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Objectives: a positive correlation between cholesterol esterification, acyl-CoA:cholesterol acyltransferase (ACAT), multidrug resistance (MDR1) gene expression and atherosclerotic lesions has been shown in human arteries. The objective of this study was to map the expression of MDR1, ACAT genes and the cholesteryl ester content in normal, atherosclerotic and varicose human vessels. Materials: vascular segments were obtained from seven cadaveric donors, 27 patients undergoing vascular surgery for severe atherosclerotic disease and 11 patients with saphenous vein varicosities. Methods: lipid analysis and RT-PCR of MDR1 and ACAT mRNAs were performed. Results: an increase in cholesteryl ester content and in ACAT and MDR1 expression was demonstrated in relation to the age in the arteries prone to atherosclerosis; this expression was maximal in arteries from symptomatic patients. In resistant arteries and in veins cholesteryl ester accumulation was rare and light, while ACAT and MDR1 expression was not related to the age of the subjects. Conclusions: the results showed that an increase in MDR1 and ACAT expression may be responsible for the accumulation of cholesteryl esters as well as for cell growth rate acceleration in vessel sites prone to atherosclerosis.

Several studies have shown that pituitary adenylate cyclase activating polypeptide (PACAP) stimulates at very low concentration insulin release from pancreatic beta cells. In addition, PACAP has been evidenced in pancreatic nervous fibers surrounding the islets, the core of the islet, and the capillaries. The aim of the present study was to demonstrate internalization of PACAP in pancreatic islet cells. Pancreatic islets were obtained from Wistar rat pancreata by modified Lacy's isolation method. The isolated islets were incubated in the presence of Fluo-PACAP 27, a fluorescent ligand specific for PACAP receptors. At the end of incubation the islets were fixed in paraformaldehyde and then observed by confocal microscope. Fluo-PACAP 27 was internalized into pancreatic islet cells, and this process was time- and temperature-dependent (37 degrees C). The fluorescent molecules converged toward the nucleus where an intense fluorescence was evidenced after 60 minutes. Incubation with phenyl arsine oxide as well as with PACAP 6-38, a receptor antagonist, prevented the internalization process. Further studies are required to explain the internalization process of PACAP 27 into the nucleus of pancreatic islet cells.

Recent studies have shown that a membrane p-glycoprotein, encoded by MDR1 gene, is involved in the transport of free cholesterol from the plasma membrane to endoplasmic reticulum, the site of cholesterol esterification by acyl-CoA:cholesterol acyltransferase (ACAT). Moreover, results deriving from our previous studies have shown that the rate of cell proliferation was positively correlated with cholesteryl ester levels as well as with ACAT and MDR1 gene expression. In this study, lipid content and the expression of the genes involved in cholesterol metabolism such as hydroxy-methylglutaryl coenzyme A reductase (HMGCoA-R), low-density lipoprotein receptor (LDL-R), ACAT and MDR1 have been investigated in control and atherosclerotic arteries. The results have shown that the levels of cholesteryl ester increase with the age of cadaveric donors in arteries prone to atherosclerosis (abdominal aorta, superficial femoral artery) and become predominant in advanced atherosclerotic lesions. The mRNA levels of ACAT and MDR1 showed the same age correlation, reaching the highest values in atherosclerotic specimens. These results suggest that MDR1 may be involved in the accumulation of intracellular cholesterol ester levels found in atherosclerotic lesions. Moreover, the levels of HMGCoA-R, LDL-R and ACAT gene expressions progressively increased with the age of cadaveric donors; conversely, in atherosclerotic specimens, the mRNA levels of HMGCoA-R and LDL-R drastically decreased while ACAT gene expression reached its maximum. These findings suggest a reactivation of normal homeostatic regulation of cholesterol in advanced and complicated lesions.

