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G Huang

Publications and source records attributed to G Huang.

At least 163 records · Page 9Linked to original sources
PubMed1997

[Ten-year experiences of epiglottic laryngoplasty after partial laryngectomy].

In order to objectively evaluate the long-term result of epiglottic laryngoplasty (ELP), ten-year experience of ELP after partial laryngectomy in 100 patients with glottic cancer was analysed. Our program included 1. complete excision of laryngeal carcinoma; 2. correct selection of material for laryngoplasty (LP); 3. technical modification of LP. The 3, 5 and 10 year survival rates were 87%, 79.5% and 66.7% respectively. It is believed that modified ELP is better than original K-S-T technique in the aspect of preserving all laryngeal functions.

Adult↗
PubMed1997

[Immunohistochemical study on myoglobin in electrocution].

We have studied the changes of myoglobin (MB) IN heart muscle cells from eight corpses died of electrocution. The changes were compared with that of the heart muscle cells died of fall. The results indicated that the immunohistochemical changes of Mb were as follows: (1) blocky separate from heart muscle cell; (2) drift away into the interval of the heart muscle. The Mb changes were small parts of an area separate from heart muscle cells in control. The authors emphasized these changes were the characteristics of oxygen deficiency of the heart by electrocution.

Adolescent↗
PubMed1997

[Rapidly expanded skin tube studied by histological and stereological observations].

In order to investigate the histological and stereological change of the rapidly expanded skin tube, 15 Japanese Long Ear Rabbits were divided into 3 groups: (1) Rapid expansion group, injecting once a day for 7 days; (2) Routine expansion group, injecting every 3 days for 21 days and (3) Control group, no expander implanted. The results showed that: in the rapid expansion group, the thickness of the epidermis and dermis were both increased, fibroblast proliferation was active, a large amount of new capillaries was observed, the collagen fiber was in loose type, and the mitochondria and rough endoplasmic net of epithelial cell were increased. In the routine expansion group, similar changes were observed. The vascular density and volume fraction were significantly higher in rapid expansion group than those in the control group (P < 0.05). It was concluded that the rapid expansion of skin tube was feasible.

Animals↗
PubMed1996

Future potential of targeted component analysis by multidimensional liquid chromatography-mass spectrometry.

Multidimensional liquid chromatography (MDLC) may be used in either (i) the profiling mode where it is the objective to fractionate all components in a mixture or (ii) the targeted component mode in which it is the objective to determine specific analytes. This paper focuses on targeted component analysis from complex mixtures, addressing the critical operations of analyte selection and transport from the first to the second dimension. Although the physical operation of switching a component into the second dimension with computer controlled valving is simple, it is shown that changes in analyte retention time and peak width with column age and fouling are a serious problem. The analyte moves out of the preselected time window for valve switching and quantitation is compromised in the second dimension. It is proposed that a solution to the "drifting peak" phenomenon in targeted component analysis is to use binary mobility elution in the first dimension. Binary mobility refers to those systems, such as affinity chromatography, in which analyte mobility is generally either 0 or 1 relative to mobile phase velocity. Coupling these binary changes in analyte mobility in the first dimension with valve switching eliminates the "drifting peak" phenomenon. In addition, it is shown that a wide time window may be used in affinity separations without compromising the separation or accumulating contaminants. Several cases are described in which immunosorbents were used with reversed phase columns to provide quantitative targeted component analyses from complex mixtures.

Animals↗
PubMed1996

Affinity maturation without germinal centres in lymphotoxin-alpha-deficient mice.

Affinity maturation by somatic hypermutation is thought to occur within germinal centres. Mice deficient in lymphotoxin-alpha (LT alpha-/- mice) have no lymph nodes or Peyer's patches, and fail to form germinal centres in the spleen. We tested whether germinal centres are essential for maturation of antibody responses to T-cell-dependent antigens. LT alpha-/- mice immunized with low doses of (4-hydroxy-3-nitrophenyl)acetyl-ovalbumin (NP-OVA) showed dramatically impaired production of high-affinity anti-NP IgG1. However, LT alpha-/- mice immunized with high doses of NP-OVA, even though they failed to produce germinal centres, manifested a high-affinity anti-NP IgG1 response similar to wild-type mice. Furthermore, when LT alpha-/- mice were multiply immunized with high doses of NP-OVA, the predominantly expressed anti-NP VH gene segment VH186.2 showed somatic mutations typical of affinity maturation. Thus, B-cell memory and affinity maturation are not absolutely dependent on the presence of germinal centres.

Amino Acid Sequence↗
PubMed1996

Expression and localization of inhibin/activin and activin receptors in GH3 cells, a rat pituitary adenocarcinoma cell line.

