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Yong Tao

Publications and source records attributed to Yong Tao.

At least 19 recordsLinked to original sources
PubMed2006

Profiling Caenorhabditis elegans non-coding RNA expression with a combined microarray.

Small non-coding RNAs (ncRNAs) are encoded by genes that function at the RNA level, and several hundred ncRNAs have been identified in various organisms. Here we describe an analysis of the small non-coding transcriptome of Caenorhabditis elegans, microRNAs excepted. As a substantial fraction of the ncRNAs is located in introns of protein-coding genes in C.elegans, we also analysed the relationship between ncRNA and host gene expression. To this end, we designed a combined microarray, which included probes against ncRNA as well as host gene mRNA transcripts. The microarray revealed pronounced differences in expression profiles, even among ncRNAs with housekeeping functions (e.g. snRNAs and snoRNAs), indicating distinct developmental regulation and stage-specific functions of a number of novel transcripts. Analysis of ncRNA-host mRNA relations showed that the expression of intronic ncRNA loci with conserved upstream motifs was not correlated to (and much higher than) expression levels of their host genes. Even promoter-less intronic ncRNA loci, though showing a clear correlation to host gene expression, appeared to have a surprising amount of 'expressional freedom', depending on host gene function. Taken together, our microarray analysis presents a more complete and detailed picture of a non-coding transcriptome than hitherto has been presented for any other multicellular organism.

Animals↗
PubMed2006

Removal of methanol from pulp and paper mills using combined activated carbon adsorption and photocatalytic regeneration.

Methanol is one of the major hazardous air pollutants emitted from chemical pulp mills. Its collection and treatment is required by the Maximum Achievable Control Technology portion of the 1998 Cluster Rule. The objective of this study is to investigate the technical feasibility of combined adsorption and photocatalytic regeneration for the removal and destruction of methanol. To facilitate the regeneration, activated carbon (AC) was coated with commercially available photocatalyst by a spray desiccation method. Laboratory-scale experiments were conducted in a fixed-bed reactor equipped with an 8 W black light UV lamp (peak wavelength at 365 nm) at the center. The photocatalyst loaded onto AC had no significant impact on the adsorption capacity of the carbon. High humidity was found to greatly reduce the material's capacity in the adsorption and simultaneous adsorption and photocatalytic oxidation of methanol. The photocatalytic regeneration process is limited by the desorption of the adsorbate. Increasing desorption rate by using purge air greatly increased the regeneration capacity. When the desorption rate was greater than the photocatalytic oxidation rate, however, part of the methanol was directly desorbed without degradation.

Adsorption↗
PubMed2006

Cloning and expression of a chitinase gene from Sanguibacter sp. C4.

The chitinase Chi58 is an extracellular chitinase produced by Sanguibacter sp.strain C4. The gene-specific PCR primers were used to detect the presence of the chiA gene in strain C4. A chiA fragment (chiA-F) was amplified from the C4 genomic DNA and was used to blast-search the related sequences from the GenBank database. By alignment and selection of the highly conserved regions of the homologous sequences, two pairs of primers were designed to amplify the open reading frame (ORF) of the chitinase from strain C4 by nested PCR. The results revealed that the Chi58 ORF consisted of 1 692 nucleotides encoding a protein of 563 amino acid residues. The molecular weight of the mature protein was predicted to be 58.544 kDa. The Chi58 ORF was a modular enzyme composed of a signal peptide sequence, a polycystic kidney disease I domain, and a glycosyl hydrolase family 18 domain. The chitinase of C4 exhibited a high level of similarity to the chitinase A of Serratia (88.9%-99.6%) at the amino acid sequence level. The Chi58 gene was cloned into the expression vector pET32a to construct the recombinant plasmid pChi58 and was expressed in E. coli BL-21 (DE3) cells with IPTG induction. The molecular weight of the Trx-Chi58 fusion protein was estimated to be 81.1 kDa by SDS-PAGE.

Actinomycetales↗
PubMed2006

Cytokinin represses phosphate-starvation response through increasing of intracellular phosphate level.

