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1.
Zhonghua Yi Shi Za Zhi ; 53(4): 195-200, 2023 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-37726997

RESUMO

Some information and records about musk (She, ) and river deer (Zhang, /) can be found in local chronicles or documents in Guizhou. They were taken as the same species in terms of a medicinal animal. The records for their living areas in Guizhou were neither clear nor in detail in the Ming Dynasty, but were specific in the Qing Dynasty and more concise in the period of the Republic of China. The living areas for musk and river deer reduced from the Ming Dynasty to the Republic of China. Such change was believed to be the result of the natural environment and the social factors as well, such as the reclamation of mountain areas in Guizhou, the reduction of forests, and the demand and resulting exorbitant prices that led to excessive hunting.


Assuntos
Cervos , Animais , Feminino , Rios , Ácidos Graxos Monoinsaturados , Taiwan
3.
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(7): 1188-1193, 2021 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814529

RESUMO

Objective: To explore the association between sleep duration, sleep quality and the prevalence of hypertension in the elderly aged 65 years and above. Methods: This study was conducted among the elderly in communities in Yiwu, China from April to July, 2019, and participants were recruited through physical examination in the hospital. Face-to-face interview was performed to obtain basic information. Sleep duration and sleep quality were evaluated by Pittsburgh Sleep Quality Index (PSQI). Associations between sleep duration, sleep quality and hypertension were evaluated by multivariate logistic regression analysis. Results: A total of 3 169 elderly persons, aged ≥65 years old, were included in the study. The overall prevalence of hypertension was 50.8%. The elderly with very poor sleep quality and short sleep duration accounted for 22.4% and 28.5%, respectively. After adjusting for demographic characteristics, socioeconomic status, lifestyle and health status, the OR of hypertension for the elderly with very poor sleep quality was 1.42 (95%CI: 1.12-1.80) compared with those with very good sleep quality. Compared with the elderly with sleep duration of 6-7 h a night, the OR of hypertension for those with sleep duration <6 h was 1.37 (95%CI: 1.15-1.65). As the sleep quality decreased, the risk for hypertension increased. An U-shaped association was found between sleep duration and risk of hypertension. Subgroup analyses showed that this association existed in both men and women, but only significant in the elderly aged <75 years. Conclusion: Poor sleep quality and short sleep duration were associated with risk for hypertension in the elderly.


Assuntos
Hipertensão , Transtornos do Sono-Vigília , Idoso , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Prevalência , Fatores de Risco , Sono , Transtornos do Sono-Vigília/epidemiologia
5.
Zhonghua Er Ke Za Zhi ; 58(5): 387-391, 2020 May 02.
Artigo em Chinês | MEDLINE | ID: mdl-32392954

