Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Phys Chem Chem Phys ; 25(45): 31363-31373, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37961825

RESUMO

Nonadiabatic molecular dynamics simulations with a global switching algorithm have been performed at the TD-CAM-B3LYP-D3/def2-SVP level of theory for ultrafast photo-induced ring-opening and isomerization reactions upon S1 excitation for 2,2-diphenyl-2H-chromene (DPC). Both DPC-T and DPC-C conformers undergo ring-opening relaxation and isomerization pathways accompanied with pyran conformation conserved and converted on the S1 or S0 states via competition and cooperation between C-O bond dissociation and pyran inversion motions. Upon S1 excitation, the DPC-T mainly relaxes to the T-type conical intersection region and thus yields a higher ring-opening efficiency with a faster S1 decay and intermediate formation than those of the DPC-C mainly relaxing to C-type conical intersection. The simulated ring-opening quantum yield for DPC-T (DPC-C) is 0.91 (0.76), which is in good agreement with the experimental value of 0.7-0.9, and the thermal weight averaged lifetimes are estimated as 182.0 fs, 228.6 fs, and 1262.4 fs for the excited-state decay, intermediate formation, and ring-opening product, respectively. These time constants are in good agreement with the experimentally measured τ1 time constant of 190-450 fs and τ2 time constant of 1000-1800 fs. The present work could be a valuable reference for understanding the nature of the photorelaxation mechanisms of DPC, and could help to develop DPC-based photoresponsive materials.

2.
Biochem Biophys Res Commun ; 625: 188-195, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988459

RESUMO

Hepatocellular carcinoma (HCC) has been a long-time public health problem impacting people's heath and challenging healthcare professions because of its poor prognosis and high lethality. More and more evidence indicated the important role of long non-coding RNAs (lncRNAs) in carcinogenesis and cancer metabolism in a variety of cancer types. In this study, we found that FIRRE, a recently identified cancer-associated lncRNA located on chromosome X, is highly expressed in HCC cell lines and tissue samples, and its expression is positively correlated with poor HCC prognosis. In vitro and in vivo functional analyses showed that FIRRE could promote the proliferation, migration, and invasion of HCC. As for the potential mechanism, FIRRE specifically binds to the splicing factor MBNL3 to affect the expression of PXN to regulate the pathological characteristics of HCC cells. In summary, our study showed that the lncRNA FIRRE is a cancer promoting factor and may be a potential biomarker for the prognosis and drug target for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Paxilina/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Regulação para Cima
3.
Opt Express ; 29(2): 2142-2152, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726415

RESUMO

A multiple reflections-enhanced fiber-optic photoacoustic (PA) gas sensor for gas micro-leakage is introduced. Multiple reflections of the excitation laser occur on the inner surface of a reflective ring to enhance the PA signal. The PA signal is obtained by measuring the deflection of the gold-coated poly (phenylene sulfide) (PPS) diaphragm with a Fabry-Perot interferometer (FPI). The second harmonic wavelength modulation spectrum (2f-WMS) technology can essentially eliminate the fundamental frequency noise generated by the wavelength-independent absorption of the reflective ring. Experimental results show that the PA signal can be effectively enhanced 11.7 times by the multiple reflections optical path compare with the double-pass optical path. The minimum detection limit of the system is achieved to be 23.6 ppb. The designed PA gas sensor is suited for remote detection of gas micro-leakage.

