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Biomedical subjects

Y Fu

Publications and source records attributed to Y Fu.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Studies of the origin of Chinese domestic fowls].

A total of 539 bases fragment of mitochondrial DNA D-loop region of six domestic chicken breeds (30 individuals) were sequenced and compared to that of red junglefowl, grey junglefowl, green junglefowl and Lafayette's junglefowl issued in GenBank, and the phylogenetic trees for the chickens constructed based on the D-loop sequences. The results indicated that the four species of genus Gallus had great differences between each other, the G. g. domesticus was the next of kin to red junglefowl in Thailand and its adjacent regions, and near of kin to red junglefowl in Indonesian, Lafayette's junglefowl, grey junglefowl and green junglefowl one by one in proper order, suggesting that the red junglefowl in Thailand and its neighbour areas sufficed as the matriarchic ancestor of Chinese domestic fowls. It was also discovered that the two subspecies of Thailand i.e. G. g. gallus and G. g. spadiceus should belong to one subspecies because of their far lower differentiation compared to that among the domestic breeds.

Animals↗
PubMed2001

[Studies of genetic diversity of Zhejiang native chicken breeds].

A total of 539 bases of mitochondrial DNA D-loop region of five native chicken breeds of Zhejiang province and the white leghorn chicken (as the control) were sequenced by DNA sequencing technique, and the phylogenetic trees of the chicken breeds were constructed. The results showed that 24 variation sites i.e. 4.45% sequence divergence were detected among the 30 DNA sequences, and the six breeds belonged to two different maternal lineage, one included Xianju chicken and White Leghorn chicken which had the same maternal origin, the other included Lingkun chicken, Baiyiner chicken, Wugu chicken and Xiaoshan chicken which had the same matriarchic ancestor. Among the latter lineage, Lingkun chicken, Baiyiner chicken and Wugu chicken had a closer relationship to each other than to Xiaoshan chicken.

Animals↗
PubMed2001

[cDNA cloning and mRNA expression pattern in follicles of the mature inhibin alpha subunit from Xianju chicken].

The mature region of Xianju chicken inhibin alpha-subunit was amplified from the total RNA of follicle granulosa cells by RT-PCR using the primer pair designed according to the reported cDNA sequence of chicken inhibin alpha-subunit, and this fragment of alpha-subunit was cloned and sequenced subsequently. The results revealed that the mature alpha-subunit of Xianju chicken was a fragment of 113 amino acids containing one glycosylation site and seven cysteine residues. It was approximately 98% and 61.4%-68.7% identical in nucleotide sequence, 97.3% and 64.6%-69% similar in deduced amino acid sequence, respectively, in the mature region to the chicken and mammalian inhibin alpha-subunit cDNA clone. As for the mature chicken inhibin alpha-subunit, the number of potential glycosylation site and cysteine residues was the same, and their corresponding positions in the amino acid sequences were almost identical as compared to chicken and mammalian inhibin alpha-subunit, which indicated that the inhibin alpha-subunit was highly conserved among different species, implying an important role of inhibin alpha-subunit in various animals. The quantitative analysis of competitive RT-PCR for inhibin alpha-subunit revealed that the expression of alpha-subunit decreased with further follicle maturity from SYF to F1 follicle. The highest level of inhibin alpha-subunit mRNA was found in the SYF and F6-8 follicles, which indicated that inhibin alpha-subunit played an important role during the course of follicular recruitment, selection and dominance.

Amino Acid Sequence↗
PubMed2001

[Expression pattern of mRNA for follistatin and inhibin/activin beta B-subunit during follicular and testicular development in duck].

