Immunogenicity of a recombinant fusion protein of tandem repeat epitopes of foot-and-mouth disease virus type Asia 1 for guinea pigs

In this study, the sequences of capsid protein VPI regions of YNAs1.1 and YNAs1.2 isolates of foot-and-mouth disease virus (FMDV) were analyzed and a peptide containing amino acids (aa) 133-158 of VP1 and aa 20-34 of VP4 of FMDV type Asia I was assumed to contain B and T cell epitopes, because it is hypervariable and includes a cell attachment site RGD located in the G-H loop. The DNA fragments encoding aa 133-158 of VP1 and aa 20-34 of VP4 of FMDV type Asia 1 were chemically synthesized and ligated into a tandem repeat of aa 133-158-20 approximately 34-133-158. In order to enhance its immunogenicity, the tandem repeat was inserted downstream of the beta-galactosidase gene in the expression vector pWR590. This insertion yielded a recombinant expression vector pAS1 encoding the fusion protein. The latter reacted with sera from FMDV type Asia 1-infected animals in vitro and elicited high levels of neutralizing antibodies in guinea pigs. The T cell proliferation in immunized animals increased following stimulation with the fusion protein. It is reported for the first time that a recombinant fusion protein vaccine was produced using B and T cell epitopes of FMDV type Asia 1 and that this fusion protein was immunogenic. The fusion protein reported here can serve as a candidate of fusion epitopes for design of a vaccine against FMDV type Asia 1.

A recombinant fusion protein and DNA vaccines against foot-and-mouth disease virus type Asia 1 infection in guinea pigs

On the basis of amino acid (aa) sequence of the tandem repeat 133-158-20-34-133-158 which consisted of aa 133-158 of VP1 and aa 20-34 of VP4 of Foot-and-mouth disease virus (FMDV) type Asia 1 a recombinant prokaryotic expression vector pAS1-P encoding a fusion protein and eukaryotic expression vectors pAS1-E and pAS1-EdeltaCpG-ODN representing DNA vaccines were constructed. Guinea pigs immunized with these vaccines showed both neutralizing antibody and T cell proliferation responses. FMDV challenge tests for the first time showed that the recombinant fusion protein and pAS1-E and pAS1-EdeltaCpG-ODN vaccines protected 86%, 60% and 43% of guinea pigs from FMDV type Asia1 challenge, respectively. The results also indicated that the immune response of animals treated with the vector pAS1-E containing an oligodeoxynucleotide (ODN), which consisted of immunostimulatory cytosine-phosphate-guanosine (CpG) motifs, was augmented by CpG ODN.

A serologically identified tumor antigen encoded by a homeobox gene promotes growth of ovarian epithelial cells

Ovarian carcinomas are thought to arise from cells of the ovarian surface epithelium by mechanisms that are poorly understood. Molecules associated with neoplasia are potentially immunogenic, but few ovarian tumor antigens have been identified. Because ovarian carcinomas can elicit humoral responses in patients, we searched for novel tumor antigens by immunoscreening a cDNA expression library with ovarian cancer patient serum. Seven clones corresponding to the homeobox gene HOXB7 were isolated. ELISAs using purified recombinant HOXB7 protein revealed significant serologic reactivity to HOXB7 in 13 of 39 ovarian cancer patients and in only one of 29 healthy women (P < 0.0001). Ovarian carcinomas were found to express HOXB7 at markedly higher levels than normal ovarian surface epithelium, suggesting that immunogenicity of HOXB7 in patients could be associated with its elevated expression in ovarian carcinomas. Overexpression of HOXB7 in immortalized normal ovarian surface epithelial cells dramatically enhanced cellular proliferation. Furthermore, HOXB7 overexpression increased intracellular accumulation and secretion of basic fibroblast growth factor, a potent angiogenic and mitogenic factor. These results reveal HOXB7 as a tumor antigen whose up-regulated expression could play a significant role in promoting growth and development of ovarian carcinomas.