4.
Neuroimage ; 147: 488-499, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27986608

RESUMO

Hypoxia can induce physiological changes. This study aims to explore effects of high-altitude (HA) hypoxia on cerebral iron concentration. Twenty-nine healthy sea-level participants were tested shortly before and after approximately 4-week adaptation to the HA environment at fQinghai-Tibet Plateau (4200m), and were re-investigated after re-adaptation to the sea-level environment one year later. Iron concentration was quantified with quantitative susceptibility mapping (QSM), and the results were compared with transverse relaxation rate (R*2) measurements. The variations of magnetic susceptibility indicate that the iron concentration in gray matter regions, especially in basal ganglia, including caudate nucleus, putamen, globus pallidus and substantia nigra, increases significantly after HA exposure. This increase appears consistent with the conclusion from R*2 value variations. However, unlike QSM, the R*2 value fails to demonstrate the statistical difference of iron content in red nucleus. The re-investigation results show that most variations are recovered after sea-level re-adaptation for one year. Additionally, hemisphere- and gender-related differences in iron concentration changes were analyzed among cerebral regions. The results show greater possibilities in the right hemisphere and females. Further studies based on diffusion tensor imaging (DTI) suggest that the fractional anisotropy increases and the mean diffusivity decreases after HA exposure in six deep gray matter nuclei, with linear dependence on iron concentration only in putamen. In conclusion, the magnetic susceptibility value can serve as a quantitative marker of brain iron, and variations of regional susceptibility reported herein indicate that HA hypoxia can result in significant iron deposition in most deep gray matter regions. Additionally, the linear dependence of DTI metrics on iron concentration in putamen indicates a potential relationship between ferritin and water diffusion.


Assuntos
Adaptação Fisiológica/fisiologia , Altitude , Gânglios da Base/metabolismo , Substância Cinzenta/metabolismo , Hipóxia/metabolismo , Ferro/metabolismo , Imageamento por Ressonância Magnética/métodos , Adulto , Gânglios da Base/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Hipóxia/diagnóstico por imagem , Masculino , Fatores Sexuais , Adulto Jovem
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 42(11): 951-6, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25620259

RESUMO

OBJECTIVE: To explore the effect of Schlafen 1 (Slfn1) on the migration of endothelial progenitor cells (EPCs). METHODS: Rat bone marrow derived EPCs were isolated and cultured. Ad-Slfn1, ShRNA-Slfn1, ShRNA-control and Ad-control were transfected into EPCs respectively. The mRNA expression of Slfn1 and Cyclin D1 was examined by reverse transcriptase-PCR, and their protein expression was detected by Western blot. The migration of EPCs was examined by a modified Boyden chamber assay.EPCs cell cycle was determined using flow cytometry analysis. RESULTS: Forty-eight hours after ShRNA-Slfn1 transfection, the mRNA and protein expression of Slfn1 in EPCs was significantly down-regulated compared to ShRNA-control EPCs (P < 0.05). Transfection of Ad-Slfn1 reversed these changes.Overexpression of Slfn1 reduced the migration capacity of EPCs while the silencing of Slfn1 by shRNA-Slfn1 increased the migration capacity of EPCs.In addition, cell cycle was arrested at G1 phase in Slfn1 overexpression group while transfection of shRNA-Slfn1 reversed these responses.Interestingly, the mRNA and protein expression of Cyclin D1 was significantly up-regulated after shRNA-Slfn1 transfection compared to ShRNA-control group (all P < 0.05), but overexpression of Slfn1 reversed these results, suggesting Cyclin D1 was involved in regulating EPCs cell cycle via Slfn1 signaling. CONCLUSIONS: Slfn1 could reduce the migration capacity of EPCs via Cyclin D1 pathway.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Movimento Celular , Ciclina D1/fisiologia , Células Progenitoras Endoteliais , Animais , Ciclo Celular , Divisão Celular , Regulação para Baixo , Citometria de Fluxo , Técnicas In Vitro , RNA Mensageiro , RNA Interferente Pequeno , Ratos , Transfecção , Regulação para Cima
6.
Front Genet ; 14: 1208102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529778

RESUMO

Background: Thalassemia is the most prevalent monogenic disorder caused by an imbalance between the α- and ß-globin chains as a result of pathogenic variants in the α- or ß-globin genes. Novel or complex structural changes in globin genes are major hurdles for genetic consulting and prenatal diagnosis. Methods: From 2020 to 2022, genetic analysis was performed on 1,316 families suspected of having children with thalassemia major, including 42 pregnant couples suspected of being thalassemia carriers with rare variants. Multiple techniques including multiplex ligation-dependent probe amplification (MLPA), Sanger sequencing, targeted next-generation sequencing, and single-molecule real-time (SMRT) sequencing were used to diagnose rare thalassemia. Results: The rate of prenatal diagnosis for rare thalassemia variants was 3.19% (42/1,316). The most prevalent alleles of α- and ß-thalassemia are Chinese Gγ(Aγδß)0and -- THAI deletion. In addition, ten rare complex genotypes include one Chinese Gγ(Aγδß)0 deletion combined with HBG1-HBG2 fusion, two rare deletions at HBB gene (hg38, Chr11: 5224211-5232470, hg38, Chr11: 5224303-5227790), one complete 7,412 bp fusion gene for anti-Lepore Hong Kong, two complex rearrangements of the α-globin gene cluster, two novel duplications, and two rare large deletions in the α-globin gene cluster. Conclusion: Accurate gene diagnosis for probands with combined molecular biology techniques is the key to prenatal diagnosis of rare thalassemia.

