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Ying Chen

Publications and source records attributed to Ying Chen.

At least 253 records · Page 14Linked to original sources
PubMed2003

The nicotinic alpha 4 beta 2 receptor selective agonist, TC-2559, increases dopamine neuronal activity in the ventral tegmental area of rat midbrain slices.

The ability of alpha4beta2 nicotinic acetylcholine receptors to modulate dopaminergic (DA) cell activity in the ventral tegmental area (VTA) in rat midbrain slices was assessed using a selective alpha4beta2 receptor agonist, TC-2559 ((E)-N-methyl-4-[3-(5-ethoxypyridin)y1]-3-buten-1-amine). The selectivity of TC-2559 was characterized across 6 recombinant human nicotinic receptors (alpha4beta2, alpha2beta4, alpha4beta4, alpha3beta4, alpha3beta2 and alpha7) stably expressed in mammalian cell lines. Using a fluorescent imaging plate reader and fluo-3 to monitor changes in intracellular calcium, TC-2559 was found to be at least 69 fold more potent on alpha4beta2 than on other heteromeric subtypes, with an efficacy of 33%. No activity on the homomeric alpha7 subtype was detected. TC-2559 also showed selectivity for alpha4beta2 over the alpha4beta4 and alpha7 subtypes expressed in Xenopus oocytes. When bath applied to VTA slices, TC-2559 increased the firing of DA cells in a dose-dependent manner, in the same concentration range that activates alpha4beta2 receptors in recombinant cell lines or oocytes. The effect of TC-2559 was blocked by 2 microM dihydro-beta-erythroidine (an alpha4beta2-preferring antagonist), but not by 10 nM methyllycaconitine (an alpha7 antagonist). Glutamate receptor antagonists (6-cyano-7-nitroquinoxaline-2,3-dione and D(-)-2-amino-5-phosphonopentanoic acid) did not reduce TC-2559-induced responses, suggesting that the increase in DA cell firing induced by TC-2559 is caused by direct postsynaptic depolarisation via the activation of alpha4beta2 receptors and not by enhancement of glutamate release.

Action Potentials↗
PubMed2003

Correlation between stinging, TEWL and capacitance.

BACKGROUND/AIMS: To study the correlation between stinging and skin barrier and to make the lactic acid stinging test much safer. METHODS: The modified lactic acid stinging test with 3% and/or 5% aqueous solution of lactic acid combined with transepidermal water loss (TEWL) and capacitance (CAP) was used. The amount of 50 microL-test material was applied on test areas, the skin of both sides nasolabial fold of 50 healthy subjects. Subjects assessed stinging basing on a 4-point scale at 0, 2.5, 5.0 and 8 min TEWL and CAP were measured at baseline and 8 min. RESULTS: The results show that the tendency of decrease in baseline CAP and increase in baseline TEWL are proportional with the increase of the sum of clinical scores (CSS). In 5% lactic acid test, negative correlation between changing ratio of TEWL (PTEWL) and clinical score at 5 min (CS5 min), and negative correlation between changing ratio of capacitance (PCAP) and CS5 min are registered. CONCLUSION: Our data indicate that there is certain relationship between the degree of stinging and the skin barrier. The stinging test method modified by lower concentration aqueous lactic acid and the assessment combined with PTEWL and PCAP is suitable for Chinese to evaluate the skin susceptibility.

Administration, Topical↗
PubMed2003

Embryonic stem cells generated by nuclear transfer of human somatic nuclei into rabbit oocytes.

To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the transfer of human somatic nuclei into rabbit oocytes. The number of blastocysts that developed from the fused nuclear transfer was comparable among nuclear donors at ages of 5, 42, 52 and 60 years, and nuclear transfer (NT) embryonic stem cells (ntES cells) were subsequently derived from each of the four age groups. These results suggest that human somatic nuclei can form ntES cells independent of the age of the donor. The derived ntES cells are human based on karyotype, isogenicity, in situ hybridization, PCR and immunocytochemistry with probes that distinguish between the various species. The ntES cells maintain the capability of sustained growth in an undifferentiated state, and form embryoid bodies, which, on further induction, give rise to cell types such as neuron and muscle, as well as mixed cell populations that express markers representative of all three germ layers. Thus, ntES cells derived from human somatic cells by NT to rabbit eggs retain phenotypes similar to those of conventional human ES cells, including the ability to undergo multilineage cellular differentiation.

