A new and highly sensitive method for measuring 3-methoxytyramine using HPLC with electrochemical detection. Studies with drugs which alter dopamine metabolism in the brain

3-Methoxytyramine (3-MT) is a minor metabolite of dopamine which is suggested to reflect the turnover and utilization of dopamine. A novel, isocratic HPLC method has been developed which can be used to analyse 3-MT in homogenates of rat brain without the need for additional purification procedures. Furthermore, the coulometric electrochemical detection system is sensitive enough to measure 3 pg of 3-MT (equivalent to 0.6 ng/g tissue wet weight). 3-Methoxytyramine was measured in the striatum and n. accumbens after decapitation and rapid freezing, using 3-methoxy-4-hydroxybenzylamine as the internal standard. The effects of dopaminergic and other drugs on this metabolite were examined using this method. -Methyl-p-tyrosine (200 mg/kg i.v.) produced parallel linear decreases in dopamine and 3-MT in naive rats, but not those pretreated with tranylcypromine (5 mg/kg i.p.). Methamphetamine (0.3–10 mg/kg i.p.) and amphetamine (0.3–10 mg/kg i.p.) both dose-dependently increased 3-MT in naive and tranylcypromine-pretreated rats. In naive animals, 3-MT was not altered by intraperitoneal injection of the dopamine reuptake inhibitors, bupropion (10 mg/kg) and nomifensine (10 mg/kg) or by sibutramine HCl (3 mg/kg), amitriptyline (10 mg/kg), desipramine (10 mg/kg) and zimeldine (10 mg/kg). 3-Methoxy-tyramine was decreased by apomorphine (5 mg/kg i.p.) and also by large doses of the selective D₂ antagonist, BRL 34778 (5 mg/kg i.p.) or -DOPA (50 mg/kg i.p.). The selective D₁ antagonist, SCH 23390 (0.1 or 5 mg/kg i.p.) was without effect. In tranylcypromine-pretreated rats, 3-MT was dose-dependently reduced and increased by apomorphine (0.01–5 mg/kg i.p.) and BRL 34778 (0.1–5 mg/kg i.p.), respectively. The drug SCH 23390 (0.1–5 mg/kg i.p.) produced much smaller increases in 3-MT which were probably mediated through the striatonigral pathway. Overall, the data suggest that measurement of 3-MT, after inhibition of monoamine oxidase, is a useful index of the release and utilization of dopamine. However, after substantial and prolonged depletion of dopamine, levels of 3-MT in naive animals are a better index. Also, the formation of 3-MT in naive rats provides a sensitive method for distinguishing between dopamine releasing agents and reuptake inhibitors.     

Periodontal conditions among the middle-aged and the elderly in Hong Kong

Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984.     

液膜法提取发酵液中的苯丙氨酸 Ⅱ.操作工艺条件

从芫花Ｄａｐｈｎｅ ｇｅｎｋｗａ条的乙酸乙酯可溶部分分到３个结果性化合物，借助于波谱分析手段推断出Ⅱ为西瑞香素，Ⅲ为ｄａｐｈｎｏｄｏｒｉｎ Ｂ。     

Susceptibility to ketoconazole of Candida albicans strains from sequentially followed HIV-1 patients with recurrent oral candidosis

The MIC values of the antifungal drug ketoconazole were evaluated on 66 Candida albicans strains. These strains were isolated from 26 HIV-1 infected patients with oral recurrent candidosis. Each episode of oral candidosis observed in these patients was orally treated with ketoconazole (200 mg/day) until the clinical disappearance of the lesions. The most frequent MIC values were 20 micrograms/ml and 10 micrograms/ml, observed in 37 and 19 isolates respectively. Only strains from five patients showed changes in their susceptibility to ketoconazole. This fact could indicate that a different strain causes the subsequent reappearance of the oral lesions, rather than the drug selecting resistant fungal strains. Our results stress the role of host characteristics in the occurrence of candidal infections, pointing to the progressing failure of the immunological response as the most important factor responsible for the recurrence of oral candidosis during HIV-1 infection.     

