Independent and combined associations of upper and lower limb strength with all-cause mortality in community-based older adults: findings from the Chinese Longitudinal Healthy Longevity Survey

OBJECTIVE

With the acceleration of aging progress, China is projected to have the largest older population globally. This study aimed to examine the association of upper limb strength (ULS) and lower limb strength (LLS) with all-cause mortality based on the Chinese Longitudinal Healthy Longevity Survey (2012-2018).

STUDY DESIGN

This is a prospective cohort study.

METHODS

Participants were 2442 older adults (aged 84.98 ± 11.94 years) recruited from eight longevity areas in China. Limb muscle strength was evaluated using handgrip strength and objective physical examinations. Cox proportional hazards regression was used to analyze the association of limb muscle strength with all-cause mortality. Demographic characteristics, health status, and biological markers were included as confounders.

RESULTS

Over a median follow-up period of 42.2 months, 993 older people died. After adjusting for all covariates, low ULS was associated with higher mortality risk (hazard ratio [HR] = 1.51, 95% confidence interval [CI] = 1.25-1.84), and the association of low LLS with all-cause mortality was only significant in women (HR = 1.36, 95% CI = 1.04-1.79). Participants with combined low ULS and low LLS had the highest risk of mortality than those with normal limb muscle strength (hazard ratio = 2.06, 95% confidence interval = 1.61-2.63). The combined association of ULS and LLS with mortality was robust in subgroup and sensitivity analyses.

CONCLUSION

Low ULS and low LLS were independently and synergistically associated with higher all-cause mortality risk. Considering the high prevalence of limb muscle weakness among Chinese older adults, especially the oldest-old, limb strength could be considered as a potential doable mortality predictor for community health care.

Combination of Intracardiac Echocardiography and Contact Force Sensing for Left Ventricular Papillary Muscle Arrhythmias

OBJECTIVES

The catheter ablation of ventricular arrhythmias (VAs) arising from the left ventricular (LV) papillary muscles (PMs) is challenging. This study sought to address whether the combination of intracardiac echocardiography (ICE) and contact force sensing (CFS) can improve the acute and long-term ablation outcomes of left ventricular papillary muscle arrhythmias.

METHODS AND RESULTS

From May 2015 to August 2022, a total of thirty-three patients underwent catheter ablation for LV PM arrhythmias: VAs were located in anterolateral PMs in 11 and posteromedial PMs in 22. A combination of intracardiac echocardiography (ICE) and contact force sensing (CFS) was used in 21 of the 33 procedures. A mean of 6.93 ± 4.91 for lesions was used per patient, comparable between the CFS/ICE and no ICE/CFS (4.90 ± 2.23 vs. 10.17 ± 5.89; p = 0.011). The mean CF achieved in the ICE/CFS group was 7.52 ± 3.31 g. Less X-ray time was used in the combination group (CFS/ICE: 165.67 ± 47.80 S vs. no ICE/CFS: 365.00 ± 183.73 S; p < 0.001). An acute success rate of 100% was achieved for the ICE/CFS group (n = 22) and 66.67% for the no ICE/CFS group (n = 8). VA recurrence at the 11.21 ± 7.21-month follow-up was 14.2% for the ICE/CFS group and 50% for the no ICE/CFS group (p = 0.04). No severe complications occurred in all patients.

CONCLUSIONS

The combination of intracardiac echocardiography (ICE) and contact force sensing (CFS) could provide precise geometries of cardiac endocavitary structures and accurate contact information for the catheter during ablation, which improved acute and long-term ablation outcomes. The routine adoption of this strategy should be considered to improve the outcomes of LV PM VA ablation.

