Comparative luminescence of rat liver Cu-thionein and its chemically synthesized alpha-domain

A peptide corresponding to the alpha-domain of rat liver metallothionein-2 was chemically synthesized employing the solid phase peptide synthesis technique. Its luminescence properties that depend on the coordinated Cu(I) have been studied using luminescence spectrometric titration in the presence of Cu(I). Unlike the intact metallothionein which has been converted into the Cu species, the emission and excitation spectra of the Cu-alpha-fragment showed a red shift by 20 nm and 65 nm, respectively, suggesting a more compact and stable luminophore in the alpha-domain. Saturation of Cu(I) coordination was reached in the presence of 6.5 mol eq Cu(I) when the alpha-fragment was used and 12 mol eq Cu(I) were specifically bound by the intact metallothionein. The emission bands were homogeneous and no decline of the cluster structure was observed when excessive Cu(I) was added after saturation. A rearrangement of the Cu-cluster in metallothionein during its formation seems to be plausible.

Reactivity of active center analogs of Cu2Zn2 superoxide dismutase on activated polymorphonuclear leukocytes

In unseparated human blood the Cu2Zn2 superoxide dismutase mimetic reactivity of several differently coordinated low Mr copper chelates on TPA-activated polymorphonuclear leukocytes was evaluated and compared to their apo-chelates, CuSO4, and the native enzyme. Similar to intact superoxide dismutase, 350-400 nM Cu flexibly complexed in a di-Schiff base mode in CuPu(Py)2 and CuPu(Im)2, respectively, was sufficient to inhibit the oxidative burst-dependent superoxide production of human blood phagocytes by 50%. Acetate- or biuret-type copper chelates behaved like CuSO4. The catalytic superoxide dismuting reactivity of the di-Schiff base active center analogs of SOD was confirmed using isolated porcine PMNs. Even in the presence of 600 microM albumin as a model for competitive copper chelation in biological fluids CuPu(Py)2 and CuPu(Im)2 remained active. The stability during the Cu(I)/Cu(II) redox cycling was demonstrated in the presence of activated PMNs and albumin, taking advantage of the electron paramagnetic properties of CuPu(Py)2 and CuPu(Im)2.

[Study of factors associated with preterm delivery]

A case-control study of preterm delivery was undertaken at the district of Qiaokou in Wuhan during October, 1987 to May, 1988. The study population consisted of 130 mothers of singleton preterm infants and 260 mothers of singleton term infants. The result of logistic regression analysis showed that significant factors of preterm delivery included low maternal stature, the young age of menarche, a previous induced abortion, a history of infertility problems, vaginal bleeding during the pregnancy, low weight gain during the pregnancy, premature rupture of membranes, hyperemesis gravidarum, and lack of antenatal care. The result also showed that psychosocial stress in pregnancy might be related to preterm delivery.

Efficacy of inactivated vaccine containing cyto-hemagglutinin against epidemic hemorrhagic fever in rabbits

Using the Z-10 strain of epidemic hemorrhagic fever virus (EHFV) as seed, and the primary cell of Meriones unguiculatus kidney tissue as incubation cell, a propiolactone inactivated epidemic hemorrhagic fever (EHF) vaccine was prepared, according to a similar procedure required for the production of biological products such as the Japanese B encephalitis vaccine. Besides the EHFV antigen detected by ELISA or reversed passive hemagglutination test (RPHA) as were used for the formalin inactivated vaccine, higher titres (1:128-1:1024) of EHFV hemagglutinin antigen was also detected in this EHFV vaccine. Immunization with twice intramuscular injection of this vaccine produced high titred (1:20-1:160) neutralizing antibody and low titred (1:10-1:20) hemagglutination antibody, in addition to the immunofluorescence (IF) and reversed passive hemagglutination inhibition (RPHI) antibodies. These results indicated an apparent difference in the immunogenicity between the beta-propiolactone and formalin inactivated EHF vaccines. With the approval of the Ministry of Health, human test is now underway in this laboratory.

Anti-idiotypic antibodies: preparation and identification; application to the detection of antigens of Plasmodium falciparum

Anti-idiotypic antibodies (anti 94D1Id and anti 94C3Id) were prepared by immunizing rabbits with designated monoclonal antibodies (MoAb) 94D1MoAb (94D1Id) and 94C3MoAb (94C3Id) specific for Plasmodium falciparum. The specificity of both was directed against idiotypes of the relevant MoAb. The interaction between 94D1Id and anti94D1Id or 94C3Id and anti94C3Id was almost completely inhibited when sufficient concentration of P. falciparum antigen was added, suggesting that the idiotypes recognized by anti94D1Id or anti94C3Id were located in the antigen binding site of the MoAbs or the construction of the V region of anti-idiotypic antibodies may be similar to that of P. falciparum antigenic determinants combining with MoAb. Each 4i assay (inhibition of idiotype-anti-idiotype interaction) had a different specificity and sensitivity in detecting P. falciparum asexual antigens. The 94C3Id-anti94C3Id system detected a minimal level of 0.001% parasitaemia and did not cross-react with other species, suggesting that 94C3Id-anti94C3Id system is species specific and may become a valuable tool for immunodiagnosis.

Inhibitory, opsonic and cytotoxic activities of monoclonal antibodies against asexual erythrocytic stages of Plasmodium falciparum

A range of monoclonal antibodies specific for Plasmodium falciparum were tested in vitro for their abilities to inhibit the multiplication of a partially synchronized culture of P. falciparum, to augment the phagocytosis of the parasites by macrophages, and to enhance the killing of parasites by peritoneal cells depleted of adherent cells. Seven of 17 monoclonal antibodies, ranging from culture supernatant fluid and ascitic fluid to purified IgG, showed dose- and time-dependent inhibition of parasite growth in vitro. At a concentration of 0.6 mg/ml, the inhibitory capacity of these monoclonal IgGs was above 94% over a 3-day culture period, much higher than that of the relevant polyclonal IgG. Four of 6 monoclonal antibodies tested augmented the phagocytosis of the parasites by macrophages, which occurred as a result of opsonization of the parasites. Four of 7 monoclonal antibodies examined showed cytotoxic activity on malaria parasites. Peritoneal cells depleted of adherent cells were capable of killing the parasites in the presence of monoclonal antibodies. These results indicate that there may be 'monofunction', 'bifunction', and 'multifunction' types of monoclonal antibodies against P. falciparum. The putative protective antigen of malaria parasites purified by 'multifunctional monoclonal antibody' affinity chromatography may have potential interest as a vaccine against the parasite or as an immunodiagnostic reagent for human malaria.

The production of reactive oxygen species in mice infected or immunized with Plasmodium berghei

The capacity of peritoneal exudate cells (PEC) obtained from mice infected or immunized with Plasmodium berghei to produce reactive oxygen species (ROS) and the biological basis of this response was investigated, using luminol-dependent zymosan-triggered chemiluminescence (CL). CL response of PEC from infected mice increased at the early stage but was significantly depressed at the later course of the infection. A similar biphasic activity of peroxidase was also observed in PEC from infected mice. On the other hand, PEC from immunized mice exhibited concomitant increases of the ability to produce CL, the activity of peroxidase and the expression of Fc and C3 receptors on cell surface. Compared with the controls, PEC from immunized mice showed an elevated background CL, responded more rapidly to the stimulation and generated considerably higher CL when triggered with opsonized zymosan. The data suggest that phagocytes in immunized mice are active in the production of ROS while those in infected mice are less active, and the inhibition of the ability of phagocytes to produce ROS may be one of the mechanisms for the parasites to escape from host immune system.

[Application of trichosanthin in 179 difficult cases of artificial abortion]

This article introduces the application of compound crystal trichosanthin to 179 difficult cases of artificial abortion including cases with extreme anteversion and anteflexion of uterus with a fine and long cervix, cases with uterine deformations, cases within 1 year after cesarotomy, and cases of recently induced abortion. Past experiences have indicated that there have been considerable difficulties in inducing abortion in such cases as the above, and that accidents have been liable to occur. The authors have recently employed compound crystal trichosanthin, composed of crystal trichosanthin, testosterone propionate and reserpine, and succeeded in bringing about drug expansion of uterus and abortion, and safe abortion at that. The success roles were as follows: 97.96% for the group with extreme anteversion and anteflexion of uterus with a fine and long cervix, 100% for the one with uterine deformations, 95.08% for the one with past cesarotomy and 96.72% for the one with recently induced abortion.

Pharmacology of radioiodinated hexadecenoic acid--a myocardial imaging agent

123I- and 131I-labeled hexadecenoic acid (IHDA, radiochemical purity over 92%, dissolved in 6% bovine serum albumin solution) was investigated in vivo. ICR mice were administered IHDA via the tail vein. Maximum myocardial uptake (27.3 +/- 5.1%) was reached about 0.5 min after the injection. The ratio of uptake in the heart to that in the lungs was 2.3, to that in liver 1.5 and to that in other organs 2.4 to 6.4. The dog myocardium was visualized distinctly within 3-5 min with a gamma camera after i.v. 131I-IHDA, and not interfered with by activities in the lungs, liver and other organs. The low blood levels at 20 min had little effect on the quality of the heart images.