[Association study between the KCNE family gene polymorphisms of potassium channel gene and the susceptibility of atrial fibrillation].

Objective: To investigate the relationship between KCNE family gene polymorphisms of potassium channel gene and the susceptibility of atrial fibrillation (AF). Methods: In the case-control study, a total of 648 subjects were studied, of which 338 patients with atrial fibrillation were selected from the Department of Cardiovascular Medicine, Putuo Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from January 2019 to December 2019, and 310 healthy people were selected from the physical examination population during the same period. DNA sequencing technology and polymerase chain reaction (PCR) were used to detect the genotype and allele frequency of rs1805127 of KCNE1, rs9984281 of KCNE2, rs9516, rs626930 of KCNE3 and rs12621643 of KCNE4. Results: The ages of subjects in atrial fibrillation group and control group were (69±13) and (73±8) years, respectively (P=0.077). Men subjects accounted for 57.70% (195 men) and 40.00% (124 men) in the two groups, respectively (P=0.092). The distribution frequencies of the allele C at rs1805127 of gene KCNE1, the allele A at rs9984281 of gene KCNE2 and the allele G at rs12621643 of gene KCNE4 were significantly different between groups (P<0.05). After adjustment for sex, smoking, hypertension, cardiac insufficiency and other factors, it was found that the increase in the frequency of the above three loci would increase the risk of atrial fibrillation (rs1805127 OR=7.064, 95%CI:1.559-31.997; rs9984281 OR=4.210, 95%CI:1.118-15.850; rs12621643 OR=2.679, 95%CI:1.025-6.998). Conclusion: The rs1805127 of KCNE1, the rs9984281 of KCNE2,the rs12621643 of KCNE4 were significantly associated with the susceptibility to atrial fibrillation.

Real-time optical manipulation of cardiac conduction in intact hearts.

KEY POINTS: Although optogenetics has clearly demonstrated the feasibility of cardiac manipulation, current optical stimulation strategies lack the capability to react acutely to ongoing cardiac wave dynamics. Here, we developed an all-optical platform to monitor and control electrical activity in real-time. The methodology was applied to restore normal electrical activity after atrioventricular block and to manipulate the intraventricular propagation of the electrical wavefront. The closed-loop approach was also applied to simulate a re-entrant circuit across the ventricle. The development of this innovative optical methodology provides the first proof-of-concept that a real-time all-optical stimulation can control cardiac rhythm in normal and abnormal conditions. ABSTRACT: Optogenetics has provided new insights in cardiovascular research, leading to new methods for cardiac pacing, resynchronization therapy and cardioversion. Although these interventions have clearly demonstrated the feasibility of cardiac manipulation, current optical stimulation strategies do not take into account cardiac wave dynamics in real time. Here, we developed an all-optical platform complemented by integrated, newly developed software to monitor and control electrical activity in intact mouse hearts. The system combined a wide-field mesoscope with a digital projector for optogenetic activation. Cardiac functionality could be manipulated either in free-run mode with submillisecond temporal resolution or in a closed-loop fashion: a tailored hardware and software platform allowed real-time intervention capable of reacting within 2 ms. The methodology was applied to restore normal electrical activity after atrioventricular block, by triggering the ventricle in response to optically mapped atrial activity with appropriate timing. Real-time intraventricular manipulation of the propagating electrical wavefront was also demonstrated, opening the prospect for real-time resynchronization therapy and cardiac defibrillation. Furthermore, the closed-loop approach was applied to simulate a re-entrant circuit across the ventricle demonstrating the capability of our system to manipulate heart conduction with high versatility even in arrhythmogenic conditions. The development of this innovative optical methodology provides the first proof-of-concept that a real-time optically based stimulation can control cardiac rhythm in normal and abnormal conditions, promising a new approach for the investigation of the (patho)physiology of the heart.

Effects of heat treatment of soy protein isolate on the growth performance and immune function of broiler chickens.

This study was conducted to evaluate the effects of oxidative modification of soy protein isolate (SPI) after exposure to heat on the growth performance and immune function of broilers. The SPI was heated in an oven at 100°C for 1, 4, and 8 h, respectively, and resultant oxidative status was evaluated. A total of 320 one-day-old Arbor Acres chickens were randomly divided into 4 treatment groups with 8 replicates of 10 birds, and fed diets supplemented with the native SPI or 1 of the 3 heat-treated SPI for 21 d. The results showed that heat exposure of SPI for 4 and 8 h caused an increase in protein carbonyl (P < 0.05), and a simultaneous decrease in sulfhydryl and free amine groups (P < 0.05) compared with native SPI. The BW of broilers fed diets supplemented with SPI heated for 8 h were significantly lower than that of broilers fed diets supplemented with native SPI (P < 0.05). Compared with native SPI, heat-treated SPI (heated for 8 h) diminished liver weight at 14 d (P = 0.01), spleen (P < 0.01) and bursa (P < 0.05) weights at 21 d; and the content of IgG in serum and duodenal mucosa of broilers (at 14 d) was decreased when diets supplemented with heat-treated SPI (heated for 8 h; P < 0.01). No significant differences were observed in the mucosa secretory IgA contents of broilers among the treatment groups (P > 0.05). Compared with native SPI, a significant increases were observed in the content of adrenocorticotropic hormone and cortisol in serum of broilers fed the heat-treated SPI (heated for 8 h) at 21 d (P < 0.05); and the myeloperoxidase activities in serum (at 14 d) and mucosa of broilers were increased when diets supplemented with heat-treated SPI (heated for 8 h; P < 0.05). The present study suggests that protein oxidation of SPI is induced by heating, and oxidized protein may negatively affect the immune function of broilers.

Cloning and expression analysis of phytoene desaturase and ζ-carotene desaturase genes in Carica papaya.

The fruit flesh color of papaya is an important nutritional quality trait and is due to the accumulation of carotenoid. To elucidate the carotenoid biosynthesis pathway in Carica papaya, the phytoene desaturase (PDS) and the ζ-carotene desaturase (ZDS) genes were isolated from papaya (named CpPDS and CpZDS) using the rapid amplification of cDNA ends (RACE) approach, and their expression levels were investigated in red- and yellow-fleshed papaya varieties. CpPDS contains a 1749 bp open reading frame coding for 583 amino acids, while CpZDS contains a 1716 bp open reading frame coding for 572 amino acids. The deduced CpPDS and CpZDS proteins contain a conserved dinucleotide-binding site at the N-terminus and a carotenoid-binding domain at the C-terminus. Papaya genome sequence analysis revealed that CpPDS and CpZDS are single copy; the CpPDS was mapped to papaya chromosome LG6, and the CpZDS was mapped to chromosome LG3. Quantitative PCR showed that both CpPDS and CpZDS were expressed in all tissues examined with the highest expression in maturing fruits, and that the expression of CpPDS and CpZDS were higher in red-fleshed fruits than in yellow-fleshed fruits. These results indicated that the differential accumulation of carotenoids in red- and yellow-fleshed papaya varieties might be partly explained by the transcriptional level of CpPDS and CpZDS.