Pharmacokinetics and haemodynamic effects of ISDN following different dosage forms and routes of administration

The pharmacokinetics and haemodynamic effects of isosorbide dinitrate (ISDN) have been investigated following administration of single doses as a sublingual (SL) spray (2.5 mg), sublingual tablet (5 mg) and peroral tablet (10 mg) in a randomised, placebo-controlled double-blind cross-over trial in 16 healthy volunteers.After the sublingual spray C_max was higher (39.0 ng·ml^-1) and t_max was shorter (3.9 min) than after the sublingual (22.8 ng·ml^-1 and 13.8 min) and peroral (16.9 ng·ml^-1 and 25.6 min) tablets. The AUC of ISDN did not differ following any of the three formulations (1031; 879; 997 ng·ml^-1·min, for the spray, SL tablet and PO-tablet, respectively). Mononitrate metabolites of ISDN (IS-2-MN and IS-5-MN) and total nitrates in plasma increased in proportion to the administered dose. This indicates that the fraction of the dose absorbed was the same for all the formulations but that the extent of first-pass metabolism increased in the order sublingual spray < sublingual tablet < peroral tablet. Thus, compared to the spray, the relative bioavailability of ISDN was 48% and 28% from the sublingual and peroral tablets, respectively.The haemodynamic effects were quantified using the a/b ratio of the finger pulse wave and the systolic blood pressure and heart rate under orthostatic conditions. For the a/b ratio of the finger pulse, the maximal effect was higher (e_max=130%) and the time to e_max (t_emax) shorter (16.6 min) after the spray than the sublingual tablet (84.4% and 25.5 min) or peroral tablet (90.2 and 31.3 min). The onset of effect was within 3, 5 and 7.5 min after the spray, sublingual and peroral tablets, respectively. A larger change in the orthostatically-induced decrease in systolic blood pressure and increase in heart rate was obtained following peroral than sublingual administration despite the similar plasma concentrations of ISDN. This probably reflects the larger amount of pharmacodynamically active mononitrate metabolites formed after oral dosing. The integrated effect following administration of 2.5 mg ISDN as spray was similar to that of a sublingual tablet of 5 mg.     

Low doses of the 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH DPAT) increase ethanol intake

Previous work has reported that the 5-hydroxytryptamine (5-HT)_1A agonist, 8-hydroxy 2-(di-n-propylamino)tetralin (8-OH DPAT), reduces ethanol intake by rats. However, as 8-OH DPAT reduces 5-HT neurotransmission, these findings are inconsistent with the proposed inhibitory role of central 5-HT neurons on ethanol intake. We examined the effect of 8-OH DPAT on ethanol, water and food intake in rats maintained on a limited access schedule using a lower dose range (6–250 µg/kg) and by assessing concomitant changes in behaviour. Low doses of 8-OH DPAT enhanced ethanol intake even when food and water were offered as alternatives. Suppression in ethanol intake was observed at higher doses where elements of the 5-HT syndrome were apparent. Similar observations were made in both fluid and non-fluid deprived water drinking rats, suggesting the latter effect is non-selective. Therefore 8-OH DPAT may both increase or decrease ethanol consumption in the rat depending on the dose used.     

Phase I/II trial of dipyridamole, 5-fluorouracil,leukovorin, and mitoxantrone in metastatic breast cancer

Summary Based upon the hypothesis that dipyridamole would potentiate the cytotoxicity of mitoxantrone and the combination of 5-fluorouracil (5-FU) and leukovorin, we performed a phase I/II trial of the combination of dipyridamole, 5-FU, leukovorin, and mitoxantrone in patients with metastatic breast cancer. The dose of dipyridamole was fixed at 175 mg/m² by mouth every 6 h (700 mg/m²/day), based upon a previous phase I trial of oral dipyridamole with 5-FU and leukovorin. Dipyridamole therapy began 24 h prior to the first dose of chemotherapy and continued until 24 h after the last dose of chemotherapy for each course of treatment. At the initial dose level, leukovorin 200 mg/m² was given intravenously immediately prior to 5-FU 375 mg/ m² intravenously on days 1–5. Mitoxantrone 6 mg/m² was given as a single dose on day 3. Unacceptable toxicity was observed at this dose level, leading to successive dose decrements rather than dose increments. The maximum tolerated dose was leukovorin 200 mg/m² days 1–2, 5-FU 375 mg/m² days 1–2, mitoxantrone 6 mg/m² on day 2, and dipyridamole 175 mg/m² every 6 h on days 0–3. Two responses were produced in 15 patients. This regimen is not recommended for further investigation in the treatment of breast cancer.     

