Mesenchymal stem cells with overexpression of midkine enhance cell survival and attenuate cardiac dysfunction in a rat model of myocardial infarction

Introduction. Elevated midkine (MK) expression may contribute to ventricular remodeling and ameliorate cardiac dysfunction after myocardial infarction (MI). Ex vivo modification of signaling mechanisms in mesenchymal stem cells (MSCs) with MK overexpression may improve the efficacy of cell-based therapy. This study sought to assess the safety and efficacy of MSCs with MK overexpression transplantation in a rat model of MI. Methods. A pLenO-DCE vector lentivirus encoding MK was constructed and infected in MSCs. MSC migration activity and cytoprotection was examined in hypoxia-induced H9C2 cells using transwell insert in vitro. Rats were randomized into five groups: sham, MI plus injection of phosphate buffered saline (PBS), MSCs, MSCs-green fluorescent protein (MSCs-GFP) and MSCs-MK, respectively. Survival rates were compared among groups using log-rank test and left ventricular function was measured by echocardiography at baseline, 4, 8 and 12 weeks. Results: Overexpression of MK partially prevented hypoxia-induced MSC apoptosis and exerted MSC cytoprotection to anoxia induced H9C2 cells. The underlying mechanisms may be associated with the increased mRNA and protein levels of vascular endothelial growth factor (VEGF), transformation growth factor-β (TGF-β), insulin-like growth factor 1 (IGF-1) and stromal cell-derived factor 1 (SDF-1a) in MSCs-MK compared with isolated MSCs and MSCs-GFP. Consistent with the qPCR results, the culture supernatant of MSCs-MK had more SDF-1a (9.23 ng/ml), VEGF (8.34 ng/ml) and TGF-β1 (17.88 ng/ml) expression. In vivo, a greater proportion of cell survival was observed in the MSCs-MK group than in the MSCs-GFP group. Moreover, MSCs-MK administration was related to a significant improvement of cardiac function compared with other control groups at 12 weeks. Conclusions: Therapies employing MSCs with MK overexpression may represent an effective treatment for improving cardiac dysfunction and survival rate after MI

2bRAD-M reveals the difference in microbial distribution between cancerous and benign ovarian tissues

The development of ovarian cancer is closely related to various factors, such as environmental, genetic and microbiological factors. In previous research, bacteria were identified in human tumors by 16S rRNA sequencing. However, the microbial biomass in tumor tissue is too low and cannot be accurately identified by 16S rRNA sequencing. In our study, we employ 2bRAD sequencing for Microbiome (2bRAD-M), a new sequencing technology capable of accurately characterizing the low biomass microbiome (bacteria, fungi and archaea) at species resolution. Here we surveyed 20 ovarian samples, including 10 ovarian cancer samples and 10 benign ovarian samples. The sequencing results showed that a total of 373 microbial species were identified in both two groups, of which 90 species shared in the two groups. The Meta statistic indicated that Chlamydophila_abortus and CAG-873_sp900550395 were increased in the ovarian cancer tissues, while Lawsonella_clevelandensis_A, Ralstonia_sp001078575, Brevundimonas_aurantiaca, Ralstonia_sp900115545, Ralstonia_pickettii, Corynebacterium_kefirresidentii, Corynebacterium_sp000478175, Brevibacillus_D_fluminis, Ralstonia_sp000620465, and Ralstonia_mannitolilytica were more abundant in the benign ovarian tissues. This is the first use of 2bRAD-M technique to provide an important hint for better understanding of the ovarian cancer microbiome

Double Disadvantages:A Study of Ethnic and Hukou Effects on Class Mobility in China (1996-2014)

