Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
BMC Cancer ; 22(1): 981, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104662

RESUMO

OBJECTIVE: To investigate the role of NudCD1 in spindle assembly checkpoint regulation and in the prognosis of colorectal cancer.  METHODS: Immunohistochemical staining was used to detect in situ expression of NudCD1 in 100 colorectal cancer tissue samples. A chi-square test was used to analyse the correlation between the NudCD1 protein expression level of the cancer tissues and clinicopathological features. The Kaplan-Meier survival analysis was used to assess the correlation between the NudCD1 mRNA expression and the three-year survival of patients with colorectal cancer. The impact of NudCD1 on the development of colorectal cancer and the underlying molecular mechanisms were assessed by flow cytometry cell cycle and apoptosis assays after lentiviral overexpression of NudCD1 in two colorectal cancer cell lines. Quantitative real-time PCR was used to assess mRNA expression of the cellular spindle assembly checkpoint genes BUB1, BUBR1, MAD1, CDC20 and MPS1, as well as the downstream genes LIS1, DYNC1H1, and DYNLL1 in the NudC/LIS1/dynein pathway. RESULTS: Compared with normal intestinal tissue (8.00% with high expression), the expression of NudCD1 protein in colorectal cancer tissue was significantly higher (58.00% with high expression, P < 0.01). In addition, expression of NudCD1 significantly correlated with the degree of tumour differentiation and the TNM staging (P < 0.01), as well as the depth of invasion of the primary tumour and lymph node metastasis (P < 0.05). However, there was no correlation with gender, age, tumour site, gross type, tumour size or distant metastasis. The Kaplan-Meier survival analysis showed that patients with high NudCD1 expression in colorectal cancer tissues had a significantly shorter survival time than those with low expression of NudCD1 (P < 0.01). Compared with the transfection of the empty vector, colon cancer HT-29 cells with overexpressed NudCD1 had significantly increased mRNA levels of BUBR1, MPS1 and LIS1. The DNA synthesis phase (S phase) was significantly shorter in cells overexpressing NudCD1 than in the control group (43.83% ± 1.57%, P < 0.05), while there was no difference in apoptosis in the two groups. CONCLUSION: NudCD1 can serve as a valuable prognostic marker for colorectal cancer. It may be involved in the regulation of spindle-assembly checkpoint-gene expression and the LIS1 pathway of colorectal cancer cells.


Assuntos
Neoplasias Colorretais , Pontos de Checagem da Fase M do Ciclo Celular , 1-Alquil-2-acetilglicerofosfocolina Esterase , Antígenos de Neoplasias , Humanos , Proteínas Associadas aos Microtúbulos , Prognóstico , RNA Mensageiro , Regulação para Cima
2.
Apoptosis ; 25(1-2): 73-91, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31768842

RESUMO

Weightlessness-induced cardiovascular dysfunction can lead to physiological and pathological consequences. It has been shown that spaceflight or simulated microgravity can alter expression profiles of some microRNAs (miRNAs). Here, we attempt to identify the role of miRNAs in human umbilical vein endothelial cells (HUVECs) apoptosis under simulated microgravity. RNA-sequencing and quantitative real-time PCR (qRT-PCR) assays were used to identify differentially expressed miRNAs in HUVECs under simulated microgravity. Then we obtained the target genes of these miRNAs through target analysis software. Moreover, GO and KEGG enrichment analysis were performed. The effects of these miRNAs on HUVECs apoptosis were evaluated by flow cytometry, Western blot and Hoechst staining. Furthermore, we obtained the target gene of miR-27b-5p by luciferase assay, qRT-PCR and Western blot. Finally, we investigated the relationship between this target gene and miR-27b-5p in HUVECs apoptosis under normal gravity or simulated microgravity. We found 29 differentially expressed miRNAs in HUVECs under simulated microgravity. Of them, the expressions of 3 miRNAs were validated by qRT-PCR. We demonstrated that miR-27b-5p affected HUVECs apoptosis by inhibiting zinc fingers and homeoboxes 1 (ZHX1). Our results reported here demonstrate for the first time that simulated microgravity can alter the expression of some miRNAs in HUVECs and miR-27b-5p may protect HUVECs from apoptosis under simulated microgravity by targeting ZHX1.


