[Association of fibroblast growth factor 23 with age-related cardiac diastolic function subclinical state in a healthy Chinese population].

Objective: To determine the association of serum fibroblast growth factor-23 concentrations with age-related cardiac diastolic function subclinical state and whether this association differs by sex. Methods: Seven hundred sixteen healthy subjects (aged 35-89 years, 68.4% female) were selected from National Basic Research Program of China (973 Program-China Medical University subsection) between January 2014 and February 2015 and assigned into 4 groups according to sex and age:< 60 years old male and female group, ≥ 60 years old male and female group. Blood biochemical indicators and general clinical data of the subjects were measured. The glomerular filtration rate (eGFR) were estimated using the Modified Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI-ASIA) equation. The fibroblast factor 23 (FGF-23), C-reactive protein (CRP) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). Cardiac structure and function parameters including left atrial diameter (LAD), inter-ventricular septum thickness (IVST), left ventricle posterior wall thickness (LVPWT), left ventricle mass index (LVMI),left atrial mass index (LAVI) and the ratio of peak velocity of early filling to the septal early peak diastolic mitral annulus velocity(E/e') were measured by echocardiography. Association between serum FGF-23 and aging-related diastolic function subclinical status was analyzed by binary Logistic regression analysis. Results: (1) Serum log-transformed FGF-23 levels were significantly higher in males than in females [(2.0±0.3) ng/L vs (1.9±0.4) ng/L, P<0.05]. (2) Cardiac diastolic function gradually decreased with age, and age related cardiac diastolic function decline of female was significantly higher than males[E/e':<60 years old male group (7.6±2.6), ≥ 60 years old male group (8.6±2.7), P<0.01;<60 years old female group (8.3±2.3), ≥ 60 years old female group (9.5±3.1), P<0.01; LAVI:<60 years old female group (14±5) ml/m(2), ≥ 60 years old female group (16±5) ml/m(2), P<0.01]. (3) Serum FGF-23 was significantly positively correlated with age (r=0.089, P<0.05) and LAVI (r=0.084, P<0.05) in total study population while with E/e' (r=0.149, P<0.05) only in males. There was no significant correlation between serum FGF-23 and cardiac diastolic function parameters in females. (4) Binary Logistic regression analysis showed that median and high FGF-23 were independently associated with age-related cardiac diastolic function decline (OR=2.831, 95% CI: 1.144-7.009, P=0.024; OR=2.548, 95% CI: 1.053-6.163, P=0.038) in males. Conclusions: Serum FGF-23 concentrations are associated with age-related cardiac diastolic function subclinical state in a healthy Chinese population. High levels of FGF-23 are independently associated with age-related cardiac diastolic function decline in males.

Peripheral Blood Leukocyte Telomere Length Is Associated with Age but Not Renal Function: A Cross-Sectional Follow-Up Study.

OBJECTIVES: We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese. METHODS: The telomere restriction fragment (TRF) length of leukocytes in the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed. RESULTS: Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function. CONCLUSION: The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.

Leptin and leptin receptor gene polymorphisms are correlated with production performance in the Arctic fox.

The polymerase chain reaction-single-strand conformation polymorphism technique was employed to measure mononucleotide diversity in the coding region of the leptin and leptin receptor genes in the Arctic fox. The relationships between specific genetic mutations and reproductive performance in Arctic foxes were determined to im-prove breeding strategies. We found that a leptin gene polymorphism was significantly associated with body weight (P < 0.01), abdominal circumference (P < 0.01), and fur length (P < 0.01). Furthermore, a polymorphism in the leptin receptor gene was associated with carcass weight and guard hair length (P < 0.01). Leptin and leptin receptor gene combinatorial genotypes were significantly associated with abdominal circumference, fur length (P < 0.01), and body weight (P < 0.05). The leptin gene is thus a key gene affecting body weight, abdominal circumference, and fur length in Arctic foxes, whereas variations in the leptin receptor mainly affect carcass weight and guard hair. The marker loci identified in this study can be used to assist in the selection of Arctic foxes for breeding to raise the production performance of this species.

