Biomedical subjects

J Gao

Publications and source records attributed to J Gao.

At least 109 records · Page 6Linked to original sources

PubMed2001

[Landscape dynamics of two-side lands-along main urban roads in southwestern Shanghai].

Based on the aerial photos of Shanghai in 1984, 1989 and 1994, the landscape databank of southwestern Shanghai was set up. According to the analysis of the landscape dynamics of three two-side belts along the main urban roads in southwestern Shanghai, it was showed that there was a great difference in the landscape succession of these belts with various functions. The main urban roads trended to multi-serving function with the expansion of the city. The change from increase to decrease in the diversity and evenness of landscape and the decline in landscape fragmentation were the major symbols of the landscape dynamics.

China↗

PubMed2001

[Experimental comparison of the adipocytal injuries harvested by three surgical methods].

OBJECTIVE: To evaluate the degree of the injuries on the fat cells harvested by cutting, syringe aspiration and pipe suction techniques. METHODS: Fat tissue was removed from lower abdomen by cutting, syringe aspiration and pipe suction. The excised adipose tissue was cut into 3 mm diameter fat particles, whereas the adipose tissue from syringe aspiration group was taken by the syringe suction technique with No. 22 needle and in the pipe suction group the adipose tissue from the suction tube with 8 mm in diameter. Each sample was fixed in 10% buffered formalin and stained with hematoxylin technique and wilder's silver technique. The fat cells were evaluated under microscope. RESULTS: The percentage of the injured fat cells was (8.6 +/- 1.8)% in cutting technique, (15.7 +/- 2.4)% in syringe aspiration and (76.4 +/- 8.7)% in pipe suction respectively. They had significant differences between each other. CONCLUSIONS: Among the three methods, the degree of the injuries on the fat cells was mostly serious in the way of pipe suction technique while minimal in the way by cutting.

Adipose Tissue↗

PubMed2001

[Human telomerase RNA (hTR) expression in lung cancer in the Gejiu and Xuanwei regions of Yunnan].

OBJECTIVE: To investigate the correlation between the expression of hTR in and the pathogenesis of lung cancer in Gejiu and Xuanwei regions of Yunnan province. METHODS: By use of in situ hybridization, the expression of hTR gene was observed in 81 cases of lung cancer tissues including 24 cases of Gejiu Tin miners (GTM), 36 cases of Xuanwei farmers (XF) and 21 cases of other regions. RESULTS: hTR was detected in 65.4% (53/81) of the lung cancer cases. The positive rate of hTR in GTM, XF and other regions was 66.7% (16/24), 58.3% (21/36) and 76.2% (16/21) respectively. Positive hTR expression was not found in normal bronchial and alveolar epithelia, but was found in highly proliferating type II alveolar epithelial cells adjacent to the carcinoma (12.3%, 10/81). No significant difference was observed with regard to the positive rate of hTR expression among three different regions. There was no statistically significant correlation between the expression of hTR, the patients' sex, age and the differentiation degree of the tumor, but the expression of hTR was correlated with histological type and lymph node metastasis (P < 0.05). CONCLUSION: The expression of hTR is a prevailing event in lung cancer and therefore can be used as an indicator of lung malignancy.

Adult↗

PubMed2001

[A clinical analysis of 112 cases with glucocorticoid glaucoma].

OBJECTIVE: To investigate the etiology, clinical characteristics, treatment and prevention of glucocorticoid glaucoma (GIG). METHODS: Retrospectively, 112 cases (215 eyes) with GIG including 79 males and 33 females in the age range 6-69 years were studied. RESULTS: One hundred and ten cases used glucocorticoid locally, 2 cases used it systemically, and the mean therapeutic time was (27.5 +/- 23.18) months. Conjunctivitis of various causes was the main disease to use glucocorticoid, all 215 eyes had the defect of visual field caused by hypertension, damage of optic disc and retinal nerve fiber layers, just like primary open-angle glaucoma. The degree of injury was related to the therapeutic time. The IOP was decreased after the use of glucocorticoid was stopped, but it could not get to the normal level. There were 162 eyes (75.4%) with characteristic posterior subcapsular cataract and 76 cases combined with myopia. CONCLUSION: The important cause leading to GIG is the abuse of glucocorticoid. The history of using glucocorticoid and the posterior subcapsular cataract are the main bases in the diagnosis and differential diagnosis of GIG.