Inhibins and activins are members of the transforming growth factor beta (TGF beta) superfamily. Since TGF beta has been shown to be a potent proliferation-inhibiting agent for the pituitary adenocarcinoma cell line, GH3, we determined whether this cell line (a) transcribes mRNAs coding for inhibin/activin subunits (alpha and beta A) and activin receptors I, II, and IIB; and (b) produces inhibin and/or activin proteins. Messenger RNAs for the alpha- and beta A-subunits of inhibin and activin receptors I, II, and IIB in GH3 cells were detected and localized using the reverse transcription-polymerase chain reaction (RT-PCR) analysis and in situ hybridization, respectively. The identity of the RT-PCR products was confirmed by DNA sequencing of PCR products. Immunocytochemically, inhibin and activin were localized in these cells. Our findings indicate that messenger RNAs encoding inhibin alpha- and beta A-subunits and activin receptors I, II, and IIB were expressed, and inhibin/activin proteins were produced, by GH3 cells, imply that these gonadal growth factors may have paracrine/autocrine functions in rat pituitary adenocarcinoma. Further, these observation suggest that these growth factors may be involved in regulating the growth and differentiational of rat pituitary adenocarcinoma cells.

Activin Receptors↗
PubMed1996

Binding of antithyrotropin receptor autoantibodies in Graves' disease serum to nascent, in vitro translated thyrotropin receptor: ability to map epitopes recognized by antibodies.

The binding of Graves' disease autoantibodies and xenogeneic antibodies to the human TSH receptor (TSH-R) has been studied using receptor preparations generated in an in vitro transcription and translation reaction. The complementary DNAs encoding for the full-length (764 amino acids) and the extracellular region of TSH-R (amino acids 20-414, lacking the signal sequence) were used to generate the translated receptor antigen. Stable [35S]methionine-labeled nascent protein for full-length and extracellular regions of TSH-R of approximate size 87 and 50 kDa, respectively, together with other smaller proteins were generated. The 87- and 50-kDa translated receptor proteins react by immunoprecipitation analysis with monoclonal antibodies, polyclonal antisera, and unfractionated Graves' disease serum containing autoantibody to TSH-R. The translated products of the extracellular TSH-R were examined in detail. Using three well characterized murine monoclonal antibodies whose epitopes encompass the amino-, central, and carboxyl-terminals of the extracellular region of the receptor led to immunochemical identification of the smaller translated products to derive from internal methionine start sites of TSH-R. These smaller, N-terminal-truncated translated proteins were also recognized by polyclonal antisera generated against recombinant TSH-R, thus allowing epitope mapping of some antibodies. A large proportion of Graves' disease autoantibodies (> 70%) bind to the translated extracellular region of TSH-R. This indicates that the majority of pathogenic anti-TSH-R autoantibody binds the nascent translated extracellular region of TSH-R, which is not influenced by the lack of glycosylation of the receptor.

Animals↗
PubMed1996

Prognostic significance of lymph node metastasis in surgical resection of esophageal cancer.

OBJECTIVE: Although surgery is relatively successful in eradicating local tumor, post-resection five-year survival rate for esophageal cancer is still lower than 30%. Multiple factors are found to influence the long-term results after surgical treatment. However, recent investigations have focused on the significance of lymph node matastasis (LNM), which seems to be one of the most important factors leading to poor survival. Hence, the prognostic significance of LNM in surgical resection of esophageal cancer was studied. METHODS: The rate and degree of LNM were evaluated and their prognostic significance was investigated through a retrospective study of 474 patients with esophageal cancer treated by surgery alone. RESULTS: LNM was positive in 211 patients, with an incidence of 44.5% (211/474). A total of 5382 lymph nodes were resected and studied pathologically, among which metastasis was found in 690 nodes with an overall LNM degree of 12.8% (690/5382). The 5-year survival rate was 30.6% (145/474) in the entire series, 12.8% (27/211) in patients with LNM, and 44.9% (118/263) in those without LNM. CONCLUSIONS: Surgery remains the first choice of treatment for carcinoma of the esophagus, and that meticulous lymph node dissection is an important practice of surgical oncology. However, in more advanced cases of this disease, surgery alone is of limited value in eradicating all cancer compromized tissue, and therefore the routine practice of extensive lymph node dissection in such cases may not be rewarding.

Adult↗
PubMed1996

[Modulation of bcl-2 antisense RNA on programmed cell death of leukemic cell line].

