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S Q Li

Publications and source records attributed to S Q Li.

At least 37 records · Page 2Linked to original sources
PubMed1998

Effect of histidine on myocardial mitochondria and platelet aggregation during thrombotic cerebral ischemia in rats.

AIM: To study the effect of histidine on cerebral thrombosis and possible mechanism. METHODS: Cerebral-cardiac stroke was produced by photochemically induced thrombotic cerebral ischemia in rats. RESULTS: Platelet aggregation in whole blood increased markedly, peak heights at 4 and 24 h were (5.1 +/- 0.5) omega and (4.3 +/- 0.5) omega, respectively. Heart mitochondria volume (V), volume density (Vv), surface density (Nm), and surface density of outer membrane (Sv1) increased (8.2 +/- 5.5, 0.59 +/- 0.16, 0.11 +/- 0.03, and 0.22 +/- 0.05, respectively, P < 0.01), but numerical density (Nv), specific surface of inner membrane (delta 2) and of the cristae (delta 3) decreased (0.07 +/- 0.02, 2.8 +/- 0.8, and 2.4 +/- 0.7, respectively, P < 0.01) after cerebral thrombosis. The myocardial histopathologic characteristics were different from those of ischemic necrosis and myocardial damage caused by ischemic reperfusion. In rat treated with histidine after photochemical reaction, platelet aggregation decreased markedly [(2.93 +/- 1.08) omega, P < 0.01], reversible change often went with parameters related to the inner mitochondrial membrane but not the outer mitochondrial membrane. CONCLUSION: Histidine depressed platelet aggregation and reduced myocardial mitochondrial damage resulted from cerebral ischemia.

Animals↗
PubMed1998

[A chromosomal integration system for development of polyvalent vaccine strains].

We have developed a potential bivalent vaccine stain through the chromosomal integration system in which the gene that codes for the B subunit of cholera toxin was integrated into the chromosome of an attenuated strain of Salmonella typhimurium. This system involves two steps: construction of a hisOG deletion mutation into the chromosome of S. typhimurium strain SL3261: and replacement of the hisOG deletion by the complete hisOG region and the segment of heterologous DNA which codes for the B subunit of cholera toxin. The recombinant strain SL3261 (named TT201) was obtained. Southern hybrid confirmed that the CTB gene was integrated into the chromosome of TT201. Western blot analysis demonstrated that the CTB gene was expressed stably in TT201. When administered orally to mice, the recombinant strain elicited a serum antibody response to CTB. The strain TT201 is a potentially bivalent vaccine candidate.

Animals↗
PubMed1997

Stable transfection of nonosteogenic cell lines with tissue nonspecific alkaline phosphatase enhances mineral deposition both in the presence and absence of beta-glycerophosphate: possible role for alkaline phosphatase in pathological mineralization.

It is documented that alkaline phosphatase (AP) plays an important role in bone mineralization. Considering that TN-AP is expressed in periodontal ligament fibroblasts, renal epithelial cells, and vascular endothelial cells, and that TN-AP is both a calcium-/phosphate-binding protein and a phosphohydrolytic enzyme, we hypothesize that membrane-bound AP also plays an important role in the initiation of physiological and pathological mineralizations in tissues other than bone and cartilage. To test this hypothesis, nonosteoblast cell lines, including a fibroblast line, a renal epithelial line, and a capillary endothelial line, were stably transfected to express high levels of rat bone AP on their cell surfaces. These rat bone AP-expressing cells were then cultured on filter membranes in the presence or absence of beta-glycerol phosphate. von Kossa staining for calcium phosphate and transmission electron microscopy with electron diffraction analysis for minerals were employed to investigate the effect of membrane AP on extracellular calcium phosphate mineralization. Our results indicated that AP expression on these nonosteoblast-like cell surfaces have induced extracellular hydroxyapatite (HAP) mineralization. Our findings support the concept that membrane-bound AP contributes to extracellular apatitic mineralization by mechanisms that do not necessarily involve its hydrolase activity. They also suggest that AP might be important for the initiation of pathological mineralization in nonosteogenic tissues.

Alkaline Phosphatase↗
PubMed1996

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

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

Activin Receptors↗
PubMed1996

Defective post-thymic tolerance mechanisms during the chronic progressive stage of multiple sclerosis.

