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C Li

Publications and source records attributed to C Li.

At least 703 records · Page 39Linked to original sources
PubMed1998

[Observation of inducing effect of five kinds of soft wood dust in micronucleus test].

The authors investigated the micronucleus frequencies (MP) in peripheral lymphocytes in 584 workers exposed to five kinds of soft wood dust and found that all kinds of soft wood dust could increase the micronucleus frequency. As the control's 95% confidential upper limit > or = 0.4% is defined as the standard for positivity the micronucleus positive frequency (MPF) in the exposure group is much higher than that in the control group (P < 0.01). Meanwhile the increase of exposure years may increase the MP, and the time-response relationship is evident (r = 0.90, P < 0.01). For different exposures, the MPFs are: 36.2% for linden, 26.3% for fir. 15.7% for lacebark pine, 9.6% for birch and 2.1% for polar. The positive rate of linden and fir exposure are significantly higher than that of the control group (P < 0.01). Water extract of these five kinds of soft wood dust can increase the frequencies of micronucleus in polychromatic red blood cell in mice's sternum marrow, which also showed a dose-response. The correlation coefficients are: 0.86 for linden 0.6 for fir, 0.39 for lacebark pine, 0.76 for birch and 0.73 for polar. All but the lacebark pine have the P value less than 0.01 (P < 0.01). At the dose of 15 g/kg body weight, micronucleus frequency induced by linden was the highest (0.8%), next were fir (0.71%), birch (0.65%), lacebark pine (0.63%), and polar (0.43%). The results from animal test are consistent with those from the exposure workers. These results suggest that there are some substances in soft wood which can induce chromosome aberration.

Adolescent↗
PubMed1998

[Partially purified antibacterial polypeptides from granules of human large granular lymphocytes].

This was a study on the antibacterial activity of human large granular lymphocytes (LGL). In our previous work, three antibacterial fractions named HLP-1, HLP-2 and HLP-3 had been identified from the acid-soluble extracts of the granules of LGL by using the gel overlay technique. The present study demonstrated that HLP-1, HLP-2 and HLP-3 separated by preparative acid-urea polyacrylamide gel electrophoresis were potently bactericidal against E. coli MI-35P, S. aureus ATCC 25923, P. aeruginosa ATCC 27853 when tested for their antibacteiral activities by using both agarose radial diffusion assay and gel overlay technique. SDS-PAGE analysis showed that the HLP-3 was almost purified with the molecular weight of 7 kd. The HLP-1 and HLP-2 were more complex, and the ranges of molecular weight were 5.6-13 kd and 5.6-8.8 kd respectively. Our study suggests that the granules of human LGL might contain some low molecular weight antibiotic peptides which play an important role in human innate immunity.

Anti-Bacterial Agents↗
PubMed1998

[Comparative study of the third party and paternal leukocyte immunization in recurrent spontaneous abortion of lowered maternal-fetal immuno-recognition].

OBJECTIVE: To compare curative effect of leukocyte immunization to recurrent spontaneous aborters(RSA) with lowered maternal-fetal immuno-recognition between transfusions of the third party leukocyte-rich erythrocyte concentrates and injections of paternal leukocytes. METHODS: Forty RSA patients with lack of blocking antibodies were randomly divided into two groups. Blocking antibodies were analysed by one-way mixed lymphocyte reaction blocking test and complement-dependent cytotoxic test, anti-idiotypic antibodies to blocking antibodies by one-way mixed lymphocyte reaction blocking inhibiting test, and flow cytometry evaluation of blocking antibodies were used to investigate effect of blocking antibodies on the CD antigens of T cells. The immunization was achieved by transfusions of the third party leukocytes or injections of the paternal leukocytes for 3 times or more at an interval of 4 weeks. RESULTS: It was found in dynamical analyses that levels of the blocking antibodies and their anti-idiotypic antibodies increased significantly after the aborters had been immunized. The successful pregnancy rate was 86.2% following immunization, and body weight of the infants was 3,300 +/- 116 g(x +/- s), with no significant difference to 3,279.0 +/- 113.8 g of the infants from normal pregnancy. According to dynamics of blocking antibodies and their anti-idiotypic antibodies, the paternal leukocyte immunotherapy appeared superior to the third party one, but the successful pregnancy rate and the body weight of infants were with not different between the two immunotherapy groups. CONCLUSION: The third party and paternal leukocyte immunization could effectively stimulate the aborters of lowered maternal-fetal immuno-recognition to produce blocking antibodies and their anti-idiotypic antibodies, leading to successful pregnancy. The immunotherapy does not apparently influence the body weight of the delivered infants.