The involvement of cytokinins (CTKs) in the repression of phosphate (Pi)-starvation signalling has been widely documented. However, the full physiological and molecular relevance of this role remains unclear. To gain further insights into the regulation system of CTK repression of Pi-starvation signalling, a global analysis of gene expression events in rice seedlings under Pi starvation, and the exogenous CTK treatment under Pi-sufficient (+P) and Pi-deficient (-P) conditions, was conducted using oligonucleotide array analysis. Physiological and biochemical adaptation was observed after 10 d Pi starvation in rice seedlings. A global reduction of the Pi-starvation signalling was detected after 3 d treatment of exogenous CTK. Expression profiling data indicate that, together with a significant increase of intracellular Pi content, many expression changes responsive to Pi starvation were reversed by exogenous CTK treatment while CTK-responsive genes behaved normally under -P condition. These results suggest that the interplay of CTK signal and Pi-starvation response can be partially explained by the rise of Pi concentration after exogenous CTK treatment. Microarray data also revealed that a small number of genes have different CTK response patterns under different Pi levels, suggesting a subtle interaction between CTK and Pi-starvation signalling pathway.

Cytokinins↗
PubMed2006

[Careful use of radial optic neurotomy for the treatment of retinal central vein occlusion].

Radial optic neurotomy (RON) is an attractive and controversy procedure. Commenting on some disputed issues, the authors think that it seems inappropriate to negate the therapeutic effects of RON completely. However, it should be careful to select the proper patients for performing the RON. The indiscriminate extension of the indications of RON should be avoided.

Contraindications↗
PubMed2005

Purification and properties of a novel insecticidal protein from the locust pathogen Serratia marcescens HR-3.

One or more proteinaceous factors with insecticidal activities in the locust pathogen Serratia marcescens HR-3 culture filtrates were found to cause the death of grassland locusts. A novel insecticidal protein was purified to homogeneity. It was a monomer of 61 kDa. The purified protein showed a strong insecticidal effect with a median lethal dosage of 12.1 microg locust(-1) and contained a high level of protease activity (101 U ml(-1)). Insecticidal activity was significantly decreased when the protein was pretreated with ethylene diamine tetraacetic acid and 1-10-phenanthroline, and it was restored when the treated protein was incubated with Zn(2+). The N-terminal amino acid sequence of insecticidal protein showed sequence similarity with metalloprotease from S. marcescens SM6 and Serratia spp. E15. Our results suggested that the factor primarily responsible for insecticidal activity toward locusts was a zinc-dependent 61-kDa metalloprotease.

Amino Acid Sequence↗
PubMed2005

Gene expression profiling in rice young panicle and vegetative organs and identification of panicle-specific genes through known gene functions.

In rice, at the stage from pistil and stamen primordia formation to microsporocyte meiosis, the young panicle organs (YPO) make a great contribution to grain productivity. This period corresponds to the onset of meiosis and marks the transition from vegetative to reproductive stages. By comparing gene expression profiling of YPO with that of rice aerial vegetative organs (AVO), it is possible to gain further molecular insight into this period that is developmentally and functionally important. In this report, a total of 92,582 high-quality ESTs from 5'-end sequencing, including 44,247 from YPO and 48,335 from AVO, were obtained and classified. There were 12,884 (29.12%) ESTs from YPO and 16,304 (33.73%) ESTs from AVO matched to known genes, which generated 1,667 and 2,172 known genes, respectively, after integration of these ESTs. From the functions of known homologous genes, we identified some tissue- and developmental-stage-specified genes in YPO. The expression of these genes clearly reflected the unique functional characteristics of YPO. Furthermore, we estimated that there are about 10,000 mRNAs specifically expressed in rice YPO.

DNA Primers↗
PubMed2005

Theoretical and experimental design of atypical kinase inhibitors: application to p38 MAP kinase.

