ObjectivesRecent studies have demonstrated the role of Cdr1as (or CiRS-7), one of the well-identified circular RNAs (circRNAs), as a miR-7a/b sponge or inhibitor in brain tissues or islet cells. This study aimed to investigate the presence of Cdr1as/miR-7a pathway in cardiomyocytes, and explore the mechanism underlying the function of miR-7a in protecting against myocardial infarction (MI)-induced apoptosis.MethodsMouse MI injury model was established and evaluated by infarct size determination. Real-time PCR was performed to quantify the expression of Cdr1as and miR-7a in cardiomyocytes. Cell apoptosis was determined by caspase-3 activity analysis and flow cytometry assays with Annexin V/PI staining. Transfection of Cdr1as overexpressing plasmid and miR-7a mimic were conducted for gain-of-function studies. Luciferase reporter assay and western blot analysis were performed to verity potential miR-7a targets.ResultsCdr1as and miR-7a were both upregulated in MI mice with increased cardiac infarct size, or cardiomyocytes under hypoxia treatment. Cdr1as overexpression in MCM cells promoted cell apoptosis, but was then reversed by miR-7a overexpression. The SP1 was identified as a new miR-7a target, in line with previously identified PARP, while miR-7a-induced decrease of cell apoptosis under hypoxia treatment was proven to be inhibited by PARP-SP1 overexpression. Moreover, Cdr1as overexpression in vivo increased cardiac infarct size with upregulated expression of PARP and SP1, while miR-7a overexpression reversed these changes.ConclusionsCdr1as also functioned as a powerful miR-7a sponge in myocardial cells, and showed regulation on the protective role of miR-7a in MI injury, involving the function of miR-7a targets, PARP and SP1.

This paper seeks to understand whether a catastrophic and urgent event, such as the first months of the COVID-19 pandemic, accelerates or reverses trends in international collaboration, especially in and between China and the United States. A review of research articles produced in the first months of the COVID-19 pandemic shows that COVID-19 research had smaller teams and involved fewer nations than pre-COVID-19 coronavirus research. The United States and China were, and continue to be in the pandemic era, at the center of the global network in coronavirus related research, while developing countries are relatively absent from early research activities in the COVID-19 period. Not only are China and the United States at the center of the global network of coronavirus research, but they strengthen their bilateral research relationship during COVID-19, producing more than 4.9% of all global articles together, in contrast to 3.6% before the pandemic. In addition, in the COVID-19 period, joined by the United Kingdom, China and the United States continued their roles as the largest contributors to, and home to the main funders of, coronavirus related research. These findings suggest that the global COVID-19 pandemic shifted the geographic loci of coronavirus research, as well as the structure of scientific teams, narrowing team membership and favoring elite structures. These findings raise further questions over the decisions that scientists face in the formation of teams to maximize a speed, skill trade-off. Policy implications are discussed.

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After the initial shock of the early months of the global COVID-19 pandemic, international collaboration in COVID-19 research continues to show aberrant patterns compared to coronavirus research in pre-COVID times. The most affected nations tend to produce the greatest number of coronavirus articles, with output closely coupled to the rate of infection. COVID-19 research has fewer nations and smaller teams than pre-COVID research, a trend which intensifies throughout the pandemic. The United States remains the single largest contributor to the global publication output, but contrary to China’s dominance in the initial months of the pandemic, China’s contribution falls as the national COVID-19 caseload drops. China-USA collaborations drop as the pandemic continues, perhaps due to China’s reduced rate of publication on the topic, and perhaps due to political obstacles, or a combination of these factors.