[The genetic analysis of amplitude of progesterone secretion in serial blood collection from tail in min sows]

28 adult Min sows (3-7 parities), represented 9 sire families were selected to conduct the continual blood collection from the tail for two hours at the interval of ten minutes between 9:00-11:00 in the morning on the sixth day after the last mating. The content of progesterone was assayed by radio-immunological assay. The amplitudes of the secretion of progesterone were generated by the procedure of HORM fft. exe complied by the author. It is difficult to get a reasonable conclusion from the content analysis, because the content varied widely between different points of blood collection in single sow. After Fourier conversion, the heritability of amplitude for the fifth partial wave was high (h2 = 0.932); middle for the basal, 2nd and 3rd partial waves; lower for others. This supported the idea that prolific sows had more active secretion of progesterone in luteal cells. The coexist of low and high heritability components in amplitude of progesterone secretion showed that the activities of progesterone secretion were influenced by both the genetics and environments. The genetic correlation of basal, 1st, 5th partial waves were negative, the others were positive, with the litter size and litter size alive. It showed that the reproductive performance of Min pigs were not expressed perfectly, as the balance of secretion of progesterone did not reach the best. The genetic correlation of all partial waves with duration of estrus was negative which supported that the progesterone suppresses the estrus. The genetic correlation of 3rd, 5th partial waves were stronger than others, but selection for 5th partial wave would make high responses than the 3rd wave, because the genetic correlation of 3rd partial wave with litter size and litter size alive was positive, therefore, the more appropriats method of selection for progesterone was adopted, the better results would be achieved in the improvement of indirect selection response for litter size.

Tracer and electrical coupling of rat suprachiasmatic nucleus neurons

Whole-cell recording from single neurons of the suprachiasmatic nucleus with an electrode containing the tracer neurobiotin resulted in the staining of multiple neurons in 30% of the cases. Typically, one neuron was darkly stained with dendritic processes and an axon clearly visible while other neurons were lightly stained. The darkly-stained cells were identified as the recorded neuron and tracer-coupled to one to five lightly stained neurons. The resting membrane potential, input membrane conductance, membrane capacitance, the decay time constant and the maximum H-current amplitude of the recorded neurons with tracer-coupled cells were not significantly different from those of neurons not showing tracer coupling. Stimulation of the preoptic area activated an antidromic action potential or an all-or-none small slow inward current in some neurons when the synaptic transmission was blocked by a calcium-free/Mn2+ solution. The small slow inward current did not "collide" with an orthodromically activated action spike suggesting that the current represents the signal from an electrotonically-coupled neuron. In addition, the frequency of biphasic field currents from a neighbouring cell firing were increased by depolarization and decreased by hyperpolarization of the recorded cell. These data demonstrate a chemical and electrical low-resistance coupling of suprachiasmatic nucleus neurons, which could be important in synthesizing the suprachiasmatic nucleus circadian rhythm.

[Clinical study of zhinu-I,-II in treating 61 patients with idiopathic thrombocytopenic purpura]

The article studied 61 patients with idiopathic thrombocytopenic purpura, they were classified and treated with Chinese herbal medicine Zhinu (ZN) -I, -II, in comparison with 30 cases of patients treated with prednisone. The results showed that the effect of prednisone was more effective than ZN- I, -II in four weeks (P < 0.05). On the contrary, follow up for 12 months, the effect of ZN-I, -II were more effective than prednisone (P < 0.05) and the possibility of recurrence was lower (P < 0.01). In addition, blood platelet counts of the patients treated with ZN-I, -II increased slower, but lasting for longer term. The conclusion indicated that the ZN-I, -II were safe and effective. There was no obvious side effects.

Microscopic observations on livers of rabbits and dogs infected with Schistosoma japonicum cercariae and early treatment with artemether or praziquantel

To study the histopathological change of the liver of the hosts treated with artemether (Art) or praziquantel (Pra) in early stage after infection with Schistosoma japonicum cercariae.

