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1.
Ethanol fermentation from Jerusalem artichoke tubers was performed at elevated temperatures by the consolidated bioprocessing strategy using Saccharomyces cerevisiae MK01 expressing inulinase through cell surface display. No significant difference was observed in yeast growth when temperature was controlled at 38 and 40 °C, respectively, but inulinase activity with yeast cells was substantially enhanced at 40 °C. As a result, enzymatic hydrolysis of inulin was facilitated and ethanol production was improved with 89.3 g/L ethanol produced within 72 h from 198.2 g/L total inulin sugars consumed. Similar results were also observed in ethanol production from Jerusalem artichoke tubers with 85.2 g/L ethanol produced within 72 h from 185.7 g/L total sugars consumed. On the other hand, capital investment on cooling facilities and energy consumption for running the facilities would be saved, since regular cooling water instead of chill water could be used to cool down the fermentation system.  相似文献   
2.
Kernel size and kernel weight are important factors possibly involved in the determination of grain yield in maize, so identifying the genetic basis of kernel-related traits provides insights into the breeding of high-yield maize varieties. Kernel length (KL), kernel width (KW) and hundred kernel weight (HKW) were evaluated in three various planting conditions for the 240 field-grown double haploid (DH) lines derived from the single-cross hybrid Xianyu335. Variations in KL, KW and HKW were observed among DH lines, and all three traits showed a broad sense heritability of 76%. A total of 964 single nucleotide polymorphisms (SNPs) from the MaizeSNP3072 chip was utilised to create a high-density genetic map of 1546.4 cM and to identify quantitative trait loci (QTLs). Using composite interval mapping, a total of five, seven and five QTLs have been mapped for KL, KW and HKW, respectively. qkl1-2 and qkl4-1 explained 17.8% and 14.2% of the phenotypic variation in KL, respectively, and the other three QTLs contributed 3.2–4.0%. The phenotypic variation explained (PVE) of seven QTLs responsible for KW ranged from 3.3 to 9.5%. Three QTLs for HKW, qhkw1, qhkw5 and qhkw10 each explained more than 10% of the phenotypic variation, and qhkw4 and qhkw9 accounted for 3.0% and 6.0%, respectively. Due to their detection in multiple planting environments, the loci mapped here appear to be potential targets for the improvement of maize grain yield.  相似文献   
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Higher cognitive performance, maintenance of mental health and psychological well-being require adequate prefrontal cortex (PFC) function. “Inverted U-shaped” dopamine model indicates optimal PFC dopamine level is important to attain its function while high or low levels have adverse effects. Catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) may be involved in this complex non-linear PFC dopamine regulation. We addressed whether genetic variation reflecting COMT and MTHFR activities can explain the inter-individual mental health differences in healthy Japanese men (n = 188). The mental health was measured by Mental Health Inventory (MHI)-5 score. The rs4633–rs4818–rs4680 haplotypes were used to represent the multilevel COMT activities, while for MTHFR, the functional single polymorphism, rs1801133 (C677T), was used. We examined the effectiveness of haplotype-based association analysis of COMT on mental health together with studying its interaction with MTHFR-C677T. As a result, the relation between activity-ranked COMT genotype and MHI-5 score showed a tendency to fit into an “inverted U-shaped” quadratic curve (P = 0.054). This curvilinear correlation was significant in the subjects with MTHFR-CC (P < 0.001), but not with MTHFR T-allele carriers (P = 0.793). Our pilot study implies a potential influence of COMT and MTHFR genotypic combination on normal variation of mental health.  相似文献   
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Cholesterosis is a disease of cholesterol metabolism characterized by the presence of excessive lipid droplets in the cytoplasm. These lipid droplets are mainly composed of cholesterol esters derived from free cholesterol. The removal of excess cholesterol from gallbladder epithelial cells (GBECs) is very important for the maintenance of intracellular cholesterol homeostasis and the preservation of gallbladder function. Several lines of evidence have indicated that the activation of either peroxisome proliferator-activated receptor gamma (PPARγ) or liver X receptor α (LXRα) relates to cholesterol efflux. While pioglitazone can regulate the activation of PPARγ, 22(R)-hydroxycholesterol can activate LXRα and is a metabolic intermediate in the biosynthesis of steroid hormones. However, the effect of 22(R)-hydroxycholesterol in combination with pioglitazone on cholesterosis of the gallbladder is unclear. GBECs were treated with pioglitazone, 22(R)-hydroxycholesterol or PPARγ siRNA followed by Western blot analysis for ATP-binding cassette transporter A1 (ABCA1), PPARγ and LXRα. Cholesterol efflux to apoA-I was determined, and Oil Red O staining was performed to monitor variations in lipid levels in treated GBECs. Our data showed that 22(R)-hydroxycholesterol can modestly up-regulate LXRα while simultaneously increasing ABCA1 by 56%. The combination of 22(R)-hydroxycholesterol and pioglitazone resulted in a 3.64-fold increase in ABCA1 expression and a high rate of cholesterol efflux. Oil Red O staining showed an obvious reduction in the lipid droplets associated with cholesterosis in GBECs. In conclusion, the present findings indicate that the anti-lipid deposition action of 22(R)-hydroxycholesterol combined with pioglitazone involves the activation of the PPARγ–LXRα–ABCA1 pathway, increased ABCA1 expression and the efflux of cholesterol from GBECs. Thus, 22(R)-hydroxycholesterol synergistically combined with pioglitazone to produce a remarkable effect on lipid deposition in cholesterosis GBECs.  相似文献   
7.
Mesenchymal stem cells (MSCs) are non-hematopoietic cells with multi-lineage potential, which makes them attractive targets for regenerative medicine applications. Efficient gene transfer into MSCs is essential for basic research in developmental biology and for therapeutic applications involving gene-modification in regenerative medicine. Adenovirus vectors (Advs) can efficiently and transiently introduce an exogenous gene into many cell types via their primary receptors, the coxsackievirus and adenovirus receptors (CARs), but not into MSCs, which lack CAR expression. To overcome this problem, an Adv coated with cationic polymer polyethyleneimine (PEI) was developed. In this study, we demonstrated that PEI coating with an optimal ratio can enhance adenoviral transduction of MSCs without cytotoxicity. We also investigated the physicochemical properties and internalization mechanisms of the PEI-coated Adv. These results could help to evaluate the potentiality of the PEI-coated Adv as a prototype vector for efficient and safe transduction into MSCs.  相似文献   
8.
Imbalance between histone acetylation/deacetylation critically participates in the expression of hypertrophic fetal genes and development of cardiac hypertrophy. While histone deacetylases play dual roles in hypertrophy, current evidence reveals that histone acetyltransferase such as p300 and PCAF act as pro-hypertrophic factors. However, it remains elusive whether some histone acetyltransferases can prevent the development of hypertrophy. Males absent on the first (MOF) is a histone acetyltransferase belonging to the MYST (MOZ, Ybf2/Sas3, Sas2 and TIP60) family. Here in this study, we reported that MOF expression was down-regulated in failing human hearts and hypertrophic murine hearts at protein and mRNA levels. To evaluate the roles of MOF in cardiac hypertrophy, we generated cardiac-specific MOF transgenic mice. MOF transgenic mice did not show any differences from their wide-type littermates at baseline. However, cardiac-specific MOF overexpression protected mice from transverse aortic constriction (TAC)-induced cardiac hypertrophy, with reduced radios of heart weight (HW)/body weight (BW), lung weight/BW and HW/tibia length, decreased left ventricular wall thickness and increased fractional shortening. We also observed lower expression of hypertrophic fetal genes in TAC-challenged MOF transgenic mice compared with that of wide-type mice. Mechanically, MOF overexpression increased the expression of Catalase and MnSOD, which blocked TAC-induced ROS and ROS downstream c-Raf-MEK-ERK pathway that promotes hypertrophy. Taken together, our findings identify a novel anti-hypertrophic role of MOF, and MOF is the first reported anti-hypertrophic histone acetyltransferase.  相似文献   
9.
Interleukin-33 is a newly described member of the interleukin-1 family. Recent research suggests that IL-33 is increased in lungs and plays a critical role in chronic airway inflammation in cigarette smoke-induced chronic obstructive pulmonary disease (COPD) mice. To determine the role of IL-33 in systemic inflammation, we induced COPD mice models by passive cigarette smoking and identified the IL-33 expression in bronchial endothelial cells and peripheral blood mononuclear cells (PBMCs) of them. After isolation, PBMCs were cultured and stimulated in vitro. We measured expressions of interleukin-6 and interleukin-8 in PBMCs in different groups. The expression of IL-33 in bronchial endothelial cells and PBMCs of COPD mice were highly expressed. Stimulated by cigarette smoke extract (CSE), the expression of IL-6 and IL-8 were induced and enhanced by IL-33. PBMCs of COPD mice produced more IL-6 and IL-8 stimulated by CSE and IL-33. Expression of IL-6 and IL-8 were decreased when stimulated by IL-33 together with soluble ST2. The mRNA production of ST2 in IL-33 stimulated PBMCs was increased. Being pretreated with several kinds of MAPK inhibitors, the secretions of IL-6 and IL-8 in PBMCs did not decrease except for the p38 MAPK inhibitor. We found that IL-33 could induce and enhance the expression of IL-6 and IL-8 in PBMCs of COPD mice via p38 MAPK pathway, and it is a promoter of the IL-6 and IL-8 production in systemic inflammation in COPD mice.  相似文献   
10.