Genetically engineered (GE) rice endogenous epsps (5-enolpyruvoylshikimate-3-phosphate synthase) gene overexpressing EPSPS can increase glyphosate herbicide-resistance of cultivated rice. This type of epsps transgene can enhance the fecundity of rice crop-weed hybrid offspring in the absence of glyphosate, stimulating great concerns over undesired environmental impacts of transgene flow to populations of wild relatives. Here, we report the substantial alteration of phenology and fitness traits in F1-F3 crop-wild hybrid descendants derived from crosses between an epsps GE rice line and two endangered wild rice (Oryza rufipogon) populations, based on the common-garden field experiments. Under the glyphosate-free condition, transgenic hybrid lineages showed significantly earlier tillering and flowering, as well as increased fecundity and overwintering survival/regeneration abilities. In addition, a negative correlation was observed between the contents of endogenous EPSPS of wild, weedy, and cultivated rice parents and fitness differences caused by the incorporation of the epsps transgene. Namely, a lower level of endogenous EPSPS in the transgene-recipient populations displayed a more pronounced enhancement in fitness. The altered phenology and enhanced fitness of crop-wild hybrid offspring by the epsps transgene may cause unwanted environmental consequences when this type of glyphosate-resistance transgene introgressed into wild rice populations through gene flow.

Transgene introgression into crop weedy/wild relatives can provide natural selective advantages, probably causing undesirable environmental impact. The advantages are likely associated with factors such as transgenes, selective pressure, and genetic background of transgene recipients. To explore the role of the environment and background of transgene recipients in affecting the advantages, we estimated the fitness of crop‐weed hybrid lineages derived from crosses between marker‐free insect‐resistant transgenic (Bt/CpTI) rice with five weedy rice populations under varied insect pressure. Multiway anova indicated the significant effect of both transgenes and weedy rice genotypes on the performance of crop‐weed hybrid lineages in the high‐insect environment. Increased fecundity was detected in most transgene‐present F1 and F2 hybrid lineages under high‐insect pressure, but varied among crop‐weed hybrid lineages with different weedy rice parents. Increased fecundity of transgenic crop‐weed hybrid lineages was associated with the environmental insect pressure and genotypes of their weedy rice parents. The findings suggest that the fitness effects of an insect‐resistant transgene introgressed into weedy populations are not uniform across different environments and genotypes of the recipient plants that have acquired the transgene. Therefore, these factors should be considered when assessing the environmental impact of transgene flow to weedy or wild rice relatives.

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AIM: To investigate the relationship between gallbladder stone disease (GSD) and single nucleotide polymorphisms of cholesterol 7α-hydroxylase (CYP7A) gene promoter, apolipoprotein (APO) B gene exon 26, APOE gene exon 4 or microsatellite polymorphism of low density lipoprotein receptor (LDLR) gene exon 18. METHODS:Genotypes of CYP7A, APOB, APOE and LDLR genes were determined in 105 patients with GSD diagnosed by B-mode ultrasonography and 274 control subjects. Serum lipids were analyzed with HITACHI 7060 automaic biochemical analyzer. RESULTS:Body mass index (BMI) was significantly higher in patients with GSD (24.47±3.09) than in controls (23.50±2.16). Plasma total cholesterol was lower in patients with GSD (4.66±0.92 mmol/L) than in controls (4.91±0.96 mmol/L), P<0.01 after adjusted for age, sex and BMI. The significantly higher frequency of A allele of CYP7A gene polymorphism and X+ allele of APOB gene polymorphism was seen in GSD patients. Percentages of A allele in patients and controls were 62.86% and 54.38% (P <0.05) and those of X+ allele 8.57% and 4.01% (P<0.01). Subjects with A allele had significantly lower plasma total cholesterol and LDL cholesterol than subjects with CC homozygote. In a multiple variable logistic regression model, the BMI (OR=1.13, 95% CI: 1.05-1.22), A allele (OR=1.48, 95% CI: 1.05-2.09) and X+ allele (OR=2.28, 95% CI: 1.14-4.59) were positively associated with GSD (P <0.05). Plasma total cholesterol (OR=0.69, 95% CI: 0.64-0.74) was negatively related to GSD (P<0.05). CONCLUSION:With an association analysis, it was determined that A allele of CYP7A gene and X+ allele of APOB gene might be considered as risk genes for GSD. These alleles are related with differences of serum lipids among subjects. Multiple-variable logistic regression model analysis showed that besides BMI, GSD was affected by polygenetic factors. But the mechanism for these two alleles responsible for GSD requires further investigations.