METHODS

Dogs infected once with schistosome cercariae were treated ig with Art 10 mg.kg-1 or Art capsule (ArtC) 15 mg.kg-1 on d 7, or praziquantel (Pra) 30-40 mg.kg-1 on d 21 after infection, followed by the repeated dosing once every 1 or 2 wk for 2-4 times. In rabbits, infected with 48-52 schistosome cercariae once every other day for 5 times, were treated ig with Art 10 mg.kg-1 or Pra 30 mg.kg-1 was started on d 7 or on d 21 after the first infection, followed by the repeated dosing every 1 or 2 wk for 2-3 times.

RESULTS

After above mentioned dogs or rabbits were treated ig with Art, ArtC or Pra, the female worm reduction rates were 92.1%-100%. Histopathological examination showed that the reduction rates of total granuloma in the liver sections of the dogs and rabbits were 70.9%-97.3% and 76.5%-97.4%, respectively. Meantime, the structure of the hepatic lobules was normal with normal arrangement of the liver bundle.

CONCLUSIONS

Early treatment with Art or Pra exhibited a promising effect of protection of the liver of the dogs and rabbits infected with schistosome cercariae. Early treatment of infection with schistosome cercariae kills the Female worms before oviposition. Thus, the host will be protected from the damage caused by schistosome eggs. Promising results were obtained when mice and rabbits received an early treatment with artemether (Art) or praziquantel (Pra). This work was to study the liver infected with cercariae and treated by intragastric gavage (ig) with Art, Art capsule (ArtC) or Pra in early stage after infection.

Differential metabolism of exogenous platelet-activating factor by glandular epithelial and stromal cells of rabbit endometrium

Significant changes in platelet-activating factor (PAF; 1-O-alkyl-2-acetyl-sn-glycero-3-phosphorylcholine) concentration have been observed in rabbit endometrium during the preimplantation period, but, under in vitro conditions, constitutive PAF biosynthesis by isolated endometrial tissues was not easily demonstrable. Relative changes in enzymes involved in the synthesis and metabolism of PAF in the tissues may account for this disparity. In addition, during this period of preimplantation, marked changes in PAF receptor concentration have been noted. The present study examines the factors that may modulate the metabolism of exogenous [3H]PAF in the endometrium of rabbits on day 6 of pregnancy. Since preferential [3H]PAF binding in situ by the glandular epithelial, but not by the stromal, cells was demonstrated, their cell-specific metabolism of exogenous [3H]PAF was also examined. After entry into the endometrial cell, [3H]PAF was rapidly metabolized by the sequential action of cytosolic Ca(2+)-independent acetylhydrolase to [3H]lyso-PAF and this was in turn acylated by membrane-associated transacylase to [3H]alkylacyl-glycerylphosphorylcholine. PAF resynthesis was not observed and, in stromal cells, there was a significant build-up of [3H]lyso-PAF, suggesting that lyso-PAF:acetyl-CoA acetyl-transferase may be a limiting factor. In the glandular epithelial cells, however, there was a significant accumulation of a neutral lipid without a significant build-up of [3H]lyso-PAF or [3H]PAF. The neutral lipid co-migrated with the product of phospholipase C-catalysed metabolism of PAF and authentic 1-O-hexadecyl-2-acetyl-glycerol. In addition, the elution times of phospholipase C digestion of C18 PAF and the neutral lipid produced by cellular metabolism of [3H]PAF, determined by gas chromatography/flame ionization detection, were similar. It seems that it is the synthesis of the neutral lipid from reacetylated [3H]lyso-PAF that prevented [3H]PAF accumulation under in vitro conditions. This is the first documentation of the synthesis of this lipid in the mammalian uterus. The lipid may serve as the precursor for de novo PAF synthesis in the glandular epithelial cells during endometrial proliferation.

