To construct an eukaryotic expressing vector that expresses CH50, a recombinant Cell I-Hep I bifunctional-domain polypeptide of human fibronectin, and to investigate the chemotaxis to immune cells and the inhibitory effect on the growth of tumor by the expression of the plasmidin vivo, the plasmid was constructed by DNA recombination. Gene transfection was performedin vitro andin vivo. The expressed product was identified by Western blot. The chemotaxis after gene transfectionin vivo was observed by histotomy and staining of muscle tissues. The inhibition of gene transfection on solid tumor was observed in mice. The results showed that plasmid pCH510 was constructed by the recombination of the 5′-terminal noncoding region and signal peptide coding region of human fibronectin cDNA and cDNA fragment coding CH50 polypeptide with a 3′-terminal noncoding region of human FN cDNA, and the insertion of the recombinated fragment into plasmid pcDNA3. 1. After transfection with plasmid pCH510, NIH3T3 cells could produce CH50 polypeptide. The transfection of plasmid pCH510 by the injection in muscle of mouse could produce the effects of chemotaxis on immune cells and the inhibition on the growth of solid tumor. It is concluded that plasmid pCH510 can express in cells andin vivo in mouse. The expression of the plasmidin vivo has a chemotactic effect on immune cells and can inhibit the growth of solid tumor.

Plasminogen activator inhibitor 1 (PAI-1) is one of important coagulant factors. Endotoxin lipopolysaccharide (LPS) induces thrombosis by stimulating PAI-1 secretion of vascular cells (EC). Using sandwich enzyme-linked immunosorbent assay (ELISA) and Northern blot, was investigated the effects of Chinese medicine ligustrazini on PAI-1 expression in EC and LPS-stimulated EC. The results showed that ligustrazini inhibited both basal and LPS-induced PAI-1 mRNA expression in EC. The effect of ligustrazini on LPS-induced PAI-1 secretion worked in a dose-dependent manner. This study provided theoretic and experimental evidence for use of ligustrazini against septic shock and cardiovascular diseases.

In order to assess the impact of mRNA degradation on steady state levels of follicle-stimulating hormone receptor (FSHR) mRNA and on regulation of FSHR gene expression, the stability and half-life of FSHR mRNA were determined in transfected cells expressing recombinant FSHR. Time-dependent changes in FSHR mRNA content were determined by nuclease protection-solution hybridization assay (NPA) or by qualitative reverse transcription-competitive polymerase chain reaction (RT-PCR) in cultured hFSHR-YI cells, cell lines stably transfected with a human FSHR cD-NA. FSHR mRNA content remained constant during 8 h control incubations of hFSHR-YI cells (NPA, 2. 9±0. 3 μg/mg RNA; RT-PCR, 2. 7±0. 3 μg/mg RNA). Actinomycin D (ActD, 5 μg/ ml) inhibited mRNA synthesis, as assessed by incorporation of [³H]uridine into total RNA, by 90 % within 1 h in hFSHR-Y1 cells. No effect of ActD on cellular morphology or viability was observed. ActD caused a time-dependent decrease in FSHR mRNA content in hFSHR-Y1 cell lines with a lag time of 1 h. There were no significant differences in the rate of FSHR mRNA degradation between the two methods of mRNA quantification. The half-life of hFSHR mRNA was 3. 6±0. 2 h by NPA and 3. l±0. 1 h by RT-PCR. The results indicated that degradation of mRNA was an important process in maintenance of steady state expression of the FSHR gene in cells stably expressing recombinant receptor.

Four phthalocyanines (iron tetracarboxylphthalocyanine, copper tetracarboxylphthalocyanine, manganese tetracarboxylphthalocyanine, cobalt tetracarboxylphthalocyanine) were used as dual functional mimic enzymes of Superoxide dismutase (SOD) and catalase (CAT). The first function, eliminating O₂^-, was proved by using riboflavine-methionine photoreduction method in the concentration range of 10^-5 to 10^-6 mol/L. The second function, clearing out H₂O₂, was demonstrated by means of spectrophotometry with the decomposing percentage being increased with the increase of the concentration of the imitating compounds. Measurements of metal phthalocyanines, SOD and CAT by the liver homogenate technique of mice showed that they had obvious action of decreasing the lipid peroxidation.

