Fate of carotenoids in yeasts: synthesis and cleavage.

Carotenoids and their cleavage products (norisoprenoids) have excellent functional properties with diverse applications in foods, medicaments, cosmetics, etc. Carotenoids can be oxidatively cleaved through nonspecific reactions or by carotenoid cleavage oxygenases (CCOs), the product of which could further modify food flavor. This review provides comprehensive information on both carotenoid synthesis and cleavage processes with emphasis on enzyme characterization and biosynthetic pathway optimization. The use of interdisciplinary approaches of bioengineering and computer-aided experimental technology for key enzyme modification and systematic pathway design is beneficial to monitor metabolic pathways and assess pathway bottlenecks, which could efficiently lead to accumulation of carotenoids in microorganisms. The identification of CCOs spatial structures isolated from different species has made a significant contribution to the current state of knowledge. Current trends in carotenoid-related flavor modification are also discussed. In particular, we propose the carotenoid-synthesizing yeast Rhodotorula spp. for the production of food bioactive compounds. Understanding the behavior underlying the formation of norisoprenoids from carotenoids using interdisciplinary approaches may point toward other areas of investigation that could lead to better exploiting the potential use of autochthonous yeast in flavor enhancement.

Association between season of conception, month of conception with preterm birth in China: a population-based retrospective cohort study.

BACKGROUND: Seasonal patterns of preterm birth were identified in previous studies, but the effect of conception season on preterm birth has not been extensively studied. Based on the notion that the etiological roots of preterm birth lie in the beginning of pregnancy, we did a population-based retrospective cohort study in Southwest China to examine the effects of season of conception and month of conception on preterm birth. METHODS: We did a population-based retrospective cohort study in women (aged 18-49) who participated in the NFPHEP from 2010 to 2018, and had a singleton livebirth in southwest China. According to the time of the last menstruation reported by the participants, month of conception and season of conception were then ascertained. We used multivariate log-binomial model to adjust the potential risk factors for preterm birth and obtained adjusted risk ratio (aRR) and 95% confidence intervals (95%CI) for conception season, conception month and preterm birth. RESULTS: Among 194 028 participants, 15 034 women had preterm birth. Compared with pregnancies that were conceived in the summer, pregnancies that were conceived in the spring, autumn and winter had the higher risk of preterm birth (Spring: aRR = 1.10, 95% CI: 1.04-1.15; Autumn: aRR = 1.14, 95% CI: 1.09-1.20; Winter: aRR = 1.28, 95% CI: 1.22-1.34) and also had a higher risk of early preterm birth (Spring: aRR = 1.09, 95% CI: 1.01-1.18; Autumn: aRR = 1.09, 95% CI: 1.01-1.19; Winter: aRR = 1.16, 95% CI: 1.08-1.25). Pregnancies in December, and January had a higher risk of preterm birth and early preterm birth than pregnancies that were conceived in July. CONCLUSIONS: Our study found that preterm birth was significantly related to season of conception. Preterm and early preterm birth rates were the highest among pregnancies that were conceived in winter, and the lowest among pregnancies in summer.

[circ_0092315 Promotes Proliferation and Invasion of Papillary Thyroid Carcinoma Cells via Regulating microRNA-1256/High Mobility Group A2 axis].

Objective To investigate the role and mechanism of circ_0092315 in the proliferation and invasion of papillary thyroid carcinoma cells. Methods The expression of circ_0092315 in papillary thyroid carcinoma cells was examined by real-time fluorescence quantitative PCR.The proliferation and invasion of TPC-1 cells was assessed by CCK-8 and Transwell assays.The protein level of high mobility group A2 (HMGA2) was determined by Western blotting.The regulatory relationship of circ_0092315,microRNA-1256 (miR-1256),and HMGA2 was explored by bioinformatics tools,dual-luciferase reporter assay,real-time fluorescence quantitative PCR,and Western blotting. ++++Results circ_0092315 was overexpressed in papillary thyroid carcinoma cells (all P<0.001).circ_0092315 promoted the proliferation and invasion of TPC-1 cells (all P<0.001).The transfection of si-circ_0092315 up-regulated the expression of miR-1256 (P<0.001),and miR-1256 inhibitor up-regulated the protein level of HMGA2 (P<0.001). ++++Conclusion circ_0092315 is overexpressed in TPC-1 cells and it promotes the proliferation and invasion of TPC-1 cells by regulating the miR-1256/HMGA2 axis.

