Cloning and characterization of DELLA genes in Artemisia annua

Gibberellins (GA) are some of the most important phytohormones involved in plant development. DELLA proteins are negative regulators of GA signaling in many plants. In this study, the full-length cDNA sequences of three DELLA genes were cloned from Artemisia annua. Phylogenetic analysis revealed that AaDELLA1 and AaDELLA2 were located in the same cluster, but AaDELLA3 was not. Subcellular localization analysis suggested that AaDELLAs can be targeted to the nucleus and/or cytoplasm. Real-time PCR indicated that all three AaDELLA genes exhibited the highest expression in seeds. Expression of all AaDELLA genes was enhanced by exogenous MeJA treatment but inhibited by GA3 treatment. Yeast two-hybrid assay showed that AaDELLAs could interact with basic helix-loop-helix transcription factor AaMYC2, suggesting that GA and JA signaling may be involved in cross-talk via DELLA and MYC2 interaction in A. annua.

MTHFR A1298C polymorphism and ovarian cancer risk: a meta-analysis

Numerous studies have evaluated the association between the MTHFR A1298C polymorphism and ovarian cancer risk. However, the specific association is still controversial. Therefore, we performed the present meta-analysis. A systematic literature search of PubMed and Embase databases was undertaken in August 2014, and the reference lists of articles were retrieved. ORs with their 95%CI were calculated to evaluate the strength of the association. Meta-analysis was performed using the STATA version 12.0 software package and publication bias was investigated by Begg's funnel plot. Five case-control studies from three publications (with 7026 subjects) on the relationship between the MTHFR A1298C polymorphism and ovarian cancer were analyzed by meta-analysis. Overall, no significant variation in ovarian cancer risk was detected in any of the genetic models (AA vs CC: OR = 0.93, 95%CI = 0.78-1.10; AA vs AC: OR = 1.02, 95%CI = 0.92-1.13; dominant model: OR = 1.00, 95%CI = 0.91-1.10; recessive model: OR = 0.92, 95%CI = 0.78-1.08). In conclusion, this meta-analysis suggests that the A1298C polymorphism in the MTHFR gene may be not associated with susceptibility to ovarian cancer.

Association Between Urinary Phthalates and Pubertal Timing in Chinese Adolescents

BACKGROUND

Phthalates are synthetic chemicals and ubiquitous environmental contaminants, with hormonal activity that may alter the course of pubertal development in children.

OBJECTIVES

To determine whether exposure to phthalate metabolites is associated with timing of pubertal development in a cross-sectional study of a school-based clustered sample of 503 children from a suburban district in Shanghai, China, who were 7-14 years of age at enrollment (2010 October to November).

METHODS

We analyzed six phthalate metabolites in urine samples by isotope-dilution liquid chromatography tandem mass spectrometry. The associations of exposures to phthalates with pubertal timing of testes, breast, and pubic hair development (represented as Tanner stages) were evaluated using an ordered logistic regression model adjusted for chronological age, body fat proportion (BF%), and parental education.

RESULTS

In boys, urinary mono-n-butyl phthalate (MBP) levels were negatively associated with testicular volume, and mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) levels were negatively associated with pubic hair stages. The odds of being in an advanced stage were decreased by 43%-51%. In girls, mono (2-ethylhexyl) phthalate (MEHP), MEHHP, and MEOHP levels, as well as the sum of these levels, were positively associated with breast stages, and the association was much stronger in girls with high BF%; the odds of being in an advanced stage were increase by 29% to 50%.

CONCLUSIONS

Phthalate metabolites investigated in this study show significant associations with pubertal timing both in boys and in girls, especially among girls with high BF%.

Acute pulmonary embolism caused by highly aggregated intravenous immunoglobulin

BACKGROUND AND OBJECTIVES

Six patients died and one patient survived following infusion of a specific lot of intravenous immunoglobulin (IVIG) within half an hour in May 2008. This study elucidated the underlying pathogenesis.

MATERIALS AND METHODS

A variety of protein fractionation and identification approaches were employed to determine the abnormal components in IVIG products obtained from the hospital where the patients were treated. Animal studies using mice and monkeys were conducted to elucidate the pathophysiological mechanisms. In animal experiments, the effect and distribution of immunoglobulin was investigated using HE staining and immunohistochemistry (IHC) separately, while platelets and fibrinogen depletion were utilized to determine a possible link between thromboembolism formation in animals and the lethal effect of the IVIG. The size and distribution of the protein aggregates were determined with Coulter Counter Multisizer-3 after the dilution of the IVIG with plasma, and the lethal effect of the protein aggregates was simulated with artificial microparticles.

