Biomedical subjects

G L Wu

Publications and source records attributed to G L Wu.

At least 37 records · Page 2Linked to original sources

PubMed1993

[A study on the monoclonal anti-idiotypic antibody NP30 for the diagnosis of schistosomiasis japonica].

In this study the ability of the monoclonal anti-idiotypic antibody NP30 was tested as a substitute of diagnostic antigen in detecting antibody of Schistosoma japonicum from human sera by use of ELISA. The results showed that the seropositive rate was 98% with NP30 in the group of acute infection, which was comparable to 94% with gut associated antigens (GAA) and 98% with the soluble egg antigens (SEA); 87% with NP30 in the group of chronic infection which was comparable to 86% with GAA but lower than that of 98% with SEA. The false positive rate was about 3% for all three diagnostic antigens. The results also showed that the geometric mean titer (GMT) of antibody to NP30 was higher than that to GAA but lower than that to SEA in the acute infection group and the GMT of antibody to NP30 was lower than both those to GAA and to SEA in the chronic infection group, suggesting that the antibody to NP30 appeared earlier and decayed more quickly during the process of infection. The authors suggested that NP30 could be used for the diagnosis of schistosomiasis japonica.

Animals↗

PubMed1993

Immunodiagnosis of Schistosoma japonicum infection in China.

Diagnosis is an essential prerequisite for the control programs of schistosomiasis. Chinese scientists have been making efforts for decades towards the development of immunological approach in an attempt to offer alternatives of or supplements to parasitological diagnosis. The authors outline briefly the main advances in the research of immunodiagnosis for schistosomiasis japonica in China in two catalogues: antibody detection and antigen detection. A number of immunodiagnostic assays based on antibody detection, which have been used widely in the control programs in China, are appraised in terms of sensitivity and specificity, and the achievements in the development of immunodiagnostic assays based on antigen detection are introduced. Readers will find some information concerning the efforts so far made by Chinese scientists in the improvement of immunodiagnosis by use of molecular approach, including search for biochemically and/or immunochemically isolated and/or purified antigens, recombinant antigens and anti-idiotypic reagents of diagnostic interest to construct defined antigen-antibody systems for diagnosis, and development of monoclonal antibody-based assays for antibody or antigen detections.

Animals↗

PubMed1992

[Production and characterization of a murine protective monoclonal antibody against Schistosoma japonicum schistosomula].

Eight murine monoclonal antibodies against surface determinants of Schistosoma japonicum (Chinese mainland strain) schistosomula were generated, of which only one monoclonal IgM antibody (N15D9) gave protection at level ranging from 14 to 39% in experiments of passive transfer or inhibition of infectivity while the others did not exhibit significant levels of passive protection. Further characterization of N15D9 antigen specificity showed that 96 and 14 kDa antigen molecules in cercaria, and 132 and 10 kDa in schistosomula could be recognized by N15D9 in Western blot assay. Furthermore, the 96 and 132 kDa molecules could also be recognized by pooled infected human sera while 14 kDa and 10 kDa only by sera from mice vaccinated with 3-hour schistosomula. The molecules recognizable by N15D9 were surface epitopes repeatedly expressed on cercaria, in vitro 3-hour mechanically transformed schistosomula and 5 day lung-stage schistosomula, as demonstrated by indirect immunofluorescence surface binding assay.

Animals↗

PubMed1991

Liposomes as MR contrast agents: pros and cons.

Liposomes are generally thought of as being useful for entrapping drugs within their internal aqueous space. When used with MR contrast agents, this has the drawback that water flux across the membrane bilayer is limiting to contrast enhancement. This can be partially overcome by making the liposomes very small, such that surface area is relatively great compared to internal volume, thereby facilitating water exchange. Alternatively the membranes can be designed to be permeable to water but this may render the vesicles unstable in serum. Another approach is to incorporate the contrast agents into the lipid bilayer. By designing novel complexes of manganese with the ligands incorporated onto dual acyl chains, we have achieved R1 and R2 values of over 20/mmol sec-1 or more than five times higher than Gd-DTPA. Hepatic metastasis detection is significantly improved in rats at doses of only 10 mumol/kg manganese. Membrane-bound manganese complexes function as highly effective liver imaging agents and merit further study for development as agents to undergo human clinical trials.

Animals↗

PubMed1991

[The establishment and characterization of the anti-idiotypic monoclonal antibody-NP30 of Schistosoma japonicum].