RESUMO

Objective: To investigate the current situation of human milk (HM) feeding in hospitalized very low and extremely low birth weight infants. Methods: The study retrospectively extracted the data of 601 infants with birth weight <1 500 g, and admitted within 24 hours after birth to the Neonatal Intensive Care Unit of Nanjing Maternity and Child Health Care Hospital from January 2016 to December 2018. The infants were grouped into exclusive mother's-own-milk (MOM) group, donor human milk (DHM) group (partial or none MOM), and mixed (HM and formula) feeding group according to the feeding strategy. Qualitative and quantitative variables in the three groups were compared with One-way ANOVA, Kruskal-Wallis test, Chi-square test or Fisher exact test. Kappa and McNemar test were used for consistency testing. Results: Among the 601 infants (309 boys and 292 girls), 6 (1.0%) infants had never been fed with MOM. The gestational age and birth weight were (29.3±1.9) weeks and 1 260(1 115, 1 400) g in 601 infants. A total of 8 (1.3%) infants were grouped into MOM group, 542 (90.2%) were grouped into DHM group, and 51 (8.5%) were grouped into mixed feeding group. The percentage of enteral feedings with MOM in the stage of hospitalization 1-7 d, 8-14 d and 15-28 d were 73.6% (42.9%, 86.7%), 97.5% (78.6%, 100.0%) and 99.3% (93.0%, 100.0%), respectively (H=414.95, P<0.01), and the pairwise comparison suggested that the stage of hospitalization 1-7 d was the lowest (adjusted both P<0.05). The average weight adjusted daily dose of MOM were 9.7 (4.3, 18.2), 59.1 (26.5, 93.5) and 116.0 (60.3, 142.6) ml/(kg·d) in the stage of hospitalization 1-7 d, 8-14 d and 15-28 d, respectively (H=759.75, P<0.01), and the pairwise comparison suggested that the stage of hospitalization 1-7 d was the lowest (adjusted both P<0.05). The weight adjusted daily dose of MOM in exclusive MOM group, DHM and Mixed feeding group were 95.2 (40.0, 117.2), 82.9(53.6, 103.1) and 55.7 (16.6, 97.5) ml/(kg·d), respectively (H=10.78, P=0.005).Additionally, the percentage and weight adjusted daily dose of MOM showed a general consistency of 0.703 (P>0.05, Kappa=0.408). Conclusions: The rate of exclusive MOM feeding is low, especially during the first 7 days of hospitalization. The percentage of total enteral feedings with MOM and the average weight adjusted daily dose of MOM can well evaluate the situation of HM feeding during hospitalization quantitively.


Assuntos
Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido de muito Baixo Peso , Leite Humano , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Gravidez , Estudos Retrospectivos
6.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 37(12): 903-906, 2019 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-31937029

RESUMO

Objective: To explore the difference of personality characteristics of physicians, nurses, medical skills and administrative personnel in a general hospital and its influence on job burnout. Methods: Employee entered the hospital before 2018 were enrolled in the current study and the position was classified as physicians, nurses, medical technician and administrative staff. Minnesota Multiphasic Personality Inventory (MMPI) was completed by the employee at the time of entering the hospital. Status of job burnout was assessed in 2018 using the Maslach Burnout Inventory-General Survey (MBI-GS) . Results: Physicians have a higher rate of paranoia than others (P<0.05) , and administrative staff and medical technician have a slightly higher score than the other two categories of people (P<0.05) , and administrators lie at a higher rate than others (P<0.05) . Further analysis found that personality traits did not have a significant association with job burnout at the time of entry. Conclusion: The administrative and medical staff is slightly more irritable, the administrative staff lying slightly higher score, the staff after the entry of job burnout is not affected by the personality characteristics of the onboarding.


Assuntos
Esgotamento Profissional/epidemiologia , Disparidades nos Níveis de Saúde , MMPI , Recursos Humanos em Hospital/psicologia , Hospitais Gerais , Humanos , Recursos Humanos em Hospital/estatística & dados numéricos
7.
Zhonghua Er Ke Za Zhi ; 55(8): 635-637, 2017 Aug 02.
Artigo em Chinês | MEDLINE | ID: mdl-28822444
8.
Environ Monit Assess ; 189(8): 411, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28735434

RESUMO

Assessment of groundwater quality plays a significant role in the utilization of the scarce water resources globally and especially in arid regions. The increasing abstraction together with man-made contamination and seawater intrusion have strongly affected groundwater quality in the Arabia Peninsula, exemplified by the investigation given here from the United Arab Emirates, where the groundwater is seldom reviewed and assessed. In the aim of assessing current groundwater quality, we here present a comparison of chemical data linked to aquifers types. The results reveal that most of the investigated groundwater is not suitable for drinking, household, and agricultural purposes following the WHO permissible limits. Aquifer composition and climate have vital control on the water quality, with the carbonate aquifers contain the least potable water compared to the ophiolites and Quaternary clastics. Seawater intrusion along coastal regions has deteriorated the water quality and the phenomenon may become more intensive with future warming climate and rising sea level.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Poluentes Químicos da Água/análise , Agricultura , Água Potável , Água do Mar , Qualidade da Água/normas , Recursos Hídricos/provisão & distribuição
9.
Genet Mol Res ; 14(4): 18675-86, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26782517