Assuntos
Apoptose , Células Endoteliais da Veia Umbilical Humana/citologia , Ausência de Peso/efeitos adversos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Células Endoteliais da Veia Umbilical Humana/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Apoptosis ; 24(9-10): 812-825, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31359205

RESUMO

Astronauts exposed to a gravity-free environment experience cardiovascular deconditioning that causes post-spaceflight orthostatic intolerance and other pathological conditions. Endothelial dysfunction is an important factor responsible for this alteration. Our previous study showed enhanced autophagy in endothelial cells under simulated microgravity. The present study explored the cytoprotective role of autophagy under microgravity in human umbilical vein endothelial cells (HUVECs). We found that clinorotation for 48 h induced apoptosis and endoplasmic reticulum (ER) stress in HUVECs. ER stress and the unfolded protein response (UPR) partially contributed to apoptosis under clinorotation. Autophagy partially reduced ER stress and restored UPR signaling by autophagic clearance of ubiquitin-protein aggregates, thereby reducing apoptosis. In addition, the ER stress antagonist 4-phenylbutyric acid upregulated autophagy in HUVECs. Taken together, these findings indicate that autophagy plays a protective role against apoptosis under clinorotation by clearing protein aggregates and partially restoring the UPR.


Assuntos
Apoptose , Gravidade Alterada/efeitos adversos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Fenilbutiratos/farmacologia , Autofagia/efeitos dos fármacos , Linhagem Celular , Estresse do Retículo Endoplasmático , Humanos , Substâncias Protetoras/farmacologia , Rotação/efeitos adversos , Resposta a Proteínas não Dobradas
4.
Cell Physiol Biochem ; 41(1): 227-238, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28214845

RESUMO

BACKGROUND/AIMS: Microgravity leads to hydrodynamic alterations in the cardiovascular system and is associated with increased angiogenesis, an important aspect of endothelial cell behavior to initiate new vessel growth. Given the critical role of Rho GTPase-dependent cytoskeleton rearrangement in cell migration, small GTPase RhoA might play a potential role in microgravity-induced angiogenesis. METHODS: We examined the organization of actin filaments by FITC-conjugated phalloidin staining, as well as the expression and activity of RhoA by quantitative PCR and Western blot, in human umbilical vein endothelial cells (HUVECs) under normal gravity and simulated microgravity. Effect of simulated microgravity on the wound closure and tube formation in HUVECs, and their dependence on RhoA, were also analyzed by cell migration and tube formation assays. RESULTS: We show that in HUVECs actin filaments are disorganized and RhoA activity is reduced by simulated microgravity. Blocking RhoA activity either by C3 transferase Rho inhibitor or siRNA knockdown mimicked the effect of simulated microgravity on inducing actin filament disassembly, followed by enhanced wound closure and tube formation in HUVECs, which closely resembled effects seen on microgravity-treated cells. In contrast, overexpressing RhoA in microgravity-treated HUVECs restored the actin filaments, and decreased wound closure and tube formation abilities. CONCLUSION: These results suggest that RhoA inactivation is involved in the actin rearrangement-associated angiogenic responses in HUVECs during simulated microgravity.


Assuntos
Citoesqueleto de Actina/fisiologia , Actinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Movimento Celular , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Microscopia de Fluorescência , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Simulação de Ausência de Peso , Proteína rhoA de Ligação ao GTP/antagonistas & inibidores , Proteína rhoA de Ligação ao GTP/genética
5.
J Transl Med ; 15(1): 37, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28202073

