Effect of strontium ranelate on rabbits with steroid-induced osteonecrosis of femoral head through TGF-β1/BMP2 pathway

OBJECTIVE

To study the effect of strontium ranelate (SR) on steroid-induced osteonecrosis of the femoral head (SIONFH) in rabbits and its regulatory mechanism.

MATERIALS AND METHODS

The ONFH model was established in 30 rabbits using steroid and they were randomly divided into Control group, Model group, and SR group. After SR intervention, the rabbits were sacrificed and sampled. The pathological injury of the femoral head in each group was detected via hematoxylin-eosin (HE) staining, the level of vascular endothelial growth factor (VEGF) in the femoral head in each group was detected via enzyme-linked immunosorbent assay (ELISA). The messenger ribonucleic acid (mRNA) and protein expression levels of transforming growth factor-β1 (TGF-β1), as well as the bone morphogenetic protein 2 (BMP2) in the femoral head in each group, were determined using Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting.

RESULTS

The rabbit model of SIONFH was successfully established. Compared with Control group, the Model group had a severer pathological injury of the femoral head, a lower level of VEGF in the femoral head, significantly decreased mRNA and protein levels of TGF-β1 and BMP2. Compared with Model group, the SR group had markedly improved pathological injury of the femoral head, a higher level of VEGF in the femoral head, significantly increased mRNA and protein levels of TGF-β1, as well as BMP2.

CONCLUSIONS

SR can remarkably improve the pathological injury of the femoral head and increase the expression of VEGF in SIONFH rabbits, whose potential mechanism may be related to the activation of the TGF-β1/BMP2 signaling pathway.

MiR-19a suppress apoptosis of myocardial cells in rats with myocardial ischemia/reperfusion through PTEN/Akt/P-Akt signaling pathway

OBJECTIVE

To detect differentially expressed micro ribonucleic acids (miRNAs) in rats with myocardial ischemia/reperfusion (MIR), and to explore the influence of miR-19a on MIR rats and its mechanism.

MATERIALS AND METHODS

Firstly, the Sprague-Dawley (SD) rats were used to prepare MIR models, RNAs were extracted, and miRNA sequencing analysis was carried out to determine differentially expressed miRNAs related to MIR. Secondly, the predicted target genes of miR-19a were collected, and WebGestalt was applied to analyze gene ontology (GO) and pathway enrichment. Thirdly, the expression of the related proteins and the apoptosis of myocardial cells in MIR rats were detected via Western blotting. Fourthly, the interaction between miR-19a and the target gene phosphatase and tensin homolog (PTEN) was examined through Luciferase reporter assay.

RESULTS

Compared with that in the Sham operation (Sham) group, the miR-19a expression in rat myocardial tissues in the MIR group was significantly increased (p<0.05). Compared with those in the miR-negative control (miR-NC) group, the messenger RNA (mRNA) and protein expressions of PTEN in the miR-19a group were notably decreased (p<0.05). In comparison with the miR-NC group, miR-19a group had elevated expression of phosphorylated protein kinase B (p-Akt) (p<0.05). The Luciferase reporter gene assay manifested the direct binding of miR-19a to PTEN mRNA.

CONCLUSIONS

MiR-19a inhibits the PTEN expression by directly binding to the 3'-UTR of PTEN mRNA, thus activating the Akt/p-Akt signaling pathway to suppress the apoptosis of myocardial cells in MIR injury.

NV center pumped and enhanced by nanowire ring resonator laser to integrate a 10 μm-scale spin-based sensor structure

In this work, we propose a 10 μm-scale spin-based sensor structure, which mainly consists of a nanowire (NW) ring resonator laser, nitrogen-vacancy (NV) defects in a nanodiamond (ND) and a microwave (MW) antenna. The NW laser was bent into a ring with a gap to pump the NV defects in the ND which was assembled in the gap with the diameter of ∼8 μm. And the fluorescent light of NV defects was enhanced by the NW ring resonator about 8 times. Furthermore, the NW laser pulse was produced by the optical switch and a simple plus-sequences was designed to get the Rabi oscillation signal. Based on the Rabi oscillation, a Ramsey-type sequence was used to detect the magnetic field with the sensitivity of 83 nT √Hz^-1 for our 10 μm-scale spin-based sensor structure. It proves the spin state in our structure allows for coherent spin manipulation for more complex quantum control schemes. And our structure fulfills the fundamental requirements to develop chip-scale spin-based sensors.

