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1.
Zhonghua Gan Zang Bing Za Zhi ; 31(5): 509-517, 2023 May 20.
Artigo em Chinês | MEDLINE | ID: mdl-37365028

RESUMO

Objective: To study the construction of a prognostic model for hepatocellular carcinoma (HCC) based on pyroptosis-related genes (PRGs). Methods: HCC patient datasets were obtained from the Cancer Genome Atlas (TCGA) database, and a prognostic model was constructed by applying univariate Cox and least absolute shrinkages and selection operator (LASSO) regression analysis. According to the median risk score, HCC patients in the TCGA dataset were divided into high-risk and low-risk groups. Kaplan-Meier survival analysis, receiver operating characteristic (ROC) curves, univariate and multivariate Cox analysis, and nomograms were used to evaluate the predictive ability of the prognostic models. Functional enrichment analysis and immune infiltration analysis were performed on differentially expressed genes between the two groups. Finally, two HCC datasets (GSE76427 and GSE54236) from the Gene Expression Omnibus database were used to externally validate the prognostic value of the model. Univariate and multivariate Cox regression analysis or Wilcoxon tests were performed on the data. Results: A total of 366 HCC patients were included after screening the HCC patient dataset obtained from the TCGA database. A prognostic model related to HCC was established using univariate Cox regression analysis, LASSO regression analysis, and seven genes (CASP8, GPX4, GSDME, NLRC4, NLRP6, NOD2, and SCAF11). 366 cases were evenly divided into high-risk and low-risk groups based on the median risk score. Kaplan-Meier survival analysis showed that there were statistically significant differences in the survival time between patients in the high-risk and low-risk groups in the TCGA, GSE76427, and GSE54236 datasets (median overall survival time was 1 149 d vs. 2 131 d, 4.8 years vs. 6.3 years, and 20 months vs. 28 months, with P = 0.000 8, 0.034 0, and 0.0018, respectively). ROC curves showed good survival predictive value in both the TCGA dataset and two externally validated datasets. The areas under the ROC curves of 1, 2, and 3 years were 0.719, 0.65, and 0.657, respectively. Multivariate Cox regression analysis showed that the risk score of the prognostic model was an independent predictor of overall survival time in HCC patients. The risk model score accurately predicted the survival probability of HCC patients according to the established nomogram. Functional enrichment analysis and immune infiltration analysis showed that the immune status of the high-risk group was significantly decreased. Conclusion: The prognostic model constructed in this study based on seven PRGs accurately predicts the prognosis of HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Prognóstico , Piroptose , Neoplasias Hepáticas/genética , Fatores de Risco
2.
J Dent Res ; 102(9): 1058-1068, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37387366

RESUMO

Bone defect (BD) caused by trauma, infection, congenital defects, or neoplasia is a major cause of physical limitation. Distraction osteogenesis (DO) is a highly effective procedure for bone regeneration, while the concrete mechanism remains unknown. In this study, canine DO and BD models of the mandible were established. The results of micro-computed tomography and histological staining revealed that DO led to an increased mineralized volume fraction and robust new bone formation; in contrast, BD demonstrated incomplete bone union. Mesenchymal stem cells (MSCs) from DO and BD calluses were isolated and identified. Compared with BD-MSCs, DO-MSCs were found to have a stronger osteogenic capability. Single-cell RNA sequencing analysis was further performed to comprehensively define cell differences between mandibular DO and BD calluses. Twenty-six clusters of cells representing 6 major cell populations were identified, including paired related homeobox 1-expressing MSCs (PRRX1+MSCs), endothelial cells (ECs), T cells, B cells, neutrophils, and macrophages. Interestingly, 2 subpopulations in PRRX1+MSCs in the DO group were found to express the marker of neural crest cells (NCCs) and were associated with the process of epithelial-mesenchymal transition. The immunofluorescence assay was performed to further corroborate these results in vivo and in vitro, experimentally validating that continuous distraction maintained the PRRX1+MSCs in an embryonic-like state. Finally, we used CRISPR/Cas9 to knock out (KO) PRRX1 in the context of DO, which significantly blunted the capability of jawbone regeneration, resulting in a diminished NCC-like program and reduction of new bone volume. In addition, the ability of osteogenesis, cell migration, and proliferation in cultured PRRX1KO MSCs was inhibited. Taken together, this study provides a novel, comprehensive atlas of the cell fates in the context of DO regeneration, and PRRX1+MSCs act essential roles.