Association of Klotho and interleukin 6 gene polymorphisms with aging in Han Chinese population.

Certain gene polymorphisms are associated with human aging. This study investigated polymorphisms of a metabolism-related gene, Klotho, and an inflammatory gene, IL6, for association with the aging process in a healthy Han Chinese population. A total of 482 healthy subjects were recruited and divided into aging and young groups according to chronological age and biological age. Snapshots were used to detect a Klotho gene tag SNP (rs571118) and the F-SNPs rs9536314 (F352V) and rs9527025 (C370S), and an interleukin 6 (IL-6) gene tag SNP (rs1524107) and the F-SNPs rs1800795 (-174G/C) and rs1800796 (-572G/C). Klotho F352V and IL-6-174G/C was G homozygous, C370S was T homozygous while IL-6-572G/C MAF less than 5%. There was a statistically significant difference in the Klotho rs571118 SNP between chronological age groups, but not biological age groups. However, other SNPs, including IL-6 gene SNPs, didn't correlate with age in the Han Chinese population. Human aging is a complex process that includes chronological and biological aging. Our current data showed that Klotho gene rs571118 SNP was associated with chronological aging, but not biological aging, in a Han Chinese population. Further study will investigate genetic build up for the difference between chronological and biological aging.

Construction of an integral formula of biological age for a healthy Chinese population using principle component analysis.

BACKGROUND: Whereas chronological age (CA) cannot distinguish functional differences among individuals of the same age, the biological age (BA) may be used to reflect the functional state of the body. The purpose of this study was to construct an integral formula of the BA, by using principle component analysis (PCA). METHODS: The vital organ function of 505 healthy individuals of Han origin (age 35-91 years) was examined. A total of 114 indicators of cardiovascular, pulmonary, and brain functions, and clinical, inflammatory, genetic, psychological, and life habit factors were assessed as candidate indicators of aging. Candidate indicators were submitted with CA to correlation and redundancy analyses. The PCA method was used to build an integral formula of the BA for the population. RESULTS: Seven biomarkers were selected in accordance with a certain load standard. These biomarkers included the trail making test (TMT), pulse pressure (PP), mitral valve annulus ventricular septum of the peak velocity of early filling (MVES), minimum carotid artery intimal-medial thickness (IMTmin), maximum internal diameter of the carotid artery (Dmax), maximal midexpiratory flow rate 75/25 (MMEF75/25), and Cystatin C (CysC). The formula for the BA was: BA = 0.0685 (TMT) + 0.267 (PP) - 1.375 (MVES) + 22.443 (IMTmin) + 2.962 (Dmax) - 2.332 (MMEF75/25) + 16.104 (CysC) + 0.137 (CA) + 0.492. CONCLUSION: Several genetic and lifestyle indicators were considered as candidate markers of aging. However, ultimately, only markers reflecting the function of the vital organs were included in the BA formula. This study represents a useful attempt to employ multiple indicators to build a comprehensive BA evaluation formula of aging populations.

Genetic diversity of the Arctic fox using SRAP markers.

Sequence-related amplified polymorphism (SRAP) is a recently developed molecular marker technique that is stable, simple, reliable, and achieves moderate to high numbers of codominant markers. This study is the first to apply SRAP markers in a mammal, namely the Arctic fox. In order to investigate the genetic diversity of the Arctic fox and to provide a reference for use of its germplasm, we analyzed 7 populations of Arctic fox by SRAP. The genetic similarity coefficient, genetic distance, proportion of polymorphic loci, total genetic diversity (Ht), genetic diversity within populations (Hs), and genetic differentiation (Gst) were calculated using the Popgene software package. The results indicated abundant genetic diversity among the different populations of Arctic fox studied in China. The genetic similarity coefficient ranged from 0.1694 to 0.0417, genetic distance ranged from 0.8442 to 0.9592, and the proportion of polymorphic loci was smallest in the TS group. Genetic diversity ranged from 0.2535 to 0.3791, Ht was 0.3770, Hs was 0.3158, Gst was 0.1624, and gene flow (Nm) was estimated at 2.5790. Thus, a high level of genetic diversity and many genetic relationships were found in the populations of Arctic fox evaluated in this study.