The relationship between hyperhomocysteinemia and coronary artery disease (CAD) was investigated and the influence of environmental factors (Folate, VitB12) and genetic factors [N5, N10-methylenetetrahydrofolate reductase gene (MTHFR) or MTHFR gene mutation] on plasma homocysteine (Hcy) levels and the risk of CAD observed. Fifty-one CAD patients and 30 CAD-free subjects were recruited in the study. The polymorphisms of MTHFR gene were analyzed by PCR-RFLP and plasma total Hcy levels were measured by high performance liquid chromatography with fluorescence detection. Plasma folate and vitamin B12 concentrations were measured by an automated chemiluminescence method. It was found that mean total plasma Hcy concentrations were significantly higher in CAD patients than in CAD-free subjects (P<0. 01). The differences were also apparent among the three genotypes of MTHFR gene in CAD group (P<0. 05). There was no significant difference in the genotype distributions and allele frequencies between the two groups. A strong inverse correlation was found between folate or vitamin B12 and plasma Hcy levels according to MTHFR genotype (P<0. 01). It was concluded that hyperhomocysteinemia is a new independent risk factor for CAD. However, MTHFR gene mutation alone does not relate significantly to the morbidity of CAD since hyperhomocysteinemia and its influence on the risk of CAD are decided by both environmental and genetic factors. Supplementary treatment with vitamins B can effectively lower the plasma levels of Hcy, thus maybe reduceing the risk of CAD.

During last 16 years we have successfully developed the computer-assisted vectorcardiogram analysis systems: model TJ-I. TJ-I, and TJ-I, but some technical problems remained unresolved, such as the recognition accuracy for vectorcardiograms, measurement of the parameters of complicated QRS waves, the ratio of T loop length to width, and the area of spatial vectors etc. A new system, model TJ-IV was designed to resolve these technical problems. The system was equipped with a 586 computer with a CPU of 120 MHz. Special new low-noise amplifier was employed and C language was used for programming. Three graph recognition techniques were used to enhance the accuracy of VCG recognition. 32 orthogonal electrocardiograms and vectorcardiograms were displayed and printed, and 566 parameters of vectorcardiograms were calculated. Our results with 150 cases showed that the system had high accuracy of graph recognition, and parameter calculation and the results were essentially consistent with those of manipulative methods. We were led to concluded when compared with TJ-I system, the new version has higher accuracy of processing and measurement for vectorcardiograms, is able to process more vectorcardiographic parameters, with higher processing speed.

In order to improve the efficacy of modified inferior method or middle method of radiofrequency catheter ablation (RFCA) in the treatment of atrioventricular node reentrant tachycardia (AVNRT), the clinical data of 325 cases of AVNRT from March 1992 to Feb. 2000 being subjected to the treatment of RFCA were retrospectively analyzed. The results showed that the successful rate was increased and recurrence was decreased year by year. In the recent 4 years the effective rate was up to 100%. The complication of three grade of AVB occurred in 3 % and recurrent rate in 9. 1 % before March 1996, but both of them were zero in the last 3 years. The time of RFCA procedure and X-ray exposure was significantly reduced. It was concluded that ablating more than 3 targets by modified inferior method or middle method with energy titrating and strict endpoint was the crux of obtaining satisfactory therapeutic effects and preventing recurrence.

Presented in this paper were 3 cases of a special kind of polymorphic ventricular tachycardia (VT). The clinical manifestation was recurrent syncope without organic heart disease. The electrocardiogram (ECG) was characterized by normal QT intervals with short-coupled variant of torsade de pointes. The efficacy of treatment with classI,I,I antiarrhythmic drugs was not apparent but verapamil had an excellent therapeutic effect for it. This kind of VT had a high incidence of sudden death, so it was very important for physicians to identify and treat it promptly with long-term verapamil. The mechanism of short-coupled variant of torsade de pointes was unclear. It probably had some relationship with triggered activity or imbalance of autonomic nervous system.