Correlation between Sarcopenia and Arteriosclerosis in Elderly Community Dwellers: A Multicenter Study

BACKGROUND

Evidence suggests that arteriosclerosis and sarcopenia (decreased muscle mass) share some of their many causes. However, after controlling for confounding factors, it is unclear whether the presence of arteriosclerosis correlates with sarcopenia.

OBJECTIVES

The aim of this paper is to explore whether sarcopenia is associated with arteriosclerosis.

DESIGN

A multicenter cross-sectional community-based study.

MATERIALS AND METHODS

A total of 2511 elderly subjects from six Chinese community health service centers in Anhui province were surveyed through an e-health promotion system to collect basic data and measurements of brachial-ankle pulse wave (baPWV), body composition, and handgrip strength (HGS). Pearson's correlation and binary logistic regression analyses were performed to identify associations between sarcopenia and high baPWV.

RESULTS

The prevalence rates of sarcopenia were 12.9% in men and 15.3% in women according to the 2019 standard of Asian Working Group for Sarcopenia. Among subjects with high baPWV, the proportion of sarcopenia was higher compared to those with normal baPWV (men: 17.7% vs. 3.7%; women: 20.4% vs. 4.9%, both p<0.001). Binary logistic regression analysis revealed that sarcopenia was associated with high baPWV (p<0.0001, odds ratio=1.619) after adjusting for confounding factors. HGS slightly and negatively correlated with baPWV (-0.19 in men and -0.18 in women).

CONCLUSIONS

The intertwined pathophysiological mechanisms shared by arteriosclerosis and sarcopenia are potential targets for future interventions to reduce morbimortality in subjects with both disorders. Upcoming prospective studies and clinical trials are expected to advance these findings.

Mental health problems and correlates among 746 217 college students during the coronavirus disease 2019 outbreak in China

AIMS

Coronavirus disease 2019 (COVID-19) pandemic is a major public health concern all over the world. Little is known about the impact of COVID-19 pandemic on mental health in the general population. This study aimed to assess the mental health problems and associated factors among a large sample of college students during the COVID-19 outbreak in China.

METHODS

This cross-sectional and nation-wide survey of college students was conducted in China from 3 to 10 February 2020. A self-administered questionnaire was used to assess psychosocial factors, COVID-19 epidemic related factors and mental health problems. Acute stress, depressive and anxiety symptoms were measured by the Chinese versions of the impact of event scale-6, Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7, respectively. Univariate and hierarchical logistic regression analyses were performed to examine factors associated with mental health problems.

RESULTS

Among 821 218 students who participated in the survey, 746 217 (90.9%) were included for the analysis. In total, 414 604 (55.6%) of the students were female. About 45% of the participants had mental health problems. The prevalence rates of probable acute stress, depressive and anxiety symptoms were 34.9%, 21.1% and 11.0%, respectively. COVID-19 epidemic factors that were associated with increased risk of mental health problems were having relatives or friends being infected (adjusted odds ratio = 1.72-2.33). Students with exposure to media coverage of the COVID-19 ≥3 h/day were 2.13 times more likely than students with media exposure <1 h/day to have acute stress symptoms. Individuals with low perceived social support were 4.84-5.98 times more likely than individuals with high perceived social support to have anxiety and depressive symptoms. In addition, senior year and prior mental health problems were also significantly associated with anxiety or/and depressive symptoms.

CONCLUSIONS

In this large-scale survey of college students in China, acute stress, anxiety and depressive symptoms are prevalent during the COVID-19 pandemic. Multiple epidemic and psychosocial factors, such as family members being infected, massive media exposure, low social support, senior year and prior mental health problems were associated with increased risk of mental health problems. Psychosocial support and mental health services should be provided to those students at risk.