Magnetic properties of (Fe50Co50)(1-x)-Gdx thin films with diluted Gd doping.

(Fe50Co50)(1-x)-Gdx thin films (30 nm) with x<15% deposited on silicon substrates by magnetron sputtering were investigated by X-ray diffraction, vibrating sample magnetometer, and ferromagnetic resonance. Theoretical fittings of the angular dependent ferromagnetic resonance field of the FeCoGd films have been performed using the Landau-Lifshitz equation It is found that the ferromagnetic resonance experimental data is well fitted by the theory and various magnetic properties have been extracted in accordance. The saturation magnetization decreases from 22750 Oe at x = 0% to 14079 Oe at x = 14% in the FeCo-Gd film, and the perpendicular magnetic anisotropy has changed from an easy film plane to an easy film normal geometry. The gyromagnetic ratio, as well as the Landé g factor, are found increased also with increasing Gd content, i.e. from g = 2.08 at x = 0% to g = 2.29 at x = 14%. An enhancement of the L-S coupling in the presence of a low Gd content has been concluded based on an observable increase from 0.011 at x = 12% up to 0.015 at x = 14% in the Gilbert damping.

Fluoroscopically guided nose tube drainage of mediastinal abscesses in post-operative gastro-oesophageal anastomotic leakage.

OBJECTIVE: The aim of this study was to retrospectively evaluate the technical success rates and clinical effectiveness of fluoroscopically guided nose tube drainage of mediastinal abscesses and a nasojejunum feeding tube in post-operative gastro-oesophageal anastomotic leakage (GEAL). METHODS: From January 2006 to June 2011, 18 cases of post-operative GEAL with mediastinal abscesses after oesophagectomy with intrathoracic oesophagogastric anastomotic procedures for oesophageal and cardiac carcinoma were treated by insertion of a nose drainage tube and nasojejunum feeding tube under fluoroscopic guidance. We evaluated the feasibility of two-tube insertion to facilitate leakage site closure and complete resolution of the abscess, and the patients' nutritional benefit was also evaluated by checking the serum albumin level between pre- and post-enteral feeding via the feeding tube. RESULTS: The two tubes were placed successfully under fluoroscopic guidance in 18 patients (100%). The procedure time for two-tube insertion ranged from 20 to 40 min (mean 30 min). 17 patients (94%) achieved leakage site closure after two-tube insertion and had a good tolerance of two tubes in the nasal cavity. The serum albumin level was significant, increased from pre-enteral feeding (2.49 ± 0.42 g dl(-1)) to the post-enteral feeding (3.58 ± 0.47 g dl(-1)) via the feeding tube (p<0.001). The duration of follow-up ranged from 1 to 49 months (mean 19 months). CONCLUSION: The insertion of nose tube drainage and a nasojejunum feeding tube under fluoroscopic guidance is safe, and it provides effective relief from mediastinal abscesses in GEAL after oesophagectomy. Moreover, our findings indicate that two-tube insertion may be used as a selective procedure to treat mediastinal abscesses in post-operative GEAL. Advances in knowledge Directive drainage of mediastinal abscesses in post-operative GEAL may be an effective treatment.

Rotation of the pinning direction in the exchange bias training effect in polycrystalline NiFe/FeMn bilayers.

For polycrystalline NiFe/FeMn bilayers, we have observed and quantified the rotation of the pinning direction in the exchange bias training and recovery effects. During consecutive hysteresis loops, the rotation of the pinning direction strongly depends on the magnetization reversal mechanism of the ferromagnet layer. The interfacial uncompensated magnetic moment of antiferromagnetic grains may be irreversibly switched and rotated when the magnetization reversal process of the ferromagnet layer is accompanied by domain wall motion and domain rotation, respectively.

Susceptibility to active decompensated cirrhosis is associated with polymorphisms of intercellular adhesion molecule-1 (ICAM-1) in chronic HBV carriers.

Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the pathogenesis of viral hepatitis B. Several inflammatory diseases are associated with distinct polymorphisms of the ICAM-1 gene. The aims of this study were to analyse the association of ICAM-1 polymorphisms G241R and K469E with susceptibility to active decompensated cirrhosis in chronic hepatitis B virus (HBV) carriers. The polymorphisms at codons G241R and K469E of ICAM-1 were analysed by sequence-specific primer polymerase chain reaction (PCR-SSP) in 572 unrelated chronic HBV carriers and 157 unrelated healthy HBV non-infected blood donors. There were significantly increased frequencies of R at codon 241 and E at codon 469 in patients with active decompensated cirrhosis (38.3% and 58.3%), compared with patients with chronic hepatitis B (CHB; 21.9% and 46.5%) and chronic asymptomatic HBV carriers (AsC; 12.6% and 40.3%). The frequencies of R241-E469 haplotype and genotypes carrying at least one R241-E469 haplotype were significantly higher in patients with active decompensated cirrhosis than those in patients with CHB (38.3% and 63.3%vs 21.9% and 36.7%), and significantly higher in patients with CHB than those in AsC (21.9% and 36.7%vs 12.6% and 23.3%). The ICAM-1 polymorphisms at codons G241R and E469K were associated with the disease susceptibility, and susceptibility to active decompensated cirrhosis is significantly increased in chronic HBV carriers carrying at least one R241-E469 haplotype.

Coronary perfusion related changes in myocardial contractile force and systolic ventricular stiffness.

OBJECTIVE: The mechanism by which changes in coronary perfusion alter myocardial oxygen consumption (MVO2; Gregg phenomenon) is controversial. This study examined the effect of coronary perfusion on myocardial contractile force and systolic ventricular stiffness in the intact, ejecting heart. METHODS: During selective perfusion of the left anterior descending coronary artery, coronary blood flow was changed with or without concurrent changes in coronary perfusion pressure in 19 alpha chloralose anaesthetised dogs. Regional myocardial segment length (end diastolic length; end systolic length) and developed force were measured with piezoelectric crystals and with a miniature force transducer, respectively. MVO2 was calculated from coronary flow and arteriovenous O2 difference. The slope of the force-length curve during ejection period (delta F/delta SL) was used as an index of systolic myocardial stiffness. RESULTS: When coronary perfusion pressure was varied from 60 to 180 mm Hg (protocol 1, n = 11), maximum developed force (Fmax), delta F/delta SL, and MVO2 increased with perfusion pressure while end diastolic length, segmental shortening, and other haemodynamic variables stayed constant. When coronary blood flow was increased at constant perfusion pressure by infusion of either a low dose or a high dose adenosine (protocol 2, n = 8), Fmax, delta F/delta SL, and MVO2 increased while end diastolic length, segmental shortening, and other haemodynamic variables stayed constant. MVO2 and delta F/delta SL increased more steeply with flow in protocol 1. CONCLUSIONS: (1) Increased coronary blood flow enhances myocardial contractile force, systolic ventricular stiffness, and MVO2 in the intact, ejecting heart. (2) Coronary blood flow induced changes in myocardial contractile force and systolic ventricular stiffness, but not end diastolic length, are probably responsible for coronary blood flow related changes in MVO2.

Coronary pressure-flow autoregulation protects myocardium from pressure-induced changes in oxygen consumption.