Mimics of the benzimidazolone nucleus found in inhibitors of p38 kinase are proposed, and their theoretical potential as bioisosteres is described. A set of calculated descriptors relevant to the anticipated binding interaction for the fragments 1-methyl-1H-benzotriazole 5, 3-methyl-benzo[d]isoxazole 3, and 3-methyl-[1,2,4]triazolo[4,3-a]pyridine 4, pyridine 1, and 1,3-dimethyl-1,3-dihydro-benzoimidazol-2-one 2 are reported. The design considerations and synthesis of p38 inhibitors based on these H-bond acceptor fragments is detailed. Comparative evaluation of the pyridine-, benzimidazolone-, benzotriazole-, and triazolopyridine-based inhibitors shows the triazoles 20 and 25 to be significantly more potent experimentally than the benzimidazolone after which they were modeled. An X-ray crystal structure of 25 bound to the active site shows that the triazole group serves as the H-bond acceptor but unexpectedly as a dual acceptor, inducing movement of the crossover connection of p38alpha. The computed descriptors for the hydrophobic and pi-pi interaction capacities were the most useful in ranking potency.

Benzimidazoles↗
PubMed2005

Atrial natriuretic peptide negatively regulates follicle-stimulating hormone-induced porcine oocyte maturation and cumulus expansion via cGMP-dependent protein kinase pathway.

This study examined the effect of atrial natriuretic peptide (ANP) on porcine cumulus-enclosed oocyte (CEO) maturation and cumulus expansion. ANP negatively regulated follicle-stimulating hormone (FSH)-stimulated germinal vesicle breakdown (GVBD; 90.1, 81.2 and 68.2% for FSH, FSH+10nM ANP and FSH+1 microM ANP, respectively), first polar body emission (PB1; 86.1, 75.3 and 53.3% for FSH, FSH+1 nM ANP and FSH+1 microM ANP, respectively) and cumulus expansion (CEI; 3.47, 3.16 and 2.43 for FSH, FSH+1 nM ANP and FSH+1 microM ANP, respectively) in a dose-dependent manner when CEOs were cultured in the maturation medium containing porcine follicular fluid (pFF). This negative effect showed a time-dependent manner after preincubation with 100 nM ANP for 5h (78.4% PB1), 10h (81.7% GVBD and 74.1% PB1), 20 h (78.5% GVBD and 68.9% PB1), and 44 h (75.3% GVBD and 60.5% PB1), respectively. ANP also significantly inhibited FSH-induced porcine oocyte GVBD (47.6% versus 83.8%) and PB1 emission (22.4% versus 45.2%) when CEOs were cultured in pFF-free maturation medium. cGMP analog 8-Br-cGMP (10 microM to 1mM) mimicked the effects of ANP on GVBD, PB1, and CEI. The negative effect of ANP was completely reversed by KT5823 (a specific inhibitor of cGMP-dependent protein kinase), while C-ANP-(4-23) (an analogue of ANP and specific binder for natriuretic peptide receptors-C) was ineffective in oocyte maturation. Neither ANP nor C-ANP-(4-23) had an effect on spontaneous porcine oocyte maturation and cumulus expansion. These results suggested that ANP negatively regulates FSH-activated porcine oocyte meiotic resumption, meiotic maturation and cumulus expansion. The function of ANP on porcine oocyte maturation is via the cGMP dependent protein kinase (PKG) pathway.

Animals↗
PubMed2005

Fundus and histopathological study of radial optic neurotomy in the normal miniature pig eye.

OBJECTIVE: To demonstrate the fundus and histopathological changes in the normal miniature pig eye after radial optic neurotomy. METHODS: Ophthalmoscopic examinations, fundus photography, and fluorescein angiography were performed on 12 eyes that underwent radial optic neurotomy, 5 normal eyes, and 7 eyes that underwent vitrectomy (from 12 pigs in total) preoperatively and 1, 7, 14, 30, and 90 days postoperatively. These eyes were enucleated 120 days postoperatively. Sixteen eyes (of 8 pigs in total) that underwent radial optic neurotomy were enucleated 1, 3, 7, and 48 days (2 pigs each time) postoperatively. The enucleated eye sections were stained with hematoxylin-eosin, Masson trichrome, and Luxol fast blue. RESULTS: The retina radial to the site of radial optic neurotomy darkened gradually with the increasing curvature of the major retinal arteries. The filling time intervals from the retinal artery to the retinal vein were prolonged. At the incision site, there was a loss of nerve fibers, which were subsequently replaced by collagenous tissue. No anastomotic vessels formed by the end of the study. CONCLUSIONS: Postoperatively, the retinal circulation seemed somewhat sluggish compared with that seen preoperatively. Segmental retinal nerve atrophy eventually formed. The procedure itself may not be the sole factor for the formation of shunt vessels. CLINICAL RELEVANCE: To date, radial optic neurotomy is controversial and persuasive animal studies are lacking. In combining fluorescein angiography with histopathological examination, this study may be somewhat helpful.

