Biomedical subjects

Y P Shen

Publications and source records attributed to Y P Shen.

14 recordsLinked to original sources

PubMed1997

[The expression of Quox-1 gene homologous sequence in the development of early human embryos].

By using the b2 fragment of Quox-1 gene as probe, we have confirmed that the Quox-1 gene homologous sequence exists in the human genome according to the results of Southern blot. Studies on the expression of Quox-1 homologous sequence in early human embryos from 26 to 37 days by means of immunohistochemistry technigue with Quox-1 protein antibodies showed the spatiotemporal expression patterns: in 26 days embryo Quox-1 homologous sequence was expressed in many places including neural tube, but 30 days later, tits expression sites were limited to notochord, digestive epithelium, myotome, cardiac muscle cell and periderm. The functions in control and regulation of Quox-1 gene homologous sequence during the early development of human embryo were discussed.

Animals↗

PubMed1994

[Effect of combined chemotherapy against human intestinal nematode eggs].

The effect of a combination of albendazole and mebendazole was evaluated by stool examination in 7 patients with Ascaris lumbricoides eggs, 7 patients with Trichuris trichiura eggs and 9 patients with hookworm eggs. Albendazole and mebendazole were given at 300 mg and 375 mg, respectively. Both drugs were divided into 3 parts, one part b. id., and given in 1.5 days. The fecal eggs turned negative in all the patients with Ascaris infection in 3 days, while the fecal eggs were negative in all patients with Trichuris or hookworm infection in 5 days. The development rates of the eggs were remarkably lower post-treatment than pre-treatment. It was found that the ovicidal rates in human ascariasis, trichuriasis and ancylostomiasis were 98.8%, 100% and 100%, respectively on the second day following the initiation of treatment. The results showed that the worm-repelling and ovicidal effect of the combined chemotherapy was more evident.

Adolescent↗

PubMed1993

[Studies on the changes in infection rates of whipworm and ascaris in population after continuous chemotherapy].

The inhabitants with positive eggs of whipworm and ascaris in a village of Jiangdou County were examined and treated with different antihelmintic drugs twice a year. The uncured population were treated by drug administration once again. On an average the efficiency of drug treatment (cure rate x treatment rate) was 56.7% in whipworm and 64.5% in ascaris. The program had been carried out for five years. The positive rate of eggs of whipworm and ascaris in the population decreased from 64.7% and 52.1% to 2.7% and 4.1%, respectively, the mean increase in infection rates among population at 5 or 7 months after treatment was 2.68 (0.86-5.74)% and 6.94(1.72-17.27)%, respectively.

Albendazole↗

PubMed1991

Characterization of stage-specific antigens of Paragonimus westermani.

In order to develop a serodiagnostic assay to detect antigens of Paragonimus westermani in biological specimens, we generated monoclonal antibodies to antigens of metacercariae and adult worms, and partially characterized the epitopes recognized by representative Mabs. Metacercarial stage-specific determinants were periodate-sensitive and protease-resistant, indicating that they are carbohydrate epitopes. In contrast, adult worm-specific determinants resisted periodate treatment but were sensitive to proteases, indicating that they are polypeptides. The majority of cross-reactive Mabs studied were directed against phosphorylcholine determinants. When used in a dot-ELISA, Paragonimus-specific Mabs could detect 0.3-7 ng/ml parasite antigen in human sera.

Animals↗

PubMed1990

Synthesis of a trehalose homolog, 6-deoxy-alpha-D-gluco-heptopyranosyl 6-deoxy-alpha-D-gluco-heptopyranoside, and the corresponding bis(heptosiduronic acid).