Experimental studies on early treatment of schistosomal infection with artemether

An early treatment with artemether given in appropriate regimens was tested in mice, rabbits and dogs for prevention purposes. Artemether was administered intragastrically (ig) to the hosts on day 7 after infection with Schistosoma japonicum cercariae at a single dose, and the same dose of artemether was repeated every 1 or 2 weeks for 2-4 times. As a result, most of the female worms were killed before their oviposition with female worm reduction rates of 90-100%, resulting in protection of the host from damage induced by schistosome eggs. When rabbits were treated ig with artemether 10 mg kg-1 on day 7 after infection, followed by repeated dosing every week for 4 times, some parameters related to acute schistosomiasis, such as temperature, eosinophil count and eggs in the feces were negative, and low specific antigen and antibody levels in serum were seen. Further study showed that the appropriate regimens of Artemether were also effective in early treatment of reinfection with cercariae. When rabbits infected with 48-52 cercariae once every other day for 5 times were treated ig with artemether 15 mg kg-1, followed by repeated dosing every 1 or 2 week for 2- 3 times, the female worm reduction rates were 92.1-98.4%. Histopathological examination of the livers showed that the above-mentioned early treatment with Artemether exhibited a promising protective effect on dogs and rabbits. The major features included normal appearance of the liver resembling those of uninfected dogs and rabbits; few or no dispersed miliary egg tubercles appeared on the surface of the liver; the structure of the hepatic lobules was normal with normal arrangement of the liver bundles; few or no eggs appeared in the portal vein area and there was apparent diminution of total egg granuloma, comprising inflammatory, fibrous or scarred egg granuloma. On the basis of above-mentioned results, early treatment with Artemether could be recommended for field trial for controlling acute schistosomiasis, reducing infection rate and intensity of infection.

Discovery and study of Leishmania turanica for the first time in China

Reported are the results of multidisciplinary studies on Leishmania turanica, which was isolated from the auricular tissues of naturally infected great gerbils in Xinjiang, China. Discussed are the biology of the parasite, its molecular biology, its pathogenicity in rodents and humans and its vectors. This was the first time that L. turanica had been reported in China. L. turanica is highly pathogenic in BALB/c mice, with the resulting systemic infection being lethal, and it causes dermal lesions in Meriones unguiculatus. L. turanica parasitizes the macrophages in the interstitium of the testes of Cricetulus barabensis, and entirely destroys the Leydig's cells of severely infected animals. Inoculation of L. turanica can induce simian and human cutaneous leishmaniasis. The cell membrane and flagella of the promastigotes of L. turanica have rather active ACPase. The major vectors of L. turanica were Phlebotomus mongolensis and P. andrejevi.

Effects of benzimidazole compounds on mice infected with secondary cysts of Echinococcus granulosus

The effects of mebendazole (Meb), albendazole (Alb) and albendazole sulfoxide (AlbSO) on metacestodes of Echinococcus granulosus have been studied. The results show that Meb and Alb exhibit less effect on protoscoleces in vitro, but in vivo the protoscolicidal effect of Meb is higher than that of Alb. Both Meb and Alb are efficacious in the treatment of mice infected with secondary cysts of E. granulosus. In terms of the minimal effective dose required, the occurrence of collapsed and shrunk cysts after treatment, the drug-induced damage on the germinal layer and the relationship between the drug content in the cyst wall and the damage of germinal layer, the effect of Meb on metacestodes of E. granulosus is higher than that of Alb. The results also indicated that lower drug absorption rate and thickening of the adventitia during longer disease course are the two major factors affecting the efficacy of Meb and Alb, hence suggesting that increase of Meb absorption may be expected to raise the therapeutic effect of the drug. Finally, Alb is not only metabolized to AlbSo and AlbSP in vivo, but also metabolized by the cysts exposed to Alb in vitro. Experimental chemotherapy showed that AlbSO is the major effective metabolite of Alb, and its curative dose is only one half of the parent compound.