Adult↗
PubMed2003

Single nucleotide polymorphisms of the human cyp2a13 gene: evidence for a null allele.

Human CYP2A13 is believed to be important in the metabolic activation of tobacco-specific nitrosamines in the respiratory tract; therefore, genetic polymorphisms of the CYP2A13 gene may be associated with interindividual differences in the risks of tobacco-related tumorigenesis. Our earlier studies identified a frequent single nucleotide polymorphism in CYP2A13 exon 5, Arg257Cys, which led to an approximate 50% decrease in metabolic activities. In the present study, three additional coding region mutations (Arg25Gln, Arg101Stop, and Asp158Glu) and several mutations in the introns and flanking regions were identified in a Chinese patient population. Of particular interest is the Arg101Stop mutation, which was due to a C > T change in exon 2. Thus, individuals homozygous for this nonsense mutation would not have a functional CYP2A13 protein and, therefore, might have reduced sensitivity to xenobiotic toxicity resulting from CYP2A13-mediated metabolic activation in the respiratory tract. The frequencies of the coding region mutations were further examined using random samples of white, black, Hispanic, and Asian newborns from New York. The frequency of the Arg25Gln mutation in Asian newborns (9.6%) was very similar to that found in the Chinese population (10.9%). On the other hand, the Arg101Stop mutation was not detected in 136 newborn samples examined (23 white, 21 black, 19 Hispanic, and 73 Asian), suggesting that this mutation may be unique for the Chinese patient population. Haplotype analysis indicated that the Arg25Gln and Arg257Cys mutations are parts of a common haplotype. However, an additional haplotype that consists of the 25Gln but not the 257Cys allele was also identified.

Alleles↗
PubMed2003

Small interfering RNA suppression of polyamine analog-induced spermidine/spermine n1-acetyltransferase.

N1,N11-diethylnorspermine (DENSPM) is a polyamine analog that down-regulates polyamine biosynthesis and potently upregulates the polyamine catabolic enzyme spermidine/spermine N1-acetyltransferase (SSAT). In certain cells, such as SKMEL-28 human melanoma cells, induction of SSAT is associated with rapid apoptosis. In this study, we used small interfering RNA (siRNA) to examine the role of SSAT induction in mediating polyamine pool depletion and apoptosis. siRNA duplexes were designed to target three independent sites in the SSAT mRNA coding region (siSSAT). When transfected under nontoxic conditions, two of the duplexes selectively reduced basal SSAT mRNA in HEK-293 cells by >80% and prevented DENSPM-induced SSAT mRNA by 95% in SK-MEL-28 cells. Treatment of SK-MEL-28 cells with 10 muM DENSPM in the presence of 83 nM siSSAT selectively prevented the 1400-fold induction of SSAT activity by approximately 90% and, in turn, prevented analog depletion of spermine (Spm) pools by approximately 35%. siSSAT also prevented DENSPM-induced cytochrome c release and caspase-3 cleavage at 36 h and apoptosis at 48 h as measured by annexin V staining. Overall, the data directly link analog induction of SSAT to Spm pool depletion and to caspase-dependent apoptosis in DENSPM-treated SK-MEL-28 cells. This represents the first use of siRNA technology directed toward a polyamine gene and the first unequivocal demonstration that SSAT induction initiates events leading to polyamine analog-induced apoptosis.

Acetyltransferases↗
PubMed2003

When should a trial of fluoxetine for major depression be declared failed?

