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Ying Chen

Publications and source records attributed to Ying Chen.

At least 73 records · Page 4Linked to original sources
PubMed2006

RPE65 gene delivery restores isomerohydrolase activity and prevents early cone loss in Rpe65-/- mice.

PURPOSE: Recent in vitro evidence has shown that RPE65 is the isomerohydrolase that converts all-trans retinyl ester to 11-cis retinal, the chromophore for visual pigments in vertebrates. Homozygous RPE65 knockout (Rpe65-/-) mice lack 11-cis retinoids and have early cone degeneration. The purpose of this study is to determine whether RPE65 gene delivery restores the isomerohydrolase activity and normal profile of endogenous retinoids in Rpe65-/- mice. METHODS: Adenovirus-expressing RPE65 (Ad-RPE65) was injected into the subretinal space of Rpe65-/- mice. The expression of RPE65 was determined by immunohistochemistry and Western blot analysis. The isomerohydrolase activity was measured in vitro in eyecup homogenates. Endogenous retinoid profile in the eyecups was analyzed by high-performance liquid chromatography (HPLC). Photoreceptor-specific gene expression was determined with real-time RT-PCR. Cone degeneration was determined by cone-specific staining and counting cones in flatmounted retina. RESULTS: High levels of RPE65 expression from the Ad-RPE65 injection generated robust isomerohydrolase activity in the eyecup of Rpe65-/- mice, at levels comparable to those in wild-type (wt) mice. Consequently, the RPE65 gene delivery resulted in substantial amounts of 11-cis retinal in Rpe65-/- mice. The RPE65 gene delivery prevented the downregulation of cone-specific genes, including both cone opsins and cone tranducin alpha subunit in Rpe65-/- mice. Moreover, the Ad-RPE65 injection also prevented massive cone degeneration at early ages of Rpe65-/- mice. CONCLUSIONS: RPE65 gene delivery generates isomerohydrolase activity and restores retinoid profile in Rpe65-/- mice. Regeneration of 11-cis retinal is essential for survival of cone photoreceptors.

Adenoviridae↗
PubMed2006

The roles of three palmitoylation sites of RPE65 in its membrane association and isomerohydrolase activity.

PURPOSE: RPE65, a membrane-associated protein predominantly expressed in the retinal pigment epithelium, is the isomerohydrolase in the retinoid visual cycle. Three cysteine (Cys) residues, Cys231, Cys329, and Cys330, in RPE65 have been shown to be palmitoylated and have been suggested to be responsible for its membrane association. The purpose of this study was to define the role of these Cys residues in palmitoylation, membrane association, and isomerohydrolase activity of RPE65. METHODS: The three Cys residues in RPE65 were replaced by Alanine (Ala) with site-directed mutagenesis. The mutant protein levels and subcellular localizations were determined by Western blot analysis and subcellular fractionation, respectively. Their enzymatic activities were evaluated with the in vitro isomerohydrolase activity assay. Palmitoylation of the mutants was examined by labeling of the protein with [3H]-labeled palmitic acid. RESULTS: Mutation of any single residue of these three Cys significantly reduced protein levels of RPE65. Similar to wild-type RPE65, however, all three single Cys mutants were predominantly present in the membrane fraction. Mutations of any one or two of these Cys substantially weakened the isomerohydrolase activity of RPE65, whereas mutations of all three Cys (triple mutant) completely abolished the enzymatic activity. However, this triple Cys mutant was still palmitoylated and associated with the membrane, although at a reduced level. CONCLUSIONS: There are additional yet to be identified palmitoylation sites in RPE65. The structural distortions induced by the Cys mutations may be responsible for the mislocalization and decreased isomerohydrolase activities of RPE65.

Alanine↗
PubMed2006

Predictors of relapse in a prospective study of fluoxetine treatment of major depression.

