Correlation between lactate dehydrogenase and QTc interval prolongation in maintenance hemodialysis patients: a cross-sectional study.

BACKGROUND: Corrected QT (QTc) interval prolongation is one of the common causes of sudden cardiac death in patients with maintenance hemodialysis (MHD) patients. However, there are few studies on QTc prolongation in MHD patients. The concentration of lactate dehydrogenase (LDH) in hemodialysis population increased, and LDH was associated with the mortality of MHD patients. This study aimed to investigate the relationship between QTc interval prolongation and LDH in MHD patients. METHODS: This is a cross-sectional observational study. Patients who underwent MHD for more than 3 months in the Second Affiliated Hospital of Nantong University from November 2012 to November 2019 with complete data were selected as the research subjects. The patients were divided into the normal QTc interval group and the QTc interval prolongation group. The general data of patients and clinical laboratory indicators were collected retrospectively from the electronic medical record system. Pearson correlation analysis and binary logistic regression were used to analyze the correlation between LDH and QTc interval prolongation; the cut-off value of LDH predicting QTc interval prolongation was calculated by receiver operating characteristic (ROC) curve. RESULTS: The LDH level in the prolonged QTc interval group was significantly higher than that in the normal group (301.96±110.91 vs. 215.39±67.65, t=-8.03, P<0.001). QTc interval and LDH (r=0.386) were positively correlated. Binary logistic regression analysis showed that LDH, serum potassium <4 mmol/L, serum phosphorus, and left ventricular end-diastolic diameter (LVDd) were independent related factors for QTc interval prolongation. The ROC curve results showed that LDH =220 U/L was the best cutoff point for predicting QTc interval prolongation in MHD patients, with a sensitivity of 81.45% and a specificity of 59.35%. Binary logistic regression analysis showed that the LDH >220 U/L group was 6.34 times more likely to have QTc interval prolongation than the LDH ≤220 U/L group (OR 6.34, 95% CI: 3.47-11.58, P<0.001). CONCLUSIONS: LDH in MHD patients is closely related to QTc interval prolongation. Serum LDH, ionic calcium, serum phosphorus and potassium may predict QTc interval prolongation. Monitoring related indicators can remind clinicians to intervene as soon as possible to reduce the potential risk of arrhythmia and sudden cardiac death (SCD).

Simultaneous removal of nutrient and sulfonamides from marine aquaculture wastewater by concentrated and attached cultivation of Chlorella vulgaris in an algal biofilm membrane photobioreactor (BF-MPBR).

Microalgae based wastewater treatment has attracted increasing attention for its many advantages in recent years. In this study, a novel microalgae biofilm membrane photobioreactor (BF-MPBR) was developed for the efficient microalgae cultivation and the removal of nutrient and sulfonamides (SAs) from marine aquaculture wastewater. Two BF-MPBRs with hydraulic retention time (HRT) of 1 day and 2 days respectively were continuously operated for 70 days without harvesting microalgae. Concentrated and attached culture of marine Chlorella vulgaris was achieved in these continuous flow BF-MPBRs due to the suspended solid carriers and microfiltration membrane module in the reactors. The algal biomass productivity achieved in BF-MPBRs with HRT of 1 day and 2 days were 14.02 and 22.03 mg L-1 day-1, respectively. In addition, at the end of the cultivation, 60.4% and 45.0% of microalgae were fixed into algal biofilm in BF-MPBRs with 1 day and 2 day HRT, respectively. Compared with batch cultivation, more efficient nutrient and SAs removal performance was achieved in BF-MPBRs, although the HRT of the BF-MPBRs used in this study was only 1 or 2 days. During the stable operation stage of the BF-MPBRs, the reduction in dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), sulfadiazine (SDZ), sulfamethazine (SMZ) and sulfamethoxazole (SMX) were found in the range of 91.0-99.6%, 92.1-98.4%, 61.0-79.2%, 50.0-76.7% and 60.8-82.1%, respectively. Therefore, nutrient and SAs were simultaneously and efficiently removed from marine aquaculture wastewater by microalgae cultivation in BF-MPBR.

[Study on inhibitory effect of water extract of Polygonum multiflorum on CYP1A2 and CYP2E1 enzymatic activities and mRNA expressions in rat liver].

Rats were continuously given different doses of water extract of Polygonum multiflorum (1, 10 g x kg(-1)) for 7 days to prepare liver microsomes. Cocktail in vitro incubation approach and Real-time quantitative PCR technology were used to observe the effect of water extract of P. multiflorum on CYP450 enzymatic activities and mRNA expressions in rat liver. Compared with the blank control group, both 1, 10 g x kg(-1) water extract of P. multiflorum treated groups showed significant inhibitions in CYP2E1 enzymatic activities and mRNA expressions (enzymatic activities of CYP2E1, P < 0.01; mRNA expression of CYP2E1, P < 0.05 in 1 g x kg(-1) group, P < 0.01 in 10 g x kg(-1) group). They revealed a significant increase in the enzymatic activity of CYP3A1 (P < 0.01), but without significant change in mRNA expressions. The 10 g x kg(-1) group showed a significant inhibition in CYP1A2 enzymatic activities and mRNA expressions in rat livers (P < 0.01).

The BnGRF2 gene (GRF2-like gene from Brassica napus) enhances seed oil production through regulating cell number and plant photosynthesis.

Seed yield and oil content are two important agricultural characteristics in oil crop breeding, and a lot of functional gene research is being concentrated on increasing these factors. In this study, by differential gene expression analyses between rapeseed lines (zy036 and 51070) which exhibit different levels of seed oil production, BnGRF2 (Brassica napus growth-regulating factor 2-like gene) was identified in the high oil-producing line zy036. To elucidate the possible roles of BnGRF2 in seed oil production, the cDNA sequences of the rapeseed GRF2 gene were isolated. The Blastn result showed that rapeseed contained BnGRF2a/2b which were located in the A genome (A1 and A3) and C genome (C1 and C6), respectively, and the dominantly expressed gene BnGRF2a was chosen for transgenic research. Analysis of 35S-BnGRF2a transgenic Arabidopsis showed that overexpressed BnGRF2a resulted in an increase in seed oil production of >50%. Moreover, BnGRF2a also induced a >20% enlargement in extended leaves and >40% improvement in photosynthetic efficiency because of an increase in the chlorophyll content. Furthermore, transcriptome analyses indicated that some genes associated with cell proliferation, photosynthesis, and oil synthesis were up-regulated, which revealed that cell number and plant photosynthesis contributed to the increased seed weight and oil content. Because of less efficient self-fertilization induced by the longer pistil in the 35S-BnGRF2a transgenic line, Napin-BnGRF2a transgenic lines were further used to identify the function of BnGRF2, and the results showed that seed oil production also could increase >40% compared with the wild-type control. The results suggest that improvement to economically important characteristics in oil crops may be achieved by manipulation of the GRF2 expression level.