A hybridoma cell line secreting an IgM monoclonal antibody designated NP30 was obtained from a fusion of SP2/o and spleen cells of a BALB/c mouse chronically infected with schistosoma japonicum for one and a half year and identified by screening with immunized rabbit sera against gut-associated antigen (GAA) and soluble egg antigen (SEA) of S. japonicum, indicating that the NP30 was an anti-anti-antigen or anti-antibody. NP30 was further determined to be an anti-idiotypic antibody (anti-id) which was serologically and functionally identical to GAA, so that it could be portrayed as the internal image of GAA, which might have the potential to be used as an antigenic reagent in immunodiagnostic assays of schistosomiasis japonica.

Animals↗

PubMed1991

[Clinico-epidemiological investigation of schistosome-induced hepatosplenomegaly: a community-based study in Jishan, Xinjian County, Jiangxi].

Since the primary objective of mass chemotherapy in schistosomiasis control is reduction of schistosome-induced morbidity, it would be reasonable to assess the impact of a control program on the morbidity in a given population by investigating hepato-splenomegaly associated with schistosomiasis in a schistosomiasis endemic area. In this paper, the authors described the relationship between the prevalence, intensity and morbidity of Schistosoma japonicum infection in terms of stool egg count and ultrasonographically detectable hepatosplenomegaly in a community-based study. It was found that the epidemiological pattern of the infection in this study community was quite different from our usual understanding, that is, the prevalence remained relatively high (39.4%) when the intensity became lower. This unusual pattern might be resulted from intermittent and sporadic chemotherapy associated with frequent exposure of people to the infection in an area of high transmission. It was surprised to note that despite the praziquantel treatment carried out over the past years, the prevalence of hepatosplenomegaly induced by schistosomiasis in this community was still very high, suggesting that intermittent and sporadic chemotherapy might render little impact on schistosomiasis-induced morbidity. The investigation also showed that ultrasonography was a sensitive tool for assessing morbidity associated with schistosome infection.

Adolescent↗

PubMed1991

[Preliminary study of naturally occurring anti-idiotypic antibodies in schistosomiasis japonica].

In this study, naturally occurring anti-idiotypic antibodies in sera from patients with schistosomiasis japonica were demonstrated by using McAb (5B5H)-ELISA. McAb 5B5H against Schistosoma japonicum soluble egg antigen (SEA) was purified by precipitation with 50%, 40% and 33% saturated (NH4)2SO4 and coupled to CNBr-activated Sepharose 4B (Pharmacia). 5B5H column was loaded with sera from two patients with schistosomiasis japonica and then the bound material was eluated with 3M KCNS. The resulting eluate was further characterized with McAb-ELISA and complement fixation test in order to minimize the possible interference of circulating antigen-antibody complex. The results showed that the eluate contained mainly anti-Id antibodies. In the competitive 5B5H-ELISA tests, SEA markedly inhibited the interaction of 5B5H (Id) and anti-Id anti-bodies, suggesting that the relevant idiotype is within or adjacent closely to antigen binding site of anti-SEA molecule. The anti-Id antibodies were detected using 5B5H-ELISA in patients with schistosomiasis japonica from A and B areas, positive rate of 35.1% (13/37) and 60% (18/30) was obtained respectively. No cross or false reactions were found with sera from patients with fasciolopsiasis buski (0/15), clonorchiasis sinensis (0/15) and normal group of students (0/54) with the exception of one out of 20 patients with paragonimiasis westermani.

Animals↗

PubMed1990

[1:R matched case-control studies with fixed and varying numbers of controls].

This paper introduces the use of the Mantel-Haenszel estimator in 1:R matched case-control studies with fixed and varying numbers of controls matched to each case. The new methods of variance estimator of the Mantel-Haenszel estimator of a common odds ratio were provided. These methods were also summarized into the method of calculating table in order to present a simple, convenient and easily understanding method for the readers.

Case-Control Studies↗

PubMed1989

[Studies on DNA methylation in transformed mouse liver cells].

Activity of DNA methylase and DNA methylation level were measured from normal mouse liver, mouse liver charged with H22a ascitic hepatoma and H22a ascitic hepatoma cell by measuring incorporation of H3-methyl. S-Adenosyl-3H-methyl-methionine (3H-SAM) was used as methyl donor. DNA methylation level of different cells were measured by HP-LC. DNA methylase activity and DNA methylation level of H22a ascitic hepatoma, mouse liver charged with H22a ascitic hepatoma are lower than normal mouse liver. Treatments of antitumor drugs lead to a rising of DNA methylase activity of tumor cell, however, the DNA methylation level of tumor cell has not rised after such treatments.

Animals↗

PubMed1988