To explore the effect of NF-κB on bcl-x gene transcription in extended drug resistance leukemia cell line HL-60/E6, drug-resistant subline HL-60/E6 was derived by intermittently exposing HL-60 cells to 6 ng/ml epirubicin. Indirect immunofluorescence was used to demonstrate the location of NF-κB-RelA in HL-60/E6 cells. FCM analysis and RT-PCR were used to detect the efficiency of liposome-mediated ODN transfection and the change of bcl-X_L. mRNA levels after 5 μmol/L phosphorothioate (PS)-derivatized antisense (AS) oligodeoxynucleotide (ODN) directed to RelA was transferred into HL-60/E6 cells. The results showed that RelA remained persistently active and located at the nuclei of HL-60/E6 cells, but in the cytoplasm of HL-60 cells, the efficiency of liposomemediated ODN transfection was significantly higher than that of null ODN (P<0. 01 in 4 h, 6 h, 12 h, 24 h). Exposure of HL-60/E6 cells to 5 μmol/L AS-PS-ODN directed to RelA led to a maximal 40 % decline of bcl-x_L mRNA levels within 8 h. The inhibition rate of bcl-X_L. mRNA was (15±1. 79) %, (28±2. 34) %, (40±3.47) %, (20±1.54) % in 4 h,6h,8h, 15 h, respectively, but it was less than 15 % in control group. It was concluded that NF-κB was involved in regulating bcl-x transcription. It was suggested that NF-κB was an important factor for drug resistance in leukemia cells.

To validate the accuracy and consistency of respiratory inductive plethysmography (RIP) in measuring tidal volume after an overnight sleep, tidal volumes of 18 patients with suspected sleepdisordered breathing and 8 normal volunteers were measured simultaneously with RIP (V_TRIP) and with an ultrasonic airflow meter (V_TUFM) before and after an unstrained overnight sleep on supine and lateral decubitus. The bias of the V_TRIP was expressed as (V_TRIP-V_TUFM)/ V_TUFM 100 %, limits of agreement between V_TRIP and V_TUFM was measured by averaged bias ±2s. Results showed that in normal subjects, the bias of RIP before and after overnight sleep was precise and consistent in both supine (0. 7 % and -1. 6 %) and lateral decubitus (3. 7 % and -0. 56 %). In these patients, the bias of RIP before and after sleep in supine also remained small (1. 9% and 1.7%), but it became larger in lateral decubitus (24. 5 % and 20. 4 %) and 11. 5 % exceeded the limits of agreement observed in the evening. The patients’ body mass indices (BMI) were higher than those of normal subjects (median 34. 2 vs. 27. 8 kg/m²). Pooled data showed that the bias of V_TRIP in the morning on lateral decubitus but not on supine was correlated to BMI (Spearman R = 0. 32, n=52,P=0.02). Thus, we were led to conclude that the accuracy of V_TRIP overnight was precise and consistent in normal subjects, but the deviation of V_TRIP measured on lateral decubitus in patients especially in those with excessive obesity was greater, thus, the method should not be used for quantitative determination.

To investigate the clinical value of three-dimensional ultrasonography (3DUS) in obstetrics, various 3DUS rendering methods including surface mode, transparent mode and multiplanar mode were employed to scan 30 fetuses in second and third trimester by using the transabdominal volume transducer. The results showed that surface mode could vividly demonstrate the surface morphologic features of the fetuses, as well as the stereo-shape and the spatial relationship among the surface structures. The face, limbs, umbilical cord and outer genitalia of the fetus could be well displayed by surface mode. Transparent mode could reveal the bony structures under the surface, such as ribs, vertebrae, crania, etc. The result was not affected by the sophisticated curvature of these bony structures and the success rate was up to 100%. When rendered by multiplanar mode, the region of interest (ROD could be viewed from different directions. It should be concluded that 3DUS could serve as a supplement to two-dimensional ultrasonography (2DUS). 3DUS might play an important role in prenatal diagnosis and enhance the diagnostic confidence level of the physicians.

Seventy-four cases of infertility were examined to study the hemodynamics of the bilateral ovarian arteries at 21st day during the corpus luteum phase by color Doppler energy(CDE) and color Doppler flow imaging (CDFI). All the patients were verified by laparoscopy, fallopian tube patency examination and ovarian function test. Twenty-two healthy women served as controls. The results showed that the difference of resistance index(RI)and pulsatility index (PI) of bilateral ovarian arteries between the infertility and the normal controls had statistical significance (P<0. 01), and the PI showed negative correlation with the thickness of endometrium (left side: r=0. 724,P<0. 01; right side: r=0. 756,P<0. 01). The results also showed that CDE was more sensitive than CDFI in displaying the ovarian arteries. It could be concluded that the elevated resistance of ovarian artery during the corpus luteum phase was one of the important factors that resulted in infertility.