Assuntos
Células-Tronco Mesenquimais , Osteogênese por Distração , Diferenciação Celular , Células Endoteliais , Osteogênese por Distração/métodos , Microtomografia por Raio-X , Osteogênese/genética , Regeneração Óssea , Mandíbula/cirurgia
3.
Artigo em Chinês | MEDLINE | ID: mdl-37006150

RESUMO

Occupational exposure to diacetyl can lead to bronchiolitis obliterans. In this paper, two patients with severe obstructive ventilation disorder who were exposed to diacetyl at a fragrance and flavours factory were analyzed. The clinical manifestations were cough and shortness of breath. One of them showed Mosaic shadows and uneven perfusion in both lungs on CT, while the other was normal. Field investigation found that 4 of the 8 workers in the factory were found to have obstructive ventilation disorder, and 2 had small airway dysfunction. This paper summarizes the diagnostic process of patients in order to improve the understanding of airway dysfunction caused by occupational exposure to diacetyl and promote the development of relevant standards.


Assuntos
Bronquiolite Obliterante , Doenças Profissionais , Exposição Ocupacional , Humanos , Diacetil/efeitos adversos , Doenças Profissionais/diagnóstico , Exposição Ocupacional/efeitos adversos , Pulmão , Bronquiolite Obliterante/induzido quimicamente , Bronquiolite Obliterante/diagnóstico
4.
Eur Rev Med Pharmacol Sci ; 25(3): 1302-1310, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33629300

RESUMO

OBJECTIVE: The systemic immune-inflammation index (SII), an inexpensive and widely available hematologic marker of inflammation, has been linked to tumor progression, metastatic spread, and poor patient prognosis. The objective of this study is to explore the prognostic value of SII in patients with urinary system cancers (USCs). MATERIALS AND METHODS: A comprehensive literature search was conducted by searching the PubMed, EMBASE, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases from inception to May 10, 2020, to identify potential studies that assessed the prognostic role of the SII in USCs. The hazard ratio (HR) with a 95% confidence interval (CI) were used to evaluate the correlation between SII and overall survival (OS), progression-free survival (PFS), and cancer-specific survival (CSS) in USCs patients. RESULTS: A total of 12 studies, including 2,693 USCs patients, were eventually included in the meta-analysis. Elevated SII index was significantly associated with poor OS (HR=1.28, 95% CI: 1.17-1.39, p<0.001), PFS (HR=1.51, 95% CI: 1.25-1.82, p<0.001) and CSS (HR=3.42, 95% CI: 1.49-7.91, p<0.001). Furthermore, subgroup analysis indicated that higher SII than a cutoff value could predict poor OS in renal cell carcinoma (HR=1.23, p<0.001), prostate carcinoma (HR=1.95, p<0.001), bladder carcinoma (HR=5.40, p<0.001), testicular cancer (HR=6.09, p<0.001) and upper tract urothelial carcinoma (HR=2.19, p<0.001). Besides, these associations did not vary significantly by tumor subtypes and stages of USCs, sample sizes, study types, cutoff value defining elevated NLR, treatment methods, and NOS scores. CONCLUSIONS: SII may serve as a useful prognostic indicator in USCs and contribute to prognosis evaluation and treatment strategy formulation. However, more well-designed studies are warranted to verify our findings.


Assuntos
Inflamação/diagnóstico , Neoplasias Renais/diagnóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Humanos , Inflamação/imunologia , Neoplasias Renais/imunologia , Masculino , Prognóstico , Neoplasias da Próstata/imunologia , Neoplasias da Bexiga Urinária/imunologia
6.
Zhonghua Gan Zang Bing Za Zhi ; 28(3): 254-258, 2020 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-32306659

