Protective effect of Schisandra chinensis lignans on hypoxia-induced PC12 cells and signal transduction.

It is well-known that hypoxia induces neuronal injury; however, the mechanisms underlying this observed effect remain to be determined. Schisandra chinensis lignans (SCL). The aim of this study was thus to examine the ability of Schisandra chinensis lignans (SCL) to prevent hypoxia-induced neuronal injury using a human adrenal pheochromocytoma cell line (PC12). Exposure to hypoxia significantly reduced cell survival rate in cultured PC12 cells. However, pretreatment with SCL at 10, 20 or 40 µmol/L followed by hypoxia prevented loss of cellular viability. Flow cytometry demonstrated that the apoptotic rate in PC12 cells following hypoxia was significantly increased. Pretreatment with SCL 20 or 40 µmol/L in hypoxia-exposed cells resulted in significantly reduced apoptotic rates compared to hypoxia. Immunocytochemical staining showed that protein expression of p-Akt was significantly diminished by hypoxia. Following pre-treatment with different concentrations of SCL, PC12 cells were markedly stimulated as evidenced by elevated protein expression of p-Akt in a concentration-dependent manner. The expression of p-Akt protein in the presence of PI3K/Akt signaling pathway inhibitor LY294002 and SCL was not markedly changed indicating that signal transduction was affected by this Chinese herb. There were no significant differences in total Akt protein expression following hypoxia or pretreatment with SCL. Western blot demonstrated that expression levels of caspase-3 protein were significantly increased while expression levels of Bcl-2 protein were decreased in hypoxic cells. Pretreatment with SCL followed by hypoxia significantly lowered expression levels of caspase-3 protein accompanied by elevated expression levels of Bcl-2 protein in a concentration-dependent manner. After co-incubation with LY29004 and SCL, down-regulation of expression of caspase-3 protein and up-regulation of the expression of Bcl-2 protein noted with SCL alone were suppressed. Data suggest that the protective effect exerted by SCL in hypoxia-induced PC12 cell injury involves enhanced cell proliferation and inhibition of apoptosis mediated by activation of PI3K/Akt signaling pathway. The increased protein Akt phosphorylation expression levels resulted in consequent reduced downstream caspase-3 expression and enhanced Bcl-2 expression.

Long-term results of a prospective, randomized trial comparing retroperitoneoscopic partial versus total adrenalectomy for aldosterone producing adenoma.

PURPOSE: The indication for laparoscopic total or partial adrenalectomy in patients with aldosterone producing adrenal adenoma remains controversial. We compared retroperitoneoscopic partial and total adrenalectomy for aldosterone producing adrenal adenoma in a prospective, randomized, multicenter trial. MATERIALS AND METHODS: Patients with aldosterone producing adrenal adenoma were randomized to retroperitoneoscopic partial or total adrenalectomy. Patient characteristics, surgical data, complications and postoperative clinical results were analyzed statistically. RESULTS: From July 2000 to March 2004, 212 patients were enrolled in this study, including 108 and 104 who underwent total and partial adrenalectomy, respectively. The 2 groups were comparable in patient age, gender, body mass index and tumor site. Mean followup was 96 months in each group. No conversion to open surgery was needed and no major complications developed. Partial adrenalectomy required a shorter operative time than total adrenalectomy but this did not attain statistical significance. Intraoperative blood loss in the partial adrenalectomy group was significant higher than in the total adrenalectomy group (p <0.05) but no patient needed blood transfusion. All patients in each group showed improvement in hypertension, and in all plasma renin activity and aldosterone returned to normal after surgery. No patient required potassium supplements postoperatively. In the total and partial adrenalectomy groups 32 (29.6%) and 29 patients (27.9%), respectively, were prescribed a decreased dose of or fewer antihypertensive medicines at final followup. CONCLUSIONS: Retroperitoneoscopic partial adrenalectomy is technically safe. It has therapeutic results similar to those of total adrenalectomy in patients with primary aldosteronism due to aldosteronoma.

Wenxinia marina gen. nov., sp. nov., a novel member of the Roseobacter clade isolated from oilfield sediments of the South China Sea.

