Biomedical subjects

Z Y Song

Publications and source records attributed to Z Y Song.

At least 19 recordsLinked to original sources

PubMed2000

[Determination of serumal soluble interleukin-2 receptor levels in patients with tonsillitis].

OBJECTIVE: To observe serumal soluble interleukin-2 receptor levels in patients with tonsillitis. METHOD: SIL-2R levels in serum were detected in 68 patients with acute or chronic tonsillitis and 68 normal controls. RESULT: The SIL-2R concentrations in patients with acute tonsillitis and in patients with chronic tonsillitis within attacking period were (642.2 +/- 87.2) x 10(3) U/L and (762.3 +/- 90.5) x 10(3) U/L, respectively. Both were significantly higher than those of the controls (285.5 +/- 49.6) x 10(3) U/L (P < 0.001). Moreover the latter was higher than the former (P < 0.001). There was no difference between the patients with chronic tonsillitis within non-attacking period and the controls (P > 0.05). After treatment of antibiotics for 3-5 days, the SIL-2R Concentrations in serum in valid cases were obviously becoming lower. CONCLUSION: Determination of SIL-2R in serum was valuable for the diagnosis and curative effect judgement of tonsillitis.

Adolescent↗

PubMed1997

Individual differences in neural sensitization and the role of context in illness from low-level environmental chemical exposures.

This paper summarizes the clinical phenomenology of multiple chemical sensitivity (MCS), outlines the concepts and evidence for the olfactory-limbic, neural sensitization model for MCS, and discusses experimental design implications of the model for exposure-related research. Neural sensitization is the progressive amplification of responsivity by the passage of time between repeated, intermittent exposures. Initiation of sensitization may require single toxic or multiple subtoxic exposures, but subsequent elicitation of sensitized responses can involve low or nontoxic levels. Thus, neural sensitization could account for the ability of low levels of environmental chemicals to elicit clinically severe, adverse reactions in MCS. Different forms of sensitization include limbic kindling of seizures (compare temporal lobe epilepsy and simple partial seizures) and time-dependent sensitization of behavioral, neurochemical, immunological, and endocrinological variables. Sensitized dysfunction of the limbic and mesolimbic systems could account in part for many of the cognitive, affective, and somatic symptoms in MCS. Derealization (an alteration in perception making familiar objects or people seem unfamiliar or unreal) is a common MCS symptom and has been linked with limbic dysfunction in clinical neuroscience research. Sensitization is distinct from, but interactive with, other neurobiological learning and memory processes such as conditioning and habituation (compare adaptation or tolerance). In previous studies, hypotheses for MCS involving sensitization, conditioning, and habituation (adaptation) have often been considered in isolation from one another. To design more appropriate chemical exposure studies, it may be important to integrate the various theoretical models and empirical approaches to MCS with the larger scientific literature on individual differences in these potentially interactive phenomena.

Adaptation, Physiological↗

PubMed1993

[Pharmacokinetics of dihydroqinghaosu in human volunteers and comparison with qinghaosu].

Qinghaosu (QHS), also known as artemisinin and arteannuin, is a novel type of sesquiterpene with a peroxide linkage isolated from the Chinese herb Artemisia annua L. Since its discovery as an antimalarial with low toxicity, hundreds of derivatives have been synthesized among them artesunate (ATS), artemether (ATM) and dihydroqinghaosu (DHQHS) were found to be more active than QHS itself. A suppository of QHS, a dual-pack dosage form of ATS (artesunic acid to be dissolved in sodium bicarbonate solution just before iv injection) and an oil solution of ATM for im injection had been approved by our Ministry of Health for clinical use. However, a preparation for oral administration is still not available. We have reported that when dogs were given QHS tablets orally at the dose of 70 mg/kg, no drug was detected in the serum using the RIA method, whereas appreciable serum concentration was found by the same method when dogs were given DHQHS tablets at a dose as low as 10 mg/kg. This paper reports the pharmacokinetics of DHQHS in man studied with the RIA method and compared with QHS. When DHQHS in tablet form was given to human volunteers at doses of 1.1-2.2 mg/kg, peak serum levels of 0.13-0.71 micrograms/ml were obtained in 1.33 h with MRT of 2.26-2.36 h. When QHS tablets were given at the dose as high as 15 mg/kg, however, the peak serum level found in 1.5 h was only 0.09 microgram/ml with MRT of 1.33 h. Therefore, the bioavailability of QHS tablets is only 1.62-10.08% that of DHQHS.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

PubMed1990

[Use of 2H-labeled compound and GC-MS in the isolation and identification of a metabolite of biphenyldimethyl-dicarboxylate in rat urine].

Dimethyl-4, 4'-dimethoxy-5, 6, 5', 6'-dimethylenedioxy-biphenyl-2, 2'-dicarboxylate (biphenyldimethyldicarboxylate; BDD), a synthetic compound, has been used in the treatment of chronic hepatitis with good results in reducing s-GPT. Previous work in our laboratory studied its metabolites using 3H-labeled compound in combination with TLC and found that its main metabolic pathway is demethylation followed by conjugation with glucuronic acid. This paper reports the isolation and identification of a metabolite of BDD from rat urine using 2H-labeled compound and GC-MS. Rats fasted for 12 h were intragastrically given a mixture of 2H-labeled (consisting of monodeutero- and dideutero-BDD in the ratio about 1:1.3) and non-labeled BDD 150 mg/kg and placed in metabolism cages for urine collection. The 24 h urine was filtered and extracted three times each with 5 ml of methylenedichloride. The extracts were pooled and evaporated to dryness under reduced pressure at 35 degrees C. The residue was redissolved in chloroform and subjected to GC-MS analysis. The mass spectrum (m/z: 404, 405, 406; 373, 374, 375; 345, 346, 347; 330, 331, 332; etc) indicates that the molecular ionic and fragment peaks of the metabolite all have 14 amu less than those of BDD. This means that the metabolite isolated is mono-O-demethylated BDD. The result confirmed our findings reported previously.