RESUMO

Objective: To investigate the feasibility of cationic antimicrobial peptide cathelicidin-PY(PY) therapy through a mouse model of acute liver failure. Methods: The ability of different concentrations of antimicrobial peptide PY to neutralize endotoxin / lipopolysaccharide (LPS) in vitro was detected by Limulus Amebocyte Lysate (LAL) assay. Cell counting kit-8 (CCK-8) was used to detect the toxic effect of different concentrations of antimicrobial peptide PY on mouse monocyte macrophages (RAW264.7). An in vitro hemolysis experiment was used to evaluate the activity of antimicrobial peptide PY on healthy human erythrocytes. D-galactosamine combined with LPS- induced mouse model of acute liver failure was constructed. The antimicrobial peptide PY effect on survival rate of mouse model was observed. HE staining was used to observe the pathological changes of liver tissue. Immunohistochemistry and Western blotting were used to detect the expression of apoptosis-associated protein caspase-3. Intra-group comparisons were performed using t-test and analysis of variance. χ (2) test was used for the comparison of rates. Results: An in vitro experiment showed that the endotoxin neutralization rate was higher at very low dose (0.01 µmol/L), and exceeded 70% at medium-dose (10-40 µmol/L), and the difference between groups with different concentration was statistically significant (F = 569.22, P < 0.05). Medium-dose antimicrobial peptide PY had strong endotoxin neutralizing effect, low cytotoxicity and hemolytic activity. Moreover, in vivo experiments showed that the degree of liver injury and survival rate of mouse model was significantly improved with the medium-dose of antimicrobial peptide PY. Immunohistochemistry results showed that the expression of caspase-3 in the liver tissue was significantly depleted in the medium-dose group than that of the liver failure group, and the results were consistent with protein immunoblotting testing. Conclusion: Antimicrobial peptide PY possesses a strong ability to neutralize endotoxin and few toxic side effects. A specific dose of antimicrobial peptide PY can attenuate hepatocyte apoptosis and significantly improve the survival rate of animal model, and thus provides a new idea for the liver failure treatment.


Assuntos
Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Falência Hepática Aguda/tratamento farmacológico , Neuropeptídeo Y/uso terapêutico , Animais , Apoptose , Células Cultivadas , Eritrócitos/citologia , Hepatócitos/citologia , Humanos , Lipopolissacarídeos , Camundongos , Células RAW 264.7 , Catelicidinas
7.
Ann R Coll Surg Engl ; 101(6): 415-421, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31155887

RESUMO

INTRODUCTION: We discuss our findings on the retention of the medially displaced residual condyle during the treatment of type III temporomandibular joint ankylosis, as well as the postoperative results observed during follow-up. MATERIALS AND METHODS: Thirty-two patients with type III temporomandibular joint ankylosis that met the inclusion criteria of the study were included as subjects. The morphological integrity of the medially displaced residual condyle was verified in all of the participating patients through the use of cone beam computed tomography. The duration of the ankylosis ranged from 2 to 12 years. The maximum length that patients were able to open their mouths ranged from 6 mm to 14 mm. The surgical treatments used in this report included the separation of bony fusions between the condyle and the glenoid fossa, resection of the ankylosed sites, preservation of the displaced condyles in their medial position and suturing the remains of the disc to its typical position or taking the temporalis myofascial flap instead. The long-term results were evaluated by computed tomography and clinical follow-up examinations. RESULTS: Three-year postoperative follow-up examinations were performed for all of the patients included in this study. No recurrences were observed in the patients who adhered to the postoperative therapeutic advice. Patients had an average maximal mouth opening distance of 34.50 ± 5.75 mm as recorded during the final follow-up examination. CONCLUSIONS: The released medially residual condyle can still function normally in temporomandibular joint movement and without reankylosis after a bone fusion resection. The displaced condyle should thus be preserved instead of being removed during the treatment of type III temporomandibular joint ankylosis.


Assuntos
Anquilose/cirurgia , Artroplastia/métodos , Transtornos da Articulação Temporomandibular/cirurgia , Adolescente , Adulto , Anquilose/diagnóstico por imagem , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Côndilo Mandibular/cirurgia , Articulação Temporomandibular/diagnóstico por imagem , Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
8.
Ann R Coll Surg Engl ; : 1-6, 2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30112938

RESUMO

Introduction We present our experiences using a modified surgical approach from the edge of the tragus for mandibular condyle fractures, to reduce the risk of postoperative complications and visible scars. Materials and methods Thirty-two patients presenting with mandibular condyle fractures were treated through a modified approach on the edge of the tragus. The age of the patients ranged from 6 to 62 years. All mandibular condyle fractures were fixed. The patients were asked to start open-mouth training one week postoperatively, undergoing a cone-beam computed tomography examination and clinical follow-up. Postoperative complications were evaluated after surgery. Results Mouth opening was normal (average 39.5 mm) in all the patients during the operation and the occlusion improved significantly compared with preoperatively. No cases of damaged facial nerves were observed during the final follow-up at six months and postoperative scars were less noticeable. Conclusions The modified surgical approach from the edge of the tragus for mandibular condyle fractures provides a good view of the operative field, reduces the risk of facial nerve damage and produces a less noticeable postoperative scar.

