Biomedical subjects

H Song

Publications and source records attributed to H Song.

At least 145 records · Page 8Linked to original sources

PubMed1998

Comparison of outcomes of percutaneous mitral valvuloplasty versus mitral valve replacement after resolution of left atrial appendage thrombi by warfarin therapy.

This study assesses the efficacy of oral anticoagulation in resolving left atrial appendage (LAA) thrombi and evaluates clinical outcomes of percutaneous mitral valvuloplasty after resolution of LAA thrombi compared with mitral valve replacement. Warfarin therapy is successful in resolving LAA thrombi; percutaneous mitral valvuloplasty after resolution of LAA thrombi is an effective alternative to surgical treatment.

Aged↗

PubMed1998

IL-1 beta and TNF-alpha suppress apolipoprotein (apo) E secretion and apo A-I expression in HepG2 cells.

The effect of cytokines on apolipoprotein E (apo E) production and secretion was investigated in a human hepatoma cell line HepG2. Incubation of HepG2 cells with interleukin 1 beta (IL-1 beta) or tumour necrosis factor alpha (TNF-alpha) for 48 h resulted in a significant dose-related decrease of apo E concentration in the culture medium, while intracellular apo E content increased without change in mRNA level. In contrast, IL-1 beta and TNF-alpha decreased both intracellular and medium apo A-I. Elution profiles of cholesterol and apolipoproteins revealed that apo E was present in apo E-rich high density lipoprotein (HDL) fraction and apo A-I was in apo E-rich HDL and small HDL fractions. IL-1 beta and TNF-alpha decreased both apo E and apo A-I in these fractions. The present results suggest that IL-1 beta and TNF-alpha suppress hepatic apo A-I expression and secretion but not expression of apo E, which could contribute to the abnormal lipid metabolism in certain cytokine-mediated inflammatory diseases.

Apolipoprotein A-I↗

PubMed1998

Distribution of the receptor for a novel peptide stimulating phosphoinositide hydrolysis in human leukocytes.

OBJECTIVES: Previously we reported that a synthetic peptide, WKYMVm, stimulates phosphoinositide (PI) hydrolysis in several hematopoietic cell lines and human neutrophils. In addition, the peptide induces superoxide generation in human neutrophils. The biochemical stimulation appeared to be mediated by specific receptors on leukocytes. In this report we try to find whether the specific receptor(s) exists on specific types of cells in human leukocytes. DESIGN AND METHODS: To study distribution of the peptide-specific receptors, we prepared a probe, biotin-labeled WKYMVm, and analyzed distribution of the peptide receptor using a biochemical study, cytochemical staining, and flow cytometric analysis. RESULTS: The peptide-specific receptors are expressed in several human leukocytes including granulocytes, monocytes, and B-lymphocytes but not T-lymphocytes and erythrocytes. CONCLUSIONS: These data suggest that the receptors for the peptide restricted to certain types of leukocytes and this specificity is probably related to the specific functions of the stimulated leukocytes.

Amino Acid Sequence↗

PubMed1998

Transcription of the rat p53 gene is induced by a 39kDa protein binding to the p53 promoter region during the liver regeneration.

The adult rat liver is normally in a state of growth arrest. However, cell loss such as partial hepatectomy can induce the proliferation of the hepatocytes. Early after partial hepatectomy, the concentration of p53 mRNA increases during the prereplicative phase. In this study, we identified the cis-regulatory element involved in the induced transcription of the rat p53 gene by DNase I footprinting assay. This element had a partial homology to the AP1 recognition motif, but the competition study with AP1 oligonucleotide showed that this element was not the AP1 recognition motif. The molecular weight of the binding protein to this motif was determined as 39 kDa by southwestern blotting analysis. In vitro transcription assay with the competitor containing the binding motif showed that the 39 kDa protein binding to the element was required for the induced transcription of the rat p53 gene during the liver regeneration.