We have recently isolated a panel of T-cell clones from chronic progressive multiple sclerosis (MS) patients that are capable of functioning as antigen-presenting cells and of expressing the costimulatory molecules B7-1 and B7-2. In this report we show that these T-cell clones are resistant to inhibitory regulation, including the induction of anergy and sensitivity to tumor growth factor-beta (TGF-beta)-induced growth inhibition. The resistance to anergy induction was associated with expression of B7 costimulatory molecules. These data suggest that lack of responsiveness to peripheral inhibitory signals may account for the entry of autoimmune diseases into a chronic progressive phase.

Adult↗
PubMed1995

Expression and localization of inhibin alpha-subunit in rat retinal photoreceptor cells.

To determine whether rat retinal photoreceptor cells produce inhibin, a molecule closely related to activin, a multifunctional growth factor in the transforming growth factor beta superfamily (TGF beta), we have conducted immunohistochemistry using specific antibodies for inhibin which were raised against a synthetic N-terminal fragment of the alpha-subunit of inhibin. The mature inhibin molecule was identified at both the inner and outer segments of photoreceptor cells. To determine if messenger RNA for the alpha-subunit of inhibin is expressed in the retinal cells, both in situ hybridization with a specific probe and the reverse transcription-polymerase chain reaction (RT-PCR) technique with primers specific for the alpha-subunit of inhibin were used. Messenger RNA expression of the alpha-subunit of inhibin was detected by RT-PCR and localized in the photoreceptor cells as determined by in situ hybridization. In addition, the identity of the cDNA product of RT-PCR was verified with Southern analysis and DNA sequencing. The localization of mature inhibin protein and its corresponding message to photoreceptor cells suggest that inhibin may have a paracrine function in the retina, perhaps in the photoreceptor cells themselves.

Animals↗
PubMed1995

Proteins in fluid from the proximal vas deferens of normal fertile and vasectomized men.

Fluids were collected from the proximal vas deferens of 18 normal fertile men and 32 vasectomized men during vasectomy or vasovasostomy, respectively, and the protein concentration and pattern of proteins were then analysed by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE). In normal fertile men and vasectomized men there were no significant differences in total protein concentrations between fluids from the left and right vas deferens. The total protein concentration of proximal vas fluid from vasectomized men (82.8 +/- 7.5 mg/ml; mean +/- SEM) was significantly higher than in normal fertile men (36.8 +/- 4.5 mg/ml). In vasectomized men there was no significant correlation between the total protein concentration in vas fluid and the duration of vasectomy. The patterns of protein bands in proximal vas fluid differed from those in seminal plasma. There was no relationship between the pattern of protein bands in vas fluid and the duration of vasectomy. Five major groups of proteins from proximal vas fluid were identified and no new major proteins were found in proximal vas fluid were identified and no new major proteins were found in proximal vas fluid after vasectomy. The percentage of 80K and 67K protein bands in vasectomized men was higher than that in normal fertile men. It is suggested that, after vasectomy, the physiological environment of the proximal vas deferens may be changed. One of these changes may be the higher total protein concentration (especially the 80K and 67K proteins) in vas fluid.

Adult↗
PubMed1995

Histidine ameliorated brain edema and cardiac dysfunction during local thrombotic cerebral ischemia in rats.

AIM: To observe the effects of histidine (i.v. 5 mg.kg-1) on brain edema and cardiac disturbance after cerebral thrombosis. METHODS: Regional cerebral thrombosis was induced by photochemical method in rats. RESULTS: It was showed that the brain water content increased markedly (85.6 +/- 3.8%, P < 0.01); the left ventricular systolic pressure (LVSP, 17.9 +/- 1.5 kPa) and the maximal left ventricular contractility decreased (+dp/dtmax 645 +/- 110 kPa and -dp/dtmax 473 +/- 106 kPa, P < 0.05). In rats treated with histidine after photochemical reaction, the brain water content decreased (81.5 +/- 2.0%) while LVSP (21.2 +/- 1.1 kPa) and left ventricular +dp/dtmax and -dp/dtmax increased markedly (777 +/- 144 kPa and 604 +/- 157 kPa, respectively). CONCLUSION: Histidine has protective effects on the brain and cardiac function during cerebral thrombosis.

Animals↗
PubMed1995

[Clinical observation on the treatment of ischemic heart disease with Astragalus membranaceus].