This paper examines the ethnic and household registration system (hukou) effects on intergenerational social mobility for men in China. Using national representative surveys covering almost two decades (1996–2014), we assess both absolute and relative rates of mobility by ethnicity and hukou origin. With regard to absolute mobility, we find that minority men had significantly lower rates of total and upward mobility than Han men, and those from rural hukou origins faced more unfavourable chances. With regard to relative mobility, we find men of rural ethnic origins significantly less likely to inherit their parental positions. Even with parental and own educational qualifications and party memberships controlled for, we still find ethnic minority men of rural hukou origins behind others in access to professional-managerial positions. Overall, our findings suggest that the preferential policies have largely removed the ethnic differences in the urban sector but ethnic minority men from rural hukou origins are faced with double disadvantages: in addition to the inequality of opportunity rooted in the institutional divide which they share with the majority group from similar backgrounds, they face much greater inequalities in conditions, namely, in having poorer socio-economic and cultural resources

Differential Acculturation: A Study of Well-Being Differences in Intergenerational Social Mobility between Rural and Urban China

This article examines the effects of China’s household registration (hukou) system, which divides the population into rural and urban sectors with differential benefits and entitlements, on the link between intergenerational social mobility and people’s well-being. Using China General Social Surveys of 2005 and 2011, we find that upward mobility has a similarly positive effect in the urban and the rural sectors but downward mobility has a markedly negative effect chiefly in the rural sector. We propose a thesis of ‘asymmetrical permeability’ to account for the findings. In the context of rapid economic development and staggering institutional reform, the upwardly mobile in both sectors enjoy ample socio-economic resources as provided by the advantaged destination classes whereas the downwardly mobile depend very much on the hukou status they have. In the urban but not rural sector, families in advantaged positions are able to protect the downwardly mobile offspring in their well-being. It is therefore the differences in the hukou system that explain the differential acculturation

Full Aeroelastic Model Testing for Examining Wind-Induced Vibration of a 5,000 m Spanned Suspension Bridge

This paper presents an experimental investigation on wind-induced vibrations of a suspension bridge with ultimate main span length, including flutter and buffeting. Since the upper limit of a suspension bridge's main span can reach more than 5,000 m based on strength and weight of steel main cables, a feasible prototype with a span arrangement of 2,000 + 5,000 + 2,000 m has been proposed. In order to improve flutter stability, a twin box girder has been designed with a 40 m slot in center and two 20 m wide decks suspended by four main cables. Its full aeroelastic model was designed and manufactured with the geometrical scale of 1:620, and the wind tunnel testing was carried out under smooth flows and turbulent flows for different angles of attack. A big difference in critical flutter speed was found between the proposed slotted girder and corresponding slot-sealed girder, which verifies the necessity of a widely-slotted (WS) twin box girder for a super-long suspension bridge. Among three angles of attack, the critical flutter speed under smooth flow has the maximum value of 80.9 m/s at −3° and the minimum value of 51.4 m/s at 3°. On-coming turbulence will not only cause buffeting responses but also influence the critical flutter speed in an unfavorable way

The Discussion of Wind-induced Interference Effects of Large Cooling Towers Considering Wind Direction

This paper was reviewed and accepted by the APCWE-IX Programme Committee for Presentation at the 9th Asia-Pacific Conference on Wind Engineering, University of Auckland, Auckland, New Zealand, held from 3-7 December 2017

Inter- and intra-generational social mobility effects on subjective well-being - Evidence from mainland China

This paper contributes to the literature on well-being research by showing the distinct impacts of inter- and intra-generational social mobility on subjective well-being in mainland China. Based on the China General Social Surveys of 2006, we used diagonal reference modelling and other regression methods to assess the effects of social mobility on well-being. We found that well-being was associated with changes in class positions. In both inter- and intra-generational mobility trajectories, moving upward into a higher position was beneficial for people's well-being whereas different consequences were found for downward mobility: in the case of intergenerational mobility, downward mobility into the manual class did not have a marked effect on people's well-being as the downwardly mobile from privileged backgrounds held the prospect of counter-mobility at early career stages and inherited valuable resources; but downward mobility in one's own career life was rather detrimental to subjective well-being, as the downwardly mobile had to bear not only the material disadvantages found in the lower position, but also the psychological effects ensuing from the downward trajectory. We conclude that while those experiencing downward intergenerational mobility may resort to family advantages to help maintain their well-being levels, a similar trajectory in one's own career life may have a direct negative consequence