Follistatin and inhibin/activin were closely related glycoprotein hormones. The quantitative competitive RT-PCR was used to investigate the expression of follistatin and inhibin/activin beta B-subunit mRNA in the developing ovarian follicles, immature and mature testes. The results revealed all samples showed the expression of mRNA for the two proteins, and the expression is more abundantly in the small follicles than in the large preovulatory follicles. Competitive RT-PCR revealed that the expression of follistatin is the highest in small yellow follicles (SYF), the mean relative content for the F1, F2, F3, F4, F5, F6-8, LWF (large white follicle), TI(immature testes), and TM(mature testes) was 0.011 +/- 0.004, 0.019 +/- 0.006, 0.021 +/- 0.009, 0.028 +/- 0.007, 0.075 +/- 0.023, 0.15 +/- 0.072, 0.29 +/- 0.068, 0.037 +/- 0.011, and 0.012 +/- 0.004, respectively, compared to a mean relative content of 1.00 for the SYF. The highest level of inhibin/activin beta B mRNA was also found in the SYF, the mean relative content for the F1, F2, F3, F4, F5, F6-8, LWF, TI, and TM was 0.009 +/- 0.003, 0.013 +/- 0.005, 0.019 +/- 0.007, 0.023 +/- 0.006, 0.29 +/- 0.084, 0.84 +/- 0.093, 0.031 +/- 0.008, 0.38 +/- 0.072, and 0.046 +/- 0.013, respectively, compared to a mean relative content of 1.00 for the SYF. Our data suggested that the expression pattern of mRNA for follistatin and inhibin/activin beta B-subunit was quite similar during follicular and testicular development. The great co-expression of mRNA for the two proteins in small follicles indicated that activin B(beta B-beta B) availability was tightly regulated by follistatin, and the two proteins might both play important roles in early follicular development.

Activins↗
PubMed2001

[Cytotoxicity of the strontium-substituted hydroxyapatite evaluated by MTT colorimetry].

This study was conducted to evaluate the cytotoxicity of strontium-substituted hydroxyapatite by methyl thiazolyl tetrazolium (MTT) colorimetry. We used the MTT method to assay the cytotoxicity of the strontium-substituted hydroxyapatite containing different strontium concentrations (1%, 5%, 10%, 100% Sr2+) and the pure hydroxyapatite. The results showed that the cytotoxicity scores of the different materials were grade 0 or grade 1. These led us to the conclusion that strontium-substituted hydroxyapatite has good biocompatibility.

Animals↗
PubMed2001

[Treatment of acute aplastic anemia with allogeneic peripheral blood stem cell transplantation: a case report and literature review].

OBJECTIVE: To report a patients with acute aplastic anemia(AAA) successfully treated with allogeneic peripheral blood stem cell transplantation(allo-PBSCT). METHODS: A 30 years old patient with AA received allo-PBSCT from a HLA-compatible sibling donor. PBSCs mobilization regimen was G-GSF 250 micrograms/d x 6. The conditioning regimen included (CTX 50 mg.kg-1.d-1) x 4 and (ATG 10 kg-1.d-01) x 2. 8.97 x 10(8) nucleated cells/kg, 9.20 x 10(6) CD34+ cells/kg, 11.20 x 10(5) CFU-GM/kg were transplanted. RESULTS: Hematopoietic reconstitution obtained on day 18 after allo-PBSCT. Monitoring of engraftment with three microsatellite markers showed mixed chimerism on day 18 and complete chimerism after day 25. No acute or chronic graft versus host disease (GVHD) occurred. In the follow-up duration of 240 days, the blood and bone marrow pictures were normal and the living status was good. CONCLUSION: Allo-PBSCT was an effective therapy in the treatment of acute aplastic anemia.

Acute Disease↗
PubMed2001

[Effects of activin and follistatin on FSH receptor mRNA expression of cultured Shao duck granulosa cells].

The aim of this study was to investigate the action of activin and follistatin either alone or in combination on FSH receptor mRNA expression. The results showed that activin alone increased FSH receptor mRNA level in the presence or absence of FSH in cultured granulosa cells, and the stimulating effect of activin on FSH receptor level was dose-dependent. This effect of activin was inhibited by FSP treatment which alone had no effect on FSH receptor expression. From the results, it can be concluded that activin and follistatin both exert autocrine actions on granulosa cells, and the two factors, possibly by regulating FSH receptor expression, may play important roles in follicular development.