Animals↗

PubMed1998

Antibody feedback and somatic mutation in B cells: regulation of mutation by immune complexes with IgG antibody.

In response to an appropriate antigenic stimulus, and with help from T lymphocytes, naive B cells differentiate into plasmacytes which produce the primary (germline-encoded) IgM and IgG antibody with low affinity for the antigen. The isotype switch from IgM to IgG coincides with the burst of germinal center reaction and the onset of somatic hypermutation. Here we propose that formation of immune complexes between the residual antigen and the primary IgG antibody, which activate complement and localize specifically in the network of follicular dendritic cells, provides an important signal for triggering the mutation mechanism in germinal center B cells. This hypothesis has been supported by studies on immunogenicity of immune complexes in vivo. The experiments have included an immunization with pre-formed antigen/IgG antibody complex and/or an administration of IgG antibody shortly after the antigen injection. Either of these strategies, which are known to augment the germinal center formation, resulted in earlier onset of somatic mutation and increased mutation frequency in VDJ rearrangements in antigen-reactive B cells, provided that help from T cells was also present. It is presumed that the antigen/antibody/complement complex is able to deliver this important signal by cross-linking of antigen receptor with the CD21/CD19/CD81 molecules on B cells. As a corollary, the signaling by immune complexes may lower the threshold of cell activation determined by receptor affinity for antigen and stimulate diverse V-gene repertoire of B-cell clones in germinal centers.

Animals↗

PubMed1998

Metabolism of benzene, toluene, and xylene hydrocarbons in soil

Enrichment cultures obtained from soil exposed to benzene, toluene, and xylene (BTX) mineralized benzene and toluene but cometabolized only xylene isomers, forming polymeric residues. This observation prompted us to investigate the metabolism of 14C-labeled BTX hydrocarbons in soil, either individually or as mixtures. BTX-supplemented soil was incubated aerobically for up to 4 weeks in a sealed system that automatically replenished any O2 consumed. The decrease in solvent vapors and the production of 14CO2 were monitored. At the conclusion of each experiment, 14C distribution in solvent-extractable polymers, biomass, and humic material was determined, obtaining 14C mass balances of 85 to 98%. BTX compounds were extensively mineralized in soil, regardless of whether they were presented singly or in combinations. No evidence was obtained for the formation of solvent-extractable polymers from xylenes in soil, but 14C distribution in biomass (5 to 10%) and humus (12 to 32%) was unusual for all BTX compounds and especially for toluene and the xylenes. The results suggest that catechol intermediates of BTX degradation are preferentially polymerized into the soil humus and that the methyl substituents of the catechols derived from toluene and especially from xylenes enhance this incorporation. In contrast to inhibitory residues formed from xylene cometabolism in culture, the humus-incorporated xylene residues showed no significant toxicity in the Microtox assay.

Journal Article↗

PubMed1998

Apo A-I and apo E concentrations in cerebrospinal fluids of patients with acute meningitis.

It has been demonstrated that apolipoproteins found in cerebrospinal fluid (CSF) play an important role in lipid metabolism in the central nervous system (CNS). Previously we reported that CSF apo A-I levels increased with the severity of neurological damage in poliovirus-infected macaques. In the present study, apo A-I was quantitatively analysed in CSF from patients with or without neurological diseases. In controls, CSF apo A-I level was significantly higher in males; 3.83 (0.40) mg/L, mean (SEM) (n = 19) compared with females, 2.42 (0.26) mg/L (n = 23, P < 0.05). CSF apo A-I concentrations in patients with acute meningitis increased at the active stage, 7.74 (1.78) mg/L (n = 10), but returned to basal concentrations at the convalescent stage 2.72 (0.38) mg/L (n = 10), while the CSF apo A-I level in patients with other neurological diseases remained in the same range as in controls. By contrast, CSF apo E was consistently elevated at either stage of acute meningitis. Furthermore, it was found that the levels of CSF apo A-I, but not of apo E, correlated positively with CSF albumin concentrations. These findings suggest that the CSF apo A-I and apo E have different origins and may play different roles in the lipoprotein metabolism in CNS.