10.
Zhonghua Yi Xue Za Zhi ; 97(7): 535-539, 2017 Feb 21.
Artigo em Chinês | MEDLINE | ID: mdl-28260295

RESUMO

Objective: To estimate the immune response of HepG2/dendritic cell (DC) fusion cells vaccines against HepG2 cells in vitro. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy donors by Ficoll-Hypaque density-gradient centrifugation.Then DC were obtain from PBMCs by culturing in medium containing granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) for 5 days.DC and HepG2 fusion cells were induced by polythyleneglycol (PEG). The fusion cells were examined under fluorescence microscope by labeling DCs and HepG2 with green and red fluorescein, respectively, and then the fusion rates were analyzed by flow cytometry.The capacity of fusion cells to secrete interleukin (IL)-12 and stimulate the proliferation of T lymphocyte was assessed by ELISA and Flow cytometry, respectively.ELISPOT was used to assess the interferon gamma (IFN-γ) produced by cytotoxicity T lymphocyte (CTL), and the specific killing ability of fusion cells induce-CTL targeting HepG2 was estimated. Results: The fusion rate of HepG2/DC was 54.5%, and the fusion cells expressed a higher levels of DC mature marker CD80 and costimulatory molecules CD83, CD86 and MHC-Ⅰ, MHC-Ⅱ molecules HLA-ABC and HLA-DR than those in immature DCs (P<0.01). HepG2/DC showed a greater capacity to secrete high level of IL-12 (P<0.05) and activate proliferation of lymphocytes in vitro, as compared with DCs alone and DCs mix HepG2 (P<0.01). The HepG2/DC -activated CTL generated higher IFN-γ level and had a specific killing ability against HepG2 cells at the effecter/target ratio 30∶1 (31.4%±2.4%) and 100∶1 (57.6%±7.3%) (P<0.01). Conclusions: HepG2/DC fusion cells could efficiently stimulate T lymphocytes to generate specific CTL targeting HepG2 cells.It might be a promising strategy of immunotherapy for HCC.


Assuntos
Vacinas Anticâncer/imunologia , Leucócitos Mononucleares , Comunicação Celular , Fusão Celular , Células Dendríticas , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Células Hep G2 , Humanos , Imunoterapia , Interferon gama , Interleucina-12 , Interleucina-4
11.
Arch Biochem Biophys ; 603: 20-8, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27184165

RESUMO

Cardiac tropnoin I (cTnI) plays a critical role in the regulation of diastolic function, and its low expression may result in cardiac diastolic dysfunction, which is the most common form of cardiovascular disorders in older adults. In this study, cTnI expression levels were determined in mice at various ages and cardiac function was measured and compared between young adult mice (3 and 10 months) and older mice (18 months). The data indicated that the cTnI levels reached a peak high in young adult hearts (3 months), but decreased in older hearts (18 months). Furthermore, the older hearts showed a significant diastolic dysfunction observed by P-V loop and echocardiography measurements. To further define the mechanism underlying the cTnI decrease in aging hearts, we tested DNA methylation and histone acetylation modifications of cTnI gene. We found that acetylation of histone near the promoter region of cTnI gene played an important role in regulation of cTnI expression in the heart at different ages. Our study indicates that epigenetic modification caused cTnI expression decrease is one of the possible causes that result in a reduced cTnI level and diastolic dysfunction in the older hearts.


