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MicroRNA-9 (miR-9) has been shown to promote the differentiation of bone marrow mesenchymal stem cells into neuronal cells, but the precise mechanism is unclear. Our previous study confirmed that increased autophagic activity improved the efficiency of neuronal differentiation in bone marrow mesenchymal stem cells. Accumulating evidence reveals that miRNAs adjust the autophagic pathways. This study used miR-9-1 lentiviral vector and miR-9-1 inhibitor to modulate the expression level of miR-9. Autophagic activity and neuronal differentiation were measured by the number of light chain-3 (LC3)-positive dots, the ratio of LC3-II/LC3, and the expression levels of the neuronal markers enolase and microtubule-associated protein 2. Results showed that LC3-positive dots, the ratio of LC3-II/LC3, and expression of neuron specific enolase and microtubule-associated protein 2 increased in the miR-9(+) group. The above results suggest that autophagic activity increased and bone marrow mesenchymal stem cells were prone to differentiate into neuronal cells when miR-9 was overexpressed, demonstrating that miR-9 can promote neuronal differentiation by increasing autophagic activity.

To develop multiplex reverse translation-polymerase chain reaction (RT-PCR) method for detection of dengue virus type 1-4.Based on the genomes sequence analysis of dengue virus type 1-4, four-pair of primers were designed. The specificity of the primers was primarily tested by searching the GenBank DNA sequence database. The optimal reaction conditions of the multiplex RT-PCR were then established. The specificity of RT-PCR was tested using the homologous yellow fever virus and Japanese encephalitis virus. 30 serum samples of dengue virus from suspected sufferers in the prevalence of dengue virus in 2003 were detected using the methods we developed.Positive segments about 295, 237, 118, 347 bp could be seen in the multiplex RT-PCR production of dengue virus type 1-4, respectively. There were no positive segments in the RT-PCR productions of Japanese encephalitis virus and yellow fever virus. 25 of the 30 serum samples showed dengue virus type 1 positive results, while the sequencing results suggesting the amplification sequence having a high homology with dengue virus type 1 strain Cambodia, GD14/97 and GD05/99 (97%, 97%, 98%, respective).The method of multiplex RT-PCR we established could be used for early detection and identification of dengue virus type 1-4.

Excellent inbred-lines of maize,340 and 4112, which were used largely in hybridized combination were transformed with Agrobacterium tumefaciens. The immature embryos and their original calli were infected by A.tumefaciens LBA4404 containing plasmid pGBIL04. After 3 days of co-cultivation, the immature embryos and calli were continuously selected on the medium containing phosphinothricin (PPT) for 3 generations, then plants were regenerated. It was proved by PCR analysis that the target Bt gene had been integrated into the genome of regenerated plants. The results showed that fresh original calli from the immature embryos after pre-culture were suitable acceptors. The results also showed that it could increase the frequency of selection by properly lowering the co-culture temperature to 22 degrees .

Sperm-egg plasma membrane interaction is one of the important steps of mammalian fertilization. Many sperm and egg surface proteins are reported to be involved in sperm-zona pellucida interaction. Sulfogalactosylglycerolipid(SGG) is the major sulfoglycolipid in the germ cells of mammalian and lower vertebrates, mainly in the sperm head. It is a differentiation marker in spermatogenesis restricted to the zygotene and early pachytene spermatocytes. Sulfolipidimmobilizing protein 1 (SLIP1) is the major sulfoglycolipid of mammalian germ cells and eggs, with the same localization as SGG in the sperm. SLIP1 binds specificity to SGG, both playing a vital role in sperm-egg interaction. This article is aimed at reviewing the localization of SGG and SLIP1 in the germ cell surface and their role and related mechanism in gamete formation.