Acute Disease↗

PubMed1998

Transcription of the rat p53 gene is mediated by factor binding to two recognition motifs of NF1-like protein.

In this study we analyzed the ratp53 promoter by electrophoretic mobility shift assay (EMSA) and DNase I footprinting analysis. As a result we identified two protein binding elements (element 1: -296 to -312, element 2: -195 to -219) with sequence homology to each other. The two identified elements bind to the same kind of protein. To identify the protein binding to these elements, competition assays were carried out with double stranded oligonucleotides containing NF1, YY1, and CRE consensus motifs. Only the NF1 consensus motif competed with element 1 and 2. Element 2 is conserved between the rat, human, and mouse p53 promoters, and has an NF1 consensus motif. However, the sequences of element 1 are comparatively variable between the species. Only the element 1 region of the rat p53 promoter has partial homology to the NF1 consensus motif. This suggests that the element 1 is specific for the rat p53 gene. The molecular mass of the binding protein, determined by Southwestern blotting analysis, was 40 kDa, which is different from that of NF1. In EMSA with an anti-NF1 antibody, DNA-protein complexes were neither supershifted nor decreased. The 40 kDa protein was also detected in rat spleen and lung, but not in kidney. The binding protein was purified by sequence-specific DNA affinity chromatography and it was confirmed that the purified protein binds to the two regions. It was also proved that the identified two elements are required for basal level transcription of the rat p53 gene by in vitro transcription assay.

Animals↗

PubMed1998

[Comparison of partial sequencing of 5' non-coding region of seven HGV strains isolated from different areas in China].

OBJECTIVE: To explore the variation of Chinese hepatitis G virus (HGV) strains. METHODS: HGV RNA was detected by reverse transcription nested polymerase chain reaction (RT-nPCR) with a designed primer derived from the 5' non-coding region of Chinese HGV strains. HGV cDNA was sequenced in seven samples with positive products by ABI prism 377 DNA automatic sequencer. RESULTS: Homology of nucleotide sequence of the 5' non-coding region of HGV strains in seven Chinese strains was 88.26%, 85.92%, 88.26%, 85.45%, 86.85%, 85.92% and 88.26%, respectively, as compared with the African strains GBV-C (u 36380), and 92.02%, 86.85%, 86.67%, 89.02%, 89.67%, 89.67% and 91.55%, respectively, as compared with the strains isolated from the U.S. (u 44402). Homology of nucleotide sequence was 92.02% to 97.18% between HGV strains isolated in China. CONCLUSION: Genotypes of Chinese HGV strains differ from those of GBV-C and HGV subtypes reported in the U.S.

5' Untranslated Regions↗

PubMed1998

[Studies on hygienic standard for ozone in indoor air].

OBJECTIVE: To formulate a national hygienic standard for ozone in indoor air. METHODS: Indoor air ozone concentrations at variety of places were detected at its peak level in the daytime. Also, animal experiments exposed to low-level ozone were conducted to study the contents of lipid peroxide in the lungs, the ultrastructure of the bronchial epithelium and the phagocyte function of peritoneal macrophage. RESULTS: Safety of ozone concentration of 0.1 mg/m3 in indoor air and feasibility to use it as hygienic standard were tested and proved. CONCLUSION: The national hygienic standard for ozone in indoor air is recommended at 0.1 mg/m3 based on the data and relevant criteria at home and abroad.

Air Pollution, Indoor↗

PubMed1998

[Comparative study on the retention effect of the inhaled mineral and coal dusts in rat lung].