Assuntos
Envelhecimento , Cardiomiopatias/metabolismo , Diástole , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Troponina I/fisiologia , Animais , Imunoprecipitação da Cromatina , Ecocardiografia , Epigênese Genética , Coração/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas
12.
Opt Express ; 22(21): 26277-84, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25401660

RESUMO

A metal-insulator-metal (MIM) structure which is used to enhance the focusing energy of planar lens is developed in this work. The top of the MIM structure is formed by circularly arranged V-shaped nanoantennas whose double resonance effect makes it possible for light to obtain great phase changes within an ultra-thin area. The middle and bottom of the structure is medium and gold film layer respectively. This structure produces plasmonic coupling between the antenna layer and gold film, thus reducing Ohmic loss and enhancing the effect of plasmonic excitation. When the distance between the antenna layer with a thickness of 30 nm and gold film is 88 nm, and the thickness of gold film is 20 nm, the enhancement of plasmonic coupling reaches to the strongest when the focusing intensity is 1.33 times higher than the lens only. With the advantages of small size, ultra-thin, great phase changes and high-efficient focusing ability, the enhanced plasmonic coupling lens structure can be widely applied in photoetching, and integrated optics.


Assuntos
Lentes , Luz , Nanotecnologia/métodos , Dióxido de Silício/química , Ressonância de Plasmônio de Superfície/métodos , Propriedades de Superfície
13.
Biomed Pharmacother ; 68(4): 455-61, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24721321

RESUMO

Development of a novel angiogenesis inhibitor will be essential for the improvement of therapeutics against cancer. Kallistatin had been recognized as an endogenous angiogenesis inhibitor. Here, we demonstrated kallistatin's strong anti-angiogenesis and anti-metastasis activity stimulated by breast cancer cells (MCF-7) and its mechanism of action in vitro. The anti-angiogenesis effect in vivo was evaluated by chicken chorioallantoic membrane (CAM) neovascularisation. Because of the underlying molecular mechanism of its anti-angiogenesis activity remains poorly understood. In this study, we examined whether the NF-κB signaling pathway was involved in the anti-angiogenesis and anti-metastasis activity of kallistatin. Kallistatin significantly inhibited TNF-α-induced nuclear factor-κB activation in a dose-dependent manner. Addition of kallistatin inhibited TNF-α induced IκBα degradation; phosphorylation of IκBα kinase (IKK), nuclear factor-κB-p65 protein; and nuclear translocation of p65/50. Meanwhile, we investigated the effects of kallistatin on the expression of vascular endothelial growth factor (VEGF) and other angiogenesis-related gene in human umbilical vein endothelial cells (HUVECs). We found that kallistatin decreased the expression of VEGF and some angiogenesis-related genes, which promoted angiogenesis in cancer. Taken together, we suggested that kallistatin would inhibit tumor angiogenesis via inhibition of the NF-κB signaling pathway and finally abrogate NF-κB-dependent gene expression. All the results revealed that kallistatin would have potential as a novel.


Assuntos
Inibidores da Angiogênese/farmacologia , NF-kappa B/antagonistas & inibidores , Neovascularização Patológica/tratamento farmacológico , Serpinas/farmacologia , Inibidores da Angiogênese/administração & dosagem , Animais , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Células MCF-7 , Masculino , Metástase Neoplásica/prevenção & controle , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Ratos , Ratos Sprague-Dawley , Serpinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética
14.
Genet Mol Res ; 13(1): 2107-19, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24615087

RESUMO

Recent evidence suggests that genetic variations in the insulin-like growth factor (IGF)-IGF receptor (IGFR)-IGF binding proteins (IGFBP) axis may impact an individual's susceptibility to lung and esophageal cancer, but individually published results are inconclusive. Our meta-analysis aimed at providing a more precise estimation of these associations. An extensive literature search was conducted for appropriate articles published before May 15th, 2013. This meta-analysis was performed using the STATA 12.0 software. The crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for each study and then pooled using a random effect model. Twelve case-control studies were included with a total of 2686 lung cancer patients, 771 esophageal cancer patients, and 5918 healthy controls. Our meta-analysis indicated that genetic variations in the IGF-IGFR-IGFBP axis may be associated with increased risk of lung and esophageal cancer, especially among Asian populations. Further subgroup analysis by gene type indicated that common polymorphisms in the IGF1/2, IGF-1R, and IGFBP-3/5 genes may be the main determinants for lung cancer risk, while IGF-1, IGF-1R, and IGFBP-1 genetic polymorphisms may increase the risk of esophageal cancer. The current meta-analysis suggests that genetic variations in the IGF-IGFR-IGFBP axis confer susceptibility to lung and esophageal cancer, especially among Asian populations. Common polymorphisms in the IGF-IGFR-IGFBP axis may serve as useful biomarkers for predicting the risk of lung and esophageal cancer.


