In order to verify the presence of Low Density Lipoprotein Receptor (LDLR) in cellular membranes isolated from human colonic tissue, samples from the neoplastic colorectum and the normal surrounding mucosa were studied by an enzyme-linked-immunosorbent assay. A monoclonal antibody against the human LDLR was used. The LDLR content revealed a considerable inter-individual variation. In 36 out of 53 cases (68%) there was no LDLR presence in either normal or neoplastic tissue samples. In 5 out of 53 cases (9.4%), LDLRs were detected in both types of tissue samples, in 9 cases out of 53 (17%) LDLRs were present in neoplastic tissue, while in 3 out of 53 cases (5.6%) only in normal mucosa. The anti-LDLR mono-clonal antibody (mAb) binding was significantly higher in neoplastic tissue samples than normal surrounding colonic mucosa ones. Sex, age, body mass index (BMI), serum cholesterol, tumour site, histologic grading and Dukes' stage did not seem to be associated with LDLR presence.

Adenocarcinoma↗

PubMedDate not supplied

Lisuride and bromocryptine in L-Dopa stable-responder parkinsonian patients: a comparative, double-blind evaluation of cardiopressor and neurochemical effects.

In this study, we compared the haemodynamic and biochemical effects of bromocryptine to those of lisuride, in L-Dopa stable responder parkinsonian (PD) patients. Nineteen PD patients were admitted to the study. A double-blind, parallel group, randomized study was performed. Patients were randomly chosen to receive lisuride or bromoryptine. Both drugs were administered in increasing dosages until a maximum of either 0.6 mg lisuride or 7.5 mg bromocryptine was reached. The following tests were carried out: periprandial study, tilt table test and cardiovascular tests (sustained handgrip test, deep-breathing, lying-to-standing and Valsalva manoeuvre). During the tests, systolic and diastolic blood pressure and heart rate were monitored with an automatic sphyngomanometer. Blood samples for catecholamine assay were taken during tilt table test. In basal conditions 70% of the randomly chosen men in the bromocryptine group showed significant orthostatic hypotension (OH), while only one subject in the lisuride group demonstrated comparable OH values. The deepest derangement of orthostatic regulation was observed in the lisuride group but it should not be attributed to the greater hypotensive effects of this drug. Infact, the cardiopressor effects of bromocryptine may well be "masked" by the alteration detected in baseline conditions. Only bromocryptine significantly reduced supine and orthostatic NE plasma levels on the 14th day of therapy. Neither bromocryptine nor lisuride significantly altered periprandial blood pressure values. In conclusion, this study demonstrates that lisuride and bromocryptine are well tolerated as far as the analysis of the development of hypotensive effects is concerned. Further, more sophisticated study, with other agents that block the peripheral and/or central effects of dopamine-agonists in PD patients should be conducted in order better to define the precise role of these types of agents and the potential cardiopressor risks in these subjects.

Aged↗

PubMedDate not supplied

Polyamine oxidase activity and polyamine levels in human colorectal cancer and in normal surrounding mucosa.

BACKGROUND: Polyamine oxidase (PAO) is an enzyme involved in the interconversion pathway of polyamines, compounds required for cell proliferation and differentiation. As the role of PAO in tumor growth is unclear, and no data about PAO activity in human colorectal carcinoma are available, our aim was to investigate PAO activity and polyamine levels in this kind of tumor. METHODS: Polyamine levels and PAO activity were detected in 30 neoplastic colorectal samples and surrounding mucosa by HPLC. RESULTS: Free and N1-acetylated polyamine levels were higher in the neoplastic tissue than surrounding mucosa of the same patient. On the contrary, PAO activity was significantly lower in the neoplastic tissue than surrounding mucosa. CONCLUSION: It seems that PAO activity does not play an important role in the increased free polyamine levels in human colorectal carcinoma. Instead, the low PAO activity observed in our study let us to hypothesize that polyamine analogues can have an antitumoral effect on colorectal carcinoma.

Adult↗

PubMedDate not supplied

Carotid artery atherosclerosis and risk factors for stroke in a selected population of asymptomatic men.

The prevalence of carotid atherosclerosis in the general population is variable. Also, the relationship between cardiovascular risk factors and carotid atherosclerosis has yet to be clearly defined. We carried out a cross-sectional study of 441 asymptomatic male subjects to investigate possible relationships between extracranial carotid plaques, cardiovascular risk factors and asymptomatic coronary obstructive disease. Carotid atheromatous plaques, detected by means of B-mode ultrasonography, were present in 31.7% of the study population. Prevalence and severity of atherosclerosis were significantly correlated with age, total cholesterol and signs of ischemia upon exercise stress test. However, hypercholesterolemia seemed to play a significant pathogenic role only in the youngest subjects (<55 years old). Our study confirms the high prevalence of asymptomatic carotid plaques in the general population, especially in elderly subjects. The only reversible risk factor related to carotid atherosclerosis is hypercholesterolemia, and this is reversible only at a young age.

Age Factors↗

PubMedDate not supplied

Cluster headache and periodic affective illness: common chronobiological features.

Many of the seasonal changes occurring in animals appear to be associated with photoperiodic modifications, and particularly with the duration of the phases of exposure to light and dark. The integration of these processes is made possible by the normal functioning of biological oscillators or synchronizers, presumably located at the hypothalamic level. Cluster headache (CH), seasonal affective disorder (SAD) and bipolar mood disorders are conditions bearing numerous analogies, particularly as regards the temporal pattern of disturbances, the nature of predisposing or precipitating factors, the peculiar relationship with sleep, the neuroendocrine findings, and the clinical response to current treatments. The secretion of melatonin, which is influenced by the light/dark cycle, displays a bimodal pattern, which is likely to be dictated by the activity of distinct synchronizers for light and dark. Changes in the secretory pattern of this neurohormone have also been documented in both CH and SAD. The possibility of normalizing the secretory rhythm of melatonin by means of phototherapy in SAD, and the therapeutic use of the hormone to prevent the recurrence of active phases in CH, represent further interesting similarities between these two disorders. Melatonin, acting as a unique neuroendocrine transductor of photic inputs, may therefore be viewed as a marker of dyschronic disease to be used in patients suffering from CH and affective illness, for both diagnostic purposes and to assess the response to pharmacological and non pharmacological treatments.

Antidepressive Agents↗