ATP was added to the cultured sensory neurons obtained from the dorsal root ganglia of the neonatal rats and PBS was added to serve as control. MTT assays were conducted to evaluate the survival and activity of the cultured neurons. And the silicone regenerative chamber was used after the sciatic nerve incision of the mature SD rat. 1 mmol/L ATP was injected into the left chamber and 0. 09 % natrium chloride was injected into the right chamber as controls. The changes of nitric oxide synthase (NOS) activity in the corresponding dorsal root ganglia were measured histochemically and image analysis was also performed 4 days after the sciatic nerve injury. The results showed that extracellular ATP could enhance the survival of the neurons and the number of NOS positive neurons were significantly different between the ATP and control groups (P<0. 05). It was suggested that extracellular ATP had neurotrophic effect on neurons survival and could inhibit the NOS activity of the sensory neurons after the peripheral nerve incision, hence exerting the protective effect on the neurons, which was valuable for nerve regeneration after nerve injury.

Exogenous gene suture was used to achieve peripheral nerve anastomoses to probe into the feasibility that the sites of anastomoses of nerves directly transfer gene and thus enable gene to be expressed at the sites of anastomoses under the condition that perfect nerve anastomoses are ensured. PCMVß plasmid containing cytomegalovirus promoter (CMV promoter) and Escherichia coli (E. coli) ß-Galactosidase (ß-Gal) structural gene (lacZ gene) was conducted. A soaked medical 8-Onylon suture was used to perform epineurial repair of rabbit sciatic nerve. In the control group a suture soaked in sucrose PBS was used, while in the experimental group a suture soaked in PCMVß plasmid solution was applied. The sites of anastomoses of nerves by stages were taken out, and ß-Gal histochemical staining was performed and ß-Gal enzyme activity was assayed with 5-bromo-4-chloro-3-indolyl-ß-D-galactoside. Results showed that the sites of anastomoses of nerves were taken out 2 days, 7 days, 14 days and 30 days respectively after the operation. The ß-Gal histochemical stains at the sites of anastomoses showed no indigo positive cells at different stages in the control group, whereas displayed indigo positive cells in the experimental group. In the control group, no ß-Gal enzyme activity was detected at different stages after operation, but in the experimental group, ß-Gal enzyme activity could be detected from the 3rd day to the 30th day after operation. It was concluded that by using exogenous gene suture, exogenous gene could be transferred to the sites of peripheral nerve and expressed the exogenous gene expression products with bioactivity, which provided the feasibility of using gene therapy to accelerate the recovery of nerve function.

The expression of multidrug resistant proteins in bladder cancer and clinical implication was studied. Expression of multidrug-associated protein (MRP), P-glycoprotein (P-gp), P53 and Bcl-2 proteins were detected by using immunohistochemical method in 40 specimens of bladder transitional cell carcinoma. The results showed that the positive rate of MRP, P-gp, P53 and Bcl-2 was 52. 5 %, 57. 5 %, 47. 5 % and 62. 5 % respectively. The positive rate of MRP, P-gp, P53 and Bcl-2 in the grade I, I andI of tumors was 46. 3 %, 38. 5 %, 38. 5 %, 23. 1 %; 52. 9 %, 39. 8 %, 47. 1 %, 76. 4 %; 60. 0 %, 80. 0 %, 60. 0 %, 90. 0 % respectively. The positive rate of MRP, P-gp, P53 and Bcl-2 in 24 primary tumor specimens was 37. 5 %, 41. 7 %, 33. 3 %, 45. 8 % and that in 16 cases in recurrent specimens receiving chemotherapy 75. 0 %, 81. 3 %, 68. 8 %, 87. 5 % respectively. It was suggested the positive rate of MRP, P-gp, P53 and Bcl-2 was increased with the advance of tumor grade. The positive rate of four proteins in all recurrent cases was significantly increased (P<0. 05). The expression of MRP, P-gp, P53 and Bcl-2 proteins might be the important factors for chemotherapy failure.

The reactivity of human preformed natural antibodies (PNAbs) with various porcine pancreatic cells and its isotypes was investigated. Eighteen serum samples from patients with insulin-dependent diabetes mellitus (IDDM) and 20 serum samples from healthy human subjects were collected. The frozen sections of the pig pancreas were incubated with these sera, and subsequently incubated with FITC-conjugated goat antihuman IgG and IgM monoclonal antibodies. The reactivity of human PNAbs with various porcine pancreatic cells was determined by indirect immunofluorescence staining technique. The results showed that 55. 6 % of IDDM patients and 55. 0 % of healthy human individuals contained PNAbs against porcine endocrine cells. However, the percentage of strongly reacting sera in the patient group was significantly increased as compared with that in the control group. All used sera from IDDM patients and 95 % of sera from healthy controls could react to one or more of the various pancreatic cell types, including: endocrine cells, exocrine cells, vascular endothelial cells, ductal epithelial cells and macrophages. The isotypes of PNAbs contained both IgG and IgM. In view of strongly positive reactivity of PNAbs with various porcine pancreatic cells, pretransplantly cross-matching test and graft pretreatment may be necessary for survival of islet transplants.

Anin vivo model of glutamate excitotoxicity in which glutamate is applied to the cortex of rats through a microdialysis probe has been used to investigate the neuroprotective processes initiated by 17ß-estradiol. Rats were pre-treated with 17ß-estradiol i. v. before local application of glutamate. The experimental results showed that pre-treatment with 17ß-estradiol significantly reduced the size of the glutamate-induced lesion. In the microdialysates, the peak of lactate observed immediately after glutamate application was significantly higher and longer lasting after 17ß-estradiol pre-treatment. The level of extracellular glucose was markedly decreased concomitantly to the increase in lactate, but no difference could be observed with and without 17ß-estradiol pre-treatment. These suggest a new neuroprotective mechanism of 17ß-estradiol by activating glutamate-induced lactate production. This effect on lactate production and lesion reduction is estrogen receptor dependent and is abolished totally by estrogen antagonist tamoxifen. It was also demonstrated here that high lactate subserves estrogen neuroprotection during glutamate toxicity.

To evaluate the relationship between erythrocyte injury and intracellular calcium ion overload, and the protective effect of propofol on erythrocytes during cardiopulmonary bypass (CPB), 40 children with congenital heart diseases who underwent surgical repair under CPB were studied. The patients were randomly divided into two groups: control group (group C) and propofol group (group P). Anesthesia was maintained in the patients in group P with 6 mg · kg^-1 · h^-1 propofol, and those in the group C inhaled 1% – 2% isoflurane. The blood samples were taken before CPB, at the 30th min of CPB, at the end of CPB, and 2 h and 24 h after CPB to measure the content of erythrocyte intracellular calcium ion (E-Ca²⁺), Ca²⁺-Mg²⁺-ATPase and Na⁺-K⁺-ATPase activities, index filtration of erythrocytes (IF), mean corpuscular volume (MCV) and the concentration of plasma free hemoglobin (F-HB). Results showed that in the control group, E-Ca²⁺, IF, MCV and F-Hb were gradually increased and Ca²⁺-Mg²⁺-ATPase and Na⁺-K⁺-ATPase activities were decreased. The increase of E-Ca²⁺ was linearly paralleled to IF, MCV and F-Hb. In propofol group, all the above-mentioned parameters were significantly improved (P<0. 05). This study suggests that erythrocyte injury is related to elevation of intracellular calcium during CPB and propofol has a protective effect on erythrocyte injury.

Regulation of the adhesion molecules expression by cytokine in vascular endothelial cells was investigated. Human umbilical vein endothelial cells (HUVEC) were stimulated with cytokines, TNF-α (1–250 U/ml) or IL-1ß (0. 1–50 U/ml) for 24 h. HUVEC were also cultured with cytokines, TNF-α (100 U/ml) or IL-1ß (10 U/ml), for 4–72 h, cell surface expression of adhesion molecules (ICAM-1 and VCAM-1) were detected and quantitated by immunocytochemical methods and computerized imaging analysis technique. Adhesion molecules expression were up-regulated by TNF-α, IL-1ß in a concentration- and time-dependent manner. Some significant differences were observed between the effects of cytokines on the ICAM-1 and on VCAM-1 expression. Cytokines might directly induce the expression of ICAM-1 and VCAM-1 in vascular endothelial cells. Our observations indicate differential functions of the two adhesion molecules during the evolution of inflammatory responses in stroke.