Case report: Double-chambered right ventricle diagnosed in a middle-aged female with hypertrophic cardiomyopathy and atrial flutter: A rare case

Double-chambered right ventricle (DCRV) is a rare congenital heart defect in adults, manifesting with progressive right ventricular outflow tract obstruction. We describe the first case of DCRV coexisting with hypertrophic cardiomyopathy, which is complicated by atrial flutter. A middle-aged woman with recurrent symptomatic atrial flutter who had previously been diagnosed with biventricular hypertrophic cardiomyopathy was admitted to our department. Echocardiography and cardiac magnetic resonance revealed asymmetrical interventricular septal hypertrophy, and abnormal muscle bundles within the right ventricle, generating an obstructive gradient. Genetic testing detected a hypertrophic cardiomyopathy-associated mutation: MYH7, c.4135G &gt; A, p. Ala1379Thr. A diagnosis of DCRV complicated by hypertrophic cardiomyopathy and atrial flutter was made. Surgical intervention was performed, which included radiofrequency ablation, removal of abnormal muscle bundles, and ventricular septal defect repair. Intraoperative transesophageal echocardiography demonstrated the well-corrected right ventricular outflow tract. Free of early postoperative complications, the patient was discharged in sinus rhythm on the 11th day after the surgery. Unfortunately, the patient died from a sudden death 38 days following the surgery. In conclusion, the coexistence of DCRV with hypertrophic cardiomyopathy in patients is an uncommon condition. The present case highlights the importance of diagnostic imaging in the management of this disorder.

SIRT3 protects endothelial cells from high glucose-induced senescence and dysfunction via the p53 pathway

Hyperglycemia induces endothelial cells (ECs) dysfunction and vascular complications by accelerating ECs senescence. It also induces downregulation of sirtuins (SIRTs). However, the molecular mechanism involved in the regulation of ECs senescence by SIRT3 remains unclear. Here, we showed that high glucose (HG) decreased the expression level of SIRT3 in human umbilical vein endothelial cells (HUVECs), increased the proportion of cells expressing senescence-associated galactosidase (SA-gal), and HG damaged the cell's ability to form tubule networks on Matrigel. However, transfection with adenoviral construct including SIRT3 significantly inhibited HG-induced SA-gal activity, decreased p53 acetylation level at the site Lys 320 (k320), and overexpression of SIRT3 antagonized high glucose-induced angiogenic dysfunction. Our results suggested a possible molecular mechanism involving HG-SIRT3-p53 in ECs senescence.

[Cellular damage of low-dose combined exposure to mercury, lead and cadmium on hippocampal neurons in rats]

Objective: To observe the cellular damage of low-dose combined exposure to Hg, Pb and Cd on hippocampal neurons in rat. Methods: SH-SY5Y cells were randomly divided into 8 groups by 2×2×2 factorial design: control group, Pb exposure group, Hg exposure group, Pb+Hg exposure group, Pb+Cd exposure group, Hg+Cd exposure group and Pb+Cd+Hg exposure group. And the cell viabilities were measured. On this basis, an animal model was established. Twenty eight-week-old SD pregnant rats were randomly divided into four groups by random number table, and five in each group: the control group(distilled water), 1-fold metal mixture exposure group (1×MM, poisoning solution containing mercury chloride 0.15 mg/L, lead acetate trihydrate 25 mg/L, cadmium chloride 7.5 mg/L), 5-fold metal mixture exposure group (5×MM, poisoning solution containing mercury chloride 0.75 mg/L, lead acetate trihydrate 125.00 mg/L, cadmium chloride 37.50 mg/L), 10-fold metal mixture exposure group (10×MM, poisoning solution containing mercury chloride 1.50 mg/L, lead acetate trihydrate 250.00 mg/L, cadmium chloride 75.00 mg/L). Pregnant rats drank water until delivery. Twenty male pups were selected and exposed to these metals through breast milk until weaned. The heavy metals dose of poisoning water was adjusted, and then the weaned rats were exposed to heavy metals via drinking poisoning water until adulthood (postnatal day 83). The blood samples and brain hippocampus samples were collected to observe the ultrastructural changes of hippocampus, and to determine the levels of Hg, Pb and Cd in blood. In addition, apoptosis rate and fluorescence intensity of reactive oxygen species and intracellular free calcium concentration ([Ca(2+)](i)) in hippocampal neurons were measured. Results: Cellular factorial design analysis showed that Hg+Pb+Cd (at no observed adverse effect level, 1.0, 0.5 and 0.1 μmol/L, respectively)had a interaction on cell viability after 48 or 72 hours of combined exposure (P<0.05). The results of ultrastructure showed that mitochondria decreased, ridges and matrixes gradually dissolved in rat hippocampal neurons of 5×MM group; nuclear chromatin aggregated, more ridges and matrixes dissolved and the mitochondria also decreased in rat hippocampal neurons of 10×MM group. The concentration of Hg, Pb and Cd in the blood of 1×MM group, 5×MM group and 10×MM group were higher than those in the control group, and the differences were statistically significant (P<0.001). There was no significant difference in apoptosis rate between the 1×MM group and the control group. The apoptosis rate of 5×MM group and 10×MM group was higher than that in the control group, and the differences were statistically significant (P<0.001). There was no statistically significant difference in the fluorescence intensity of reactive oxygen species in hippocampal neurons of the 1×MM group and the control group. The fluorescence intensity of reactive oxygen species in the 5×MM group and the 10×MM group was higher than that in the control group, the difference was statistically significant (P<0.05). There was no significant difference in the fluorescence intensity of [Ca(2+)](i) between the 1×MM group and the control group. The fluorescence intensity values of [Ca(2+)](i) in the 5×MM group and the 10×MM group were higher than the control group, the differences were statistically significant (P<0.001). Conclusion: Low-level combined exposure to Hg, Pb, and Cd caused synergistic neurotoxic damage, and the process may be related to the changes of neuronal apoptosis, reactive oxide species, and [Ca(2+)](i) levels.