The association between periconceptional folic acid supplementation and the risk of preterm birth: a population-based retrospective cohort study of 200,000 women in China.

PURPOSE: The aim of this study was to examine the association between periconceptional folic acid (FA) supplementation and risk of preterm birth. METHODS: We conducted a retrospective cohort study in women aged 18-49 who participated in the NFPHEP from 2010 to 2018, and had a singleton livebirth in 129 counties in southwest China. Participants were divided into four groups according to the time period starting FA use: no use, after the last menstrual period, at least 1-2 months before the last menstrual period, at least 3 months before the last menstrual period. The outcomes were preterm birth (gestation < 37 weeks) and early preterm birth (gestation < 34 weeks). RESULTS: 201,477 women were included and 191,809 (95.2%) had taken FA during periconception. Compared with women who did not take FA, women who started taking FA 1-2 months before their last menstrual period had a 15% lower risk of preterm birth (aOR = 0.85, 95% CI 0.79-0.92), and women who started taking FA at least 3 months before their last menstrual period had a 20% lower risk of preterm birth (aOR = 0.80, 95% CI 0.75-0.87), but women who started taking FA after their last menstrual period did not appear to reduce the risk of preterm birth. CONCLUSIONS: In this study of 200,000 Chinese women, periconceptional supplementation with FA was associated with a lower risk of preterm birth. Women who started taking FA at least 3 months before their last menstrual period were more likely to reduce the risk of preterm birth.

Prevalence of anemia and sociodemographic characteristics among pregnant and non-pregnant women in southwest China: a longitudinal observational study.

BACKGROUND: Globally, the prevalence of anemia among women of reproductive age is about 29.4%, and anemia impacts about 40% of pregnant women and more than 20% of non-pregnant women. We conducted a longitudinal observational study of anemia in pregnant and non-pregnant women, and analyzed the association between the prevalence of anemia and sociodemographic characteristics of women in southwest China. METHODS: This study was a longitudinal observational study which involved 640,672 women aged 18-49 years from 129 counties in southwest China. Data were from databases of National Free Preconception Health Examination Project (NFPHEP) and electronic medical records of local hospitals. We adjusted the diagnostic thresholds of anemia for altitude. The prevalence of anemia was expressed in percentages and 95% confidence intervals (95% CI). The association between the prevalence of anemia and sociodemographic characteristics of pregnant and non-pregnant women were analyzed using univariate and multivariate logistic regression method, expressed in crude odds ratio (cOR), adjusted odds ratio (aOR) and 95%CI. RESULTS: Of the 640,672 participants, 121,254 women suffered from anemia, with the prevalence of 18.9% (95%CI: 18.8-19.0%). From 2014 to 2018, the prevalence of anemia declines from 23.0-16.4%.The prevalence was 21.6% in the first trimester, higher than women in non-pregnancy (17.4%) and women in the third trimester (10.5%). Results from the multivariable logistic regression showed that women aged 18-20 (aOR = 1.28) or over 35 years old (aOR = 1.07), being farmers (aOR = 1.42), being ethnic minorities (aOR: 1.19 ~ 1.73), during the first trimester (aOR = 1.32) were more likely to be anemic. CONCLUSIONS: Although the anemia prevalence of women of reproductive age has been decreasing in recent years, the prevalence of anemia is still high in pregnant and non-pregnant women in southwest China, especially during the first trimester. Women who were older or younger, being farmers, being ethnic minorities were at high risk of anemia. Anemia in women of reproductive age cannot be neglected.