RESUMO

BACKGROUND: Macrophages (Mφs) constitute a major component of the leukocyte infiltrate and perform distinct roles in different tumor microenvironments. This study aimed to characterize the distribution, composition and prognostic value of Mφs in hepatocellular carcinoma (HCC) and gastric cancer (GC). METHODS: Immunohistochemistry and immunofluorescence were used to identify Mφ subsets in HCC and GC tissues. Kaplan-Meier analysis and Cox regression models were applied to estimate the overall survival (OS) for HCC and GC patients. RESULTS: The results showed that the density of Mφs decreased in the intra-tumor region (IT) of HCC, but remarkably increased in the IT of GC, as compared with their non-tumor regions (NT). In HCC, most CD68+ Mφs were CD204+ and CD169+ cells in the NT region; however, there was a significant decrease in the percentage of CD169+ Mφ in the IT region. In contrast, CD68+ Mφs comprised a smaller percentage of CD204+ than the CD169+ subpopulation in the NT region, while more CD204+ but fewer CD169+ cells were present in the IT region of GC. The density of CD204+ Mφs correlated with poor prognosis in HCC, and CD169+ Mφs were associated with good survival in both HCC and GC. Moreover, the combination of low numbers of CD204+ and high numbers of CD169+ Mφs was associated with improved OS in both GC and HCC. CONCLUSIONS: Mφs display tissue-specific distributions and distinct composition patterns in HCC and GC tissues. Our results suggested that different types of tumors might use diverse strategies to reconstitute Mφ patterns to promote tumor progression.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Macrófagos/patologia , Neoplasias Gástricas/diagnóstico , Adolescente , Adulto , Idoso , Antígenos CD/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Neoplasias Gástricas/patologia , Análise de Sobrevida , Adulto Jovem
6.
Cell Physiol Biochem ; 38(2): 502-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26828798

RESUMO

BACKGROUND/AIMS: The potential role of caveolin-1 in modulating angiogenesis in microgravity environment is unexplored. METHODS: Using simulated microgravity by clinostat, we measured the expressions and interactions of caveolin-1 and eNOS in human umbilical vein endothelial cells. RESULTS: We found that decreased caveolin-1 expression is associated with increased expression and phosphorylation levels of eNOS in endothelial cells stimulated by microgravity, which causes a dissociation of eNOS from caveolin-1 complexes. As a result, microgravity induces cell migration and tube formation in endothelial cell in vitro that depends on the regulations of caveolin-1. CONCLUSION: Our study provides insight for the important endothelial functions in altered gravitational environments.


Assuntos
Cavéolas/metabolismo , Caveolina 1/metabolismo , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/metabolismo , Simulação de Ausência de Peso , Caveolina 1/análise , Movimento Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico Sintase Tipo III/análise , Mapas de Interação de Proteínas
7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(3): 370-2, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-27236899

RESUMO

Pharmacological method state is a method to explain the principle of Chinese herb according to its external phenomenon such as shape, color, texture, features, and so on. The natural attribute of Chinese herb include shape, color, texture, smell, harvesting time, medicinal parts, chemical components, and so on. Though both of them have different key points, the natural attribute of Chinese herb can also be used to explain its medicinal mechanism. Therefore, the correlation research between pharmacological method state and the natural attribute of Chinese herb has some significance.


Assuntos
Pesquisa Biomédica , Medicamentos de Ervas Chinesas/farmacologia
8.
Ann Clin Transl Neurol ; 11(5): 1267-1279, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38651547

RESUMO

OBJECTIVE: The pathological features of immune-mediated necrotizing myopathy (IMNM) are dominated by the infiltration of macrophages. We aimed to perform a histopathologic semiquantitative analysis to investigate the relationship between macrophage markers and prognosis. METHODS: Semiquantitative analysis of histologic features was performed in 62 samples of IMNM. Independent risk factors were identified through univariate and multivariate regression analysis. Cluster analysis was performed using the partitioning around the medoids (PAM) method. Decision tree modeling was utilized to efficiently determine cluster labels for IMNM patients. The validity of the developmental cohort was assessed by accuracy in comparison with the validation cohort. RESULTS: The most enriched groups in patients with IMNM were macrophages expressing CD206 and CD163. In the multivariate logistic regression model, the high density of CD163+ macrophages in perimysial connective tissue increased the risk of unfavorable prognosis (p = 0.025, OR = 1.463, 95% CI: 1.049-2.041). In cluster analysis, patients in Cluster 1, with lower CD163+ macrophage density and inflammatory burden, had a more favorable prognosis. Conversely, patients in Cluster 3, which were enriched for CD163+ macrophages in the perimysial connective tissue, had the most severe clinical features and the worst prognosis. Correlations were found between the density of CD163+ macrophages in connective tissue and symptom duration (R2 = 0.166, p < 0.001), dysphagia (p = 0.004), cardiac involvement (p = 0.021), CK (R2 = 0.067, p = 0.042), CRP (R2 = 0.117, p < 0.001), and ESR (R2 = 0.171, p < 0.001). CONCLUSION: The density of CD163+ macrophages in perimysial connective tissue may serve as a potential marker for the prediction of IMNM prognosis.


Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Tecido Conjuntivo , Macrófagos , Receptores de Superfície Celular , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Tecido Conjuntivo/patologia , Tecido Conjuntivo/imunologia , Macrófagos/patologia , Macrófagos/imunologia , Miosite/patologia , Miosite/imunologia , Prognóstico , Receptores de Superfície Celular/metabolismo
9.
Biochem Cell Biol ; 91(5): 309-14, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24032680

RESUMO

Individuals exposed to extended periods of spaceflight or prolonged 6° head-down-tilt bed rest often suffer from health hazards represented by cardiovascular deconditioning. Many studies have reported that alterations in vascular endothelial cells contribute to cardiovascular dysfunction induced by microgravity. Autophagy, a lysosomal degradation pathway, serves an adaptive role for survival, differentiation, and development in cellular homeostasis, and can be triggered by various environmental stimuli. However, whether autophagy can be induced in endothelial cells by real or simulated microgravity remains to be determined. This study was designed to investigate the effects of simulated microgravity on the activation of autophagy in human umbilical vein endothelial cells (HUVECs). We report here that clinorotation, a simulated model of microgravity, enhances autophagosome formation, increases LC3 and beclin-1 expression, and promotes the conversion of LC3-I to LC3-II in HUVECs. These results demonstrate that simulated microgravity for 48 h activates autophagy of vascular endothelial cells.


Assuntos
Autofagia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Rotação/efeitos adversos , Ausência de Peso/efeitos adversos , Proteínas Reguladoras de Apoptose/biossíntese , Proteína Beclina-1 , Descondicionamento Cardiovascular/fisiologia , Linhagem Celular , Humanos , Proteínas de Membrana/biossíntese , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/metabolismo , Voo Espacial
10.
J Mater Sci Mater Med ; 23(11): 2709-16, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22875606

RESUMO

In this work, blended nanofibrous membranes were prepared by an electrospinning technique with polyvinylpyrrolidone (PVP) K90 as the filament-forming polymer, and emodin, an extract of polygonum cuspidate known as a medicinal plant, as the treatment drug. Detailed analysis of the blended nanofibrous membrane by scanning electron microscopy, Differential scanning calorimetry and X-ray diffraction revealed that emodin was well distributed in the ultrafine fibers in the form of amorphous nanosolid dispersions. Results from attenuated total reflectance Fourier transform infrared spectra suggested that the main interactions between PVP and emodin might be mediated through hydrogen bonding. In vitro dissolution tests proved that the blended nanofibrous membrane produced more desired release kinetics of the entrapped drug (emodin) as compared to the pure drug. Furthermore, wound healing test and histological evaluation revealed that the emodin loaded nanofibrous membrane to be more effective as a healing accelerator thereby proving potential strategies to develop composite drug delivery system as well as promising materials for future therapeutic biomedical applications.


Assuntos
Materiais Biocompatíveis , Portadores de Fármacos , Emodina/química , Membranas Artificiais , Nanofibras , Povidona/química , Cicatrização , Animais , Varredura Diferencial de Calorimetria , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
11.
Mil Med ; 177(2): 163-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22360061

RESUMO

A questionnaire survey was performed for the first time to assess the prevalence of visual symptoms and G-induced loss of consciousness (G-LOC) due to +Gz exposure in the Chinese Air Force (CAF) to determine the effectiveness of current G tolerance training. Responses were received from 594 individuals. Among them, 302 reported at least one episode of some sort of symptoms related to +Gz, including 110 (18.5%) with visual blurring, 231 (38.9%) with greyout, 111 (18.7%) with blackout, and 49 (8.2%) with G-LOC. Incidences were most common in aircrew with 250-1,000 flying hours (53.6%) and were more prevalent in those with fewer on type flying hours (p < 0.001). The most common situation was reported between +5 and 5.9 Gz. The results indicate a fairly high prevalence of visual symptoms and G-LOC among Chinese Air Force aircrew. There remains considerable scope for +Gz education, particularly in the early centrifuge training and selection of rational physical exercises.


