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S X Liu

Publications and source records attributed to S X Liu.

At least 91 records · Page 5Linked to original sources
PubMed1992

Effects of m-nisoldipine and nisoldipine on electric activity of human atrial tissue.

Using intracellular microelectrode technique and microcomputer analyzing system, the effects of m-nisoldipine (m-Nis) and nisoldipine (Nis) on spontaneous electric activity of human atrial tissue were studied. APA and Vmax were remarkably decreased by m-Nis (0.25 and 1.25 mumol.L-1) and Nis (0.25 mumol.L-1). RPF was also greatly decreased as a result of inhibition in VDD. The inhibitory effects of m-Nis on transmembrane potentials were less than those of Nis at equal concentration (0.25 mumol.L-1). Neither MDP nor APD90 was affected by m-Nis and Nis.

Action Potentials↗
PubMed1991

[Experimental study of schistosome immune RNA on transfer of cellular and humoral immunity to normal mice].

The present paper reported the extraction of immune RNA (iRNA) from spleen cells of Schistosoma japonicum infected rabbits and the activity of this schistosome iRNA (SiRNA) on transfer of cellular immunity and humoral immunity using macrophage migratory inhibition test (MMIT) and Dot-ELISA. The results indicated that specific cellular immunity could be transferred to normal mice by SiRNA either via in vivo or in vitro sensitization. Intraperitoneal inoculation of SiRNA to normal mice may result in production of specific antibodies.

Animals↗
PubMed1991

[Anti-antibody responses of rabbit to mouse monoclonal antibody against schistosome "target antigen"].

The supernatant of protective McAb (isotype IgG2a) secreted by 1E2 hybridoma line was purified by protein A-sepharose CL-4B column and rabbits were immunized with purified 1E2 McAb. Dot-ELISA, immunodiffusion assay, Western blotting and ELISA were used to observe the presence of anti-McAb and anti-anti-McAb. The main results are: 1. anti-McAb antibody could be detected as early as 20 days post immunization in the immune sera and would be decreased gradually without boosting; otherwise, it would be increased quickly and the titers of anti-McAb were increased within 5 days post-boosting and could be maintained at a plateau for 30-50 days, and then decreased gradually to the normal; 2. there were different anti-anti-McAbs in the immune sera. Anti-anti-McAb, like anti-anti-idiotype antibody, can recognize different schistosome antigens and 90, 68 or 45 kDa antigenic determinants. The level of anti-anti-McAbs varied from titers 1:100 to 1:1600 at different time post-immunization with 1E2. The results provide evidence to understand the appearance of anti-McAb antibody and the way to develop anti-idiotype and anti-anti-idiotype McAb for research purpose.

Animals↗
PubMed1990

[Construction of a cDNA library of Schistosoma japonicum].

The template mRNA was extracted from Schistosoma japonicum. The first strand of cDNA was synthesized by AMV-reverse transcriptase. The second strand cDNA was first digested by RNase H to remove mRNA and was then synthesized by AMV-reverse transcriptase, T4-DNA polymerase. Sizing of cDNA was applied on a NACS column to remove small fragments of less than 1 kb. Homopolymeric tailing of vector (pUC18) was done with dGTP and DNA terminal transferase and tailing of the cDNA with dCTP was carried out under the same conditions. After annealing, the plasmids with cDNA were transformed into E. coli MC1061. The efficiency of cloning was about 10(4)/micrograms mRNA with 30% of the transformants having the inserts of cDNA (Figs. 1-2).

Animals↗
PubMed1990

[Factors influencing prognosis of tongue cancer: a retrospective study of 260 cases].

This paper is a retrospective study of prognostic factors involved the tongue cancers. The 3 and 5 year survival rates of the tongue cancer were 63.77% 61.2%, respectively. I. The prognosis in females was poorer than that of males II. The prognosis of oral tongue cancer was better than oropharyngeal tongue cancer. III. The larger the cancer, the poorer the prognosis. IV. Node involvement was an important factor influencing survival rate. V. Immediate repair of defect did not influence survival rate. VI. The main cause of death was recurrence of the primary site, which generally occurred within 3 years postoperatively. The authors suggest that I. The depth of the tumours infiltration should be an index for the evaluation of prognosis. II. The neck dissection, either functional or radical, should be carried out as a routine. III. The management of mandible will be determined according to the tumor infiltration. IV. immediate reconstruction is recommended.

Adolescent↗
PubMed1990

[Screening of Schistosoma japonicum adult worm genomic DNA library by specific antibody].

