Evidence for the presence of both pre- and postjunctional P2-purinoceptor subtypes in human isolated urinary bladder.

1. In order to characterize P2-purinoceptor(s) in human urinary bladder the contractile effects of ATP and its slowly-hydrolyzable analogues alpha, beta-methylene ATP (alpha, beta-MeATP) and beta, gamma-methylene ATP (beta, gamma-MeATP) were investigated on human detrusor strips taken from patients undergoing cystectomy for bladder carcinoma. 2. Serial concentration-response curves (SCRC) for ATP, alpha, beta-MeATP and beta, gamma-MeATP were constructed with an interval of 25 min between two successive doses to avoid tachyphylaxis. ATP (10 microM-10 mM) induced a phasic contraction, which was very rapid in onset. The dose-response curve to ATP appeared not to be monophasic: at the lower concentrations (10-300 microM) the curve was shallow, whilst at high concentrations (1-10 mM) the curve was steeper. The magnitude of the response obtained at the highest concentration tested (10 mM) was only 21.1 +/- 2.8% (mean +/- s.e. mean; n = 4) of the KCl (100 mM)-induced contraction. 3. alpha, beta-MeATP (0.3 microM-1 mM) and beta, gamma-MeATP (10 microM-1 mM) elicited a phasic contraction with a time course similar to that exhibited by ATP. The magnitude of the response obtained at the highest concentration tested (1 mM) was 70.3 +/- 6.3% for alpha, beta-MeATP (n = 10) and 27.9 +/- 4.5% for beta, gamma-MeATP (n = 8) of KCl (100 mM)-induced contraction. The rank order of potency was alpha, beta-MeATP > beta, gamma-MeATP > ATP. A plateau of response could not be achieved by any of these agonists.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cholesterol crystals in biliary microlithiasis

A recent study put forward the hypothesis that microlithiasis may represent an early stage in the development of biliary calculi. It is an established fact that cholesterol crystals are the product of an inevitable stage in the sequence leading to gallstone formation. To test the hypothesis stated above ten patients affected by gallbladder cholesterol microlithiasis (CM) were examined in the lipid composition of the bile, the cholesterol saturation index and the presence of cholesterol crystals being calculated. The results were compared with those of 14 patients affected by pigment microliths, 24 with larger stones (LS) and ten control patients. The cholesterol saturation index was above one in all CM patients, whereas in some LS patients the gall-bladder bile was not supersaturated. Cholesterol crystals were observed in the gallbladders of all CM patients and seven LS patients. These results would seem to provide support for the hypothesis of microcalculi as being "young stones", with the bile of CM patients maintaining the conditions leading to gallstone formation.     

The UTX gene escapes X inactivation in mice and humans

We recently have identified a ubiquitously transcribed mouse Y chromosome gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A peptide derived from the UTY protein confers H-Y antigenicity on male cells. Here we report the characterization of a widely transcribed X-linked homologue of Uty , called Utx , which maps to the proximal region of the mouse X chromosome and which detects a human X-linked homologue at Xp11.2. Given that Uty is ubiquitously transcribed, we assayed for Utx expression from the inactive X chromosome (Xi) in mice and found that Utx escapes X chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the mouse X chromosome have been reported previously to escape inactivation. The human UTX gene was also found to be expressed from Xi. We discuss the significance of these data for our understanding of dosage compensation of X-Y homologous genes in humans and mice.      

Long-term ethanol administration enhances age-dependent modulation of redox state in different brain regions in the rat: protection by acetyl carnitine

Chronic alcoholism is a major public health problem and causes multiorgan diseases and toxicity. Although the majority of ethanol ingested is metabolized by the liver, it has intoxicating effects in the brain. Evidence is accumulating that intermediates of oxygen reduction may be associated with the development of alcoholic disease. Several studies have shown the capacity of carnitine and its derivatives to influence ethanol metabolism. We have previously demonstrated that preadministration of L-carnitine to rats receiving ethanol significantly reduced fatty acid ethyl esters in different organs and that the carnitine/acylcarnitine system is crucial for maintaining a functional acetyl-CoA/CoA ratio under conditions in which cellular homeostasis is exposed to the deleterious effects of accumulating organic acids. Ethanol, administered to rats for 20 months, induced significant changes in the status of glutathione, primarily in the brain regions of hippocampus and cerebellum, followed by cortex and striatum, where a decrease in reduced glutathione (GSH) and the GSH/oxidized glutathione ratio was found. The same brain regions showed a significant increase in free radical-induced luminescence and hydroxynonenal (HNE), which were associated with decreased GSH reductase activity. Long-term supplementation with acetyl carnitine significantly reduced GSH depletion, particularly in the brain regions of hippocampus, an effect associated with decreased luminescence and HNE formation. In addition, acetyl carnitine treatment increased GSH reductase and arginase activities. Our results indicate that decreased GSH reductase activities associated with thiol depletion are important factors sustaining a pathogenic role in alcohol-related pathologies. Administration of acetyl carnitine greatly reduces these metabolic abnormalities. This evidence supports the pharmacological potential of acetyl carnitine in the management of alcoholic disturbances.     