Effects of ambient temperature and relative humidity on preterm birth during early pregnancy and before parturition in China from 2010 to 2018: a population-based large-sample cohort study.

Background: The progression of global warming and increase in instances of extreme weather have received considerable attention. We conducted a cohort study on women of childbearing age in Yunnan Province, examined the association between ambient temperature and humidity on preterm birth and evaluated the effects of extreme weather during early pregnancy and before parturition on preterm birth. Methods: We conducted a population-based cohort study on women of childbearing age 18-49 years who participated in National Free Preconception Health Examination Project (NFPHEP) in Yunnan Province from January 1, 2010, to December 31, 2018. Meteorological data, namely daily average temperature (°C) and daily average relative humidity (%), were obtained from China National Meteorological Information Center. Four exposure windows were explored: 1 week of pregnancy, 4 weeks of pregnancy, 4 weeks before delivery, and 1 week before delivery. We used a Cox proportional hazards model and adjusted the potential risk factors for preterm birth to obtain the effects of exposure to temperature and humidity on preterm birth among the stages of pregnancy. Results: At 1 week of pregnancy and at 4 weeks of pregnancy, the association between temperature and preterm birth was U-shaped. The correlation between relative humidity and the risk of preterm birth was n-type at 1 week of pregnancy. The correlation between preterm birth and temperature and relative humidity at 4 weeks before delivery and at 1 week before delivery is J-shaped. Low temperature and low humidity were protective factors against preterm birth, whereas high temperature and high humidity were risk factors for preterm birth.The effects of high temperature and extremely high temperature were the strongest at 4 weeks before delivery, with HRs of 1.417 (95% CI: 1.362-1.474) and 1.627 (95% CI: 1.537-1.722), respectively. The effects of extremely low humidity and low humidity were strongest at 1 week before delivery, with HRs of 0.681 (95% CI: 0.609-0.761) and 0.696 (95% CI: 0.627-0.771), respectively. Conclusion: Temperature and relative humidity affect preterm birth differently for each pregnancy stage. The effects of meteorological factors on pregnancy outcomes such as premature birth should not be ignored.

Ethnic differences in preterm birth in Southwest China, 2014-2018: A population-based observational study.

Objective: Preterm birth is a major healthcare problem and has been rising gradually in the past three decades in China. Yet the ethnic differences in the rates and distributions of preterm birth remain largely unknown in China. This study used data from Yunnan, a multiethnic province, to explore the differences in preterm birth across ethnicities. Methods: A population-based observational study was conducted based on data from the National Free Preconception Health Examination Project in rural Yunnan from Jan 1, 2014 to Dec 31, 2018. Pregnancies with at least one livebirth were included in this study. We estimated the rates and 95% confidence intervals (CIs) of overall preterm birth (born < 37 weeks' gestation), moderate to late preterm birth (born between 32 and <37 weeks' gestation), very preterm birth (born between 28 and 31 weeks' gestation), and extremely preterm birth (born < 28 weeks' gestation) across maternal ethnicity and compared them using log-binomial regressions. Multivariable log-binomial regressions were used to assess the association between maternal ethnicity and preterm birth with adjustment for potential confounders, including year of delivery, maternal age at delivery, education, occupation, pre-pregnancy body mass index, history of chronic disease, history of preterm birth, smoking and drinking alcohol during early pregnancy, and parity and multiple pregnancy of current pregnancy. Results: Among 195,325 women who delivered at least one live baby, 7.90% (95% CI, 7.78-8.02%) were born preterm. The rates of moderate to late preterm birth, very preterm birth, and extremely preterm birth were 6.20% (95% CI, 6.09-6.30%), 1.18% (95% CI, 1.13-1.23%), and 0.52% (95% CI, 0.49-0.56%), respectively. The rates of overall preterm birth, moderate to late preterm birth, very preterm birth, and extremely preterm birth differed across maternal ethnicity. The preterm birth rates in Dai (10.73%), Miao (13.23%), Lisu (12.64%), Zhuang (11.77%), Wa (10.52%), and Lagu (12.34%) women were significantly higher than that in Han women, and the adjusted relative risks were 1.45 [95% CI, 1.36, 1.54], 1.74 (95% CI, 1.62, 1.86), 1.60 (95% CI, 1.47, 1.75), 1.60 (95% CI, 1.46, 1.75), 1.40 (95% CI, 1.22, 1.60), and 1.67 (95% CI, 1.50, 1.87) respectively. There was no difference in preterm birth rate between Han women and Hani, Bai, or Hui women. Conclusion: This study found notable differences in the rates of preterm birth and its sub-categories across maternal ethnicities, which were especially higher in ethnic minority women. The findings suggest that greater efforts to reduce ethnic inequalities in preterm birth. Future studies are warranted to understand the drivers of ethnic inequalities in preterm birth in China.