Assuntos
Aviação , Hipergravidade/efeitos adversos , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologia , Adulto , Medicina Aeroespacial , China/epidemiologia , Gravitação , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Inquéritos e Questionários , Inconsciência/epidemiologia , Inconsciência/etiologia , Acuidade Visual , Adulto Jovem
12.
Front Cardiovasc Med ; 9: 925254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935626

RESUMO

Normal endothelial function plays a pivotal role in maintaining cardiovascular homeostasis, while endothelial dysfunction causes the occurrence and development of cardiovascular diseases. Yes-associated protein (YAP) and its homolog transcriptional co-activator with PDZ-binding motif (TAZ) serve as crucial nuclear effectors in the Hippo signaling pathway, which are regulated by mechanical stress, extracellular matrix stiffness, drugs, and other factors. Increasing evidence supports that YAP/TAZ play an important role in the regulation of endothelial-related functions, including oxidative stress, inflammation, and angiogenesis. Herein, we systematically review the factors affecting YAP/TAZ, downstream target genes regulated by YAP/TAZ and the roles of YAP/TAZ in regulating endothelial functions, in order to provide novel potential targets and effective approaches to prevent and treat cardiovascular diseases.

13.
Ther Apher Dial ; 26(4): 822-826, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34898008

RESUMO

INTRODUCTION: The aim of this study was to investigate how peritoneal dialysis and other influencing factors affect patients' cognitive function. METHODS: The 85 subjects in the study group were regular patients in our center. The control group included 88 age and gender matched healthy individuals who were with normal renal function. The study subjects' cognitive levels and related factors were analyzed using several screening instruments: the cognitive function was measured using the Montreal Cognitive Assessment Scale and statistical analysis was conducted based on the relevant data. RESULTS: The results showed that cognitive impairment was higher in peritoneal dialysis patients than in non-dialysis subjects. Age and educational background were single factors that affected cognitive function, which was more likely to be impaired at a higher age level and/or a lower educational level. CONCLUSION: Cognitive function can be impaired by peritoneal dialysis, and age and education levels are influencing factors.


Assuntos
Disfunção Cognitiva , Falência Renal Crônica , Diálise Peritoneal , Cognição , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Humanos , Falência Renal Crônica/diagnóstico , Diálise Peritoneal/métodos
14.
Anal Chem ; 83(12): 4930-5, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21561110

RESUMO

In this paper, we present an electrochemically driven large amplitude pH alteration method based on a serial electrolytic cell involving a hydrogen permeable bifacial working electrode such as Pd thin foil. The method allows solution pH to be changed periodically up to ±4~5 units without additional alteration of concentration and/or composition of the system. Application to the acid-base driven cyclic denaturation and renaturation of 290 bp DNA fragments is successfully demonstrated with in situ real-time UV spectroscopic characterization. Electrophoretic analysis confirms that the denaturation and renaturation processes are reversible without degradation of the DNA. The serial electrolytic cell based electrochemical pH alteration method presented in this work would promote investigations of a wide variety of potential-dependent processes and techniques.


Assuntos
Ácidos/química , DNA/química , Técnicas Eletroquímicas/métodos , Biocatálise , Eletrodos , Enzimas/metabolismo , Concentração de Íons de Hidrogênio , Desnaturação de Ácido Nucleico , Renaturação de Ácido Nucleico , Paládio/química
15.
Cytokine ; 56(3): 648-55, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21962931