This paper describes a method for pig islet isolation with the following original features: first, we set up a reproducible, rapid, sterile, and simple method for pancreas procurement and preparation with double duct incannulation. Second, we demonstrated that UW solution can be used for pancreas digestion; third, we designed an original method for pancreas digestion, derived from the method originally described by Ricordi, except that a double digestion circuit made it possible to digest continuously, within one step, the pancreas, which makes the method operator-independent; finally we designed a simple method for islet purification based on a two-layer Histopaque/ UW density gradient and the use of the COBE 2991 cell processor.

Chronic venous ulcer treatment is often time consuming and requires a high degree of compliance from the patient. This derives not only from venous hypertension but also from chronic structural and metabolic changes of underlying tissues which impair the healing process. It therefore becomes necessary to improve the ulcer tissue condition in order to accelerate the healing process. This is obtained mainly with the improvement of local haemodynamics and secondly by direct action on the ulcer. The aim of the study is to evaluate the efficacy of a treatment with a pedunculated flap of fascia as an additional treatment of chronic venous ulcer.Four patients classified C6 according to the CEAP classification were treated for chronic venous ulcer with correction of venous hypertension (saphenectomy or ligature of incompetent perforating veins). The patients also underwent rotation of a fascial pedunculated flap transferred from the sural area to the perimalleolar area. After 7-15 days they had a free skin graft in the treated area.All patients were discharged on the 3(rd) postoperative day after the flap rotation. In 3 patients the ulcer healed within 30 days and in a 4(th) patient within 45 days. No recurrence was observed.With this method the healing time seems to be shortened compared to the typical evolution in patients treated with only reflux control followed by conservative therapy. Associating fascial flap in the treatment of chronic venous ulcers improves the bed on which the free skin graft is applied. We can also hypothesize that this procedure restores the aponeurotic barrier between deep venous circulation and superficial microcirculation with the ensuing improvement in local venous hypertension.

Cholesterol esterification and smooth muscle cell (SMC) proliferation are the crucial events in the development of atherosclerotic lesions. The objective of this study was to analyse cholesterol esterification and the expression of MDR1 (multidrug resistance), ACAT (acyl-CoA:cholesterol acyltransferase) and caveolin-1 genes in atherosclerotic and healthy vascular walls, in SMCs obtained from atherosclerotic lesions and saphenous veins. Results demonstrated higher levels of cholesterol esters, ACAT and MDR1 mRNAs and lower levels of caveolin-1 mRNA in atherosclerotic segments compared to adjacent serial sections of the same artery and the corresponding non-atherosclerotic arteries from cadaveric donors. SMCs isolated from atherosclerotic plaques manifested an increased capacity to esterify cholesterol and to grow at a faster rate than SMCs isolated from saphenous veins. In addition, when SMCs from atherosclerotic plaques were cultured in the presence of progesterone, a potent inhibitor of cholesterol esterification, significant growth suppression was observed. An increase in ACAT and MDR1 expression and a concomitant decrease in caveolin-1 expression were also observed in SMCs isolated from atherosclerotic arteries as early as 12 h after serum stimulation. An opposite pattern was found when SMCs were treated with progesterone. These findings support the idea that cholesterol esterification plays a role both in early atherogenesis and in clinical progression of advanced lesions and raise the possibility that the cholesterol ester pathway might directly modulate the proliferation of SMCs.

This report describes the successful surgical treatment of a ruptured aneurysm of the left gastroepiploic artery. These aneurysms represent a very small fraction of visceral aneurysms.

Recent studies have shown that a membrane p-glycoprotein, encoded by MDR1 gene, is involved in the transport of free cholesterol from the plasma membrane to endoplasmic reticulum, the site of cholesterol esterification by acyl-CoA:cholesterol acyltransferase (ACAT). Moreover, results deriving from our previous studies have shown that the rate of cell proliferation was positively correlated with cholesteryl ester levels as well as with ACAT and MDR1 gene expression. In this study, lipid content and the expression of the genes involved in cholesterol metabolism such as hydroxy-methylglutaryl coenzyme A reductase (HMGCoA-R), low-density lipoprotein receptor (LDL-R), ACAT and MDR1 have been investigated in control and atherosclerotic arteries. The results have shown that the levels of cholesteryl ester increase with the age of cadaveric donors in arteries prone to atherosclerosis (abdominal aorta, superficial femoral artery) and become predominant in advanced atherosclerotic lesions. The mRNA levels of ACAT and MDR1 showed the same age correlation, reaching the highest values in atherosclerotic specimens. These results suggest that MDR1 may be involved in the accumulation of intracellular cholesterol ester levels found in atherosclerotic lesions. Moreover, the levels of HMGCoA-R, LDL-R and ACAT gene expressions progressively increased with the age of cadaveric donors; conversely, in atherosclerotic specimens, the mRNA levels of HMGCoA-R and LDL-R drastically decreased while ACAT gene expression reached its maximum. These findings suggest a reactivation of normal homeostatic regulation of cholesterol in advanced and complicated lesions.