Fine tuning of medium chain fatty acids levels increases fruity ester production during alcoholic fermentation.

Pichia fermentans Z9Y-3 and its intracellular enzymes were inoculated along with S. cerevisiae in synthetic grape must to modulate fruity ester production. The levels of ester-related enzymes, ester precursors, and fruity esters were monitored every 24 h during fermentation. Results showed that the levels of ethyl acetate, acetate higher alcohol esters (AHEs), short chain fatty acid ethyl esters (SFEs), and medium chain fatty acid ethyl esters (MFEs) were significantly enhanced in mixed fermentation. Pearson correlation analysis further revealed that higher alcohols and fatty acids played a more important role in fruity ester production than enzymes; Particularly, the correlation coefficient between fatty acids and MFEs was 0.940. In addition, supplementation of medium chain fatty acids (7.2 mg/L) at the metaphase of single S. cerevisiae fermentation improved ethyl acetate, AHE, SFE, and MFE production by 42.56%, 21.00%, 61.33%, and 90.04%, respectively, although the high level of ethyl acetate might result in off-flavors.

Ethnic Disparities in Hepatitis B Virus Infection Among 1 Million Reproductive-Age Couples Preparing for Pregnancy in the Rural Yunnan, China: A Population-Based Cross-Sectional Study.

INTRODUCTION: Hepatitis B is a potentially life-threatening liver infection caused by hepatitis B virus (HBV) and China has the largest disease burden. We aim to understand the ethnic disparities in HBV infection among the married reproductive-age couples planning for pregnancy in Yunnan, a multiethnic province in Southwest China, to increase the health equities within the hepatitis response in China. METHODS: A population-based cross-sectional study was performed. Couples aged 20-49 years in rural Yunnan were enrolled through the National Free Preconception Health Examination Project from Jan 2014 to Dec 2019. HBsAg-positive couples were defined as couples in which one or both were HBsAg-positive, and HBsAg- and HBeAg-positive couples were defined as couples in which one or both were HBsAg- and HBeAg-positive. The HBV prevalence of positive couples was estimated by ethnicity. Multivariate logistic regression analyses were used to assess the association between ethnicity and HBsAg status. RESULTS: Overall, 63,513 of 1,060,643 couples (5.99%, 95% CI, 5.94%-6.03%) were HBsAg-positive, and 15,898 of 63,513 HBsAg-positive couples (25.03%, 95% CI 24.69%-25.37%) were HBsAg- and HBeAg-positive couples in rural Yunnan. The highest prevalence of HBsAg-positive couples was in the Miao and Miao ethnicity (12.04%) and Zhuang and Zhuang ethnicity (9.76%), and the risk of HBV infection of wives/husbands in these ethnic groups was significantly higher than that in the Han and Han ethnicity. Additionally, the HBsAg prevalence in wives/husbands has increased with the positive status of HBsAg and HBeAg of their spouses. CONCLUSION: The HBV prevalence in reproductive-age couples was intermediate (6% of 1 million couples) in rural Yunnan, China, with the highest in the Miao and Zhuang ethnicities. There are still large ethnic disparities in HBV infection in China. Therefore, China should make great efforts, especially giving priority to ethnic minorities and taking positive couples as an important unit of care, to equitably eliminate the HBV intrafamilial transmission.