RESUMO

The swimming crab, Portunus trituberculatus, is an important marine animal and is widely cultured in China. In the present study, suppression subtractive hybridization was applied to identify the differentially expressed genes in the ovaries of mature and immature P. trituberculatus. One hundred and seventy six expressed sequence tag (ESTs) were identified, of which 100 were down-regulated, and 76 up-regulated. BLAST analysis identified 51 unigenes, of which 27 were down-regulated, and 24 up-regulated. Quantitative real-time reverse transcriptase polymerase chain reaction results indicated that the SSH technique is valuable in screening genes related to ovarian development. Genes identified in this study encoded proteins corresponding to a wide range of functions and included immune response protein, transcription initiation factor, metabolic proteins, chromosome, histone h3, ovarian development-related protein, and vitellogenin. In addition, 64 metabolic pathways were annotated in differentially expressed ESTs by using the Kyoto Encyclopedia of Genes and Genomes pathway. Four annotated pathways (oxidative phosphorylation, carbon metabolism, fatty acid degradation, and protein digestion and absorption) appeared to be involved in ovarian development. In ontology analysis, 5.83% of the cellular process genes in reverse subtraction cDNA library are involved in reproduction, and 5.88% involved in developmental process. In up-regulated genes, myosin II-expressed polehole-like protein; histone h3; ovigerous-hair stripping substance; peritrophin 48; and ovarian development-related protein appeared to be involved in ovarian development. Identification of differentially expressed genes in the mature and immature ovary of the swimming crab provides new insights for further studies on the mechanism underlying ovarian development in this species.


Assuntos
Crustáceos/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Ovário/embriologia , Animais , Biologia Computacional/métodos , Etiquetas de Sequências Expressas , Feminino , Biblioteca Gênica , Redes e Vias Metabólicas , Ovário/metabolismo , Técnicas de Hibridização Subtrativa
10.
Environ Monit Assess ; 186(10): 6157-67, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24903925

RESUMO

Groundwater is the most valuable resource in arid regions, and recognizing radiological criteria among other water quality parameters is essential for sustainable use. In the investigation presented here, gross-α and gross-ß were measured in groundwater samples collected in the south-eastern Arabian Peninsula, 67 wells in Unite Arab Emirates (UAE), as well as two wells and one spring in Oman. The results show a wide gross-α and gross-ß activities range in the groundwater samples that vary at 0.01∼19.5 Bq/l and 0.13∼6.6 Bq/l, respectively. The data show gross-ß and gross-α values below the WHO permissible limits for drinking water in the majority of the investigated samples except those in region 4 (Jabel Hafit and surroundings). No correlation between groundwater pH and the gross-α and gross-ß, while high temperatures probably enhance leaching of radionuclides from the aquifer body and thereby increase the radioactivity in the groundwater. This conclusion is also supported by the positive correlation between radioactivity and amount of total dissolved solid. Particular water purification technology and environmental impact assessments are essential for sustainable and secure use of the groundwater in regions that show radioactivity values far above the WHO permissible limit for drinking water.


Assuntos
Água Subterrânea/química , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Água Potável/química , Omã , Radioatividade , Radioisótopos/análise , Poluentes Radioativos da Água/normas
11.
Appl Radiat Isot ; 82: 223-31, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24056000

RESUMO

The semi-enclosed Baltic Sea represents a vital economic and recreational resource for more than 90 million people inhabiting its coasts. Extensive contamination of this sea by a variety of anthropogenic pollutants has raised the concern of the people in the region. Quantifying seawater inflow is crucial for estimating potential environmental risks as well as to find the best remedial strategy. We present here a model to estimate water inflow from the North Sea to the Baltic Sea by utilizing ¹²9I as a tracer. The results predicted inflow range of 230-450 km³/y with best fit value around 330 km³/y from the North Sea to the Baltic Sea during 1980-1999. Despite limited time series data on ¹²9I, the model presented here demonstrates a new management tool for the Baltic Sea to calculate inflow water compared to conventional methods (such as salinity, temperature and hydrographic models).


