Combining in the melt physical and biological properties of poly(caprolactone) and chlorhexidine to obtain antimicrobial surgical monofilaments.

Bacterial infections on a sutured wound represent a critical problem, and the preparation of suture threads possessing antimicrobial properties is valuable. In this work, poly(caprolactone) (PCL) monofilaments were compounded at the concentration of 1, 2 and 4 % (w/w), respectively, to the antiseptic chlorhexidine diacetate (CHX). The incorporation was carried out in the melt by a single-step methodology, i.e. "online" approach. Mechanical tests revealed that the incorporation of CHX does not significantly change tensile properties of PCL fibres as the thermal profile adopted to prepare the compounded fibres does not compromise the antibacterial activity of CHX. In fact, CHX confers to compounded PCL fibres' antimicrobial property even at the lowest CHX concentration as revealed by microbiological assays performed on Escherichia coli, Micrococcus luteus and Bacillus subtilis strains. The scanning electron microscope micrographs and energy-dispersive X-ray analysis of compounded threads revealed that CHX is uniformly distributed on fibre surface and that the overall amount of superficial CHX increases by increasing compounded CHX concentration. This distribution determines a biphasic CHX release kinetics characterized by an initial rapid solubilisation of superficial CHX micro-crystals, followed by a slow and gradual release of CHX incorporated in the bulk. Interestingly, the compounded threads did not show any toxic effect compromising cell viability of human fibroblasts in vitro, differently from that observed using an equal amount of pure CHX. Thus, this study originally demonstrated the effectiveness of an "online" approach to confer antimicrobial properties to an organic thermoplastic polymeric material commonly used for medical devices.

Impacts of marine aquaculture at large spatial scales: evidences from N and P catchment loading and phytoplankton biomass.

While several studies point at off-shore aquaculture as a possible source of impacts on the local marine environment, very few have analysed its effects at large scales such as at the bay, gulf or basin levels. Similar analyses are hampered by the multiple sources of disturbance that may concomitantly affect a given area. The present paper addresses these issues taking the Gulf of Castellammare (Southern Tyrrhenian Sea) as an example. Nitrogen (N) and phosphorous (P) loads were calculated for the period 1970-2007, and compared to chlorophyll-a concentration as measured inside and outside the Gulf over the same period. Results indicate that N and P catchment loading has constantly decreased because of improved environmental management. Nevertheless, nutrient concentration in the Gulf has steadily increased since the establishment of aquaculture facilities in 1999. Chlorophyll-a concentration followed this trend, showing a marked increase from 2001 onwards. In the same period, chlorophyll-a concentrations measured inside and outside the Gulf have significantly diverged. As all the other possible causes can be ruled out, aquaculture remains the sole explanation for the observed situation. This paper demonstrates for the first time ever that off-shore aquaculture may affect the marine ecosystem well beyond the local scale and provides an additional element of concern to be kept into consideration when allocating oceans' space for new fish-farming activities.

Gastrointestinal stromal tumors (GISTs): focus on histopathological diagnosis and biomolecular features.

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors of the gastrointestinal tract that are believed to originate from a neoplastic transformation of the intestinal pacemaker cells (interstitial cells of Cajal) normally found in the bowel wall or their precursors. Although the microscopic features have been known for a long time, the defining characteristic of GIST is the presence of the cell-surface antigen CD117 (KIT), which is demonstrated by immunohistochemistry. KIT, which is a growth factor transmembrane receptor, is the product of the proto-oncogene c-kit (chromosome 4). Surgical removal remains the only curative treatment for patients with GISTs. Tumor size, mitotic index, anatomic location, tumor rupture and disease-free interval are the classic characteristics used to predict the clinical course of patients who undergo complete gross resection. Most GISTs express constitutively activated mutant isoforms of KIT or kinase platelet-derived growth factor receptor alpha (PDGFRA) that are potential therapeutic targets for imatinib mesylate. Imatinib mesylate is a rationally designed, molecularly specific oral anticancer agent that selectively inhibits several protein tyrosine kinases central to the pathogenesis of human cancer and which has demonstrated remarkable clinical efficacy in patients with chronic myeloid leukemia and malignant GISTs. More recently Sunitinib, a new KIT/PDGFRA kinase inhibitor, has been tested in patients with GIST resistant to imatinib, with promising results.