OBJECTIVE: To investigate modulation of decrease of intrinsic bcl-2 protein levels on programmed cell death of leukemia cells. METHOD: Gene transfection procedure was applied to observe the effect of antisense RNA-mediated suppression of bcl-2 gene expression on programmed cell death of human T-lymphocytic leukemia cell line CEM. RESULTS: Temporary expression of antisense bcl-2 gene could effectively reduce levels of intrinsic bcl-2 protein of CEM cells and render it more sensitive to etoposide-induced cytotoxicity. Moreover, a great deal of apoptotic bodies and ladder DNA was always produced during etoposide-mediated killing of CEM and when CEM expressing bcl-2 antisense RNA served as target cells in particular, the amount of ladder DNA increased to around 40%. CONCLUSION: Programmed cell death is one of the mechanisms by which etoposide kills leukemic cells and is modulated by cellular intrinsic bcl-2 protein.

Antineoplastic Agents, Phytogenic↗
PubMed1996

[Carcinogenic mechanisms of multiple genes in cervical carcinoma].

The alterations of multiple genes and their carcinogenic mechanism in cervical carcinoma were studies by molecular hybridisation, PCR and PCR-ASO techniques. The G-T point mutation in the 12th coden of Ha-ras was detected in cervical carcinomas with mutation frequency of 18.2% (8/44), and the amplification rate of Ha-ras gene was 45% (9/20). The c-erb B2 was amplified 3-30 fold with an amplification rate of 73.3% (11/15) in cervical carcinomas and 5 cancerous samples showed gene rearrangement. The elevated copies of c-myc gene with amplification rate of 91.7% (11/12) were observed in cervical carcinomas. The study of HPV16 viral gene showed that the existence of HPV16 DNA sequence was positively associated with c-myc gene amplification in cervical cancerous samples. The p53 and Rb tumor suppressor genes absence of deletion were observed in the 12 specimens of cervical carcinoma investigated. As mentioned above, the study on alteration and carcinogenic mechanism of multiple genes indicated that 3 oncogenes and HPV16 viral gene were activated or integrated throygh different mechanisms and they played roles in co-carcinogenesis. The integration of HPV16 gene might promote the c-myc gene at the early stage in carcinogenesis of cervical carcinoma, while the alteration of Ha-ras and c-erb B2 gene might be middle-late event. As for the roles of the p53 and Rb tumor suppresor gene in cervical carcinogenesis need further researches.

Carcinoma, Squamous Cell↗
PubMed1996

[Relationship between the express product of src gene (pp60c-src) and the initiation of gastric carcinoma].

The tissues of the fetal gastric epithelia, adult normal gastric epithelia, gastric epithelial lesions, gastric carcinoma and the tissues adjacent to carcinoma were studied immunohistochemically by using the specific monoclonal antibody of c-src gene express product (pp60c-src), MAb 327. The positive rates of pp60c-src in the fetal gastric epithelia, adult gastric epithelial inflammatory hyperplasia, intestinal glandular metaplastia and gastric carcinoma were 100.0% (12/12), 100.0% (30/30), 100.0% (16/16), 83.3% (40/48), respectively, all these pp60c-src positive rates were higher than that of adult normal gastric epithelia (60.0%, 12/20), a significant difference was noted statistically (P < 0.005). And there was statistical significant difference of pp60c-src express amount among different tissues (P < 0.005). The positive rates of pp60c-src in the intestinal and diffuse type gastric carcinomans were 100.0% (16/16) and 68.8% (22/32), respectively, a significant difference was found statistically (P < 0.025), the difference of pp60c-src express amount was significant (P < 0.05) but no significant differences of the positive rates and express amount of pp60c-src in the tissues adjacent to carcinoma of two types of carcinoma were found (P > 0.05). The results of this experiment indicated that the activation of c-src gene and increase of pp60c-src express were associated with the proliferation, turnover, transformation and malignant change of the gastric epithelial cells, with the initiation of the gastric carcinoma, and also with the differentiation and the histological types of the gastric carcinoma.

Adenocarcinoma↗
PubMed1996

[Exploration of certain factors affecting the airway resistance and its determination with interruption technique for normal old, middle-aged and young persons].

The airway resistance (Raw) was determined with interruption technique for 327 normal old, middle-aged and young persons after exploration of the effect of forced respiration, lung volume and upper airway compliance on it. FVC, V75, V50 and V25 were also performed. The regression equations of expiratory and inspiratory resistances (R. R1) were built with age, height and FVC as independent variables. The results showed that both expiratory and inspiratory resistances had a tendency of increase with aging, and FVC, V75, V50, V25 were declined with aging. This reflected that various organs and tissues including respiratory organs gradually oldened with aging. The decrease of elastic recoil of lung and central airway can lead to an increase of airway resistance in various degrees or no change. The data and regression equations can be recommended for the application in public health and clinical care.

Adult↗