7.
J Mol Model ; 27(6): 167, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33987741

RESUMO

Herein, a series of organic molecules were designed through locating different substituents on the compound (WD8-c-1) to develop their performances used as the sensitizers in the field of dye-sensitized solar cells. The geometry and relevant electronic properties of WD8-c-1 and its derivatives were simulated at the B3LYP/6-31G(d,p) level. The absorption spectra were calculated using the TD-PBE0/6-31+G(d,p) method. These calculated results show that the type and position of the substituents strongly affected the distributions of frontier molecular orbitals and the energy gaps for the WD8-c-1-derived molecules. The reorganization energies results reveal that their hole charge transfer rates are higher than that of the representative hole transport material. Moreover, the mobility of the representative WD8-c-1 derivative also has been simulated. The starburst triphenylamine with suitable substituent has the more suitable FMO energy to match those of TiO2, broad absorption region, smaller reorganization energies, and high hole mobility.

8.
Zhonghua Xin Xue Guan Bing Za Zhi ; 37(9): 781-4, 2009 Sep.
Artigo em Zh | MEDLINE | ID: mdl-20128373

RESUMO

OBJECTIVE: To evaluate the effects on cardiac remodeling post transcatheter closure by Amplatzer septal occluder selected by oval circumference formula in patients with atrial septal defect (ASD). METHODS: A total of 146 patients with ASD (68 males,mean 33.5 years) treated by transcatheter closure with the Amplatzer occluder were enrolled in this study. The diameter of defects was corrected with the oval circumference formula (group A, 73 cases) or by echocardiography (group B, 73 cases). Cardiac remodeling was assessed by transthoracic echocardiography (TTE) before the procedure, 3 days, 3 months and 6 months after ASD closure. RESULTS: The mean ASD diameter was similar between the two groups [(20.16 +/- 4.98) mm vs. (21.36 +/- 5.69) mm, P > 0.05] and the mean diameter of the selected occluder of group A was significantly smaller than that in group B [(21.95 +/- 6.78) mm vs. (25.85 +/- 6.75) mm, P < 0.05]. Procedural success rate was identical between the two groups (97.3%) and the defects were completely occluded and there was no residual shunt during the 6 months follow up period, there were also no complications during and after the procedure. The lateral diameter of right atrial (RALD), the diastolic diameter of right ventricle (RVDD), RALD/LALD, RVDD/LVDD and pulmonary diameter (PD) were significantly decreased while the lateral diameter of left atrial (LALD) and left ventricle (LVDD) were significantly increased post ASD closure in both groups. At 6 months follow up, RALD decreased by (18.63 +/- 10.59)% in group A versus (10.14 +/- 6.59)% in group B, LALD increased by (13.42 +/- 8.38)% in group A versus (9.28 +/- 4.95)% in group B and RALD/LALD ratio decreased by (26.35 +/- 11.24)% in group A versus (13.98 +/- 8.96)% in groups B (all P < 0.05). CONCLUSION: ASD occluder selection based on the oval circumferen ce formula is superior to that made by echocardiography in terms of more favorable cardiac remodeling post ASD closure.


