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Following myocardial ischemic injury, the most effective clinical intervention is timely restoration of blood perfusion to ischemic but viable myocardium to reduce irreversible myocardial necrosis, limit infarct size, and prevent cardiac insufficiency. However, reperfusion itself may exacerbate cell death and myocardial injury, a process commonly referred to as ischemia/reperfusion (I/R) injury, which primarily involves cardiomyocytes and cardiac microvascular endothelial cells (CMECs) and is characterized by myocardial stunning, microvascular damage (MVD), reperfusion arrhythmia, and lethal reperfusion injury. MVD caused by I/R has been a neglected problem compared to myocardial injury. Clinically, the incidence of microvascular angina and/or no-reflow due to ineffective coronary perfusion accounts for 5–50% in patients after acute revascularization. MVD limiting drug diffusion into injured myocardium, is strongly associated with the development of heart failure. CMECs account for > 60% of the cardiac cellular components, and their role in myocardial I/R injury cannot be ignored. There are many studies on microvascular obstruction, but few studies on microvascular leakage, which may be mainly due to the lack of corresponding detection methods. In this review, we summarize the clinical manifestations, related mechanisms of MVD during myocardial I/R, laboratory and clinical examination means, as well as the research progress on potential therapies for MVD in recent years. Better understanding the characteristics and risk factors of MVD in patients after hemodynamic reconstruction is of great significance for managing MVD, preventing heart failure and improving patient prognosis. [ABSTRACT FROM AUTHOR]

The control of axillary bud development after removing the terminal buds (topping) of plants is a research hotspot, and the control of gene expression, like switching on and off, allows us to further study biological traits of interest, such as plant branching and fertility. In this study, a toxin gene control system for plants based on dexamethasone (DEX) induction was constructed, and the positive transgenic tobacco exhibited growth retardation in the application area (axillary bud). The expression level of the lethal Diphtheria toxin A (DTA) gene under different DEX concentrations at different application days was analyzed. The highest expression levels appeared at 5 days after the leaf injection of DEX. The DTA transcripts were induced by 5 µM DEX and peaked in response to 50 µM DEX at 5 days after leaf injection. Here, a chemical induction system, combined with a toxin gene, were used to successfully control the growth of tobacco axillary buds after topping. The DTA expression system under DEX induction was sensitive and efficient, therefore, can be used to control axillary bud growth and development in tobacco. [ABSTRACT FROM AUTHOR]

PCSK9 plays a crucial role in lipid metabolism. This case–control study explored the associations of novel single nucleotide polymorphisms (SNPs) of the PCSK9 gene with coronary artery disease (CAD) (≥ 1 coronary artery stenosis ≥ 50%) and its risk factors in the Han population in Xinjiang, China. Four tag SNPs (rs11583680, rs2483205, rs2495477 and rs562556) of the PCSK9 gene were genotyped in 950 CAD patients and 1082 healthy controls. The distributions of genotypes in rs2483205 and rs562556 were significantly different between the groups (all p < 0.05). The TT genotype of rs2483205, GG genotype of rs562556, and their H4 (T-G) haplotype were associated with CAD [odds ratio (OR) 0.65, confidence interval (CI) 0.45–0.95, p = 0.024; 0.63, 0.45–0.90, p = 0.011; 0.50, 0.35–0.70, p < 0.001, respectively]. Additionally, the model (TT + CT vs. CC) of rs2483205 was associated with increased risk of obesity, and the G allele of rs562556 was associated with lower low-density lipoprotein cholesterol (LDL-C), blood glucose, body mass index (BMI), and mean platelet volume (MPV) (all p < 0.05). rs2483205, rs562556, and their H4 haplotype of the PCSK9 gene were associated with CAD. Additionally, rs2483205 is associated with obesity, and rs562556 is associated with LDL-C, blood glucose, BMI, and MPV. [ABSTRACT FROM AUTHOR]