OBJECTIVE: Loss of response to a previously effective antidepressant is a common clinical problem. Retrospective analyses have shown that the pattern of response during antidepressant treatment (late onset and persistent versus other patterns) can be used to predict relapse during continuation and maintenance treatment and possibly to identify placebo responses to treatment. This study was designed to test the predictive value of response pattern prospectively and to examine the data for other predictors of relapse. METHOD: Five hundred seventy persons with major depressive disorder were treated with fluoxetine for 12 weeks and their pattern of response was determined. Those who responded (N=292) underwent random assignment, under double-blind conditions, to continue taking fluoxetine or to switch to placebo for 52 weeks or until relapse. Survival analysis was used to examine the effect of covariates on relapse. RESULTS: Although fluoxetine was significantly more effective than placebo during maintenance treatment, this chronically ill group had a high rate of relapse. Contrary to previous findings, a pattern of acute response was not predictive of relapse. Chronicity, symptom severity, a neurovegetative symptom pattern, and female gender were all associated with a significantly greater risk of relapse, with no difference observed between fluoxetine and placebo. CONCLUSIONS: The pattern of response to acute treatment appears to be inconsistently predictive of relapse. There is a high rate of relapse with both active medication and placebo in patients with chronic depression. Illness characteristics predict loss of response both to fluoxetine and to placebo. No variable examined was predictive of differential relapse rates between fluoxetine and placebo.

Adult↗
PubMed2006

Soy protein isolate induces CYP3A1 and CYP3A2 in prepubertal rats.

Feeding soy diets has been shown to induce cytochrome P450s in gene family CYP3A in Sprague-Dawley rat liver. We compared expression of CYP3A enzymes on postnatal Day 33 (PND33) rats fed casein or soy protein isolate (SPI+)-based AIN-93G diets continuously from gestational Day 4 through PND33 or the diets were switched on PND15 (n = 3-6 litters) to examine the potential imprinting effects of soy on drug metabolism. In addition rats were fed casein, SPI+, SPI+ stripped of phytochemicals (SPI-), or casein diets supplemented with the soy-associated isoflavones genistein or daidzein from weaning through PND33 to examine the hypothesis that the isoflavones are responsible for CYP3A induction by soy feeding. Feeding SPI either continuously or from weaning induced hepatic CYP3A1 and CYP3A2 mRNA, apoprotein, and CYP3A-dependent testosterone 6beta-hydroxylase activity in liver microsomes 2- to 5-fold (P < 0.05). CYP3A mRNA expression was also elevated 2- to 3-fold in the jejunum of SPI-fed rats (P < 0.05). CYP3A was not induced in livers of rats switched to casein from soy at weaning. Induction of CYP3A1 also did not occur in rats fed SPI-, but CYP3A2 mRNA and apoprotein were induced (P < 0.05) in females fed SPI-. Offspring weaned onto genistein-supplemented diets had no elevation of CYP3A mRNAs or apoproteins. Weaning onto daidzein diets increased CYP3A2 mRNA and apoprotein expression in male rats (P < 0.05). These data suggest that early soy consumption may increase the metabolism of a wide variety of CYP3A substrates, but that soy does not imprint the expression of CYP3A enzymes. Effects on CYP3A1 expression appear to be primarily due to phytochemical components of SPI other than isoflavones. In contrast, consumption of soy protein and daidzein appear to be associated with the induction of CYP3A2.

Animals↗
PubMed2006

Global analysis of differential luminal epithelial gene expression at mouse implantation sites.

Although implantation types differ between species, the interaction between blastocyst trophectoderm and apical surface of the uterine epithelium is a common event during the implantation process. In this study, uterine luminal epithelium at implantation and inter-implantation sites was isolated by enzymatic digestion and used for microarray analysis. In a mouse microarray containing 12 345 unigenes, we found 136 genes upregulated more than twofold at the implantation site, while 223 genes were downregulated by at least twofold. Reverse transcription-PCR was used to verify the differential expression of seven upregulated and six downregulated genes chosen randomly from our microarray analysis, and the expression trends were similar. The differential expression patterns of eight upregulated genes were verified by in situ hybridization. Compared with the inter-implantation site on day 5 of pregnancy and the uterus on day 5 of pseudopregnancy, protease, serine, 12 neurotrypsin, endothelin-1, gamma-glutamyl hydrolase, Ras homolog gene family, member U, T-cell immunoglobulin, and mucin domain containing 2, proline-serine-threonine phosphatase-interacting protein 2, 3-monooxgenase/tryptophan 5-monooxgenase activation protein, gamma-polypeptide, and cysteine-rich protein 61 (Cyr61) were upregulated in the luminal epithelium at implantation site on day 5 of pregnancy. These genes may be related to embryo apposition and adhesion during embryo implantation. Cyr61, a gene upregulated at the implantation site, was chosen to examine its expression and regulation during the periimplantation period by in situ hybridization. Cyr61 mRNA was specifically localized in the luminal epithelium surrounding the implanting blastocyst at day 4 midnight and on day 5 of pregnancy, and in the activated uterus, but not expressed in inter-implantation sites and under delayed implantation, suggesting a role for Cyr61 in mediating embryonic-uterine dialog during embryo attachment. Our data could be a valuable source for future study on embryo implantation.