92 patients suffering from ischemic heart disease was successfully treated with Astragalus membranaceus (AM). The effect of the treatment was compared with that of Nifedipine and Tab. Salviae miltiorrhizae. The clinical practice showed that the group treated with AM yielded better results. After having administered the drug, the patients were markedly relieved from angina pectoris (heart stroke). Meanwhile the improvement of clinical objective index such as electrocardiogram (EKG) and impedance cardiogram can also be observed. The effective rate of EKG improvement was 82.6%. The treatment of ischemic heart disease with AM was significantly more effective in comparing with control group (P < 0.05).

Adult↗
PubMed1994

Analysis of spermatozoa from the proximal vas deferens of vasectomized men.

This study assessed the condition of spermatozoa from the proximal vas deferens of men after vasectomy. The fluids of both proximal vas deferens were collected from 67 vasectomized men by cannulating the vas deferens at the time of vasectomy reversal. Selected sperm parameters were analysed after incubation of the spermatozoa for 30 min at 37 degrees C. Sperm concentration in the proximal vas from vasectomized men (16,312 +/- 21,496 million per ml, geometric mean: 7948 +/- 398 million per ml) was significantly higher than that of fertile men and was maintained at a constant level independent of the duration of vas obstruction. The means of sperm motility (36.2 +/- 26.2%), spermatozoa with normal morphology (50.7 +/- 21.7%), sperm viability (53.0 +/- 25.3%) and hypo-osmotic swelling test (HOS-test, 53.9 +/- 21.7%) were statistically lower than the respective values for normal fertile men. There was no significant correlation between the duration of vas obstruction and the above semen parameters. In 46.4% of vas fluids all spermatozoa were immotile and this condition was more common after 3 years of vasectomy. Immotile spermatozoa in the proximal vas fluids at the time of vasectomy reversal may be an important factor for predicting semen quality and fertilizing ability after vasovasostomy. There were no significant differences in the results of sperm-cervical mucus penetration test (CMPT) between spermatozoa from vasectomized and fertile men. Antisperm antibodies on the surface of spermatozoa from the vas of vasectomized men were determined by the immunobead test (IBT; 78.6% for IgG, 32.1% for IgA) and sperm cervical mucus contact test (SCMC, 36.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Prophylactic effects of zhuling and BCG on postoperative recurrence of bladder cancer].

The prophylactic effects of Chinese herbal medicine Zhuling (Grifola umbellata pilat) and BCG on bladder cancer after TURBT and partial cystectomy were evaluated. 146 patients with bladder cancer were divided into 3 groups, Zhuling, BCG, and control group. Follow-up for 48-124 months (average 70.8 months) showed that the tumor recurrence rate was 33.3%, 34.3% and 65.1%, respectively. Compared to the control group, the recurrence rate of Zhuling group and BCG group was significantly decreased (P < 0.01). The effect of Zhuling was similar to that intravesical BCG. Zhuling was cheaper and convenient in usage, and no side effects.

Administration, Intravesical↗
PubMed1994

[Double J stent for pelvis-ureter junction stricture].

Twenty-one patients (27 ureters) with pelvis-ureter junction stricture were treated by persistent dilatation with indwelling double J stent in the ureter. The double J stents were inserted by means of retrograde cystoscopic approach. The duration of stents left in the ureters was 3 approximately 12 months. Follow-up for 5 approximately 36 months after removed the double J stents showed the extinction of the symptoms, remission of the hydropyonephrosis and improvement of the renal function. The excretion urography and retrograde pyelography showed improvement of stricture in 25 ureters. We suggest that persistent dilatation with double J stent be used as first choice for treatment of pelvis-ureter junction stricture.

Adolescent↗
PubMed1994

[Squamous cell carcinoma of urinary epithelia: report of 15 cases].

From May 1983 to 1992, 15 patients with urinary epithelial squamous cell carcinoma in renal pelvis (7) and in bladder (8) were treated. Eleven of them were complicated by urinary tract stone. Of the 15 patients, 8 were misdiagnosed as having simple urinary stone and 1 renal tuberculosis. It is suggested that active treatment for urinary stones be used to prevent the occurrence of squamous cell carcinoma and that possibility of concomitant epithelial tumor in patients with long-term and large urinary stones be considered.

Aged↗