Binding of platelet-activating factor to oviductal membranes during early pregnancy in the rabbit

The present study explores the ability of rabbit oviductal membranes to bind tritiated platelet-activating factor [3H]PAF on days 3 and 6 of pregnancy. Under optimal conditions (25 degrees C, 120 min) equilibrium saturation analysis revealed only one class of binding sites, characterized by Kd s(nM), 80.03 +/- 11.60 and 11.17 +/- 7.09 and Bmaxs, (pmol/mg protein), 5.25 +/- 2.23 and 1.08 +/- 0.22 (N = 3, mean +/- SEM) for ampullar membranes on days 3 and 6, respectively. The corresponding values for isthmic membranes were Kds, 86.56 +/- 12.01 and 52.43 +/- 30.49 and Bmaxs, 9.41 +/- 0.67 and 2.88 +/- 1.96 for days 3 and 6, respectively. Significant differences between days 3 and 6 were observed only in the binding affinities for the ampullar membranes and the binding capacities for the isthmic binding sites. [3H]PAF binding was inhibited in the following order of decreasing potency: lyso-PAF greater than PAF C18:0 greater than U66985 greater than PAF C16:0 for day 3 ampullar membranes; and lyso-PAF C16:0 greater than PAF C18:0 greater than U66985 greater than PAF C16:0 for day 6 ampullar membranes. These studies show the existence of specific oviductal membrane PAF binding sites, the binding parameters of which may be related to the stage of pregnancy, rather than to the spatial location along the oviduct. The relative proportion of endosalpinx to myosalpinx between the ampulla and isthmus may have masked inherent differences and account for the relatively low affinity binding. The physiological significance of oviductal membrane PAF binding is yet to be established.

[Effect of mebendazole, albendazole and albendazole sulfoxide on glycogen contents of Echinococcus granulosus cysts in infected mice]

Mice infected with protoscoleces of Echinococcus granulosus for 8-9 months were treated ig with mebendazole (Meb) 50 mg.kg-1.d-1, albendazole (Alb) 300 mg.kg-1.d-1 or albendazole sulfoxide (AlbSO) 150 mg.kg-1.d-1 for 1-7 d. The glycogen contents of cyst wall in each drug groups were 1.0 +/- 0.6 - 1.8 +/- 0.9 mg/g, 1.1 +/- 0.9 - 1.8 +/- 0.8 mg/g and 0.8 +/- 0.5 - 1.5 +/- 0.9 mg/g, respectively, which were less than those 2.2 +/- 1.3 - 2.8 +/- 1.3 mg/g of corresponding control groups with respective glycogen reduction rates of 38-55%, 36-51% and 46-62%. After prolongation of treatment course to 10-14 d, the glycogen contents of cyst wall in Meb and AlbSO groups were further decreased, which resulted in glycogen reduction rates of 73% and 69%, respectively. No further decrease of glycogen contents in Alb groups was seen as the glycogen reduction rates sustained in 32%. Histochemical observation showed that the glycogen contents in germinal layer of the cysts decreased significantly or even disappeared during the treatment of Meb, Alb or AlbSO. The results suggested that the effects of Meb and AlbSO on mice infected with secondary cysts of E granulosus were superior to Alb as evaluated by glycogen reduction rate of cyst wall.

RU 486 interferes with egg transport and retards the in vivo and in vitro development of mouse embryos

Oral administration of RU 486 at 100 mg/kg BW/day to mice on Days 1 and 2 of pregnancy caused retention of embryos in the oviduct and expulsion of those having entered the uterus. The treatment also retarded the development of embryos. In vitro study showed that RU 486 reduced the percentage of 2-cell mouse embryos developing into blastocysts. Thus, in addition to interfering with egg transport and impairing embryonic development in vivo, RU 486 can act directly on the embryo, interfering with preimplantation development in vitro.

