Luteimonas suaedae sp. nov., a novel bacterium isolated from rhizosphere of Suaeda aralocaspica (Bunge) Freitag & Schütze.

Light yellowish-white colonies of a bacterial strain, designated LNNU 24178T, were isolated from the rhizosphere soil of halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze grown at Shihezi district, Xinjiang, PR China. Cells were Gram-stain-negative, non-flagellum-forming, rod-shaped and non-motile. The results of phylogenetic analysis based on the 16S rRNA gene sequence indicated that LNNU 24178T represented a member of the genus Luteimonas and shared the highest sequence similarity with Luteimonas yindakuii CGMCC 1.13927T (97.1 %) and lower sequence similarity (< 97.0 %) to other known species. The genomic DNA G+C content of LNNU 24178T was 68.8 %. The average nucleotide identity (ANI) values between LNNU 24178T and Luteimonas yindakuii CGMCC 1.13927T, Luteimonas mephitis DSM 12574T, Luteimonas arsenica 26-35T and Luteimonas huabeiensis HB2T were 78.7, 78.6, 78.4 and 80.0 %, respectively. The digital DNA-DNA hybridisation (dDDH) values between LNNU 24178T and L. yindakuii CGMCC 1.13927T, L. mephitis DSM 12574T, L. arsenica 26-35T and L. huabeiensis HB2T were 22.0, 22.3, 22.2 and 23.5 %, respectively. The respiratory quinone detected in LNNU 24178T was ubiquinone-8 (Q-8). The major fatty acids (> 5.0 %) of LNNU 24178T were identified as iso-C15 : 0 (33.9 %), iso-C17 : 0 (8.7 %), iso-C11 : 0 (6.2 %), iso-C16 : 0 (5.7 %), C16 : 0 (5.3 %) and summed feature 9 (iso-C17 : 1ω9c/10-methyl C16 : 0) (21.1 %). The major polar lipids of LNNU 24178T were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), one unidentified phospholipid (PL), one unidentified glycolipid (GL) and three unidentified lipids. According to the data obtained from phenotypic, chemotaxonomic and phylogenetic analyses, strain LNNU 24178T represents a novel species of the genus Luteimonas, for which the name Luteimonas suaedae sp. nov. is proposed, with LNNU 24178T (= CGMCC 1.17331T= KCTC 62251T) as the type strain.

N-heterocyclic carbene catalyzed reaction of phthalaldehydes: controllable stereoselective synthesis of polyhydroxylated spiro- and fused indenones dictated by the structure of NHC catalysts.

The N-heterocyclic carbene catalyzed stereoselective dimerization reactions of phthalaldehydes produced polyhydroxylated spiro- or fused indenones. The reaction pathways were dictated by the structures of NHC catalysts. Under the catalysis of a imidazole carbene, phthalaldehydes produced dihydroxylspiro[indene-2,1'-isobenzofuran]-3-ones in good to excellent yields, whereas a triazole carbene catalyzed reaction of phthalaldehydes afforded fully cis-trihydroxylindeno[2,1-a]inden-5-ones in high yields. This work not only provides a highly efficient method for the construction of valuable polyhydroxyl substituted indene derivatives that are not easily assembled by other synthetic means but also reflects the versatility of organocatalysis using N-heterocyclic carbenes.

Multicomponent reaction of imidazo[1,5-a]pyridine carbenes with aldehydes and dimethyl acetylenedicarboxylate or allenoates: a straightforward approach to fully substituted furans.

The facile three-component reactions of N,N-substituted imidazo[1,5-a]pyridine carbenes, namely imidazo[1,5-a]pyridin-3-ylidenes, with aldehydes and DMAD or allenoates were disclosed. Both reactions proceeded via tandem nucleophilic addition, [3 + 2]-cycloaddition, and ring transformation to produce different 4-[(2-pyridyl)methyl]aminofuran derivatives generally in moderate yields. This work not only provided the first example of the application of imidazo[1,5-a]pyridin-3-ylidenes in organic synthesis but also developed a straightforward approach to fully substituted furans that are not easily accessible by other methods.

[Scavenger of reactive oxygen metabolites reverses the ROM induced inhibition of NK cell-mediated killing effect on K562 cell in vitro].

