Impact of renin-angiotensin system inhibitors on long-term clinical outcomes of patients with rheumatic heart disease.

AIMS: Rheumatic heart disease (RHD) remains a major global health problem. Renin-angiotensin-aldosterone system inhibitors (RAASi) are commonly administered in the treatment of cardiovascular disease, but its role in RHD patients is still limited. We performed a retrospective study to determine the effect of RAASi on long-term outcomes for RHD patients. METHODS AND RESULTS: A 1:1 propensity score matching was implemented to balance baseline characteristics between groups RAASi and non-RAASi. Cox proportional hazards regression model was used to investigate the associations of RAASi with the risks of all-cause mortality, cardiovascular death (CVD), and cerebrovascular death. Binary logistic regression analysis was used to evaluate the associations of RAASi with the risks of 1, 3, and 5 year heart failure (HF) rehospitalization, new-onset atrial fibrillation (AF), and new-onset stroke. A total of 734 RHD patients were enrolled as study participants; nearly half of these participants had combined valve damage (54.4%), worse New York Heart Association functional class status (III and IV, 55.2%), surgical treatment (54.2%), and AF (65.0%). After propensity score matching, 514 RHD patients were finally analysed. RAASi treatment was associated with decreased risks of all-cause mortality [adjusted hazard ratio (HR) = 0.52, 95% confidence interval (CI): 0.37-0.73, P < 0.001], CVD (adjusted HR = 0.48, 95% CI: 0.30-0.76, P = 0.002), and cerebrovascular death (adjusted HR = 0.22, 95% CI: 0.08-0.60, P = 0.003). Further subgroup analysis showed that RAASi treatment was associated with decreased risks of all-cause mortality (adjusted HR = 0.50, 95% CI: 0.31-0.79, P = 0.004), CVD (adjusted HR = 0.48, 95% CI: 0.25-0.91, P = 0.025), and cerebrovascular death (adjusted HR = 0.19, 95% CI: 0.05-0.65, P = 0.008) in RHD patients without surgical treatment, and better effect was observed in RHD patients with surgical treatment on the risks of all-cause mortality (adjusted HR = 0.47, 95% CI: 0.26-0.85, P = 0.012) and CVD (adjusted HR = 0.43, 95% CI: 0.21-0.90, P = 0.024) except cerebrovascular death (adjusted HR = 0.52, 95% CI: 0.08-3.36, P = 0.491). RAASi treatment was associated with decreased HF rehospitalization risk of 1 year [adjusted odds ratio (OR) = 0.38, 95% CI: 0.23-0.61, P < 0.001], 3 year (adjusted OR = 0.43, 95% CI: 0.28-0.68, P < 0.001), and 5 year (adjusted OR = 0.48, 95% CI: 0.30-0.77, P = 0.002) as well as new-onset AF risk (adjusted OR = 0.38, 95% CI: 0.21-0.68, P = 0.001). RAASi treatment had nothing to do with new-onset stroke risk (adjusted OR = 0.80, 95% CI: 0.47-1.38, P = 0.428). CONCLUSION: Renin-angiotensin-aldosterone system inhibitor treatment was significantly associated with decreased risks of mortality, HF rehospitalization, and new-onset AF in RHD patients in median 5.9 year follow-up.

Aerosol and Surface Distribution of Severe Acute Respiratory Syndrome Coronavirus 2 in Hospital Wards, Wuhan, China, 2020.

To determine distribution of severe acute respiratory syndrome coronavirus 2 in hospital wards in Wuhan, China, we tested air and surface samples. Contamination was greater in intensive care units than general wards. Virus was widely distributed on floors, computer mice, trash cans, and sickbed handrails and was detected in air ≈4 m from patients.

A study of blood soluble P-selectin, fibrinogen, and von Willebrand factor levels in idiopathic and lone atrial fibrillation.

