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Microparticles (MPs), small membrane-bound particles originating from different cell types during activation or apoptosis, mediate intercellular communication, exert pro-coagulant activity and affect inflammation and other pathophysiological conditions. Monocyte-derived MPs have undergone little investigation and, to our knowledge, have never been evaluated for their possible autocrine effects. Therefore, we assessed the ability of monocyte-derived MPs to stimulate human monocytes and monocyte-derived macrophages (MDM).MPs were generated from supernatants of human monocytes stimulated by the calcium ionophore A23187 (12 µM), and then characterized. Human monocytes and MDM of healthy donors were isolated by standard procedures. Cells were challenged by MPs or phorbol 12-myristate 13-acetate (PMA, used as standard stimulus), in the absence or presence of PPARγ agonists and antagonists. Superoxide anion production (measured spectrophotometrically), cytokine release (elisa), PPARγ protein expression (immunoblotting) and NF-κB activation (EMSA assay) were evaluated.Monocyte-derived MPs induced, in a concentration-dependent manner, oxygen radical production, cytokine release and NF-κB activation in human monocytes and macrophages, with lower effects than PMA. In both cell types, the PPARγ agonists rosiglitazone and 15-deoxy-Δ(12,14) -prostaglandin J(2) (15d-PGJ(2) ) inhibited MPs-induced stimulation and this inhibition was reversed by a PPARγ antagonist. In human monocyte/macrophages, MPs as well as rosiglitazone and 15d-PGJ(2) induced PPARγ protein expression.In human monocyte/macrophages, monocyte-derived MPs exert an autocrine activation that was modulated by PPARγ ligands, inducing both pro-inflammatory (superoxide anion production, cytokine release and NF-κB activation) and anti-inflammatory (PPARγ expression) effects.

AIM: The use of hepatitis B immunoglobulin (HBIg) combined with nucleos(t)ide analogues (NUCs) has improved outcomes in post-hepatitis B (PHB) liver transplant (LT), reducing the 1-year recurrence rate below 10%. The aim of this study was to evaluate efficacy and pharmacokinetics of prophylaxis with NUC(s) and intravenous (iv-) or intramuscular (im-) HBIg in 33 PHBLTs, transplanted for more than 1 year. METHODS: During the first six months of the study, 18 subjects received 5000 IU of iv-HBIg every four weeks and 15 patients 2160 IU/12 mL of im-HBIg every two weeks. In the following six months, 31 subjects were switched to two different concentrations of im-HBIg, 2160/12 mL (16 patients) or 2000 IU/6 mL every two weeks (15 patients). RESULTS: All patients remained HBsAg-negative and 30/31 maintained anti-HBs >100 IU/L. Overall mean anti-HBs titer during treatment was 363 IU/mL. Mean HBIg half-life was 21.4, 27.3 and 26 days with intravenous, diluted or concentrated im-preparations, respectively. CONCLUSION: These results confirm an analogue efficacy and tolerance of iv- and im-HBIg combined with antivirals in prophylaxis of hepatitis B after LT. Anti-HBs titers three times higher than aimed and four weeks mean half-life could suggest the reduction of doses and the elongation of the interval of administration of im-HBIg.

Background Cirrhotic patients without overt hepatic encephalopathy may have cerebral function alterations called minimal hepatic encephalopathy (MHE). Our goal was to evaluate the role of partial pressure of ammonia (pNH 3 ), neuropsychological, and neurophysiological assessment in detecting cognitive changes in cirrhotic patients awaiting liver transplantation. Materials and Methods Fourteen cirrhotic patients listed for liver transplant were studied. All patients underwent the neuropsychological battery called PSE. Neurophysiological assessment including spectral EEG (sEEG), evoked potential P300 and pNH 3 and venous and arterial ammonia levels was performed in all patients. Four patients were transplanted. Results Liver disease etiology was alcoholic in four patients, viral in six mixed in two, and cryptogenic in two. PSE scores revealed MHE in 8 patients; sEEG was altered in 6, and P300 in 1. No correlations were detected between P300, sEEG, and PSE. pNH 3 and arterial ammonia levels were significantly higher in the subgroup of patients with altered sEEG and were correlated with theta band increase in sEEG but not with pathological PSE scores or P300 wave abnormalities. Conclusions The combination of sEEG and PSE, and possibly also pNH 3 and arterial ammonia, is useful in detecting cerebral function alterations in cirrhotic patients with no apparent encephalopathy, whereas P300 is not. The diagnosis of MHE obtained using the multimodal approach adopted in this study may enable the adequate treatment of these patients prior to surgery, which includes advising them not to drive and adjusting their priority on the waiting list for OLTx in the light of a condition that cannot be evaluated by Child Pugh score and MELD score.