长泰乐口服液治疗成人急性感染性腹泻45例临床观察

长泰乐生物保健口服液是一种新型腹泻治疗药物，用该药治疗感染性腹泻４５例，与用氟哌酸治疗的对照组比较，结果表明疗效相近，且比后者使用安全。我们认为该药可代替抗生素用于治疗感染性腹泻轻、中型患者，尤其适用于老年、孕妇和儿童。对非感染性腹泻有良好的治疗前景。     

Opitz (BBB/G) syndrome: Oral manifestations

We studied a new case of the G (Opitz BBB/G) syndrome in a 12-year-old boy. Several relatives had partial manifestations of the disorder. A comprehensive dental evaluation of the propositus was conducted; included is, to our knowledge, the first published cephalometric analysis of a G syndrome patient. We reviewed 139 cases of the G syndrome; 48 of them had at least one oral abnormality. These included clefting, micrognathia, ankyloglossia, and high-arched palate. Male G syndrome patients are more likely to have oral anomalies than affected females. © 1992 Wiley-Liss, Inc.     

Reversed-phase high-performance liquid chromatographic method for the assay of 1,4-dioxane in sulphated polyoxyethylene alcohol surfactants

A rapid high-performance liquid chromatographic method has been developed for the assay of 1,4-dioxane in ethoxylated fatty alcohol sulphates. After solid-phase extraction using Bakerbond C₁₈ cartridges, samples were directly analysed on a LiChrospher CH-8 reversed-phase column with UV detection at 200 nm and an acetonitrile-water eluent. Recovery of 1,4-dioxane from the surfactant matrix was 95.7% in the 40 to 120 μg g⁻¹ range. The minimum quantifiable amount was 18 μg g⁻¹. The procedure is simple, reproducible, specific and suitable for routine analyses of commercial surfactants.     

Bioavailability of intramuscularly administered tenoxicam

Bioavailability of intramuscularly administered tenoxicam relative to single oral and relative to intravenous doses was determined in two separate randomized crossover studies. Twelve healthy volunteers (12 males, age 20–30 years) received a rapid intravenous injection and a single intramuscular dose and 12 other subjects (11 males, 1 female, age 21–25 years) a single oral and a single intramuscular dose of 20 mg of tenoxicam on two different occasions. The wash-out period between the two consecutive treatments was 4 weeks. Plasma concentrations after dosing were determined by a specific HPLC method. Differences in tenoxicam concentration-time profiles after the different routes of administration were limited to the first 2 h after dosing. Later, plasma concentrations were almost superimposable within and across the two studies. The extent of absorption of intramuscularly administered tenoxicam was complete (mean ± CV per cent: F_abs 0.99 ± 20 per cent) with no difference between the two extravascular administrations (F_rel 0.95 ± 10 per cent, intramuscular vs oral). After intramuscular administration tenoxicam was more rapidly absorbed compared to the oral dose (T_max 0.71 h ± 80 per cent vs 1.4 h ± 62 per cent; p>0.05). Peak concentrations after oral and intramuscular administration (C_max 2.5 mg 1^?1 ± 19 per cent vs 2.7 mg l^?1 14 per cent; p <0.05) were very similar.     

伤风净喷鼻液体外抗病毒作用的实验研究

目的　观察伤风净喷鼻液在体外的抗病毒作用。方法　先测定药物对细胞的毒性 ,观察细胞病变Cy topathceffect(CPE) ,找出最大无毒浓度 ;再测定流感病毒FM1株、合胞病毒Long株的病毒滴度。最后测定伤风净喷鼻液抑制各病毒对细胞产生细胞病变 (CPE)的作用。结果　实验表明伤风净喷鼻液抗流感病毒FM1株的最低有效浓度为1∶10 2 4,相当于伤风净喷鼻液原药浓度 1.0 5 5mg/ml ,抗合胞病毒Long株的最低有效浓度为 1∶40 96,相当于伤风净喷鼻液原药浓度 0 .2 64mg/ml。 结论　根据实验结果证明伤风净喷鼻液具有明显的抗流感病毒FM1株、合胞病毒Long株作用