Adolescent↗

PubMed2001

[The effects of extensive excision of massive invasive infected burn wound on the REE of burn patients with sepsis].

OBJECTIVE: To explore the effects of extensive excision of massive invasive infected burn wound on the REE of burn patients with sepsis. METHODS: REEs and plasma levels of IL -- 6, IL -- 8, TNFalpha and LPS were determined before and after surgical interventions and when patients', condition improved in 8 burned cases with sepsis. RESULTS: All the 8 patients survived after treatment. The REE level in patients after operation was significantly lower than those before the operation (P < 0.01). REE in patients whose condition improved decreased obviously when compared to that after operation (P < 0.01). The plasma levels of IL -- 6, IL -- 8, TNFalpha and LPS decreased markedly after the operation when compared to those before operation (P < 0.05). and there were lower levels of these factors when the patients', condition improved (P < 0.001). Furthermore, there were closely positive correlations between REE and plasma IL -- 6, IL -- 8, TNFalpha and LPS (P < 0.01). CONCLUSION: Over -- releasing of some inflammatory mediators could be corrected by means of extensive excision of massive invasively infected burn wound. This might be beneficial to the control or the amelioration of the hypermetabolism in burn patients with sepsis.

Adolescent↗

PubMed2001

[Prokaryotic expression of hepatitis C virus envelope 1 gene and application of the expressed product].

OBJECTIVE: To express the HCV E1 gene in E. coli cells and to demonstrate its clinical significance in detection of anti-HCV E1 antibodies. METHODS: The expression vector was constructed by ligation of HCV E1 sequence, which was amplified by RT-PCR methods from 50 microliters of HCV RNA positive serum using primers specific to the HCV E1 sequence, to the prokaryotic expression vector PMS-31b transfected POP2136 at 16 degrees C for 16 hours. The recombinant plasmid was screened out and characterized by restriction enzyme analysis. The bacteria containing the recombinant plasmid was induced at 42 degrees C for 4 hours, and the recombinant protein was visualized by SDS-PAGE. The specificity of the recombinant protein was determined by Western blot assay. After purification of the expressed protein, this protein was coated on the plate with the concentration of 2 micrograms/ml in pH 9.6 buffer at 4 degrees C for overnight, and the serum specimen was tested at the dilution of 1:20 by ELISA. RESULTS: There were 2 fragments could be seen on the SDS-PAGE after digestion of the RT-PCR product with Sma I. And there emerged one fragment of 356 bp after digesting the recombinant plasmid with Sma I and Xba I. A band of 30,000 could be seen on the SDS-PAGE after the induction of bacteria containing the recombinant plasmid pMS-E1 at 42 degrees C for 4 hours. The Western blot assay showed that the expressed band could react with the anti-HCV positive serum. The ELISA result indicated that there were 28.9% (26/90) anti-HCV positive serum were anti-HCV E1 positive, but 3.9% (3/76) were positive in the anti-HCV negative serum. CONCLUSION: The HCV E1 sequence from HCV RNA positive serum has been expressed in E. coli. The expression rate is about 17% of the total protein of the bacteria. This protein possessed good specificity and may be used in the diagnosis of HCV infection.

Antibodies, Viral↗

PubMed2001

[Study on quantitative relationship between retention parameters of solutes in reversed-phase liquid chromatography].

A quantitative relationship between lg I (a constant relating to the affinity of one mole of solute to stationary phase) and Z (total moles of organic solvent released at the contact region as one mole solute adsorbed by stationary phase) in the stoichiometric displacement model for retention (SDM-R) of solute was compared with the corresponding relationship in Snyder's Equation in reversed-phase liquid chromatography (RPLC). It was found that the relationship from SDM-R was more exact than that from Snyder's Equation. The linearity depends on the ranges of both lg I and lg Kw0. The broader the range, the better the linearity is. This conclusion conflicts to that reported in references in which the linearity only exists either when one factor dominates solute retention, or when it is completely dominated by statistics. The linear relationship in SDM-R and in Snyder's Equation was found valid not only for homologues but also for non-homologues.

