Antenatal steroid as an independent risk factor for vitamin K2 deficiency in newborns: A Chinese single-center, retrospective study.

OBJECTIVES: To identified vitamin K2 deficiency rate and risk factors among newborns in China and assess the importance of high-risk maternal intakes of vitamin K2. METHODS: This retrospective study was performed at the Neonatology Department, the Affiliated Hospital of Guangdong Medical University, China. Routinely collected mother-neonate hospitalization data from July 2020 to January 2021 were analyzed. In total, data from 200 neonates who had completed vitamin K2 tests were utilized to assess the prevalence of vitamin K2 deficiency and identify the potential risk factors. According to the vitamin K2 level, the neonates were divided into 2 groups: cases (vitamin K2 deficiency) and controls (no vitamin K2 deficiency). The potential risk factors for vitamin K2 deficiency were evaluated by univariate and multivariate logistic regression. RESULTS: The vitamin K2 level in 24 of the 200 neonates was undetectable (<0.05 ng/mL). The prevalence of low serum vitamin K2 (<0.1 ng/ml) was 33%. Study subjects with antenatal corticosteroids use had an approximately 5-fold greater risk of developing vitamin K2 deficiency. In the univariate analyses, small-for-gestational-age (SGA), caesarean section, maternal gestational diabetes and premature rupture of the membranes were risk factors for vitamin K2 deficiency. In the multivariate logistic regression analysis, high antenatal corticosteroids use, cesarean section, and SGA were independently associated with vitamin K2 deficiency. CONCLUSION: The present study demonstrated that antenatal corticosteroids use is independently associated with vitamin K2 deficiency. This finding highlights the importance of routine vitamin K2 supplementation in late-stage pregnant women and neonates in China.

Nesteretal A, A Novel Class of Cage-Like Polyketide from Marine-Derived Actinomycete Nesterenkonia halobia.

An intriguing cage-like polyhemiketal, nesteretal A (1), was isolated from the coral-derived actinomycete Nesterenkonia halobia. Its structure was established by extensive spectroscopic and computational methods. Nesteretal A is a highly oxygenated compound featuring an unprecedented 5/5/5/5 tetracyclic scaffold. A possible biosynthetic pathway of 1 from naturally occurring diacetyl was proposed. Compound 1 showed a weak retinoid X receptor-α (RXRα) transcriptional activation effect.

Enabling the extended compact genetic algorithm for real-parameter optimization by using adaptive discretization.

An adaptive discretization method, called split-on-demand (SoD), enables estimation of distribution algorithms (EDAs) for discrete variables to solve continuous optimization problems. SoD randomly splits a continuous interval if the number of search points within the interval exceeds a threshold, which is decreased at every iteration. After the split operation, the nonempty intervals are assigned integer codes, and the search points are discretized accordingly. As an example of using SoD with EDAs, the integration of SoD and the extended compact genetic algorithm (ECGA) is presented and numerically examined. In this integration, we adopt a local search mechanism as an optional component of our back end optimization engine. As a result, the proposed framework can be considered as a memetic algorithm, and SoD can potentially be applied to other memetic algorithms. The numerical experiments consist of two parts: (1) a set of benchmark functions on which ECGA with SoD and ECGA with two well-known discretization methods: the fixed-height histogram (FHH) and the fixed-width histogram (FWH) are compared; (2) a real-world application, the economic dispatch problem, on which ECGA with SoD is compared to other methods. The experimental results indicate that SoD is a better discretization method to work with ECGA. Moreover, ECGA with SoD works quite well on the economic dispatch problem and delivers solutions better than the best known results obtained by other methods in existence.