Objective:To investigate the incidence rate and development trend of birth defects in offspring after assisted reproductive technology (ART) in Beijing from 2010 to 2019.Methods:The institutions that carry out ART in Beijing were retrospectively investigated. The follow-up outcomes and the incidence of birth defects in a total of 389 978 ART treatment cycles were collected from 8 ART institutions between January 1, 2010 to December 31, 2019.Results:There were 1 367 ART pregnancies with birth defects, and the overall incidence rate was 120.87/10 000. The most common anomalies were malformations of circulatory system. The annual increase in birth defects was slightly higher during the pregnancy loss cycles (108.36%) than during the delivery cycles (103.77%). There was no significant difference in the prevalence of birth defects between artificial insemination (123.15?) and in vitro fertilization technology (105.23? , P=0.097). Conclusion:In recent 10 years, the incidence rate of birth defects in offspring conceived by ART at 8 reproductive centers in Beijing showed an increasing trend. The implementation of the tertiary prevention strategy of birth defects should be further strengthened to reduce the number of newborns with birth defects.

Objective:To investigate the incidence rate and development trend of birth defects in offspring after assisted reproductive technology (ART) in Beijing from 2010 to 2019.Methods:The institutions that carry out ART in Beijing were retrospectively investigated. The follow-up outcomes and the incidence of birth defects in a total of 389 978 ART treatment cycles were collected from 8 ART institutions between January 1, 2010 to December 31, 2019.Results:There were 1 367 ART pregnancies with birth defects, and the overall incidence rate was 120.87/10 000. The most common anomalies were malformations of circulatory system. The annual increase in birth defects was slightly higher during the pregnancy loss cycles (108.36%) than during the delivery cycles (103.77%). There was no significant difference in the prevalence of birth defects between artificial insemination (123.15?) and in vitro fertilization technology (105.23? , P=0.097). Conclusion:In recent 10 years, the incidence rate of birth defects in offspring conceived by ART at 8 reproductive centers in Beijing showed an increasing trend. The implementation of the tertiary prevention strategy of birth defects should be further strengthened to reduce the number of newborns with birth defects.

AIMTo investigate the role and mechanism of endothelium-derived hyperpolarizing factor (EDHF) in shear stress induced vasorelaxation of rat mesenteric artery.

METHODSThe changes in vessel diameter in response to variable flow (0-300 microL.min(-1)) were continuously examined. The contribution of prostacyclin (PGI2), NO and EDHF to shear stress induced relaxation were analyzed by inhibitory effects of indomethacin, N(G)-nitro-L-arginine (L-NA) and KCl. The nature and hyperpolarizing mechanism of EDHF were examined by the inhibitory effects of inhibitors of cytochrome P450 pathway and of various K+ channels.

RESULTSThe shear stress-induced relaxation were endothelium dependent and the contribution of NO was more prominent in large mesenteric arteries (400-500 microm) than that in resistance arteries (150-250 microm), whereas that of EDHF was noted in both-sized blood vessels. Tetrabutylammonium (a nonselective inhibitor of K channels) almost abolished, whereas the combination of charybdotoxin (an inhibitor of both large and intermediate-conductance Ca2+-activated K channels) and apamin (an inhibitor of small-conductance Ca2+-activated K channels) significantly inhibited the EDHF-mediated component of the shear stress-induced relaxations.

CONCLUSIONEDHF plays an important role in shear stress-induced endothelium-dependent relaxations, and K channels especially calcium-activated K channels appear to be involved.

Animals ; Apamin ; pharmacology ; Biological Factors ; physiology ; Charybdotoxin ; pharmacology ; Cytochrome P-450 Enzyme Inhibitors ; Endothelium, Vascular ; drug effects ; physiology ; In Vitro Techniques ; Large-Conductance Calcium-Activated Potassium Channels ; antagonists & inhibitors ; Male ; Mesenteric Arteries ; drug effects ; physiology ; Nitric Oxide ; physiology ; Potassium Channel Blockers ; pharmacology ; Proadifen ; pharmacology ; Quaternary Ammonium Compounds ; pharmacology ; Rats ; Rats, Wistar ; Small-Conductance Calcium-Activated Potassium Channels ; antagonists & inhibitors ; Vasodilation ; drug effects