Assuntos
Hidrologia/métodos , Radioisótopos do Iodo/análise , Água do Mar/análise , Países Bálticos , Simulação por Computador , Humanos , Hidrologia/estatística & dados numéricos , Modelos Teóricos , Poluentes Radioativos da Água/análise
12.
Obes Rev ; 12(7): 525-42, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21438992

RESUMO

This report describes the association between birth weight (BW) and obesity. Screening of 478 citations from five electronic databases resulted in the inclusion of 33 studies, most of medium quality. The meta-analysis included 20 of these published studies. The 13 remaining articles did not provide sufficient dichotomous data and were systematically reviewed, revealing results consistent with the meta-analysis. Our results revealed that high BW (>4000 g) was associated with increased risk of obesity (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.91-2.24) compared with subjects with BW ≤ 4000 g. Low BW (<2500 g) was associated with decreased risk of obesity (OR, 0.61; 95% CI, 0.46-0.80) compared with subjects with BW ≥ 2500 g. However, when two studies exhibited selection bias were removed, the results indicated no significant association between low BW and obesity (OR, 0.77; 95% CI, 0.58-1.04). Sensitivity analyses showed that differences in the study design, sample size and quality grade of the study had an effect on the low BW/obesity association, which low BW was not associated with the risk of obesity in cohort studies, studies with large sample sizes and studies with high quality grades. Pooled results were similar when normal birth weight (2500-4000 g) was used as the reference category. Subgroup analyses based on different growth and developmental stages (pre-school children, school children and adolescents) also revealed that high BW was associated with increased risk of obesity from childhood to early adulthood. No significant evidence of publication bias was present. These results suggest that high BW is associated with increased risk of obesity and may serve as a mediator between prenatal influences and later disease risk.


Assuntos
Peso ao Nascer , Obesidade/epidemiologia , Adolescente , Criança , Pré-Escolar , Intervalos de Confiança , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Razão de Chances , Fatores de Risco
14.
Obes Rev ; 11(9): 656-70, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19780990

RESUMO

We performed a systematic review describing obesity/intelligent quotient (IQ) association, particularly childhood IQ in relation to adulthood obesity. After screening 883 citations from five electronic databases, we included 26 studies, most of medium quality. The weighted mean difference (WMD) of the full IQ (FIQ)/obesity association in the pre-school children was -15.1 (P > 0.05). Compared with controls, the WMD of FIQ and performance IQ of obese children were -2.8 and -10.0, respectively (P < 0.05), and the WMD of verbal IQ was -7.01 (P > 0.05). With increasing obesity, the FIQ in pre-school children declined, with a significant difference for severely obese children and FIQ. In pubertal children, a slightly different effect of FIQ and obesity emerged. Two studies reported an inverse FIQ/obesity association in adults, but it was non-significant after adjusting for educational attainment. Four papers found that childhood FIQ was inversely associated with adult body mass index, but after adjusting for education, became null. Overall there was an inverse FIQ/obesity association, except in pre-school children. However, after adjusting for educational attainment, FIQ/obesity association was not significantly different. A lower FIQ in childhood was associated with obesity in later adulthood perhaps with educational level mediating the persistence of obesity in later life.


