Brainstem mediates diazepam enhancement of palatability and feeding: microinjections into fourth ventricle versus lateral ventricle

The hypothesis that benzodiazepine-induced hyperphagia is due to a specific enhancement of the palatability of foods has been supported by previous ‘taste reactivity’ studies of affective (hedonic and aversive) reactions to taste palatability. Diazepam and chlordiazepoxide enhance hedonic reactions of rats (rhythmic tongue protrusions, etc.) to sweet tastes in a receptor-specific fashion. A role for brainstem circuits has been indicated by a previous demonstration of the persistence of the taste reactivity enhancement by diazepam after midbrain decerebration. The present study examined whether benzodiazepine brainstem receptors are the chief substrates for palatability enhancement even in intact brains. We compared the effectiveness of benzodiazepine microinjections to elicit feeding and enhance hedonic reactions when delivered into either the lateral ventricle (forebrain) or the fourth ventricle (brainstem) of rats. The results show diazepam is reliably more effective at eliciting feeding and enhancing positive hedonic reactions to oral sucrose when microinjections are made in the fourth ventricle than in the lateral ventricle. We conclude that brainstem neural systems containing benzodiazepine-GABA receptors are likely to be the chief substrates for benzodiazepine-induced palatability enhancement.     

影响脐血IgE值因素的研究

目的　本研究对影响脐血IgE值的可疑因素进行分析 ,探讨影响儿童食物过敏的可疑因素。方法　选取孕期妇女 10 5名及其所生婴儿 ,采用标准问卷调查获取资料 ,对影响脐血IgE的因素进行分析。 结果　母亲的过敏性疾病史、父亲过敏性疾病史中的皮炎表现型、孕期妇女过敏性疾病发作史、有过敏史妇女孕后期摄入过量的牛奶和鸡蛋均与脐血IgE值的上升有关 ,且上述 5个因素对脐血IgE水平的影响依次降低。 结论　母亲的过敏性疾病史和父亲过敏性疾病史中的皮炎表现型是导致新生儿脐血IgE值升高的主要危险因素 ;同时 ,妊娠期加强对有过敏史妇女的保护 ,防止过敏性疾病的复发 ,在孕后期控制有过敏史妇女牛奶、鸡蛋等大分子食物致敏原的摄入 ,有助于降低脐血IgE值。     

Sleeping more as a way to lose weight

Caloric consumption in a society with readily available food is likely to be approximately proportional to the number of hours of being awake. Thus, replacing 1 h of inactive wakefulness (e.g. watching TV), with sleeping is likely to result in a substantial reduction in caloric intake. Calculations are presented to illustrate the possible benefits of such a switch on weight reduction.     

安顺市区沙门氏菌环境污染调查

在贵州省安顺市１９８５年水型伤寒爆发流行后，为调查该市环境中沙门氏菌污染情况，我站于１９８６～１９８８年对市区所属医院和贯城河污水及部分食物的沙门氏菌进行了监测，共采集污水及食品６１９份，沙门氏菌阳性率为４１．８４％，分属Ａ、Ｂ、Ｃ、Ｄ、Ｅ１五个群１２个血清型，伤寒沙门氏菌经Ｖｉ噬菌体分型为Ｍ１型。纸片药敏试验为多重性耐药菌株。阐明了沙门氏菌流行的部分传播媒介途径。     

Effect of dietary fat content on the bioavailability of a sustained release quinidine gluconate tablet

Quinidine gluconate 324 mg sustained release tablets (Quinaglute) was administered as a single dose to 15 healthy male subjects following an overnight fast, immediately following a high fat (HF) breakfast or immediately following a low fat (LF) breakfast. Serum samples were obtained over a 48 h period and analyzed for quinidine content using a high performance liquid chromatographic assay. Under the conditions of the study, both the rate and extent of quinidine bioavailability was significantly affected by food. The extent of bioavailability was statistically significantly greater (p less than 0.05) following both the HF and LF meals as compared to that in the fasted state. Rate of bioavailability was significantly enhanced following the LF meal as compared to that of the other two treatment groups. Although peak concentrations were greater and time to peak concentrations somewhat later following the HF meal versus those under fasting conditions, these differences were not statistically significant. In addition, the characteristics of the serum concentration-time profile (as defined by the number, magnitude, and time of occurrence of the multiple absorption maxima) was unique for each of the three treatment groups. Possible mechanisms underlying these results are explored.     

大渔岛居民膳食结构及营养状况的调查与分析

对山东省荣成市石岛镇大渔岛村９１户３９８名散居渔民膳食结构及营养状况调查的结果表明：①蛋白质和热能人均摄入量占平均供给量的１１５．４％和１１２．２％，其它营养素除维生素Ｂ２占８３．３％以外均摄入较充足。蛋白质、脂肪、碳水化合物的热量构成比分别为１１．３％、２７．６％、６１．１％。②查体中未发现严重的营养缺乏症。③体重指数超过正常者占１３．２％。④体重指数与收缩压、舒张压经相关回归分析，呈显著相关。⑤大渔岛居民头发锌含量高于泰安农民，铜、铁含量低于泰安农民。     

Effects of food deprivation on cocaine base smoking in rhesus monkeys

Studies have shown that both food deprivation and response cost have important influences on the magnitude of self-administration of a wide variety of psychoactive drugs. In an attempt to extend these findings to the smoked route of drug self-administration, the effects of food allotment and fixed-ratio (FR) value were evaluated in four male rhesus monkeys trained to smoke cocaine base. In the first phase of the experiment, monkeys were trained to self-administer smoked cocaine base under a chained progressive-ratio (PR), fixed-ratio (FR) schedule during daily experimental sessions. Monkeys were required to make 20 lever-press responses and then five inhalations on a smoking spout to obtain the first smoke delivery. The lever ratio then increased to 60, 140, 300, 620, 1260, 2540, and 4940 for each successive smoke delivery. The initial lever ratio value was reset to 20 at the beginning of each daily session. The body weights of three monkeys were determined under free-feeding conditions. Monkeys were then restricted to 100 g food and, when body weights had stabilized, the daily food allotment was increased to 150 g, approximately 210 g, or greater than 400 g (satiation). As the daily food allotment and body weight increased, the mean number of smoke deliveries decreased in two of three monkeys. In the second phase of the experiment, three monkeys were maintained under either food-satiated or food-restricted conditions. Body weights were maintained at approximately 90% of their free-feeding weights under food-restricted conditions. The cost of the drug (lever FR value) was constant within each experimental session, but was increased after 3 consecutive days of stable responding. Fixed-ratio values were increased from 128 to 256, 512, 1024, and 2048. Monkeys were required to complete the lever FR value and then to make five inhalations on the smoking spout to gain access to 1.0 mg/kg per delivery cocaine base. The mean number of smoke deliveries increased at FR 256, 512, and 1024 when monkeys were food-restricted as opposed to food-satiated. Correspondingly, the mean number of responses increased under food-restricted conditions. Responding continued to increase over a wider range of FR values, and the peak number of responses was higher under food-restricted, as opposed to food-satiated conditions. These results, using the smoking route of administration, are consistent with the hypothesis that food deprivation increases the self-administration of reinforcing drugs.     

Intakes and major dietary sources of cholesterol and phytosterols in the British diet

Cholesterol intakes in Britain have been re-estimated by analysing Total Diet samples taken in 1991 and from 1993 National Food Survey records. The Total Diet samples contained only 284 mg/day compared with 319 mg/day in 1987 and 337 mg/day in 1981, while the National Food Survey showed intakes had fallen to 238 mg/day from 259 mg/day in 1990 and 405 mg/day in 1970-75. More details of the intakes by adults in 1986/87 are given, and compared with the results from the other methods. Daily intakes of eight phytosterols were also estimated, the main ones being β-sitosterol, campesterol, stigmasterol and 57-stigmastenol whose intakes were 104, 49, 10 and 4 mg/day, respectively, in 1991. These intakes had increased since 1981, reflecting the rising consumption of vegetable oils.     

Effects of food restriction and refeeding on adipocyte glucose metabolism in Zucker rats

Chronic food restriction has been shown to enhance glucose metabolism in adipocytes from lean Zucker rats at 10, 26, and 52 weeks of age compared to ad libitum-fed lean rats. Only adipocytes from food restricted 10-week-old obese rats demonstrated this response. In this study, lean and obese rats were food restricted from 5 until 14 weeks of age to determine the age at which adipocytes from obese rats were no longer affected by this intervention. Effects of 1 week of refeeding were also determined. When the rats were killed, body weights were highest in control rats followed by restricted/refed and then restricted rats within each genotype. Epididymal pad weights of lean rats were resistant to dietary intervention, while those of obese-restricted and obese-restricted/refed rats weighed less than pads of obese-control rats. Retroperitoneal pad weight was lowered by food restriction in both genotypes; but only that of lean-restricted/refed rats totally recovered with refeeding. Adipocytes of lean-restricted rats had the highest conversion of glucose to CO₂. Glyceride-glycerol production was higher in obese compared to lean rats, but restricted rats had elevated conversion of glucose to fatty acids. In general, these results indicate that by 14 weeks of age obese Zucker rats no longer respond to food restriction with an elevated rate of glucose metabolism in adipocytes.     

嘉定区1988—1993年细菌性食物中毒样品检测分析

本区六年共检测食物中毒样品３２３份，检出致病菌１３８株，检出率为４２．７２％。致病菌菌型以付溶血性弧菌居首（７６．８１％），溶藻弧菌次之（８．７０％），鲍氏１￣６型痢疾菌最低（０．７２％）。六年来致病菌检出无升降趋势（ｒ＝０．０２８，Ｐ〉０．０５）。致病菌检出第三季度较高；男女间致病检出相差显著（χ＾２＝１２．３５，Ｐ〈０．０１）。