[Application of different surface treatment methods in teeth restoration with nano composite resin].

PURPOSE: To investigate the effects of different surface treatments and adhesive self-etch functional monomers on the immediate repair bond strength and integrity of the repaired resin composite interface. METHODS: Ninety-eight resin composite blocks made of a nanohybrid resin composite were randomly divided into seven groups, each with 14 blocks, including positive control group: non-conditioned surface, Group A1: Gluma Comfort Bond, Group A2: Gluma Comfort Bond and sandblasting, Group B1: Tokuyama Bond Force IITM adhesive system, Group B2: Tokuyama Bond Force IITM adhesive system and sandblasting, Group C: polishing, and Group D: sandblasting. Resin composite identical to the substrate was applied and the repaired specimens were subjected to shear bond strength (SBS) testing. Representative samples from all groups received scanning electron microscopy and surface profilometry to determine their mode of failure. The data were processed with SPSS 20.0 software package. RESULTS: SBS of Group D was significantly higher than that of positive control group (P<0.05). SBS of Group A1, A2, B1 and B2 was significantly higher than that of Group C and D (P<0.05). Comparison of SBS among Group B1, D and A1 showed no significant difference(P>0.05). SBS between Group B2 and positive control group had no significant difference(P>0.05). Except specimens with sandblasting and the use of TBF II system, SBS of positive control group was significantly higher than that of Group A1 and C(P<0.05). The polished specimens had significantly more adhesive failures than those with sandblasted surfaces (P<0.05). Specimens treated with polishing and Gluma Comfort Bond showed significantly more adhesive failures than those treated with polishing and TBF II system (P<0.05). The sandblasted surfaces conditioned with TBF II showed significantly more cohesive failures than those treated with polishing and TBF II (P<0.05). The sandblasted specimens provided significantly more irregular and rougher surface finish than the polishing technique (P<0.05). CONCLUSIONS: Sandblasting of the composite substrate and the use of TBF II adhesive system shows the highest repair bond strength, higher adhesive interfacial failures and fewer cohesive failures; however, it is noteworthy that the composite substrate types yield statistically higher food residue rate, which results in poor oral hygiene maintenance. Therefore, the application of this repair protocol should match up with correct oral health behaviors.

Chemical profiles and aroma contribution of terpene compounds in Meili (Vitis vinifera L.) grape and wine.

The chemical profiles and aroma contribution of terpene compounds in Meili grapes and wine were analyzed. Bound terpene compounds were extracted using methanol, purified using Amberlite XAD-2 resin, concentrated in methanol/ethyl acetate, and enzymatically hydrolyzed to release aglycones. Free terpene compounds were identified using solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Wine aroma characteristics were quantified by a trained sensory panel. Seventeen terpene glycosides were quantified in grapes and wines as pentosyl-glucopyranoside, the content of which ranged from 804 to 836 µg/kg, and from 155 to 192 µg/L, respectively. Eight free terpenes were present in wines with their content ranging from 40.1 to 59.7 µg/L. Linalool was abundant both in bound and free terpenes, and mathematical regression revealed that terpenes, especially linalool (contribution efficient > 0.4), contributed heavily to Meili wine aroma. Finally, a molecular rearrangement scheme based on linalool was proposed in Meili grape and wine.

Evolution of volatile compounds treated with selected non-Saccharomyces extracellular extract during Pinot noir winemaking in monsoon climate.