Abortion, Habitual↗
PubMed1998

[Correlation study of spontaneous apoptosis, PCNA, and p53 in esophageal squamous-cell carcinoma].

OBJECTIVE: To investigate the inter-relationships among spontaneous apoptosis, proliferative activity and p53 mutation in esophageal squamous-cell carcinoma. METHODS: In 30 previondy untreated patients with esophageal squamous-cell carcinoma, tissues were examined for apoptosis by in-situ TUNEL, PCNA by immunohistochemistry, p53 mutation by PCR-SSCP and immunohistochemistry. The number of apoptotic cells per 10 low-power microseopic fields was taken as the apoptotic index. RESULTS: Apoptotic index of cells with high proliferative activity was significantly higher than that of cells with low proliferative activity (P < 0.05). In tumors with p53 gene mutation, apoptotic index of cells with high proliferative activity and low proliferative activity was significantly different (P < 0.05). No significant differences were observed in apoptotic index in tumors positive and negative for p53 mutation as examined by PCR-SSCP or immunohistochemistry (P > 0.05). CONCLUSION: In squamous-cell carcinoma of the esophagus, cells with high proliferative activity are apt to undergo spontaneous apoptosis.

Apoptosis↗
PubMed1998

[Bcl-2/JH gene re-arrangement determined by PCR as a means to detect minimal residual disease in malignant lymphomas].

OBJECTIVE: To develop a sensitive method to detect minimal residual disease and to elucidate the significance of bcl-2 gene rearrangement in diagnosis and therapy of malignant lymphoma. METHODS: Using polymerase chain reaction(PCR) to detect bcl-2 gene rearrangement and using serial dilution method to define the sensitivity of PCR. RESULTS: In 9 different malignant lymphoma cell lines, Su-DHL-4 and Su-DHL-6 were shown bcl-2(MBR)/JH rearrangement, the sensitivity of PCR was 1:10(5). In 16 patients with follicular lymphoma, the peripheral blood and bone marrow were PCR positive in 4 both at initial diagnosis and after complete remission. CONCLUSION: Detection of bcl-2 gene rearrangement by PCR provides a sensitive and specific assay of minimal residual disease. It helps improve staging of disease, stratification and evaluation of treatment.

Adult↗
PubMed1998

[The mucosa of pediculed duodenal wall graft transplanted to the stomach in Wistar rats: histological and electronmicroscopic observations].

OBJECTIVE: To study the development mechanism of gastric metaplasia in the duodenum through the transplantation of a flap of duodenal wall with vascular pedicle to the stomach. METHODS: The pedicled duodenal wall flaps of Wistar rats were transplanted to their stomaches. After the operation the rats were killed at the 3th, 6th, 9th and 12th month respectively, and histological change of the duodenal wall grafts was observed with optical and electron microscopy. RESULTS: Gastric metaplasia was found in the mucosa of duodenal wall grafts transplanted to the stomach at the 6th, 9th and 12th month. CONCLUSIONS: The formation of gastric metaplasia in the duodenal mucosa may be related to a change of the microenvironment around the tissues, and duodenal mucosa may differentiate into gastric epithelium by the decrease of pH value.

Animals↗
PubMed1998

[Antifertile effect of immunization with anti-idiotypic antibodies to porcine zona pellucida].

OBJECTIVE: To evaluate the antifertile effect of anti-idiotypic antibodies to PZP. METHODS: The New Zealand rabbits were immunized by 17D3 monoclonal antibody against PZP to produce anti-idiotypic antibodies (Ab2) which were then purified by immuno-affinity chromatography. RESULTS: The mice immunized with Ab2 showed decrease of pregnancy rate and a statistically significant reduction in the number of embryos as compared to controls (P < 0.05). Histological examination of ovaries showed that Ab2 interferes only with late follicular development. CONCLUSIONS: Ab2 to 17D3mAb could alleviate ovarian damage and suppress partial fertility. Clearly, further research is required to screen epitope of inner image of Ab2 and to express it by gene engineering.

