[Gorlin-Goltz syndrome]. / Sindrome di Gorlin-Goltz.

The Nevoid Basal Cell Carcinoma Syndrome (NBCCS) or Gorlin-Goltz syndrome, principally characterized by basal cell carcinomas, multiple jaw cysts and skeletal anomalies, is an interesting pathology for the dentist who is often the first clinician involved in the diagnosis of this syndrome. Because of the multisystem involvement and variable expressivity of NBCCS, patients affected by this syndrome must be evaluated by many medical and dental specialists in order to properly sequence their treatment.

NMDA receptors are involved in dithiothreitol-induced hypothermia.

Sulfhydryl-reducing agents, such as dithiothreitol, modulate glutamate N-methyl-D-aspartate (NMDA) receptors. Since these receptors are involved in thermoregulatory processes, we studied the effects of their positive modulation, through a dithiothreitol-induced reduction of the receptor redox site, on thermoregulation in rats maintained at an ambient temperature of 20-22 degrees C. Given intraperitoneally at the dose of 25 and 50 mg x kg(-1), dithiothreitol induced dose-dependent hypothermia. The prior administration of 0.5 mg x kg(-1) of (+/-)-dizocilpine maleate (MK801), a non-competitive glutamate NMDA receptor antagonist, blocked most of the dithiothreitol-induced hypothermia. MK801 given alone was followed by slight transient hyperthermia. This confirms the involvement of NMDA receptors in thermoregulation and suggests that they might be under redox modulation.

Nociceptive R3 reflex in relapsing-remitting multiple sclerosis patients.

Pain in multiple sclerosis (MS) patients has only recently been recognised as a genuine symptom of this disease. It is important to determine whether this pain is the consequence of another symptom of MS or whether it is due to a demyelinating lesion affecting pain pathways. A close relationship has been found between the R3 component of the blink reflex and the pain threshold. The aim of this work was to carry out an objective evaluation of the nociceptive system in MS patients by means of the R3 component of the blink reflex. The study was performed on 20 healthy volunteers and on 20 clinically defined relapsing-remitting MS patients with EDSS not > 3.5, normal R1 and R2 components of the blink-reflex, personal and family anamnesis negative for migraine and trigeminal neuralgia; the patients were not taking drugs at the time of the test. A significant difference was found, between healthy volunteers and patients, for R3 threshold, pain threshold and R3 latency.

[Stress echocardiography with dobutamine in the identification of coronary disease in patients with left bundle branch block]. / Ruolo dell'eco-stress con dobutamina nell'identificazione di malattia coronarica in pazienti con blocco di branca sinistra.

Left bundle branch block does not permit an easy diagnosis of coronary heart disease (CAD) with provocative non-invasive test such as bicycle or treadmill stress test. Echocardiography allows the identification of segmental wall motion by evaluating the movement as well the thickness of the segment examined. Due to its agonist action on beta 1 receptors, dobutamine causes an increase in myocardial oxygen consumption and, as a consequence, may reveal myocardial ischemia; on this basis, we evaluated the sensibility, specificity and diagnostic accuracy of dobutamine stress-echo in identifying CAD in patients with left bundle branch block, and compared results with those obtained from coronary catheterization. From February 1994 to September 1995 we observed 25 patients with left bundle branch block (17 men, 8 women, mean age 61.8 +/- 8.4 years, range 43.75), affected or suspected for CAD. All patients underwent dobutamine stress-echo test and coronary arteriography. We divided patients into two groups: the first one (11 patients) with acute myocardial infarction, the second one (14 patients) without previous ischemic episodes. Diagnostic accuracy, specificity and sensibility of the stress-echo test were evaluated in order to identify significant stenosis of the left anterior descending (LAD), right coronary (RCA), and/or circumflex artery (CA). Dobutamine stress echocardiography showed in all patients, from basal to peak, an increase in blood pressure (from 121.2 +/- 17.4 to 141.8 +/- 23.6 mmHg), heart rate (from 81.3 +/- 10.9 to 140.7 +/- 8.9 b/min), and double product (from 9861.1 +/- 1898.1 to 19976.6 +/- 3603.6). In 8 (32%) patients who had typical chest pain, 7 had CAD. In 17 (68%) patients without chest pain, 5 had CAD and 12 had normal coronary arteries. Dobutamine stress echocardiography showed segmental wall motion variations only in 13 patients; 12 of them had a significant stenosis of coronary artery relative to the ischemic area, the other 1 was a false positive. Coronary arteriography showed stenosis of LAD in 10 and of RCA and/or CA in 12 patients, in both groups dobutamine stress-echo test had 1 false negative. Dobutamine stress echocardiography showed high diagnostic value as a provocative non-invasive test for CAD in patients with left bundle branch block. In conclusion, or study shows that no statistical difference exists in identifying ischemia in identifying ischemia in the LAD territory compared to RCA and/or CA. Further investigations are need to confirm the higher diagnostic accuracy in patients with left bundle branch block and to establish whether lower specificity in patients with a previous myocardial infarction is due to the smaller number of patients or to methodology.

