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Biomedical subjects

X Y Zeng

Publications and source records attributed to X Y Zeng.

At least 19 recordsLinked to original sources
PubMed2002

Effects of active immunization against GnRH on serum LH, inhibin A, sexual development and growth rate in Chinese female pigs.

Surgical castration of young female pigs is common practice in Chinese pig farming today. The purpose of the present study is to investigate anti-GnRH immunization as a practical alternative to surgical castration for female pigs. Thirty-six Chinese female crossbred pigs (Chinese Yanan x Yorkshire) were selected from 12 litters, three pigs from each litter, at the age of 10-13 weeks. One pig from each litter was immunized with 62.5 microg D-Lys6-GnRH-tandem-dimer peptide conjugated to ovalbumin in Specol adjuvant at Week 0 (0 week post-vaccination, wpv), and a booster vaccination was given 8 weeks later (8 wpv). Its intact and castrate littermates (surgically castrated at the time of weaning, i.e. at 6 weeks of age) were administered the vehicle and served as controls. Antibody titers, serum LH and inhibin A were determined at the day of first vaccination, every 4 weeks thereafter and at the day of slaughter (18 wpv). At slaughter, ovaries were inspected for the presence of follicles and corpora lutea, and ovarian and uterine weights were recorded. Ten of twelve immunized pigs responded well to the immunization (immunocastrated animals), while the remaining two pigs responded poorly (nonresponders). Antibody titres in immunocastrated animals steadily increased after immunization, became maximal at 12 wpv and remained high until slaughter. Serum LH levels were reduced (P < 0.05) in immunocastrated pigs as compared to intact controls and surgical castrates. Serum inhibin A levels decreased after vaccination, and equaled surgical castrate levels from 8 wpv until the end of the experiment. Ovarian and uterine weights (1.3 +/- 0.2 and 43.9 +/- 11.4 g, respectively; mean +/- S.E.M.) were significantly lower (P < 0.05) in immunocastrates than in intact controls (9.4 +/- 1.1 and 390.9 +/- 67.2 g, respectively). Antibody titers were significantly lower (P < 0.05) in nonresponders than in immunocastrated pigs from 12 wpv to slaughter. Ovarian and uterine weights were similar in nonresponders and in intact controls. Macroscopically, no follicular structures were found in ovaries of immunocastrated pigs, while large follicles or corpora lutea were observed in the ovaries of both nonresponders and intact controls. Although not significant, immunocastrates had a numerically higher average daily gain than surgical castrates and intact controls (0.74 +/- 0.04 versus 0.66 +/- 0.04 versus 0.66 +/- 0.03 kg per day, respectively; mean +/- S.E.M., P = 0.09). Results obtained in the present study demonstrate that anti-GnRH immunization can be an attractive alternative to surgical castration for Chinese crossbred female pigs. Our results also question the beneficial effect of surgical castration on growth as compared to intact controls.

Animals↗
PubMed2001

Studies on the clinical efficacy and pharmacokinetics of low-dose arsenic trioxide in the treatment of relapsed acute promyelocytic leukemia: a comparison with conventional dosage.

Twenty cases of patients with relapsed acute promyelocytic leukemia (APL) were entered into this study for evaluating the clinical efficacy and pharmacokinetics of low-dose arsenic trioxide (As2O3). As2O3 was given at a daily dose of 0.08 mg/kg intravenously for 28 days. Pharmacokinetic study was carried out in eight patients. 16/20 (80%) patients achieved CR. The occurrence of some toxic events including gastrointestinal disturbance, facial edema and cardiac toxicity seemed reduced in the low-dose group than those in the standard-dose group. Differentiation changes were observed in peripheral blood, as well as in bone marrow (BM). Pharmacokinetic study showed that the plasma concentration increased soon after administration of As2O3 with the peak values of 1.535-3.424 micromol/l. After infusion, the plasma concentration was around 0.1-0.5 micromol/l. The arsenic concentration of the plasma of BM aspirates 24 h after administration in five patients was close to the level needed for differentiation-inducing effect. The estimated 2-year OS and RFS were 61.55+/-15.79% and 49.11+/-15.09% respectively, with no difference as compared with those in patients treated with conventional dose (P = 0.2865 and 0.7146, respectively). In conclusion, we demonstrated that low-dose As2O3 had the same effect as the conventional dosage and the mechanism of low-dose arsenic seemed to primarily induce differentiation of APL cells.

