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Biomedical subjects

Y L Su

Publications and source records attributed to Y L Su.

At least 19 recordsLinked to original sources
PubMed2000

[Longitudinal observation on the control of intestinal helminthiasis].

OBJECTIVE: To search suitable measure for rapid control intestinal helminthiasis and long-term strengthen efficacy. METHODS: The treatment was taken in egg-positive population of intestinal helminthiasis in 1986-1988. The treatment was carried out only in the selected population in 1989-1992. No measure was taken in 1993-2000. RESULTS: (1) The prevalence rate of hookworm, Ascaris and Trichuris decreased to 3.2%, 37.3% and 3.5% respectively after administration of albendazole twice a year for 3 years. (2) The prevalence rate of hookworm continued to decrease to 0.5% after treatment on selected population. (3) The prevalence rate and the intensity of hookworm has been less than 1% and 10/LPG for 8 years. No hookworm larvae had been isolated from the soil. CONCLUSION: The hookworm transmission was effectively controlled in the study site.

Albendazole↗
PubMed1999

Endothelium-dependent contraction and direct relaxation induced by baicalein in rat mesenteric artery.

The vascular effect of purified baicalein from Scutellaria baicalensis Georgi (Huangqin) was examined in rat isolated mesenteric arteries. Baicalein exerts both contractile and relaxant effects on the U46619-, phenylephrine- or high K+-contracted endothelium-intact arteries. In endothelium-denuded arteries, the contractile response to baicalein (0.3-10 microM) was absent while the relaxant response to baicalein (30-300 microM) remained. Pretreatment with 100 microM N(G)-nitro-L-arginine (L-NNA) or 3 microM methylene blue abolished the baicalein-induced contraction while 10 microM indomethacin or 100 nM BQ610 had no effect. Pretreatment with baicalein (3-10 microM) significantly attenuated the relaxation induced by acetylcholine or by A23187. In contrast, baicalein did not affect the sodium nitroprusside-induced relaxation in endothelium-denuded arteries. Baicalein also concentration dependently inhibited the contractile response to 1 microM phorbol 12,13-diacetate (PDA) in Ca2+-free solution. Baicalein had little effect on the contractile response to 60 mM K+ or to 10 mM caffeine in endothelium-denuded arteries. The baicalein-induced relaxation was unaffected by 1 microM glibenclamide or by 3 mM tetraethylammonium ions in endothelium-denuded arteries. These results indicate that baicalein at low concentrations caused a contractile response and inhibited the endothelium-dependent relaxation, probably through inhibition of endothelial nitric oxide (NO) formation/release. At higher concentrations, baicalein relaxed the arterial smooth muscle partially through inhibition of the protein kinase C-mediated contractile mechanism.

Animals↗
PubMed1997

The chromosomal effect of birchen dust as determined by the micronucleus test.

In a wood processing factory, the measured air concentration of birchen dust was 1.26 +/- 0.41 mg/m3, and the micronucleus frequency of peripheral blood lymphocytes in 83 workers exposed to wood dust was 1.13 +/- 2.83/1000, which was significantly higher (P < 0.01) than that of control group (0.51 +/- 1.41/1000). The number of exposed workers with positive micronucleus test was 9.6%, which was higher than that of control group (4.5%), but the difference was not significant (P > 0.05). The micronucleus test in mice treated with water extracts of unsteamed and unbaked birchen dust showed that the micronucleus frequencies in all treated groups were significantly higher than that of control group (P < 0.01) and there was also a dose response correlation (r = 0.96, P < 0.0005). The results of steamed and baked birchen dust extracts were significantly lower than those of the unsteamed and unbaked ones at the same doses (P < 0.001). This suggests that when the birchen dust is steamed at the temperature of 100 degrees C for 24 h or baked at the temperature of 80 degrees C, its inducing effect in micronucleus test could be lowered.

Adult↗
PubMed1996

Transfusion-acquired AIDS in Taiwan.

Human immunodeficiency virus type 1 (HIV-1) can be transmitted through blood transfusion. The first transfusion-acquired immunodeficiency syndrome (AIDS) patient in Taiwan was a 46-year-old woman who received two units of whole blood during a hysterectomy at a provincial hospital in 1985. In 1991, she experienced a herpes zoster infection. In March 1993, she had extensive herpetic gingivostomatitis and another herpes zoster attack, and was treated at the same hospital. Two months later, she had oral candidiasis and was treated at a medical center. She was not tested for HIV-1 infection until she developed Pneumocystis carinii pneumonia in June 1993. In February 1994, and developed cytomegalovirus retinitis and died 6 months later. Donor blood given to the patients during the hysterectomy was HIV-1 positive. The donor's HIV infection was discovered in 1991 and he died of AIDS in 1993. As blood centers in Taiwan did not start screening for HIV-1 until January 1988, it is urgently recommended that any individual who received a blood transfusion between 1984 and 1987 in Taiwan and who currently experiences repeated episodes of opportunistic infections have an HIV-1 blood test. The receipt of a blood transfusion between 1984 and 1987 should be listed by the Department of Health as an indication for HIV-1 screening.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Study on micronucleus frequency in peripheral lymphocytes in workers of match factories.