Prolonged mivacurium-induced neuromuscular block. Case report.

A 38-year-old white male patient was admitted to the hospital for elective surgery. General anesthesia was performed with propofol, alfentanil, nitrous oxide and mivacurium as neuromuscular blocker. Seven months before he had the same surgery without anesthetic problems (he received: propofol, vecuronium bromide, fentanil, nitrous oxide). Neuromuscular monitoring was carried out because the patient was included in a study assessing the clinical effect of mivacurium in microlaryngoscopy surgery. After mivacurium administration the first signs of recovery from neuromuscular block were observed after 255 min. The tracheal tube was withdrawn after 410 min from mivacurium administration, at this time the T1 was 80% of the control values and 7 min later the T1 reached 98%.

Sex differences in anterior commissure size in the rat.

Earlier studies have shown that the corpus callosum of rats tends to be larger in males than in females. We report here that the anterior commissure of rats is also larger in males than in females. The sizes of the two commissures were positively correlated in both sexes, but significantly more so in females than in males. The anterior commissure size difference in rats reported here is opposite in direction from that reported elsewhere for humans, and we speculate that this may derive from differences in the relative proportions of the constituent fibers that make up the anterior commissure in the two species.

Laparoscopic cholecystectomy in a patient with mitochondrial myopathy.

The authors report a 27-year-old woman with mitochondrial myopathy and respiratory failure requiring nasal-CPAP administration who successfully underwent laparoscopic cholecystectomy for chronic cholecystitis. The hypothesis that minimally invasive surgery results in less operative stress is truly substantiated by the experience with laparoscopy in such patients with high risk of perioperative and postoperative complications.

Transabdominal preperitoneal laparoscopic inguinal herniorrhaphy (TPLIH) under regional anaesthesia.

BACKGROUND: In an attempt to investigate whether laparoscopy really is a major advance in the treatment of inguinal hernia, the authors performed laparoscopic transabdominal preperitoneal inguinal herniorrhaphy under regional anaesthesia in 15 consecutive patients, 7 of whom with severe medical conditions contraindicating general anaesthesia. METHODS: In the first 5 patients (Group 1) an epidural anaesthesia was performed, whereas in the following 10 patients (Group 2), fentanyl was added to the epidural anaesthesia, and bupivacaine was administered into the subarachnoid space. RESULTS: Results from Group 1 were poorer than those obtained in Group 2. All patients complained of shoulder pain and discomfort which required the intraoperative administration of analgesics in 7 patients and conversion to open repair in one patient. CONCLUSIONS: Although laparoscopy is a feasible and effective procedure in repairing inguinal hernias, it is not indicated in high-risk patients who can be safely, effectively, and less expensively treated with open tension-free repair techniques under local anaesthesia.

[New studies on population of the North American colonies from the seventeenth to the nineteenth century and some reflections on migration in the modern age]. / Nuovi studi sul popolamento delle colonie nordamericane nei secoli XVII-XIX e qualche riflessione sulle migrazioni in eta moderna.

"In recent years, many authors worked on modern era population movements between 1492 and 1870. American scholars stressed that the settlement of the North American colonies, during [the] 17th and 18th centuries, should be considered a form of migration and should be analysed with the same tools used for the study of the great migration of the 19th century. Instead European scholars tried to pinpoint when 'old regime' migrations developed into the 'great migration'.... This review aims at presenting the most important European and American publications on this topic and points to the subjects to be developed." (SUMMARY IN ENG AND FRE)

Effect of a tracheostomy speaking valve on secretions, arterial oxygenation, and olfaction: a quantitative evaluation.