The pulmonary retention and physico-chemical characteristics of the dust are very important factors in the occurrence of pneumoconiosis. This paper reports a comparative study on the retention characteristics between the inhaled mineral dust and coal dust in rat lung. The dust quantities in the lungs and the mediastinal lymphatic nodes were determined by the formic acid digestion method. The results showed that the pulmonary retention quantities of the coal dust in rats were higher than those of the mineral dust on the third day but lower on the 90th day after exposure for two weeks. The results suggest that the mineral dust can deposit in the lung longer than the coal dust, and the lymphatic system is important for the pulmonary elimination of the dust.

Animals↗

PubMed1998

[Effects of low concentration ozone on the respiratory system of mice].

Effects of low concentration of O3 on the respiratory system in mice were studied in the present study. Mice were exposed to 0.1, 0.25 and 1.0 mg/m3 of O3, respectively for 8 h per day for 3 days. Cilia in brochia, Lipid peroxide (LPO) in lung tissue and phagocytic function of macrophage in mice were examined. The results showed that there were cilia damage in the 1.0 mg/m3 group and swelling of mitochondrias as well as endoplasmic reticulums in the 0.25 mg/m3 group. But no damage was found in the group of 0.1 mg/m3. Furthermore, phagocytic rates in the 0.25 and 1.0 mg/m3 groups were significantly lower than that of control group (P < 0.01). No differences in LPO leads were found.

Animals↗

PubMed1998

[Investigation of the Zeta reference values by Chinese-built Zetafuge and preliminary application].

We determined the Zeta sedimentation ratio (ZSR) for 326 normal subjects and 106 inpatients by Chinese-built Zetafuge. The mean ZSR for normal subjces was 52.5 +/- 5.05% and that for inpatients 68.52 +/- 5.54% (P < 0.001). ZSR can be determined by using directly the blood sample with the anticoagulant EDTA-K2; the determination is faster and requires less volume of blood sample; it is not affected by anemia and need not be corrected for age and sex. The results of ZSR are expressed in a new unit, %, not in mm/h. The reference value we established is: < or = 62%. We also discussed the problem of reproducibility, the speed of centrifuge, the height of blood, and compared this method with the westergren method. The agreement between the two methods is 86.6%.

Adult↗

PubMed1998

[Bcl-2 gene expression in endometrial carcinoma].

OBJECTIVE: To evaluate the relationship between bcl-2 gene and endometrial carcinoma. METHODS: Immunohistochemical staining was performed on formalin-fixed paraffin-embedded tissue sections. A monoclonal antibody to the bcl-2 gene product was used, the signal was detected using a streptavidin-biotin complex with aminoethylcarbazole. There were 15 cases of endometrial atypical hyperplasia and 50 cases of endometrial carcinoma examined. RESULTS: Bcl-2 expression was high in endometrial atypical hyperplasia, whereas bcl-2 expression was low in endometrial carcinoma. In endometrial carcinoma, with progression of clinical stage, decreased histologic grade and deepening of cancer invasion, the positive rate of bcl-2 expression was correspondingly decreased. CONCLUSION: Bcl-2 plays a role in the genesis of endometrial carcinoma especially at the initial stage.

Adult↗

PubMed1998

Pregnancy outcome of patients conceiving within one year after chemotherapy for gestational trophoblastic tumor: a clinical report of 22 cases.

OBJECTIVE: To determine the risk of pregnancy for patients who conceive within one year after successful chemotherapy for gestational trophoblastic tumor (GTT). METHODS: We followed up and analysed retrospectively 22 patients who conceived within one year after receiving chemotherapy for GTT from 1966 through 1996. RESULTS: Of 22 patients, 9 had term delivery, 1 had premature birth, 6 requested induced abortion, and 6 experienced therapeutic abortion because of repeated hydatidiform mole (1 patient), intrauterine death (1), inevitable abortion (1), or threatened abortion (3). The fetal wastage rate was 27.3% (6/22). The incidence of gestational trophoblastic disease (GTD), including hydatidiform mole, was 9.1% (2/22). The incidence of GTT was 4.5%. The average interval between completion of chemotherapy and pregnancy was 9.78 months in the group of term pregnancy and 6.50 months in the group of fetal wastage (P < 0.05). CONCLUSIONS: Patients conceiving within one year after successful chemotherapy for GTT are at higher risk for recurrence of GTD and fetal wastage. Therefore, patients with preserved fertility should practice contraception for at least one year after chemotherapy to get better pregnancy outcome.

