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Biomedical subjects

Ying Huang

Publications and source records attributed to Ying Huang.

At least 199 records · Page 11Linked to original sources
PubMed2002

TC21 mediates transformation and cell survival via activation of phosphatidylinositol 3-kinase/Akt and NF-kappaB signaling pathway.

The signaling pathways of TC21-mediated transformation and cell survival are not well-established. In this study, we have investigated the role of PI3-K/Akt signaling pathway in oncogenic-TC21-mediated transformation and cell survival. We found that oncogenic-TC21 stimulated the PI3-K activity. This was associated with the activation of Akt, a key component of PI3-K signaling pathway. We also found that TC21 interacted and formed complex with PI3-K. Mutations in the GTP-binding region of TC21, which enhanced GTP-binding potential of this protein, also stimulated its association with PI3-K, suggesting that PI3-K may preferentially interact with the GTP-bound form. Suppression of PI3-K and Akt by specific inhibitors LY294002 and Wortmannin reversed TC21-induced transformation. Likewise, inhibition of PI3-K activity by the PI3-K phosphotase PTEN reduced TC21-mediated focus formation in NIH3T3 cells. Investigation of TC21's effect on cell survival revealed that mutant-TC21 expressing cells were more resistant to etoposide- and cisplatin-induced cell death, and this was associated with the activation of anti-apoptotic protein NF-kappaB, a downstream target of Akt. Treatment of PI3-K inhibitor LY294002 significantly suppressed TC21-mediated NF-kappaB activation. In conclusion, we have identified PI3-K as an effector of TC21 and demonstrated that the PI3-K/Akt signaling pathway plays important roles in TC21-mediated transformation and cell survival.

3T3 Cells↗
PubMed2002

Antidepressant-like profile and reduced sensitivity to rolipram in mice deficient in the PDE4D phosphodiesterase enzyme.

Pharmacological inhibition of type 4 cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase (PDE4) produces antidepressant-like effects in animals; however, it is not known which of the four PDE4 subtypes mediates these actions. In the present study, immunoblot analysis showed loss of phosphodiesterase 4D (PDE4D) expression in the cerebral cortex and hippocampus of PDE4D knockout (PDE4D-/-) mice, but unchanged PDE4A and PDE4B expression, relative to the wild type (PDE4D+/+) and heterozygous knockout (PDE4D+/-) mice. This reduced expression was accompanied by a reduction in PDE4 activity, while non-PDE4 activity was unchanged. PDE4D-/- mice exhibited decreased immobility in tail-suspension and forced-swim tests, which is indicative of an antidepressant-like effect on behavior. Desipramine and fluoxetine produced similar antidepressant-like effects in all three genotypes, even though their behavioral baselines differed markedly. By contrast, the PDE4 inhibitor rolipram only produced antidepressant-like effects in PDE4D+/+ mice. Consistent with this, rolipram potentiated isoproterenol-induced cyclic AMP formation only in the PDE4D+/+ mice. These results suggest that PDE4D is an essential mediator of the antidepressant-like effects of rolipram, and that PDE4D-regulated cyclic adenosine monophosphate signaling may play a role in the pathophysiology and pharmacotherapy of depression.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2002

An integrated, stacked microlaboratory for biological agent detection with DNA and immunoassays.

An integrated, stacked microlaboratory for performing automated electric-field-driven immunoassays and DNA hybridization assays was developed. The stacked microlaboratory was fabricated by orderly laminating several different functional layers (all 76 x 76 mm(2)) including a patterned polyimide layer with a flip-chip bonded CMOS chip, a pressure sensitive acrylic adhesive (PSA) layer with a fluidic cutout, an optically transparent polymethyl methacrylate (PMMA) film, a PSA layer with a via, a patterned polyimide layer with a flip-chip bonded silicon chip, a PSA layer with a fluidic cutout, and a glass cover plate layer. Versatility of the stacked microlaboratory was demonstrated by various automated assays. Escherichia coli bacteria and Alexa-labeled protein toxin staphylococcal enterotoxin B (SEB) were detected by electric-field-driven immunoassays on a single chip with a specific-to-nonspecific signal ratios of 4.2:1 and 3.0:1, respectively. Furthermore, by integrating the microlaboratory with a module for strand displacement amplification (SDA), the identification of the Shiga-like toxin gene (SLT1) from E. coli was accomplished within 2.5 h starting from a dielectrophoretic concentration of intact E. coli bacteria and finishing with an electric-field-driven DNA hybridization assay, detected by fluorescently labeled DNA reporter probes. The integrated microlaboratory can be potentially used in a wide range of applications including detection of bacteria and biowarfare agents, and genetic identification.