OBJECTIVE: Although the newer antidepressants are widely used, little is known about how long it takes to see their full effect. The authors sought to determine how many weeks a fluoxetine trial with no improvement should continue before treatment is changed. METHOD: The data involved 840 patients in a 12-week open trial of fluoxetine, 20 mg/day, followed by a blinded, placebo-controlled discontinuation study. Outcomes at 4, 6, 8, 10, and 12 weeks were classified as nonresponse, partial response, response, and remission and were based on Hamilton Depression Rating Scale scores. The rate of remission at week 12 was calculated for each group of patients without remission at the earlier time points. The time to relapse during weeks 13-26 of the discontinuation study was examined in patients taking placebo and fluoxetine in relation to status at week 6. RESULTS: Patients unimproved at week 6 had a remission rate at week 12 of 31%-41%. For patients with remission at week 12, level of improvement at week 6 did not affect prognosis in weeks 13-26. Of the unimproved patients at week 8, 23% had remissions by week 12. The week 12 remission rate for unimproved patients at week 4 was clearly high enough to justify continued treatment; the rate for unimproved patients at week 10 was too low. CONCLUSIONS: These data suggest that nonresponse to fluoxetine should not be declared until 8 weeks of treatment have elapsed. Practitioners should discuss trial length with patients at the beginning of treatment.

Adolescent↗
PubMed2003

[Morphological observation of mesenchymal stem cells cultured with allogenic decalcified bone matrix].

OBJECTIVE: To investigate the feasibility of using decalcified bone matrix loaded with mesenchymal stem cells (MSCs) derived from adult human bone marrow as scaffolds for bone tissue engineering. METHODS: Allogenic decalcified bone matrix was prepared. MSCs were isolated from adult human bone marrow with monocyte-separating medium and then cultured in basic medium of mesenchymal stem cells (MSC). The third generation of the cultured cells were identified by FITC-antiCD105, seeded onto allogenic decalcified bone matrix followed by observation under scanning electron microscope and invert microscope a week later. RESULTS: Rapid proliferation of both primary and subcultured MSCs was observed, and CD105-positive cells reached 64.1% among the third generation of the cells. MSCs also grew well and proliferated rapidly after being cultured with decalcified bone matrix. CONCLUSION: Naive MSCs are ideal seeding cells for bone tissue engineering, and the allogenic decalcified bone matrix loaded with MSCs may be used as a good scaffold.

Bone Matrix↗
PubMed2003

[Expression of PTEN-encoding product in different stages of carcinogenesis and progression of gastric carcinoma].

OBJECTIVE: To illustrate the significance of expression of phosphatase and tensin homologue derived from chromosome ten (PTEN) encoding product in normal mucosa, intestinal metaplasia (IM), dysplasia and carcinoma of the stomach, and to evaluate its clinical implication in tumorigenesis and progression of gastric carcinoma. METHODS: Formalin-fixed and paraffin-embedded tissues from 184 cases of gastric carcinoma, its adjacent normal mucosa, IM and dysplasia were evaluated for the expression of PTEN by SABC immunohistochemistry. PTEN expression was assessed as to tumor stage, lymph node metastasis, Lauren's classification and WHO histological classification of gastric carcinoma. Expression of VEGF protein was also studied in 60 cases of gastric carcinoma, with its correlation with PTEN concerned. RESULTS: The positive rates of PTEN protein were 100% (102/102), 98.5% (65/66), 66.7% (4/6) and 47.8% (88/184) in normal mucosa, IM, dysplasia and carcinoma of stomach, respectively. The positive rates in the last two groups were lower than the first two (P < 0.01). PTEN was less expressed in advanced gastric carcinoma than in early ones (42.9% vs 67.6%, P < 0.01). The positive rate of PTEN protein was lower in gastric carcinoma with lymph node metastasis than without (40.3% vs 63.3%, P < 0.01). PTEN was less expressed in diffuse-type gastric carcinoma than in intestinal-type (41.5% vs 57.8%, P < 0.05). Signet ring cell carcinoma expressed PTEN stood the lowest (25.0%, 7/28), which was less than well and moderately differentiated ones (61.8%, 21/34) (P < 0.01). Expression of PTEN was inversely correlated with expression of VEGF though without any significance (P > 0.05). CONCLUSION: Loss or reduced expression of PTEN protein is common in carcinogenesis and progression of gastric cancer. Altered expression of PTEN may contribute to carcinogenesis and progression of gastric cancer by increasing angiogenesis, cellular adhesion and mobility and so on. PTEN may be an objective marker for pathologically biological behavior of gastric carcinoma.