Macrophage migration inhibitory factor (MIF) is an essential mediator of atherosclerotic plaque progression and instability leading to intracoronary thrombosis, therefore contributing to coronary artery disease (CAD). In this study, we investigated the relationship between MIF gene polymorphism and CAD in Chinese Han population. Three single nucleotide polymorphisms (SNP, rs755622, rs1007888 and rs2096525) of MIF gene were genotyped by TaqMan genotyping assay in 1120 control participants and 1176 CAD patients. Coronary angiography was performed in all CAD patients and Gensini score was used to assess the severity of coronary artery lesions. The plasma levels of MIF and other inflammatory mediators were measured by ELISA. The CAD patients had a higher frequency of CC genotype and C allele of rs755622 compared with that in control subjects (CC genotype: 6.5% vs. 3.9%, P = 0.008, C allele: 24.0% vs. 20.6%, P = 0.005). The rs755622 CC genotype was associated with an increased risk of CAD (OR: 1.804, 95%CI: 1.221–2.664, P = 0.003). CAD patients with a variation of rs755622 CC genotype had significantly higher Gensini score compared with patients with GG or CG genotype (all P < 0.05). In addition, the circulating MIF level was highest in CAD patients carrying rs755622 CC genotype (40.7 ± 4.2 ng/mL) and then followed by GC (37.9 ± 3.4 ng/mL) or GG genotype (36.9 ± 3.7 ng/mL, all P < 0.01). Our study showed an essential relationship between the MIF gene rs755622 variation and CAD in Chinese Han population. Individuals who carrying MIF gene rs755622 CC genotype were more susceptible to CAD and had more severe coronary artery lesion. This variation also had a potential influence in circulating MIF levels. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) are transcripts longer than 200 nucleotides. Some lncRNAs are related to acute myocardial infarction (AMI) and can serve as blood-based biomarkers for AMI detection. To identify whether new lncRNAs participate in AMI, the expression of lncRNAs and mRNAs was analysed by microarray analysis (Agilent human array) with the limma package in R in two series: five paired peripheral blood mononuclear cell (PBMC) samples and four paired plasma samples from different AMI patients. In PBMCs, a total of 2677 upregulated and 458 downregulated lncRNAs were significantly differentially expressed; additionally, 1168 mRNAs were upregulated and 1334 mRNAs were downregulated between the AMI patients and controls. In plasma, we found 41 upregulated and 51 downregulated lncRNAs that were differentially expressed, as well as 9 mRNAs that were upregulated and 9 mRNAs that were downregulated among the two groups. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using the clusterProfiler package in R, and differentially expressed mRNAs were functionally annotated. The top differentially expressed mRNAs were associated with circadian rhythm, the NF-kB pathway, the p53 pathway and the metabolism pathway. We further performed target gene prediction and coexpression analysis and revealed the interrelationships among the significantly differentially expressed lncRNAs and mRNAs. The expression of four lncRNAs (uc002ddj.1, NR_047662, ENST00000581794.1 and ENST00000509938.1) was validated in the newly diagnosed AMI and control groups by quantitative real-time PCR (qRT-PCR). Our study demonstrated that the clustered expression of lncRNAs between PBMCs and plasma showed tremendous differences. The newly screened lncRNAs may play indispensable roles in the development of AMI, although their biological functions need to be further validated. [ABSTRACT FROM AUTHOR]