This paper reports the results of the study of micronucleus frequency in peripheral lymphocytes in workers exposed to soft wood dust (poplar and linden wood) in match factories. 298 workers exposed to soft wood dust in three match factories were defined as exposure group and 45 waiters in a restaurant as control group. The frequency of micronucleus in peripheral lymphocytes was examined and the control's 95% confidential upper limit >, 4/1000 was defined as the standard to determine the positivity. The positive rate in the exposure group was 36.2% while that in the control group was only 4.4%; the difference is significant (P < 0.01). As the coefficient of correlation between length of work and positive rate was 0.86 (P < 0.01), a dose/time-response is in existence. Meanwhile, the analysis of relation between quantity of smoking and positive rate eliminated the effect of smoking on variation of positive rates. In this paper, we also discussed the relation between positive rates and wood dust concentrations in different worksites and we think that the volatile and unsteady substances in soft wood dust are micronucleus-inducing matters.

Dust↗
PubMed1993

[Studies on the chemical constituents of Desmodium styracifolium (Osbeck) Merr].

A new alkaloid, named desmodimine, C12H15NO4, gum, and a new natural product, named desmodilactone, C8H13NO3, mp 84-85 degrees C have been isolated from the aerial parts of Desmodium styracifolium (Osbeck) Merr. belonging Leguminosae. On the basis of spectral analysis their structures were deduced as formula I and II. In addition, lupenone (III), lupeol (IV), tritriacontane (V), stearic acid (VI), eicosanoic acid eicosyl ester (VIII) and beta-sitosterol (VII) were isolated for the first time from this plant.

Drugs, Chinese Herbal↗
PubMed1992

[Clinical observation on efficacy of ivermectin in the treatment of intestinal nematode infections].

A total of 166 cases were divided into 3 groups: group A comprised 55, group B 54 and group C 57 cases. Group A received ivermectin 0.1 mg/kg orally at a single dose, the cure rates were 100%, 3.8% and 50% for ascaris, hookworm and trichuris, infections respectively: group B received ivermectin 0.2 mg/kg orally at a single dose, the corresponding cure rates were 95.5%, 11.8% and 76.5% respectively; group C received pyrantel pamoate 10 mg/kg orally at a single dose, the corresponding cure rates were 95.5%, 29.6% and 31.6% respectively. Although the cure rates were very low for hookworm infection in both group A and B, however, a number of adult worms of Ancylostoma duodenale and Necator americanus were expelled aster medication; It indicates that ivermectin has some effects on these two species of human hookworm. Side effects were mild and transient in all groups.

Adolescent↗
PubMed1992

[Triterpene constituents from Euphorbia nematocypha Hand-Mazz].

Seven triterpenoids have been isolated from the roots of Euphorbia nematocypha Hand-Mazz. through chromatography on 20% AgNO3-silica gel. One of them was identified as a new compound named nematocyphol on the basis of spectral data (IR, EIMS, 1H-NMR and 13C-NMR). Its structure was deduced as IVa. Other compounds were identified as nepehinol acetate (I), germanicol acetate (II), euphol (III), tanaxastanol (Va), 24-methylenecycloartanol (VIa) and nepehinol (VIIa). These compounds were obtained for the first time from this plant.

Drugs, Chinese Herbal↗
PubMed1991

Studies on the control of hookworm and other soil-transmitted helminthiases in farmers in Zhejiang Province, China.

Different periodic selective chemotherapeutic schemes were used to control hookworm and other soil-transmitted helminthiases in eight villages in five counties in Zhejiang Province, China, 1985-1988. The results showed that the prevalence rates of hookworm, ascariasis, and trichuriasis decreased from 35.0-74.4%, 47.0-.76% and 22.9-47.5% to 3.2-15.8%, 9.9-47.8%, and 3.5-31.2%, respectively, using pyrantel pamoate (10 mg/kg for 1-2 days) or albendazole (400 mg for 1-2 days, once or twice a year for 2-3 years). The eggs per gram of feces of hookworm and Trichuris trichiura also dropped markedly after control. Moreover, the mean hemoglobin levels of sampled populations increased after several treatments. The authors recommend periodic selective chemotherapy as the main method to control soil-transmitted helminthiases, especially hookworm infections.

Agriculture↗
PubMed1991

[Chemical constituents of Armillaria mellea mycelium. VII. Isolation and characterization of chemical constituents of the acetone extract].

Eight compounds were isolated from the acetone extract of artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.)Quel.(Tricholomataceae). Three of them are protoilludane sesquiterpenoid aromatic esters. Their structures were elucidated by spectral data analysis as the known 4'-methylmelledonal (I)and two new compounds named armillaritin (II) and armillarivin (III). In addition, five known compounds were identified as D-erythritol, D-mannitol, azelaic acid, orsellinic acid and glycerin-alpha-monooleate.

Agaricales↗
PubMed1990

[Studies on the chemical constituents of Aquilaria sinensis (Lour.) Gilg. V. Isolation and characterization of three 2-(2-phenylethyl) chromone derivatives].