Iloprost, a prostaglandin I2, is chemically stable and it has been successfully used by intravenous infusion in severe limb ischemia. Usually Iloprost is diluted in 0.9% sodium chloride solution and infused intravenously for six hours each day for 28 days in hospital.In the present study after the first three days of infusion with a traditional pump in hospital, a home pump has been utilised for the infusion of Iloprost at home. This device allows the continue infusion of Iloprost at a flow rate of 2 ml/h for six days, then the pump is filled with a new solution. The home pump consists of a protective shell in polycarbonate (10 x 12 cm), 270 ml of volume, inside there is a balloon reservoir (3 membranes) which is filled with Iloprost. The structure of Iloprost does not change into the home pump as evidenced by HPLC studies and its continue infusion allows plasmatic high levels of its active isomers during the 28 days of therapy. In 30 patients, 25 men and 5 women (mean age 61 years) with Fontaine stage IIB (6), III (5) and IV (19) POAD Iloprost has been infused with the home pump. The follow-up period was 1 to 16 months.The results have shown 4 major amputations and 1 death, in 9 patients complete pain relief and ulcer healing, and in 6 patients only improvement in relief of rest pain and ulcers.All the patients appreciated this system of infusion because they had a normal life; in addition it is less expensive because the patients stay in hospital only 3 days.

Microencapsulation of islets of Langerhans has been proposed in order to prevent immune rejection and possible recurrence of autoimmune disease. This study introduces a fast simple one-step microencapsulation procedure which allows the production of small sized barium-alginate beads. The volume of the microcapsules produced was approximately that of the encapsulated islets. Consequently, the insulin kinetics and the oxygen diffusion were favoured, while the transplanted tissue volume was reduced. Electron microscopy and immunoisolating testing were performed to evaluate the molecular cut-off, the physical and chemical characteristics of these microcapsules. Immunohistochemical staining and perifusion experiments of microencapsulated pancreatic islets showed their viability after the encapsulation procedure as well as in vivo experiments. In fact, microencapsulated porcine islets were implanted intraperitoneally into streptozotocindiabetic rats. The xenografts reversed the hyperglycemic state and functioned for a period ranging from 9 to 385 days. The low mannuronic acid concentration and the purity grade of the alginate, exerted a combined influence on the capsule biocompatibility as in vivo studies showed

Results of clinical islet transplantation remain disappointing despite the advances in islet technology. Availability of human organs and control of rejection by adequate immunosuppressive therapy remain the unsolved problems. Transplantation of xenogeneic tissue enclosed in immuno-separating membranes without immunosuppressive drugs may be a solution. In the present study porcine pancreatic islets were isolated by semiautomated method and purified utilizing discontinuous Euroficoll gradients on IBM 2991 cell separator. The porcine pancreatic islets were encapsulated with a new one-step method utilizing a home-made droplet generator. Each microcapsule contained one or two islets and microcapsule diameter was approximately that of the islets. This condition allows an optimal diffusion of insulin, glucose, nutrients and oxygen. Consequently, perifusion experiments with encapsulated porcine islets revealed a typical biphasic pattern of insulin release as it was seen in unencapsulated controls. Human erythrocytes were encapsulated and incubated with serum containing hemolysins and complement. These experiments showed that the encapsulated erythrocytes were protected against the hemolytic activity of Ig G and complement fractions. In conclusion, this encapsulation procedure allows the production of a very thin barium alginate membrane around the islets with very little increase of the total volume of transplanted tissue.