Adolescent↗
PubMed2001

Active immunization against gonadotrophin-releasing hormone in Chinese male pigs.

We have investigated, under the normal conditions of local Chinese pig farming, castration of young male pigs by vaccination with a newly developed vaccine against gonadotrophin releasing hormone (GnRH). Because of the very early onset of puberty, long fattening period and relatively harsh circumstances in Chinese pig production, an investigation of the endocrine response of Chinese breeds to this type of vaccination was of particular interest. Fifteen crossbred boars (Yorkshire x Yanan) from three different litters were randomly assigned to three groups of five animals each. The first group was immunized at 13 weeks of age with a GnRH tandem dimer OVA-conjugate in Specol and received a booster immunization 8 weeks later. The second group was injected with Specol alone and served as untreated controls. The remaining group was surgically castrated at the time of weaning (at 6 weeks of age). Pigs were fed ad libitum from weaning onwards. All animals were slaughtered at 31 weeks of age. Immunized boars had undetectable or low serum testosterone (0.09 +/- 0.12 ng/ml), low fat androstenone (0.05 +/- 0.01 microg/g) levels and very low testes weights (19.1 +/- 4.3 g). Intact controls had much higher serum levels of testosterone (9.76 +/- 4.81 ng/ml), fat androstenone levels (2.26 +/- 0.87 microg/g) and testes weights (114.3 +/- 29.41 g) at slaughter. Both the immunized and castrated group grew significantly faster than intact boars (p < 0.01). Average daily gains in immunized, castrated and intact animals were 0.69 +/- 0.08, 0.63 +/- 0.05 and 0.42 +/- 0.07 kg (mean +/- SD), respectively. The present data demonstrate for the first time that the newly developed anti-GnRH vaccine works very well under practical Chinese pig farming conditions, and can be an attractive alternative to surgical castration.

Age Factors↗
PubMed2001

Ramosetron for the management of chemotherapy-induced gastrointestinal events in patients with hematological malignancies.

The objective of this study was to evaluate the efficacy and safety of ramosetron hydrochloride for the management of nausea and vomiting induced by chemotherapy in patients with hematological malignancies. A total of 30 patients with hematological malignancies were included in the ramosetron group. Ramosetron (0.3 mg i.v.) was administered 0.5 h before chemotherapy. The impact of ramosetron on anorexia, nausea and vomiting as well as other adverse effects were assessed. Meanwhile, another 39 patients received tropisetron (o.d. for 3 days). As compared to the tropisetron group, the response rate of the ramosetron group in controlling anorexia within 18-24 h after chemotherapy was higher (p < 0.05); within 18-24 h after chemotherapy, the complete response rate and effective rate in controlling nausea was higher (p < 0.05); within 12-18 h and 18-24 h after chemotherapy, the complete response rate and effective rate in controlling vomiting was higher (p < 0.05). The incidence of adverse effects was similar in both groups. We conclude that ramosetron belongs to a new generation of 5-HT3 receptor antagonists and that it is a safe, economic and effective antiemetic drug.

Adolescent↗
PubMed2001

[Determination of organic acids in cigarette smoke].

Solid phase microextraction (SPME) is a simple, cost-effective, time-saving extraction technique. It is rapid and highly sensitive. In this study, organic acids in cigarette smoke were extracted with 85 microns polyacrylate coated fiber. Volatile and semi-volatile organic acids, such as butanoic acid, hexanoic acid, 2-furancarboxylic acid, octanoic acid, nonanoic acid, benzoic acid, phenylacetic acid, tetradecanoic acid, and hexadecanoic acid from cigarette smoke were converted to their esters by using methanolic derivatization agent. The esters were extracted by using headspace solid phase microextraction and determined quantitatively by gas chromatography with selected ion monitoring mode mass spectrometry. Qualitative analysis of 4 brands cigarette smoke demonstrated the usefulness of this analytical technique of volatile and semi-volatile acids in cigarette smoke. More than sixty organic acids were detected by using this method.