Three 2-(2-phenylethyl) chromone derivatives were isolated from the ethyl acetate soluble fraction of the alcoholic extract of Aquilaria sinensis (Lous.) Gilg. (Thymeleaceae) by silica gel chromatography. Based on spectral data (UV, IR, 1HNMR, 13CNMR and MS) two of them are new compounds and their structures were identified as 5,8-dihydroxy-2-(2-p-methoxyphenylethyl) chromone (2) and 6,7-dimethoxy-2-(2-p-methoxyphenylethyl) chromone (3). The known compound siolated for the first time from this plant, was identified as 5,8-dihydroxy-2-(2-phenylethyl)-chromone (1).

Chemical Phenomena↗
PubMed1990

[Chemical constituents of Armillaria mellea mycelium. VI. Isolation and structure of armillaripin].

A new protoilludane sesquiterpenoid aromatic ester, named armillaripin, C24H30O6, mp 202-204 degrees C, [alpha]D15 + 130 degrees (c 0.055, CHCl3), was isolated from the petroleum ether extract of the artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel. (Tricolometaceae) by silica gel chromatography. On the basis of spectral (UV, IR, 1HNMR 13CNMR and MS) analysis its structure was deduced as I and confirmed by single-crystal X-ray analysis.

Agaricales↗
PubMed1990

[Studies on the chemical constituents of Armillaria mellea mycelium. V. Isolation and characterization of armillarilin and armillarinin].

Two new protoilludane sesquiterpenoid aromatic esters, armillarilin C24H30O7, mp 179-180 degrees C, [alpha]D14 + 162 (c 0.97 CHC1(3] and armillarinin C24H29O7 C1, mp 152-155 degrees C, [alpha]D17 + 153.6, (c 0.09, CHC1(3], have been isolated from the artifically cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel (Tricholometaceae). On the basis of spectral (UV, IR, 1HNMR, 13CNMR and MS) analysis their structures were identified as I and II, respectively.

Agaricales↗
PubMed1989

Localization of immunoreactive thymosin alpha 1 in astrocytes of normal human brain.

We employed an immunocytochemical method to examine human brain for the presence of immunoreactive thymosin alpha 1 (T alpha 1), a peptide derivative of thymic tissue, using a well-characterized antiserum. For cell identification, serial sections were stained with antisera to thymosin beta 4(T beta 4), another thymic peptide that identifies oligodendrocytes, and with anti-glial fibrillary acidic protein (GFAP) antiserum that stains astrocytes in a double-staining technique using avidin-biotinylated horseradish peroxidase or avidin-biotinylated alkaline phosphatase complex. Antiserum to T alpha 1 stained the cell body, but not the processes, of GFAP-positive astrocytes, suggesting that T alpha 1 is a common antigen shared between thymus and astrocytes. Because T alpha 1 and its precursor molecule play a role in cell proliferation and immunomodulation, our findings could explain the role of astrocytes in certain central nervous system diseases.

Adult↗
PubMed1989

[Studies on the chemical constituents of Aquilaria sinensis(Lour.) Gilg. IV. Isolation and characterization of 2-(2-phenylethyl)chromone derivatives].

Six chromone derivatives were isolated from the ether soluble fraction of the alcoholic extract of Aquilaria sinensis(Lour.) Gilg. (Thymeleaceae) by silica gel chromatography. On the basis of spectrometric data (UV, IR, 1HNMR and 13CNMR as well as MS) and chemical synthesis one of them was found to be a new chromone, 6-hydroxy-2-[2-(4'-methoxylphenyl)ethyl]chromone(VI) and the other five known chromones are 2-(2-phenylethyl)chromone(I), 6-methoxy-2-(2-phenylethyl)chromone (II), 6.7-dimethoxy-2-(2-phenylethyl)chromone(III), 6-methoxy-2[2-(3'-methoxyphenyl)ethyl]chromone(IV) and 6-hydroxy-2-(2-phenylethyl) chromone(V). These compounds were obtained for the first time from this plant.

Chemical Phenomena↗
PubMed1989

[Studies on the chemical constituents of Aquilaria sinensis (Lour) Gilg. III. Elucidation of the structure of isobaimuxinol and isolation and identification of the constituents of lower boiling fraction of the volatile oil].

A new sesquiterpenoid, named isobaimuxinol, C15H26O2, mp 73-75 degrees C, [a]D12-68(0) (c 0.10, CHCl3), was isolated from the volatile oil of Aquilaria sinensis (Lour), Gilg. (Thymeleaceae). Based on spectral (IR, 1H-NMR, 13C-NMR and 2D-NMR as well as MS) analysis its structure was identified as isobaimuxinol. The relative stereochemistry of isobaimuxinol was determined by X-ray crystallograhy. In addition, four known compounds, benzylacetone, p-methoxybenzylacetone, anisic acid and beta-agarofuran were isolated and identified from the lower boiling fraction of the volatile oil of this plant. These compounds were obtained for the first time from this plant.

Chemical Phenomena↗