Purpose: We investigated whether increased expression of activated mitogen-activated protein kinase (MAPK) kinases 1 (MEK1) restores ischemic post-conditioning (IPostC) protection in hypertrophic myocardium following ischemia/reperfusion (I/R) injury. Methods: C57Bl/6 mice received recombinant adeno-associated virus type 9 (rAAV9)-mediated activated MEK1 gene delivery systemically, then following the induction of cardiac hypertrophy via transverse aortic constriction for 4 weeks. In a Langendorff model, hypertrophic hearts were subjected to 40 min/60 min I/R or with IPostC intervention consisting of 6 cycles of 10 s reperfusion and 10 s no-flow before a 60-min reperfusion. Hemodynamics, infarct size (IS), myocyte apoptosis and changes in expression of reperfusion injury salvage kinase (RISK) pathway were examined. Results: rAAV9-MEK1 gene delivery led to a 4.3-fold and 2.7-fold increase in MEK1 mRNA and protein expression in the heart versus their control values. I/R resulted in a larger IS in hypertrophic than in non-hypertrophic hearts (52.3 ± 4.7% vs. 40.0 ± 2.5%, P < 0.05). IPostC mediated IS reduction in non-hypertrophic hearts (27.6 ± 2.6%, P < 0.05), while it had no significant effect in hypertrophic hearts (46.5 ± 3.1%, P=NS) compared with the IS in non-hypertrophic or hypertrophic hearts subjected to I/R injury only, respectively. Hemodynamic decline induced by I/R was preserved by IPostC in non-hypertrophic hearts but not in hypertrophic hearts. rAAV9-MEK1 gene delivery restored IPostC protection in hypertrophic hearts evidenced by reduced IS (32.0 ± 2.8% vs. 46.5 ± 3.1%) and cardiac cell apoptosis and largely preserved hemodynamic parameters. These protective effects were associated with significantly increased phosphorylation of ERK1/2 and ribosomal protein S6 kinases (p70S6K), but it had no influence on Akt and glycogen synthase kinase-3β. Conclusion: These results demonstrated that rAAV9-mediated activated MEK1 expression restores IPostC protection in the hypertrophic heart against I/R injury through the activation of ERK pathway. [ABSTRACT FROM AUTHOR]

Macrophage migration inhibitory factor (MIF) has been recognized as a major player in the pathogenesis of atherosclerosis. This study determined the association between polymorphisms of MIF gene and acute coronary syndrome (ACS). The polymorphism of MIF gene (rs755622, rs1007888 and rs2096525) was analyzed in 1153 healthy controls and 699 ACS cases in Chinese Han population. Plasma MIF level was also measured in part of ACS patients (139/19.9%) and healthy controls (129/11.2%) randomly. Most participants including healthy controls and ACS patients carried rs755622 GG (63.1% vs. 56.7%) and CG genotypes (33.1% vs. 38.9%) and G allele of rs755622 (79.6% vs. 76.1%, respectively), while CC genotype (3.8% vs. 4.4%) and C allele (20.4% vs. 23.9%) carriers were the lowest. Multivariate logistic regression analysis showed that carriers with rs755622 C allele had a higher risk of ACS compared to other genotypes (AOR = 1.278, 95% CI: 1.042–1.567). In addition, CC genotype carriers had the highest plasma levels of MIF than other genotype carriers. The MIF level in ACS patients with CC genotype was significantly higher than ACS patients carrying GG genotype and healthy controls carrying 3 different genotypes of MIF gene rs755622. Our findings indicate that MIF gene rs755622 variant C allele is associated with increased risk of ACS. Identification of this MIF gene polymorphism may help for predicting the risk of ACS. [ABSTRACT FROM AUTHOR]

Purpose: Inhibition of the renin-angiotensin system (RAS) is beneficial in patient management after myocardial infarction (MI). However, whether RAS inhibition also provides cardiac protection in the acute phase of MI is unclear. Methods: Male 129sv mice underwent coronary artery occlusion to induce MI, followed by treatment with losartan (L, 20 and 60 mg/kg), perindopril (P, 2 and 6 mg/kg), amlodipine (20 mg/kg as a BP-lowering agent) or vehicle as control. Drug effects on hemodynamics were examined. Effects of treatments on incidence of cardiac rupture, haematological profile, monocyte and neutrophil population in the spleen and the heart, cardiac leukocyte density, expression of inflammatory genes and activity of MMPs were studied after MI. Results: Incidence of cardiac rupture within 2 weeks was significantly and similarly reduced by both losartan (L) and perindopril (P) in a dose-dependent manner [75% (27/36) in vehicle, 40-45% in low-dose (L 10/22, P 8/20) and 16-20% (L 5/32, P 4/20) in high-dose groups, all P < 0.05]. This action was independent of their BP-lowering action, as amlodipine reduced BP to a similar degree without effect on rupture (70%, 21/30). Compared to the control group, high dose losartan and perindopril decreased counts of white blood cells, neutrophils and lymphocytes (all P < 0.05), and inhibited splenic monocyte and neutrophil release into the circulation. Consequently, monocyte, neutrophil and leukocyte infiltration, inflammatory gene expressions (IL-1β, IL-6, MMP9, MCP-1, TNF-α and TGFβ1) and activity of MMP2 and MMP9 in the infarct tissue were attenuated by losartan and/or perindopril treatment (all P < 0.05). Conclusions: RAS inhibition by losartan or perindopril prevented cardiac rupture at the acute phase of MI through blockade of splenic release of monocytes and neutrophils and consequently attenuation of systemic and regional inflammatory responses. [ABSTRACT FROM AUTHOR]