RESULTS

The IVIG retrieved from the hospital was found to have striking similarities to the heat-treated IVIG in terms of protein aggregation profiles and lethal effects. Post-mortem examination indicated that immunoglobulin aggregates were mainly found in the lung of the animals, while depletion of platelets and fibrinogen from the IVIG preparations failed to prevent the death of the animals. Similar amount of artificial microparticles caused animal death in similar fashion.

CONCLUSIONS

Our findings indicate that the retrieved IVIG exerted its lethal effects by blocking the pulmonary circulation without markedly altering the coagulation cascade or immunological events.

A Familial Cluster of Human Brucellosis Attributable to Contact with Imported Infected Goats in Shuyang, Jiangsu Province, China, 2013

Brucellosis remains a serious public health issue in developing countries, including China. On August 8, 2013, four cases of brucellosis from one extended family were reported at Shuyang County, Jiangsu Province, China. Active case finding was performed to identify the source and the risk factors of the infection and to prevent additional cases. Multiple-locus variable number tandem repeat analysis (MLVA) was used for molecular subtyping analysis. Six people from two extended families met the case definition for brucellosis infection; four were blood culture positive for Brucella melitensis biotype 3. Four additional family members were found seropositive by using a serological test. Isolates from the four patients were indistinguishable by MLVA profiling, displaying a unique type for Jiangsu Province. Field epidemiological data combined with MLVA genotyping supported a common source of the isolates from the different patients. We recommend stronger reinforcement measures for animal quarantine practices, enhanced cooperation with veterinary service organizations, and implementation of measures that strengthen public education on brucellosis to prevent further human outbreaks in Jiangsu Province.

Identification of circulating MicroRNAs as novel potential biomarkers for hepatocellular carcinoma detection: a systematic review and meta-analysis

BACKGROUND

MicroRNAs (miRNAs) in body fluids such as serum and plasma can be stably detected and used as potential biomarkers in hepatocellular carcinoma (HCC) diagnosis.

OBJECTIVE

To systematically evaluate circulating miRNAs from HCC expression profiling studies and to determine miRNA biomarkers for HCC detection.

METHODS

A systematic review and meta-analysis of published studies were carried out for comparing the circulating miRNA expressions between HCC patients and healthy people, hepatitis, or cirrhosis patients. A miRNA ranking system that considered the number of comparisons in agreement and total number of samples was used. Then the summary receiver-operating characteristic curve (sROC) results of the top miRNAs were combined to further evaluate their diagnostic value using Meta-disc 1.4.

RESULTS

In the 17 included studies, three circulating miRNAs (miR-21, miR-122, and miR-223) were repeatedly reported three times or more in both HCC patients vs. healthy controls and vs. other hepatitis or cirrhosis patients. In further analysis, the area under curve (AUC) of sROC for miR-21, miR-122 and miR-223 in discriminating HCC patients from healthy people are 0.9293, 0.8128, and 0.8597, respectively.

CONCLUSIONS

Circulating miR-21 has highest level of diagnostic efficiency among three miRNAs candidate biomarkers (miR-21, miR-122, and miR-223) for detection of HCC.

High reduction of interfacial charge recombination in colloidal quantum dot solar cells by metal oxide surface passivation

Bulk heterojunction (BHJ) solar cells based on colloidal QDs and metal oxide nanowires (NWs) possess unique and outstanding advantages in enhancing light harvesting and charge collection in comparison to planar architectures. However, the high surface area of the NW structure often brings about a large amount of recombination (especially interfacial recombination) and limits the open-circuit voltage in BHJ solar cells. This problem is solved here by passivating the surface of the metal oxide component in PbS colloidal quantum dot solar cells (CQDSCs). By coating thin TiO2 layers onto ZnO-NW surfaces, the open-circuit voltage and power conversion efficiency have been improved by over 40% in PbS CQDSCs. Characterization by transient photovoltage decay and impedance spectroscopy indicated that the interfacial recombination was significantly reduced by the surface passivation strategy. An efficiency as high as 6.13% was achieved through the passivation approach and optimization for the length of the ZnO-NW arrays (device active area: 16 mm2). All solar cells were tested in air, and exhibited excellent air storage stability (without any performance decline over more than 130 days). This work highlights the significance of metal oxide passivation in achieving high performance BHJ solar cells. The charge recombination mechanism uncovered in this work could shed light on the further improvement of PbS CQDSCs and/or other types of solar cells.