Assuntos
Cateterismo Cardíaco/instrumentação , Comunicação Interatrial/terapia , Remodelação Ventricular , Adolescente , Adulto , Idoso , Cateterismo Cardíaco/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Chin Med Sci J ; 23(3): 187-92, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18853856

RESUMO

OBJECTIVE: To evaluate the feasibility of whole body diffusion weighted imaging (DWI) in the diagnosis of metastatic tumor. METHODS: Fifty-six patients (40 males and 16 females, age ranging from 29 to 84 years with a mean age of 57 years) with a variety of primary tumors were investigated by whole body DWI combined with computed tomography (CT) and/or conventional magnetic resonance imaging (MRI) scans. Twelve patients underwent positron emission tomography. The final diagnosis was made on the basis of CT or high resolution CT result for lung lesion and MRI or CT result for skull, abdomen and other parts. All tumors were classified into four groups by their diameter: below 1.0 cm, 1.0-1.9 cm, 2.0-2.9 cm, and above 3.0 cm. The sensitivity and specificity of whole body DWI in the detection of metastatic tumor were analyzed. RESULTS: The sensitivities of whole body DWI for screening metastasis of the four groups were 38%, 75%, 97%, and 100%, respectively. Whole body DWI showed the highest sensitivity and specificity for detecting metastasis of the skeletal system. It was difficult to find metastatic tumor whose diameter was below 1.0 cm, or lymph nodes located in the pelvis with diameter below 2.0 cm. CONCLUSIONS: Whole body DWI is a promising method in the diagnosis of metastastic tumors. With the perfection of scanning parameter, whole body DWI should be a new effective whole body technique for tumor detection.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Metástase Neoplásica , Neoplasias , Imagem Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/patologia , Estadiamento de Neoplasias , Neoplasias/diagnóstico , Neoplasias/patologia , Sensibilidade e Especificidade
11.
Ultramicroscopy ; 107(10-11): 1068-77, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17573195

RESUMO

Atomic force microscopy (AFM) studies of cementitious materials are limited, mainly due to the lack of appropriate sample preparation techniques. In porous autoclaved aerated concrete (AAC), calcium silicate hydrate (C-S-H) is produced in its crystalline form, tobermorite. The crystals are lath-like with a length of several micrometers. In this work, we demonstrate the application of nanomanipulators to separate an individual tobermorite crystal from the bulk AAC for subsequent AFM investigations. The nanomanipulators are operated directly in an environmental scanning electron microscope (ESEM). We studied the interaction between moisture and the tobermorite surface under controlled relative humidity (RH). The results of topography and adhesion force measurements with AFM suggest that the surface of tobermorite is hydrophobic, which contrasts the macroscopic material properties (e.g. moisture transport in capillary pores).

12.
High Alt Med Biol ; 18(1): 20-26, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28266873

RESUMO

Zhang, Jiaxing, Ji Chen, Cunxiu Fan, Jinqiang Li, Jianzhong Lin, Tianhe Yang, and Ming Fan. Alteration of spontaneous brain activity after hypoxia-reoxygenation: A resting-state fMRI study. High Alt Med Biol. 18:20-26, 2017.-The present study was designed to investigate the effect of hypoxia-reoxygenation on the spontaneous neuronal activity in brain. Sixteen sea-level (SL) soldiers (20.5 ± 0.7 years), who garrisoned the frontiers in high altitude (HA) (2300-4400 m) for two years and subsequently descended to sea level for one to seven days, were recruited. Control group consisted of 16 matched SL natives. The amplitude of low-frequency fluctuations (ALFF) of regional brain functional magnetic resonance imaging signal in resting state and functional connectivity (FC) between brain regions was analyzed. HA subjects showed significant increases of ALFF at several sites within the bilateral occipital cortices and significant decreases of ALFF in the right anterior insula and extending to the caudate, putamen, inferior frontal orbital cortex, temporal pole, and superior temporal gyrus; lower ALFF values in the right insula were positively correlated with low respiratory measurements. The right insula in HA subjects had increases of FC with the right superior temporal gyrus, postcentral gyrus, rolandic operculum, supramarginal gyrus, and inferior frontal triangular area. We thus demonstrated that hypoxia-reoxygenation had influence on the spontaneous neuronal activity in brain. The decrease of insular neuronal activity may be related to the reduction of ventilatory drive, while the increase of FC with insula may indicate a central compensation.