Assuntos
Inteligência/fisiologia , Obesidade/psicologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Escolaridade , Feminino , Humanos , Testes de Inteligência , Masculino
15.
Sheng Li Xue Bao ; 53(2): 123-7, 2001 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-11471211

RESUMO

To examine the effect of simulated weightlessness on inducible HSP70 expression in the heart and vessel tissues of rats, a tail-suspension rat model was used to simulate weightlessness. HSP72 mRNA and HSP70 expression in heart and vessel tissues of both simulated weightless and control rats exposed to heat stress (ambient temperature, Ta = 43 degrees C) and recovered at Ta of 25 degrees C for 1 h (CON-H1, SUS-H1) or 2 h (CON-H2, SUS-H2) were analyzed using Northern blot and Western blot. The expression of HSP72 mRNA in the myocardium significantly decreased in SUS-H2, as compared with that of CON-H2 rats. The amount of HSP72 in the myocardium tended to decrease in both SUS-H1 and SUS-H2 groups, as compared with the corresponding control groups, but the differences were not statistically significant. The levels of inducible HSP70 expression in the vessels were related with their anatomical locations, for that the expression of both HSP72 mRNA and HSP72 significantly increased in basilar arteries, whereas it showed a slight decline in femoral arteries. The blunted HSP70 expression in myocardium suggests that simulated weightlessness may induce myocardial changes similar to those in aging. However, the HSP70 expression changes in arteries are in accord with the trend of differential adaptation changes in vessels to simulated weightlessness.


Assuntos
Vasos Sanguíneos/metabolismo , Proteínas de Choque Térmico HSP70/biossíntese , Miocárdio/metabolismo , Simulação de Ausência de Peso , Animais , Proteínas de Choque Térmico HSP70/genética , Temperatura Alta , Masculino , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley
16.
Aviat Space Environ Med ; 72(6): 567-75, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11396563

RESUMO

Studies on the mechanisms of cardiovascular dysfunction after space-flight are important to illustrate the cardiovascular effect of microgravity and develop appropriate multi-system countermeasures for future long-duration spaceflights. Over the past 10 yr, we have systematically studied the adaptational changes in structure and function of both the heart and vessels, using the tail-suspension rat model to simulate microgravity effects. Our results indicate that simulated microgravity induced atrophic changes and reduced contractility of the heart muscle, and upward- and downward-regulation in structure, function, and innervation state of vessels in the brain and hind body of the rat. In addition, more recent advances in relevant ground-based and space-flight studies from different laboratories have also been reviewed. Based on these studies, it has been speculated that, in addition to hypovolemia, the microgravity-induced adaptational changes in the structure and function of the two main effectors of the cardiovascular system, i.e., the arterial smooth muscle and the cardiac muscle, might be among the most important mechanisms responsible for postflight cardiovascular dysfunction and orthostatic intolerance. In this paper we will review the available evidence with comments.


Assuntos
Adaptação Fisiológica , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Modelos Animais de Doenças , Modelos Cardiovasculares , Músculo Liso Vascular/fisiopatologia , Contração Miocárdica/fisiologia , Miocárdio , Voo Espacial , Simulação de Ausência de Peso/efeitos adversos , Animais , Atrofia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Regulação para Baixo , Elevação dos Membros Posteriores , Humanos , Hipotensão Ortostática/etiologia , Hipotensão Ortostática/metabolismo , Hipotensão Ortostática/patologia , Hipotensão Ortostática/fisiopatologia , Hipovolemia/etiologia , Hipovolemia/metabolismo , Hipovolemia/patologia , Hipovolemia/fisiopatologia , Músculo Liso Vascular/patologia , Miocárdio/patologia , Ratos , Regulação para Cima
17.
Biochemistry ; 40(8): 2623-31, 2001 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-11327886

RESUMO

The primary structure of the COOH-terminal region of troponin I (TnI) is highly conserved among the cardiac, slow, and fast skeletal muscle TnI isoforms and across species. Although no binding site for the other thin filament proteins is found at the COOH terminus of TnI, truncations of the last 19-23 amino acid residues reduce the activity of TnI in the inhibition of actomyosin ATPase and result in cardiac muscle malfunction. We have developed a specific monoclonal antibody (mAb), TnI-1, against the conserved COOH terminus of TnI. Using this mAb, isolation of the troponin complex by immunoaffinity chromatography from muscle homogenate and immunofluorescence microscopic staining of myofibrils indicate that the COOH terminus of TnI forms an exposed structure in the muscle thin filament. Binding of this mAb to the COOH terminus of cardiac TnI induced extensive conformational changes in the protein, suggesting an allosteric role of this region in the functional integrity of troponin. In the absence of Ca2+, the binding of troponin C and troponin T to TnI had very little effect on the conformation of the COOH terminus of TnI as indicated by the unaffected mAb affinity for the TnI-1 epitope. However, Ca2+ significantly increased the accessibility of the TnI-1 epitope on TnI in the presence of troponin C and troponin T. The results provide evidence that the COOH terminus is an essential structure in TnI and participates in the allosteric switch during Ca2+ activation of contraction.


Assuntos
Cálcio/química , Sequência Conservada , Fragmentos de Peptídeos/metabolismo , Troponina I/metabolismo , Sítio Alostérico/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/metabolismo , Afinidade de Anticorpos , Galinhas , Sequência Conservada/imunologia , Feminino , Humanos , Hibridomas , Substâncias Macromoleculares , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Conformação Proteica , Estrutura Terciária de Proteína , Codorniz , Ratos , Salmo salar , Troponina C/metabolismo , Troponina I/química , Troponina I/imunologia , Troponina T/metabolismo , Xenopus laevis
18.
J Biol Chem ; 276(19): 15753-60, 2001 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-11278823

RESUMO

In a tail suspension rat model, we investigated changes in myofilament protein during cardiac adaptation in simulated microgravity. Contractile force and velocity of cardiac muscle were decreased in the tail suspension rats as compared with the control. Ca(2+)-dependent actomyosin ATPase activity was also decreased; however, sensitivity of cardiac muscle to Ca(2+) activation was unchanged. There was no change in expression of myosin heavy chain, tropomyosin, troponin T, or troponin I isoforms in hearts of tail suspension rats. A novel finding is a fragment of cardiac troponin I (cTnI) that had increased amounts in the heart of tail suspension rats. Binding of this cTnI fragment by a monoclonal antibody that specifically recognizes the COOH terminus indicates an intact COOH terminus. NH(2)-terminal sequence analysis of the cTnI fragment revealed truncations primarily of amino acids 1-26 and 1-27 and smaller amounts of 1-30, including Ser(23) and Ser(24), which are substrates of protein kinase A phosphorylation. This cTnI fragment is present in normal cardiac muscle and incorporated into myofibrils, indicating a role in regulating contractility. This proteolytic modification of cTnI up-regulated during simulated microgravity suggests a potential role of the NH(2)-terminal segment of cTnI in functional adaptations of cardiac muscle.


Assuntos
Regulação da Expressão Gênica , Músculos Papilares/fisiologia , Troponina I/genética , Troponina I/fisiologia , Simulação de Ausência de Peso , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Estimulação Elétrica , Ventrículos do Coração , Elevação dos Membros Posteriores , Técnicas In Vitro , Masculino , Dados de Sequência Molecular , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Miofibrilas/fisiologia , Cadeias Pesadas de Miosina/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Serina , Troponina I/química
19.
Space Med Med Eng (Beijing) ; 14(6): 405-9, 2001 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-11887893