[Research on potential interaction between mitochondrial DNA copy number and related factors on risk of hypertension in coal miners]

Objective: To investigate the effects of mitochondrial DNA (mtDNA) copy number in peripheral blood and related factors on the risk of hypertension in coal miners. Methods: A case-control study was conducted in 378 coal miners with hypertension and 325 healthy coal miners recruited from Datong Coal Mine Group. A standard questionnaire was used to collect their general information, such as demographic characteristics, habits and occupational history. Fluorescence quantitative PCR was performed to detect the copy number of mtDNA. Logistic regression model was applied for identifying the related risk factors of hypertension and analyzing the interaction between mtDNA copy number and risk factors. Results: The prevalence of hypertension of high mtDNA copy number was lower than mtDNA copy numberin 0-5.67 group, but the difference was not statistically significant (P=0.414). Alcohol drinking (OR=1.80, 95% CI: 1.26-2.56), family history of hypertension (OR=1.74, 95% CI: 1.20- 2.50), work shifts (OR=0.69, 95% CI: 0.48-0.99), education level (P=0.012) and family monthly income level (P=0.001) were related to the prevalence of hypertension. There were potential interactions between mtDNA copy number and alcohol drinking, family monthly income level, family history of hypertension, respectively. Alcohol drinking was a risk factor for hypertension [1.77 (1.25-2.50)]. Potential interactions between mtDNA copy number and alcohol drinking reduced the risk of hypertension (OR=1.20, 95% CI: 1.07-1.35). Family history of hypertension was a risk factor for hypertension [1.81(1.26-2.59)]. Potential interactions between mtDNA copy number and family history of hypertension reduced the risk of hypertension (OR=1.24, 95%CI: 1.09-1.41). Family monthly income level was a protect factor for hypertension [0.55(0.46-0.66)]. Potential interactions between mtDNA copy number and family monthly income level increased the protection role of hypertension (OR=0.90, 95% CI: 0.86-0.94). Conclusion: mtDNA copy number variation was not significantly associated with the prevalence of hypertension in coal miners, but mtDNA copy number showed multiplication interaction on the prevalence of hypertension with alcohol drinking, family monthly income level as well as family history of hypertension and made their influences weaken.

Gas6 delays senescence in vascular smooth muscle cells through the PI3K/ Akt/FoxO signaling pathway

BACKGROUND/AIMS

Growth arrest-specific protein 6 (Gas6) is a cytokine that can be synthesized by a variety of cell types and secreted into the extracellular matrix. Previous studies have confirmed that Gas6 is involved in certain pathophysiological processes of the cardiovascular system through binding to its receptor, Axl. In the present study, we investigated the role of Gas6 in cellular senescence and explored the mechanisms underlying its activity.

METHODS

We used vascular smooth muscle cells (VSMCs) to create two cellular senescence models, one for replicative senescence (RS) and one for induced senescence (IS), to test the hypothesis that Gas6 delays senescence.