Assuntos
Altitude , Encéfalo/fisiopatologia , Hipóxia/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Descanso/fisiologia , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , China , Humanos , Hipóxia/diagnóstico por imagem , Masculino , Militares , Consumo de Oxigênio/fisiologia , Adulto Jovem
13.
Brain Behav ; 6(9): e00512, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27688941

RESUMO

BACKGROUND: Structural and functional networks can be reorganized to adjust to environmental pressures and physiologic changes in the adult brain, but such processes remain unclear in prolonged adaptation to high-altitude (HA) hypoxia. This study aimed to characterize the interhemispheric functionally and structurally coupled modifications in the brains of adult HA immigrants. METHODS: We performed resting-state functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) in 16 adults who had immigrated to the Qinghai-Tibet Plateau (2300-4400 m) for 2 years and in 16 age-matched sea-level (SL) controls. A recently validated approach of voxel-mirrored homotopic connectivity (VMHC) was employed to examine the interhemispheric resting-state functional connectivity. Areas showing changed VMHC in HA immigrants were selected as regions of interest for follow-up DTI tractography analysis. The fiber parameters of fractional anisotropy and fiber length were obtained. Cognitive and physiological assessments were made and correlated with the resulting image metrics. RESULTS: Compared with SL controls, VMHC in the bilateral visual cortex was significantly increased in HA immigrants. The mean VMHC value extracted within the visual cortex was positively correlated with hemoglobin concentration. Moreover, the path length of the commissural fibers connecting homotopic visual areas was increased in HA immigrants, covarying positively with VMHC. CONCLUSIONS: These observations are the first to demonstrate interhemispheric functional and structural connectivity resilience in the adult brain after prolonged HA acclimatization independent of inherited and developmental effects, and the coupled modifications in the bilateral visual cortex indicate important neural compensatory mechanisms underlying visual dysfunction in physiologically well-acclimatized HA immigrants. The study of human central adaptation to extreme environments promotes the understanding of our brain's capacity for survival.

14.
Artigo em Inglês | MEDLINE | ID: mdl-27555761

RESUMO

BACKGROUND AND OBJECTIVE: Airflow limitation in chronic obstructive pulmonary disease (COPD) results in a decrease in oxygen transport to the brain. The aim of the present study was to explore the alteration of spontaneous brain activity induced by hypoxia in patients with COPD. PATIENTS AND METHODS: Twenty-five stable patients with COPD and 25 matching healthy volunteers were investigated. Amplitude of low-frequency fluctuation (ALFF) of blood oxygenation level-dependent signal at resting state in the brain was analyzed using functional magnetic resonance imaging. RESULTS: Whole-brain analysis using functional magnetic resonance imaging revealed significant decreases in ALFF in the bilateral posterior cingulate gyri and right lingual gyrus and an increase in ALFF in the left postcentral gyrus of patients with COPD. After controlling for SaO2, patients with COPD only showed an increase in ALFF in the left postcentral gyrus. Region of interest analysis showed a decrease in ALFF in the left precentral gyrus and an increase in ALFF in the left caudate nucleus of patients with COPD. In all subjects, ALFF in the bilateral posterior cingulate gyri and right lingual gyrus showed positive correlations with visual reproduction. CONCLUSION: We demonstrated abnormal spontaneous brain activity of patients with COPD, which may have a pathophysiologic meaning.


Assuntos
Ondas Encefálicas , Encéfalo/fisiopatologia , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Encéfalo/metabolismo , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Circulação Cerebrovascular , Feminino , Humanos , Pulmão/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/diagnóstico
15.
High Alt Med Biol ; 17(1): 16-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26906285

RESUMO

The human brain is intrinsically plastic such that its functional architecture can be reorganized in response to environmental pressures and physiological changes. However, it remains unclear whether a compensatory modification of spontaneous neural activity occurs in adult brain during prolonged high-altitude (HA) adaptation. In this study, we obtained resting-state functional magnetic resonance (MR) images in 16 adults who have immigrated to Qinghai-Tibet Plateau (2300-4400 m) for 2 years and in 16 age-matched sea level (SL) controls. A validated regional homogeneity (Reho) method was employed to investigate the local synchronization of resting-state functional magnetic resonance imaging (fMRI) signals. Seed connectivity analysis was carried out subsequently. Cognitive and physiological assessments were made and correlated with the image metrics. Compared with SL controls, global mean Reho was significantly increased in HA immigrants as well as a regional increase in the right inferolateral sensorimotor cortex. Furthermore, mean z-Reho value extracted within the inferolateral sensorimotor area showed trend-level significant inverse correlation with memory search reaction time in HA immigrants. These observations, for the first time, provide evidence of adult brain resilience of spontaneous neural activity after long-term HA exposure without inherited and developmental effects. Resting-state fMRI could yield valuable information for central mechanisms underlying respiratory and cognitive compensations in adults during prolonged environmentally hypoxic adaptation, paving the way for future HA-adaptive training.