Tracheostomy speaking valves consist of a one-way valve that closes upon exhalation, causing a redirection of exhaled gas into the upper airway, thus allowing for the primary benefit of speech. The present study was undertaken to test various hypotheses concerning the secondary benefits of speaking valves. We hypothesized that use of a speaking valve will result in a decrease in accumulated secretions, an increase in arterial oxygenation and an improvement in olfactory function. A total of 8 tracheotomized patients met the following inclusion criteria: age > 18; ability to tolerate wearing a speaking valve for at least 3 hours; no unstable medical conditions; no use of thrombolytic agents. While using the speaking valve patients accumulated fewer secretions (74.3 +/- 63.6 vs. 122.8 +/- 44.6 ml/day, p = 0.004, n = 7) and had improved olfactory function (accuracy = 28.4 +/- 5.2 vs 8.1 +/- 2.9%, p = 0.02; and percent correct = 64.2 +/- 2.6 vs 50.0 +/- 3.9%, p = 0.03, n = 6) than when off the speaking valve. No significant differences were found in 24-hour arterial oxygen saturation (pulse oximetry and ABG analysis respectively, n = 7), arterial PO2, pH, PCO2, HCO3, or 24-hour heart rate (n = 7). Thus, the present study found a significant decrease in secretions and improvements in olfaction when tracheotomized patients wore a speaking valve, but no difference in arterial oxygenation.

[Effects of betamethasone on neuromuscular blockade induced by vecuronium in continuous infusion]. / Effetti del betametasone sul blocco neuromuscolare indotto con vecuronium in infusione continua.

The aim of the study was to determine a possible interaction between a corticosteroid (betamethasone) and vecuronium, a nondepolarizing muscle relaxant. The authors studied 20 patients, ASA I-II, aged 20-54, both sexes, scheduled for abdominal surgery. Mechanomyographic and clinical evaluation by single twitch and TOF stimulation of the ulnar nerve at the wrist and measurement of the concomitant abductor pollicis muscle was applied. The onset time of vecuronium after a single bolus dose of 0.08 mg/kg, duration of action to 10% single twitch recovery, duration of continuous infusion of 0.4-0.5 micrograms/kg/min of vecuronium started at 10% single twitch recovery, and the effects of 0.1 mg/kg betamethasone administration 10 min after continuous infusion were evaluated. The recovery rate of vecuronium after stopping infusion at 10% recovery was also evaluated. Corticosteroids may interact with non-depolarizing muscle relaxants both in prejunctional and postjunctional acetylcholine receptors by several mechanisms of action.

[Short-term and long-term surgical prophylaxis with pefloxacin]. / Short-term e long-term profilassi chirurgica con pefloxacina.

In the present study the efficacy and safety of pefloxacin (400 mg/5 ml vial) intravenously administrated for surgical prophylaxis was assessed. Nine hundred and fifty-two patients were treated (599 M, 343 F), with a mean age of 57.9 years +/- 18.6 SD, and in all cases surgical prophylaxis was carried out according to the following scheme: short-term with 2 vials (800 mg) 1 h before the operation, repeated at 12 and 24 hours after the operation; long-term 2 vials (800 mg) 1 h before the operation repeated at 12 and 24 hours after the operation and followed by 1 vial every 12 h for other 2 days. The choice between the two schemes was conditioned by the type of operation and by the basic conditions of the patient. Pefloxacin was seen to be effective in preventing the onset of post-surgical infections (97%), also maintaining the clinical parameters considered within normal limits. Safety was also highly satisfactory, since only 22 (2.3%) cases of side effects occurred, particularly involving the gastro-intestinal system. Thus, in conclusion, the validity of pefloxacin in surgical prophylaxis, with special emphasis on its efficacy in elderly and compromised patients is asserted.

[Myorelaxants and intracranial pressure (ICP) in neurosurgery. Preliminary clinical results of pipecurium bromide (Arduan) on ICP and on cerebral perfusion pressure (CPP)]. / Miorilassanti e pressione intracranica (PIC) in neurochirurgia. Risultati clinici preliminari del bromuro di pipecurium (Arduan) sulla PIC e sulla pressione di perfusione cerebrale (PPC).

