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Y Guo

Publications and source records attributed to Y Guo.

At least 109 records · Page 6Linked to original sources
PubMed2001

[Research on the selecting suspension cell line of higher productivity of flavonol glycoside by hypoxia stress as well as the stability in subcultures].

Investigate the influence of culture media to growth and flavonol glycoside synthesis of calli introduced from seedling of Ginkgo biloba. 6 cell lines were selected from calli by hypoxia stress. Among these cell lines the best one TZ-1 which growth index was 4.12 and the flavonol glycoside content was 1.25% in dried cell which was enhanced 257.1% compared with callus. The stability in subcultures was investigated: The average content of flavonol glycoside was 1.25% in dried cells and the growth index was 3.99 during 6 subcultures. Which variation coefficient was separately 0.065 and 0.048. The results show that hypoxia stress is a efficient method to select suspension cell line of higher productivity of flavonol glycoside.

Cell Hypoxia↗
PubMed2001

[Analysis on genetic polymorphism of 13 STR loci on chromosomes 11 and 19 in Chinese Hans].

OBJECTIVE: To analyze the genetic polymorphism of 8 STR loci on chromosome 11 and 5 STR loci on chromosome 19 in Chinese Hans. METHODS: Polymerase chain reaction-single strand length polymorphism(PCR-SSLP) was used to genotype 100 randomly selected individuals of the Han nationality at 8 STR loci(D11S1984, D11S1999, D11S1392, D11S1985, D11S2002, D11S1986, D11S4464 and D11S2359) on chromosome 11 and 5 STR loci(D19S247, D19S714, D19S433, D19S246, D19S254) on chromosome 19. RESULTS: Eight alleles and 26 genotypes, 9 alleles and 15 genotypes, 6 alleles and 16 genotypes, 12 alleles and 40 genotypes, 6 alleles and 19 genotypes, 12 alleles and 48 genotypes, 8 alleles and 20 genotypes, 7 alleles and 13 genotypes were observed at D11S1984, D11S1999, D11S1392, D11S1985, D11S2002, D11S1986, D11S4464 and D11S2359. The heterozygosities for the 8 STR loci were 87%, 68%, 73%, 92%, 71%, 86%, 75% and 71%, respectively. Ten alleles and 19 genotypes, 10 alleles and 26 genotypes, 10 alleles and 24 genotypes, 11 alleles and 29 genotypes, 8 alleles and 18 genotypes were observed at D19S247, D19S714, D19S433, D19S246, D19S254. The heterozygosities for the 5 STR loci were 63%, 82% 72%, 81% 74%, respectively. CONCLUSION: The distribution of allele frequencies of 8 STR loci on chromosome 11 and 5 STR loci on chromosome 19 was consistent with the Hardy-Weinberg equilibrium and the highly genetic polymorphism was observed in Chinese Han population.

China↗
PubMed2001

[Cytogenetic analysis on 1058 cases of acute nonlymphocytic leukemia].

OBJECTIVE: To evaluate the karyotypic status in a large series of acute nonlymphocytic leukemia(ANLL) cases. METHODS: A total of 1058 cases of de novo ANLL were studied. Chromosome preparations were made on bone marrow cells using direct method and short-term culture. Karyotypes were analyzed by R-banding in all cases and G-banding in some cases in addition. RESULTS: Six hundred and thirty cases (60%) had clonal chromosomal abnormalities. 25 categories of major karyotypic abnormalities were found. Among them, 11 were the specific chromosomal rearrangements seen in 481 cases, accounting for 76% of the total number of patients with karyotypic abnormalities. Isolate trisomy 8 (21 cases) was the most common numerical abnormality. t(15;17)(211 cases) and t(8;21)(200 cases) were the most frequent structural abnormalities. The 1.1% of M(2), 72% of M(3), 71% of M(4E0), 50% of M(2), 6 % of M(5) and 1.4% of M(2) had t(7;11), t(15;17), inv(16), t(8;21), t/del(11q 23) and t/del(12p) abnormalities, however, the 100% of t(7;11), 100% of t(15;17 ), 100% of inv(16), 88.5% of t(8;21), 83% of t/del(11q23) and 62% of t/del(12p) were detected in patients with M(2), M(3), M(4E0), M(2), M(5) and M(2) subtypes, respectively. CONCLUSION: By conventional banding technique, including R- and G-bandings, 60% of patients with ANLL may be found to have clonal chromosomal abnormalities which are predominantly specific chromosomal rearrangements correlated with specific FAB subtypes. Thus, karyotype is an important indicator for diagnosis and classification of ANLL.