Cathay silver fir, Cathaya argyrophylla, is a national first-class protected species in China and honored as a 'living fossil' of the plant kingdom. Recently, a needle cast of Cathay silver fir of the Guangxi Zhuang Autonomous Region, China was investigated. This pathogen not only reduces the host ornamental value, but seriously affects the growth of this endangered plant. In this paper, the needle cast, formerly misidentified as Lophodermium pinastri, is identified as Lophodermium cathayae. L. cathayae differs morphologically from L. pinastri in many aspects, but particularly in anamorph morphology. An analysis of the internal transcribed spacer of rDNA shows that L. cathayae is closely related to L. pinastri and that further study is required in order to update the circumscription of L. pinastri. The fungal diversity conservation for new species L. cathayae is discussed. [ABSTRACT FROM AUTHOR]

When BALB/c mouse spleens were gently homogenized in saline, the resultant supernatant (without cells and tissue debris) contained significant amount of 28S and 18S ribosomal RNA, reaching up to 70% of the total spleen RNA. Haemoglobin assays indicated that less than 15% of the spleen cells were lysed during the homogenization process, indicating that the majority of the spleen `supernatant RNA' was from the extracellular space of the organ rather than released by the splenocytes as a consequence of grinding. Quantitative RNA analysis showed that the ratio of spleen supernatant RNA/total RNA of BALB/c mice was inversely correlated with age (from approximately 70% at 3 weeks to 45% at 6 months), but that of BXSB mice (an animal model for systemic lupus erythematosus) remained at about 70% irrespective of age. Methyl Green–Pyronin Y staining of paraffin sections of mouse spleen revealed that extracellular RNA was distributed mainly in the sinuses of the organ. Culture supernatants of apoptotic splenocytes contained significant amounts of RNA, suggesting that the extracellular RNA in the spleen might have come from apoptotic lymphocytes. This is supported by the fact that `thymus supernatant' also contained significant amount of RNA. A possible correlation between spleen extracellular RNA and autoimmune diseases is discussed. [ABSTRACT FROM AUTHOR]

Pyronin Y has long been used, in combination with other dyes such as Methyl Green, as a differential stain for nucleic acids in paraffin tissue sections. It also forms fluorescent complexes with double-stranded nucleic acids, especially RNA, enabling semi-quantitative analysis of cellular RNA in flow cytometry. However, the possibility of using pyronin Y as a fluorescent stain for paraffin tissue sections has rarely been investigated. We herein report that in sections stained with Methyl Green–pyronin Y, red blood cells, elastic fibre of blood vessels, zymogen granules of pancreatic acinar cells, surface membrane of heptocytes and kidney tubular cells showed strikingly strong green and/or red fluorescence, while the nuclei of cells appeared non-fluorescent. The use of confocal laser-scanning microscope greatly improved the resolution and selectivity of the fluorescent images. Staining with pyronin Y alone gave similar results in terms of fluorescence properties of the specimens. Pretreatment of paraffin sections with RNase significantly reduced cytoplasmic pyronin Y staining as judged by transmission light microscopy, but it had little effect on the fluorescence intensity of red blood cells, elastic fibres and zymogenbreak granules. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI), the leading cause of mortality and disability worldwide, is a disease in which multiple environmental and genetic factors are involved. Recently, researches suggested that insertion/deletion (ins/del) variation of NFKB1 gene rs28362491 is a functional polymorphism. In the present study, we aimed to explore the relation between variation of NFKB1 gene rs28362491 and MI by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) in 359 MI patients and 1085 control participants. Gensini score was used to evaluate the degree of coronary artery stenosis in MI patients. The plasma levels of interleukin-6 (IL-6), IL-8, malonaldehyde (MDA) and superoxide dismutase (SOD) were randomly measured by ELISA both in MI patients and control participants. We found that the detected frequencies of D allele (41.2% vs. 36.4%, P = 0.021) and DD genotype (17.5% vs. 12.0%, P = 0.022) were significantly higher in MI patients than in control participants. Compared with II or ID genotype carriers, the Gensini score in MI patients with DD genotype was 32–43% higher (both P < 0.001). Moreover, DD genotype carries had more diseased coronary arteries (P = 0.001 vs. II or ID genotype). Of note, IL-6 levels in MI patients carrying DD genotype were significantly higher than that in control participants and other genotype carriers in MI patients (both P < 0.05). In conclusion, NFKB1 gene rs28362491 DD genotype was associated with a higher risk of MI and more severe coronary artery lesion, which also had a potential influence on the level of inflammatory cytokine IL-6. [ABSTRACT FROM AUTHOR]