Assuntos
Neoplasias Esofágicas/genética , Predisposição Genética para Doença , Variação Genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Neoplasias Pulmonares/genética , Receptores de Somatomedina/genética , Somatomedinas/genética , Estudos de Casos e Controles , Estudos de Associação Genética , Humanos , Razão de Chances , Viés de Publicação , Risco
15.
J Cell Biochem ; 113(11): 3559-66, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22740506

RESUMO

Taurine has been shown to have potent anti-oxidant properties under various pathophysiological conditions. We reported previously a cellular dysfunction and mitochondrial damage in cardiac myocytes of methionine sulfoxide reductase A (MsrA) gene knockout mice (MsrA(-/-)). In the present study, we have explored the protective effects of taurine against oxidative stress in the heart of MsrA(-/-) mice with or without taurine treatment. Cardiac cell contractility and Ca(2+) dynamics were measured using cell-based assays and in vivo cardiac function was monitored using high-resolution echocardiography in the tested animals. Our data have shown that MsrA(-/-) mice exhibited a progressive cardiac dysfunction with a significant decrease of ejection fraction (EF) and fraction shortening (FS) at age of 8 months compared to the wild type controls at the same age. However, the dysfunction was corrected in MsrA(-/-) mice treated with taurine supplement in the diet for 5 months. We further investigated the cellular mechanism underlying the protective effect of taurine in the heart. Our data indicated that cardiac myocytes from MsrA(-/-) mice treated with taurine exhibited an improved cell contraction and could tolerate oxidative stress better. Furthermore, taurine treatment reduced significantly the protein oxidation levels in mitochondria of MsrA(-/-) hearts, suggesting an anti-oxidant effect of taurine in cardiac mitochondria. Our study demonstrates that long-term treatment of taurine as a diet supplement is beneficial to a heart that is vulnerable to environmental oxidative stresses.


Assuntos
Antioxidantes/farmacologia , Coração/efeitos dos fármacos , Metionina Sulfóxido Redutases/genética , Mitocôndrias/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Taurina/farmacologia , Animais , Antioxidantes/uso terapêutico , Cálcio/metabolismo , Suplementos Nutricionais , Ecocardiografia , Coração/fisiopatologia , Testes de Função Cardíaca , Peróxido de Hidrogênio/farmacologia , Metionina Sulfóxido Redutases/deficiência , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/metabolismo , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Oxirredução , Estresse Oxidativo , Taurina/uso terapêutico
16.
Biochem Res Int ; 2012: 715197, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22675635

RESUMO

Cardiomyopathies are common cardiac disorders that primarily affect cardiac muscle resulting in cardiac dysfunction and heart failure. Transgenic mouse disease models have been developed to investigate the cellular mechanisms underlying heart failure and sudden cardiac death observed in cardiomyopathy cases and to explore the therapeutic outcomes in experimental animals in vivo. Echocardiography is an essential diagnostic tool for accurate and noninvasive assessment of cardiac structure and function in experimental animals. Our laboratory has been among the first to apply high-frequency research echocardiography on transgenic mice with cardiomyopathies. In this work, we have summarized our and other studies on assessment of systolic and diastolic dysfunction using conventional echocardiography, pulsed Doppler, and tissue Doppler imaging in transgenic mice with various cardiomyopathies. Estimation of embryonic mouse hearts has been performed as well using this high-resolution echocardiography. Some technical considerations in mouse echocardiography have also been discussed.

17.
J Biomed Sci ; 15(6): 789-99, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18563628

RESUMO

The discovery of the naturally occurring cardiac non-function (c) animal strain in Ambystoma mexicanum (axolotl) provides a valuable animal model to study cardiomyocyte differentiation. In homozygous mutant animals (c/c), rhythmic contractions of the embryonic heart are absent due to a lack of organized myofibrils. We have previously cloned a partial sequence of a peptide cDNA (N1) from an anterior-endoderm-conditioned-medium RNA library that had been shown to be able to rescue the mutant phenotype. In the current studies we have fully cloned the N1 full length cDNA sequence from the library. N1 protein has been detected in both adult heart and skeletal muscle but not in any other adult tissues. GFP-tagged expression of the N1 protein has revealed localization of the N1 protein in the endoplasmic reticulum (ER). Results from in situ hybridization experiments have confirmed the dramatic decrease of expression of N1 mRNA in mutant (c/c) embryos indicating that the N1 gene is involved in heart development.