Hypoxia upregulates Rab11-family interacting protein 4 through HIF-1α to promote the metastasis of hepatocellular carcinoma

Hypoxic microenvironment is a powerful driving force for the invasion and metastasis of hepatocellular carcinoma (HCC). Hypoxia-inducible factor 1α (HIF-1α), as a crucial regulator of transcriptional responses to hypoxia, induces the expression of multiple target genes involved in different steps of HCC metastatic process. It is critical to find target genes associated with metastasis under hypoxia for shedding new light on molecular mechanism of HCC metastasis. In this study, we uncovered that hypoxia could induce the upregulation of Rab11-family interacting protein 4 (Rab11-FIP4) and activation of Rab11-FIP4 promoter by HIF-1α. The overexpression of Rab11-FIP4 significantly enhanced the mobility and invasiveness of HCC cells in vitro, also contributed to distant lung metastasis in vivo, whereas silencing of Rab11-FIP4 decreased the ability of migration and invasion in HCC cells in vitro and suppressed lung metastasis in vivo. Rab11-FIP4 facilitated HCC metastasis through the phosphorylation of PRAS40, which was regulated by mTOR. Furthermore, the expression level of Rab11-FIP4 was significantly increased in HCC tissues and high expression of Rab11-FIP4 was closely correlated with vascular invasion and poor prognosis in HCC patients. A markedly positive correlation between the expression of Rab11-FIP4 and HIF-1α was observed in HCC tissues and combination of Rab11-FIP4 and HIF-1α was a more valuable predictor of poor prognosis for HCC patients. In conclusion, Rab11-FIP4 is a target gene of HIF-1α and has a pro-metastatic role in HCC, suggesting that Rab11-FIP4 may be a promising candidate target for HCC treatment.

Dietary intake and phthalates body burden in boys and girls

Background

Phthalates are a group of environmental endocrine disruptors and have been ubiquitously applied in industrial field. Few studies had investigated how dietary intake was related with phthalate body burden in children.

To determine the relationship between phthalate body burden and dietary intake among school age children in Shanghai, China.

Methods

Four hundred and thirty schoolchildren aged 8–16 years were recruited in a cross-sectional study with 18 months follow-up in Shanghai, China during 2010–2012. Data of questionnaire-based dietary intake were collected and urinary phthalate concentrations were measured. Associations between frequency of dietary intake and phthalate metabolite concentrations were evaluated by stepwise multiple linear regression model.

Results

Positive association was found between mono-butyl phthalate and seafood, and negative associations were found between mono-butyl phthalate and dried fruits and vegetables. Egg consumption showed negative association with all di-(2-ethylhexyl) phthalate-related metabolites.

Conclusions

Some food types were identified to be associated with phthalate body burden and diet might be a source of phthalate exposure among Chinese schoolchildren.

Band engineering in core/shell ZnTe/CdSe for photovoltage and efficiency enhancement in exciplex quantum dot sensitized solar cells

Even though previously reported CdTe/CdSe type-II core/shell QD sensitizers possess intrinsic superior optoelectronic properties (such as wide absorption range, fast charge separation, and slow charge recombination) in serving as light absorbers, the efficiency of the resultant solar cell is still limited by the relatively low photovoltage. To further enhance photovoltage and cell efficiency accordingly, ZnTe/CdSe type-II core/shell QDs with much larger conduction band (CB) offset in comparison with that of CdTe/CdSe (1.22 eV vs 0.27 eV) are adopted as sensitizers in the construction of quantum dot sensitized solar cells (QDSCs). The augment of band offset produces an increase of the charge accumulation across the QD/TiO2 interface under illumination and induces stronger dipole effects, therefore bringing forward an upward shift of the TiO2 CB edge after sensitization and resulting in enhancement of the photovoltage of the resultant cell devices. The variation of relative chemical capacitance, Cμ, between ZnTe/CdSe and reference CdTe/CdSe cells extracted from impedance spectroscopy (IS) characterization under dark and illumination conditions clearly demonstrates that, under light irradiation conditions, the sensitization of ZnTe/CdSe QDs upshifts the CB edge of TiO2 by the level of ∼ 50 mV related to that in the reference cell and results in the enhancement of V(oc) of the corresponding cell devices. In addition, charge extraction measurements have also confirmed the photovoltage enhancement in the ZnTe/CdSe cell related to reference CdTe/CdSe cell. Furthermore, transient grating (TG) measurements have revealed a faster electron injection rate for the ZnTe/CdSe-based QDSCs in comparison with the CdSe cells. The resultant ZnTe/CdSe QD-based QDSCs exhibit a champion power conversion efficiency of 7.17% and a certified efficiency of 6.82% under AM 1.5 G full one sun illumination, which is, as far as we know, one of the highest efficiencies for liquid-junction QDSCs.

