Is smoking linked to positive symptoms in acutely ill psychiatric patients?

Background: The self-medication hypothesis is commonly put forward to explain the high prevalence of smoking in psychiatric patients. However, studies supporting the self-medication hypothesis have most often been carried out on chronic patients stabilized by antipsychotics.

Aim: Given that antipsychotics tend to erase psychiatric symptoms, the present study was undertaken on acutely ill patients usually receiving no medications, or on whom medications are ineffective.

Electrophysiological characterization of harmane-induced activation of mesolimbic dopamine neurons.

It has been suggested that the beta-carbolines harmane and norharmane may be involved in the pathophysiology of Parkinson's disease, psychosis and addiction, but the mechanisms of these possible effects remain to be elucidated. In the present study, the effects of the two compounds were examined by using in vivo extracellular recordings of ventral tegmental dopamine neurons. The effects of harmane (2mg/kg) and norharmane (2mg/kg), were compared to those of nicotine (11microg/kg), of cotinine (0.

[The European report "Lifting the Smoke-Screen": epidemiological study or manipulation?].

Background: This report ends up with a large increase of the number of estimated deaths from passive smoking in Europe. Its conclusions have been decisive to passing laws banning smoking in public places.

Results: However, analysis of this report for France reveals considerable anomalies, such as changing the usual definition of passive smoking.

Chronic intermittent nicotine treatment dose-dependently alters serotonergic neurons response to citalopram in the rat.

Acetylcholine nicotinic systems and serotonergic systems are known to interact. In rodents, acute and chronic nicotine treatments have consequences on several aspects of the activity of dorsal raphe serotonin (DRN 5-HT) neurons. One hypothesis is that states of functioning of DRN 5-HT neurons (firing rate and sensitivity) vary as a function of nicotine dose and mode of administration during chronic nicotine treatment.

Comparison of self-reports and biological measures for alcohol, tobacco, and illicit drugs consumption in psychiatric inpatients.

Background: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures.

Effects of tobacco and cigarette smoke extracts on serotonergic raphe neurons in the rat.

Tobacco components other than nicotine might participate in the behavioural effects of smoking. In this study, in-vivo recordings of serotonergic dorsal raphe neurons were performed in the anesthetized rat, whereas tobacco extracts, cigarette smoke extracts, nicotine, nornicotine or anabasine were intravenously injected. All substances inhibited the neurons, and all inhibitions were completely blocked by the nicotine receptor antagonist mecamylamine.

Harmane inhibits serotonergic dorsal raphe neurons in the rat.

Rationale: Harmane and norharmane (two beta-carbolines) are tobacco components or products. The effects of harmane and norharmane on serotonergic raphe neurons remain unknown. Harmane and norharmane are inhibitors of the monoamine oxidases A (MAO-A) and B (MAO-B), respectively.

Nicotine improves memory in an object recognition task in rats.

Nicotine was investigated for its mnemonic effect in a two trials object recognition task. In the first trial, two copies of the same object were presented. In the second trial (24 h after), one of the familiar object and a new object were presented.

[Predictive factors of smoking cessation after myocardial infarction. Review of the literature].

This paper reviews the current state of knowledge about smoking after myocardial infarction in smokers. After presenting results emphasizing the value of post-infarction smoking cessation, all of the predisposing factors to smoking cessation are analysed. The objective of this review of the literature is to recognize these factors in order to more precisely define the various medical, psychological and social aspects of an assistance programme adapted to post-infarction smoking cessation.

Smoking cessation methods: recommendations for health professionals. Advisory Group of the European School of Oncology.

Smoking is the leading preventable cause of death. Approximately 40% of Europeans now smoke. Many smokers want to stop but do not make the attempt, and of those who try, most are unsuccessful.

Failure of behavioral dependence induction and oral nicotine bioavailability in rats.

As failure to induce behavioral dependence to oral nicotine (0.31 mM) might be caused by taste aversion. Sixteen rats were presented nicotine around the taste aversion threshold (0.

[Role of nicotine in the induction and maintenance of tobacco dependence].

Tobacco dependence prevents any reduction in morbidity and mortality related to smoking. Nicotine is widely regarded as responsible for this dependence process. It stimulates ubiquitous cholinergic receptors thus resulting mainly in catecholamine release.

[Digestive absorption of calcium phosphates in man].

Closely similar to the mineral composition of bone, di- and tricalcium phosphates would seem of interest as oral calcium supplement; unfortunately, they are commonly regarded as non-absorbable because of their insolubility. Seven elderly patients received a constant regimen of 1500 mg of calcium a day, supplied either by diet alone, or by a hypocalcemic diet (Ca = 500 mg) supplemented with di- or tricalcium phosphate (Ca = 1000 mg). Calcium balance remained positive under the calcium phosphate treatment.

[Changes of plasma amino acids in cirrhotics treated with ornithine salts].

The plasma amino acid pattern of cirrhotic patients was determined before and after 24 h of continuous infusions of glucose, ornithine alpha-ketoglutarate (O alpha KG), ornithine chlorhydrate (ORN HCl) and sodium ketoglutarate (alpha CGNa). Before treatment, leucine, isoleucine, valine and glutamine levels were low. Tyrosine and methionine levels were high.

A device for jointless connections with unrestrained animals.

An apparatus is described allowing multichannel connection with unrestrained animals without using joints. The twisting of the connection lines caused by the rotation of the animal in its cage is detected by means of a torsion wire connected to an electronic device. This provokes a temporized rotation of the bottom of the cage in the opposite direction in order to untwist the lines.

Effect of liver denervation on the feeding pattern of rats.

This study was undertaken to assess the role of the hepatic innervation in the short-term regulatory mechanisms of food intake. A liver denervation was performed in male Wistar rats: the liver was entirely freed from the surrounding organs, its vessels (with the exception of the hepatic veins) and the bile ducts were stripped. Controls consisted of two groups of liver-denervated rats in which sympathectomy or vagotomy were carried out.

Impairment of memorization by high doses of pyridoxine in man.

Two controlled trials were performed successively to evaluate the effect of high doses of oral pyridoxine on brain performance in man. In trial I, medical students volunteered to take 100 mg, 500 mg of pyridoxine a day or placebo for 10 days. A digit coding test was performed before, and at the end of the treatment period and a third 15 days later.