Adolescent↗
PubMed2001

[Detection of monosomy 7 or 7q- in cases of myelodysplastic syndrome].

OBJECTIVE: To investigate the value of interphase fluorescence in situ hybridization(FISH) in the detection of monosomy 7 (-7)or deletion of long arm of chromosome 7(7q-) in the cases of myelodysplastic syndrome (MDS). METHODS: Forty-six cases of MDS and 10 normal controls were studied simultaneously by conventional karyotype analysis and interphase FISH technique using SpectrumRed directly labeled DNA specific probe for 7q32. Two hundred interphase cells were analyzed for each case and the cells with one red hybridization spot<7% were regarded as positive. RESULTS: Three cases displayed -7/7q- by conventional cytogenetics(CC) and were confirmed by interphase FISH. Six cases in 43 cases who did not show -7/7q- by CC displayed -7/7q- by interphase FISH. CONCLUSION: Interphase FISH is very useful for the detection of -7 or 7q- in MDS and it is more sensitive than CC.

Adolescent↗
PubMed2001

[No evidence for association between the alpha 2-macroglobulin polymorphism and Alzheimer's disease in the Han Chinese].

OBJECTIVE: To determine the effect of the pentanucleotide deletion polymorphism adjacent to a consensus splice site in intron 17 of alpha 2-macroglobulin(A2M) gene on the development of late-onset Alzheimer's disease (LOAD) in the Han Chinese in Guangzhou area. METHODS: A2M and apolipoprotein E genotypes were examined by polymerase chain reaction(PCR) and restriction fragment length polymorphism (RFLP) techniques in the patients(32 men and 65 women) with LOAD and age-matched healthy elderly Chinese subjects (57 men and 54 women). RESULTS: The A2M gene deletion allele frequency was 2.6% in the cases with LOAD and 2.7% in the controls. In the LOAD cases, the frequency of apoE-epsilon4 increased significantly (Z=3.32, P<0.01). ApoE-epsilon4 was associated with LOAD (RR=2.67, chi(2)=10.71, P<0.01) while the A2M deletion polymorphism was not associated with LOAD even the samples were stratified according to the presence of the apoE-epsilon4 allele. CONCLUSION: The above data demonstrate that there is no evidence for the association of A2M polymorphism with the development of LOAD in the Han Chinese population in Gaungzhou.

Alzheimer Disease↗
PubMed2001

Clinical study on treatment of chronic renal failure with shenshuailing.

The therapeutic effects of Shenshuailing Kou Fu Ye (SKFY [symbol: see text], the Oral Liquid for Renal Failure) and Shenshuailing Guan Chang Ye (SGCY [symbol: see text], the Enema for Renal Failure) were evaluated in treatment of chronic renal failure, with coateg aldehyde oxystarch as the controls. The changes in the clinical symptoms, serum creatinine, blood urea nitrogen and creatinine clearance rate were observed. The total effective rate in the former was 90.46%, and the latter 60.43%.

Aged↗
PubMed2001

[Therapeutic potential of recombinant adenovirus expressing p53 in hepatocellular carcinoma cell lines].

OBJECTIVE: To investigate the effects of the recombinant adenoviral vector Ad-p53 on the biological behavior of hepatocellular carcinoma (HCC) cells in vitro and in vivo. METHODS: With recombinant adenoviral vector expressing WT-p53 (Ad-p53), p53 gene was transfected into the HCC cell line, PLC/PRF/5. The cytotoxicities of Ad-p53 to cells were measured by MTT assay. Cell growth properties and cell cycle patterns were assessed with flow cytometry. The animal model was developed by injecting HCC cells into the dorsum of nude mice. Ad-p53 was injected intratumorally. The animals were killed, and then excised tumors were weighed and analyzed for p53 and p21 protein expression using western blot assay. RESULTS: The introduction of exogenous wild-type p53 resulted in the inhibition of cell growth, high G2/M ratio and cell apoptosis, and low S ratio in PLC/PRF/5. The expression of both p53 and p21 proteins was upregulated in the cells. CONCLUSIONS: Replication-deficient adenoviral vector expressing WT-p53 may be useful for gene therapy of HCC.

