China is an urban and rural social model country. In the past three decades, the developing speed of rural areas has been much slower than urban areas, which may lead to the differences in dietary patterns. This study aimed to investigate the disparities of dietary structures from urban and rural children, and to analyze the effects of different dietary patterns on their adverse outcome. Among 1590 students, aged 11 years to 17 years, from primary and middle schools, a cross-sectional study was conducted. There were three dietary patterns recognized: Westernization structure, meat diet structure, and Western and Chinese structure. Compared with rural students, more urban students were in the highest categories of the whole dietary patterns (p < 0.001). Overweight/obesity and central adiposity were more prevailing among urban students, while rural students had a more prevailing risk of bone fracture (p < 0.05). Through the adjustment for all confounding factors, the Westernization structure could increase the risk of overweight/obesity and central adiposity, the meat structure could increase the risk of elevated blood pressure/hypertension, while the risk of low bone mineral quality could be reduced by the Chinese and Western structure. In conclusion, a rural-urban disparity in dietary patterns was found in our study, and different dietary patterns were associated with the risk of some adverse outcomes. Therefore, there were different prevalences of the adverse outcomes between rural and urban students.

Paclitaxel, a natural antitumor compound, is produced by yew trees at very low concentrations, causing a worldwide shortage of this important anticancer medicine. These plants also produce significant amounts of 7-␤-xylosyl-10-deacetyltaxol, which can be bio-converted into 10-deacetyltaxol for the semi-synthesis of paclitaxel. Some microorganisms can convert 7-␤-xylosyl-10-deacetyltaxol into 10-deacetyltaxol, but the bioconversion yield needs to be drastically improved for industrial applications. In addition, the related ␤-xylosidases of these organisms have not yet been defined. We set out to discover an efficient enzyme for 10-deacetyltaxol production. By combining the de novo sequencing of ␤-xylosidase isolated from Lentinula edodes with RT-PCR and the rapid amplification of cDNA ends, we cloned two cDNA variants, Lxyl-p1-1 and Lxyl-p1-2, which were previously unknown at the gene and protein levels. Both variants encode a specific bifunctional ␤-D-xylosidase/␤-D-glucosidase with an identical ORF length of 2412 bp (97% identity). The enzymes were characterized, and their 3.6-kb genomic DNAs (G-Lxyl-p1-1, G-Lxyl-p1-2), each harboring 18 introns, were also obtained. Putative substrate binding motifs, the catalytic nucleophile, the catalytic acid/base, and potential N-glycosylation sites of the enzymes were predicted. Kinetic analysis of both enzymes showed kcat/K m of up to 1.07 s ؊1 mM ؊1 against 7-␤-xylosyl-10-deacetyltaxol. Importantly, at substrate concentrations of up to 10 mg/ml (oversaturated), the engineered yeast could still robustly convert 7-␤-xylosyl-10-deacetyltaxol into 10-deacetyltaxol with a conversion rate of over 85% and a highest yield of 8.42 mg/ml within 24 h, which is much higher than those reported previously. Therefore, our discovery might lead to significant progress in the development of new 7-␤-xylosyl-10-deacetyltaxol-converting enzymes for more efficient use of 7-␤-xylosyltaxanes to semi-synthesize paclitaxel and its analogues. This work also might lead to further studies on how these enzymes act on 7-␤-xylosyltaxanes and contribute to the growing database of glycoside hydrolases. Molecular &

Several twin studies have investigated the overlap between attention deficit hyperactivity disorder (ADHD) and externalizing problems; however, limited information is known regarding the genetic and environmental contribution to the overlap between ADHD and internalizing problems. This study examined the genetic and environmental influences on the variation in and covariation between ADHD symptoms and internalizing problems by using the Child Behavior Checklist (CBCL). We investigated 1,316 child and adolescent twins, including 780 monozygotic twins and 536 dizygotic twins, aged 6 years to 18 years from the Chinese Child and Adolescent Twin Registry. ADHD symptoms and internalizing problems were quantified through parent rating by using the Attention Problems Scale and other three scales, which include Anxious/Depressed, Withdrawn, and Somatic Complaints of CBCL. Genetic and environmental susceptibilities common to ADHD symptoms and internalizing problems were examined through bivariate twin modeling. Results showed that genetic factors substantially influenced the ADHD symptoms with a heritability of 72%. Modest genetic influences and substantial shared environmental influences (20-77%) were observed in the three internalizing problem scales. Common genetic and shared environmental influences were essential for the overlap between ADHD and the three internalizing problems respectively. Approximately one-fifth of the genetic variance of ADHD symptoms was shared with anxiety/depression. In conclusion, substantial genetic and shared environmental influences on ADHD symptoms and internalizing problems were observed in Chinese children and adolescents. Our finding supports a common etiology between ADHD and internalizing problems. This finding can also help explain the coexistence of these behavior problems.

In contrast to most present-day high income countries, obesity among young people in China is associated with affluence and urban residence. Intervention and strategy for obesity prevention should be targeting high socioeconomic families in urban areas, perhaps with particular focus on boys.

A green and sustainable approach is established by metabolic engineering for industrial production of bioactive dammarenediol-II glucosides.

Evidence shows a secular trend in physical growth in China in recent years. We analyze the secular trend of stature and body mass index (BMI) for the period 1950s-2005 to provide biological evidence for policy-makers to identify measures for improving Chinese children's health. Data come from the historical records in 1950s and the successive cycles of the Chinese National Survey on Student's Constitution and Health. Subjects were 7- to 18-year-old youth from 16 cities. Sex-age differences in mean stature and BMI values between the surveys were analyzed, and the increments per decade were compared. An overall positive secular trend was found in 1950s-2005. Mean stature of the 18-year olds increased from 166.6 to 173.4 cm for males and from 155.8 to 161.2 cm for females, yielding rates of 1.3 and 1.1 cm/decade; the overall increments of BMI values were 2.6 for males and 1.8 for females, yielding rates of 0.8 and 0.6/decade, respectively. The most significant changes occurred during puberty. The overall positive secular trend is closely associated with the socioeconomic progress and the improvement of livelihood. Strong evidence suggests that in China this trend will be continued for many years. Further studies are needed to explore how to ensure healthy changes for poorer rural youth. Effective preventive strategies and measures should be taken to prevent the progressive increase in the prevalence of childhood obesity accompanying this trend.

The natural concentration of the anticancer drug Taxol is about 0.02% in yew trees, whereas that of its analogue 7-β-xylosyl-10-deacetyltaxol is up to 0.5%. While this compound is not an intermediate in Taxol biosynthetic route, it can be converted into Taxol by de-glycosylation and acetylation. Here, we improve the catalytic efficiency of 10-deacetylbaccatin III-10-O-acetyltransferase (DBAT) of Taxus towards 10-deacetyltaxol, a de-glycosylated derivative of 7-β-xylosyl-10-deacetyltaxol to generate Taxol using mutagenesis. We generate a three-dimensional structure of DBAT and identify its active site using alanine scanning and design a double DBAT mutant (DBATG38R/F301V) with a catalytic efficiency approximately six times higher than that of the wild-type. We combine this mutant with a β-xylosidase to obtain an in vitro one-pot conversion of 7-β-xylosyl-10-deacetyltaxol to Taxol yielding 0.64 mg ml−1 Taxol in 50 ml at 15 h. This approach represents a promising environmentally friendly alternative for Taxol production from an abundant analogue.

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