RESUMO

Cardiovascular and musculoskeletal deconditioning occurring in long-term spaceflight requires new strategies to counteract these adverse effects. We previously reported that a short-arm centrifuge produced artificial gravity (AG), together with ergometer, has an approving effect on promoting cardiovascular function. The current study sought to investigate whether the cardiac and cerebrovascular functions were maintained and improved using a strategy of AG combined with exercise training on cardiovascular function during 4-day head-down bed rest (HDBR). Twelve healthy male subjects were assigned to a control group (CONT, n=6) and an AG combined with ergometric exercise training group (CM, n=6). Simultaneously, cardiac pumping and systolic functions, cerebral blood flow were measured before, during, and after HDBR. The results showed that AG combined with ergometric exercise caused an increase trend of number of tolerance, however, there was no significant difference between the two groups. After 4-day HDBR in the CONT group, heart rate increased significantly (59±6 vs 66±7 beats/min), while stroke volume (98±12 vs 68±13 mL) and cardiac output (6±1 vs 4±1 L/min) decreased significantly (p<0.05). All subjects had similar drops on cerebral vascular function. Volume regulating hormone aldosterone increased in both groups (by 119.9% in CONT group and 112.8% in the CM group), but only in the CONT group there were a significant changes (p<0.05). Angiotensin II was significantly increased by 140.5% after 4-day HDBR in the CONT group (p<0.05), while no significant changes were observed in the CM group. These results indicated that artificial gravity with ergometric exercise successfully eliminated changes induced by simulated weightlessness in heart rate, volume regulating hormones, and cardiac pumping function and partially maintained cardiac systolic function. Hence, a daily 1h alternating +1.0 and +2.0 Gz with 40 W exercise training appear to be an effective countermeasure against cardiac deconditioning.


Assuntos
Repouso em Cama , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Ergometria , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Coração/fisiologia , Aldosterona/sangue , Angiotensina II/sangue , Artérias/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Peso Corporal/fisiologia , Circulação Cerebrovascular/fisiologia , Exercício Físico/fisiologia , Testes de Função Cardíaca , Frequência Cardíaca/fisiologia , Humanos , Masculino , Intolerância Ortostática/sangue , Intolerância Ortostática/fisiopatologia , Sístole/fisiologia , Fatores de Tempo , Adulto Jovem
16.
Eur J Appl Physiol ; 111(9): 2315-25, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21336952

RESUMO

We have shown previously that combined short-arm centrifuge and aerobic exercise training preserved several physiologically important cardiovascular functions in humans. We hypothesized that artificial gravity (AG) and exercise is effective to prevent changes of physical problems during head-down bed rest (HDBR). To test this hypothesis, 12 healthy male subjects had undergone 4 days of 6° HDBR. Six of them were exposed to AG of an alternating 2-min intervals of +1.0 and +2.0 Gz at foot level for 30 min twice per day with ergometric exercise of 40 W as a countermeasure during bed rest (CM group), while the remaining six served as untreated controls (no-CM group). Before and after 4 days of bed rest, leg venous hemodynamics was assessed by venous occlusion plethysmography and autonomic cardiovascular control estimated by power spectral analysis of blood pressure and heart rate. Further, orthostatic tolerance was evaluated by a 75° head-up tilt test and physical working capacity was surveyed by near maximal physical working capacity test before and after bed rest. The data showed that combined centrifuge and exercise applied twice daily for a total of 60 min during 4 days of HDBR prevented (a) a decrease in working capacity, (b) autonomic dysfunction (a decrease in the activity of parasympathetic cardiac innervation) and (c) an increase in leg venous flow resistance. The combination of a 30 min alternating of +1.0 and +2.0 Gz for twice per day of AG with 40 W ergometric exercise may offer a promising countermeasure to short duration simulated microgravity.


Assuntos
Repouso em Cama , Descondicionamento Cardiovascular , Exercício Físico/fisiologia , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça , Contramedidas de Ausência de Peso , Adulto , Repouso em Cama/efeitos adversos , Pressão Sanguínea/fisiologia , Descondicionamento Cardiovascular/fisiologia , Teste de Esforço , Gravidade Alterada/efeitos adversos , Decúbito Inclinado com Rebaixamento da Cabeça/efeitos adversos , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Frequência Cardíaca/fisiologia , Hemodinâmica , Humanos , Masculino , Fatores de Tempo , Simulação de Ausência de Peso/métodos , Adulto Jovem
17.
Zhonghua Yi Xue Za Zhi ; 91(1): 20-2, 2011 Jan 04.
Artigo em Chinês | MEDLINE | ID: mdl-21418956