Animals↗
PubMed1998

[Hyperinsulinemia and insulin resistance in nondiabetic first-degree relatives of patients in familial NIDDM pedigrees].

OBJECTIVE: To study plasma insulin level and insulin sensitivity of nondiabetic first-degree relatives of patients in familial non-insulin-dependent diabetes mellitus (NIDDM) pedigrees. METHODS: Standard oral glucose tolerance test(OGTT) was conducted in 55 healthy controls and 97 first-degree relatives of NIDDM probands in familial NIDDM pedigrees. Plasma glucose and plasma insulin were determined at all phases after oral glucose load. Moreover, we calculated the glucose/insulin area ratio under the curve of OGTT (SGI) and the insulin sensitivity index (ISI) in all subjects to estimate their insulin sensitivity. RESULTS: In nondiabetic first-degree relatives, SGI and ISI were significantly decreased (P < 0.01), and plasma insulin was increased at 0, 30, 60, 120 minutes after administration of oral glucose load (P < 0.05 and P < 0.01), as compared with the controls, in matched age, body mass index (BMI) and proportion of sex. In both first-degree relatives and the insulin controls, SGI was positively correlated with ISI (r = 0.39, 0.41, respectively, P < 0.01) and both SGI and ISI were inversely correlated with BMI (r = -0.38, -0.39; -0.32, -0.25, respectively, P < 0.01). Moreover, FINS in the two groups was positively correlated with BMI (r = 0.30, 0.34, respectively, P < 0.05). CONCLUSION: In nondiabetic first-degree relatives of patients in familial NIDDM pedigrees, plasma insulin level was increased and insulin sensitivity was decreased as compared with the healthy controls. It suggests that they suffered from hyperinsulinemia and insulin resistance.

Adult↗
PubMed1998

The purification and identification of heme oxygenase isoforms from spleen tissue of rat and the expression of heme oxygenase-1 cDNA in COS-1 cells.

OBJECTIVE: To demonstrate that heme oxygenase (HO) isoforms exist in rat spleen treated with hematin and phenylhydrazine and to confirm that the isolated cDNA actually encodes HO-1 by expressing cDNA in monkey kidney cells (COS-1 cells) in order to prepare HO-1 mutant for inhibiting the natural enzyme. METHODS: The rat spleen microsomal fractions were first purified by diethylaminoethyl (DEAE)-Sephacel and hydroxylapatite. The activity of two isoforms (HO-1 and HO-2) of enzyme and their apparent molecular weight on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (SDS-PAGE) were measured. Secondly, using the isolated HO-1 cDNA clone, the expression plasmid pcDNA3HO1 was constructed and transfected into cultured COS-1 cells. The transfected cells were collected and disrupted by sonication, and the microsomes were prepared by ultracentrifugation. The activity of HO-1 was measured. RESULTS: Two isoforms were purified and identified in treated rat spleen and HO-1 was the predominant form. The ratio of HO-1 to HO-2 was 3.2:1. The apparent molecular weights of HO-1 and HO-2 were about 30 kD and 36 kD under reducing conditions, respectively. The HO-1 was highly expressed in endoplasmic reticulum of transfected cells. The specific band was located in molecular weight of 30 kD. The specific activity was five times higher than that of the control. CONCLUSION: The activity of expressed HO-1 in COS-1 cells is higher than that of purified enzyme from rat spleen tissue. It is suggested that this clone having an insert of 1030 base-pairs encodes HO-1 and that we can prepare HO-1 mutant by site-directed mutagenesis of HO-1 cDNA to prevent and treat hyperbilirubinemia.

Animals↗
PubMed1998

[Outcome of autologous bone marrow transplantation in 73 patients with acute leukemia].

OBJECTIVE: To evaluate the clinical outcome of autologous bone marrow transplantation(ABMT) in acute leukemias. METHODS: Data of 73 acute leukemia patients performed ABMT in our hospital from October 1986 to December 1997 were retrospectively analyzed. The median age was 25.5(9-48) years. Forty-three of them were ANLL [CR1 35, CR2 or early relapse (ER)8], 30 were ALL (CR1 25, CR2 or ER 5). Conditioning regimens were CTX 120 mg/kg + STBI 9-10 Gy or Bu 16 mg/kg or Mel 160-180 mg/m2 + Ara-C 4 g/m2. RESULTS: All patients engrafted successfully. The median follow-up duration was 806 (32-3400) days. The 3-year probabilities of disease-free survival (DFS) for ANLL and ALL in CR1 were 54.9 +/- 7.7% and 67.0% +/- 10.6%, respectively, and the probabilities of relapse were 39.3% +/- 9.3% and 23.7% +/- 10.6%, respectively. CONCLUSION: To decrease relapse and increase DFS, patients with acute leukemia in CR1 who have no HLA-matched related donor are recommended for ABMT.