Animals↗
PubMed2006

Interaction of human immunodeficiency virus (HIV) glycans with lectins of the human immune system.

Approximately half of the molecular mass of gp120, the receptor-binding envelope protein of human immunodeficiency virus (HIV), consists of N-linked glycans. Nearly half of these glycans are of the high mannose type. These high mannose glycans furnish a rich forest of mannose residues on the virus surface making HIV a prime target for interaction with mannose-specific lectins of the immune system. This review focuses on the known interactions between gp120 and immune system lectins some of which HIV appears to exploit. The effect of variation in glycosylation of gp120, especially with respect to clades of HIV, on binding of immune system lectins is highlighted.

Animals↗
PubMed2006

The identification and characterization of a testis-specific cDNA during spermatogenesis.

Using bioinformatics and experimental validation, we obtained a cDNA (named srsf) which was exclusively expressed in the mouse testes. RT-PCR analysis showed that srsf mRNA was not expressed in the gonad during the sex determination period or during embryogenesis. In developing mouse testis, srsf expression was first detected on post-natal day 10, reached its highest level on day 23, and then reduced to and remained at a moderate level throughout adulthood. In situ hybridization analysis demonstrated that srsf mRNA was expressed in pachytene spermatocytes and round spermatids in the testes. The predicted protein contains one RNA-binding domain (RBD) and a serine-arginine rich domain (RS), which are characterized by some splicing factors of SR family members. These findings indicate that srsf may play a role during spermatogenesis.

Amino Acid Sequence↗
PubMed2006

[Preliminary study on adult odontoblast culture in situ].

PURPOSE: To establish an in situ culture model of adult odontoblasts. METHODS: Thirty intact and healthy third molars freshly prepared from 20-30 year old individuals were randomly divided into three groups. Each group had 10 molars. Group 1 was pulp tissue extraction group. Group 2 was serum-containing culture group. Group 3 was serum-free culture group. The root was dissected from the crown and the pulp was pulled out to make odontoblasts remaining in the crown. The odontoblasts were cultured in situ either in medium containing serum or serum-free medium for up to 7 days. The growth status of the cells was examined by light microscopy and cell morphology and distribution was analyzed by scanning electron microscopy. Cell viability was determined by trypan blue staining. RESULTS: After pulp removal at room temperature, odontoblasts remained in the wall of the pulp chamber, and kept viable and good morphology during the 7-day culture. CONCLUSION: We have successfully established an in situ culture model of adult primary odontoblasts in either serum-containing or serum-free medium.

Adult↗
PubMed2006

[Expressions of nm23, P53 and S100A4 proteins and their relationships with metastasis potential in gastric carcinoma].

OBJECTIVE: To investigate the expression levels of nm23, P53, and S100A4 in gastric carcinoma and their relationships with clinicopathologic parameters and metastasis potential. METHODS: Pathological specimens from gastric carcinoma,matched para-tumor tissues, metastatic lymph node and distant metastatic tissues were examined for the expression levels of nm23, P53, and S100A4 proteins by tissue microarray technique and immunohistochemistry. RESULTS: The expression levels of P53 and S100A4 were upregulated (P< 0.01), while the expression of nm23 downregulated (P< 0.05) in gastric carcinoma compared with non-tumor tissues. S100A4 expression was significantly higher in distant metastatic tissues, while nm23 lower in metastatic lymph nodes than those in cancer tissues. Upregulating expression levels of nm23, P53, and S100A4 were significantly correlated with some malignant behaviour of gastric cancer. The expression rates of nm23+/P53+, P53+/S100A4+, and nm23+/S100A4+ immunohistochemical phenotypes were 48/74 (64.9%), 50/74 (67.6%), and 39/74 (52.7%). P53+/S100A4+, nm23+/S100A4+, and nm23+/P53+/S100A4+ phenotypes were associated with high metastasis potential of gastric cancer. CONCLUSIONS: Alteration of nm23, P53, and S100A4 expression may contribute to the development of gastric carcinoma. Nm23 and S100A4 proteins play a critical role in tumor metastasis. Co-detection of the expression of P53, nm23, and/or S100A4 can be used to evaluate high metastasis potential of gastric cancer.