Adenoviridae↗
PubMed2001

Xe991 reveals differences in K(+) channels regulating chloride secretion in murine airway and colonic epithelium.

The cognitive enhancer XE991 interacts with K(+) channels consisting of KCNQ2 and KCNQ3 heteromultimers to block the M-current. XE991 can also block KCNQ1 K(+) channels expressed in oocytes, but sensitivity is reduced when the channels are coexpressed with minK (KCNE1). The purpose of the study was to examine the interaction of XE991 with other types of K(+) channel, especially those in the basolateral membranes of murine epithelia. K(+) channel blockade was measured by the inhibition of chloride secretion resulting from depolarization. XE991 inhibited the chloride secretory current in colonic epithelia by an interaction with basolateral K(+) channels when forskolin was used as the stimulus. However, when 1-ethyl-2-benzimidazolinone (EBIO) was used to stimulate chloride secretion, XE991 was ineffective unless charybdotoxin was also present. Because EBIO also activates Ca(2+)-sensitive K(+) channels, whereas forskolin activates only cAMP-sensitive K(+) channels, it is concluded that the latter are the targets for XE991. XE991 had effects similar to those of 293B on epithelial chloride transport, for which the target is known to be KCNQ1/KCNE3 multimers. mRNA for both these components of the cAMP-sensitive K(+) channels were found in high abundance in the colon, whereas KCNE1 was barely detectable. Furthermore, both XE991 and 293B were active in colonic epithelia from KCNE1 knockout mice. By contrast, in nasal epithelium, the forskolin sensitive chloride secretory current was barely sensitive to XE991 but was sensitive to clofilium. Xenopus laevis oocytes in which both KCNQ1 and KCNE3 had been expressed were significantly more sensitive to XE991 than oocytes expressing only KCNQ1.

Animals↗
PubMed2001

[Preparation and identification of activity of antiplatelet-derived growth factor receptor beta subunit hammerhead ribozyme in vitro].

OBJECTIVE: To study the preparation and cleavage activity of ribozyme directed against platelet-derived growth factor (PDGF) receptor beta subunit gene transcript in vitro. METHODS: PDGF receptor B subunit gene fragments were cloned into T-vector under the control of T7 promotor. 32P-labeled PDGF receptor beta subunit transcripts as target-RNAs were transcribed in vitro and purified by PAGE. Ribozyme gene designed by computer targeting the extracellular domain was cloned into vector P1.5 between 5'-cis ribozyme and 3'-cis ribozyme. 32P-labeled ribozyme transcripts was gel-purified, incubated with target-RNAs at different conditions and autoradiographed after denaturing gel-electrophoresis. RESULTS: The preparation of ribozyme was correct. It was active at 37 degrees C. The optimal temperature was 50 degrees C, Km=13,20 nm, Kcat=0.28 min-1. The cleavage efficiency was up to 78.3%. CONCLUSIONS: Ribozyme prepared in vitro possesses specific catalytic activity.

Animals↗
PubMed2001

[Preliminary clinical study on the management of angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens implantation].