RESUMO

OBJECTIVE: To analyze the computed tomographic (CT) features of invasive pulmonary fungal infections (IPFI) and evaluate the value of CT-guided percutaneous biopsy. METHODS: Seventeen IPFI cases diagnosed by CT-guided percutaneous biopsy were recruited. The distribution, extent, density and size of IPFI were analyzed in correlation with the final diagnosis retrospectively. And the relationship with the causative factor of mycosis was also assessed. RESULTS: (1) Candida albicans (n = 7) and cryptococcosis & aspergillus (n = 5) were identified. (2) It showed segmental on lobar consolidation within lung field (n = 6), mixture of patterns and nodule (n = 4) and mass (n = 7). (3) The overall diagnostic accuracy of fiberoptic bronchoscopy examination was 35.3%. (4) The incidence of complicated pneumothorax was 11.8% (2/17). These cases were self-limited without any special treatment. CONCLUSION: The CT findings of PFI are too complex to be easily distinguished from other diseases. And the CT-guided percutaneous is a safe and effective procedure.


Assuntos
Biópsia por Agulha/métodos , Pneumopatias Fúngicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Med Sci Monit ; 16(12): CR575-83, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21119574

RESUMO

BACKGROUND: Musculoskeletal and cardiovascular deconditioning occurring in long-term spaceflight gives rise to the needs to develop new strategies to counteract these adverse effects. Short-arm centrifuge combined with ergometer has been proposed as a strategy to counteract adverse effects of microgravity. This study sought to investigate whether the combination of short-arm centrifuge and aerobic exercise training have advantages over short-arm centrifuge or aerobic exercise training alone. MATERIAL/METHODS: One week training was conducted by 24 healthy men. They were randomly divided into 3 groups: (1) short-arm centrifuge training, (2) aerobic exercise training, 40 W, and (3) combined short-arm centrifuge and aerobic exercise training. Before and after training, the cardiac pump function represented by stroke volume, cardiac output, left ventricular ejection time, and total peripheral resistance was evaluated. Variability of heart rate and systolic blood pressure were determined by spectral analysis. Physical working capacity was surveyed by near maximal physical working capacity test. RESULTS: The 1-week combined short-arm centrifuge and aerobic exercise training remarkably ameliorated the cardiac pump function and enhanced vasomotor sympathetic nerve modulation and improved physical working capacity by 10.9% (P<.05, n=8). In contrast, neither the short-arm centrifuge nor the aerobic exercise group showed improvements in these functions. CONCLUSIONS: These results demonstrate that combined short-arm centrifuge and aerobic exercise training has advantages over short-arm centrifuge or aerobic exercise training alone in influencing several physiologically important cardiovascular functions in humans. The combination of short-arm centrifuge and aerobic exercise offers a promising countermeasure to microgravity.


Assuntos
Exercício Físico/fisiologia , Hipogravidade , Análise de Variância , Pressão Sanguínea , Débito Cardíaco , Centrifugação , Frequência Cardíaca , Humanos , Masculino , Avaliação da Capacidade de Trabalho , Adulto Jovem
19.
J Cell Biochem ; 107(2): 357-63, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19306295

RESUMO

Alterations of nitric oxide contribute to post-flight orthostatic intolerance. The aim of this study was to investigate the changes of inducible nitric oxide synthase (iNOS) and the mechanisms underlying regulation of iNOS by simulated microgravity in human umbilical vein endothelial cells (HUVECs). Clinorotation, a simulated-model of microgravity, increased iNOS expression and promoter activity in HUVECs. The transactivations of NF-kappaB and AP-1 were suppressed by 24 h clinorotation. A key role for AP-1, but not NF-kappaB in the regulation of iNOS was shown. (1) PDTC, a NF-kappaB inhibitor, had no effect on clinorotation upregulation of iNOS. (2) SP600125, a JNK-specific inhibitor, which resulted in inhibition of AP-1 activity, enhanced the iNOS expression and promoter activity in clinorotation. (3) Overexpression of AP-1 remarkably attenuated the upregulation effect of clinorotation. These findings indicate that clinorotation upregulates iNOS in HUVECs by a mechanism dependent on suppression of AP-1, but not NF-kappaB. These results support a key role for AP-1 in the signaling of postflight orthostatic intolerance.


Assuntos
Células Endoteliais/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Intolerância Ortostática/fisiopatologia , Rotação/efeitos adversos , Fator de Transcrição AP-1/metabolismo , Western Blotting , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Humanos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Voo Espacial , Ativação Transcricional , Veias Umbilicais , Regulação para Cima , Simulação de Ausência de Peso
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA