A comparison of some physiological and psychological effects of propranolol and diazepam in normal subjects

1 Some central and peripheral effects of orally administered propranolol (60 mg), diazepam (5 mg) and placebo were compared in normal subjects.

2 The central effects measured were changes in magnitude of the contingent negative variation (CNV) and subjective anxiety ratings; the peripheral effects were changes in heart rate, blood pressure, galvanic skin response and hand steadiness.

3 After diazepam there was a decrease in CNV magnitude and in the level of subjective anxiety; there was a slight fall in blood pressure but little change in heart rate.

4 After propranolol, on the other hand, there was no significant change in CNV magnitude or anxiety rating, but a significant fall in heart rate and systolic blood pressure.

5 It is concluded that, at the dosage used, propranolol, unlike diazepam, does not affect the central mechanisms determining CNV magnitude or subjective anxiety. The relationship of this finding to the use of β-adrenergic receptor blockers in clinical anxiety states is discussed.

     

Knowledge and attitudes about otitis media risk: implications for prevention

OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for 相似文献   

Long-chain polyunsaturated fatty acid transport across the perfused human placenta

The role of the placenta in controlling the supply of fatty acids to the fetus was investigated in term placentae (n=9) from normal pregnancies. The maternal side was perfused ex vivo for 90 min with a modified Krebs Ringer solution containing a physiological mixture of fatty acids and ratio of fatty acid to human albumin. There was no evidence of chain elongation and desaturation of the essential fatty acids. Relative to the value for oleic acid, the rate of transfer to the fetal circulation was: 1.30±0.02 (P<0.001) for linoleic acid, 1.61 ± 0.09 (P=0.002) for α-linolenic acid, 0.67 ± 0.10 (P=0.033) for arachidonic acid and 2.I0 ± 0.16 (P=0.003) for docosahexaenoic acid. For tissue accumulation the values were 1.47 ± 0.39 (P<0.001) for linoleic acid, 2.24 ± 0.37 (P=0.027) for α-linolenic acid, 9.84 ± 1.03 (P=0.001) for arachidonic acid, and 3.01 ± 0.79 (P=0.064) for docosahexaenoic acid. The order of selectivity for transfer from the maternal to the fetal circulation was docosahexaenoic>α-linolenic>linoleic>oleic>arachidonic acid. Such a mechanism would allow the preferential transfer of docosahexaenoic acid and the essential fatty acids to the fetal circulation, thereby protecting the polyunsaturated fatty acid supply to the fetus during a critical period of development.     

Free and esterified fatty acid and cholesterol synthesis in adult males and its effect on the doubly-labelled water method

The purpose of the present study was to estimate whole-body fatty acid and cholesterol synthesis in weight-stable adults and to determine the likely effect on the doubly-labelled water (DLW) method for measuring energy expenditure. Synthesis was measured by 2H incorporation over 14 d in six adult males in approximate energy balance following noradrenaline infusion to maximize mobilization of free fatty acid from adipose tissue. The inter-individual variation in synthesis rates was large and in one subject the proportion of free fatty acid synthesized was ten times that of the mean of the rest of the group; the fasting concentration of esterified fatty acid in this subject was five times that of the rest of the group indicating likely violation of the assumptions underlying the calculation of whole-body synthesis. After 14 d of labelling in the other five subjects, 0.9 (SEM 0.3)% of the circulating free fatty acid, 9.3 (SEM 3.0)% of the esterified fatty acid, 14.6 (SEM 2.4)% of the free cholesterol and 28.3 (SEM 3.7)% of esterified cholesterol had been synthesized de novo. A high rate of synthesis correlated with a low pre-dose 2H abundance both within and between lipid classes suggesting that natural 2H abundance variations in some lipid classes may be used to determine their metabolic origin. Whole-body synthetic rates were 8 g/d for fatty acid and 0.3-0.5 g/d for cholesterol. These values correspond to very small errors on DLW-derived estimates of CO2 production; -2.5 litres/d for fatty acid and -0.1 to -0.2 litres/d for cholesterol. These results, obtained in subjects typically consuming a diet with a lower fat and cholesterol content that the typical Western diet, suggest that the DLW method is unlikely to be affected by fatty acid and cholesterol synthesis in subjects in energy balance consuming a typical Western diet.     

Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon

We have examined whether dietary polyamines influence the formation and initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in rat colon. Effects of a combination of dietary polyamines at three dose levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g; spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied in animals in two different experimental situations: animals treated with AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a specific inhibitor of endogenous polyamine synthesis. In both experimental situations, dietary polyamines enhanced the growth of ACF, expressed as the number of large ACF (foci with three or more aberrant crypts, ACF > or = 3), whereas the formation of ACF, expressed as the number of ACF, was apparently not altered. In animals treated with AOM alone, maximal growth enhancing effect on ACF was nearly obtained with the median level of dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of DFMO was counteracted by dietary polyamines in a dose- dependent manner, and it was abolished at the highest level of polyamines. In conclusion, it was demonstrated that dietary polyamines are able to enhance the growth of AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused inhibition of ACF growth, probably by compensating for the DFMO-reduced endogenous polyamine synthesis.      

二甲双胍治疗抗精神病药物引起的血脂异常:两项随机、安慰剂的对照研究

目的：验证二甲双胍治疗抗精神病药引起的血脂异常的疗效和安全性。方法：将两项随机、安慰剂的 对照研究纳入分析。共有201例服用抗精神病药物后出现血脂异常的首发精神分裂症患者,并将其分为1 000 mg/d 二甲双胍组(以下简称为二甲双胍组,n=103)和安慰剂组(n=98),观察24周。在基线、治疗后第12周和第24周进行 临床症状及体重、血糖、血脂等代谢指标的评估。结果：二甲双胍治疗后,二甲双胍组和安慰剂组之间低密度脂 蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)的平均差异从基线时的0.16 mmol/L,降低到第24周结束时的 –0.86 mmol/L,降低了1.02 mmol/L,差异有统计学意义(P<0.01)。而24周结束时,二甲双胍组LDL-C≥3.37 mmol/L的 患者有25.3%,显著低于安慰剂组24周结束时的64.8%(P<0.01)。与安慰剂组相比,二甲双胍组的体重、体重指数、 胰岛素、胰岛素抵抗指数、总胆固醇、三酰甘油和高密度脂蛋白胆固醇也有显著变化,差异均有统计学意义(均 P<0.05)。治疗对体重和胰岛素抵抗的影响出现在第12周,并且在第24周进一步改善,但对改善血脂异常的作用在第 24周结束时才出现。结论：二甲双胍治疗对于改善抗精神病药物引起的血脂异常和胰岛素抵抗是有效的,并且改善 抗精神病药物诱导的胰岛素抵抗出现的时间早于降低血脂异常的时间。     

“Choke” vessels between vascular territories of the abdominal wall: Literature review and rare case of Leriche's syndrome

We undertook a review of the anatomical changes of “choke” vessels between the internal thoracic artery (ITA) and deep inferior epigastric artery (DIEA), as highlighted by a case of aortoiliac occlusive disease (Leriche's syndrome), and discuss the physiological concepts observed with regard to surgical delay procedures within the abdominal wall performed prior to abdominal cutaneous free flaps and coronary artery bypass grafting. Computed tomographic angiography (CTA) was undertaken on a patient with a rare case of Leriche's syndrome and a literature review of over 200 references on the anatomy, physiology and clinical uses of choke vessels in the abdominal wall was undertaken. The CTA demonstrated that in patients with Leriche's syndrome, there is a marked dilatation of all ITA‐DIEA pathways and increased flow through choke vessels. If these changes can be surgically replicated in the form of a delay procedure for patients seeking to undergo autologous breast construction, this could improve the outcomes of abdominal cutaneous free flaps and coronary artery bypass grafting. We accordingly propose three surgical methods for augmenting blood flow to the abdominal wall: a) ligation of the DIEA; b) ligation of the distal ITA; and c) creation of an arterio‐venous fistulae in the DIEA. Our review of the literature confirmed the viability of these propositions. The dilatation of choke vessels in response to increased haemodynamic stress may thus be utilised to enhance blood supply to tissues prior to transfer and can be achieved through simple and minimally invasive methods. Clin. Anat. 25:998–1004, 2012. © 2012 Wiley Periodicals, Inc.