OBJECTIVE: To investigate the clinical results of phacoemulsification with foldable posterior chamber intraocular lens (PC-IOL) implantation in the management of angle-closure glaucoma with cataract. METHODS: Phacoemulsification with PC-IOL implantation performed on 47 eyes (42 cases) with angle-closure glaucoma and cataract was retrospectively studied, including 26 eyes with primary acute angle-closure glaucoma, 12 eyes with primary chronic angle-closure glaucoma, 5 eyes with secondary acute angle-closure glaucoma and 4 eyes with secondary chronic angle-closure glaucoma. RESULTS: After a mean postoperative follow-up of (18.40 +/- 9.51) months, the intraocular pressure was reduced from a preoperative mean of (25.47 +/- 18.43) mm Hg to a postoperative mean of (11.99 +/- 4.48) mm Hg (t = 4.918, P < 0.001). The mean anterior chamber depth was (1.69 +/- 0.46) mm preoperatively and (2.28 +/- 0.36) mm postoperatively (t = 7.738, P < 0.001). The best-corrected visual acuity was improved in 41 of 47 eyes (87.2%). CONCLUSION: Phacoemulsification with posterior chamber foldable intraocular lens implantation can be a good alternative in treating angle-closure glaucoma with cataract.

Adult↗
PubMed2001

Characterization of hemagglutinin gene of influenza A virus subtype H9N2.

OBJECTIVE: To determine the origin of human influenza A (H9N2) virus and the relationship among H9N2 strains isolated from different hosts, on the basis of molecular biology. METHODS: Viruses were passed in embryonated hen eggs, and virion RNA was extracted from allantoic fluid and reverse transcribed to synthesize cDNA. cDNA was amplified by PCR and the PCR product was purified with a purification kit. Afterwards RNA sequence analysis was performed by dideoxynucleotide chain termination and a cloning method. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign (version 1.03) and Editseg (version 3.69) softwares. RESULTS: The amino acid sequences at the cleavage site between HA1 and HA2 domains of H9N2 viruses isolated in China are R-S-S-R. One pigeon strain contains seven potential glycosylation sites on the HA protein molecule, while all others have eight. There are 2 to 15 differences of amino acid sequences distributed at 24 different positions on the HA protein molecules among six H9N2 viruses. The H9N2 viruses with multiple lineages of HA genes were co-circulating in China recently. CONCLUSION: The highest possibility is that human influenza A (H9N2) virus was derived from Chicken H9N2 virus, and not derived from pigeon H9N2 virus. However, it is still unknown whether the H9N2 virus could transmit from person to person. The H9N2 viruses with multiple lineages of HA genes are co-circulating in China.

Amino Acid Sequence↗
PubMed2001

Expression of beta-catenin in renal cell carcinoma.

OBJECTIVE: To investigate the expression of beta-catenin and its mRNA in renal cell carcinoma. METHODS: Twenty-six cases with renal cell carcinoma (RCC) were studied by immunohistochemistry, Western blot and RT-PCR. RESULTS: We found the expression of beta-catenis is higher in cancer tissues than in normal kidney tissues and the level of beta-catenin is associated with the tumor stage. Its expression in tumor of pT3 and pT4 is obviously higher than pT1 and pT2 (P < 0.01). That is to say, there was an overexpression of beta-catenin protein in RCC and its level was related to the tumor stage, but the expression of beta-catenin mRNA had no difference between tumor tissue and normal tissue. CONCLUSION: beta-catenin may be related to the occurrence and progress of RCC.

Adult↗
PubMed2001

Sodium channels in the apical membrane of human nasal epithelial cells.

OBJECTIVE: To study the electrophysiological properties of sodium channels in the apical membrane of human nasal epithelial cells. METHOD: Nasal epithelial cells of human inferior turbinate from patients with obstructive sleep apnea syndrome were cultured in serum free medium on collagen gel-coated membranes at an air-liquid interface and studied by a patch clamp technique. RESULTS: In cell-attached patches, a typical single channel current with a conductance of 21.09 pS and reversal potential of -50.96 were recorded. The permeability ratio PNa/PK was more than 5.80. In the presence of 10(-4) mmol/L amiloride in the pipette, the incidence of sodium channels decreased from 26.67% to 5.13%. This revealed that a population of channels were inhibited by amiloride at a dose of 10(-4) mmol/L. Ca2+ at dose of 10(-3) mmol/L did not influence the incidence of sodium channels. There was no obvious association between voltage and the open probability of the channels. CONCLUSIONS: Our results indicate that most Na+ channels in cell-attached patches of human nasal epithelial cells are amiloride-sensitive and Na+ selective. Only a few channels are amiloride-insensitive. The channels were not activated by extracellular Ca2+ and the open probability followed a voltage-independent manner.