RESULTS

Gas6-treated cells appear relatively younger compared with non-Gas6-treated cells. In particular, Gas6-treated cells displayed decreased staining for SA-β-Gal, fewer G1 phase cells, and decreased levels of p16(INK4a) and p21(Cip1) expression; conversely, Gas6-treated cells displayed more S phase cells and significantly increased proliferation indexes. Furthermore, in both the IS and RS models with Gas6 treatment, the levels of PI3K, p-Akt, and p-FoxO3a decreased following Axl inhibition by R428; similarly, the levels of p-Akt and p-FoxO3a also decreased following PI3K inhibition by LY294002.

CONCLUSION

Gas6/Axl signaling is essential for delaying the cellular senescence process regulated by the PI3K/Akt/FoxO signaling pathway.

A medical costs study of older patients with acute myocardial infarction and metabolic syndrome in hospital

Background

Older patients with acute myocardial infarction (AMI) usually have a poor prognosis, but whether this poor prognosis leads to high hospital costs remains unclear. This study investigated the clinical outcomes of and costs incurred by older patients with AMI and metabolic syndrome (MS) in hospital.

Methods and results

Patients with AMI seen at Qilu Hospital of Shandong University between January 2011 and May 2013 were separated into four groups: young non-MS patients (n=282), older non-MS patients (n=324), young MS patients (n=217), and older MS patients (n=174). We found that advanced age was significantly associated with worse clinical outcomes, and that the clinical outcomes in patients with AMI and MS are also worsened. At the same cost (RMB¥10,000), older patients with and without MS had a markedly increased number of cardiovascular incidences compared with younger patients without MS. In a comparison of the incremental cost-effectiveness ratio (ICER) of percutaneous coronary intervention, older patients without MS had a lower ICER for cardiovascular incidences and a higher ICER for cardiac event-free survival rate when compared with young patients without MS, but a lower ICER for cardiovascular incidences and a higher ICER for cardiac event-free survival rate when compared with older MS patients.

Conclusion

Older AMI patients have poor clinical outcomes and their treatment is not cost-effective; however, the results are worse in patients with AMI and MS. Percutaneous coronary intervention is a cost-effective therapy in older patients with AMI, but its cost-effectiveness decreases in patients with AMI and MS.

Impact of type 2 diabetes mellitus on hospitalization costs in older patients with acute myocardial infarction

Background

The purpose of this study was to evaluate the impact of type 2 diabetes mellitus on hospitalization costs in older patients with acute myocardial infarction (MI).

Methods

Retrospective analysis of data from the case retrieval system of Qilu Hospital of Shandong University located in Jinan city of Shandong Province was done for patients with acute MI from January 1, 2011 to December 31, 2012.

Results

Stenting was an important factor affecting older patients’ total hospitalization costs (β=0.685, P=0.000) and treatment costs during the follow-up period (duration of hospital stay only, β=0.508, P=0.000). Stenting was also a protective factor in the prevention of acute heart failure (HF) in older patients with acute MI during the follow-up period (odds ratio 0.189, 95% confidence interval 0.059–0.602, P=0.005). Implementation of percutaneous coronary intervention reduced the incidence of acute HF in older inpatients with acute MI (27.8% versus 4.3%, P=0.001) and without diabetes (18.2% versus 3.8%, P=0.001). Moreover, among the elderly, the incremental cost-effectiveness ratio estimate for implementing percutaneous coronary intervention in diabetic patients was higher than in nondiabetic patients.

Conclusion

Stenting was a protective factor for preventing acute HF in the elderly during the follow-up period. From the perspective of reducing the incidence of acute HF in inpatients, implementation of percutaneous coronary intervention after an acute MI is more cost-effective in older patients with diabetes mellitus than in those without it.

[Non-anthraquinone constituents from Rheum sublanceolatum C. Y. Cheng et Kao]

OBJECTIVE

Study on the non-anthraquinone constituents from rhizoma and radix of Rheum sublanceolatum.

METHOD

The constituents were isolated through column chromatography and identified on the basis of their physiochemical and spectral data.

RESULT

Six non-anthraquinone constituents were isolated and identified as n-octacosanic acid, sitosterol, daucosterol, 2-methyl-5-carboxymethyl-7-hydroxychromone, piceatannol and 6-hydroxymusizin-8-O-beta-D-glucopyranoside.

CONCLUSION

All these compounds were firstly isolated from R. sublanceolatum.