Activins↗
PubMed2001

[Poison effect of plant granules on Oncomelania hupensis].

Plant granules (phi 2-3 mm) made of starch, gelatin and medicine plant powder were used to kill Oncomelania hupensis. The results showed that after eating the plant granules, the mortality of the snail was 92.5%-100% within 24 hrs. The poison effect of the plant granules was much better than that of others, e.g., they could kill snails 12-24 h earlier than Niclosamidum (1 x 10(-3) g.L-1). In a field experiment, the snail mortality was up to 61.5% by using plant granules.

Animals↗
PubMed2001

[Detection of GABAA alpha 2 mRNA in rat vestibular end organ with in-situ hybridization].

OBJECTIVE: To investigate the effect of the gamma-aminobutyric acid (GABA) on rat vestibular end organ. METHODS: In the rat inner ear paraffin slides, GABAA receptor alpha 2 subunit mRNA in vestibular end organ has been detected with in-situ hybridization. Digoxigenin-GABAA alpha 2 cDNA prob (549 base pair), Anti-Digoxigenin-AP (Fab fragments) and BM Purple AP Substrate (precipitating) have been used. RESULTS: GABAA receptor alpha 2 subunit mRNA has been found in all vestibular ganglion cells and nerve ending surrounding type I hair cells in rat's cristae ampullaris. GABAA alpha 2 has not been found in hair cells and supporting cells. As a positive control, GABAA alpha 2 mRNA has been found in Purkinje cells and granule cells in rat's cerebellum. GABAA alpha 2 has not been found in OMP negative control, non-prob negative control and non-anti-digoxingenin control in inner ear and cerebellum slides. CONCLUSIONS: GABAA alpha 2 receptor has been found in vestibular afferent nerve endings and vestibular ganglion cells. It strongly indicates that GABA is an afferent nerve transmitter in the vestibular end organ and plays an important role in the vestibular afferent nerve transmission.

Animals↗
PubMed2001

[Detection of mutations in exon 7 of p53 from fresh tumor samples by single-strand conformation polymorphism and direct DNA sequencing].

OBJECTIVE: To detect mutations of exon 7 of p53 gene in laryngeal squamous cell carcinoma (LSCC) and analyze the relationship between the mutation and LSCC. METHODS: Fresh tumor samples from 60 LSCC patients were examined using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and direct DNA sequencing. RESULTS: An extra band in SSCP 3 was shown in 25 out of 60 samples. Exon 7 of p53 were detected by direct DNA sequencing in 8 samples taken at random from 25 cases. In 8 cases, 1 base pair deletion CCC-->CC in 250 codon which may result in frame shift mutation was shown. Simultaneously, in 3 cases, transversion AGT-->GGG in 261 codon which may bring out missense mutation was found. In 2 cases, 1 base pair deletion CGG-->GG in 248 codon was detected. In another case, 1 base pair deletion AGG-->AG in 249 codon was detected. Transversion ATC-->TTC in 254 codon was found in one of the cases. Transversion GGT-->TCA in 262 codon was found in another case. CONCLUSION: The codon 248, 250, 261 may be "hot spots" in LSCC. Mutations and deletions in exon 7 of p53 gene occurred frequently in LSCC.

Adult↗
PubMed2000

Nine polymorphisms of angiotensinogen gene in the susceptibility to essential hypertension.