Diaphragmatic injuries due to blunt trauma are steadily related to a high mortality. Their diagnosis may be difficult, due to the lack of specific symptoms and, more frequently to the high incidence of coexisting lesions which can mask the clinical appearance. This work presents the main aspects of ten cases admitted to the Emergency Surgery Division of Cagliari (USL 21), during the last seven years, with a review of the literature.

Hydatidosis is particularly widespread in some geographic areas. Among these Sardinia presents one of the highest incidences. The authors examine the results obtained of 382 patients submitted to surgery between 1973 and 1989. The average age was 38.9 years. Liver involvement was observed in 215 cases, lung involvement in 167 cases, while localizations in other organs were rare. Forty liver cysts and 54 lung cysts were complicated preoperatively. The patients were submitted predominantly to total or subtotal cysto-pericystectomy (270 cases), parenchymal resection (75 cases), simple cystectomy (40 cases). Total postoperative mortality was 2.35%. Postoperative time was significantly shorter after cysto-pericystectomy and after parenchymal resection than after simple cystectomy. Patients suffering from multiple or complicated cysts were given supplementary chemotherapy.

This report describes 51 vascular patients with peripheral vascular disease treated intraoperatively by means of the autotransfusion apparatus with a minimum of 750 cc of reinfused blood. An early decrease of Hct, Hb, RBC, fibrinogen and Plt count was observed without any significant coagulation disorder.

The purpose of the present study was to investigate the effect of atenolol, a beta 1-selective blocker, along with flunarizine, a calcium antagonist, in the management of Raynaud's disease. Forty patients with Raynaud's disease were randomized into a trial in which atenolol (50 mg daily) was given with flunarizine (10 mg daily). During the trial all patients were subjected to finger photoplethysmography and were given a diary to note daily the number and duration of the crises and presence or absence of pain and paresthesia. The association of atenolol with flunarizine caused an 80% reduction in the number of vasospastic crises, a significant increase (p less than 0.001) in the photoplethysmographic wave amplitude, and complete disappearance of pain and paresthesia. These results were not observed in patients treated with a placebo. Flunarizine reinforces the action of atenolol in causing a decrease in vasoconstriction in patients with Raynaud's disease, as observed previously by us, in that it acts directly on the beta-presynaptic receptors or on the calcium slow channels connected to the beta-receptors. The present study confirms that the principal role in the physiopathologic progression of Raynaud's disease seems to be played by a modification of the beta-presynaptic receptors in the nerve endings of the peripheral vessels.

Dopamine-induced vasodilatation in the renal artery of the dog is reversed by chlorpromazine while the vasodilatation produced by isoprenaline is not. Pronethalol has the entirely opposite actions on this preparation. The infusion of dopamine into the renal artery enhances the kidney output of water, sodium, potassium and urea. These effects are also reversed by chlorpromazine.

d -Penicillamine inhibits poliovirus growth in vitro. This effect is related to a parallel inhibition of viral RNA synthesis. d -Penicillamine possesses a very narrow antiviral spectrum. In fact it exerts a weak inhibition against Coxsackie and ECHO viruses and shows no inhibitory effect against herpes simplex, vaccinia, and vesicular stomatitis viruses. The inhibitory action of d -penicillamine is suppressed by phenylalanine, tyrosine, tryptophan, and leucine and by Cu and Fe salts. l -penicillamine is ineffective as an antiviral agent.

A retrospective analysis is presented of 195 consecutive patients with chest trauma, hospitalized from 1976 to 1984 at the Institute of Pathology and Surgery of the University of Cagliari. The most frequent causes were traffic accidents. In 11 patients the trauma was penetrating while 184 presented with blunt trauma. Conservative treatment was performed in 106, pleural drainage or thoracentesis in 29, and surgery in 60. Early osteosynthesis was performed in the 22 patients with flail chest and in 15 with multiple depressed fractures. Total mortality was 4.1%, and 13.6% in patients with flail chest. All deaths were associated with significant extrathoracic injuries.