Adult↗
PubMed2003

[Study on the clinical use of alpha-fetoprotein (AFP) colloidal gold diagnostic strip].

OBJECTIVE: To test the sensitivity and specificity of alpha-fetoprotein (AFP) colloidal gold diagnostic strip as compared with RIA-AFP diagnostic kit. METHODS: Double blind method was used to test sera from 426 healthy people and 1567 patients selected in two general hospitals and a cancer hospital. Each serum was measured by RIA-AFP and AFP colloidal gold diagnostic strip on the same day. RIA-AFP diagnostic results was identified as true positive or negative. RESULTS: Among 426 healthy people, all the RIA-AFP test showed negative result (serum AFP concentration less than 25 IU/ml), but the AFP colloidal gold diagnostic strip had 1.88% false positive. When comparing the result from 1567 patients measured by RIA-AFP, the sensitivity and specificity of AFP colloidal gold diagnostic strip were 99.3%, and 97.2%, respectively. The crude correspondence rate between the two diagnostic regents was 97.6%. CONCLUSION: AFP colloidal gold diagnostic strip showed very good result and could be used as a screening diagnostic kit in clinic and hospital settings.

Biomarkers, Tumor↗
PubMed2003

[Prognostic significance of lymph node micrometastasis in colorectal cancer].

BACKGROUND & OBJECTIVE: There have been many controversies about the prognostic significance of lymph node micrometastasis. The aim of this study was to characterize the prognostic significance of lymph node micrometastasis of colorectal cancer. METHODS: Specimens of curative resection between 1988 and 2001 were collected from The Affiliated Hospital of Jianghan University Medical and Life Science College. All 80 patients (30 cases of rectal cancer, 50 cases of colon cancer) had complete examination data. A total of 3869 lymph nodes (48.36 per case) were found by clearing fat method. The interrupted serial 4-micron sections, routine hematoxylin and eosin staining and immunohistochemistry methods were used to detect the lymph node metastasis and micrometastasis (small tumor cells cluster diameter <or=0.2 mm or tumor cells detected in the lymph nodes <or=50). All data was processed using Cox univariate analysis and Spearman rank correlation analysis (SAS 8.1 software). RESULTS: Metastases were found in 232 (6%) lymph nodes examined and micrometastases in 39 (1.01%) lymph nodes. In the cases of rectal cancer, a highly significant correlation was found between lymph node metastases and mortality by univariate analysis (Chi(2)=9.94, P=0.0016) and micrometastases by Spearman rank correlation analysis (r=0.44, P=0.016). In the cases of colon cancer, a highly significant correlation was found among lymph node metastases (Chi(2)=9.52, P=0.002), UICC lymph node staging (Chi(2)=5.73, P=0.0167) and mortality by univariate analysis. And Spearman rank correlation analysis demonstrated a significant correlation between lymph node micrometastasis and Dukes' lymph node staging (r=0.314, P=0.008). CONCLUSION: Lymph node micrometastasis possesses considerable value for prognosis of colorectal cancer, but should be used in integration with other indicators.

Adult↗
PubMed2003

Effects of Salvia miltiorrhiza extracts on rat hypoxic pulmonary hypertension, heme oxygenase-1 and nitric oxide synthase.

OBJECTIVE: To investigate the effects of Salvia miltiorrhiza (SM) extracts on the expression of heme oxygenase-1 (HO-1) and nitric oxide synthase (NOS) in small pulmonary arteries (SPAs) of rats with chronic hypoxia. METHODS: After two weeks of hypoxia, rats were treated with diltiazem, and small, median, and large doses of SM extracts. The lungs were tested for the expression and distribution of HO-1, endothelial NOS (eNOS) and inducible NOS (iNOS) by using immunohistochemistry and Western blot method. RESULTS: Median and large doses of SM extracts significantly reduced hypoxia-induced media thickening in the SPAs (similar with diltiazem), recovered repaired ultrastructure injury, decreased HO-1 and iNOS levels, and increased eNOS expression in the SPAs. CONCLUSIONS: Median and large doses of SM extracts play significant roles in inhibiting structural remodeling in rats with hypoxic pulmonary hypertension. These effects might attribute to the suppression of HO-1 and iNOS, and the promotion of eNOS expression under the conditions of hypoxia.