Animals↗
PubMed2005

Effects of nitric oxide synthase inhibitors on porcine oocyte meiotic maturation.

As an important biological messenger, nitric oxide (NO) exhibits a wide range of effects during physiological and pathophysiological processes, including mammalian oocyte meiotic maturation. The present study investigated whether NO derived from two nitric oxide synthase (NOS) isoforms, inducible NOS (iNOS) or endothelial NOS (eNOS), is involved in the meiotic maturation of porcine oocytes. Meanwhile, the cumulus cells' function in meiotic maturation and their interaction with oocyte development and degeneration were also investigated using cumulus-enclosed oocytes (CEOs) and denuded oocytes (DOs). Different inhibitors for NOS were supplemented to the medium. Cumulus expansion, cumulus cell DNA fragmentation and oocyte meiotic resumption were evaluated 48 h after incubation. Aminoguanidine (AG), a selective inhibitor for iNOS, suppressed cumulus expansion and inhibited CEOs to resume meiosis (p < 0.05), but did not inhibit cumulus cell DNA fragmentation. Both Nomega-nitro-L-arginine (L-NNA) and Nomega-nitro-L-arginine methyl ester (L-NAME), inhibitors for both iNOS and eNOS, delayed cumulus expansion, inhibited cumulus cell DNA fragmentation and inhibited CEOs to resume meiosis. Such effects were not seen in DOs. These results indicate that iNOS-derived NO is necessary for cumulus expansion and meiotic maturation by mediating the function of the surrounding cumulus cells, and eNOS-derived NO is also involved in porcine meiotic maturation.

Animals↗
PubMed2005

[Isolation and identification of a Streptomyces strain against ginger bacterial wilt caused by Pseudomonas solanacearum Smith].

Streptomyces SR-11 was isolated from the soil of ginger in Sichuan Province against ginger bacterial wilt caused by Pseudomonas solanacearum Smith. It had distinctively inhibitive effect on gram-positive bacterium, gram-negative bacterium and some kinds of pathogenic fungi. It's morphological, cultural physiological, biochemical characteristics, chemotaxonomy and 16S rDNA sequences analysis were studied. The substrate mycelium have no partition, the aerial mycelium are ramose; The spore-bearing filaments are spiral, the spores are oval and the surface are smooth. Cell wall type I, Sugar type C. When SR-11 is matured, the aerial mycelium are gray and the strain can give out an earthy smell. A phylogenetic tree was constructed by comparing with the published 16S rDNA sequences of the related bacteria species. In the phylogenetic tree the overall similarity value between strain SR-11 and 12 type Streptomyces sp are 96.5-98.3%.

DNA, Bacterial↗
PubMed2005

[Identification of a pathogenic strain of locusts and its toxicity and pathology].

A pathogen was isolated from naturally dead grasshoppers. Its pathogenicity was testified by law of KOCH. It was identified as Serratia marcescens by physiological, biochemical test and molecular systematic analysis. Toxicity of HR-3 to grasshoppers was assayed by means of oral infection. The results show that the linear regression relationship between the logarithm(y) of HR-3 concentration and the probability (x) of corrected grasshopper morality is y = 1.067 + 0.809x, and the median lethal concentration is LC50 = 1.164 x 10(8) cfu/mLo The infection mechanism of HR-3 to grasshoppers were also studied. The histopathological studies show that midgut epithelia are damaged at the beginning of infection, and then partial denaturalization and putrescence occurr in this area. After 48h infection, vacuoles appear in most regions of midgut epithelia.

Animals↗
PubMed2005

[Current status of radial optic neurotomy in the treatment of central retinal vein occlusion].