Female↗
PubMed2006

[The application of multi-slice computed tomograph in diagnosis and operation of hypopharyngeal carcinoma].

OBJECTIVE: To evaluate the clinical application of multi slice CT(MSCT) in hypopharyngeal carcinoma and serve otolaryngologist to institute proper operation. METHOD: Forty-five patients with hypopharyngeal carcinoma scanned by MSCT were studied and confirmed by operation and pathologic examination. The operation material were retrospectively analyzed. All the cases were used for the enhancement scanning, whose scope was from hard palate to cervical segments of esophagus. RESULT: Of 45 cases, 34 cases derived from piriform fossa, 7 cases were from the postcricoid region and 4 cases were in the posterior wall of hypopharynx. The tumor showed isodense or mixed density and slightly enhancement, piriform fossa became narrow or disappeared, retropharyngeal soft tissue thickened, laryngeal cartilage and esophageal ostium were invaded and lymph nodes of neck became metastasis. The tumor pushed the annular and arytenoids cartilage displacement anteriorly; the thyroid arytenoidal gap and cricothyroid joint were widened. The operation plan that was made according as MSCT was almost agreed with actual operation. The consistent rate is 91.1% (41/45). CONCLUSION: MSCT examination can accurately diagnose and exhibit the extension of the tumors and detect metastasis to lymph nodes, and provide reliable basis for surgery therapy.

Adult↗
PubMed2006

[Cause analysis and management of severe dislocated or subluxated intraocular lenses in the capsular bag].

OBJECTIVE: To analyze the causes of severe dislocated and subluxated intraocular lenses (IOL) in capsular bag and the relevancy with abnormal capsular constitution. METHODS: The abnormality of capsular and the position of IOL were retrospectively analyzed by slit lamp and microscope in dilated pupil. Surgeries were performed in all of 31 cases in order to exchange or reposit the dislocated or subluxated lOL. RESULTS: Among 31 cases, there were 20 cases with the dislocated or subluxated IOL in the earlier postoperative period and 11 cases in the later postoperative period. The subluxated IOL in 5 cases (16.1%) were caused by the large rupture of the posterior capsular, and by the rupture of the posterior capsular in 9 cases (29.0%). A upward subluxated IOL developed in one case (3.2%) as the result of small rupture in the equater capsular. The subluxatd IOL in the anterior chamber in two cases (6.5%) was induced by the radial rupture of residual anterior capsular. The size of the IOLs in 2 cases were not matched to the diameter of the capsule bag. The dislocated IOL into the vitreous in 2 cases was caused by the rupture of the superior capsular. The subluxated IOL in 2 cases (6.5%) was caused by the zonal finers rupture due to trauma. The severe disfiguration of the IOL haptic was found in one case. The dislocated IOL in 6 cases (19.4%) was caused by asymmetric capsular shrinkage. A subluxated IOL in one case was resulted from the zonular defects with pseudoexfoliation syndrome. The postoperative corrected visual acuity was 0.5 - 1.0 in 24 eyes, 0.1 - 0.4 in 6 eyes, and 0.05 in one eye. CONCLUSIONS: There are several causes for the dislocated or subluxated IOL. The correction of the IOL position should depend on the cause for the dislocated or subluxated IOL.

Adolescent↗
PubMed2006

[Evaluation of maximum intensity projection in HRCT in the diagnosis of the destruction of ossicular chain in chronic otitis media].

