Biochemical Changes after Vertical Banded Gastroplasty for Morbid Obesity

A prospective study of biochemical changes after vertical banded gastroplasty for morbid obesity, in 94 patients (10 males and 84 females, ages ranging from 18 to 59 years) has been carried out. Liver function tests and electrolyte estimations were performed preoperatively, during hospitalisation for surgery, at 6 weeks and at 6 months postoperatively, and demonstrated no significant changes in liver function in these patients 6 months after surgery. The study concludes that there is no increase in the risk of liver damage or electrolyte disturbance after vertical gastroplasty, but that there may be subtle hepatic changes present as gall bladder disease developed in 18 patients postoperation (19%).     

The representation of pleasant touch in the brain and its relationship with taste and olfactory areas

Although there has been much investigation of brain pathways involved in pain, little is known about the brain mechanisms involved in processing somatosensory stimuli which feel pleasant. Employing fMRI it was shown that pleasant touch to the hand with velvet produced stronger activation of the orbitofrontal cortex than affectively neutral touch of the hand with wood. In contrast, the affectively neutral but more intense touch produced more activation of the primary somatosensory cortex than the pleasant stimulus. This indicates that part of the orbitofrontal cortex is concerned with representing the positively affective aspects of somatosensory stimuli, and in further experiments it was shown that this orbitofrontal area is different from that activated by taste and smell. The finding that three different primary or unlearned types of reinforcer (touch, taste, and smell) are represented in the orbitofrontal cortex helps to provide a firm foundation for understanding the neural basis of emotions, which can be understood in terms of states elicited by stimuli which are rewarding or punishing.     

Clozapine as a drug of dependence

Rationale: In schizophrenics, clozapine has been reported to induce various withdrawal signs and rapid onset relapse to psychosis on cessation of chronic treatment. Objective: The study was designed to develop an animal model of one aspect of clozapine tolerance and withdrawal using core body temperature measures. Methods: Two groups of 15 female Wistar rats were treated chronically (b.i.d.) with clozapine at 6 or 12 mg/kg per injection for 21 days prior to cessation of drug treatment, withdrawal being studied over 4 consecutive days. Body temperatures were assessed daily throughout the study. Results: Acutely, clozapine induced dose-related hypothermia, to which complete tolerance developed in both groups, the development of tolerance being more rapid in the group treated with 6 mg/kg per injection of clozapine. During withdrawal only the group treated chronically with 12 mg/kg per injection of clozapine showed rapid onset significant hyperthermia. This dissipated progressively over days, and was completely absent after 4 days of withdrawal. Conclusions: Clozapine induced a clear somatic withdrawal sign after chronic treatment. It is suggested that, in future research in both humans and animals, it is important to attempt to differentiate between clozapine withdrawal and clozapine withdrawal-induced relapse to psychosis. It is also important to characterise the clozapine withdrawal syndrome fully in animals; to establish the neurochemical mechanisms involved in such withdrawal; and to determine which novel antipsychotics are most efficacious in inducing clozapine-like withdrawal effects, in suppressing clozapine withdrawal, and in preventing relapse to psychosis in patients being transferred from clozapine to novel atypical antipsychotic drugs. Received: 14 May 1998/Final version: 14 September 1998     

Acute and nongenomic effects of testosterone on isolated and perfused rat heart

Gonadal steroid hormones influence vascular tone and the development of hypertension. There are sex differences in the incidence of cardiovascular diseases, and great attention has been placed on the study of estrogen cardiovascular effects. However, there are only a few reports on the effects of testosterone on the vasculature. It is commonly accepted that the mechanism of the action of steroid hormones on target tissues is mediated through the binding of hormones to cytoplasmic or nuclear receptors. However, some studies indicate that steroid action can be extremely rapid and therefore unlikely to be through a genomic mechanism. The purpose of this study was to assess the effect of intravascularly confined testosterone on an isolated rat heart to demonstrate acute and possibly nongenomic effects of the steroid. Our results show that testosterone blocked the adenosine vasodilator effect and increased vascular resistance, even when its presence was restricted to the coronary vascular lumen. These effects were exerted rapidly and possibly through nongenomic mechanisms.     