Even if the importance of angiotensinogen (AGT) gene has been known in gene targeting animals and humans genetic studies, its precise mechanism and the interaction among AGT gene variants, plasma AGT concentration and risk for hypertension remain uncertain. We examined whether AGT gene variants predispose to hypertension via an increase of plasma AGT concentration. Plasma AGT concentration was estimated from plasma angiotensin I which was cleaved by an excess amount of human renin and measured by RIA. Using 9 AGT gene variants which included new polymorphisms (G-152A and T+31C), we examined the association with hypertension and with plasma concentration by a case-control study. Haplotype analysis revealed that G-6A, T+31C and M235T polymorphisms were in absolute linkage disequilibrium and were associated with hypertension but not with plasma AGT level. On the other hand, -1074t;T235 haplotype was associated with an increase of AGT level but not with hypertension. In the haplotype analysis, only H3 haplotype frequency, which contained G-6, T+31 and M235 alleles, was significantly increased in normotensive subjects, suggesting that this haplotype is associated with a hypotensive effect. According to combined haplotype analysis of diallele and microsatellite markers, it remains a possibility that M235T, T+31C, G-6A, A-20C and G-1074T polymorphisms may play an important role in increased risk for essential hypertension. Our results suggest that the positive association between AGT polymorphism and hypertension is not simply explained by an increase of plasma AGT concentration.

Alleles↗
PubMed2000

Physiological control of smooth muscle-specific gene expression through regulated nuclear translocation of serum response factor.

Prolonged serum deprivation induces a structurally and functionally contractile phenotype in about 1/6 of cultured airway myocytes, which exhibit morphological elongation and accumulate abundant contractile apparatus-associated proteins. We tested the hypothesis that transcriptional activation of genes encoding these proteins accounts for their accumulation during this phenotypic transition by measuring the transcriptional activities of the murine SM22 and human smooth muscle myosin heavy chain promoters during transient transfection in subconfluent, serum fed or 7 day serum-deprived cultured canine tracheal smooth muscle cells. Contrary to our expectation, SM22 and smooth muscle myosin heavy chain promoter activities (but not viral murine sarcoma virus-long terminal repeat promoter activity) were decreased in long term serum-deprived myocytes by at least 8-fold. Because serum response factor (SRF) is a required transcriptional activator of these and other smooth muscle-specific promoters, we evaluated the expression and function of SRF in subconfluent and long term serum-deprived cells. Whole cell SRF mRNA and protein were maintained at high levels in serum-deprived myocytes, but SRF transcription-promoting activity, nuclear SRF binding to consensus CArG sequences, and nuclear SRF protein were reduced. Furthermore, immunocytochemistry revealed extranuclear redistribution of SRF in serum-deprived myocytes; nuclear localization of SRF was restored after serum refeeding. These results uncover a novel mechanism for physiological control of smooth muscle-specific gene expression through extranuclear redistribution of SRF and consequent down-regulation of its transcription-promoting activity.

Animals↗
PubMed2000

Canadian-American differences in the management of acute coronary syndromes in the GUSTO IIb trial: one-year follow-up of patients without ST-segment elevation. Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) II Investigators.

BACKGROUND: Little information exists concerning practice patterns between Canada and the United States in the management of myocardial infarction (MI) patients without ST-segment elevation and unstable angina. METHODS AND RESULTS: We examined the practice patterns and 1-year outcomes of 2250 US and 922 Canadian patients without ST-elevation acute coronary syndromes in the Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) IIb trial. The US hospitals more commonly had on-site facilities for angiography and revascularization. These procedures were performed more often and sooner in the United States than Canada, whereas Canadian patients were more likely to undergo noninvasive stress testing. The length of initial hospital stay was 1 day longer for Canadian than US patients. Recurrent and refractory ischemia was more common in Canada. One-year mortality was comparable between the 2 countries. However, at 6 months, even after baseline differences were accounted for, the (re)MI rate was significantly higher in Canadian than US patients with unstable angina (8.8% versus 5.8%, P:=0.039), as was the composite rate of death or (re)MI (13.1% versus 9.1%, P:=0.016). CONCLUSIONS: One-year mortality was comparable between Canada and the United States in both MI and unstable angina cohorts despite higher intervention rates in the United States. However, outcomes at 6 months among patients with unstable angina differed. Whereas more frequent coronary interventions were not associated with reduced recurrent MI or death among MI patients without ST elevation, they may favorably affect outcomes in patients with unstable angina.