Amiloride↗
PubMed2001

Suppression subtractive hybridization for identifying differentially expressed genes in renal cell carcinoma.

OBJECTIVE: To construct a renal cell carcinoma (RCC) cDNA subtractive library using suppression subtractive hybridization. METHODS: Polyadenylated RNA [Poly (A)+ RNA] was isolated from tissues of RCC and normal kidney, and single-strand cDNAs and double-strand cDNAs were synthesized in turn. RCC cDNAs were divided into two groups and ligated to the specific adaptors I and 2, and then hybridized with normal kidney cDNA twice with two rounds of suppression PCR. Second round PCR products were cloned to T/A plasmid vectors to set up the subtractive library. One hundred clones were randomly picked to perform enzyme digest analysis, and some underwent sequence analysis and Northern blot to identify RCC specifically expressed genes. SMART RACE procedure was operated to clone full length novel RCC specifically expressed genes. RESULTS: A human RCC subtractive library with high subtractive efficiency was successfully set up. The amplified library contains 350 positive clones. Random analysis of 100 clones with enzyme restriction showed that 85 plasmids in the clones contained 50-400 bp inserts. Sequence analysis was performed for 10 clones. All the 10 sequences were unknown before and derived from 6 unique, novel genes among which the cDNA insert RCC18 had five copies. Northern blot analysis showed that RCC18 cDNA was highly expressed in RCC, but no signal could be detected in normal kidney. Using SMART RACE technique, we obtained the full length of the novel gene RCC18. CONCLUSIONS: The constructed cDNA subtractive library of human RCC is a highly efficient one and lays a solid foundation for large scale screening and cloning new and specific oncogenes or tumor suppressor genes of RCC. The novel specifically expressed genes provided an important clue for studying the mechanisms of occurrence and development of RCC.

Carcinoma, Renal Cell↗
PubMed2001

Regulation of osteopontin expression in a rat model of urolithiasis.

OBJECTIVE: To investigate the relationship between the expression and regulation of osteopontin (OPN) and urolithiasis. METHODS: Normal and stone model rats were treated with 1,25-dihydroxyvitamin D3(D3), vitamin K, testosterone or estradiol for 7 days, and the expression of osteopontin and its mRNA were detected with immunohistochemistry and Northern blot, respectively. Crystals deposited in rat kidneys were observed with a polarization microscope. The concentrations of crystal components in rat urine were determined. RESULTS: The results showed that vitamin K, testosterone and estradiol up-regulated the expression of OPN mRNA and its protein, thus decreasing the precipitation of calcium oxalate in rat kidneys. D3 increased the concentration of calcium in urine, and accelerated the sedimentation of calcium oxalate in rat kidneys. CONCLUSIONS: These findings indicate that OPN may be an important macromolecule in the normal endogenous inhibition of the formation of urolithiasis. Vitamin K, testosterone and estradiol inhibit the formation of stones via up-regulating the expression of OPN in kidneys, while D3 over dose may accelerate the process.

Animals↗
PubMed2001

[Study of loss of heterozygosity at chromosome 11q13 in nasopharyngeal carcinoma].

OBJECTIVE: To analyze the loss of heterozygosity (LOH) from STS sites at 11q13 in nasopharyngeal carcinoma(NPC). METHODS: Relatively pure tumor tissues were obtained by microdissetion. PCR was used to perform microsatellite analysis of NPC samples using D11S4946, PYGM, D11S449 and INT-2 as primers, which span the MEN-1 gene. RESULTS: Thirty-six of 38 cases studied showed LOH in at least one of the loci analyzed. Among the primers used, D11S4946 had the highest frequency of LOH, (78.8%). The LOH frequency was 51.5% for INT-2, 45.5% for PYGM and 45.7% for D11S449, respectively. CONCLUSION: The high frequency of loss of heterozygosity at 11q13 in NPC implies that there may be some tumor suppressor gene(s) involved in NPC tumorigenesis.

Chromosomes, Human, Pair 11↗