Chromatography, High Pressure Liquid↗

PubMed2001

[Coefficients between TEOAEs and DPOAEs in infants].

OBJECTIVE: To investigate the coefficients of TEOAEs and DPOAEs based on various pass/fail criteria. METHOD: Thirty-six Australia infants were tested (age range: 1-6 months) using both TEOAE and DPOAE. Cohen's Kappa (K) were used to analyze different criteria. RESULT: There is a significant low agreement in the screening outcomes between TEOAEs and DPOAEs, and different criteria for TEOAEs. CONCLUSION: The findings from the study of coefficients among commonly used screening pass/fail criteria suggested that there is no simple relationship among them. The possible reasons for weak agreement were discussed.

Cochlea↗

PubMed2001

[Optimizing the synthesis of hydroxyapatite as a method for the defluoridation of drinking water].

As the cheaper raw materials for the synthesis of hydroxyapatite as a defluoridator, calcium hydroxide and phosphoric acid are used. Hydroxyapatite is made by a hydro-synthesis method, and optimum conditions are determined by batch test for defluoridation with respect to the consumption of phosphoric acid, reaction time and acid-washed product. The results showed that the defluoridation capacity of the synthetic hydroxyapatite for break through (F- 1.0 mg/L is considered as the break through point) was F- 5.6 mg/g in column test, and F- 10.7 mg/g for saturation in column test. After optimization of the synthesis method, the defluoridation capacity of hydroxyapatite is much higher than activated alumina and bone charcoal, which are used currently.

Fluorides↗

PubMed2001

[Determination of arsenic in Chinese herbs by hydride generation atomic absorption spectrometry].

Arsenic in Chinese herbs was determined by Hydride Generation Atomic Absorption Spectrometry (HGAAS). The method was simple and fast, and could be applied to great amount of samples. The detection limit of arsenic was 0.020 mg/kg (dry weight). The recovery and relative standard deviation (RSD) of all samples were 81.5%-125% and 6.2-18.4% respectively. The determined arsenic content of GBW08501 SRM was 82.4%-114.7% of the certified value, and the RSD was 12.6%.

Arsenic↗

PubMed2001

[A study of prognostic factors of stage IV epithelial ovarian cancer].

OBJECTIVE: To determine the effects of treatments for stage IV epidermal ovarian cancer and detect the prognostic factors. METHODS: 31 cases primarily treated in our hospital from 1990 to 1998 were analyzed retrospectively. RESULTS: Univariate analysis showed that the number of courses of chemotherapy, the size of residual disease, the histologic cell type, and the metastatic site were the significant prognostic factors(P < 0.05). Cox proportional hazard model confirmed that two factors (the size of residual lesion < or = 2 cm and the cycles of chemotherapy > or = 8 decreased the death odds ratio by 0.28 and 0.72 respectively. Three factors (lack of operation, presence of supraclavicular lymph node involvement and liver involvement) increased the death odds ratio by 14.25 times, 11.44 times and 1.85 times respectively (P < 0.05). CONCLUSION: Surgical debulking, aggressive and appropriate chemotherapy are important measures to improve survival rate for patients with stage IV epithelial ovarian cancer.

Adult↗

PubMed2001

[Effect on proliferation and apoptosis of human lingual carcinoma cells cotransfected by bax and p53 genes].