OBJECTIVE: To observe the ossicular chain structure with maximum intensity projection (MIP) and to evaluate the diagnostic value of it in the destruction of ossicular chain in chronic otitis media (COM). METHOD: Sixty-eight patients (136 ears) were scanned with HRCT. The original data was processed with MIP reconstruction technique. The images of the ossicular chain structure in normal ears were observed, while the images in suffering ears were compared with the findings in operation. RESULT: In normal ears, the ossicular chain structure was shown clearly by MIP, which can also display three-dimensional images of the ossicular chain. In the suffering ears of chronic otitis media of cholesteatoma type, granuloma type and simple type, MIP displayed the destruction of ossicular chain in 39 ears, 5 ears and 0 ear respectively, which was observed in 39 ears, 6 ears and 0 ears respectively in operation. CONCLUSION: MIP technique in HRCT can display the ossicular chain spatial structure clearly, which is very helpful to evaluate the destruction of ossicular chain in chronic otitis media (COM) and to make accurate operation plan.

Adolescent↗
PubMed2006

[Value of serum inhibin B measurement in predicting ovarian response in controlled ovarian hyperstimulation for in vitro fertilization cycle].

OBJECTIVE: To explore the value of serum inhibin measurement in predicting ovarian response in infertile patients undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF) cycle. METHODS: A total of 37 patients undergoing their first cycles of IVF treatment were studied and serum estradiol (E(2)), progesterone (P), inhibin (INH) B, INHA levels were detected on days 2 - 4 and 21 of the previous cycle, on day 5 of gonadotropin therapy (day 5), hCG injection day, oocyte retrieval day and at middle luteal phase of the IVF cycle. According to number of oocytes, peak E(2) concentration and presence or absence of ovarian hyperstimulation syndrome (OHSS), the 37 patients were allocated into two groups: poor ovarian response group (group A), normal and high response group (group B). Characteristics of the treatment cycle and INH, E(2), P levels were analyzed. A multiple logistic regression model and receiver operating characteristic (ROC) analysis were then used for all possible prognostic variables to evaluate the value of different hormone in predicting ovarian response. The sensitivity and specificity were calculated at the discriminating cut-off point. RESULTS: (1) In group A, basal serum INHB level, INHB and INHA levels on day 5 of recombinant FSH (rFSH) stimulation were significantly lower than group B (P < 0.05), and basal serum INHB levels were (37 +/- 35), (91 +/- 90) ng/L respectively, INHB levels on day 5 of rFSH stimulation were (194 +/- 157), (2254 +/- 4765) ng/L respectively, INHA levels on day 5 of rFSH stimulation were (36 +/- 35), (91 +/- 90) ng/L respectively in groups A and B. (2) There was positive correlation between oocytes number and basal inhibin B and dynamic serum inhibin B levels, inhibin A and E(2) levels of rFSH therapy (INHB: r = 0.39 - 0.67, P < 0.05; INHA: r = 0.43 - 0.59, P < 0.01; E(2): r = 0.50 - 0.60, P < 0.01). (3) ROC analysis: day 5 inhibin B had the largest area under curve (AUC) 0.948 (95% CI: 0.871 - 1.025), indicating that a threshold of 400 ng/L gave 82.8% sensitivity, and 99.1% specificity. CONCLUSIONS: The basal INHB levels and INHB measured on day 5 of rFSH stimulation may offer accurate and early prediction of ovarian response. Day 5 INHB levels are the best predictor of ovarian response.

Adult↗
PubMed2006

[Allelic loss of 6q16.3 microsatellite DNA in childhood acute lymphoblastic leukemia and bioinformatics analysis].

OBJECTIVE: To locate the cluster region of loss of heterozygosity (LOH) in children with acute lymphoblastic leukemia (ALL), and explore the new tumor suppressor gene. METHODS: Allelic loss was analyzed by PCR with 15 microsatellite markers mapping on 6q16.3. The LOH was analyzed by bioinformatics. The relationship between LOH and clinical factors was further analyzed. RESULTS: The frequency of LOH at least at one loci on 6q16.3 was 32.7%. The LOH in relapsed patients was higher than those in not relapsed. The higher frequency of LOH was observed in two regions of D6S1709-D6S1028 and D6S2160-D6S1580 at 6q16.3. GRIK2 may be a candidate of tumor suppressor gene. There are 12 ESTs may carry out new anti-oncogene. Patients with 6q LOH had higher WBC counts (P < 0.01), blast cells percentage (P < 0.01), relapse rate (P < 0.05) and chromosomal aberration (P < 0.05). CONCLUSION: D6S1709-D6S1028 and D6S2160-D6S1580 are two regions of minimus deletion on 6q16.3 in which tumor suppressor gene may exist. The LOH on 6q16.3 may be a prognostic index of children with ALL.

