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During the life cycle of shellfish, larval development, especially metamorphosis, has a vital influence on the dynamics, distribution, and recruitment of natural populations, as well as seed breeding. Rapana venosa, a carnivorous gastropod, is an important commercial shellfish in China, and is an ecological invader in the United States, Argentina, and France. However, information about the mechanism of its early development is still limited, because research in this area has long suffered from a lack of genomic resources. In this study, 15 digital gene expression (DGE) libraries from five developmental stages of R. venosa were constructed and sequenced on the IIIumina Hi-Sequation 2500 platform. Bioinformaticsanalysis identified numerous differentially and specifically expressed genes, which revealed that genes associated with growth, nervous system, digestive system, immune system, and apoptosis participate in important developmental processes. The functional analysis of differentially expressed genes was further implemented by gene ontology, and Kyoto encyclopedia of genes and genomes enrichment. DGE profiling provided a general picture of the transcriptomic activities during the early development of R. venosa, which may provide interesting hints for further study. Our data represent the first comparative transcriptomic information available for the early development of R. venosa, which is a prerequisite for a better understanding of the physiological traits controlling development. [ABSTRACT FROM AUTHOR]

Background: To prospectively compare strain ratio to elastography score system in distinguishing between malignant and benign thyroid nodules. Methods: The local institutional review board approved the study, and all patients provided written informed consent. We examined 168 thyroid nodules (52 malignant and 116 benign) with freehand elastography. The elastogram was performed with both the five-degree elastography score system and thyroid tissue-to-nodule strain ratio before core biopsies as standard reference. The area under the curve (AUC) and the best cut-off point were both obtained using receiver-operating characteristic (ROC) curve analysis. The sensitivity, specificity, and accuracy of both techniques were compared with the א²test. Furthermore, strain ratio distribution was also compared with histopathological result. P<.05 was considered to indicate significance. Results: The strain ratio distribution of malignant thyroid nodules significantly differed from that of benign nodules (all P<.001). The AUC of strain ratio was higher than that of the elastography score system (0.907 vs. 0.829; P<.05). By applying the best cut-off point of 3.855 for strain ratio and 3.5 for the elastography score system, strain ratio had significantly higher specificity (P<.05) in detecting malignant thyroid nodules. However, there was no significant difference in the sensitivity in distinguishing malignant thyroid nodules from benign ones between strain ratio and the elastography score system (P>.05). Conclusion: Strain ratio is more specific than conventional elastography score system in differentiating malignant from benign thyroid nodules. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD) is a rapidly growing health threat that has previously been associated with lipogenesis. The direct effect of endoplasmic reticulum stress (ERS) inhibition on the induction of lipogenesis has not been investigated in hepatocytes in vitro. The impact of activating transcription factor-4 (ATF4) on the lipogenic pathway and hepatic insulin transduction in liver cells also requires further investigation. In the present study, the triglyceride (TG) content of HepG2 cells stimulated with fructose was investigated using a commercially available enzymatic assay, and the expression levels of lipogenesis-associated factors were determined by western blotting and reverse transcription-quantitative polymerase chain reaction. Notably, the TG content of HepG2 cells was increased following incubation with fructose, which was accompanied by ERS. 4-Phenylbutyric acid, an inhibitor of ERS, lowered the TG content by reducing the mRNA expression levels of sterol regulatory element-binding protein 1 (SREBP-1c) and carbohydrate-responsive element-binding protein (ChREBP), and the protein expression levels of fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC) and stearoyl-CoA desaturase-1 (SCD-1). Conversely, tunicamycin, which is an inducer of ERS, increased the TG content and stimulated the expression of the above lipogeneic markers. ATF4 deficiency relieved TG accumulation and decreased the mRNA expression levels of SREBP-1c and ChREBP, and protein expression levels of FAS, ACC and SCD-1 in fructose-treated HepG2 cells. Conversely, ATF4 overexpression increased the TG content by upregulating the mRNA expression levels of SREBP-1c and ChREBP and protein expression levels of FAS, ACC and SCD-1. Inhibition of ERS was shown to protect HepG2 cells against fructose-induced TG accumulation, whereas induction of ERS stimulated hepatic lipogenesis. As a downstream transcription factor of the unfolded protein response, a deficiency in ATF4 attenuates fructose-induced lipogenesis; while an overexpression of ATF4 can induce TG accumulation through stimulating hepatic lipogenesis. The results of the present study suggested that ATF4 may exert various physiological roles in lipid metabolism depending on the nutrient composition. In addition, these results suggested that ATF4 has a role in regulating lipogenesis and in the development of NAFLD; thus ATF4 may be considered a therapeutic target for NAFLD. [ABSTRACT FROM AUTHOR]