OBJECTIVE: To investigate the effects on proliferation and apoptosis of human cancerous cells cotransfected by bax apoptosis-inducing gene and p53 tumor suppressor gene. METHODS: The chimeric gene pSV-CIP-bax-CAT was constructed in which bax gene was flanked upstream by a 217 bp fragment(+822(-)+1093) of the first intron and a 317 bp promoter fragment of human a 1(I) collagen gene. Human lingual carcinoma cell line Tca 8113 (LCC) in culture was respectively transfected with pSV-CIP-bax-CAT, and cotransfected with pSV-p53-CAT and pSV-CIP-bax-CAT by using the transfection reagent DOSPER. RESULTS: Immuno-slot blot and ELISA demonstrated that the expression of bax and p53 genes increased remarkably in the transfected and cotransfected LCC, compared with the controls (LCC transfected with pSV-CIP-CAT and LCC). MTT colorimetric assay, TUNEL fluorenscence microscopy and flow cytometry showed that foreign bax or p53 gene inhibited the LCC growth and induced apoptosis (23.9% and 26.1% of inhibitory rate by bax gene and p53 plus bax genes respectively). CONCLUSION: The ectopic expression of the bax gene in the LCC promoted by the cis-acting elements of human a1 (I)collagen gene has obviously synergistic effect on the proliferation and apoptosis of the LCC contransfected with p53 gene plus bax gene for 48 hours.

Apoptosis↗

PubMed2001

[Synthesis and ultraviolet-visible spectrum of two new symmetrical porphyrins].

Meso-tetra(p-benzoylaminophenyl) porphyrin or meso-tetra (o-benzoylaminophenyl) porphyrin are synthesized by condensation of meso-tetra (p-aminophenyl) porphyrin or meso-tetra (o-aminophenyl) porphyrin and benzoyl chloride in DMF using NaOH as catalyst, these porphyrins and the method have not been reported previously. Their structures are ascertained by elemental analysis, ultraviolet-visible spectrum, IR and 1H-NMR measurements. The ultraviolet-visible spectrum of the two porphyrins is discussed in detail.

Molecular Structure↗

PubMed2000

Strange magnetism and the anapole structure of the proton.

The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange quarks in generating nuclear magnetism. The measurement reported here provides an unambiguous constraint on strange quark contributions to the proton's magnetic moment through the electron-proton weak interaction. We also report evidence for the existence of a parity-violating electromagnetic effect known as the anapole moment of the proton. The proton's anapole moment is not yet well understood theoretically, but it could have important implications for precision weak interaction studies in atomic systems such as cesium.

Journal Article↗

PubMed2000

Cloning and characterization of human VPS35 and mouse Vps35 and mapping of VPS35 to human chromosome 16q13-q21.

Maintenance of different organelles in eukaryotic cells depends on sorting proteins, which ensure the proper delivery of organelle-specific proteins. The studies on yeast (Saccharomyces cerevisiae) VPS35, a hydrophilic membrane protein having a direct role in the retrieval of cargo proteins, suggest a mechanism underlying a possible lysosomal protein-sorting pathway in mammalian cells. Here, we report the isolation of human and mouse VPS35 cDNAs, which are 3208 and 3186 bp in length, respectively. The deduced proteins of the two cDNAs, which are both composed of 796 amino acids and share 99% identity, show homology to yeast VPS35 and other VPS35 homologues of various sources ranging from Schizosaccharomyces pombe to Drosophila melanogaster (31-56% identity and 49-71% similarity), especially in their amino- and carboxyl-termini. The conservation of VPS35 suggests that the function of this class of protein is important. The results of Northern hybridization of human VPS35 in 16 tissues showed that one transcript of 3.6 kb was highly expressed in brain, heart, testis, ovary, small intestine, spleen, skeletal muscle, and placenta and expressed at moderate or low levels in other tissues. Another transcript of 3.0 kb was also expressed with proportionally lower levels than the 3.6-kb transcript in all the tissues except that the 3.0-kb transcript was not detected in brain. Mouse Vps35 was widely expressed as a 3.4-kb transcript. In addition, human VPS35 was assigned to human chromosome 16q13-q21 by radiation hybrid mapping.

Amino Acid Sequence↗

PubMed2000

Parkin functions as an E2-dependent ubiquitin- protein ligase and promotes the degradation of the synaptic vesicle-associated protein, CDCrel-1.

