comprised 136 IS patients with concurrent cancer, matched at a 1:1 ratio with a control group. The risk of occult cancer in IS patients was assessed through logistic regression and five alternative machine-learning models. Subsequently, select the model with the highest predictive efficacy to create a nomogram, which is a quantitative tool for predicting diagnosis in clinical practice. Internal validation employed a ten-fold cross-validation, while external validation involved 239 IS patients from six centers. Validation encompassed receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and comparison with models from prior research. Results: The ultimate prediction model was based on logistic regression and incorporated the following variables: regions of ischemic lesions, multiple vascular territories, hypertension, D-dimer, fibrinogen (FIB), and hemoglobin (Hb). The area under the ROC curve (AUC) for the nomogram was 0.871 in the training dataset and 0.834 in the external test dataset. Both calibration curves and DCA underscored the nomogram's strong performance. Conclusions: The nomogram enables early occult cancer diagnosis in hospitalized IS patients and helps to accurately identify the cause of IS, while the promotion of IS stratification makes personalized treatment feasible. The online nomogram based on routine clinical examination indicators of IS patients offered a cost-effective platform for secondary care in the framework of PPPM. Supplementary Information: The online version contains supplementary material available at 10.1007/s13167-024-00354-8.

20.
Hum Mol Genet ; 20(17): 3401-14, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21642386

RESUMO

Hydroxyurea (HU) inhibits ribonucleotide reductase (RNR), which catalyzes the rate-limiting synthesis of deoxyribonucleotides for DNA replication. HU is used to treat HIV, sickle-cell anemia and some cancers. We found that, compared with vector control cells, low levels of alpha-synuclein (α-syn) protect S. cerevisiae cells from the growth inhibition and reactive oxygen species (ROS) accumulation induced by HU. Analysis of this effect using different α-syn mutants revealed that the α-syn protein functions in the nucleus and not the cytoplasm to modulate S-phase checkpoint responses: α-syn up-regulates histone acetylation and RNR levels, maintains helicase minichromosome maintenance protein complexes (Mcm2-7) on chromatin and inhibits HU-induced ROS accumulation. Strikingly, when residues 2-10 or 96-140 are deleted, this protective function of α-syn in the nucleus is abolished. Understanding the mechanism by which α-syn protects against HU could expand our knowledge of the normal function of this neuronal protein.


Assuntos
Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Hidroxiureia/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , alfa-Sinucleína/metabolismo , Núcleo Celular/genética , Ribonucleotídeo Redutases/metabolismo , Saccharomyces cerevisiae/genética , alfa-Sinucleína/genética
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