Background

Oral health has been found to be associated with cognitive function in basic research and epidemiology studies. Most of these studies had no comprehensive clinical diagnosis on cognitive function. This study firstly reported the association between tooth loss and cognitive function among Chinese older population.

Methods

The study included 3,063 community dwelling older adults aged 60 or above from the Shanghai Aging Study. Number of teeth missing was obtained from self-reporting questionnaire and confirmed by trained interviewers. Participants were diagnosed as “dementia”, “mild cognitive impairment (MCI)”, or “cognitive normal” by neurologists using DSM-IV and Petersen criteria. Multivariate logistic regression model was applied to examine the association between number of teeth missing and cognitive function.

Results

The study participants had an average of 10.2 teeth lost. Individuals with dementia lost 18.7 teeth on average, much higher than those with MCI (11.8) and cognitive normal (9.3) (p<0.001). After adjusted for sex, age, education year, living alone, body mass index, cigarette smoking, alcohol drinking, anxiety, depression, heart disease, hypertension, diabetes, and APOE-ε4, tooth loss of >16 were significantly associated with dementia with an OR of 1.56 (95%CI 1.12-2.18).

Conclusion

Having over 16 missing teeth was associated with severe cognitive impairment among Chinese older adults. Poor oral health might be considered as a related factor of neurodegenerative symptom among older Chinese population.  相似文献   
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