Parkinson's disease is a common neurodegenerative disorder in which familial-linked genes have provided novel insights into the pathogenesis of this disorder. Mutations in Parkin, a ring-finger-containing protein of unknown function, are implicated in the pathogenesis of autosomal recessive familial Parkinson's disease. Here, we show that Parkin binds to the E2 ubiquitin-conjugating human enzyme 8 (UbcH8) through its C-terminal ring-finger. Parkin has ubiquitin-protein ligase activity in the presence of UbcH8. Parkin also ubiquitinates itself and promotes its own degradation. We also identify and show that the synaptic vesicle-associated protein, CDCrel-1, interacts with Parkin through its ring-finger domains. Furthermore, Parkin ubiquitinates and promotes the degradation of CDCrel-1. Familial-linked mutations disrupt the ubiquitin-protein ligase function of Parkin and impair Parkin and CDCrel-1 degradation. These results suggest that Parkin functions as an E3 ubiquitin-protein ligase through its ring domains and that it may control protein levels via ubiquitination. The loss of Parkin's ubiquitin-protein ligase function in familial-linked mutations suggests that this may be the cause of familial autosomal recessive Parkinson's disease.

Amino Acid Sequence↗

PubMed2000

Isoform-specific function and distribution of Na/K pumps in the frog lens epithelium.

Epithelial cells from the anterior and equatorial surfaces of the frog lens were isolated and used the same day for studies of the Na/K ATPase. RNase protection assays showed that all cells express alpha(1)- and alpha(2)-isoforms of the Na/K pump but not the alpha(3)-isoform, however the alpha(2)-isoform dominates in anterior cells whereas the alpha(1)-isoform dominates in equatorial cells. The whole cell patch-clamp technique was used to record functional properties of the Na/K pump current (I(P)), defined as the current specifically inhibited by dihydro-ouabain (DHO). DHO-I(P) blockade data indicate the alpha(1)-isoform has a dissociation constant of 100 microm DHO whereas for the alpha(2)-isoform it is 0.75 microm DHO. Both alpha(1)- and alpha(2)-isoforms are half maximally activated at an intracellular Na(+)-concentration of 9 mm. The alpha(1)-isoform is half maximally activated at an extracellular K(+)-concentration of 3.9 mm whereas for the alpha(2)-isoform, half maximal activation occurs at 0.4 mm. Lastly, transport by the alpha(1)-isoform is inhibited by a drop in extracellular pH, which does not affect transport by the alpha(2)-isoform. Under normal physiological conditions, I(P) in equatorial cells is approximately 0.23 microA/microF, and in anterior cells it is about 0.14 microA/microF. These current densities refer to the area of cell membrane assuming a capacitance of around 1 microF/cm(2). Because cell size and geometry are different at the equatorial vs. anterior surface of the intact lens, we estimate Na/K pump current density per area of lens surface to be around 10 microA/cm(2) at the equator vs. 0.5 microA/cm(2) at the anterior pole.

Amino Acid Sequence↗

PubMed2000

Study on the fluorescence spectra and electrochemical behavior of ZnL2 and Morin with DNA.

The interactions of Morin (2', 3, 4', 5, 7-pentahydroxyflavone) and its Zn-complex, ZnL2.3H2O [L = Morin (2'-OH group deprotonated)], with calf thymus DNA have been studied using fluorimetric and electrochemical methods. ZnL2.3H2O has different spectral characteristics and electrochemical behavior from that of Morin in the presence of DNA. Increasing fluorescence is seen for ZnL2.3H2O with DNA addition whereas decreased fluorescence is observed for Morin. An isosbestic point appears at 560 nm for the DNA-ZnL2.3H2O system with ethidium bromide (EB) addition while no isosbestic point is detectable for Morin. Quenching fluorescence is observed for DNA-EB system when ZnL2.3H2O is added whereas no quenched fluorescence is seen for DNA-EB system with Morin addition. The above results suggest that Morin and ZnL2.3H2O can both bind to DNA, but the binding mode is different. The complex binds to DNA mainly by intercalation, while Morin binds in a non-intercalating mode. The binding constant and binding site sizes are derived from electrochemical methods. For ZnL2.3H2O, the binding constant is 5.0 x 10(4) l mol(-1) at 20 degrees C, and the binding site size n(s) is 5.

DNA↗