Pipecurium bromide, a new non-depolarizing myorelaxant, was administered intravenously, at a dose of 0.06 mg/kg, to 10 patients suffering from expansive endocranial lesions, who had been anesthetised to undergo neurosurgery. The following parameters were recorded simultaneously, before and after drug administration: intracranial pressure, mean arterial blood pressure, central venous pressure, heart rate and end tidal CO2. No statistically significant changes in the above parameters were observed following the administration of the myorelaxant; these observations, which were considered together with the long duration of action, confirm that pipecurium bromide is a valuable tool in anesthesia for neurosurgery.

Clinical evaluation of different doses of pipecuronium bromide during nitrous-oxide-fentanyl anaesthesia in adult surgical patients.

The neuromuscular and cardiovascular effects of three different doses of pipecuronium were studied in 60 adult patients. Neuromuscular blockade was measured using electromyographic activity of the adductor pollicis muscle after supramaximal stimulation of the ulnar nerve at 0.1 Hz and 2 Hz. Three subgroups (A, B, C) of 20 patients received pipecuronium doses of 60, 80 and 100 micrograms kg-1, respectively, as an intubating dose and, when necessary, maintenance doses were administered at 25% single twitch recovery in a dose of one-quarter of the initial one. The onset time was 5.4 +/- 2.0 min for 60 micrograms kg-1 and similar for 80 and 100 micrograms kg-1 (3.9 +/- 1.1 and 3.6 +/- 1.1 min). The duration of action was 45 +/- 10 min for 60 micrograms kg-1, 74 +/- 25 and 94 +/- 21 for 80 and 100 micrograms kg-1, respectively. The recovery indices were measured in all patients after neostigmine administration (Groups B and C) and after neostigmine and edrophonium (Subgroup A, 10 patients each). TOF ratio was significant only 2 min after edrophonium administration in Group A patients. Variations of heart rate and blood pressure were not significant.

Ethnic differences in parenting children in fearful situations.

Administered Zabin and Melamed's (1980) Child Development Questionnaire in their native languages to 20 Haitian, 20 Hispanic, 20 black American, and 20 white American mothers in a public hospital setting to inquire how they dealt with their children in various fearful situations. The white Americans were significantly more likely than black Americans or Haitians to report use of modeling and reassurance, whereas Haitians were less likely than the other groups to report use of these methods. Conversely, the Haitians were more likely than some of the other groups to report use of force in these situations. There were no significant differences in the groups' reported use of positive reinforcement or in reinforcement of dependency once two culturally inappropriate items were removed. The reported differences, especially those involving Haitians, were interpreted as reflecting historical and cultural trends.

The effects of pipecuronium bromide on intracranial pressure and cerebral perfusion pressure.

Twenty patients with expansive pathologic intracranial lesions, who were anesthetized with thiopental, nitrous oxide in oxygen, and fentanyl and mechanically ventilated to ensure normocarbia, received pipecuronium bromide 70 microg/kg i.v. Intracranial pressure (ICP), heart rate, arterial pressure, central venous pressure (CVP), EKG, and end-tidal CO2 were simultaneously recorded for 5 min before and for 15 min after administration of the muscle relaxant. No statistically significant changes in ICP and cerebral perfusion pressure were observed after administration of pipecuronium bromide. Cardiovascular stability was maintained during the study period except for a small, although significant, decrease of the CVP from 5.7 +/- 2.5 (SEM) to 5.0 +/- 2.5 mm Hg. These results, together with the long-lasting muscular effect of pipecuronium bromide, suggest that this new neuromuscular blocking agent may be used for muscle relaxation during neurosurgical operations in patients who have normal intracranial pressure at the time of administration of the drug.

[Diazepam versus midazolam for "wakeful sedation" in oral surgery]. / Diazepam versus midazolam nella "sedazione vigile" in chirurgia orale.

I.v. midazolam was compared with diazepam in 112 dental outpatients in order to obtain a control of sedation. Midazolam has shown better results in all the parameters evaluated (memory scale, pharmacokinetics and pharmacodynamics values) and in controlling sedation. The Authors consider midazolam as a preferred drug in dental outpatients and hope to get it available also in Italy.