Pressure-flow autoregulation minimizes changes in coronary blood flow (CBF) when coronary perfusion pressure (CPP) is altered. This investigation determined if autoregulation also minimizes CPP-induced changes in coronary vascular volume (CVV) and CVV-dependent changes in myocardial oxygen consumption (MVO2). In 11 anesthetized dogs, the left anterior descending coronary artery was cannulated, and responses to 20-mmHg changes in CPP were examined over a range of CPP from 60 to 180 mmHg. Changes in CPP had no significant effect on systemic hemodynamics or on left ventricular end-diastolic segment length, end-systolic segment length, or percent segment shortening. In hearts with effective pressure-flow autoregulation [closed-loop gain (GC) > 0.4], CVV increased 0.06%/mmHg change in CPP. For the same hearts, MVO2 increased 0.04%/mmHg change in CPP. In hearts with ineffective autoregulation (GC < 0.4), CVV increased 0.97%/mmHg (P < 0.001 vs. autoregulating hearts), and MVO2 increased 0.41%/mmHg (P < 0.001 vs. autoregulating hearts). MVO2 and CVV were correlated (r = 0.69, P < 0.0001) independently of autoregulatory capability, but only when autoregulation was poor and capacitance was elevated did CPP significantly affect MVO2. We conclude that pressure-flow autoregulation protects myocardium from CPP-induced changes in CVV, which in turn produces changes in oxygen consumption.

Preconditioning with supply-demand imbalance limits infarct size in dog heart.

OBJECTIVE: The aim was to examine whether an absolute reduction in energy supply is required for preconditioning against myocardial infarction, and whether an episode of increased adrenergic activity with or without supply-demand imbalance is capable of triggering cardioprotection. METHODS: 41 anaesthetised dogs were subjected to 60 min left circumflex artery occlusion followed by 5 h reperfusion (control group, n = 8). The left stellate cardiac nerve was stimulated for 5 min starting 10 min before coronary occlusion in the stimulation group (STIM group, n = 8). The left circumflex artery flow increase that normally accompanies adrenergic stimulation was prevented by a pneumatic occluder in another group (STIM-R group, n = 8). Infarct size and area at risk were determined by triphenyl tetrazolium chloride staining and Evans blue dye, respectively. Regional myocardial blood flow during ischaemia and during stimulation (STIM-R group) was measured with radioactive microspheres. RESULTS: In the STIM group, adrenergic stimulation increased the coronary blood flow by approximately twofold from baseline. In the STIM-R group, transmural myocardial blood flow in the flow restricted left circumflex artery region was 64% of the flow to the non-flow-restricted left anterior descending coronary artery region. Haemodynamic variables were not different among the experimental groups except during adrenergic stimulation. Collateral blood flow and area at risk were comparable among the three groups. Infarct size as a percentage of area at risk (%IS/AAR) was significantly smaller in the STIM-R group [7.6(3.2)%] than in the control group [27.9(7.3)%], whereas %IS/AAR in the STIM group [21.7(4.1)%] was not. Furthermore, the regression line between collateral blood flow and %IS/AAR was significantly shifted downward in the STIM-R group, but not in the STIM group. CONCLUSIONS: (1) Transient energy supply-demand imbalance triggers infarct size limitation; an absolute reduction in energy supply is not required for preconditioning. (2) Increased adrenergic activity without supply-demand imbalance seems unable to trigger appreciable cardioprotection.

Effect of acute trauma on the levels of intracellular cAMP, cGMP and DNA: studies on endocrinology and metabolism.

In this experiment, we used morgrel dogs to study the effect of trauma on the neuro-endocrine and metabolic organs and the effects of hormones on metabolism by determining the levels of intracellular cAMP, cGMP and DNA. From the changes in intracellular nucleotides, we learned that many neuro-endocrine organs and the main metabolic organs are characteristic of predominance in alpha-adrenoreceptor after trauma, thereby leading to high blood sugar.

[The kinetics of plasma coagulation fibrinolysis levels in acute myocardial infarction before and after treatment with intravenous urokinase].

The levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor (PAI) and other substances of coagulation-fibrinolysis, such as fibronectin (Fn) and von willebrand factor (vWF) as well as the activity content of antithrombin-III(AT-III) in plasma were determined in 20 patients with acute myocardial infarction (AMI). In 11 of them these measurements were carried out before and after the treatment with urokinase (UK1000 000 IU). The results suggested that the function of coagulation-fibrinolytic system was disturbed in AMI. Thrombolytic treatment with UK could interfere and improve the stabilization of fibrinolytic activity in the body, but these actions last only short time. Some substances of coagulation showed change with UK treatment.