Neurophysiological investigations of hepatic encephalopathy: ISHEN practice guidelines

By studying neuronal activity through neuronal electrogenesis, neurophysiological investigations provide a functional assessment of the nervous system and, therefore, has been used for quantitative assessment and follow‐up of hepatic encephalopathy (HE). The different clinical neurophysiological approaches can be classified depending on the function to explore and their sensitivity to HE. The reliable techniques are those that reflect cortical function, i.e., cognitive‐evoked potentials (EPs) (P300 paradigm), electroencephalogram (EEG), visual EPs (latency>100 ms) and somatosensory EPs (SEPs) (latency between 25 and 100 ms). Short‐latency EPs (brainstem acoustic EPs, SEPs of a latency<25 ms) are in principle insensitive to HE, but can disclose brainstem conduction deficits due to oedema. SEPs and motor EPs can disclose myelopathies. Because of its parallelism to the clinical examination, clinical neurophysiology can complement the neurological examination: (i) to provide evidence of HE in patients who have normal consciousness; (ii) to rule out, at least under some conditions, disturbances of consciousness due to other causes (e.g. drug‐induced disturbances, non‐convulsive status epilepticus) with the reservation that the mildest degrees of encephalopathy might be associated with an EEG pattern similar to that induced by drugs; and (iii) to demonstrate the worsening or, conversely improvement, of HE in the follow‐up period.     

Particulate PAHs in two urban areas of Southern Italy: Impact of the sources, meteorological and background conditions on air quality

The present work studied how much the meteorological parameters and the emission sources can influence the particulate polycyclic aromatic hydrocarbons (Invalid Journal Information PAHs) concentrations in two areas located in Southern Italy (Bari and Taranto). It was found that when the vehicular traffic is the main source of PAHs, there is a negative correlation between ambient temperature, wind speed and PAHs concentration (Bari). This is because these parameters are generally correlated with the dispersion capacity of the atmosphere. In the presence of a large industrial area, the wind direction becomes an important parameter able to determinate large changes in PAHs concentrations. This happened in Taranto where PAHs concentrations are exceptionally high. During the study the seasonal trend of particulate PAHs and PM10 was compared. PM10 did not show a significant seasonal cycle during the year because it is conditioned from a high regional aerosol background, especially during the summertime. On the contrary, particulate PAHs exerted distinct seasonal variation with higher concentrations in the winter and lower concentration during other months of the year. This evidence suggested that PAHs concentrations can be considered a more reliable index for air-quality assessment. In order to identify an index that considers the contributions of other particulate PAHs, it is necessary to calculate the carcinogenic potency of total PAHs (i.e., total BaPeq) obtained by the sum of the benzo[a]pyrene equivalent concentration (BaPeq) for each PAH.     

Functional and morphological effects of defibrotide on renal ischemia

Defibrotide (Df) has been reported to protect various organs from ischemic damage. The aim of this study was to evaluate the effect of Df on renal function and morphology after warm kidney ischemia. Divided into two groups, 14 pigs underwent bilateral renal clamping for 90 min. One group (7 pigs) was treated with Df (32 mg/kg per h) for 6 h, whereas the control group received 5000 IU of heparin. Serum levels of blood urea nitrogen (BUN) and creatinine measured for 6 days were significantly higher in the control group (peak 26.8±16.7 vs 11.0±2.9 mmol/l and 501.2±351.4 vs 230.2±68.0 μmol/lP<0.05). Renal biopsy evidenced a lesser extent of tubular and endothelial damage in Df-treated animals. In conclusion, Df provided relevant protection against renal ischemic injury.     

Selected treatments for duodenal perforation after ERCP. A report of three cases

Perforation is one of the most serious complications of endoscopic sphincterotomy. In the last decade, the management has shifted towards a more selective approach. Three cases are reported here involving three different treatments. In one case, the patient was submitted to a surgical procedure, while a conservative strategy was preferred in the other two, consisting in a naso-biliary drain and endoscopic clip placement, respectively. In this way, the safety of surgical and nonsurgical management of ERCP-related duodenal perforations was tested.     

Nutritional antioxidants as antidegenerative agents

In this study, primary cultures of cerebellar granule neurons were prepared from eight-day-old Wistar rats, and maintained in an appropriate medium containing a high (25 mM) concentration of KCl. All experiments were performed with fully differentiated neurons (eight days). To induce apoptosis, culture medium was replaced with a serum-free medium (containing 5 mM KCl) eight days after plating. In another series of experiments, apoptosis was induced by application of glutamate (50 microM) to the cell cultures. Apoptosis was measured by flow cytometry, the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-fluorescein nick end-labeling) method, and by the classical method of DNA fragmentation. Since there is evidence that an increased formation of reactive oxygen species (ROS) is involved in the apoptosis induced by both low K(+) concentrations and glutamate, a series of natural antioxidants and a red wine lyophilized extract (which is rich in antioxidant compounds) were tested in our experimental model. It was found that ascorbic acid (30 microM) and a red wine lyophilized extract (5 microgram/ml) were capable of blocking the apoptotic process. Addition of the following natural antioxidants did not have any protective effect on apoptosis induced by low K(+) concentrations: trans- and cis-resveratrol (5-200 microM), alpha-tocopherol (100-200 microM), reduced glutathione (100-400 microM), 3-hydroxytirosol (25-100 microM), epicatechin (25-100 microM), or quercetin (25-50 miroM). It is concluded that only a limited number of natural antioxidants are provided with antiapoptotic activity in cultured cerebellar granule neurons. This effect is probably exerted by reducing ROS formation, and by blocking caspase-3 activity.