Assuntos
Aclimatação/fisiologia , Doença da Altitude/fisiopatologia , Altitude , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Doença da Altitude/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Humanos , Masculino , Descanso/fisiologia , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/fisiopatologia , Tibet , Adulto Jovem
16.
Sci Rep ; 6: 33596, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27633944

RESUMO

A large proportion of lowlanders ascending to high-altitude (HA) show no signs of mountain sickness. Whether their brains have indeed suffered from HA environment and the persistent sequelae after return to lowland remain unknown. Thirty-one sea-level college students, who had a 30-day teaching on Qinghai-Tibet plateau underwent MRI scans before, during, and two months after HA exposure. Brain volume, cortical structures, and white matter microstructure were measured. Besides, serum neuron-specific enolase (NSE), C-reactive protein, and interleukin-6 and neuropsychiatric behaviors were tested. After 30-day HA exposure, the gray and white matter volumes and cortical surface areas significantly increased, with cortical thicknesses and curvatures changed in a wide spread regions; Anisotropy decreased with diffusivities increased in multiple sites of white matter tracts. Two months after HA exposure, cortical measurements returned to basal level. However, increased anisotropy with decreased diffusivities was observed. Behaviors and serum inflammatory factor did not significant changed during three time-point tests. NSE significantly decreased during HA but increased after HA exposure. Results suggest brain swelling occurred in people without neurological signs at HA, but no negative sequelae in cortical structures and neuropsychiatric functions were left after the return to lowlands. Reoxygenation changed white matter microstructure.


Assuntos
Doença da Altitude/patologia , Altitude , Encéfalo/anormalidades , Doença da Altitude/psicologia , Anisotropia , Temperatura Corporal , Encéfalo/metabolismo , Difusão , Feminino , Humanos , Pulmão/patologia , Masculino , Testes Neuropsicológicos , Tamanho do Órgão , Oxigênio/metabolismo , Adulto Jovem
17.
Int J Clin Exp Pathol ; 8(10): 12216-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26722406

RESUMO

Dilated cardiomyopathy is the most frequent form of myocardial disease. Many factors contribute to dilated cardiomyopathy, for instance, long-term use of doxorubicin, one of the anthracyclines clinically used for cancer chemotherapy, result in dilated cardiomyopathy and congestive heart failure. However, the mechanism underlining doxorubicin-induced cardiomyocyte is still not fully understood. In this study, we evaluate the effects and their mechanisms of PPARα and PGC-1α pathways in doxorubicin induced mice cardiomyocytes. In vitro, cardiomyocytes isolated from hearts of adult FVB/NJ mice were treated with doxorubicin, GW 6471 (PPARα inhibitors) and WY14643 (PPARα agonists). The expression of PPARα and PGC-1α were detected via western blotting and Quantitative Real-Time PCR methods. Changes in energy and substrate metabolism were analyzed. MTT and flow cytometry were used for cell proliferation and apoptosis analysis. We detected expression of PPARα and PGC-1α was significantly higher in control group than doxorubicin group. Mitochondrial dysfunction was found in doxorubicin group including lower content of high-energy phosphates, significantly decreased mitochondrial ANT transport activity and markedly reduced mitochondrial membrane potential compared with control group. Metabolic remodeling existed in doxorubicin group because of higher concentration of free fatty acid and glucose consumption than of control group. More accumulations of reactive oxygen species were detected in doxorubicin group. The decreased cell viability and increased cell apoptosis observed in doxorubicin group. Severe apoptosis in doxorubicin group was verified by a set of markers including Bax, Bcl-2, cytosolic cytochrome c and caspase-3 up-regulation expression. These findings indicate that the PPARα and PGC-1α are closely involved in energy metabolism remodeling and apoptosis in cardiomyocytes.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Metabolismo Energético/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , PPAR alfa/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Oxazóis/farmacologia , PPAR alfa/agonistas , PPAR alfa/antagonistas & inibidores , PPAR alfa/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Pirimidinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Tirosina/análogos & derivados , Tirosina/farmacologia , Regulação para Cima/efeitos dos fármacos
18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 21(5): 819-23, 2004 Oct.
Artigo em Zh | MEDLINE | ID: mdl-15553866