Adolescent↗
PubMed1998

[The effect of cytokines on the activation of T cells induced by B7-1-transfected leukemia cells].

OBJECTIVE: To observe the effects of IL-12, IFN-gamma, IL-10 on the B7-1 expression of B7-1 transfected leukemia cells (K562 and HL-60) and on the IL-2 and IFN-gamma expression and production in the peripheral blood mononuclear cells(PBMC) induced by B7-1 transfected K562 and HL-60 cells. METHODS: RT-PCR and ELISA techniques were used to assay the expression and production of IFN-gamma and IL-2. RESULTS: IFN-gamma and IL-12 increased the expressions of B7-1, IL-2 and IFN-gamma, but IL-10 inhibited all the expressions. CONCLUSION: IFN-gamma, IL-10 and IL-12 affected the expression and production of IFN-gamma and IL-2 possibly by affecting the B7-1 expression.

B7-1 Antigen↗
PubMed1998

[Influence of fry-processing on outward character and inner quality of volatile oil containing drugs such as fructus Viticis, etc].

According to the requirement of outward character in processing traditional Chinese drugs, five volatile oil containing drugs Fructus Viticis, Rhizoma Atractylodis Macrocephalae, Rhizoma Cyperi, Fructus Foeniculi and Fructus Aurantii were fry-processed. The conditions of frying technology were measured; the amounts of volatile oil before and after processing were determined with accurate volatile oil extractor; and the volatile oil in Rhizoma Atractylodis Macrocephalae and Fructus Aurantii was analyzed by means of GC.

Apiaceae↗
PubMed1998

Bcl-2 gene and its family genes Bax, Bcl-Xl as well as Fas/Apo-1 and their clinical significance in acute leukemia.

OBJECTIVE: To study the suppressing genes of apoptosis, namely Bcl-2, its family genes Bax, Bcl-Xl, and the inducing gene of apoptosis Fas/Apo-1. METHODS: The techniques of cytoimmuno-histiochemical stains, Western blotting and Northern blotting were used. RESULTS: It was found that the antigens of Bcl-2 in acute myelogenous leukemia (AML) and acute lymphocytic (ALL) was higher than that in the normal (P < 0.01). At same time, Bcl-2 was obviously lower expression in complete remission (CR) group than that in non-remission (NR) one by retrospective analysis (P < 0.01). Though Bcl-2 was low expression in CR with Western blotting, there was no statistical significance (P > 0.05). In CR group the expression of Bcl-2 mRNA was obviously lower than that of NR one (P < 0.01). Even though leukemia expression of Bax with cytoimmuno-histiochemical stain was also lower than that in the normal people, there was no difference between CR and NR with cytoimmuno-histiochemical, Western blotting and Northern blotting (P > 0.05). There was difference of Bcl-Xl mRNA in two groups (P < 0.01). The expression Fas/Apo-1 in leukemia was lower than that in normal people (P < 0.01). But in CR and NR, there was no difference with cytoimmuno-histiochemical stain and Western blotting. CONCLUSIONS: The Changes of genes and their proteins are significant theoretically and clinically. The antigen expression of Bcl-2 and the expression of Bcl-2 mRNA may be considered as a prognostic index for AML.

Adaptor Proteins, Signal Transducing↗
PubMed1998

[A simple method of isolation and identification of P cells in rat sinoatrial node].

A method of isolating P cells of rat sinoatrial node by collagenase is described. The method is feasible for morphological and electrophysiological investigation, with the advantages of taking a relatively easy procedure and consuming a small amount of collagenase. The main features of action potentials of these isolated cells including clear diastolic automatic depolarization, mean maximal diastolic potential of -55 mV, mean peak potential value of 58 mV, and mean APD50 of 18 ms, were similar to those of P cells in situ.

Action Potentials↗
PubMed1998

[Simultaneous determination of creatinine, pseudouridine and uric acid in serum and urine by high performance liquid chromatography].

In this paper a sensitive, rapid and simple HPLC method for the simultaneous determination of creatinine (Cr), pseudouridine (Pu) and uric acid(UA) has been established. We have evaluated clinical value of the method in the early diagnosis of diabetic nephropathy (DN). Separation was obtained using Shim-pack CLC-ODS 15 x 0.6 cm column and mobile phase of buffer solution of phosphate (pH 3.0, 0.02 mol/L) with flow rate of 1 mL/min. Detection was performed with UV detector at an automatic adjustment of wavelength. The recoveries of Cr, Pu and UA were 101.4%, 104.9% and 105.0% respectively. The calibration curves were linear within the concentration range of 8.6-274.6 mumol/L for Cr, 0.72-22.93 mumol/L for Pu and 19.1-612.7 mumol/L for UA (n = 6, r > 0.999, p < 0.01). The CV for within day and between day measurements were < 2.5% and < 5.0% respectively. In addition, Pu, Cr and UA were simultaneously determined in serum and urine of 39 patients with diabetic mellitus (DM). 15 patients with nephrotic syndrome (NS) and 53 normal subjects by the method. Results include: 1. the levels of serum Pu in all DM patients (100%) with microalbuminuria (MiAU) and macroalbuminuria (MaAU) were greater than maximum of normal subjects (X + 2S). In addition, in 9 DM patients (41%) with normal albuminuria (NAU) the levels were also greater than the maximum. 2. In patients with DM, there was no correlation between the serum Pu and the urinary albumin excretion (UAE), whereas the serum Pu correlated closely with the serum Cr. However, the incidence for serum Pu increase was significantly greater in patients. 3. The levels of serum Pu in patients with NS were greater than those in control subjects and patients with DM. Conclusion is that the determination of serum Pu could be used as sensitivity index for the early diagnosis of DN.

Chromatography, High Pressure Liquid↗
PubMed1998

[Significance of detecting E-selectin of serum and pleural effusion in differentiating benign and malignant diseases].

OBJECTIVE: To evaluate the significance of detecting E-selectin of serum and pleural effusion in differentiating benign and malignant diseases. METHOD: E-selectin of serum and pleural effusion in 23 patients with tuberculous pleurisy and 21 patients with lung cancer involving pleura was detected by ELISA method. RESULT: E-selectin of serum(44 +/- 5 micrograms/L) and pleural effusion (24 +/- 3 micrograms/L) in patients with tuberculous pleurisy was much higher than that of serum (27 +/- 4 micrograms/L) and pleural effusion (11 +/- 3 micrograms/L) in lung cancer patients (P < 0.01). In addition, E-selection of serum in patients with tuberculous pleurisy was also much higher than that of pleural effusion (P < 0.01). And there was no correlation between E-selectin of serum and that of pleural effusion in patients with tuberculous pleurisy (r = 0.16, P > 0.05). CONCLUSION: E-selectin of serum and pleural effusion in patients with tuberculous pleurisy is produced from different sources. And E-selectin in patients with tuberculous pleurisy is much higher than those with lung cancer. Thence detecting E-selectin of serum and pleural effusion might be helpful for differentiating benign and malignant diseases.

Adult↗
PubMed1998

[Detecting coronary artery disease with dobutamine 99mTc-MIBI myocardial perfusion tomography].

OBJECTIVE: To assess the safety and accuracy of dobutamine stress 99mTc-MIBI perfusion tomography (DST) for detecting coronary artery disease(CAD). METHODS: Seventy nine patients with suspected CAD without previous myocardial infarction underwent DST. Forty eight of the 79 patients had coronary angiography and CAD was defined as greater than 50% reduction in diameter. RESULTS: Seventeen of 20 patients with CAD demonstrated perfusion abnormalities by DST (sensitivity 85%), 20 of 24 with normal or non-significant stenosed coronary arteries had normal scan (specificity 83.3%). All 4 patients with coronary ectasia showed abnormalities by DST. Fifty seven percent of the patients experienced some discomfort, but no serious side effects occurred. CONCLUSIONS: It shows that DST is a safe and accurate alternative to exercise stress perfusion study for detecting CAD in patients unable to perform exercise testing.

Adult↗