Autoradiographic localization of dopamine D2-like receptors in the rabbit pulmonary vascular tree

In the present study, the pharmacological characteristics and the anatomical localization of dopamine D₂-like receptor sites in the extraparenchymal and in the intraparenchymal portion of the rabbit pulmonary artery were investigated using combined radioligand binding and light microscope autoradiography with [³H]-spiroperidol (spiperone) as a ligand. The ligand was bound to sections of the pulmonary artery in a manner consistent with the labelling of dopamine D₂-like receptors with an equilibrium dissociation constant (K _d) of about 2.4±0.07 nmol/l and a maximum density of binding sites of 65±4.5 fmol/mg tissue. In contrast, binding experiments made with sections of rabbit lung did not allow the evaluation of specific binding. Light microscope autoradiography showed the development of specific silver grains within the tunica adventitia of extraparenchymal branches of rabbit pulmonary artery and of large and, to a lesser extent, of medium-sized intraparenchymal branches of the pulmonary artery. No silver grains were found within small branches of the pulmonary artery or of the pulmonary vein. Development of adventitial silver grains was inhibited by compounds active at dopamine receptors. The greater sensitivity to displacement by domperidone, haloperidol, (–)-sulpiride and bromocriptine than to displacement byN-propyl-norapomorphine, quinpirole or clozapine suggests that the [³H]-spiroperidol binding sites observed in extraparenchymal, large and medium-sized branches of the pulmonary artery belong, probably, to the dopamine D₂ receptor subtype. The possible pre-junctional localization of these sites is discussed. Correspondence to: R Amenta     

Worker turnover because of spinal pathologies in the wards and outpatient clinics of the hospitals of Leno and Manerbo, Brescia]

A total of 306 employees of the hospitals of the Leno/Manerbio health area underwent clinical and anamnestic examination in order to ascertain the existence of degenerative diseases of the spine associated with "manual handling of loads" risk. The prevalences obtained for positive anamnestic threshold concerning the lumbosacral spine, the trend of total acute low back pain and of low back pain in the last year showed lower values compared to the entire national group and in any case lower or only slightly above the values for the reference group of non-exposed subjects. Therefore, in order to assess the real prevalences of disorders due to incorrect load handling in hospital environments, it is important to assess the presence of associated disorders of the spine also and especially in outpatients departments. In fact, unsuitable or unfit staff had recently been transferred from the wards to outpatients departments. 56 workers from outpatients departments underwent physical-anamnestic examination: 16 workers (4.5% of the entire group under study) from average-to-high risk wards were identified as suffering from degenerative disorders of the lumbosacral spine. Therefore the prevalence of unfit subjects from hospital wards, cancelling the effect of the turnover factor on outpatients departments, led to an almost twofold total frequency, which rose from 6.9% to 11.4%.     

Prevention of bleeding in aortic root surgery

Bleeding after aortic root replacement with a valved conduit may be problematic and difficult to control. A few technical details that may facilitate hemostasis in aortic root surgery are described.     

Use of the "single suture" technique to expose the anterior surface of the heart

The "single suture" technique, which consists of placing a suture in the oblique sinus of the posterior pericardium and connecting it to a vaginal tape, is commonly adopted in off-pump coronary artery revascularization to obtain elevation of the heart and coronary artery exposure. This report describes the use of this technique to expose the anterior wall of the heart in the setting of ventricular aneurysm repair.     

Hypermnesia in unilateral neglect

Thirteen right brain-damaged patients who were found to neglect pictures presented on the left of a display were presented the same stimuli, intermixed with foils, in a yes-no recognition test. Fifty per cent of patients claimed to have already seen one or more of the previously neglected pictures. This demonstrates that visual information that fails to access consciousness in neglect patients does retain the ability to surface as explicit memory at a later stage.     

Cervical myelopathy in mucopolysaccharidosis type IV

We describe our experience with 8 Italian patients having mucopolysaccharidosis type IV, diagnosed between 1 and 10 years of life, who presented odontoid hypoplasia causing cervical myelopathy. We discuss the possibility of cranio-cervical stabilization in order to reduce the neurological complications.     

