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921.
The genome of a high lipid-producing fungus Mucor circinelloides WJ11 (36% w/w lipid, cell dry weight, CDW) was sequenced and compared with that of the low lipid-producing strain, CBS 277.49 (15% w/w lipid, CDW), which had been sequenced by Joint Genome Institute. The WJ11 genome assembly size was 35.4 Mb with a G+C content of 39.7%. The general features of WJ11 and CBS 277.49 indicated that they have close similarity at the level of gene order and gene identity. Whole genome alignments with MAUVE revealed the presence of numerous blocks of homologous regions and MUMmer analysis showed that the genomes of these two strains were mostly co-linear. The central carbon and lipid metabolism pathways of these two strains were reconstructed and the numbers of genes encoding the enzymes related to lipid accumulation were compared. Many unique genes coding for proteins involved in cell growth, carbohydrate metabolism and lipid metabolism were identified for each strain. In conclusion, our study on the genome sequence of WJ11 and the comparative genomic analysis between WJ11 and CBS 277.49 elucidated the general features of the genome and the potential mechanism of high lipid accumulation in strain WJ11 at the genomic level. The different numbers of genes and unique genes involved in lipid accumulation may play a role in the high oleaginicity of strain WJ11.  相似文献   
922.
Resistance to cisplatin-based chemotherapy is a major cause of treatment failure in advanced bladder cancer (BC) patients. There is increasing evidence that microRNAs are involved in the development and progression of BC. However, little is known about the function of microRNAs in predicting the effect of adjuvant chemotherapy on BC survival and regulating response to cisplatin. To address this issue, we employed RT-qPCR to evaluate the clinical significance of miR-203 expression in 108 tissues of BC patients receiving cisplatin-based adjuvant chemotherapy, and performed in vitro studies to explore chemotherapeutic sensitivity to cisplatin in miR-203 overexpressing BC cells. We found miR-203 levels were significantly lower in BC progression group than non-progression group (P<0.001). ROC curve analysis illustrated miR-203 could significantly distinguish progressed patients from those without progression (P<0.001), yielding an area under the ROC curve of 0.839 (95% CI, 0.756–0.903). Moreover, low miR-203 expression correlated with shortened progression free survival (PFS) and overall survival (OS) of BC patients, and was an independent prognostic factor. Overexpression of miR-203 in 5637 and T24 BC cells could decrease cell viability, enhance cisplatin cytotoxicity, and promote apoptosis. Western blotting and luciferase reporter assay showed Bcl-w and Survivin were direct downstream targets of miR-203. There was also a significant inverse association between miR-203 and Bcl-w or Survivin expression in BC tissues (r = -0.781, -0.740, both P<0.001). In conclusion, decreased miR-203 predicts progression and poor prognosis for BC patients treated with cisplatin-based chemotherapy while miR-203 overexpression can enhance cisplatin sensitization by promoting apoptosis via directly targeting Bcl-w and Survivin.  相似文献   
923.

Background

The increasingly recognized importance of vitamin D has been discussed and vitamin D status among young children has attracted widespread attention in recent years. However, study on vitamin D status in young children aged 1–3 y is limited in China.

Objective

To evaluate the nutritional vitamin D status of young children aged 1–3 y in Wuxi, southeastern China.

Methods

A large cohort of 5,571 young children aged 1–3 y were recruited in this study who visited the child health clinics at the Wuxi Maternity and Child Health Hospital (latitude 31.57°N) during January 2014 to January 2015. Wuxi was located in southeastern China at a latitude of 31.57°N. Finger-stick blood sampling was conducted in all the subjects and serum 25-Hydroxyvitamin D (25(OH)D) levels were measured to evaluate their vitamin D status.

Results

In this study, serum 25(OH)D levels of young children at the age of 1–3 years ranged from 20.6–132.9 nmol/L (Median: 71.5 nmol/L). 16.1% of the population had vitamin D deficiency (<50 nmol/L), while 38.8% of the subjects had a sufficient (50–74.9 nmol/L) vitamin D level. An optimal vitamin D status (≥75 nmol/L) was found in 45.1% of the young children. The prevalence of vitamin D deficiency was higher in autumn (19.5%) than in summer (12.1%). There was no significant difference in vitamin D status between genders. The binary logistic regression analysis revealed that child age was strongly associated with vitamin D deficiency (adjusted OR: 1.173; 95%CI: 1.053–1.308; P = 0.004).