Abortion, Threatened↗

PubMed1998

[Observation on inhibitory effect of Coptis alone and its combination with Scutellaria and Liquorice on the growth of Staphylococcus aureus].

Using MIC as relative index, an observation was made on the growth inhibition of Staphylococcus aureus by Coptis alone or in combination with Scutellaria and or liquorice. The result shows that when Coptis is combined with Scutellaria, the bacteriostatic effect gets weaker for Scutellaria, but remains unchanged for Coptis, and when Scutellaria takes greater percentages in the combination, the effect of Coptis seems to be stronger. When Coptis is combined with liquorice, whatever the respective percentages may be, the effect tends to get weaker. When the three drugs are used in combination, the effect remains unchanged or even gets stronger for Coptis or liquorice, but tends to decrease for Scutellaria. Coptis used singly or in combination with Scutellaria or liquorice is inferior in bacteriostatic effect to the combination of the three drugs. The mechanism is yet to be further studied.

Drug Combinations↗

PubMed1998

A comparative study of transvaginal ultrasonography and pelvic arteriogram in assessment of patients with gestational trophoblastic tumour.

OBJECTIVE: To compare the reliability of transvaginal ultrasonography with pelvic arteriography in the assessment of patients with gestational trophoblastic disease. METHODS: Transvaginal ultrasonography was performed in 24 patients with gestational trophoblastic tumour. Within one week after ultrasound investigation, pelvic arteriography was carried out in each patient. Of 24 cases, 16 patients hadn't been treated by chemical reagent, 5 had accepted 2 to 5 courses of chemotherapy, and 3 had achieved complete remission before both investigations performed. RESULTS: In 3 patients with complete remission, 2 had no evidence of abnormal findings either on transvaginal ultrasonography or on pelvic arteriography, 1 showed intramyometrial lesions by both methods. In the remaining 21 patients, all demonstrated a abnormal uterine image, and 5 of them accompanied with the finding of parametrium metastatic signs by transvaginal ultrasonography; these abnormal results were confirmed by pelvic arteriographic imaging. However, in two cases without clinical and ultrasonic signs of parametrium metastasis, pelvic arteriography indicated the early metastasis of parametrium vessels. CONCLUSIONS: Even though it is difficult to predict the early parametrium metastasis in patients with gestational trophoblastic disease by B-ultrasonic investigation, our data would support the introduction of transvaginal ultrasonography in the diagnosis and evaluation of gestational trophoblastic tumour.

Angiography↗

PubMed1998

[Long-term results of combined splenorenal shunt and porta-azygos devascularization in patients with portal hypertension].

OBJECTIVE: To investigate the long-term effects of combined splenorenal shunt and porta-azygos devascularization in patients with portal hypertension. METHOD: We analysed retrospectively the follow-up results of 140 portal hypertensive patients undergoing the combined therapy in our hospital from April 1978 to April 1997. Changes of portal hemodynamics were studied by Doppler Flowmeter and DSA pre- and-postoperatively and direct FPP measurement intraoperatively. RESULT: The operative mortality was 3.6%. No rebleeding was noted in a short period and rebleeding rate was 8.3% in a long term follow-up. The rate of postoperative hepatic encephalopathy was 5.0%. The long-term survival rate of 5-, 10- and 15-years was 83.6%, 64.5% and 54.5%, respectively. After operation FPP and PVP decreased significantly (P < 0.01) and FPP maintained at the level of 3.2 +/- 0.4 kPa. CONCLUSION: The combined procedure is a rational and practical procedure for the treatment of patients with portal hypertension.

Adolescent↗