Open and laparoscopic cholecystectomy in acquired immunodeficiency syndrome: indications and results in fifty-three patients

BACKGROUND: Although acute cholecystitis is one of the most common indications for abdominal surgery in patients with acquired immunodeficiency syndrome (AIDS), previous studies have reported disappointingly high morbidity and mortality among those patients who have undergone cholecystectomy. The aims of this study were to analyze the indications for and the outcome of cholecystectomy performed for acute cholecystitis in patients with AIDS. METHODS: We retrospectively reviewed the hospital charts of 53 patients with AIDS who underwent open or laparoscopic cholecystectomy from 1992 to 1997. Statistical analysis using the chi-square, Student's t, and Fisher exact tests was conducted to determine whether cause of cholecystitis, type of surgical approach, and CD4+ T-lymphocyte count influenced outcome. RESULTS: The clinical findings and imaging by ultrasonography were always reliable in establishing diagnosis and guiding treatment of acute cholecystitis. Open cholecystectomy was performed in 24 patients (45%). The procedure was begun laparoscopically in 29 patients (55%) and converted to open in 4 (14%). The pathologic findings showed acalculous cholecystitis in 19 patients (36%) and cholelithiasis in 32 (60%). Morbidity was 34% and mortality was 2%. Type of operative approach, cause of cholecystitis, and CD4+ T-lymphocyte count (greater or less than 50 cells/mm3) did not significantly affect morbidity and mortality. The length of hospital stay was significantly influenced by the CD4+ T-lymphocyte count. CONCLUSIONS: These findings suggest that in most patients with AIDS, laparoscopic or open cholecystectomy may be performed with significant but acceptable morbidity and low mortality.     

Histamine H2-receptor antagonists stimulate proliferation but not migration of human gastric mucosal cellsin vitro

Gastric mucosal cell migration and proliferation are crucial events in the repair of gastric mucosal erosions. This study was designed to test the hypothesis that the H₂ blockers roxatidine and ranitidine might stimulate migration and proliferation of gastric mucous cells derived from a human well-differentiated gastric adenocarcinoma cell line (MKN 28 cells)in vitro, in conditions independent of systemic factors and of acid inhibition. Confluent monolayers of MKN 28 cells were wounded with a razor blade and were then incubated with roxatidine or ranitidine. The number of cells migrating to the damaged area was determined 24 hr later. Cell proliferation was assessed by means of [³H]thymidine uptake and cell counts after incubation with roxatidine or ranitidine. Neither H₂ antagonist significantly stimulated cell migration. On the other hand, cell proliferation was dose-dependently and significantly enhanced by incubation with roxatidine and ranitidine. Exogenous administration of TGF- significantly stimulated MKN 28 cell division. However, incubation with roxatidine or ranitidine did not increase the steady-state mRNA expression of TGF- or EGFR as assessed by northern blot analysis. Based on thesein vitro findings, we postulate that the ulcer healing effect of these H₂ antagonistsin vivo might be due in part to stimulation of gastric mucosal cell proliferation.Data from this paper have been presented in part at the 1995 meeting of the American Gastroenterological Association and published in abstract form in Gastroenterology 108:A72, 1995.     

Myopathy and hypertrophic cardiomyopathy with selective lysis of thick filaments

We present a undescribed condition in a girl who died at 8 years of hypertrophic cardiomyopathy. Muscle and endomyocardial biopsies disclosed a selective loss of thick filaments ultrastructurally. In muscle biopsy histochemical abnormalities of myofibrillar AT-Pase were confined to type 1 fibres. Gel electrophoresis of muscle homogenate showed no qualitative abnormalities of slow and fast myosin heavy chains (MHC) and light chains, and the amount of the different myosin isozymes was in agreement with histochemical myofibrillar ATPase findings. The pathogenetic mechanisms have not been elucidated in this case but we suspect an abnormality of the-cardiac MHC gene, the only gene expressed in the heart and in type 1 skeletal muscle fibres.     

Functional evaluation of the perineum in pregnancy. Inversion of control

This study concerns clinical data of 142 women, who were subjected to functional evaluation of perineum during the last part of pregnancy. The 16 cases characterized by synergic activation, during the examination of perineal muscles ("perineal testing"), of antagonist muscles ("inverted control"), were examined taking into account data regarding evolution of labour and perineal outcome. "Inverted control" seems to influence, in this study, length of the second stage and frequency of operative deliveries whereas we can't confirm the importance of this disorder within pathogenesis of perineal obstetric complications.