An aerobic and heterotrophic, Gram-negative bacterial isolate, strain HY34(T), was isolated from sediment of an oilfield in the South China Sea, China. The taxonomy of strain HY34(T) was studied by phenotypic and phylogenetic methods. Strain HY34(T) formed faint-pink colonies on marine agar 2216. Cells of strain HY34(T) were non-motile, ovoid or short rods. Strain HY34(T) was positive for catalase and oxidase, and nitrate was reduced to nitrite. The nearly complete 16S rRNA gene sequence of strain HY34(T) was obtained and sequence analysis showed that it, together with the genus Rubellimicrobium, formed a distinct clade close to some members of the Roseobacter clade in the family Rhodobacteraceae, and it showed highest sequence similarities to Oceanicola granulosus HTCC2516(T) (93.8 %), Silicibacter lacuscaerulensis ITI-1157(T) (93.3 %), Dinoroseobacter shibae DFL 12(T) (93.3 %) and Rubellimicrobium thermophilum C-lvk-R2A-2(T) (92.2 %). Bacteriochlorophyll a was not detected. The ubiquinone system was Q-10. The major polar lipids were phosphatidylglycerol, phosphatidylcholine and an unidentified glycolipid. The major fatty acids (>10 %) were C(18 : 1) omega 7c and C(16 : 0). The DNA G+C content of this strain was 69.4 mol%. A polyphasic analysis supported the conclusion that this strain represents a novel genus and species, which we designated Wenxinia marina gen. nov., sp. nov. The type strain of Wenxinia marina is HY34(T) (=CGMCC 1.6105(T) =JCM 14017(T)).

Cyclobacterium lianum sp. nov., a marine bacterium isolated from sediment of an oilfield in the South China Sea, and emended description of the genus Cyclobacterium.

The marine bacterial strain HY9(T) was isolated from sediment from the South China Sea. Strain HY9(T) is aerobic, heterotrophic and rose-pigmented. The cells are non-motile and curved, i.e. ring-like or horseshoe-shaped. The 16S rRNA gene sequence of strain HY9(T) was determined and blast searches revealed that it possessed significant sequence similarities with respect to Cyclobacterium species (92.8-93.6 %). Phylogenetic analysis confirmed that strain HY9(T) was tightly clustered with members of the genus Cyclobacterium. The cellular morphology and chemotaxonomic and phenotypic properties of strain HY9(T) showed that it should be classified as a member of the genus Cyclobacterium. Significant evolutionary distances and a range of phenotypic features distinguished strain HY9(T) from previously described Cyclobacterium species. Hence, strain HY9(T) represents a novel species in the genus Cyclobacterium, for which the name Cyclobacterium lianum sp. nov. is proposed. The type strain is HY9(T) (=CGMCC 1.6102(T)=JCM 14011(T)). On the basis of this study and previously described properties of Cyclobacterium species, an emended description of the genus Cyclobacterium is proposed.

[Bacterial conversion of sulfur-and phosphorous-compounds and microbial diversity in sediments from a near-shore marine-cultural region].

The H2S-producing bacteria and the phosphorous-cycling bacteria in sediments from near-shore marine-cultural region were investigated. Results indicate that the bacterial H2S production in aerobic condition is the dominating process to produce H2S in the sediment of cultural pond. The total counts of H2S-producing bacteria utilizing cysteine and Na2S2O3 were 1.6 x 10(6) and 4.35 x 10(3) cells g(-1) respectively. The counts of sulfate-reducing bacteria in the sediments were very little, only 2.5 x 10(1) g(-1). Further results show that the bacterial counts of decomposing lecithin and secreting phosphatase were 2.17 x 10(5) and 1.21 x 10(6) g(-1) respectively, bacterial counts of dissolving Ca3PO4 were 6.96 x 10(3) g(-1). Traditional taxonomy and partial 16S rRNA gene sequencing on the H2S-producing and phosphate-cycling bacteria indicate that most isolates could be classified as members of the following Genera: Bacillus, Halobacillus, Microbacterium, etc.