AIMS: A prothrombotic state with elevated levels of soluble P-selectin (sP-sel), fibrinogen, von Willebrand factor (vWf), and other haemostatic indices has been reported in some patients with atrial fibrillation (AF). Whether these changes are due to AF itself or coexistent cardiovascular diseases remains a matter of debate. Therefore, in the present study, the differences in plasma levels of sP-sel, fibrinogen, and vWf between patients with idiopathic/lone AF and sex-, age-, and risk factor-matched controls were investigated to determine whether AF itself might be associated with a hypercoagulable state. METHODS AND RESULTS: Ninety consecutive patients (63 males, 54.1 ± 10.1 years) with idiopathic AF were studied, 60 (43 males, 48.8 ± 7.5 years) of whom were diagnosed as lone AF. Plasma sP-sel and vWf were measured by enzyme-linked immunosorbent assay. Plasma fibrinogen was measured by chromometry. These indices in AF patients were compared with those in sex-, age- and risk factor-matched controls. Compared with the controls, patients with idiopathic AF had higher levels of sP-sel (AF vs. control: 33.4 ± 7.4 vs. 29.2 ± 6.5 ng/mL, P < 0.001) and fibrinogen (AF vs. control: 3.3 ± 0.9 vs. 3.0 ± 0.6 g/L, P = 0.02), but not vWf, whether with the adjustment of covariates or not. As for those < 60 years, between lone AF and age-matched controls, significant difference existed in the levels of sP-sel (AF vs. control: 34.5 ± 7.3 vs. 30.2 ± 7.3 ng/mL, P = 0.002), but not in those of fibrinogen and vWf, whether with the adjustment of covariates or not. CONCLUSIONS: Both platelet activation and abnormal changes in coagulation were suggested in idiopathic AF and a platelet activation state in lone AF. This supports the notion that AF per se contributes to a state of hypercoagulation.

[Changes of endothelial function indices and their relation to platelet activation in idiopathic atrial fibrillation].

OBJECTIVE: To investigate the changes of endothelial function indices and their relation to platelet activation in patients with idiopathic atrial fibrillation (AF). METHODS: We studied 61 patients with idiopathic AF with 34 age- and sex-matched healthy persons as control. Platelet counts in the blood were tested, and plasma levels of NOx were analyzed using Griess method. The plasma levels of von Willibrand factor (vWF) and soluble P-selectin (sP-selectin) were determined using enzyme-linked immunosorbent assay. RESULTS: Compared to healthy control, the patients with idiopathic AF had significantly lower levels of plasma NOx (18.2-/+7.3 vs 24.3-/+7.8 micromol/L, P=0.049) and higher levels of plasma sP-selectin (25.6-/+6.2 vs 22.4-/+4.8 ng/ml, P=0.007). No significant differences were found in the platelet counts or plasma vWF levels between the two groups. A significant inverse correlation was found between plasma NOx and sP-selectin (r=-0.405, P=0.025) in patients with idiopathic AF. CONCLUSION: AF per se may impair the endothelial function and activate platelet function, suggesting the role of endothelial dysfunction in activated platelet function in AF patients.

[Effects of oxygen and calcium on the expression of wild-type and mutated hypoxia-inducible factor-1alpha eukaryotic vectors in HEK293 cells].

OBJECTIVE: To study the effects of oxygen and calcium on the expression of eukaryotic vectors harboring wild-type or mutated hypoxia-inducible factor-1alpha (HIF-11alpha) in HEK293 cells. METHODS: HEK293 cells were transiently transfected with pcDNA3.1+/HIF-11alpha, pcDNA3.1+/HIF-11alpha-564Ala and pcDNA3.1+/HIF-11alpha-564Ala-803Ala via lipofectin. Western blotting were used to detect HIF-11alpha protein after normoxic or hypoxic exposure of the transfected HEK293 cells in the presence or absence of Ca(2+). The levels of vascular endothelial growth factor (VEGF) mRNA in the transfected cells in normoxic condition was detected using RT-PCR. RESULTS: The levels of HIF-11alpha protein and VEGF mRNA increased in HEK293 cells transfected with the vectors harboring mutated HIF-11alpha, but not in the cells transfected with wild-type HIF-11alpha vectors in normoxia. Hypoxia increased the levels of HIF-11alpha protein in the cells transfected with wild-type HIF-11alpha vectors, which was inhibited by the application of Ca(2+). Ca(2+) showed no inhibitory effect on HIF-11alpha levels in HEK293 cells transfected with the vectors containing mutated HIF-11alpha. CONCLUSION: The protein products of pcDNA3.1+/HIF-11alpha-564Ala and pcDNA3.1+/HIF-11alpha- 564Ala-803Ala in HEK293 cells enhance the cell tolerance to oxygen and protease.

[Effect of porcine relaxin on NO production of human microvascular endothelial cells].

OBJECTIVE: To observe effect of porcine relaxin(pRLX) on NO production of human microvascular endothelial cells(HMVECs) and discuss its possible mechanism. METHODS: iNOS and cNOS expression of HMVECs with or without pRLX were detected using western blotting. NO production of HMVECs with pRLX at different concentration or different time were determined by method of Griess. NO production of pRLX of HMVECs plus Non-selective NOS inhibitor NG-monomethyl-L-arginine(L-NMMA), selective iNOS inhibitor aminoguanidine(AG) or nuclear factors-kappaB (NF-kappaB) inhibitor pyrrolidine dithiocarbamate(PDTC) were also analysed. RESULTS: pRLX promoted iNOS protein expression of HMVECs, but not cNOS protein expression. NO production of HMVECs was promoted by pRLX on concentration-dependent pattern instead of time-dependent one. AG, L-NMMA and PDTC were showed to block the effect of pRLX on NO production of HMVECs. CONCLUSION: pRLX promote iNOS expression and NO production of HMVECs.