Analysis of Variance↗
PubMed2000

Modulation of medical prefrontal cortical D1 receptors on the excitatory firing activity of nucleus accumbens neurons elicited by (-)-Stepholidine.

(-)-Stepholidine (SPD), with D1 agonistic action, elicited an excitatory firing activity of nucleus accumbens (NAc) neurons by intravenous administration, but this effect was hardly observed by iontophoresis of SPD into the NAc. The present study intends to determine whether D1 receptors in the medial prefrontal cortex (mPFC) are involved in the action of SPD on the firing activity of NAc neurons in the chloral hydrate-anesthetized male rats. The results showed that the intra-mPFC microinjected SCH-23390 (D1 antagonist, 30 mM), but not the D2 antagonist spiperone (30 mM), significantly attenuated the enhanced firing activity induced by intravenous injection of SPD (2 mg/kg). Similarly, the excitatory firing of NAc neurons was also exhibited by the microinjection of either SPD or D1 agonist SKF-38393 into the mPFC. The SPD-induced excitatory effect was in a dose-dependent way from 277.8 +/- 51.3% (10 mM) to 1105.4 +/- 283.5% (30 mM) of NAc basal firing, which was completely reversed by SCH-23390 (i.v.). Furthermore, the direct D1 agonistic action of SPD on the mPFC neuron was observed with microiontophoresis. These results indicate that SPD possesses a direct agonistic action on the mPFC D1 receptors, by which it modulates the firing activity of NAc neurons.

Animals↗
PubMed2000

Cellular immune response of lymph nodes from dogs following the intradermal injection of a recombinant antigen corresponding to a 66 kDa protein of Echinococcus granulosus.

A recombinant polypeptide (referred to as EgA31), which represents a 66kDa protein, was prepared from an Echinococcus granulosus cDNA library. In order to assess its potential to induce cellular immune responses, dog popliteal and prescapular lymph nodes were sensitized with this recombinant polypeptide. Subpopulations of lymphocytes were then analyzed by flow cytometry and immunohistochemistry on lymph node sections. Five days after the sensitization, the paracortical areas of the lymph nodes appeared hypertrophic, the number of CD3+, CD4+, CD8+ and CD5+ cells increased, the number of B-cells began to augment and some secondary follicles occurred, and a number of CD4+ cells appeared in germinal centers. Many large secondary follicles and a significantly augmented number of CD5+ cells in cords of medullae were observed 10 days after the sensitization. These active cellular responses strengthen the interest for further studies on the development of a vaccine with this recombinant polypeptide.

Animals↗
PubMed2000

Distinct roles of the NH2- and COOH-terminal domains of the protein inhibitor of activated signal transducer and activator of transcription (STAT) 1 (PIAS1) in cytokine-induced PIAS1-Stat1 interaction.

STATs are activated by tyrosine phosphorylation on cytokine stimulation. A tyrosine-phosphorylated STAT forms a functional dimer through reciprocal Src homology 2 domain (SH2)-phosphotyrosyl peptide interactions. IFN treatment induces the association of PIAS1 and Stat1, which results in the inhibition of Stat1-mediated gene activation. The molecular basis of the cytokine-dependent PIAS1-Stat1 interaction has not been understood. We report here that a region near the COOH terminus of PIAS1 (amino acids 392-541) directly interacts with the NH(2)-terminal domain of Stat1 (amino acids 1-191). A mutant PIAS1 lacking the Stat1-interacting domain failed to inhibit Stat1-mediated gene activation. By using a modified yeast two-hybrid assay, we demonstrated that PIAS1 specifically interacts with the Stat1 dimer, but not tyrosine-phosphorylated or -unphosphorylated Stat1 monomer. In addition, whereas the NH(2)-terminal region of PIAS1 does not interact with Stat1, it serves as a modulatory domain by preventing the interaction of the COOH-terminal domain of PIAS1 with the Stat1 monomer. Thus, the cytokine-induced PIAS1-Stat1 interaction is mediated through the specific recognition of the dimeric form of Stat1 by PIAS1.

Binding Sites↗