This report concerns the results of a study carried out to show the presence of presynaptic Beta adrenergic receptor supersensitivity in RD patients and the possibility to prevent or at least decrease this supersensitivity with Beta-blocker treatment. It is shown that the paradoxical vasoconstriction response to ISP infusion can be prevented in RD patients by the acute administration of Beta-blocker, such as Atenolol or DL Propranolol. Moreover, chronic treatment with the correct Beta-blocker was seen to prevent angiospastic crisis in these patients.

Substance P-like immunoreactive nerve fibres and terminals are found in the human sympathetic paravertebral ganglia in connection with postganglionic neurones. Substance P may act as neurotransmitter or neuromodulator in the autonomic transmission in man.

The stereomorphological arrangement of skeletal muscle capillaries depends on many factors. Genetic biochemical composition of muscle fibers, age, and training can interfere with the growth of the capillary network. This study is focused on the age effect of chronic reduction of blood flow, as in arterial stenosis, in skeletal muscle network of young rats when compared with adult rats. It has been observed that there is a statistically significant decrease of the length of short capillaries which cross the muscle fibers. In adult rats the opposite occurs.

The presence of substance P- and enkephalin-like immunoreactive nerve fibers and terminals is demonstrated in the human paravertebral sympathetic ganglia by an indirect immunofluorescence technique. Substance P-positive nerve structures appear in the form of fiber bundles, isolated varicose filaments and dot-like and basket-like nerve terminals around the neuronal cell bodies. Their density shows a remarkable individual variability. Enkephalin-positive nerve structures appear as isolated varicose filaments and dot-like nerve terminals, forming densely innervated patchy areas. No substance P- or enkephalin-containing cell bodies were detected. No overlapping seems to exist among the areas innervated by the two types of neuropeptides.

The vascular beds of femoral biceps, soleus, and medial gastrocnemius of the rat were perfused with India ink to outline the capillary network. Histologic cross sections were stained with picric acid and basic fuchsin. By this method, the muscle fiber nuclei appeared red and could be clearly distinguished from the darker-stained capillary profiles. A specific anatomic relationship between capillaries and muscle fiber nuclei was tested against a random orientation by an analysis of independence. Systematic sampling was performed by positioning the center of an eyepiece reference circle on the uppermost point of each fiber profile. The frequencies of the four combinations (fiber nuclei and/or capillaries or neither) found within each test circle were recorded and stored in 2 × 2 contingency tables. The Z test of independence revealed a highly significant relationship between capillaries and fiber nuclei in all muscles examined. The nonrandom nucleus-related location of capillaries around muscle fibers was even more evident after pooling the individual muscle data in a single table ( P ⪡ 0.00001). These findings suggested a chemotactic attraction of capillaries by the muscle fiber nuclei. This observation is supported by the high concentration of cytoplasmic organelles present in nuclear regions of skeletal muscle fibers, that is well documented in the literature. These organelles may be responsible for the production and local secretion of chemotactic factors “to attract” capillaries, and hence provide for their characteristic orientation and distribution in muscle.

THE presence of a guanidine moiety in a number of antiviral drugs1–5 prompted us to investigate whether some simple guanidine derivatives may reduce the infectivity of viruses for cultured mammalian cells. The following compounds were examined: guanidine hydrochloride, aminoguanidine bicarbonate, creatine hydrate, arginine, uridine, urea, thiourea, decyl- and dodecyl-bis-guanidine, N,N′-bis(beta-hydroxyethyl)biguanide. The chemicals dissolved in water were boiled for about 15 min. and then added to the culture media.

PREVIOUSLY1,2 we have shown that guanidine possesses a strong and highly specific inhibitory action against enteroviruses. This antivirus activity of guanidine seemed to us of interest due to: (1) its specificity; (2) the simplicity of guanidine molecule; (3) the ability of guanidine to stop the cytotoxic effect of poliovirus even when added to cell cultures which were infected several hours previously.