Biological Warfare↗
PubMed2002

Measurement of HCV RdRp activity with C-terminal 21 aa truncated NS5b protein: optimization of assay conditions.

The non-structural protein 5b (NS5b) of hepatitis C virus (HCV), bearing an RNA-dependent RNA polymerase (RdRp) activity, is considered as a new target of antiviral therapy. We expressed and purified the C-terminal 21 amino acid truncated NS5b protein fused with glutathione S-transferase (GST-5bC21) using Escherichia coli. With the highly purified GST-5bC21 protein, we established an in vitro assay system for RdRp activity by using poly(C) as the template and a 12 mer oligo(rG) as the primer. The optimal conditions for testing various concentrations of template, primer and proteins were determined to 22 degrees C and a pH of 7.5. The addition of 2.5 mM Mn(2+) increased the activity profoundly, to a level fivefold higher than that in the presence of 10 mM Mg(2+). At higher concentrations of Mn(2+), GST-5bC21 is stable as compared with previously reported full-length NS5b expressed using insect cells or NS5b protein with the C-terminal 18 amino acids deleted. This sensitive and easy to use quantitative assay system will provide a stable system for the screening of inhibitors for HCV RdRp.

Journal Article↗
PubMed2002

Long-term outcome and quality of life after the Swenson procedure for Hirschsprung's disease.

BACKGROUND/PURPOSE: The aim of this study was to investigate long-term outcome and quality of life after the Swenson operation for rectosigmoid Hirschsprung's Disease (HD). METHODS: Forty-five patients who underwent the Swenson procedure for HD underwent follow-up for 8 to 16 years. Long-term outcome and quality of life were assessed by interviews and questionnaires including scoring systems. Forty-four healthy children with similar age, sex, and education level distributions used as controls. RESULTS: In 45 patients, 23 (51.1%) had bowel dysfunction. Seventeen patients (37.8%) suffered from fecal soiling. According to the clinical bowel function scoring system, the patients' scores (7.6 +/- 2.1) were significantly lower than those of the controls (11.4 +/- 0.6; P <.05). Because of poor fecal continence, 25 patients (55.7%) had to restrict their foods. School absence occurred in 6 (13.3%) patients. Seven patients (15.6%) had problems in peer relationships. According to the Quality-of-Life Scoring Criteria, 86.7% patients had good or fair quality of life. The patients' scores (7.7 +/- 2.9) were significantly lower than those of the controls (11.6 +/- 0.7; P <.05). And the scores of patients who had fecal soiling and incontinence (6.3 +/- 2.7) were significantly lower than those of patients without fecal soiling and incontinence (8.4 +/- 2.6; P <.05). CONCLUSIONS: Although most patients had good or fair quality of life after surgical correction for HD, the long-term outcome and quality of life are not as good as surgeons expected. The bowel function and quality of life of the patients were poorer than those of healthy children. Fecal soiling is very common and affects patients' quality of life. Long-term regular follow-up is indispensable. Close attention should be paid to minimizing bowel dysfunction for patients with HD postoperatively to improve their quality of life.

Adolescent↗
PubMed2002

Proposal to combine the genera Actinobispora and Pseudonocardia in an emended genus Pseudonocardia, and description of Pseudonocardia zijingensis sp. nov..

The 16S rDNA sequences of four strains, i.e. three type strains of Actinobispora and strain 6330T, were determined and compared with those of representatives of the family Pseudonocardiaceae by using two tree-making algorithms. All the validly described species of the genera Actinobispora and Pseudonocardia were consistently recovered as a mixed group in phylogenetic trees, and were distinct from the other genera of the family Pseudonocardiaceae. Strain 6330T formed a distinct phyletic line in the 16S rDNA tree and was most closely associated with the type strain of Actinobispora aurantiaca. The use of specific PCR primers designed for differentiating the genus Pseudonocardia from other genera of the family Pseudonocardiaceae showed that all the Actinobispora species and strain 6330T have the same amplified 640 bp 16S rDNA fragment as members of the genus Pseudonocardia. The DNA-DNA relatedness, chemotaxonomic and phenotypic data also supported classification of these taxa in the genus Pseudonocardia, and distinguished each from the others. On the basis of these observations, it is proposed that the genera Actinobispora and Pseudonocardia be combined in an emended genus Pseudonocardia, and that strain 6330T be classified in the same genus as Pseudonocardia zijingensis sp. nov. The type strain is 6330T (= AS 4.1545T = JCM 11117T).