The efficacy and safety of leflunomide (LEF) in the treatment of rheumatoid arthritis (RA) were evaluated and the comparison with methotrexate’s (MTX’s) was performed in a 12-week, single-blind, randomized, parallel trial for treating 81 patients with RA. There were 56 cases in LEF group and 25 cases in MTX group. The dose of LEF was 20 mg per day and MTX 15 mg per week. All patients took oxaproxin simultaneously at the 4th to 6th week after the trail. The results showed that the general effective rate and notable effective rate were 94. 64 % and 73. 21 % in LEF group, 72 % and 44 % in MTX group, respectively, with the differences being statistically significant between the two groups (P<0. 05). LEF and oxaprozin could obviously improve the symptoms, signs and joint functions. The incidence of side reactions was lower in LEF group (17. 86 %) than in MTX group (40. 00 %,P<0. 05). LEF had a good therapeutic effect for RA, especially for refractory RA and had slight side reactions, and could be regarded as a superior immunosuppressive agent used in the treatment of RA and other connective tissue diseases.

172 cases of pregnant women scheduled for delivery by cesarean section were randomly assigned to 59 cases in modification group with modified Misgav Ladach technique, 57 cases in Misgav Ladach group with Misgav Ladach technique and 56 cases in Pfannenstiel group with Pfannenstiel technique from May to Dec. 1999. The modified points included: transversely incising the fascia 2 to 3 cm, then dividing it bluntly; without opening and dissociating the visceral peritoneum; two layers suturing of low transverse uterine incision; closing the skin by continuous suturing. Results showed the average delivery time in the modification group was (3. 6±2. 6) min and (5. 7±2. 9) min in the Misgav Ladach group (P<0. 05). Median operating time was (28. 3 ±5. 4) min in modification group compared with (27. 5±6. 5) min in the Misgav Ladach group (P>0. 05). Average blood loss was (128±35) ml in modification group compared with (212±147) ml in the Pfannenstiel group (P <0. 05). It was concluded that the modified Misgav Ladach technique not only preserved all advantages of Misgav Ladach method, but also had additional advantages, such as faster in delivering the fetus, less damage, easier mastering for obstetricians.

To investigate the role of nitric oxide (NO) in hyperoxic lung injury, the 3-day-old preterm rats were randomly assigned to four groups: group I (hyperoxia group), groupI (hyperoxi-a+N^w-nitro-l-arginine methyl ester (L-NAME) group), groupI (air group), and group IV (air+ L-NAME) group. Group I and I were exposed to ≥90 % O₂ for 3 or 7 days. GroupI and IV received subcutaneous L-NAMEy on daily basis (20 mg/kg). After 3 day or 7 day exposure, the lung wet weight/dry weight ratio (W/D), total protein and malondialdehyde (MDA) in bronchoalveolar lavage fluid (BALF) and lung pathology were examined in all groups. NO content, expression of endothelial NOS (eNOS) and inducible NOS (iNOS) in lungs were measured in group I andI. Our results showed that after 3 day exposure, group I appeared acute lung injury characterized by the increase of MDA content (P<0. 01) and the presence of hyperaemia, red cell extravasation and inflammatory infiltration; after 7 day exposure, except MDA, total protein and W/D were also increased in comparison with groupI (P<0. 01, 0. 05), pathological changes were more severe than those after 3 day exposure. After 3 and 7 day exposure, total protein in groupI was significantly increased as compared with group IP<0. 01 for both). The pulmonary acute inflammatory changes were more obvious in group I than in group I. Occasionally, mild hemorrhage was detected in the lungs of group IV. BALF protein content in group IV was higher than that in groupI after 7 day exposure (P<0. 01). After 3 and 7 day exposure, NO content in BALF were all significantly elevated in group I as compared with groupI (P<0. 01 for all). In the lungs of group I, strong immunostaining for iNOS was observed in airway and alveolar epithelia, inflammatory cells, which were stronger than those in groupI. Expression of iNOS in rats after 7 day hyperoxic exposure was stronger than that after 3 day exposure. Shortly after 7 day exposure, stronger immunostaining for eNOS in airway epithelia in group I than that in groupI was seen. Our study suggested that treatment with L-NAME worsened acute hyperoxic lung injury in preterm rats and also had a deleterious effect on the rats exposed to air, indicating that endogenous nitric oxide may play a protective role in rats under both physiological and hyperoxic status. Hyperoxia can significantly upregulate the expression of iNOS and eNOS in inflammatory cells, epithelia in the lungs of preterm rats, promote NO generation, which suggests that endogenous NO may mediate the hyperoxic pulmonary damage. Over-stimulation of iNOS may contribute to the pathogenesis of hyperoxic lung injury. NO may have dual roles in pulmonary oxygen toxicity.