To investigate the effect of a new reactive oxygen metabolites (ROM) scavenger as immune adjuvant in NK cell-mediated killing effect on K562 cell, IL-2 and PHA were used to activate monocyte to produce ROM, and different concentrations of tiopronin as ROM scavenger was used in the cultivated systems with different ratio of monocytes plus NK cells and K562 cells, while histamine dihydrochloride (DHT) with different concentrations was used as positive control. The reuslts indicated that after IL-2 and PHA were supplemented in the cultivated systems mixing with NK cells and K562 cells as the E/T ratio was 10/1, the ROM production increased from 33.17 +/- 25.02 U/ml to 223.59 +/- 59.41 U/ml (P < 0.05) while K562 cell inhibition rate (KIR) increased from 65.56% to 85.89% (P < 0.05). When the monocytes as the E/MO ratios of 10/2, 10/5 and 10/10 were supplemented respectively, ROM production increased correspondingly (ROM production was 389.79 +/- 43.83 U/ml, 456.74 +/- 42.77 U/ml, 601.42 +/- 21.92 U/ml, respectively), and KIR was on the other round (KIR was 82.36%, 81.36%, 48.09% respectively). Tiopronin, DHT were used in the K562 + NK + MO + IL-2/PHA cultivated systems as the E/MO ratio was 10/2, the ROM production also decreased from 389.79 +/- 43.83 U/ml to -1.20 +/- 60.70 U/ml, 50.21 +/- 22.4 U/ml (P < 0.05), respectively, however KIR increased from 82.53% to 96.09% and 94.64% either (P < 0.05). Higher concentrations of tiopronin and DHT were used, ROM production decreased accordingly. There showed a reverse correlation between ROM production and KIR (r = -0.518). When E/MO ratio was 10/5 or 10/10, tiopronin at any testing concentration and DHT at the higher testing concentration could reduce the ROM production (P < 0.05), but did not improve KIR significantly (P > 0.05). Tiopronin was as good as DHT in ameliorating KIR (P > 0.05) and better than DHT in scavenging ROM (P < 0.05). It is concluded that (1) Monocytes are the major resources of ROM, and the ROM derived from monocytes can disable NK cells in killing neoplasm cells (K562 cells); (2) A new ROM scavenger, tiopronin, can scavenge ROM effectively, and reverse the ROM induced inhibition of NK cell-mediated killing of K562 cell in a certain extent. And tiopronin is better than DHT in scavenging ROM, and as good as DHT in up-regulating KIR. The new ROM scavenger tiopronin with less side effect may take the place of DHT as adjuvant during the adoptive immuno-therapy in leukemia.

[Effect of chronic intermittent hypoxia on hypoxia inducible factor-1alpha in mice].

OBJECTIVE: To explore the mechanism of the effect of chronic intermittent hypoxia (CIH), an important pathophysiological state of sleep apnea syndrome (SAS), on cardiovascular system. METHODS: Thirty male ICR mice were divided into three groups: an experimental group, an air mimic control group and a blank control group. Immunohistochemistry was used to examine the expression of hypoxia inducible factor-1alpha (HIF-1alpha) and inducible nitric oxide synthase (NOS-2) in the myocardial cells. Enzyme-linked immunosorbent assay (ELISA) was used to measure the plasma concentration of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1). RESULTS: The expression of HIF-1alpha in myocardial cells of the experimental group significantly increased compared with that of the air mimic control group (t = 3.54, P < 0.05), and that of the blank control group (t = 2.92, P < 0.05). The expression of HIF-1alpha in myocardial cells of the air mimic control group was not significantly different from that of the blank control group (P > 0.05). The plasma concentration of VEGF of the experimental group [(9.57 +/- 1.41) ng/ml] was significantly higher than that of the blank control group [(8.10 +/- 0.62) ng/ml, q = 4.27, P < 0.05], and that of the air mimic control group [(8.32 +/- 0.99) ng/ml, q = 3.64, P < 0.05]. While the plasma concentration of ET-1 of the experimental group [(3.31 +/- 0.81) ng/ml] was significantly higher than that of the blank control group [(2.50 +/- 0.72) ng/ml, q = 3.64, P < 0.05], it was not significantly different from that of the air mimic control group [(2.69 +/- 0.43) ng/ml, P > 0.05]. There was no significant difference between the expression of NOS-2 in myocardial cells of all groups (P > 0.05). CONCLUSION: CIH enhances the expression of HIF-1alpha and its target gene products VEGF and ET-1, and therefore affects the cardiovascular system.