Actinomycetales↗
PubMed2002

Description of Lentzea flaviverrucosa sp. nov. and transfer of the type strain of Saccharothrix aerocolonigenes subsp. staurosporea to Lentzea albida.

A distinct actinomycete isolated from soil was subjected to polyphasic taxonomic analysis. It is demonstrated by comparative 16S rDNA gene sequencing that the organism, designated strain AS 4.0578T, represents a novel species of the genus Lentzea. The phylogenetic results also showed that it formed a monophyletic lineage distinct from the available members of the genera Lentzea, Lechevalieria and Saccharothrix. The organism was distinguished from all the validly described type strains of the genus Lentzea by a combination of phenotypic features and DNA-DNA hybridization. It is proposed, therefore, that strain AS 4.0578T (= JCM 11373T) be classified in the genus Lentzea as Lentzea flaviverrucosa sp. nov. In addition, it is proposed that Saccharothrix aerocolonigenes subsp. staurosporea NRRL 11184T be transferred to Lentzea albida on the basis of phylogenetic analysis, DNA-DNA homology, nucleotide signatures and phenotypic properties.

Actinomycetales↗
PubMed2002

Rothia amarae sp. nov., from sludge of a foul water sewer.

A Gram-positive bacterium, strain J18(T), isolated from sludge of a foul water sewer, was subjected to a polyphasic taxonomic study. Phylogenetic analysis of the bacterium based on its 16S rDNA sequence showed that it belongs to the genus Rothia and forms a distinct phyletic clade with the type strain of Rothia nasimurium. Morphological, physiological and chemotaxonomic characteristics supported the assignment of this organism to the genus Rothia and distinguished it from the type strains of all validly described Rothia species. Therefore, it is proposed that this bacterium be classified in the genus Rothia as Rothia amarae sp. nov. The type strain is strain J18(T) (= AS 4.1721(T) = JCM 11375(T)).

Base Composition↗
PubMed2002

Similar regulation of cell surface human T-cell leukemia virus type 1 (HTLV-1) surface binding proteins in cells highly and poorly transduced by HTLV-1-pseudotyped virions.

Little is known about the requirements for human T-cell leukemia virus type 1 (HTLV-1) entry, including the identity of the cellular receptor(s). Previous studies have shown that although the HTLV receptor(s) are widely expressed on cell lines of various cell types from different species, cell lines differ dramatically in their susceptibility to HTLV-Env-mediated fusion. Human cells (293, HeLa, and primary CD4(+) T cells) showed higher levels of binding at saturation than rodent (NIH 3T3 and NRK) cells to an HTLV-1 SU immunoadhesin. A direct comparison of the binding of the HTLV-1 surface glycoprotein (SU) immunoadhesin and transduction by HTLV-1 pseudotyped virus revealed parallels between the level of binding and the titer for various cell lines. When cells were treated with phorbol myristate acetate (PMA), which down-modulates a number of cell surface molecules, the level of SU binding was markedly reduced. However, PMA treatment only slightly reduced the titer of murine leukemia virus(HTLV-1) on both highly susceptible and poorly susceptible cells. Treatment of target cells with trypsin greatly reduced binding, indicating that the majority of HTLV SU binding is to proteins. Polycations, which enhance the infectivity of several other retroviruses, inhibited HTLV-1 Env-mediated binding and entry on both human and rodent cells. These results suggest that factors other than the number of primary binding receptors are responsible for the differences in the titers of HTLV-1 pseudotypes between highly susceptible cells and poorly susceptible cells.

3T3 Cells↗
PubMed2002

Effects of recombinant human growth hormone on rat septic shock with intraabdominal infection by E. coli.