In order to explore whether the conventional use of 5-fluorouracil (5-Fu) had any toxic effects on trabecular meshwork cells, bovine trabecular meshwork cells were cultured in vitro and exposed to 5-Fu at different concentrations. The cellular morphology, ultrastructure, mortality and phagocytosis were studied under light microscopy, transmission electron microscopy and methods of Wright’s stain. It was found that the toxic effects of 5-Fu on the cells were in a dose-dependent mode. 1 X 10^-1 mg/ml of 5-Fu caused a large part of cells rounded up, while 1 X 10^-3 mg/ml of the drug only a rough appearance of the cell surface. Exposure to 1 X 10^-2 mg/ml of 5-Fu made mitochrone swollen and rough endoplasmic reticulum enlarged, with the cell mortality being 50. 5%. The latex microspheres engulfed in cytoplasm in cells receiving 1 X 10^-1 and 1 X 10^-2 mg/ml of 5-Fu were significantly decreased as compared with those in the control group (P<0. 01). It was concluded that the safe concentration of 5-Fu on bovine trabecular meshwork cells was 1 X 10^-3 mg/ml and the conventional dosage of 5-Fu in clinical practice would not cause injury to trabecular meshwork cells.

To investigate the possible role of interleukin (IL)-10 and IL-12 in the pathogenesis of psoriatic lesions and to supply theoretical basis for the gene therapy for psoriasis, the expression of IL-10 and IL-12 P35, P40 mRNA in 12 cases of psoriatic lesions and 6 normal skin tissues was detected by using RT-PCR technique. The results showed that the expression of IL-10 mRNA in the psoriatic lesions was significantly lower than that in the normal skin tissues (P<0. 001). The expression of IL-12 P35 was positive both in the psoriatic lesions and in the normal skin tissues. IL-12 P40 mRNA was expressed positively only in the psoriatic lesions but negatively in the normal skin tissues. It was suggested that IL-12 might take an important role in the occurrence and progression of psoriasis, but IL-10 might have certain role in the regression of psoriasis.

The ligand-binding domain of VLDL receptor contains eight imperfectly similar repeats. To discuss the contribution of each repeat to ligand binding, the RT-PCR technique was used to clone the VLDLR-cDNA from the heart muscle of Chinese people. Two recombinants were further constructed, which contained the full-length cDNA of VLDLR and the mutant lacking repeats 1–5. CHO cell line was transfected with two recombinants. The expression of VLDLR gene could be detected by RT-PCR from the CHO cells transfected with pCD-VR. The results of binding experiments showed that the ability of the CHO cells transfected with the full-length cDNA of VLDL-R binding Dil-labeled β-VLDL was higher than that of the CHO cells transfected with the mutant. Our findings indicated that human VLDL-R gene could be expressed effectively on CHO cells, and the receptor was almost inactivated when repeatsl-5 were deleted.

In order to find out the potential modulators which influence the secretion of TNFα, the relationship between the amount of secreted TNFα(sTNFα) and the level of TNFα converting enzyme (TACE) gene expression was studied before and after the stimulation by lipopolysaccharides (LPS) to HL-60 cells and adhered cells isolated from human spleen using cytological and molecular biology techniques and methods (RT-PCR, Dot-blot hybridization, etc.). The experimental results showed that: (1) LPS could induce the increase of expression of TNFα mRNA and TACE mRNA, reaching the peak value at 6 h and 10 h respectively after addition of LPS into cell culture medium; (2) The anti-sense oligodeoxyribonucleotide (A-ODN) complementary to TACE mRNA sequence really inhibited the secretion of TNFα as a result of blocked translation of TACE gene; (3) Furthermore, it was also observed that RDQ, a kind of injection derived from Chinese traditional herb, had strongly inhibitory effects on the expression of TACE mRNA and secretion of sTNFα stimulated by LPS. The above results suggested that the TACE indeed involved in delivering and processing of pro-TNFα during the period of LPS stimulation and the study about the regulator/inhibitors of TACE gene expression would be very important to develop new types of therapy agents against toxic and side effects of sTNFα during the peroid of infection/inflammation to human body.