S. japonicum adult worm genomic DNA libraries were screened by enzymeimmunoassay. The antigens produced by recombinant lambda gt 11 plaques were transferred to nitrocellulose filters. Clones encoding given antigens were detected with infected rabbit sera (IRS) which were preabsorbed with lysate of induced lambda gt 11 in Y1090 cells. Eight putative positives were picked up from 97 plates in the primary screening and were rescreened a second time, and, 2 of them consistently gave good positive signals in subsequent screenings. One of the phage clones was purified to homogeneity and mixed with Y1089 cells. The expressed products still showed positive when rescreened by ELISA, indicating that the clone encoding S. japonicum antigen could be recognized by IRS. The immunoscreening method described here was able to efficiently isolate single clones encoding S. japonicum antigens. The method has the advantages of screening libraries efficiently, reliably and specifically, and it might open the way to screen genes encoding S. japonicum antigens inducing protective immunity (Fig. 1).

Animals↗
PubMed1990

[Study on McAbs against protein "target antigen" in Schistosoma japonicum].

In the studies presented here, we demonstrated the feasibility of producing large number of hybridoma cell lines secreting McAbs against S. japonicum including 16 cell lines secreting IgG McAbs (7 for IgG1, 5 for IgG2a, 1 for IgG2b, 3 for IgG3) and 13 McAbs for IgM, on the basis of successfully extracting 24-26kD and 90kD "target antigen" proteins known as important antigens for inducing schistosome protective immunity. All the above cell lines were characterized for localization of the McAbs, mediating in vitro ADCC against schistosomula, epitope recognized by the McAbs on different kinds of schistosome antigens. Studies have shown the evidences that the McAbs can be used to identify the "target antigen" on the surface of schistosome, to isolate and purify "target antigen" of S. japonicum by chromatography column bearing McAbs, as well as to immunize animals as antigens for accumulation of data in the development of vaccine against S. japonicum via anti-idiotype antibodies.

Animals↗
PubMed1989

[Further study on the immunity induced by mutagenic NTG attenuated cercariae of Schistosoma japonicum].

In order to understand the immunity induced by NTG attenuated cercariae of S. japonicum, investigations were carried out on the survival rate of mice, worm reduction rate, liver and spleen granulation etc. at different intervals between immunization and challenge (4, 6, 8, 10 and 12 wk) in mice exposed percutaneously to NTG attenuated cercariae (30 micrograms/ml NTG for 15 min). Scanning electron microscopy on tegumental surface of schistosomes from immunized mice was also performed. Results showed that better protection was achieved at a challenge time of 8 wk after initial immunizing infection as demonstrated by the higher worm reduction rate and the longer survival rate with a lower degree of liver granulation. It is suggested that acquired immunity did develop against a challenge in mice exposed to NTG-attenuated cercariae, but there were different levels of immunity at different times post-immunization. Thus week 8 appeared to be the optimal time for acquired immunity developed against a challenge infection. The possibility of induction of different levels of immunity was discussed.

Animals↗
PubMed1989

Life table method for analyzing relationship between smoking and hypertension.

The life table method is introduced for describing the relationship of smoking amount to prevalence rate of hypertension. The smoking level at different sex groups are collected and grouped according to their cumulative smoking amount. Using the total number of peasants, and the number of hypertensives in each group, one is able to calculate the probability of occurrence of hypertension for each dose group as well as for each cumulative dose group, which indicated that there was a dose-effect curve in estimating the relationship between the cumulative smoking and the probability of hypertension, and females presented a significantly higher probability of hypertension than males in same smoking level.

Adult↗
PubMed1989

[Humoral and cellular immunity in mice immunized with mutagenic NTG-attenuated cercariae of Schistosoma japonicum].

Observation was made on humoral and cellular immunity in mice immunized with NTG-attenuated cercariae. Results showed that the specific antibody in serum of immunized mice increased gradually. The titer by ELISA and IFA were more than 1:1,280 respectively at week 7 post-immunization with NTG-attenuated cercariae (15 min. pc or 60 min. ip). SDS-PAGE electrophoresis showed that there was an extra-band of IgG with MW, between 50,000 and 40,000 in the serum of immunized mice and there was no obvious difference in IgM bands. It suggested that there were differences in not only the increase of antibody titre, but also the composition of antibody post-immunization. The results also indicated that there were differences in levels of lymphocyte proliferative response to schistosome antigens at different weeks post-immunization. The proliferative response to SEA was greater in immunized mice than in infected mice, especially in lymph node lymphocytes. It suggested that NTG-attenuated cercariae did stimulate mice to produce immunity. The dynamic characteristics of humoral and cellular immunity may play roles in the induction of protective immunity against S. japonicum.

Animals↗