Patients' and doctors' perception of long-term morbidity in patients with testicular cancer clinical stage I

Patient-based questionnaires were designed with the aim to identify and rank long-term somatic and psychosocial morbidity in patients with low-stage testicular cancer. A further intention was to compare patients' assessments with experienced doctors' general opinion on quality of life items in cured testicular cancer patients. In pilot study I, 103 tumour-free patients ranked items of physical and psychosocial morbidity after having had various kinds of treatment. Though the ranking procedure appeared to cause some difficulties amongst the patients and subsequently was abandoned, the results indicated considerable differences between the patients' and doctors' evaluations. In pilot study II patients were asked to score the different items. The questionnaire of pilot study II was completed by 107 patients from the Norwegian Radium Hospital (NRH) and 99 relapse-free patients from the Royal Marsden Hospital (RMH) with testicular cancer stage I at least 1 year after infradiaphragmatic radiotherapy (n = 94) or adjuvant chemotherapy (2 cycles,n=26), or patients who had been followed on the surveillance program (n = 86). A total of 93 doctors completed a similar questionnaire, thereby expressing their general opinion on long-term morbidity in comparable testicular cancer patients as seen during routine clinical follow-up. Both the irradiated patients and those on the surveillance program reported slight degrees of Raynaud-like phenomena, neurotoxicity and ototoxicity, most probably representing background morbidity in an age-matched general male population. Doctors tended to underestimate their patients' somatic morbidity, but often overestimated the degree of psychological distress, in particular in patients on the surveillance program. Significant differences between RMH and NRH patients with regard to sexual problems and to leisure time activity may be explained by cultural differences in the two countries. The items presented in the questionnaire used identify important issues for patients cured of testicular cancer which may be used in future multicentre trans-cultural studies assessing these patients' quality of life. This will provide sufficient data for psychometric testing and, together with the findings from patients' free comments, support the final design of a testicular cancer quality of life module.     

The effect of organizational type and hierarchical level on nurses' perceptions of hospital issues

Managers in four acute care hospitals in southeast Florida described the resource, management, outcome, and external issues confronting their organizations. Eight major issues and four contributing and resulting subissues associated with each were identified from the 746 separate issue statements the managers made. Nurses in the same four hospitals were asked to evaluate the impact of the eight issues on their organization and their work, as well as the extent to which the subissues had either contributed to or resulted from the main ones. Overall perceptual patterns are discussed, as well as the differential effects of both hospital type and level of employment on perceptions. It is suggested that differential perceptions among such a key component of the care delivery system as nurses will need to be better understood as hospitals seek to survive in a turbulent environment.     

Genetic manipulation of mammary epithelium by transplantation

Genes can be introduced into mammary epitheliumin vivo by the tissue reconstitution method. Primary cultures of mammary epithelial cells are prepared, a gene introduced using retrovirus vectors, and the cells transplanted into a mammary fat pad from which the normal epithelium has been removed. The cells reform an epithelium in which some cells express the introduced gene. The technique is reviewed and compared with the mammary-specific expression of genes in transgenic mice. To model the development of neoplasia, particularly the preneoplastic changes caused by a single oncogene alone, several oncogenes have been expressed this way—myc, Ha-ras, erbB, erbB2,Wnt-1, andhst/FGF-4. Each caused a different alteration to the growth pattern of the epithelium, such as altered branching, premature alveolus development, distorted duct structure, or altered hormone sensitivity. Insights into normal development have also been obtained by inappropriate expression of genes such asWnt-4.     

The septal arteries in the differential diagnosis of constrictive pericarditis

Angiographic study of the motion of the septal and left marginal arteries was performed in patients with restriction in ventricular diastolic filling in order to separate patients with constrictive pericarditis from those with restrictive cardiomyopathy. Twelve patients with constrictive pericarditis (group I) and 10 patients with restrictive cardiomyopathy (group II) were evaluated and compared with 21 patients with normal coronary angiograms (group III). The displacement of the septal arteries (23 +/- 2.04 mm) was abnormally exaggerated in group I and normal (9 +/- 0.81 mm) in groups II and III. The displacement of the left marginal arteries as seen by the "corrugating index" was similar in all groups. We conclude that study of the displacement of the septal arteries is a useful angiographic sign that helps to separate constrictive pericarditis from restrictive cardiomyopathy and normals.