Animals↗

PubMed1990

[The pharmacokinetics of dihydroqinghasu given orally to rabbits and dogs].

Qinghaosu (QHS), also known as artemisinine and arteannuin, is isolated from the Chinese herb Artemisia annua L. It is highly active against both chloroquine-sensitive and chloroquine-resistant strains of P. berghei and has been approved by the Ministry of Health for the treatment of malaria. When QHS is treated with sodium borohydride, dihydroqinghaosu (DH QHS) is resulted with the antimalarial activity enhanced several fold. This paper reports the pharmacokinetics of DHQHS studied with the radioimmunoassay method. When the drug was given orally in tablet form to rabbits at doses of 10, 20 and 30 mg/kg, peak serum levels of 0.03, 0.05 and 0.13 micrograms/ml, respectively, were obtained in 1 to 2 h. The corresponding T1/2 of the drug were found to be 1.19, 1.00 and 1.10 h and the MRTs were 1.73, 1.36 and 1.53 h. No significant difference between dosages used was observed. When dogs were given DHQHS tablets at the dose of 20 mg/kg, a peak serum concentration of 0.13 micrograms/ml wes reached in about 2 h with a T1/2 of 2.10 h and an MRT of 3.04 h. However, when dogs were given QHS tablets at the dose of 70 mg/kg, no drug was detected in the serum. It would appear that the bioavailability of DHQHS tablets is much higher than that of QHS when given orally to the dog.

Administration, Oral↗

PubMed1990

[Bioavailability studies on the preparations of biphenyl dimethyl dicarboxylate(DDB)].

Since the bioavailability of the suspension and the tablet of DDB given orally is only 20-30%, we have prepared four kinds of DDB solid dispersion preparations (DDB pilule I with polyethylene glycol 6000 as the vehicle, DDB pilule II with polyethylene glycol 6000 and absorption accelerator as the vehicle, capsule of DDB-urea fusing mixture and DDB-polyvinyl pyrrolidone coprecipitate), and the bioavailability of these preparations were studied in rabbits, rats and human volunteers by HPLC method. All four preparations showed better absorption than the DDB tablet, and the area under serum DDB concentration-time curve of pilule II was 19 fold that of the tablet in rabbits, meaning that the absorption of pilule II is the best of the four preparations. After administration of the four solid dispersion preparations, the fecal excretion of DDB were all lower than the tablet in both animals and human volunteers. The protective action of pilule II against CCl4 hepatotoxicity was about six times stronger than that of the suspensions. Therefore, there are good reasons to use DDB pilule II instead of the tablets of suspension in the clinic.

Animals↗

PubMed1989

[The pharmacokinetics of a transdermal preparation of artesunate in mice and rabbits].

Qinghaosu, also known as artemisinin and arteannuin, is a new type of antimalarial drug isolated from Artemisa annua L. Its low solubility in water and oil limited its widespread clinical use. Artesunate (sodium dihydroqinghaosu hydrogen hemisuccinate monoester) is easily soluble in water and is used iv in the treatment of acute cerebral and malignant malaria. However, artesunate was shown to have a very short half-life when given iv in animals as well as in human beings. A transdermal dosage form of artesunic acid had been prepared and was reported to have reliable suppressing and killing effects on plasmobium berghei in mice. This paper reports results of pharmacokinetic studies of this preparation when applied onto a fixed area of the shaved skin of mice and rabbits. Serum concentration of the drug was determined by a method of radioimmunoassay. The drug was found to be easily absorbed from the skin. The serum concentration-time curve is depicted in figures 1. Peak concentration of 1.8 micrograms/ml was reached at about 2 h when a dose of 25 mg/kg was given to rabbits. For mice, peak serum concentrations of 2.05 and 7.11 micrograms/ml were attained in about 0.5 h after doses of 31.3 and 71.4 mg/kg, respectively, while at a dose of 6.7 mg/kg a peak level of 0.82 micrograms/ml (a concentration more than 5000 times the IC50 of artesunate in in vitro tests on plasmodium berghei for antimalarial activity) was attained at about 4 h after application of the drug. The half-lives of the drug were found to be more than 2 h for both mice and rabbits.

Administration, Cutaneous↗

PubMed1989

Distribution and excretion of artesunate in rats.

The tissue distribution and excretion of artesunate in rats were determined using a radioimmunoassay method. Ten min after i.v. administration of the drug, the highest level was found in the intestine. Levels in other tissues were in the following decreasing order: brain, liver, kidney, testicle, muscle, fat, heart, serum, eyeball, spleen, and lung. However, 1 h after administration, the drug levels dropped significantly in all tissues, but not in the same proportions. High levels remained in the brain, fat, intestine and serum. Drug levels in other tissues were very low. Less than 1% of the dose was found in urine and feces collected during the 24 h period after administration.

Animals↗

PubMed1989