[Observation and analysis of lens turbidity lesion induced by low intensity 635 nm laser radiation]

Objective: To study the characteristics of the lens turbidity after long-term exposure to low intensity 635nm laser. Methods: Cluster sampling method was adopted to select 812 employees in a laser leveler workshop in a city of Guangdong Province from January 2014 to December 2018. They were divided into the control group, diffuse reflection (DR) group and direct vision (DV) group for retrospective observation and analysis of lens turbidity. The laser irradiation intensity of each group was investigated, the position and shape of lens opacity were analyzed, and the influencing factors were statistically analyzed with the repeated measurement data of dichotomy. Results: The laser irradiance and radiant exposure of DV group were between 0.72×10(-4) and 9.92×10(-4) mW/cm(2) and between 2.61×10(-2) and 1.53 J/cm(2), respectively. The subjects were mainly diagnosed with lens turbidity lesion, especially for the DV group. Most of lesions occurred in the pole and periphery of the anterior cortex. The lesions exhibited multipoint patterns with greyish white color. The turbidity rates in DV group (before work and work for 1, 2, 3 years) were 0%, 1.99% (8/402) , 4.98% (20/402) and 6.72% (27/402) , respectively, in the order of observation points. The statistical analysis of single factor effect showed that the turbidity rate was higher in DV group and higher in the second year in the DV group (P<0.01) . Multi-factor analysis of the laser effect on the lens showed that the main effect between groups, between the observation point were statistically significant (P<0.05) , but no statistical significance in the interaction between group×observation points (P>0.05) . Conclusion: Lens turbidity lesion can be caused by long-term exposure to low intensity 635 nm laser, so the product safety classification should be strictly strengthened. It is necessary to strengthen the protection of laser photochemical damage in the production process.

von Willebrand factor promotes platelet-induced metastasis of osteosarcoma through activation of the VWF-GPIb axis

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Immunohistochemistry results directly show VWF is increased during tumor progression.

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VWF is expressed as low molecular weight multimer in OS cell line SAOS2.

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VWF promotes platelet-induced metastasis of OS through VWF-GPIb pathway.

von Willebrand factor (VWF) is exclusively expressed in endothelial cells (ECs) and megakaryocytes, which plays a crucial role in the initiation of arterial thrombosis. Recent studies have shown that VWF is also expressed in osteosarcoma (OS) cells and participates in adhesion of cancer cells to platelets, thus promoting metastasis of OS cells. However, it is unclear how OS cell-derived VWF-platelet interaction contributes to the metastasis of OS. We hypothesized that the interaction is mediated by the binding between VWF A1 and GPIbα of platelets, a molecular mechanism similar to that of thrombosis. The increased expression of VWF in SAOS2 cells may contribute to the enhancement of platelet adhesion through the VWF-GPIb pathway, which could promote the migration and invasion capacities of SAOS2 cells in vitro. Antibodies that block the pathway could significantly inhibit the platelet-induced metastasis of OS cells. Our results suggest a theoretical basis for the development of new anti-OS metastasis drugs, and further enrich the mechanism of OS metastasis.

TPH: A Three-Phase-based Heuristic algorithm for influence maximization in social networks

Influence maximization is a fundamental problem, which is aimed to specify a small number of individuals as seed set to influence the largest number of individuals under a certain influence cascade model. Most existing works on influence maximization may have either high effectiveness or good efficiency,which can not balance both the effectiveness and efficiency. One of the reason is that they do not consider the effect of influence overlap on the effectiveness. That is, these works ignore the phenomenon that the same set of nodes may be influenced by a subset of different influential nodes. To tackle the effectiveness of heuristic algorithm, we propose a three-phase-based heuristic algorithm, called Three-Phase-based Heuristic (TPH), which uses K-shell method to find influential nodes firstly. Moreover, we utilize weighed degree to make up for the coarse-grained of K-shell method. At last, we take advantage of similarity index to reduce the effect of influence overlap by covering the similar neighbor nodes with low influence. Furthermore, exhaustive experiments indicate that the proposed algorithm outperforms the other baseline algorithms in the aspects of influence spread and running time.