To detect the cholesterol ester transfer protein (CETP) levels in semen of infertile patients and evaluate the correlation between CETP in semial plasma and infertility.One hundred and sixty-three infertile patients and fifteen fertile males were selected randomly. The routine examination of ejaculates was fulfilled by computer aided semen analysis (CASA). The CETP levels in all seminal plasma samples and fifty-five serum samples were detected by ELISA method.The CETP levels in infertile patients and fertile males were (2.21 +/- 1.23) microgram/L and (1.40 +/- 0.45) microgram/L, respectively. There were no significant differences between the two groups(P0.05). And there were no significant differences of CETP levels in seminal plasma among groups of azoospermia(n = 29), oligoasthenozoospermia (n = 58), oligospermia(n = 15), asthenozoospermia(n = 44) and normozoospermia(n = 17) in the infertile patients(P0.05). The CETP in seminal plasma and serum were detected in 55 infertile patients, and there was no correlation between CETP levels in seminal plasma and serum using Spearman analysis(r = 0.009, P0.05). The mean CETP level in seminal plasma was almost 1/1,000 of that in serum.The CETP level in seminal plasma is extremely low and has no relation with the changes of sperm density or motility. It may ensure the integrity of sperm membrane before the sperm enters into female genital tract.

Background: Sequencing and annotation of the genome of rice (Oryza sativa) have generated gene models in numbers that top all other fully sequenced species, with many lacking recognizable sequence homology to known genes. Experimental evaluation of these gene models and identification of new models will facilitate rice genome annotation and the application of this knowledge to other more complex cereal genomes. Results: We report here an analysis of the chromosome 10 transcriptome of the two major rice subspecies, japonica and indica, using oligonucleotide tiling microarrays. This analysis detected expression of approximately three-quarters of the gene models without previous experimental evidence in both subspecies. Cloning and sequence analysis of the previously unsupported models suggests that the predicted gene structure of nearly half of those models needs improvement. Coupled with comparative gene model mapping, the tiling microarray analysis identified 549 new models for the japonica chromosome, representing an 18% increase in the annotated protein-coding capacity. Furthermore, an asymmetric distribution of genome elements along the chromosome was found that coincides with the cytological definition of the heterochromatin and euchromatin domains. The heterochromatin domain appears to associate with distinct chromosome level transcriptional activities under normal and stress conditions. Conclusion: These results demonstrated the utility of genome tiling microarrays in evaluating annotated rice gene models and in identifying novel transcriptional units. The tiling microarray analysis further revealed a chromosomewide transcription pattern that suggests a role for transposable element-enriched heterochromatin in shaping global transcription in response to environmental changes in rice.

Strychnos nux-vomica L. has been frequently used in traditional Chinese medicine but has high acute toxicity. It is commonly taken with Glycyrrhizae radix to decrease its toxicity but the mechanism of this interaction is unknown. In this work, the mRNA expression and the activity of four cytochrome P450 (CYP) enzymes representative of four subfamilies (CYP1A, CYP3A, CYP2C and CYP2E) were determined ex vivo in rat livers from groups of Wistar rats orally administered strychnine hydrochloride (SH) at three doses (0.1, 0.3 and 0.9 mg/kg/day) alone and, at the highest dose, in combination with glycyrrhetinic acid (GA, 25 mg/kg/day) or liquiritin (LQ, 20 mg/kg/day) once a day for 7 consecutive days. Compared to control, the mRNA expressions of CYP3A1, 1A2 and 2E1 were higher in rats receiving the highest dose of SH but lower for CYP3A1 and CYP2E1 in rats receiving the SH+GA and SH+LQ combinations. CYP2E1 activity was higher and CYP2C, CYP3A and CYP1A2 activities were lower in rats receiving the highest dose of SH. In contrast CYP1A2 and CYP2C activities were higher and CYP2E1 and CYP3A activities lower in rats receiving the SH+GA combination. CYP2E1 and CYP3A activities were also lower in rats receiving the SH+LQ combination. The results show that treatment with SH for 7 days affects the expression and the activity of CYP enzymes and that coadministration of GA and LQ modulates these effects. This modulation may explain the role of Glycyrrhizae radix in reducing the acute toxicity of Strychnos nux-vomica L.CYPs enzymes.