甘草质膜水通道蛋白GuPIP1对甘油的转运

旨在进行甘草质膜水通道蛋白GuPIP1对水和溶质通透性的鉴定.将GuPIP1全长编码区的cDNA构入非洲爪蟾卵母细胞检测系统的表达栽体psp64 Poly(A),并将体外转录获得GuPI1的cRNA显微注射入卵母细胞,使GuPIP1基因在卵母细胞中表达,通过测定卵母细胞对水和溶质的转运功能来鉴定GuPIP1的转运功能.结果表明,GuPIP1在异源表达系统非洲爪蟾卵母细胞中具水和甘油通透性,但不能转运尿素,为探讨GuPIP1在植株生理中的作用奠定基础.     

Endotoxin removing method based on lipopolysaccharide binding protein and polyhydroxyalkanoate binding protein PhaP

Polyhydroxyalkanoates (PHAs) granule associated protein PhaP has a strong affinity to PHA and other hydrophobic polymers. Human lipopolysaccharide binding protein (hLBP) is a natural endotoxin receptor in plasma. In this study, genes encoding hLBP fused with PhaP were expressed in Pichia pastoris GS115 for production of the fusion protein. The purified rhLBP-PhaP fusion protein was immobilized on particles of polyhydroxybutyrate (PHB), which is a member of microbial polyhydroxyalkanoates (PHA). The rhLBP-PhaP-coated PHB particles were added to endotoxin containing water and protein solutions to study their endotoxin removal and protein recovery efficiencies. The influences of ionic strengths and pH on endotoxin removal and protein recovery in different protein solutions were also studied using acidic proteins including bovine serum albumin (BSA), ovalbumin, and basic protein α-chymotrypsinogen as model proteins. The results showed that rhLBP-PhaP particles could remove endotoxin with an efficiency of over 90%. All endotoxin removal and protein recovery efficiencies were only slightly affected by ionic strengths but were drastically affected by pH changes. Our results demonstrated that rhLBP-PhaP particles with their high efficiency, ease of preparation, and nontoxicity will be a suitable system for endotoxin removal in the protein purification industry.     

Synthesis of novel derivatives of esculentoside A and its aglycone phytolaccagenin, and evaluation of their haemolytic activity and inhibition of lipopolysaccharide-induced nitric oxide production

A series of 46 compounds derived from esculentoside A and its aglycone were synthesized and characterized. The effect of these compounds on lipopolysaccharide (LPS)-induced NO production, haemolytic activity, and cell viability was evaluated. Structure-activity relationship was established by comparing the derivatives of esculentoside A with its aglycone derivatives. Both the aglycone and its derivatives showed higher inhibitory effects on LPS-induced NO production, and lower haemolytic activities than esculentoside A and its derivatives.     

Microarray analysis of differentially expressed microRNAs in non-regressed and regressed bovine corpus luteum tissue; microRNA-378 may suppress luteal cell apoptosis by targeting the interferon gamma receptor 1 gene

MicroRNAs (miRNAs) are small non-coding endogenous RNA molecules that down-regulate the expression of target genes in a sequence-dependent manner. Recent studies indicated that miRNAs are mechanistically involved in the regulation of the mammalian corpus luteum (CL). However, few studies have profiled the different miRNA expression patterns in bovine non-regressed and regressed CL. In this study, miRNA microarray was employed to investigate the different miRNA expression patterns in bovine CL. Among the 13 differentially expressed miRNAs, seven were preferentially expressed in non-regressed CL, while six miRNAs were more highly expressed in regressed CL. Real-time RT-PCR was used to validate the microarray results. Mir-378 miRNA, known to be associated with apoptosis, was 8.54-fold (P < 0.01) up-regulated in non-regressed CL, and the interferon gamma receptor 1 (IFNGR1) gene, which potentially plays a role in apoptosis of the luteal cell, was predicted to be the target of mir-378. The results of real-time RT-PCR of mir-378 and western blot analysis of the IFNGR1 protein at different stages of CL development showed that mir-378 decreased the expression of IFNGR1 protein but not IFNGR1 mRNA. Taken together, our data support a direct role for miRNA in apoptosis of bovine CL.     

Microbial transformation of neoandrographolide by Mucor spinosus (AS 3.2450)

Microbial transformation of neoandrographolide (1), was performed by Mucor spinosus (AS 3.2450). Ten metabolites were obtained and identified as 14-deoxyandrographolide (2), 17,19-dihydroxy-8,13-ent-labdadien-16,15-olide (3), 3,14-dideoxyandrographolide (4), 7β-hydroxy-3,14-dideoxyandrographolide (5), 17,19-dihydroxy-7,13-ent-labdadien-16,15-olide (6), 8(17),13-ent-labdadien-16,15-olid-19-oic acid (7), 8α,17β-epoxy-3,14-dideoxyandrographolide (8), 8β,17,19-trihydroxy-ent-labd-13-en-16, 15-olide (9), phlogantholide-A (10), 19-[(β-d-glucopyranosyl)oxy]-19-oxo-ent-labda-8(17),13-dien-16,15-olide (11) by spectroscopic and chemical means. Among them, products 3, 5, 6, 8 and 9 were characterized as new compounds. The inhibitory effects of compounds 1–11 on nitric oxide production in lipopolysaccharide-activated macrophages were evaluated and their preliminary structure–activity relationships (SAR) were discussed.     