Effect of pindolol on endocrine and temperature responses to buspirone in healthy volunteers

Ten healthy subjects received buspirone (30 mg orally) with and without pre-treatment with the 5-HT1A receptor antagonist, pindolol (80 mg over 3 days). Following pindolol treatment the growth hormone and hypothermic responses to buspirone were significantly decreased. There was also a delay in the onset of the prolactin response to buspirone but the total amount of prolactin secretion, calculated as area under the curve, was not significantly reduced. The data suggest that the growth hormone and hypothermic responses to buspirone in humans are mediated by 5-HT1A receptors, but an explanation founded on pharmacokinetic factors cannot presently be excluded. Both this latter possibility and the lack of selectivity of pindolol for 5-HT receptors indicate the need for the further neuroendocrine studies of the mode of action of buspirone, preferably with more selective 5-HT1A receptor antagonists.     

Analysis of the epsilon-sarcoglycan gene in familial and sporadic myoclonus-dystonia: evidence for genetic heterogeneity.

The epsilon-sarcoglycan gene (SGCE) on human chromosome 7q21 has been reported to be a major locus for inherited myoclonus-dystonia. Linkage to the SGCE locus has been detected in the majority of families tested, and mutations in the coding region have been found recently in families with autosomal dominant myoclonus-dystonia. To evaluate the relevance of SGCE in myoclonus-dystonia, we sequenced the entire coding region of the epsilon-sarcoglycan gene in 16 patients with either sporadic or familial myoclonus-dystonia. No mutations were found. This study suggests that epsilon-sarcoglycan does not play an important role in sporadic myoclonus-dystonia and supports genetic heterogeneity in familial cases.     

5-Methoxytryptophol and melatonin in children: Differences due to age and sex

Abstract: It seems clear that the pineal hormone, melatonin (N-acetyl-5-methoxytryptamine), is involved in the reproductive behavior of several animal species including humans. Moreover, several data also support a role for 5-methoxytryptophol (ML), another pineal hormone, in the control of sexual processes. To test the role of ML in human reproductive axis, 128 healthy children, 68 boys and 60 girls, were studied. Each of these groups was divided in three age subgroups of 6, 11, and 14 years. A single blood sample (0900 hours) was obtained from each subject to determine melatonin, ML, FSH, LH, estradiol (girls), and testoterone (boys) by RIA. Statistical analysis of the data included ANOVA-II (factor I: age, factor II: sex) and an analysis of covariance with age as covariate. A similar plasma melatonin concentration, with a significant decrease between 6 and 11 years, was found in boys and girls. Melatonin concentrations correlate well with initiation of the pubertal development in these children, although no sex differences were found. Concentrations of ML are approximately 50% of those of melatonin. In contrast to melatonin, ML levels show significant age and sex differences. Plasma ML concentration significantly increased in boys ( P < 0.001) and decreased in girls (P < 0.001) after 8 years of age. These results support the hypothesis that, besides melatonin, other pineal compounds such as ML may be involved in the maturation process in humans. The pineal indole ML may also be used as a marker of the different chronobiology in the pubertal development in boys and girls.     