Assuntos
Ambystoma mexicanum/embriologia , Proteínas de Anfíbios/metabolismo , Retículo Endoplasmático/metabolismo , Coração/embriologia , Proteínas Musculares/metabolismo , Ambystoma mexicanum/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Clonagem Molecular , Regulação para Baixo , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Músculo Estriado/metabolismo , Mutação
18.
J Biomed Sci ; 15(5): 605-13, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18357515

RESUMO

Two major troponin I (TnI) genes, fetal TnI (ssTnI) and adult TnI (cTnI), are expressed in the mammalian heart under the control of a developmentally regulated program. In this study, the up-stream domain ( approximately 1,800 bp) of mouse fetal TnI gene has been cloned and characterized. There is a high homology of this region among mouse, rat and human. Analysis of the sequence revealed several putative regulatory domains and binding sites (Sp1 binding sites, GATA binding site, MyoD, CREB, MEF2, AP1, NFkappaB, etc). Transfection assays indicated that conserved GA-rich sequences, CREB and a CCAAT box within the first 300 bp upstream of the transcription start site were critical for the gene expression. Electrophoretic mobility shift assays (EMSAs) and chromatin immunoprecipitation (ChIP) assays revealed binding proteins to CREB site in nuclear extracts from myocardial cells. An inhibitory domain was revealed within the sequence between -1,700 to -1,780. Thyroid hormone (T(3)) caused a significant inhibitory effect on ssTnI expression in myocardial cells whereas this effect was not evident in CHO cells.


Assuntos
Miócitos Cardíacos , Regiões Promotoras Genéticas , Troponina I/genética , Animais , Sítios de Ligação , Fator de Ligação a CCAAT , Células CHO , Clonagem Molecular , Cricetinae , Cricetulus , Camundongos , Elementos Reguladores de Transcrição , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Tri-Iodotironina/farmacologia
19.
Appl Opt ; 46(2): 147-53, 2007 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-17268556

RESUMO

We use a planar linear grating with varied line-space grooves to introduce a tailored one-dimensional phase variation profile that results in an aberrated point-spread function at the focal plane. A design procedure for the period chirp map for such gratings is developed. As an example, we present theoretical and experimental results on a mechanically ruled, varied line-space echelle grating in single-mode fiber-coupled optical multiplexers in the wavelength region of 1545 nm. The varied line-space grating changes the multiplexer's Gaussian spectral response function to a flat-top dependence with reduced sensitivity to source laser wavelength drift.

20.
Cell Death Differ ; 14(1): 116-27, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16645633

RESUMO

The slow Wallerian degeneration protein (Wld(S)), a fusion protein incorporating full-length nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1), delays axon degeneration caused by injury, toxins and genetic mutation. Nmnat1 overexpression is reported to protect axons in vitro, but its effect in vivo and its potency remain unclear. We generated Nmnat1-overexpressing transgenic mice whose Nmnat activities closely match that of Wld(S) mice. Nmnat1 overexpression in five lines of transgenic mice failed to delay Wallerian degeneration in transected sciatic nerves in contrast to Wld(S) mice where nearly all axons were protected. Transected neurites in Nmnat1 transgenic dorsal root ganglion explant cultures also degenerated rapidly. The delay in vincristine-induced neurite degeneration following lentiviral overexpression of Nmnat1 was significantly less potent than for Wld(S), and lentiviral overexpressed enzyme-dead Wld(S) still displayed residual neurite protection. Thus, Nmnat1 is significantly weaker than Wld(S) at protecting axons against traumatic or toxic injury in vitro, and has no detectable effect in vivo. The full protective effect of Wld(S) requires more N-terminal sequences of the protein.


Assuntos
Axônios/fisiologia , NAD/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Nicotinamida-Nucleotídeo Adenililtransferase/fisiologia , Degeneração Walleriana/prevenção & controle , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NAD/farmacologia , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Nicotinamida-Nucleotídeo Adenililtransferase/genética , Mutação Puntual , Resveratrol , Neuropatia Ciática/induzido quimicamente , Neuropatia Ciática/prevenção & controle , Estilbenos/farmacologia
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