The dynamic pattern of volatiles during Pinot Noir winemaking in monsoon climate with yeast extracellular extract (EE) treatment was analyzed. EE from selected Pichia fermentans and Rhodotorula mucilaginosa strains, and almond ß-glucosidase were added after 12-h alcohol fermentation, and the volatiles were determined every 24 h by GC-MS. After 6-month storage, wine aroma was evaluated instrumentally as well as by well-trained panelists. Results showed that enzyme treatments improved the contents of both varietal and fermentative volatiles. The levels of C6 compounds, terpenes, and higher alcohols increased constantly during alcohol fermentation, whereas acetates, short and medium chain fatty acid ethyl esters, phenylethyls, and fatty acids increased first, followed by gradual decrease. EE treatment retarded the decrease of fruity ester content in wine. Mathematical regression between wine aroma and volatiles showed that the relatively higher contents of acetates, ethyl esters, and C13-norisoprenoids in 6-month EE-treated wine were responsible for the improvement in floral aroma intensity.

Biomarkers for Early Diagnostic of Mild Cognitive Impairment in Type-2 Diabetes Patients: A Multicentre, Retrospective, Nested Case-Control Study.

BACKGROUND: Both type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) are common age-associated disorders and T2DM patients show an increased risk to suffer from AD, however, there is currently no marker to identify who in T2DM populations will develop AD. Since glycogen synthase kinase-3ß (GSK-3ß) activity, ApoE genotypes and olfactory function are involved in both T2DM and AD pathogenesis, we investigate whether alterations of these factors can identify cognitive impairment in T2DM patients. METHODS: The cognitive ability was evaluated using Minimum Mental State Examination (MMSE) and Clinical Dementia Rating (CDR), and the mild cognitive impairment (MCI) was diagnosed by Petersen's criteria. GSK-3ß activity in platelet, ApoE genotypes in leucocytes and the olfactory function were detected by Western/dot blotting, the amplification refractory mutation system (ARMS) PCR and the Connecticut Chemosensory Clinical Research Center (CCCRC) test, respectively. The odds ratio (OR) and 95% confidence intervals (95% CI) of the biomarkers for MCI diagnosis were calculated by logistic regression. The diagnostic capability of the biomarkers was evaluated by receiver operating characteristics (ROC) analyses. FINDINGS: We recruited 694 T2DM patients from Jan. 2012 to May. 2015 in 5 hospitals (Wuhan), and 646 of them met the inclusion criteria and were included in this study. 345 patients in 2 hospitals were assigned to the training set, and 301 patients in another 3 hospitals assigned to the validation set. Patients in each set were randomly divided into two groups: T2DM without MCI (termed T2DM-nMCI) or with MCI (termed T2DM-MCI). There were no significant differences for sex, T2DM years, hypertension, hyperlipidemia, coronary disease, complications, insulin treatment, HbA1c, ApoE ε2, ApoE ε3, tGSK3ß and pS9GSK3ß between the two groups. Compared with the T2DM-nMCI group, T2DM-MCI group showed lower MMSE score with older age, ApoE ε4 allele, higher olfactory score and higher rGSK-3ß (ratio of total GSK-3ß to Ser9-phosphorylated GSK-3ß) in the training set and the validation set. The OR values of age, ApoE ε4 gene, olfactory score and rGSK-3ß were 1.09, 2.09, 1.51, 10.08 in the training set, and 1.06, 2.67, 1.47, 7.19 in the validation set, respectively. The diagnostic accuracy of age, ApoE ε4 gene, olfactory score and rGSK-3ß were 0.76, 0.72, 0.66, 0.79 in the training set, and 0.70, 0.68, 0.73, 0.79 in the validation set, respectively. These four combined biomarkers had the area under the curve (AUC) of 82% and 86%, diagnostic accuracy of 83% and 81% in the training set and the validation set, respectively. INTERPRETATION: Aging, activation of peripheral circulating GSK-3ß, expression of ApoE ε4 and increase of olfactory score are diagnostic for the mild cognitive impairment in T2DM patients, and combination of these biomarkers can improve the diagnostic accuracy.