Animals↗
PubMed2003

[Cloning of hemoglobin alpha-chain cDNA sequences from five fishes in cypriniformes].

Oxygen content in water is one of the limit factors to the fish growing. The tolerance of fish to low oxygen content depends on the affinity of hemoglobin to oxygen. The tempt of transgenic fish study is to transfer hemoglobin gene from the fish that tolerates to low oxygen content in water to the fish sensitive to low oxygen condition. Therefore, using hemoglobin gene to breed new varieties may become a main trend in the near future. To explore the underline mechanisms for the variation of hemoglobin property, we have cloned hemoglobin-alpha-chain from five species of Cypriniformes fishes. A pair of consensus degenerate primes were designed basing on N-terminal and C-terminal conservative amino acid of alpha-chain. Using RT-PCR method, alpha-globin gene was amplified and cloned from total RNA which was extracted from blood of five fishes which are widely distribution in China (Cyprinus carpio, Ctenopharyngodon idellus, Carassius auratus, Misgurnus anguillicaudatus, Paramisgurnus dabryanus). Sequence comparison with the existing hemoglobin alpha-chain confirmed that these cDNA fragments were alpha-globin gene of five fishes. The accession numbers in GenBank are AF528156, AF528157, AF528197, AF528198, AF528199 respectively. The cDNA which coding amino acid are all 429 bp. Compared with the amino acid sequences of five fishes, it can be concluded that in five fishes the highest similarity of two fishes which are Paramisgurnus dabryanus and Misgurnus anguillicaudatus is 99.41%, whereas the lowest similarity of two fishes which are Ctenopharyngodon idellus and Paramisgurnus dabryanus is 83.92%. In addition, the sequence similarity and phylogenetic relationship were compared with Within-group method. The result shows that there is much consistent between similarity and phylogenetic relationships from morphological of those near relation species and much connection between similarity and environment of those distant relation species.

Amino Acid Sequence↗
PubMed2003

[Expression of neuron-specific enolase and olfactory marker protein in the developing olfactory mucosa of human fetuses].

OBJECTIVE: To study the expression of neuron-specific enolase (NSE) and olfactory marker protein (OMP) in the developing olfactory mucosa of human fetuses. METHOD: The expression of NSE and OMP in the olfactory mucosa of 6 human fetuses (12, 16, 20, 24, 28 and 34 weeks) was studied using the technique of immunohistochemistry. RESULTS: NSE immunological positive reactions were seen in all 6 fetal mucosa from gestational 12 (G12) to G34, with plenty of positive-stained dual-pole neuron cells. At G12, the positive cells aligned tightly, the cell bodies were localized in the lower portion of olfactory epithelium and the positive-stained area occupied upper 2/3 of fetal nasal mucosa. With the development, the positive cells gradually became multilayer, but the density and the relative area of positive-cells reduced. At G34, the positive cells were located only in upper 1/3 of nasal mucosa. OMP-positive reactions were localized in a few dual-pole neurons at G12, the number was much less than NSE-positive cells in the same fetus. With the development, the OMP-positive cells gradually increased with most of the cell bodies located in the upper portion of epithelium, but number still relatively less than the NSE-positive cells at the same age. CONCLUSION: At G12, there were lots of olfactory neuron in the olfactory mucosa and only a few olfactory neurons had became mature. With the development, the olfactory epithelial area reduced but the number of mature olfactory neurons increased. At the last trimester, fetal olfactory sensor was almost matured.

Female↗
PubMed2003

[Effects of cyclosporin A aerosol on airway hyperresponsiveness in rats].