Anti-CD27 Antibody Potentiates Antitumor Effect of Dendritic Cell-Based Vaccine in Prostate Cancer-Bearing Mice

In the current study, we investigated whether anti-CD27 monoclonal antibody can enhance the antitumor efficacy of a dendritic cell-based vaccine in prostate cancer-bearing mice. The overall therapeutic effect of a dendritic cell-based vaccine for prostate cancer remains moderate. A prostate cancer model was established by subcutaneous injection of RM-1 tumor cells into male C57BL/6 mice on day 0. After 4 days, tumor-bearing mice were treated with RM-1 tumor lysate-pulsed dendritic cells (i.e., dendritic cell-based vaccine), anti-CD27 monoclonal antibody, or a combination of RM-1 tumor lysate-pulsed dendritic cells with anti-CD27 monoclonal antibody. Mice were killed at 21 days after tumor cell implantation. Tumor size was measured for assessment of antitumor effect. Spleens were collected for analysis of antitumor immune responses. The antitumor immune responses were evaluated by measuring the proliferation and activity of T cells, which have the ability to kill tumor cells. The combination therapy with RM-1 tumor lysate-pulsed dendritic cells and anti-CD27 antibody significantly enhanced T-cell proliferation and activity, and significantly reduced tumor growth, compared with monotherapy with RM-1 tumor lysate-pulsed dendritic cells or anti-CD27 antibody. Our results suggest that combined treatment can strengthen antitumor efficacy by improving T-cell proliferation and activity.

Electronic structures of two types of TiO2 electrodes: inverse opal and nanoparticulate cases

We present a comparison between the electronic structures of inverse opal (IO) and nanoparticulate (NP)-TiO₂ electrodes.

Controlled formation of barium fluoride nanocrystals by electric-assisted phase separation and precipitation

This work demonstrated that barium fluoride (BaF₂) nanocrystals can be controllably formed by an electric-assisted phase separation and precipitation method, EAPSP, in a water/ethanol mixture.

Hydrophilic interaction chromatography based solid-phase extraction and MALDI TOF mass spectrometry for revealing the influence of Pseudomonas fluorescens on phospholipids in salmon fillet

Salmon is a popular food but it is easily susceptible to spoilage by contamination with microorganisms. In this study, a method using hydrophilic interaction chromatography (HILIC)-based solid-phase extraction (SPE) and matrix-assisted laser desorption and ionization time-of-flight/time-of-flight mass spectrometry was developed and applied to reveal the effect of Pseudomonas fluorescens on salmon fillet during the shelf-life period by measuring the changes in the levels of phosphatidylcholine and phosphatidylethanolamine. Fresh samples were inoculated with P. fluorescens (10(6) cfu g(-1)) for 30 s, and lipids were extracted at 0, 24, 48, and 72 h. A homemade SPE cartridge packed with HILIC sorbent (silica derivatized with 1,2-dihydroxypropane) was used for matrix cleanup prior to analysis by mass spectrometry. In total, 30 phospholipids and 16 lysophospholipids were detected and elucidated. The results revealed that the content of phospholipids decreased significantly, whereas that of lysophospholipids increased initially, followed by a gradual reduction as the cold storage time increased. The contamination by P. fluorescens negatively affected the quality of fresh salmon without obvious physical changes, but it posed a potential threat to human health. This study suggests that the well-established method could be used for detecting phospholipids in salmon fillet and perhaps other foods as well.

[Study on tetrodotoxin detection and toxic puffer fish identification of roasted fish fillet at the retail in Beijing and Qingdao]

OBJECTIVE

The roasted fish fillet sample at the retail collected in Beijing and Qingdao were detected for TTX, and the TTX positive samples was analyzed for fish species identification.

METHODS

TTX was tested by EUSA method and the cytochrome c oxidase I (COI) genome of TTX-positive samples was extracted and identified by DNA barcode.

RESULTS

Totally, 90 samples were tested by EUSA and 58 (64.4%) samples were positive for TTX with the levels ranging from 0.10 mg/kg to 63.81 mg/kg. Among the TTX positive samples, 24 (41.3%) were identified containing toxic puffer fish and 21 (87.5%) were Lagocephalus lunaris, the highly toxic puffer fish.

CONCLUSION

Some roasted fish fillet samples obtained from the retail in two cities were positive for TTX and contained toxic puffer fish. Based on these results, we suggest that roasted fish fillet producers should prevent toxic puffer fish from mixing in the raw material and the I regulators should strengthen the TTX surveillance and product labeling supervision of roasted fish fillet.