AIM: To investigate the therapeutic effects of recombinant human growth hormone (rhGH) on rat septic shock with intraabdominal infection by E. coli and its possible mechanism. METHODS: 76 SD rats were divided into 3 groups randomly: control group (group C, n=16) without any special treatment, septic shock group (group S, n=30) received bolus injection of E.coli (1X10(10) cfu x L(-1), 15 ml x kg(-1), ip), treated group (group T, n=30) received bolus injection of E.coli, and then followed by rhGH injection (2.25 U x k g(-1) x d(-1), im). Group S and group T were further divided into 1d and 3d subgroups, respectively (n=15 each). Mean arterial pressure (MAP), levels of plasma TNFalpha and endotoxin and leukocyte count were determined on 1st day and 3rd day after E.coli injection. Another 39 SD rats were divided into groups C, S and T (n=13 each) just for observing survival rate within 1 week. RESULTS: (1) On 1st and 3rd day, MAP in group S decreased markedly, and MAP on 1st day lowered more than that of 3rd day (P<0.01), while MAP in group T just decreased slightly. The survival rate within 1 week was much higher in group T (84.6 %) than in group S (46.2 %) (P<0.01). (2)On 1st day, plasma TNFalpha and endotoxin elevated significantly in group S and group T (P<0.05), and endotoxin in group S had more increase (P<0.01). On 3rd day, TNFagr in group S returned to the level of group C (P>0.05),while TNFagr in group T went down below the level of group C(P<0.01). On 3rd day, endotoxin in group S declined, but was still higher than that of group C (P<0.01), endotoxin in group T returned to the level of group C (P>0.05). (3) On 1st day, neutrophil ratio in total leukocyte count in both group S and group T increased significantly (P<0.05 vs group C). CONCLUSION: rhGH showed beneficial effects on rat septic shock. The possible mechanisms may involve the attenuation of bacteria/endotoxin translocation and decreased systemic endotoxin level; inhibition of the production and release of TNFalpha; improved circulatory function; improved systemic host defenses and maintenance of intestinal mucosa barrier.

Abdomen↗
PubMed2002

[Actions of neuroactive steroids in neurons].

The term "neuroactive steroids" applies to those steroids that have biological activities in nervous system. These neuroactive steroids can be divided into three categories according to the mechanism of their effects: (1) Effects mediated by membrane receptors including GABAA receptor and NMDA receptor that are ion channels; (2) Effects mediated by membrane receptors that are coupled with second messenger systems; (3) Effects mediated by intracellular receptors which in turn modulate gene expression. These neuronal effects of steroids, especially modulation of the ion-channel receptor and G protein--coupled receptor, have drawn more attention of the researchers.

Adrenal Cortex Hormones↗
PubMed2002

[Diamide and cyclosporin A enhanced arsenic trioxide-induced apoptosis in NB4 cells].

OBJECTIVE: To investigate the effects of mitochondrial membrane permeability transition pore (MPT)-opened agent diamide and MPT-closed agent cyclosporin A on arsenic trioxide (As(2)O(3))-induced apoptosis in acute promyelocytic leukemia (APL) cell line NB4. METHODS: NB4 cells were treated with As(2)O(3) alone or in combination with diamide or cyclosporin A in different concentrations. Cell apoptosis was assessed by the morphological observation, Annexin-V assay, distribution of cellular DNA contents and genomic DNA electrophoresis. The mitochondrial transmembrane potentials (DeltaPsim) were detected by flow cytometry according to the intensity of rhodamine 123 uptake in cells. RESULTS: Both diamide and cyclosporin A significantly enhanced As(2)O(3)-induced apoptosis in NB4 cells. The DeltaPsim collapse induced by As(2)O(3) was also enforced by combined treatment with diamide or cyclospo-rin A. 1 micromol/L As(2)O(3) alone treatment for 72 hours led to DeltaPsim disruption in 27.9% of cells, while combined treatment of As(2)O(3) and diamide or cyclosporin A increased DeltaPsim disruption cells to 59.7% and 42.2%, respectively. CONCLUSIONS: As(2)O(3)-induced DeltaPsim disruption possibly involves with thiol oxidation or crosslink of important components especially ANT-related molecules.

Antineoplastic Agents↗
PubMed2002

[High expression of human FIX(hFIX) in transgenic mice directed by goat beta-casein gene promoter].

To probe the feasibility of efficient production of human clotting factor IX(hFIX) with the approach of mammary gland bioreactor of transgenic animals, we constructed hFIX mammary gland expression vector containing promoter, exon 1, intron 1 and exon 2 of the goat beta-casein gene about 6.7 kb fragment as well as full-length of hFIX cDNA and its modified intron 1 sequence. By using transgenic products and 12 transgenic founders (9 female, 3 male) were produced, and the integration rate thus was 11.2%. ELISA assay and Western blot showed that the milk of 8 female transgenic mice had hFIX expression with high clotting activities. The highest hFIX expression in the milk of one transgenic mouse reached 52.9 mg/L, and the highest clotting activity of the transgene milk was 279.2%. FISH experiments indicated that hFIX DNA was integrated in different chromosomes in different mice. This result indicated that the hFIX mammary gland expression vector based on the goat beta-casein promoter can efficiently direct high expression of hFIX gene in the milk of transgenic mice, which maintained high clotting activity.