[Significance of hypotension and vasovagal reflex during echo-stress using high doses of dobutamine]. / Significato dell'ipotensione e del riflesso vaso-vagale durante eco-stress con alte dosi di dobutamina.

Coronary artery disease (CAD) is one of the main causes of cardiovascular morbility and mortality. Actual research lines are directed towards the discovery of silent CAD before hard events as myocardial infarction and sudden death. Dobutamine stress echocardiography is an useful method to assess patients with suspected CAD who, are not able to stand an effort because of physical reasons. During the test, hypotension and/or bradycardia may occur and may cause interruption of the test. The aim of our study was to consider prevalence, meaning and clinical implications of hypotensive, sometimes associated to bradycardia, during dobutamine stress echocardiography. From April 1994 to June 1996, 363 consecutive patients (267 men and 96 women with an average age of 59.3 +/- 10 year) were examined because of suspected or known ischemic cardiopathy. All patients underwent dobutamine stress echocardiography and coronary arteriography. Neither hypotension nor bradycardia was noted in 285 of our patients (78.51%), while in the remaining 78 patients (21.48%) there was a pressure drop > or = 20 mmHg; bradycardia appeared in 6 patients. The study shows that it does not exist a statistically significant difference between the percentage of the patients with CAD of the control group and those of the hypotensive group (91.9 vs 83.3%, NS). As for the changes in well motion score index, there was not a statistically significant difference between patients improved score index in the control group and in the hypotensive group (80 vs 74.3%, NS). The 6 patients with hypotension and bradycardia had normal coronary arteries. In the light of these results hypotension, alone or associated with bradycardia, should not be considered as a negative prognostic factor and should not induce to the interruption of the dobutamine stress echocardiography.

Regional specificity of the long-term variation of tyrosine hydroxylase protein in rat catecholaminergic cell groups after chronic heat exposure.

The present study was carried out to investigate the effect of chronic heat exposure on tyrosine hydroxylase (TH) protein content in catecholaminergic rat brain-stem areas such as the anterior (LCA) and posterior (LCP) locus coeruleus, the substantia nigra (SN), the ventral tegmental area, and the dorsomedial (DMM) and the ventrolateral medulla and in the adrenal gland (AG). Male Sprague-Dawley rats were exposed to 34 degrees C during 3, 7, or 14 days. Controls were kept at 25 degrees C for the same period. In the LCA, TH content was decreased on day 7 (-34%) and 14 (-37%) of heat exposure. In the SN, TH protein content was decreased on day 7 (-25%) and 14 (-20%) after 34 degrees C. In the DMM cell group, 14 days at 34 degrees C produced a decrease (-20%) of TH content. In all of these structures, TH content variations were correlated with body temperature variations. In the AG, TH content increased progressively to peak (+31%) after 14 days of chronic heat exposure. This increase was also associated with body temperature modification. The selective and body temperature-related response to long-term TH protein content variations following chronic heat exposure observed in the LCA, SN, DMM, and AG could represent an adaptive physiological response of these catecholaminergic cells.