[Construction of eukaryotic expression vectors of two mutants of hypoxia-inducible factor-1 and their expressions in human microvascular endothelial cells].

OBJECTIVE: To construct eukaryotic expression vectors of two mutants of hypoxia-inducible factor-1 (HIF-1alpha) and study their expressions in human microvascular endothelial cells (HMVECs). METHODS: Site-directed mutagenesis was performed to induce the mutation of the codons for the residue Pro564 (ccc) in HIF-1alpha into gcc (Ala) in pcDNA3.1(+)-HIF-1alphato obtain single-site-mutated vector pcDNA3.1(+)-HIF-1alpha-564Ala, which was then subjected to a second site-directed mutagenesis to convert the codons for Asn803 into that of Ala (gct) to acquire double-site-mutated pcDNA3.1(+)-HIF-1alpha-564Ala-803Ala. After lipofectin-mediated transient transformation of HMVECs with the 3 recombinant plasmids including the two plasmids containing the mutations and the one without mutation, respectively, the expression levels of HIF-1alpha mRNA and protein were determined using RT-PCR, immunofluorescent staining and Western blotting. RESULTS: DNA sequence analysis demonstrated success of the two-step mutagenesis and the two plasmids of pcDNA3.1+-HIF-1alpha-564Ala and pcDNA3.1(+)-HIF-1alpha-564Ala- 803Ala were obtained, both of which could produce HIF-1alpha protein resistant to oxidation degradation in HMVECs as compared with the non-mutated one. CONCLUSION: The recombinant plasmids pcDNA3.1(+)-HIF-1alpha-564Ala and pcDNA3.1(+)-HIF-1alpha- 564Ala-803Ala have been successfully constructed with efficient expressions in HMVECs.

[Construction and expression analysis of recombinant vector pcDNA3.1+-HIF-1alpha].

OBJECTIVE: To construct the eukaryotic expression vector for human hypoxia-inducible factor-1alpha (HIF-1alpha) gene and examine its expression. METHODS: Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed on the total RNA extracted from HT29 cells to obtain the cDNA of HIF-1alpha, which was inserted into T vector pUC18. DNA sequencing was performed before the amplified products were cloned into the eukaryotic expression vector pcDNA3.1+ identified by endonuclease digestion. This recombinant vector was transfected into HEK293 cells by means of liposome and its expression examined. RESULTS: The amplified products were confirmed as the cDNA of HIF-1alpha by DNA sequencing, and pcDNA3.1+ -HIF-1alpha obtained was verified by endonuclease digestion, being capable of expression in HEK293 cells. CONCLUSION: We have successfully constructed the eukaryotic expression vector for HIF-1alpha, which can be expressed in HEK293 cells.

Dynamic changes in type I collagen, MMP-1 and TIMP-1 after angioplasty.

OBJECTIVE: To investigate the dynamic changes of type I collagen, and the activity of metalloproteinases-1 (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) after angioplasty. METHODS: The restenotic model of iliac arteries of domestic microswine was established with hypercholesterol feed plus two angioplasties. Angioplastied vessels were harvested at the end of 1, 2, 3 and 6 months after the second angioplasty. Immunohistochemistry, transmission electronic microscopy and image quantitative analysis techniques were employed to study neointimal proliferation, the phenotype of vascular smooth muscle cells (VSMC) and the expression of type I collagen, MMP-1 and TIMP-1. RESULTS: The peak of vascular neointimal proliferation was at 3 months after angioplasty. The expression of type I collagen gradually increased from 1 to 6 months after angioplasty. For MMP-1, expression was lower in the early stage after angioplasty but increase to normal levels of control vessels at 6 months after angioplasty. Expression of TIMP-1 rapidly increased in the early phase after angioplasty, reached peak at 3 months and maintained the high level till 6 months after angioplasty. Meanwhile, the VSMC was predominantly the synthetic phenotype at the early stage and was transformed to the contractive phenotype at the late stage after angioplasty. The ratio of TIMP-1 and MMP-1 was positively related to the area of the neointima and the expression of type I collagen respectively (P < 0.01). CONCLUSION: Type I collagen increased gradually after angioplasty, which might be determined by the ratio of TIMP-1/MMP-1 and also related to the phenotype of VSMC.