Animals↗
PubMed2002

[Shape, phenotype and gap junction of the rabbit chondrocytes].

OBJECTIVE: To study the gap junction and phenotype of cultured chondrocyte of rabbit, and the gap junction between the chondrocytes in the same cartilage cavities in human femoral head articular cartilage. METHODS: CFDA-AM was added into the medium of the fifth passage of chondrocyte of rabbit in the 96-well plate. The fluorescent in spherical and fibroblast-like chondrocytes was detected separately. The recurrence of the fluorescent in accordant with time in 16 minutes was recorded after blanching the fluorescent with laser. And the fluorescent after blanching of chondrocyte in the cartilage cavities in the proliferative zone of articular cartilage of adult human femoral head was recorded, too. RESULTS: The average fluorescent of the single layer of the fibroblast-like chondrocyte was 83(ranged from 1 to 274), the highest was found in the spherical shaped cell (averaged 2,057, ranged from 340 to 3,538). The recurrence of the fluorescent after the blanching appeared only in the spherical chondrocyte, the gap junctions reappeared only in the spherical chondrocytes, as well as in the cells in the cartilage cavities in the articular cartilage of the human femoral head. CONCLUSION: The appearance of the gap junction is corresponded with the spherical shape, secretion of the cartilage matrix of the chondrocyte. There are gap junctions in the cells in the same cartilage cavities in the articular cartilage of the human femoral head, while no gap junctions in the isolated chondrocytes in the cartilage.

Animals↗
PubMed2002

[Therapeutic effect of high-density lipoprotein of human plasma on rat endotoxemia].

OBJECTIVE: To investigate the therapeutic effect of high-density lipoprotein (HDL) of human plasma on rat endotoxemia. METHODS: Rats were divided into 2 groups randomly, the treated group received bolus intravenous endotoxin (500 EU/kg), then followed by a bolus HDL (75 mg/kg) intravenously as their blood pressure decreased obviously. The control group just received bolus intravenously endotoxin (500 EU/kg) without HDL. Blood pressure, survival time, the concentration of TNF and the levels of endotoxin in plasma were determined using radioimmunoassay and limulus lysate test. RESULTS: The decrease of blood pressure was obviously attenuated (P < 0.01), the survival time was significantly increased (P < 0.01) and the concentration of plasma TNF was decreased (P < 0.05) in the treated group, compared with those in the control group. The levels of endotoxin were of no significant difference between the two groups (P > 0.05). CONCLUSION: HDL of human plasma has obvious therapeutic effect on rat endotoxemia it could enhance the resistance of rats to endotoxemia, and the mechanism therein may be related to the inhibition of the release of TNF.

Animals↗
PubMed2002

[The study on the stable inheritance and expression of foreign gene in transgenic mice].

Two transgenic mouse strains, in which the expression of human factor IX (hFIX) in the milk were different significantly, were bred, and the foreign gene integration as well as the content of hFIX in the milk were detected by PCR, Southern blot, FISH and ELISA, respectively. The results showed that approximately 50% offsprings were transgenic positive. Foreign gene integrated in mouse chromosomes was intact. The hFIX expression of each mouse in the same strain was different, the content of hFIX in the milk was (43.32 +/- 5.41) microgram/mL in FIX-33 transgenic strain and (1.16 +/- 0.45) microgram/mL in FIX-124 transgenic strain. Meanwhile, the hFIX gene expression between the two strains was different remarkably (P < 0.01). We conclude that the characteristics of inheritance and expression in the founder were able to be transferred to their offsprings stably.

Animals↗
PubMed2002

[Detection of the integration of human FIX (hFIX)on chromosomes of transgenic mice by fluorescence in situ hybridization].

Fluorescence in situ hybridization (FISH) was used to detect the integration of hFIX on chromosomes of transgenic mice from F1 to F4 generation in two strains. For transgenic mice, 98%-100% of metaphases and 85%-94% of interphases showed hybridization signal. For negative control mice,100% of metaphases and 95%-96% of interphases showed no hybridization signal. The results demonstrated that FISH developed to detect the integration sites of hFIX was high efficient and specific. The integration sites of the transgenic mice analyzed were both single but different between the two strains. The integration chromosomes can be found in the transgenic mice from F1 to F4 generation and the integration sites were the same as each of the strains,which indicated that the transgene was stably integrated and transmitted to offspring.

English Abstract↗