Benzoic Acid↗
PubMed2000

Changed cellular membrane lipid composition and lipid peroxidation of kidney in rats with chronic fluorosis.

An animal model of chronic fluorosis was produced by subjecting Wistar rats to high doses of fluoride in drinking water for a prolonged period. Phospholipid and neutral lipid contents in rat kidney were then analyzed by high-performance liquid chromatography (HPLC), and fatty acid compositions from individual phospholipids were measured by gas chromatography. Lipid peroxidation was detected by the thiobarbituric-acid-reactive substance assay. Results showed that the total phospholipid content significantly decreased in the kidney of the rats treated with high doses of fluoride and the main species influenced were phosphatidylethanolamine (PE) and phosphatidylcholine (PC). Decreased proportions of polyunsaturated fatty acids were observed in PE and PC in kidney of fluoride-treated animals compared to controls. No changes could be detected in the amounts of cholesterol and dolichol in kidneys between the rats treated with fluoride and controls. A significant decrease of ubiquinone in rat kidney was observed in the groups treated with excessive fluoride. High levels of lipid peroxidation were detected in kidney of the rats with fluorosis. It is plausible that the specific modification of lipid composition results from lipid peroxidation. The oxidative stress and modification of cellular membrane lipids may be involved in the pathogenesis of chronic fluorosis and provide a possible explanation for the gross system damage observed in the body, especially in soft tissues and organs.

Animals↗
PubMed1999

Studies on treatment of acute promyelocytic leukemia with arsenic trioxide: remission induction, follow-up, and molecular monitoring in 11 newly diagnosed and 47 relapsed acute promyelocytic leukemia patients.

Fifty-eight acute promyelocytic leukemia (APL) patients (11 newly diagnosed and 47 relapsed) were studied for arsenic trioxide (As2O3) treatment. Clinical complete remission (CR) was obtained in 8 of 11 (72.7%) newly diagnosed cases. However, As2O3 treatment resulted in hepatic toxicity in 7 cases including 2 deaths, in contrast to the mild liver dysfunction in one third of the relapsed patients. Forty of forty-seven (85.1%) relapsed patients achieved CR. Two of three nonresponders showed clonal evolution at relapse, with disappearance of t(15;17) and PML-RARalpha fusion gene in 1 and shift to a dominant AML-1-ETO population in another, suggesting a correlation between PML-RARalpha expression and therapeutic response. In a follow-up of 33 relapsed cases over 7 to 48 months, the estimated disease-free survival (DFS) rates for 1 and 2 years were 63.6% and 41.6%, respectively, and the actual median DFS was 17 months. Patients with white blood cell (WBC) count below 10 x 10(9)/L at relapse had better survival than those with WBC count over 10 x 10(9)/L (P =.038). The duration of As2O3-induced CR was related to postremission therapy, because there was only 2 of 11 relapses in patients treated with As2O3 combined with chemotherapy, compared with 12 of 18 relapses with As2O3 alone (P =.01). Reverse transcription polymerase chain reaction (RT-PCR) analysis in both newly diagnosed and relapsed groups showed long-term use of As2O3 could lead to a molecular remission in some patients. We thus recommend that ATRA be used as first choice for remission induction in newly diagnosed APL cases, whereas As2O3 can be either used as a rescue for relapsed cases or included into multidrug consolidation/maintenance clinical trials.

Adult↗
PubMed1996

[Structure of gypentonoside A from Gynostemma pentaphylum Makino].

A new saponin named gypentonoside has been isolated from Gynostemma pentaphylum (Thunb) Makino, C54H88O21, mp 272-274 degrees C. Its structure was established on the basis of chemical and spectroscopic (IR, FAB-MS, UV, 1H-NMR, 13C-NMR, 2D-NMR) analyses.