RESUMO

Polygraph has become a necessary instrument in interventional cardiology and fundamental research of medicine up to the present. In this study, a LabView development system (DS) (developed by NI in U.S.) used as software platform, a DAQ data acquisition module and universal computer used as hardware platform, were creatively coupled with our self-made low noise multi-channels preamplifier to develop Multi-channels electrocardiograph. The device possessed the functions such as real time display of physiological process, digit highpass and lowpass, 50Hz filtered and gain adjustment, instant storing, random playback and printing, and process control stimulation. Besides, it was small-sized, economically practical and easy to operate. It could advance the spread of cardiac intervention treatment in hospitals.


Assuntos
Eletrocardiografia/instrumentação , Monitorização Intraoperatória , Processamento de Sinais Assistido por Computador , Monitorização Fisiológica , Software
19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 21(4): 650-3, 2004 Aug.
Artigo em Zh | MEDLINE | ID: mdl-15357453

RESUMO

A temporary demand pacemaker with electrocardiosignal display is introduced in this paper. Double way low-noise electrocardiosignal preamplifier, amplitude limiter, high and low pass filter, 50 Hz notch filter, TTL level generator and stimulating pulse formation circuit are components of the hardware electrocircuit. The demand pacing and the electrocardiosignal display are separately controlled by the software in which the double microcontrollers communications technique is used. In this study, liquid crystal display is firstly used in body surface electrocardiosignal display or intracardial electrophysiologic signal display when the temporary demand pacemaker is installed and put into use. The machine has proven clinically useful and can be of wide appliation.


Assuntos
Eletrocardiografia , Marca-Passo Artificial , Humanos
20.
Int J Clin Exp Med ; 7(9): 2435-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25356095

RESUMO

OBJECTIVE: This study aims to investigate the effects and their mechanisms of PPARα and PGC-1α pathways in doxorubicin induced dilated cardiomyopathy in mice. METHODS: The model of dilated cardiomyopathy (DCM) was established by injecting doxorubicin in mice. The 40 surviving mice were divided randomly into control group, doxorubicin model group, PPARα inhibitor and PPARα agonist group. The PPARα/PGC-1α proteins were detected. The size of adenine acid pool (ATP, ADP, AMP) and phosphocreatine (Pcr) in mitochondria were measured by HPLC. The ANT activity was detected by the atractyloside-inhibitor stop technique. The echocardiography and hemodynamic changes were detected in each group after PPARα inhibitor and PPARα agonist treatment for 2 weeks. RESULTS: The DOX induced DCM model were successfully established. The expression of PPARα and PGC-1α protein level in normal group were significantly higher than that in DOX model group (P<0.05). Both the high-energy phosphate content and the transport activity of ANT were decreased in DOX group (P<0.05), and the hemodynamic parameters were disorder (P<0.01). Compared with Dox group, PPARα inhibitor intervention significantly reduce the expression of PPARα/PGC-1α, high-energy phosphate content in the mitochondria had no significant change (P>0.05), but the ANT transport activity of mitochondria decreased significantly (P<0.05), the left ventricular function decreased. On the other side, PPARα agonist intervention significantly increased the expression of PPARα and PGC-1α, improved transport activity of ANT, the hemodynamic parameters was ameliorated (P<0.05), but the high-energy phosphate content of mitochondria did not change significantly (P>0.05). CONCLUSION: There was lower expression of PPARα and PGC-1α in DOC induced DCM in mice. Promotion of PPARα can improve myocardia energy metabolism and delay the occurrence of heart failure.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA