Effects of different altitudes on cardiac hemodynamics and electrocardiogram of healthy male adults / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To detect the changes of cardiovascular system at different altitudes, so as to prevent and predict the susceptibility to acute mountain sickness.</p><p><b>METHODS</b>The test was performed with noninvasive cardiovascular monitor and electrocardiogram in healthy male Chinese members of the 25th and 26th expeditions to the antarctic kunlun station at different altitudes (40 m, 3 650 m and 4 300 m).</p><p><b>RESULTS</b>Compared with 40 m, from 3 650 m to 4 300 m, heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), systemic vascular resistance (SVR), systemic vascular resistance index (SVRI) significantly increased (P < 0.05); cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke index (SI), velocity index (VI), acceleration index (ACI), left ventricular ejection time (LVET) significantly decreased (P < 0.05) and pre-ejection period(PEP) decreased with no significance (P > 0.05).</p><p><b>CONCLUSION</b>SVR significantly increased but contractile and blood-pumping function of left ventricular decreased inversely associated with the Q-Tc interval, as the altitude is increasing.</p>

Fat mass and fat free mass on ventilatory function in adults / 生理学报

This study is designed to probe for the effects of fat mass (FM) and fat free mass (FFM) on ventilatory function in adults. 1 307 healthy adults (372 males and 935 females) were selected from some localities of Heilongjiang province through random sampling by means of questionnaire and physical examination and measured for height, weight, waist to hip ratio (WHR), FM, FFM and ventilatory function. The data were analyzed by means of Pearson correlation analysis, independent-samples t test and multi-factors regression analysis. Regardless of sex, an independent positive correlation was found (P<0.001) between age and fat mass index (FMI). Regardless of sex, fat free mass index (FFMI) was found to be positively associated with forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF) and forced expiratory flow at 25% of forced vital capacity (FEF25%) (P<0.01), and FMI was significantly and negatively related to FVC, FEV1, FEF75% (P<0.05). In males FMI was significantly and negatively related to maximal mid-expiratory flow (MMEF) (P<0.05). Regardless of sex, the effect of FFMI on FVC was higher than that of FMI. For the males, the effect of FFMI on FVC was smaller than that of FMI, while the opposite was found in the females. Regardless of sex, FEF75% tended to decrease with increasing FMI, while FFMI was found to have no effects on FEF75%. MMEF tended to decrease with increasing FMI in the males, but no marked change was found in the females. The above results suggest that FM and FFM are independent factors influencing ventilatory function in adults. FM is negatively correlated with ventilatory function, but as a reflection of muscle mass, FFM is positively correlated with ventilatory function in adults. There is quantitative difference between the effects of FFM and FM on ventilatory function.

Relation between fat mass, fat free mass and ventilatory function in children and adolescents / 生理学报

The aim of the present study was to evaluate the relation between fat mass (FM), fat free mass (FFM) and ventilatory function in children and adolescents. 1 174 healthy children and adolescents (583 males and 591 females) aged 10-18 years were selected from Heilongjiang Province through random sampling by means of questionnaire and physical examination, and measured for height, weight, waist to hip ratio (WHR), FM, FFM and ventilatory function. The data were analyzed by means of independent-samples t test, Pearson correlation analysis and multi-factors regression analysis. Regardless of sex, an independent positive correlation was found (P<0.001) between age and FFM index (FFMI). FM index (FMI) correlated negatively with age in males (P<0.001), but positively with age in females (P<0.001). Regardless of sex, FFMI correlated positively with forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), forced expiratory flow at 25% of forced vital capacity (FEF25%), FEF50%, and maximal mid-expiratory flow (MMEF) (P<0.05), while negatively with FEV1/FVC (P<0.01). FFMI was correlated positively with FEF75% in males (P<0.05), but not correlated in females. In males, FMI correlated negatively with FEV1, FEV1/FVC, PEF, FEF25%, FEF50%, FEF75% and MMEF (P<0.05), but not correlated with FVC. No correlation was found between the ventilatory function indices and FMI in females. Except FEV1/FVC and FEF75% in males, the effect of FFMI in predicting ventilatory function was higher than FMI regardless of sex. Moreover, the predicting effect of FFMI was higher in males than that in females. Growth spurt of lung function occurred in the ages of 12-15 years in males, while in the ages of 12, 13 and 18 years in females. During the period of growth spurt of lung function, regardless of sex, the effect of FFMI in predicting the lung function was higher than that of age. In conclusion, regardless of sex, FFMI correlates positively with ventilatory function, as a reflection of muscle mass. The effect of FFM in predicting ventilatory function is higher in males than that in females. FM correlates negatively with ventilatory function in males, but not in females. The rapid growth of height and FFM are possibly the main reasons for growth spurt of lung function.

The relationship between body fat percentage, waist-hip ratio and pulmonary ventilatory function among the adult females in Heilongjiang, in 2008 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To examine the effect of body fat mass and fat distribution on pulmonary ventilatory function among the adult females.</p><p><b>METHODS</b>Based on the multistage cluster sampling principal, we selected 935 healthy adult females with ages of 19-81 years old in Heilongjiang province to conduct the study. Every 10-years old as a age group. Firstly obtain the basic situation through the questionnaire survey, and then measure the height, body weight, waistline, hip circumference, body composition and lung function. FVC, FEV1, PEF, FEF25%, FEF 50%, FEF 75% and MMEF were determined. This study also examined the relationships between percentage body fat (PBF), waist-hip ratio (WHR) and FVC, FEV1, PEF, FEF25%, FEF 50%, FEF 75%, MMEF.</p><p><b>RESULTS</b>PBF of subjects with ages of 19 - 29 years old and over 60 years old were (16.89 ± 5.34)% and (24.39 ± 6.83)%, WHR were 0.77 ± 0.05 and 0.88 ± 0.06, respectively. PBF and WHR tended to increase with age (F = 50.11, P value < 0.01). PBF obesity rates of subjects with ages of 19 - 29 years old and over 60 years old were 3.23% (7/217) and 43.75% (28/64), WHR obesity rates were 19.35% (42/217) and 85.94% (55/64) respectively. PBF obesity rate and WHR obesity rate tended to increase with age (χ(2) = 161.66, P value < 0.01; χ(2) = 159.61, P value < 0.01). PBF obesity groups compared with the normal groups, the former pulmonary ventilation function reduced significantly, of which FEF 50%, FEF 75% and MMEF decreased 2.61%, 19.44%, 10.28%, respectively. WHR obesity groups compared with the normal groups, the former pulmonary ventilation function reduced significantly, of which FEF 50%, FEF 75% and MMEF decreased 7.61%, 23.15%, 12.04%. After adjustment of age, height and body mass index (BMI), PBF was negatively correlated with FVC, FEV1, PEF and FEF25% (r values were -0.14, -0.14, -0.07, -0.07, respectively, all P value s < 0.05); WHR was negatively correlated with FEV1 (r value was -0.07, P value < 0.05) after adjustment of age, height and BMI.</p><p><b>CONCLUSION</b>PBF augmentation and abdominal obesity among adult females may be the risk factors of pulmonary function impairment.</p>

The relationship between percentage body fat, waist-hip ratio and cardiovascular function in the adult females of Heilongjiang province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the relationship between body fat mass and distribution and cardiovascular function in the adult females of Heilongjiang province.</p><p><b>METHODS</b>Based on the statistic variable random sampling principal, we selected 1903 healthy adult females with ages of 18 - 70 years old in Heilongjiang province to conduct the study. The height, body weight, waist, chest measurement and waist-hip ratio (WHR) were measured. Body components quota including fat weight, lean weight, percentage of body fat (PBF) were taken respectively; systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke index (SI), left cardiac work (LCW) and systemic vascular resistance (SVR) were determined.</p><p><b>RESULTS</b>The PBF and WHR increased with aging, and the PBF of those with ages of 18-, 30-, 40-, 50- and 60 - 70 year's old were (16.86 +/- 5.37)%, (18.43 +/- 4.89)%, (20.99 +/- 5.79)%, (23.47 +/- 5.74)% and (25.77 +/- 6.38)%, respectively (F = 154.46, P < 0.01); and the WHR were 0.77 +/- 0.05, 0.80 +/- 0.05, 0.83 +/- 0.05, 0.85 +/- 0.06 and 0.89 +/- 0.07, respectively (F = 229.84, P < 0.01). The HR, CO, CI, SBP, DBP and LCW were (75.45 +/- 0.35) bpm, (4.42 +/- 0.02) L/min, (2.78 +/- 0.01) L * min(-1) * m(-2), (114.94 +/- 0.40) mm Hg (1 mm Hg = 0.133 kPa), (64.90 +/- 0.28) mm Hg, (4.57 +/- 0.03) kg * m/m(2) respectively in normal PBF groups; whereas the HR, CO, CI, SBP, DBP and LCW in the PBF obesity groups were (77.42 +/- 0.88) bpm, (4.54 +/- 0.05) L/min, (2.88 +/- 0.03) L * min(-1) * m(-2), (120.55 +/- 1.00) mm Hg, (66.56 +/- 0.71) mm Hg and (4.86 +/- 0.07) kg * m/m(2), respectively, F values were 3.182, 9.173, 8.478, 13.497, 2.637, and 10.631, respectively (all P values < 0.05) after the adjustment of age, height and weight, PBF was positively correlated with HR, CO, CI, SI, SBP, DBP and LCW (r values were 0.06, 0.11, 0.10, 0.11 and 0.12, respectively, all P values < 0.05); WHR was positively correlated with CI, SI, SBP, DBP, LCW and SVR (r values were 0.14, 014, 0.19, 0.18, 0.10 and 0.12, respectively, all P values < 0.01) after the adjustment of age, height and weight.</p><p><b>CONCLUSION</b>PBF augmentation and abdominal obesity in females can result in cardiac dysfunction such as cardiac overload, CO increasing and blood pressure rising.</p>

Ultrasonic bone mineral density of calcaneus in 1 816 healthy subjects in Guangxi autonomous region / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the relationship between ultrasonic bone mineral density (BMD) of calcaneus and age, height, and body weight, and to establish the normal reference value for stiffness index (SI) of healthy subjects in Guangxi autonomous region and provide scientific foundation for the diagnosis and prevention of osteoporosis.</p><p><b>METHODS</b>SI of calcaneus in 1 816 healthy adults aged 11-90 years (775 men, 1 041 women) were measured with quantitative ultrasound. According to their ages, all the men and women were divided into 13 groups by 5-year age group.</p><p><b>RESULTS</b>SI reached peak values in 21-25 year group in men (range: 111.45 +/- 21.19) and in 16-20 year group in women (range: 101.26 +/- 17.51). Then the SI value began to decline with aging. The SI featured by a typical dual-peak curve in women and the decrease rate of SI was faster in women than in men over 61 years. Multivariate linear regression analysis showed significantly negative correlation between SI and age (P < 0.001), positive correlation between SI and body weight (P < 0.05 for men; P < 0.01 for women), and positive correlation between SI and height in women (P < 0.01).</p><p><b>CONCLUSION</b>SI correlates with age, height, and weight. The acquired SI value may provide a reference for the diagnosis of osteoporosis.</p>

Analysis of the levels of serum total calcium and inorganic phosphate of 2,342 children in Beijing / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the changes of serum total calcium (Ca) and inorganic phosphate (P) levels during children growth and related factors.</p><p><b>METHODS</b>Using a stratified-multi-steps-cluster sampling method, we selected 2,342 healthy children aged 10-18 years from urban and suburban areas of Beijing from September 2001 to December 2001 to test the levels of serum Ca and P. Their meal status was also surveyed to analyse the correlation of the leves of serum Ca and P with sex, age, height, weight, and diet on statistic basis.</p><p><b>RESULTS</b>The Ca levels of Beijing children were (2.39 +/- 0.12) mmol/L, which had a positive correlation with age, height, and weight (P < 0.01). The Ca levels of female children were somewhat higher than those of male [male, (2.38 +/- 0.12) mmol/L; female, (2.39 +/- 0.12) mmol/L; P < 0.05]. The Ca levels of urban children were significantly higher than those of suburban children [urban, (2.40 +/- 0.13) mmol/L; suburban, (2.37 +/- 0.10) mmol/L; P < 0.001]. The P levels of Beijing children were (1.39 +/- 0.18) mmol/L, which had a negative correlation with age, height, and weight (P < 0.01). The P levels of male children were significantly higher than those of female [male, (1.43 +/- 0.18) mmol/L; female, (1.36 +/- 0.17) mmol/L; P < 0.001]. The P levels of urban children were significant higher than those of suburban children [urban, (1.41 +/- 0.19) mmol/L; suburban, (1.38 +/- 0.16) mmol/L; P < 0.001]. The Ca levels of Beijing children had a negative correlation with P levels (r=-0.141, P < 0.01). [Ca] x [P] (mmol/L) of Beijing children were 3.32 +/- 0.44. The value of [Ca] x [P] reached peak by 3.45 +/- 0.46 when Beijing children were of 13-14 years old, and then the value declined with increasing age.</p><p><b>CONCLUSION</b>The levels of serum Ca and P correlates with sex, age, growth, and diet. The level of serum Ca goes up while P goes down during the children growth.</p>

Effect of AP-1 on expression of plasminogen activator inhibitor-1 in human vascular endothelial cells / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the effect of nuclear transcription factor AP-1 on tumor necrosis factor alpha (TNF-alpha) or minimal modified low density lipoprotein (mmLDL)-induced expression of plasminogen activator inhibitor-1 (PAI-1) in human vascular endothelial cells.</p><p><b>METHODS</b>Using gene recombination techniques, four luciferase reporter gene plasmids containing different length of human PAI-1 gene promoter were constructed. Through the transient transfection analysis, the roles of AP-1 element (from -823 bp to -553 bp) in PAI-1 promoter have been determined. In order to further verify the role of AP-1 element, the three site-directed mutants were recovered using PCR and sequencing assay.</p><p><b>RESULTS</b>The induction by TNF-alpha or mmLDL were decreased markedly when the three AP-1 elements in PAI-1 promoter had been mutated respectively.</p><p><b>CONCLUSIONS</b>These results indicate that the AP-1 element in PAI-1 promoter may have important role in PAI-1 gene transcriptions in endothelial cells induced by TNF-alpha or mmLDL.</p>

Effects of TNF-alpha or mmLDL on PAI-1 expression in human umbilical vein endothelial cells / 中国医学科学院学报

<p><b>OBJECTIVE</b>To demonstrate the changes of PAI-1 activity and mRNA expressions induced by tumor necrosis factor alpha (TNF-alpha) or minimally modified low-density lipoprotein (mmLDL) in human umbilical vein endothelial cells (HUVECs).</p><p><b>METHODS</b>The PAI-1 activity in HUVECs culture medium was measured by chromogenic assay. The PAI-1 mRNA expressions were determined by Northern blot. The mitogen-activated protein kinase-kinase (MAPKK) inhibitor and protein kinase C (PKC) inhibitor were used to intervene the inductions by TNF-alpha or mmLDL.</p><p><b>RESULTS</b>The PAI-1 activity and mRNA level were increased when HUVECs were exposed to TNF-alpha or mmLDL. The MAPKK inhibitor (PD98059, 60 mumol/L) could markedly inhibit PAI-1 activity and mRNA expression induced by TNF-alpha (100 U/ml) or mmLDL (50 micrograms/ml). But Staurosporine (10 nmol/L) and H7 (15 mumol/L), which were the PKC inhibitors, had no significant inhibition effect.</p><p><b>CONCLUSIONS</b>(1) TNF-alpha or mmLDL could induce PAI-1 activity and mRNA expression in HUVECs. (2) Increase of PAI-1 activity induced by TNF-alpha and mmLDL was related to its mRNA expression. (3) The MAPK pathway may play a role in PAI-1 expression induced by TNF-alpha or mmLDL.</p>