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Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. Hepatitis B virus X protein (HBx) contributes to the development of HCC, whereas HBx with COOH-terminal deletion is a frequent event in the HCC tissues. Previously, we identified a natural mutant of HBx-truncated 27 amino acids at the COOH-terminal (termed HBxDelta127), which strongly enhanced cell growth. In the present study, we focused on investigating the mechanism. Accordingly, fatty acid synthase (FAS) plays a crucial role in cancer cell survival and proliferation; thus, we examined the signaling pathways involving FAS. Our data showed that HBxDelta127 strongly increased the transcriptional activities of FAS in human hepatoma HepG2 and H7402 cells. Moreover, we found that 5-lipoxygenase (5-LOX) was responsible for the up-regulation of FAS by using MK886 (an inhibitor of 5-LOX) and 5-LOX small interfering RNA. We observed that HBxDelta127 could upregulate 5-LOX through phosphorylated extracellular signal-regulated protein kinases 1/2 and thus resulted in the increase of released leukotriene B4 (LTB4, a metabolite of 5-LOX) by ELISA. The additional LTB4 could upregulate the expression of FAS in the cells as well. Interestingly, we found that FAS was able to upregulate the expression of 5-LOX in a feedback manner by using cerulenin (an inhibitor of FAS). Collectively, HBxDelta127 promotes cell growth through a positive feedback loop involving 5-LOX and FAS, in which released LTB4 is involved in the up-regulation of FAS. Thus, our finding provides a new insight into the mechanism involving the promotion of cell growth mediated by HBxDelta127.

A method was developed for the determination of 6 p-hydroxybenzoates (methyl p-hydroxybenzoate (MHB), ethyl p-hydroxybenzoate (EHB), isopropyl p-hydroxybenzoate (IPHB), propyl p-hydroxybenzoate (PHB), isobutyl p-hydroxybenzoate (IBHB) and butyl p-hydroxybenzoate (BHB)) in fruits and jams using the combination of solid-phase extraction and high performance liquid chromatography (SPE-HPLC). Two different extraction solutions and three different mobile phases were tested for p-hydroxybenzoates analysis, and finally ethanol was used as the extraction solvent and methanol-citric acid buffer was selected as the mobile phase. The sample was extracted, and purified by an Oasis HLB solid-phase extraction cartridge, then separated on a Symmetry-C18 column and detected at the wave length of 258 nm. The results showed that all the calibration graphs were linear in the concentration range of 0.1 -20.0 mg/L (r = 0.9999). The detection limits and quantification limits were 0.1 mg/kg (S/N = 3) and 0.3 mg/kg (S/N = 10) respectively for MHB, EHB, IPHB and PHB, 0.2 mg/kg (S/N = 3) and 0.6 mg/kg (S/N = 10) respectively for IBHB and BHB. The average recoveries were between 82.8% and 115.5% with the relative standard deviations (RSDs) of 0.2%-6.8% (n = 6). The method is simple, rapid, sensitive and reproducible, and can be used for the routine analysis of the p-hydroxybenzoates in fruits and jams.

Water-soluble carboxymethyl chitosan was prepared from dried shrimp shells. The intrinsic viscosities of its samples were measured to evaluate the stability of carboxymethyl chitosan. The influential factors of stability, such as heat, pH, ionic strength, ultraviolet radiation, and sterilization were studied. The results demonstrate that the intrinsic viscosities of water-soluble chitosan will be influenced, to a certain extent, by the change of pH and ionic strength. Ultraviolet radiation and sterilized processes not only exept influence on the degradation of chitosan, but also have prominent effects on the molecular structure of it. Besides, temperature will also affect the speed of degradation, and chitosan can be stored at a temperature as low as 2 degrees C-8 degrees C.

Purpose: Autosomal dominant congenital cataract (ADCC) is a clinically and genetically heterogeneous lens disorder that usually presents as a sight-threatening trait in childhood. Here, we described a six-generation Chinese family presenting with morphologically homogeneous "nuclear pulverulent" cataracts., Methods: A whole genome scan was performed with polymorphic microsatellites in the Human MapPairs marker set, with special attention paid to known ADCC loci. Then we screened for mutations by direct sequencing., Results: A significantly positive two-point LOD score was obtained at marker D13S175(Zmax=7.83, theta=0). Haplotype analysis indicated this disease was located at 13q11, close to GJA3. Upon screening for mutations in GJA3 in this family, we found a novel transition mutation (TTC->TTA) resulting in a Phenylalanine-Leucine substitution at the highly conserved codon 32 of the GJA3 protein. This mutation segregated with the affected members of the family., Conclusions: This finding is the first report of a mutation in the first transmembrane region of GJA3. Our study further confirmed that GJA3 plays a vital role in the maintenance of human lens transparency.