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X W Li

Publications and source records attributed to X W Li.

10 recordsLinked to original sources
PubMed1992

[Studies on the strain differences of Schistosoma japonicum in the mainland of China. VII. Genetic variation and differentiation of five isolates].

Electrophoretic techniques have been used to survey five different field-collected isolates (i.e., Anhui, Hubei, Guangxi, Sichuan and Yunnan) of S. japonicum from the mainland of China for genetic variation at 7 isozymes markers representing 9 loci. Polymorphic loci were observed for LDH-1, LDH-2, MDH and PGM, respectively, the proportion of polymorphic loci being 44.4%. Average heterozygosity varied between 0.223 and 0.425, with a mean of 0.332. Nei's genetic distance (D) among the populations of 5 isolates gave values between 0.001 and 0.039 with an average of 0.023, indicating that these isolates are very closely related.

Alleles↗
PubMed1991

Anticancer gelatin microspheres with multiple functions.

Biodegradable, hydrophilic gelatin microspheres (GM) with an average diameter of 70 microns were prepared by cross-linking gelatin with glutaraldehyde for hepatic intra-arterial infusion. An anticancer agent, mitomycin C (MMC), together with a radioisotope, 131I, were bound to the GM for chemotherapy and local internal radiotherapy. The 131I-labelled MMC-GM (131I-MMC-GM) could accumulate in the specific site and embolize the hepatic arteries after the hepatic intra-arterial infusion, while it caused various effects to the liver cells. The 131I-MMC-GM remained within the hepatic arteries for at least one month. In vitro release of drugs from the GM was also quantified using a dynamic dialysis method.

Animals↗
PubMed1991

The immunosuppressive properties of enisoprost and a 5-lipoxygenase inhibitor (SC-45662).

Metabolic derivatives of arachidonic acid such as prostaglandins and leukotrienes may alter immune responses. Enisoprost (ENO), a synthetic prostaglandin E analog, inhibited the response of human peripheral blood mononuclear cells to phytohemagglutinin in a concentration-dependent fashion: .1, 1.0, and 10 micrograms/ml yielding 4.0, 21.7, and 74.3% inhibition, respectively. ENO also potently inhibited both IL-2 production (measured by ELISA) and IL-2 responsiveness (measured by CTLL-2 response to IL-2) in a concentration-dependent manner, yet did not inhibit acquisition of IL-2 receptors. ENO similarly diminished efferent immune function in a concentration-dependent fashion, as measured by inhibition of cytotoxic T cell and natural killer effector function. A 5-lipoxygenase inhibitor (5-LO), SC-45662, also inhibited mononuclear cell response to PHA in a concentration-dependent manner: 0.1, 1.0, and 10 micrograms/ml yielding 5.0, 9.7, and 79.7% inhibition, respectively. Although 5-LO potently inhibited IL-2 production, it had no effect on IL-2 responsiveness or IL-2 receptor acquisition. Like ENO, 5-LO impaired CTL and NK effector function yet was not as potent in inhibiting CTL effector function. In summary, ENO and 5-LO inhibit afferent and efferent immune function. The inhibitory effects of these drugs are not related to cytotoxicity as cell viability is maintained for 72 hr in the presence of these drugs, and the inhibitory effect is reversible when the drugs are removed. The 5-LO does not inhibit mononuclear cell responses simply by shunting the formation of arachidonic acid precursors to form inhibitory prostaglandins, since it does not impair IL-2 responsiveness in a manner similar to ENO. These two compounds may prove to have clinical utility in organ transplantation if safely achieved serum concentrations of these drugs yield in vivo immunosuppression parallel to our in vitro results.

Acetates↗
PubMed1991

[Experimental study on the treatment of hypertension with combined traditional Chinese and Western medicine].

In order to study the connection of diastolic activity of smooth muscles of blood vessels with development of hypertension, plasma cAMP, cGMP, TXB2, 6-K-PGF1 alpha, ANP, SP were determined with radioimmunoassay, of 173 hypertension patients with Liver Yang exuberance (LYE) 91 cases, and Yin deficiency and Yang exuberance (YDYE) 82 cases. In addition, 228 health subjects served as control. The results showed that the levels of cAMP, cGMP and TXB2 in both LYE and YDYE groups were higher than those in the control group, but the levels of ANP, SP and cAMP/cGMP ratio in LYE and YDYE groups were lower than those in the control. As to the level of 6-K-PGF1 alpha, no significant variance was found between these groups. After TCM-WM treatment, the levels of cAMP, cGMP and TXB2 in LYE and YDYE groups got down, as compared with those in the control, adversely the levels of ANP, SP and 6-K-PGF1 alpha in LYE and YDYE groups turned up significantly. However the cAMP/cGMP ratio had no remarkable change between these groups. The linear regression analyses between the diastolic pressure and ANP or SP both proved negative correlation (r = -0.36, P less than 0.05; r = -0.35, P less than 0.05). The findings indicated that the TCM-WM treatment was the most effective among the therapies employed in the study, and that this therapy affected the diastolic activity of smooth muscles by modulating the above factors existing in the nervous and endocrine systems of the patients with hypertension.

6-Ketoprostaglandin F1 alpha↗
PubMed1991

[Studies on strain differences of Schistosoma japonicum in the mainland of China. VI. Analysis with multilocus enzyme electrophoresis].

Five different field-collected isolates (i.e., Anhui, Hubei, Guangxi, Sichuan and Yunnan) of Schistosoma japonicum from the mainland of China were compared by means of multilocus enzyme electrophoresis in polyacrylamide gels of individual male worm extracts. The enzyme systems used in the study included GDH, G6PD, LDH, MDH, PGI, PGM and SOD. Of 9 loci examined in the 7 isozyme systems, 4 were found to be polymorphic. These were LDH-1, LDH-2, MDH and PGM, the remainder of GDH, G6PD-1, G6PD-2, PGI and SOD being monomorphic. Our results indicated that the genetic polymorphism occurring in the natural population of different isolates of S. japonicum in the mainland of China. The allele frequencies at polymorphic loci coding for enzyme as well as the genetic identity and genetic distance in different isolates of S. japonicum will be reported elsewhere.

Alleles↗
PubMed1990

Radix Tripterygium wilfordii--a Chinese herbal medicine with potent immunosuppressive properties.

Radix Tripterygium wilfordii Hook-F (TW) is a Chinese herbal medicine that has been reported to be effective in the treatment of various autoimmune disorders in experimental animals and man. Little is known about the immunosuppressive mechanism of action of this medicine. We demonstrate herein that TW is capable of inhibiting several afferent immune functions including the in vitro response of human peripheral blood mononuclear cells to both mitogen and alloantigen, and the generation of cytotoxic T cells. This inhibition is likely mediated through a reduction in both IL-2 production and IL-2 responsiveness. TW evidenced little capability of impairing IL-2 receptor expression, or efferent immune mechanisms such as cell-mediated cytotoxicity or natural killer cell-mediated cytotoxicity. The immunosuppressive effects of TW were reversible except at the highest concentration tested, 2.4 micrograms/ml, and there was no evidence of TW-mediated cell-well damage as evidenced by trypan-blue exclusion. TW, or some of its constituents, may be important new agents to be studied for immunosuppression in organ transplantation.

Adult↗