Objective:It has been proposed that blood pressure variability(BPV) is positively related to end-organ damage(EOD) in hypertension.The present work was designed to observe the effects of long-term treatment with nitrendipine and hydralazine on BPV and EOD in spontaneously hypertensive rats(SHR),to examine the hypothesis that lowering BPV with an antihypertensive drug is an important factor in organ protection.Design and methods:Drugs were mixed in rat chow.After 4 months of drug administration,blood pressure was recorded continuously in conscious freely moving rats for 24 h.The heart,kidneys,and brain were then isolated and examined.Results:It was found that nitrendipine significantly decreased blood pressure and BPV,and significantly decreased EOD score in SHR.Hydralazine decreased blood pressure,but did not lower BPV.No effect on EOD was found in hydralazine-treated rats.In control rat(n=38),EOD score was weakly related to systolic blood pressure(r=0.331,P<0.05) and closely related to long-term systolic BPV(r=0.551,P<0.01).In nitrendipine-treated rats,EOD score was closely related to long-term systolic BPV(r=0.602,P<0.01),but not to blood pressure level(r=0.174,P>0.05).Conclusion:BPV plays an important role in the organ-protecting effects of nitrendipine.

Objective To investigate the systolic synchrony of the left ventricle in patients with left ventricular hypertrophy (LVH) or with heart failure but preserved ejection fraction (HF-PEF),and to evaluate the impact of systolic dyssynchrony on left ventricular function.Methods During June 2011 to May 2014,a total of 352 patients(160 males,192 females,average age:(67.6±7.8)years) with essential hypertension (EH) were enrolled in this retrospective study.Ultrasonic and G-MP1 were performed for assessment of left ventricular remodeling and systolic synchrony and the results were statistically analyzed by oneway analysis of variance and x2 test.Relationship between BNP and synchronic parameters as well as other clinical factors were analyzed by partial correlation analysis.Results The EH patients were divided into hypertension group (rt =182),LVH group (n =74) and HF-PEF group (n =96).In comparison to hypertension group,significant LVH developed in LVH and HF-PEF groups although the LVEF was still preserved.The LVMI of the 3 groups were (94.4±10.1),(121.1±9.8) and (123.2±10.9) g/m2,respectively(F=8.66,P＜0.05).The LVEF was (58.6±7.3)％,(60.8±10.4)％ and (55.1±4.6)％,respectively(F=2.89,P＞0.05).Diastolic dysfunction was identified in LVH and HF-PEF groups with significantly reduced E/A ratio (1.19±0.23,0.80±0.28,0.67±0.17;F=13.46,P＜0.05).Remarkable left ventricular systolic dyssynchrony with phase histogram bandwidth (PHB) of (88.4±8.6) ° and phase standard deviation (PSD) of (23.6±1.9)° and increased BNP of (228.4±69.7) ng/L were revealed in HF-PEF group.The BNP in HF-PEF group was significantly higher than that in LVH group((92.5±13.6) ng/L;q=8.63,P＜0.05).Positive correlation was found between BNP level and PHB,PSD,LVMI,respectively (r=0.277-0.331,all P＜0.05).Conclusion Left ventricular systolic dyssynchrony is concomitant with HF-PEF patients induced by EH,and this dyssynchrony might be one of the factors leading to diastolic dysfunction.

Ion trap performances are investigated based on digital ion trap technique with different collision gases at different pressures. Collision gases of helium (4 amu), nitrogen (28 amu) and argon (40 amu) with various pressures are adopted in ion excitation and dissociation stages to investigate the ion trap performances, including mass resolution, signal intensity, tandem mass spectrometric analysis ability and low-mass cut off (LMCO) effect. It is found that when heavy gas of argon is used, energy can be efficiently transferred and LMCO effect is decreased with higher ion capture and dissociation efficiencies but with low mass resolution. Higher mass resolution is realized with helium as collision gas. Furthermore, at the same gas pressure, heavy gas is beneficial to abundant fragment ions and structural information of precursor ion.

Objective:To explore the expressions of serum N-terminal osteocalcin (N-MID) and cytokeratin (CK) 5/6 in primary lung cancer patients with bone metastasis and their clinical significances.Methods:The clinical data of 96 patients with primary lung cancer admitted to Chengdu Second People's Hospital between February 2019 to February 2022 were retrospectively analyzed. All patients were divided into the bone metastasis group (38 cases) and the non-bone metastasis group (58 cases) according to whether bone metastasis occurred, and 45 healthy people who underwent physical examination during the same period were treated as the healthy control group. The expression levels of serum N-MID and CK5/6 in the bone metastasis group, the non-bone metastasis group and the healthy control group were compared. Logistic regression was used to analyze the factors affecting bone metastasis in patients with primary lung cancer; receiver operating characteristic (ROC) curve analysis was used to analyze the value of the expression levels of serum N-MID and CK5/6 in predicting bone metastasis in patients with primary lung cancer.Results:The composition ratio of patients with pathological stage Ⅲ-Ⅳ, serum bone-derived alkaline phosphatase and N-MID expression levels in the bone metastasis group were higher than those in the non-bone metastasis group (all P < 0.05). The expression level of serum N-MID in the bone metastasis group and non-bone metastasis group was higher than that in the healthy control group [(26.0±5.3) ng/ml, (15.3±3.1) ng/ml vs. (9.9±1.7) ng/ml, F = 224.27, P < 0.001], and there were statistically significant differences in the serum N-MID expression level of the pairwise comparison among the three groups (all P < 0.05). The expression level of serum CK5/6 in the bone metastasis group and the non-bone metastasis group was lower than that in the healthy control group [(3.6±0.7) ng/ml, (7.3±1.4) ng/ml vs. (10.6±2.4) ng/ml, F = 178.11, P < 0.001], and there were statistically significant differences in the serum CK5/6 expression level of the pairwise comparison among the three groups (all P < 0.05). Multivariate analysis showed that CK5/6, N-MID and bone-derived alkaline phosphatase were independent affecting factors for bone metastasis in patients with primary lung cancer ( OR = 4.088, 3.615, 2.892, all P < 0.05). ROC curve analysis showed that the optimal cut-off values of serum N-MID and CK5/6 expression levels for predicting bone metastasis in patients with primary lung cancer were 18.59 ng/ml and 4.71 ng/ml; the corresponding the area under the curve (AUC) was 0.881 and 0.862, respectively; and the specificity and AUC of the combination of serum N-MID and CK5/6 in predicting the bone metastasis in patients with primary lung cancer was 98.28% and 0.937 (95% CI 0.869-0.977), respectively; the AUC predicted by the combination of both was higher than that by serum N-MID or CK5/6 single (all P < 0.001). Conclusions:The expression levels of serum N-MID and CK5/6 in primary lung cancer patients with bone metastasis are abnormally changed. Clinical detection of serum N-MID and CK5/6 expression levels may be used as sensitive indicators for predicting the bone metastasis in patients with primary lung cancer.