On the phylogeny of Mustelidae subfamilies: analysis of seventeen nuclear non-coding loci and mitochondrial complete genomes

Background  

Mustelidae, as the largest and most-diverse family of order Carnivora, comprises eight subfamilies. Phylogenetic relationships among these Mustelidae subfamilies remain argumentative subjects in recent years. One of the main reasons is that the mustelids represent a typical example of rapid evolutionary radiation and recent speciation event. Prior investigation has been concentrated on the application of different mitochondrial (mt) sequence and nuclear protein-coding data, herein we employ 17 nuclear non-coding loci (>15 kb), in conjunction with mt complete genome data (>16 kb), to clarify these enigmatic problems.     

Y-like retinal ganglion cells innervate the dorsal raphe nucleus in the Mongolian gerbil (Meriones unguiculatus)

Background

The dorsal raphe nucleus (DRN) of the mesencephalon is a complex multi-functional and multi-transmitter nucleus involved in a wide range of behavioral and physiological processes. The DRN receives a direct input from the retina. However little is known regarding the type of retinal ganglion cell (RGC) that innervates the DRN. We examined morphological characteristics and physiological properties of these DRN projecting ganglion cells.

Methodology/Principal Findings

The Mongolian gerbils are highly visual rodents with a diurnal/crepuscular activity rhythm. It has been widely used as experimental animals of various studies including seasonal affective disorders and depression. Young adult gerbils were used in the present study. DRN-projecting RGCs were identified following retrograde tracer injection into the DRN, characterized physiologically by extracellular recording and morphologically after intracellular filling. The result shows that DRN-projecting RGCs exhibit morphological characteristics typical of alpha RGCs and physiological response properties of Y-cells. Melanopsin was not detected in these RGCs and they show no evidence of intrinsic photosensitivity.

Conclusions/Significance

These findings suggest that RGCs with alpha-like morphology and Y-like physiology appear to perform a non-imaging forming function and thus may participate in the modulation of DRN activity which includes regulation of sleep and mood.     

Investigation of bacterial community diversity in water of Zoige Alpine Wetland

Spatial isolation is currently thought to represent one of the major factors resulting in bacteria genetic variation and population abundance. The bacterial diversity in a distinct environment Zoige Alpine Wetland located in the northeast of the Qinghai-Tibetan Plateau with the altitude 3400 m on average aroused our great attention. This area belongs to Qinghai-Tibetan cold climate zone with the mean annual temperature about 1 °C. Although several studies on bacterial diversity in Qinghai-Tibetan Plateau had been reported, there is no report on wetland water in this area. In this work, six water samples were collected and the water qualities including COD_Cr, NH₄⁺-N, NO₃^--N, NO₂^--N, TN, TP, TOC were investigated, of which results indicated that more than 80% samples sorted as II–V class of surface water sources according to the National Water Quality Standard of China (GB3838-2002). Comparison of bacterial communities among the six samples was analyzed by DGGE of PCR-amplified 16S rDNA with universal bacterial primer sets. The profiles demonstrated that samples from the Flower Lake had more DNA bands than the Conservatory Station inferring higher diversity. In addition, the samples from the same environment shared similar compositions of bacterial communities. Bacterial community composition and predominant bacteria were analyzed by 16S rDNA clone library. The dominant group was Proteobacteria (51.6% of the total clones, which contained 24.2% alpha proteobacteria, 14.5% beta proteobacteria and 12.9% gamma proteobacteria). And the Bacteroidetes added to 17.7%, Verrucomicrobia to 4.8%. More than 24.2% of the total clones showed high similarity to uncultured bacteria. The above work provides some information on bacterial diversity for special site of spatial isolation.     

Use of the D-R model to define trends in the emergence of Ceftazidime-resistant Escherichia coli in China

Objective

To assess the efficacy of the D-R model for defining trends in the appearance of Ceftazidime-resistant Escherichia coli.

Methods

Actual data related to the manifestation of Ceftazidime-resistant E. coli spanning years 1996–2009 were collected from the China National Knowledge Internet. These data originated from 430 publications encompassing 1004 citations of resistance. The GM(1,1) and the novel D-R models were used to fit current data and from this, predict trends in the appearance of the drug-resistant phenotype. The results were evaluated by Relative Standard Error (RSE), Mean Absolute Deviation (MAD) and Mean Absolute Error (MAE).

Results

Results from the D-R model showed a rapid increase in the appearance of Ceftazidime-resistant E. coli in this region of the world. These results were considered accurate based upon the minor values calculated for RSE, MAD and MAE, and were equivalent to or better than those generated by the GM(1,1) model.

Conclusion

The D-R model which was originally created to define trends in the transmission of swine viral diseases can be adapted to evaluating trends in the appearance of Ceftazidime-resistant E. coli. Using only a limited amount of data to initiate the study, our predictions closely mirrored the changes in drug resistance rates which showed a steady increase through 2005, a decrease between 2005 and 2008, and a dramatic inflection point and abrupt increase beginning in 2008. This is consistent with a resistance profile where changes in drug intervention temporarily delayed the upward trend in the appearance of the resistant phenotype; however, resistance quickly resumed its upward momentum in 2008 and this change was better predicted using the D-R model. Additional work is needed to determine if this pattern of “increase-control-increase” is indicative of Ceftazidime-resistant E. coli or can be generally ascribed to bacteria acquiring resistance to drugs in the absence of alternative intervention.