Effect of psychotomimetics and some putative anxiolytics on stress-induced hyperthermia

Summary Stress-induced hyperthermia (SIH), which is seen in the last mice removed from the cage, is a novel animal model sensitive to anxiolytic drugs. SIH is antagonized by CL 218872 (25 and 50 mg/kg, os), by tracazolate (5 and 7.5 mg/kg, ip) and by 2-AP-5 (50 and 100 mg/kg, ip). At higher dose, CL 218872 (100 mg/kg, os) and tracazolate (12.5 mg/kg, ip) lose their activity.PK 9084 (5–40 mg/kg, ip) and CGS 9896 (2–20 mg/kg, both ip and os) were also ineffective in preventing SIH. The anti-hyperthermic effect of CL 218872 (25 mg/kg) and tracazolate (7.5 mg/kg) was blocked by the benzodiazepine antagonist Ro 15–1788 (15 mg/kg). CGS 9896 (10 mg/kg, os) also reversed the effect of CL 218872 (25 mg/kg) on SIH.Differently from anxiolytics, MK-801 (0.5–1 mg/kg, os), PCP (2.5 mg/kg, ip) and d-amphetamine (10 mg/kg, ip) evoked hyperthermia in the first set of mice and prevented a further stress-induced rise of body temperature in the last set of mice.     

Expressed emotion in children: associations with sibling relationships

Objective   To investigate the reliability and validity of the expressed emotion (EE) measure, the Pre-school Five Minute Speech Sample (PFMSS), in child-to-child sibling relationships.
Method   A total of 106 boys aged 7–11 were recruited from 12 mainstream primary schools in North Wales. The children completed the PFMSS regarding their sibling and two self-report measures of sibling relationship: the Sibling Relationship Questionnaire (SRQ) and a Child Visual Analogue Scale (CVAS). The parents of 60 participants completed the Strengths and Difficulties Questionnaire regarding the behavioural problems of the participating child and his younger sibling.
Results   The PFMSS demonstrated good inter-rater and code–recode reliability. The significant associations between EE dimensions such as relationship, positive comments and critical comments with various components of the SRQ and CVAS provided support for the concurrent validity of the PFMSS. Significantly higher levels of Conflict and Rivalry and significantly lower levels of Warmth/Closeness on the SRQ were reported by children with high EE, demonstrating good discriminant validity for the PFMSS. There was no significant association between the child's EE profile and the behavioural difficulties of both siblings as reported by parents.
Conclusions   The study found that the PFMSS is a valid and reliable measure of child EE. Future research is needed to clarify the concurrent validity of the warmth and initial statement components of the measure as well as the association between EE dimensions and behaviour.     

5-Br-PADAP催化光度法测定锰的研究

实验中发现Mn（Ⅱ）能够催化5-Br-PADAP与过氧化氢之间的氧化还原反应，并找到了Mn^2＋浓度与催化褪色反应速度间的线性关系，线性浓度范围为0．5-10ng／mL，最小检出浓度为0．2ng／mL。方法灵敏度高，选择性好。     

Insulin resistance Type A and short 5th metacarpals.

BACKGROUND/AIMS: Insulin resistance is associated with a number genetic syndromes and a variety of defects of insulin action. METHODS: We describe three members of an extended family spanning two generations with insulin resistance Type A and short 5th metacarpals. The proband had secondary amenorrhoea, male pattern hair distribution, acne, hirsutism, deep voice, acanthosis nigricans, polycystic ovaries, diabetes, features of acromegaly, raised creatine kinase and triglyceride levels and short 5th metacarpals. Her growth hormone, adrenal steroid and testosterone levels were normal. The proband's daughter had severe acne, hirsutism, acanthosis nigricans, polycystic ovaries, raised triglyceride, glucose and testosterone level short metacarpals and normal insulin receptor gene. The proband's son had a muscular build, raised creatine kinase, hypertriglyceridaemia and short 5th metacarpals. His fasting insulin levels were normal but pro-insulin was raised. RESULT/CONCLUSION: There are many familial and genetic syndromes associated with insulin resistance. This family was diagnosed as having insulin resistance Type A. This family does not conform entirely to any of the previously described syndromes and a number of family members have the phenotype of short 5th metacarpals, which appears to be associated with the features of insulin resistance Type A.