[Uptake and distribution of [3H]praziquantel in Echinococcus granulosus cysts]

[3H]Praziquantel was absorbed rapidly by the cysts in mice infected with metacestodes of Echinococcus granulosus and treated with ig [3H]praziquantel 400 mg/kg (containing 3H 1.48 MBq). Within 24 h after treatment, 3H content in the ectocyst was 27.7-54.9% higher than that in cyst wall. The peak concentration of 3H in cyst wall and cyst fluid were 11.7-15.3% of those found in plasma. However, when the cysts were exposed to [3H]praziquantel 20 micrograms/ml (containing 3H 3.7 kBq), the 3H radioactivity in the cyst wall and cyst fluid reached equilibrium within 30 min-48 h after medication, corresponding to 45.5-63.3% of 3H radioactivity in the medium. Autoradiography showed that [3H]praziquantel entered into the germinal layer through ectocyst and laminated layer. The damage to germinal layer was related closely to deposition of the drug.

[Hemodynamic effects of a water soluble extract of Liriope spicata Lour on anesthetized cats]

The effects of water soluble extract of Liriope spicata on acute hemodynamics were studied in anesthetized cats. The results showed that LV dp/dt max was increased by 87%, whereas t-dp/dt max was shortened by 28% after administration of WSEL (1.75 g/kg, iv). At the same time CO, CI, SI, and SVWI were increased by 146, 151, 153, and 194%, respectively. HR was declined slightly. SVR was reduced by about 48%. WSEL (0.7 g/kg, iv) induced an increase of 38% in LV dp/dt max, 44% in CO, 50% in SI and a decrease of 20% in t-dp/dt max and 20% in SVR. Preliminary results indicated that WSEL increased ventricular contractile force and might increase cardiac pump function.

[A study on the literature on sheng mai powder of past dynasties]

Our study reveals that the earliest historical records of Sheng Mai Powder are found in "Yixue qiyuan" ("Origins of Medicine"), a medical book written by Zhang Yuansu and published in the beginning of 1186, 45 years earlier than the latest edition of "Neiwai shangbian huolun" ("Treaties on the identification of Internal Diseases and External Damages"), written by Li Gao in 1231. The study also suggests that the assertion of Sheng Mai Powder to be inaugurated by Sun Simiao is groundless.

[Effect of praziquantel and albendazole on ultrastructure of protoscolex of Echinococcus granulosus]

When protoscoleces of Echinococcus granulosus, maintained in 20% calf serum-RPMI 1640 were exposed to praziquantel 1 microgram/ml for 1-48 h, severe damages to the ultrastructure of protoscoleces were observed. The main lesions of the tegument included indistinct of the matrix, vacuolization and peeling, while vacuolization of perinuclear cytoplasma in tegumental cells, focus lysis in muscle bundles, and destruction in collection ducts and flame cells were also seen. The results suggest that the damages to the tegument, collection ducts and flame cells may interfere with the nutrition and defence functions of protoscoleces, and destroy the osmoregulatory system, which may be the major causes of death in protoscoleces during treatment with praziquantel. When protoscoleces were exposed to albendazole 20 micrograms/ml for 24-72 h, no apparent damage to the tegument was detected, except that some network-like structures appeared in the cytoplasma of tegument and parenchyma cells.

[Light and electron microscopic observations on effects of tribendimidin on cuticle of Necator americanus and small intestinal mucosa of infected golden hamsters]

Golden hamsters infected with Necator americanus were treated orally with a new anthilmintic tribendimidin (N, N'-[bis-4'-(1-dimethyl amino ethylidene amino)phenyl] 1,4-phenyene dimethylidyne amine) at a single dose of 150 mg/kg. One h after medication, some worms showed cuticular swelling, fusion of transverse striations and attachment of host leucocytes onto the worm's damaged cuticular surface. Four h post treatment, the cuticle revealed a moderate swelling or even erosion. Meanwhile, the ventral cutting plates appeared to be swollen. After 8-24 h, severe cuticular swelling, erosion and peeling in female worm tails and male copulatory bursa were seen. No increases in lesions in the small intestinal mucosa of infected golden hamsters were observed 4-8 h after medication.