Cucurbitaceae↗
PubMed1994

[Pharmacological actions of hyphae body of Auricularia auricula (L. ex Hook) Underw and its alcoholic extract].

The percent peripheral blood T lymphocytes were elevated and HC50 reduction induced by cyclophosphamide was recovered after the hyphae body of Auricularia auricula had been ip administered in mice. The action of blood platelet agglutination in rats induced by ADP was inhibited and the time of erythrocytic electrophoresis in mice was shortened after the alcoholic extract had been ig administered.

Animals↗
PubMed1994

[Chemical constituents of Aralia decaisneana Hance].

Six compounds were isolated from the root bark of Aralia decaisneana and elucidated by spectral and chemical analyses as 3-O-[beta-D-galactopyranosyl-(1-->4)-beta-D-galactopyranosyl- (1-->3)-beta-D-glucuronopyranosyl]-oleanolic acid (Ad-V), chikusetsusaponin IVa (Ad-IX), deglucose chikusetsusaponin IVa (Ad-X), palmitic acid (Ad-VI), beta-sitosterol (Ad-VII) and oleanolic acid (Ad-VIII). Ad-V was obtained from nature for the first time, and the rest were all obtained from this plant for the first time.

Drugs, Chinese Herbal↗
PubMed1994

[Chemical constituents of Luffa cylindrica (L.) Roem].

Six compounds were isolated from the fruits of Luffa cylindrica. They were identified as lucyosides C, E, F, H, a mixture of alpha-spinasterol and stigmasta-7,22,25-trien-3 beta-OH and a mixture of alpha-spinasteryl glucoside and delta 7,22,25-stigmasteryl-beta-D-glucoside by means of chemical evidence and spectral analysis.

Drugs, Chinese Herbal↗
PubMed1993

Experimental research on immunological activity of Polyactin A.

Polyactin A is a polysaccharide extracted from cultured alpha-Streptococcus No. 33 in the mouth. It is also known as alpha-glucomannan. According to clinical reports, Polyactin A is considered to be an immunological adjuvant with significant curative effect in chemotherapy of tumors. Immunological activities of Polyactin A were studied. When injected into mice at the dosage of 100 mg/kg for 4-5 consecutive days, Polyactin A can cause a marked increase in spleen weight and RFC in spleen, and it can antagonize the immunosuppressive actions of cyclophosphamide. Polyactin A can also increase phagocytosis of macrophages in the peritoneal cavity of mice. Phagocytotic ratio and phagocytotic index in the experimental group were greater than those in the control group. Phagocytotic ratio and phagocytotic index were respectively 63.5 +/- 8.3% and 1.02 +/- 0.05% in the Polyactin A treated group but were respectively 21.0 +/- 5.7% and 0.3 +/- 0.03% in the control group. The differences were significant (p < 0.05, < 0.01). Polyactin A had definite influence on the transformation test of lymphocytes and increased the transformation ratio of lymphocytes in vitro. The ability of Polyactin A to induce the transformation of lymphocytes into lymphoblasts was almost the same as that of PHA. These results suggest that polyactin A has a marked immunological activity, which is not entirely due to the role of large molecular weight polysaccharide. They provide direct evidence for the assumption that Polyactin A may be an immunological adjuvant, and it is experimentally confirmed that Polyactin A can protect the immunity of the organism.

Adjuvants, Immunologic↗
PubMed1989

[Studies on the immunoregulative action of polysaccharides isolated from hyphal bodies of Lentinnus edodes (PHL) on hypoimmunity in mice].

PHL possesses significant antagonist action for immunodepression in mice induced by different immunodepressors. It can reverse the hypomacrophage function and the reduction in percentage of T-lymphoid cell induced by hydrocortisone (50 or 80 mg/kg, sc), reverse the reduction of phagocytosis of reticuloendothelial system (RES) induced by hydroprednisone acetate (20 and 40 mg/kg, ip), restore the cyclophosphamide-suppressed delayed anaphylaxis reaction in mice (40 and 80 mg/kg, ip). In vitro PHL at a dose of 1 and 10 micrograms/ml accelerated lymphocyte mitosis induced by conA and PHA.

Animals↗