Conclusions

The prevalence of vitamin D deficiency was 16.1% among young children aged 1–3 y in Wuxi. Season and child age were associated with their vitamin D status. It is implied that young children should receive adequate amounts of vitamin D supplementation and spend more time outdoors to prolong the sunlight exposure when they grow older.  相似文献   
924.
The aim of the present study was to compare the changes in the levels of 27 aqueous humor cytokines between diabetic patients with macular edema (ME) and diabetic patients without ME. Undiluted aqueous humor samples were obtained from 68 consecutive type 2 diabetic patients without ME and 56 consecutive type 2 diabetic patients with ME. The concentrations of 27 cytokines in the aqueous humor samples were measured using a multiplex bead immunoassay. Compared with diabetic patients without ME, diabetic patients with ME had significantly higher concentrations of IL-1β, IL-6, IL-8, IP-10, MCP-1, and VEGF in the aqueous humor. However, the concentrations of IL-10 and IL-12 were significantly lower in the diabetic patients with ME. The aqueous humor levels of IL-1β, IL-6, IL-8, MCP-1, IP-10, and VEGF were closely correlated with retinal macular thickness, retinal macular volume and the severity of ME. In addition, the aqueous humor levels of IL-10 and IL-12 decreased with increasing the severity of ME. A variety of cytokines associated with inflammation and angiogenesis may contribute to the pathogenesis of diabetic macular edema, and both anti-inflammatory and antiangiogenic agents should be included in the treatment of ME simultaneously.  相似文献   
925.
Rotaviruses (RVs) are an important cause of severe gastroenteritis in children. It has been found that RV may recognize the histo-blood group antigens (HBGAs) as ligands or receptors and bind HBGAs in a type-dependent manner. In this study, we investigated the binding specificity of VP8* proteins from human rotaviruses (RV) that are prevalent in China including genotypes P[4], P[6], and P[8]. Through the saliva- and oligosaccharide-based binding assays, we found that the VP8* proteins of P[4] and P[8] RV showed similar reactivity with the Leb and H type 1 antigens, while P[6] RV weakly bound the Leb antigen. These findings may facilitate further research into RV host specificity and vaccine development.  相似文献   
926.

Background and Objectives

Carotid artery stenting (CAS) is an important therapeutic strategy for patients with carotid artery stenosis. However, the potential influence of CAS on cognitive function in patients with carotid artery stenosis and cerebral lacunar infarction has not been determined. This study investigated changes in cognitive function associated with CAS and the factors related to these changes.

Methods

This prospective cohort study comprised 579 Chinese patients with cerebral lacunar infarction and carotid artery stenosis for whom CAS was indicated, and a matched control group of 552 healthy individuals. Cognitive function before CAS and at scheduled intervals from 6 months to 3 years was assessed with instruments that included the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scale. Potential factors that might affect cognitive function were analyzed via logistic regression.

Results

The MMSE and MoCA scores of the patients before CAS were significantly lower than that of the control subjects. These scores were significantly higher 6 months after CAS and sustained or increased throughout the 3-year follow-up. Also significantly improved after CAS from baseline were scores for an alternating trail test, cube copying, clock-drawing, attention, and delayed recall in an auditory-verbal learning test. Logistic regression analyses showed that age greater than 65 y, little education, diabetes, and hypertension were independent risk factors for deteriorated MoCA scores 3 years after CAS.

Conclusion

CAS was associated with significantly improved cognitive function in cerebral lacunar infarction patients with severe stenosis.  相似文献   
927.
Face recognition is challenging especially when the images from different persons are similar to each other due to variations in illumination, expression, and occlusion. If we have sufficient training images of each person which can span the facial variations of that person under testing conditions, sparse representation based classification (SRC) achieves very promising results. However, in many applications, face recognition often encounters the small sample size problem arising from the small number of available training images for each person. In this paper, we present a novel face recognition framework by utilizing low-rank and sparse error matrix decomposition, and sparse coding techniques (LRSE+SC). Firstly, the low-rank matrix recovery technique is applied to decompose the face images per class into a low-rank matrix and a sparse error matrix. The low-rank matrix of each individual is a class-specific dictionary and it captures the discriminative feature of this individual. The sparse error matrix represents the intra-class variations, such as illumination, expression changes. Secondly, we combine the low-rank part (representative basis) of each person into a supervised dictionary and integrate all the sparse error matrix of each individual into a within-individual variant dictionary which can be applied to represent the possible variations between the testing and training images. Then these two dictionaries are used to code the query image. The within-individual variant dictionary can be shared by all the subjects and only contribute to explain the lighting conditions, expressions, and occlusions of the query image rather than discrimination. At last, a reconstruction-based scheme is adopted for face recognition. Since the within-individual dictionary is introduced, LRSE+SC can handle the problem of the corrupted training data and the situation that not all subjects have enough samples for training. Experimental results show that our method achieves the state-of-the-art results on AR, FERET, FRGC and LFW databases.  相似文献   
928.
929.
930.
Psoriasis is considered a systemic inflammatory disorder. Previous studies have reported conflicting positive or negative correlations between psoriasis and chronic obstructive pulmonary disease. We performed a meta-analysis to determine whether there is an associated risk between psoriasis and chronic obstructive pulmonary disease. We performed a complete 30-year literature search of MEDLINE, Embase, and Cochrane Central Register databases on this topic. Four observational studies with a total of 13,418 subjects were identified. The odds ratios of chronic obstructive pulmonary disease in subjects with psoriasis/mild-to-moderate psoriasis were analyzed using the random-effects model, while the odds ratios of chronic obstructive pulmonary disease in subjects with severe psoriasis and current smoking in subjects with psoriasis were analyzed using the fixed-effect model. We found that psoriasis patients were at a greater risk of developing chronic obstructive pulmonary disease than the general population (odds ratio, 1.90; 95% confidence interval, 1.36–2.65) and that the association between of psoriasis and with chronic obstructive pulmonary disease was stronger among patients with severe psoriasis (odds ratio, 2.15; 95% confidence interval, 1.26–3.67). Psoriasis patients should be advised to cease smoking to reduce their risk of COPD. Moreover, identification of this potential risk may enable earlier implementation of preventive measures for reduction comorbidity and mortality rates.  相似文献   
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