RESUMO

Objective. To observe and compare the effect of daily standing of rats for different durations in alleviating the depression of myocardial contractility induced by simulated weightlessness. Method. Fifty male Sprague-Dawley rats were randomly assigned to five groups: simultaneous control (CON), four-week tail-suspension (SUS), SUS plus daily 1 h standing (STD1), SUS plus daily 2 h standing (STD2) and SUS plus daily 4 h standing (STD4). Four weeks later, wet weights of the left soleus, testis and adrenal gland were measured, and the isometric contractile tension and its time parameters of isolated perfused papillary muscles from rats of various groups were examined. Result. Compared with CON, the wet weights of testis in different treatment groups decreased significantly (P<0.05). The wet weight of soleus in SUS decreased by 58.9% (P<0.01); but in STD1, STD2 and STD4, decreased by 38.5%, 24.0% and 11.0% (P<0.01, or P<0.05) respectively. The relative protections were 34.7%, 59.2% and 81.4% (P<0.01) respectively. In SUS group, developed tension (DT), peak rate of tension rise (+dT/dtmax) and peak rate of tension fall (-dT/dtmax) decreased by 32.2%, 29.2% and 30.7% (P<0.05), and time to peak rate of tension rise (TPP) and time to peak tension (TPT) prolonged by 21.2% and 11.0% (P<0.05), respectively. Whereas in STD1, STD2 and STD4, all the parameters reflecting myocardial contractility (like DT, + dT/dtmax, -dT/dtmax and TPP), did not show any significant change as compared with those of CON. However, being an exception, TPT still showed obvious prolongation (P<0.05) in STD1. Conclusion. Daily 1 h standing could prevent depression of myocardial contractility in rat induced by medium-term simulated weightlessness. However, with respect to prevention of atrophic changes in soleus muscle and testis, daily standing for 1 h, 2 h, or 4 h was only partially effective and even totally devoid of any effect, respectively.


Assuntos
Músculo Esquelético/anatomia & histologia , Atrofia Muscular/prevenção & controle , Contração Miocárdica/fisiologia , Testículo/anatomia & histologia , Contramedidas de Ausência de Peso , Simulação de Ausência de Peso/efeitos adversos , Animais , Elevação dos Membros Posteriores/efeitos adversos , Masculino , Atrofia Muscular/etiologia , Atrofia Muscular/fisiopatologia , Tamanho do Órgão , Músculos Papilares/fisiopatologia , Postura/fisiologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
20.
Space Med Med Eng (Beijing) ; 14(3): 172-6, 2001 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-11892734

RESUMO

Objective. To observe the transition time of soleus I (TnI) isoforms and to elucidate the relationship between soleus TnI transition and atrophy; and to analyze the time course between testis atrophy and soleus atrophy. Method. Eight groups of male rats were suspended for 3, 4, 5, 7, 14, 21, 28 and 42 d, respectively. Besides, three groups of female rats were suspended for 3, 4 and 5 d respectively. Wet and relative weights (wet weight/body weight) of testis and soleus were measured. The expression of TnI was observed by Western blot. Result. The relative weight of soleus of tail-suspended male rats decreased significantly after 4 d of suspension as compared with control. The degree of rats soleus atrophy in the first 14 d of suspension was greater than that after 14 d. The relative weight of testis showed the same change as that of soleus. There was no significant change in the relative weight of soleus in 4 d of tail-suspended female rats. The significant decrease in the relative weight of tail-suspended female rats began on the 5th day. The Western blot showed that the transition from slow skeletal TnI (ssTnI) to fast skeletal TnI (fsTnI) in the soleus occurred in 14 d of tail-suspension. Conclusion. The overt atrophy of tail-suspended male rats occurs on the 4th day. The soleus TnI transition from ssTnI to fsTnI is on the 14th day. It is suggested that the TnI is not the sensitive protein to gravity. The overt atrophy of female tail-suspended rats occurs at the 5th day. This indicated that the decrease in testosterone level may accelerate the atrophy of the soleus.


Assuntos
Músculo Esquelético/metabolismo , Atrofia Muscular/fisiopatologia , Testículo/fisiopatologia , Troponina I/metabolismo , Simulação de Ausência de Peso/efeitos adversos , Animais , Feminino , Elevação dos Membros Posteriores , Masculino , Músculo Esquelético/fisiopatologia , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Isoformas de Proteínas , Ratos , Testosterona/metabolismo
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