AIM: To study cyclosporin A (CsA) aerosol for anti-airway hyperresponsiveness (AHR) in sensitized rats. METHODS: Sensitized Sprague-Dawley rats were given cyclosporin A (5, 20 g.L-1) and sodium cromoglycate (SCG, 20 g.L-1) by aerosol (5 min per day), dexamethasone (DXM, 0.5 mg.kg-1) i.p. once per day for 7 d before antigen challenge. The respiratory resistance(R(aw)) and lung dynamic compliance(Cdyn) of the rats induced by methacholine (Mch) were measured 24 h after ovalbumin(OA) challenge. The PC50 changes of R(aw) and PC25 changes of Cdyn were also investigated. RESULTS: Pretreatment with CsA, sodium cromoglycate and dexamethasone inhibited the increase of R(aw) and decrease of Cdyn caused by inhaling Mch. The value of R(aw) PC50 in the CsA(5 g.L-1) group 5.6 g.L-1, the CsA(20 g.L-1) group 6.4 g.L-1, the SCG group 8.3 g.L-1 and the DXM group 9.2 g.L-1, was significantly higher than that of the model group 1.9 g.L-1 (P < 0.05). The value of Cdyn PC25 in the CsA(5 g.L-1) group 4.3 g.L-1, the CsA(20 g.L-1) group 5.4 g.L-1, the SCG group 6.4 g.L-1 and the DXM group 6.2 g.L-1, was significantly higher than that of the model group 1.1 g.L-1 (P < 0.01). CONCLUSION: Anti-AHR of CsA by aerosol in animal model offered an experimental evidence for topical inhalation of CsA in treatment of asthma.

Administration, Inhalation↗
PubMed2003

[Mutation analysis of fibroblast growth factor receptor 3 gene in an achondroplasia family].

OBJECTIVE: To clarify the patients' pathogenic mechanism in an achondroplasia family not according with the genetic law of autosomal dominant inheritance disease at gene level. METHODS: Genomic DNA from peripheral blood of all members in this family was used for amplification of the exon 10 of fibroblast growth factor receptor 3(FGFR3) gene by PCR; mutation was detected by DNA sequencing and identified by restriction endonuclease MaeIII. RESULTS: A new mutation of A to T at nucleotide 1180 was found in patients but not in unaffected members. CONCLUSION: Combined with pedigree analysis, it was summarized that achondroplasia patients in this family might result from this new mutation.

Achondroplasia↗
PubMed2003

[Analysis on mutations of GJB2 gene in Chinese population].

OBJECTIVE: To determine the prevalence and types of GJB2 mutations and to investigate the genetic mechanism in Chinese autosomal recessive deafness. METHODS: The subjects were four Chinese pedigrees (39 individuals) and 50 normal adults. GJB2 was amplified by PCR. The products were digested with restriction enzyme Apa I, then sequenced. RESULTS: Homozygous deletion C at position 232-235 of GJB2 (235delC),which resulted in frameshift mutation, was found in four affected individuals of two pedigrees; the compound heterozygous deletions (235delC/232G to A) were found in two affected individuals in one pedigree. One carrier with 235delC was found in normal controls (1% allele). Two kinds of polymorphisms 79G to A(V27I) and 3 41A to G(E114G) were found in both affected and normal controls. The frequencies of allele for 79G to A and 341A to G in normal controls were 30%, 21%, respectively. CONCLUSION: 235delC mutation of GJB2 was related with Chinese autosomal recessive deafness, and the 232G to A(Ala78Thr) missense mutation was found to be a novel mutation.

Base Sequence↗
PubMed2003

[The clinical analysis of endophthalmitis caused by minor ocular perforation].

OBJECTIVE: To discuss the incidence rate and causes of endophthalmitis caused by minor ocular perforation. To document its damage to the visual function, so as to improve the rate of prevention of this disease. METHODS: The following clinical information of 153 cases with minor ocular perforations from a retrospective study was collected: general conditions, injury objects, wound shape and size, presence or absence of ocular foreign body, associated organic injuries, visual functions in the early stage after injury, speed of occurrence of infection, and positive rate of microbiological tests. The results with the drug treatments and surgical therapy were analyzed. RESULTS: All of 153 cases were followed up from 3 months to 7 years. The visual acuity in 13 cases (8.5%) was over 0.3. 140 cases (91.5%) were less than 0.3. Enucleating was performed in 37 cases (24.2%). CONCLUSION: The patients with minor ocular perforations tend to have good visual acuity in the early stage after injury. But their visual acuity was lost in 4 to 12 hours if rapid and severe infections occurred. The risk of endophthalmitis should be recognized and evaluated on time in the early stage after injury.

Adolescent↗