There is no definitely proven effective managements of central retinal vein occlusion to date. Much attention has been paid for radial optic neurotomy, although it is not accepted widely as a regular surgery, the improvement of fundus appearance was observed in some cases after surgery indeed. In this paper, we reviewed the case selective criterion, surgery method, surgery lancet, effectiveness and possible mechanism of this surgery.

Fundus Oculi↗
PubMed2005

[Analysis of audiological assessment and hearing aid evaluation results from 13 deaf children].

OBJECTIVE: To investigate why the ideal objective cannot be met after deaf children are fitted with hearing aids. METHOD: Complete audiological assessment and hearing aid check were done on 13 deaf children filled with hearing aids. RESULT: Two children were found to have otitis media with effusion and myringitis respectively. All hearing aids were matched improperly with inappropriate fit. CONCLUSION: After deaf children are fitted with hearing aids, they should be followed-up on a regular base in order to monitor their hearing and to check whether they wear the hearing aids properly with a proper fit. All people in the field of aural rehabilitation for deaf children should realize the importance of the correct way to wear hearing aids with correct adjustment.

Child↗
PubMed2004

A novel class of inhibitors of peptide deformylase discovered through high-throughput screening and virtual ligand screening.

Peptide deformylase (PDF) has been identified as a promising antibacterial and herbicide target. A structurally novel class of inhibitors containing a 2-thioxo-thiazolidin-4-one heterocycle substituted by an arylidene group at the 5-position and a hexanoic acid side chain at the 3-position was discovered independently via high-throughput screening and virtual ligand screening. Data mining and analogue synthesis established a structure--activity relationship for the side chain region that is consistent with the docked structure.

Amidohydrolases↗
PubMed2004

Nitric oxide influences the maturation of cumulus cell-enclosed mouse oocytes cultured in spontaneous maturation medium and hypoxanthine-supplemented medium through different signaling pathways.

Nitric oxide (NO) has been recently shown to act with a dual action in mouse oocyte meiotic maturation depending on its concentration, but the mechanism(s) through which it influences oocyte maturation has not been fully clarified to date. The purpose of this study was to test the hypothesis that different signaling mechanisms exist for NO-stimulated and NO-inhibited in vitro maturation of meiosis in cumulus cell-enclosed oocytes (CEOs) from PMSG-primed immature female mice. CEOs were cultured in both spontaneous maturation model and hypoxanthine (HX) arrested model to investigate the mechanism(s). Sodium nitroprusside (SNP, an NO donor) at a concentration of 1mM delayed significantly germinal vesical breakdown (GVBD) during the first 5 h of incubation period and further inhibited the formation of first polar body (PB1) at the end of 24 h of incubation. While SNP, at a concentration of 10 microM, stimulated significantly the meiotic maturation of oocytes by overcoming the inhibition of HX. Methinine blue (MB, 10 microM) or 1-H-[1,2,4] oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ, 10 microM)), two soluble guanylate cyclase (sGC) inhibitors, could reverse SNP-inhibited spontaneous oocyte maturation, but had no effect on SNP-stimulated meiotic maturation in the presence of HX. 8-Br-cGMP (1mM), a cell-permeating cGMP analogue, demonstrated a significant inhibitory effect on both spontaneous meiotic maturation and HX-arrested meiotic maturation. The delay effect of SNP on GVBD occurrence was similar to that of forskolin (6 microM, an adenylate cyclase stimulator) and rolipram (250 microM, a phosphodiesterase 4 inhibitor), two cAMP elevating reagents. Both forskolin and rolipram reversed significantly the SNP-stimulated meiotic maturation, but did not reverse the SNP-inhibited spontaneous meiotic maturation. Cilostamide (1 microM), the selective inhibitor of phosphodiestrase 3 (PDE3), could mimic the inhibitory effect of HX on the spontaneous meiotic maturation in CEOs and this inhibitory effect could also be reversed by SNP (10 microM). Moreover, sphingosine (3 microM), a protein kinase C (PKC) inhibitor, blocked the SNP-inhibited spontaneous meiotic maturation, but did not block the SNP-stimulated meiotic maturation. Clearly, these results suggest that pathway differences are present between SNP-inhibited spontaneous meiotic maturation and SNP-stimulated meiotic maturation of mouse oocytes.

Animals↗