Microvascular obstruction (MVO) and leakage (MVL) forms a pivotal part of microvascular damage following cardiac ischemia–reperfusion (IR). We tested the effect of relaxin therapy on MVO and MVL in mice following cardiac IR injury including severity of MVO and MVL, opening capillaries, infarct size, regional inflammation, cardiac function and remodelling, and permeability of cultured endothelial monolayer. Compared to vehicle group, relaxin treatment (50 μg/kg) reduced no-reflow area by 38% and the content of Evans blue as a permeability tracer by 56% in jeopardized myocardium (both P < 0.05), effects associated with increased opening capillaries. Relaxin also decreased leukocyte density, gene expression of cytokines, and mitigated IR-induced decrease in protein content of VE-cadherin and relaxin receptor. Infarct size was comparable between the two groups. At 2 weeks post-IR, relaxin treatment partially preserved cardiac contractile function and limited chamber dilatation versus untreated controls by echocardiography. Endothelial cell permeability assay demonstrated that relaxin attenuated leakage induced by hypoxia-reoxygenation, H2O2, or cytokines, action that was independent of nitric oxide but associated with the preservation of VE-cadherin. In conclusion, relaxin therapy attenuates IR-induced MVO and MVL and endothelial leakage. This protection was associated with reduced regional inflammatory responses and consequently led to alleviated adverse cardiac remodeling. [ABSTRACT FROM AUTHOR]

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper. [ABSTRACT FROM AUTHOR]

Lactoferrin (LTF), an important first line defense molecule against infection, is a common target for humoral autoimmune reactions in humans. Since LTF is a multifunctional protein capable of activating innate immune cells via various surface receptors, we hypothesized that LTF-containing immune complexes (ICs) (LTF-ICs), likely formed in patients with high titer anti-LTF autoantibodies, could possess unique monocyte/macrophage-activating properties compared with other ICs. ELISA analysis on serum samples from rheumatoid arthritis (RA) patients (n = 80) and healthy controls (n = 35) for anti-LTF autoantibodies confirmed a positive correlation between circulating LTF-specific IgG and RA. ICs between human LTF and LTF-specific IgG purified from patient sera or immunized rabbits and mice, but not control ICs, LTF or Abs alone, elicited strong production of TNF-α and IL-1β by freshly fractionated human peripheral blood monocytes and monocytes-derived macrophages. Furthermore, LTF-ICs utilized both membrane-anchored CD14 and CD32a (FcγRIIa) to trigger monocyte activation in an internalization-, Toll-like receptor (TLR)4- and TLR9-dependent manner, and also that LTF-IC-induced cytokine production was blocked by specific inhibitors of caspase-1, NF-κB and MAPK. These results uncover a possible pathway for LTF-ICs perpetuating local inflammation and contributing to the pathogenesis of autoimmune diseases by triggering activation of infiltrating monocytes or tissue macrophages in vivo. [ABSTRACT FROM AUTHOR]