Crystalline 6-deoxy-alpha-D-gluco-heptopyranosyl 6-deoxy-alpha-D-gluco- heptopyranoside (8) and (6-deoxy-alpha-D-gluco-heptopyranosyluronic acid) 6-deoxy-alpha-D-gluco-heptopyranosiduronic acid (7) were synthesized from alpha, alpha-trehalose (1). Reaction of 2,3,4,2',3',4'-hexa-O-acetyl- 6,6'-di-O-tosyl-alpha, alpha-trehalose with sodium dicarbonylcyclopentadienyliron, followed by oxidative hydrolysis or methanolysis, gave the 2,3,4,2',3',4'-hexa-acetate of 7 or its dimethyl ester, respectively. O-Deacetylation (Zemplén) then gave 7 and its dimethyl ester. Reduction of the hexa-O-acetyldicarboxylic acid with borane-oxolane complex yielded 8. Alternatively, cyanide displacement of hexa-O-acetyl-alpha, alpha-trehalose 6,6'-ditriflate gave the dinitrile hexa-acetate of 7, which was O-deacetylated and then hydrolyzed with alkaline hydrogen peroxide to yield 7. 2,3,4,2',3',4'-Hexa-O-benzyl-alpha, alpha-trehalose 6,6'-ditriflate was similarly converted into the dinitrile, which was hydrolyzed to the corresponding diamide. Treatment of the 2,3,4,2',3',4'-hexa- O-acetyl-alpha, alpha-trehalosuronic acid 16 with thionyl chloride followed by diazomethane gave a crystalline bisdiazoketone which, however, failed to produce the expected bis(heptosiduronic acid) on attempted Wolff rearrangement.

Acetylation↗

PubMed1990

[Clinical observations on the treatment of hookworm, Ascaris and Trichuris infection with oxibendazole].

340 cases of hookworm infection, 196 cases of ascariasis and 178 cases of trichuriasis were treated with an anthelmintic, oxibendazole, 15mg/kg.d x 3d; 102, 70 and 66 cases of respective infections were treated with pyrantel 10mg/kg.d x 3d and 108, 74 and 63 cases took placebo for comparison and as control under double-blind observations. Re-examinations of the stool were performed after the treatment. Among the cases treated with oxibendazole, the egg negative conversion rates of hookworm, Ascaris and Trichuris were 70.3-80.6%, 92.5-97.8 and 67.0-71.0% respectively. The egg reduction rates of hookworm were 98.1-98.6%. The larval negative conversion rates of Ancylostoma duodenale and Necator americanus were 77.7 and 83.2% respectively. Among the cases treated with pyrantel, the egg negative conversion rates of the three above mentioned parasites were 73.5, 90.0 and 28.8% respectively. The egg reduction rate of hookworm was 98.8%. Among the cases treated with placebo, the egg negative conversion rates of the three above mentioned parasites were 6.5, 29.7 and 7.9%. No marked adverse reactions were observed by clinical and laboratory examinations.

Animals↗

PubMed1990

Studies on specific serological antigens in metacercariae and juveniles of Paragoniums westermani and its monoclonal antibodies.

The polyclonal antibodies to juveniles of Paragoniums westermani (PwJ-PcAbs) from sera of Wistar rats infected with Paragoniums westermani (P.w.) were purified by Sephadex G 200 chromatography. Next the shared serological antigens of P.w. metacercaria and juveniles (PwMJ-SAg) from the crude antigens of the metacercariae (M-NS-Ag) were purified with immuno-affinity chromatography on cyanogen bromide-activated cross-linked Sepharose 4B beads coupled with PwJ-PcAbs. PwMJ-SAg, a group of glycoprotein molecules shown by the staining test, were specific serological antigens of P.w. metacercariae and juveniles, identified by the immunoabsorb test and immunoelectrophoresis. By SDS-PAGE, PwMJ-SAg were fractionated to seven bands, including major bands A (27.5 K) and Bi (19.5 K), the two major serological antigen molecules. 20 sera samples from the patients with the nonpulmonary type of P. w. paragonimiasis were detected using PwMJ-SAg and M-NS-Ag by Dot-ELISA, and the difference of sensitivity between two antigens was highly statistically significant (P less than 0.001). BALB/c mice, in the early stage of infection with P. w. metacercaria, were immunized with PwMJ-SAg. The spleen cells of the mice were isolated and fused with SP2/o, a murine myeloma cell line. After three subclonal cultures, eight cell lines secreting monoclonal antibodies (McAbs) to PwMJ-SAg were prepared from 384 wells of hybridoma cells. All McAbs were IgG1 subclass.

Animals↗

PubMed1989