Adolescent↗
PubMed2006

[Extraction, identification and primary investigation of adhesion specificity of Lactobacillus sp].

Lactobacillus L15, a strain of Lactobacillus sp. isolated from the intestinal tract of healthy Paralichthys olivaceus, and Lactobacillus acidlophilus ATCC4356 were used to investigate their specific adhesions. It was shown that cell surface proteins of two strains could be extracted by 5 mol/L lithium chloride( LiCl). Two surface proteins with molecular weights of 61.8 kDa and 54.6 kDa were identified to mediate the adhesion to intestinal mucus of Paralichthys olivaceus and Common carp respectively by the method of Western blotting, and the two novel proteins were named as MAPPpo1 and MAPPcc. In Lactobacillus acidlophilus ATCC4356, two proteins of 43.0 kDa and 63.3 kDa were identified to mediate the adhesion to intestinal mucus of Paralichthys olivaceus. Nevertheless, only 43.0 kDa protein was identified to mediate the adhesion to intestinal mucus of Common carp. Furthermore, the mucus proteins which participated the adhesion as the bacteria receptors were identified by the same method and it was found that L15 and ATCC4356 had the same receptors.There were 29.7 kDa and 30.3 kDa proteins in the intestinal mucus of Paralichthys olivaceus and only the 26.2 kDa protein was testified in the intestinal mucus of Common carp. It is demonstrated that the adhesion of Lactobacillus to mucus is dependent on the strain specificity, as well as host specificity.

Adhesins, Bacterial↗
PubMed2006

[Effect of hydroxyethyl starch on vascular reactivity of rat during hemorrhagic shock].

OBJECTIVE: To study the effect of hydroxyethyl starch (HES) on vascular reactivity of rat during hemorrhagic shock and its mechanism. METHODS: Forty SD rats were randomly divided into 5 groups: normal control group, shock group, sodium chloride (SC) group, HES 130/0.4 group and HES 200/0.5 group with 8 rats in each group. Rats were hemorrhaged and maintained mean arterial pressure (MAP) at 40 mm Hg (1 mm Hg=0.133 kPa) for 30 minutes, then rats were infused with fluids to restore and maintain MAP at 70 mm Hg for 60 minutes. The infusion volumes of each fluid to maintain MAP were recorded. The responses of MAP to norepinephrine (NE) were measured before shock, at 30, 60 and 90 minutes during hemorrhagic shock. Concentrations of nitric oxide (NO) and nitric oxide synthase (NOS) of plasma were measured at 90 minutes during hemorrhagic shock. RESULTS: The infusion volumes of each fluid to maintain MAP were significantly different (all P<0.01). HES 200/0.5 group<HES 130/0.4 group<SC group. In HES 130/0.4 group and HES 200/0.5 group at 90 minutes during hemorrhagic shock, the responses of MAP to NE were improved significantly compared with those of SC group (both P<0.05), plasma contents of NO and NOS were reduced markedly compared with those of SC group (P<0.05 or P<0.01). CONCLUSION: HES can improve vascular reactivity during hemorrhagic shock by inhibiting plasma contents of NO and NOS.

Animals↗
PubMed2006

[Cell brain abnormalities in carcinogenesis].

Cancer seriously threatens the health of humans. The mechanism underlying the carcinogenesis, however, is unclear. Among all the related hypotheses, the lately postulated 'cell brain' theory, challenging the conventional theory that gene abnormalities are the major players in carcinogenesis, is catching more and more attentions. According to this theory, the complex composes of the centrosome, centrioles, and connecting microtubules, and acts as the commandeering center of a cell in the structures and functions, equals to the brains of human being and animals, centering all the cellular activities. As far as carcinogenesis is concerned, cancer was interpreted by this theory as a brain illness' rather than a genetic disease. This article, based on the latest findings, reevaluated the roles of the composing parts of cell brain, discussed their correlations to cancer development, and further explored the mechanisms of carcinogenesis including hepatocarcinogenesis. It will contribute not only to improving cancer diagnosis and prevention but also to the design of novel anticancer agents, particularly the centrosome/cell brain-targeting agents.

Animals↗