Long-term ethanol administration enhances age-dependent modulation of redox state in brain and peripheral organs of rat: protection by acetyl carnitine

Evidence is accumulating that intermediates of oxygen reduction may be associated with the development of alcoholic disease. Free radical-induced perturbation of the oxidant/antioxidant balance in the cell is widely recognized as the main causative factor of age-related disorders. In the present study we investigated the effects of 20 months of ethanol consumption on the antioxidant defense system in different rat organs compared with normal aging in the absence and presence of treatment with L-acetyl carnitine. We demonstrate that aged rats underwent significant perturbation of the antioxidant defense system, as indicated by depletion of reduced glutathione (GSH) content, increased oxidized GSH, free radical-induced luminescence associated with increased hydroxynonenal content and decreased GSH reductase activity. These modifications, observed particularly in brain and liver compared with other organs, were enhanced by long-term alcohol exposure and, interestingly, were significantly reduced with acetyl carnitine supplements. Our results indicate that decreased GSH reductase activity and thiol depletion are important factors in effecting a pathogenic role for oxidative stress in aging and in all situations in which age-correlated and oxidant-induced changes occur, such as in alcoholism. Administration of acetyl carnitine greatly reduces these metabolic abnormalities. Our findings support its pharmacological potential in the management of alcoholic disturbances.     

Analysis of nandrolone esters in oily injections by reversed-phase high-performance liquid chromatography

A specific liquid chromatographic (HPLC) procedure is presented for the analysis of nandrolone esters (phenylpropionate, decanoate and undecanoate) in commercial oily injections. The analysis was carried out under isocratic, reversed-phase (RP8 column) conditions using a UV detector (240 nm). The system discriminates between nandrolone alcohol, a potential impurity, and its esters and permits the quantitation of trace benzaldehyde derived from the oxidative degradation of benzyl alcohol. The proposed HPLC method was found to be more specific and accurate than the pharmacopoeial spectrophotometric assay procedure (isoniazid reagent). The interference of benzaldehyde with the isoniazid method was also investigated.     

Adoptive Immunotherapy With Tumor-Infiltrating Lymphocytes and Subcutaneous Recombinant Interleukin-2 Plus Interferon Alfa-2a for Melanoma Patients With Nonresectable Distant Disease: A Phase I/II Pilot Trial

Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 10⁶ IU/m²/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 10⁶ IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 10⁹ (range, 1–43 × 10⁹), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 10⁶ IU/m²/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.     

Target controlled infusion (TCI): applications of the "TCI visual" program in anesthesia and sedation with propofol

BACKGROUND: Systems for Target Controlled Infusion accepting not only patient' data, like Diprifusor, but also a pharmacokinetic model have not been available in Italy in the last years. Therefore a program which controls a Pilot Anesthesia Vial pump and accepts any pharmacokinetic model was developed and applied to propofol infusion for anaesthesia and sedation. METHODS: Two versions of the Visual TCI program have been developed. The first, at intervals, supplies the anaesthetist with the values for the pump; the second directly interacts with the pump. The program also supplies the anaesthetist with the current amount of drug in each compartment and with the estimated awakening time. DESIGN: preliminary prospective study. SETTING: operatory theatre and Intensive Care Unit in a University Hospital. Patients: 6 patients undergoing total intravenous anaesthesia with propofol and fentanyl for abdominal surgery; 6 patients undergoing sedation with propofol in an Intensive Care Unit (the first 4-hour period was taken into account). Interventions: propofol infusion was regulated by the Visual TCI program. The first version was employed in three patients of each group and the second one in the others. Hypo- and hypertensive episodes (systolic pressure less than 80 mmHg or higher than basal value plus 25%) were recorded during anaesthesia and sedation. Propofol concentration was measured in plasma three times at defined intervals and per cent differences between measured and computer-calculated values (Predictive error, PE) were calculated. RESULTS: No hypo- or hypertensive episodes were recorded. PE was 27.4 +/- 17.9%. CONCLUSIONS: The program was easily employed, caused no inconvenience, and its use was associated with a remarkable cardiovascular stability. PE distribution was acceptable on the ground of the criteria reported in the literature. The program can be applied to drugs other than propofol, with both two and three compartment pharmacokinetic models and the anaesthetist can choose the most suitable model for the patient.     

Five-year Prospective Audit of Routine Intravenous Cholangiography and Selective Endoscopic Retrograde Cholangiography with or without Intraoperative Cholangiography in Patients Undergoing Laparoscopic Cholecystectomy

Consensus has never been reached regarding the need or the imaging technique for evaluating the common bile duct (CBD) in patients considered for cholecystectomy. With the advent of laparoscopic cholecystectomy there has been a resurgence of interest in the role of preoperative intravenous cholangiography (IVC) as an alternative for evaluating the CBD. The purpose of this audit was to assess whether a diagnostic workup based on IVC, which permits selective use of intraoperative cholangiography (IOC) and endoscopic treatment of CBD stones before surgery, could be useful in patients undergoing laparoscopic cholecystectomy (LC). In patients without jaundice, gallstone pancreatitis, a prior diagnosis of CBD stones, a prior history of contrast allergy, or a risk of contrast-associated acute renal failure, IVC was performed routinely. Patients suspected to have CBD stones based on IVC results or with inconclusive IVC and patients with a strong clinical suspicion of CBD stones were referred for endoscopic retrograde cholangiography (ERC). IOC was carried out in patients who had a history of contrast allergy or risk of contrast-associated acute renal failure and whenever the surgeon was in doubt as to the biliary anatomy or CBD clearance. IVC was carried out in 1155 patients, ERC in 225, and IOC in 54. IVC was conclusive in 1132 patients, with a diagnostic accuracy of 99%. Our workup permitted the sequential endoscopic-laparoscopic treatment of cholecystocholedocholithiasis in 162 cases. During the follow-up period residual CBD stones were detected in four patients. Our diagnostic workup showed that routine IVC exposes the population to a large radiation burden, and the cost is high for the small number of patients who benefit. Moreover, it does not seem helpful in reducing the incidence of CBD injuries during LC.