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Ge/SiGe heterostructures are promising in the view of silicon-foundry compatible THz optoelectronic applications. Here we present a structural and optical characterization of Ge/SiGe parabolic quantum wells that represent ideal systems for room-temperature THz emission and strong light-matter coupling investigation.

Dent’s disease (DD) involves nephrocalcinosis, urolithiasis, hypercalciuria, LMW proteinuria, and renal failure in various combinations. Males are affected. It is caused by mutations in the chloride channel CLCN5 gene. It has been suggested that DD is underdiagnosed, occurring in less overt forms, apparently without family history. A possible approach to this problem is to search for CLCN5 mutations in patients who may have a high prevalence of mutations: end-stage renal disease (ESRD) patients with previous calcium, struvite, or radio-opaque (CSR) stones. We looked for CLCN5 mutations in 25 males with ESRD–CSR stones selected from all of the patients (1,901 individuals, of which 1,179 were males) of 15 dialysis units in the Veneto region. One DD patient had a new DD mutation (1070 G>T) in exon 7. The new polymorphism IVS11–67 C>T was detected in intron 11 in one patient and one control. We also found 28 females with ESRD and stone history, and seven more males with ESRD and non-CSR stones. The prevalence of stone formers among dialysis patients in our region was 3.2%, much lower than the prevalence observed in older studies. Struvite stones continue to play a major role in causing stone-associated ESRD .

We compared the efficacy and safety of apheresisand reinfusion of concentrated ascites (ARCA) versustotal paracentesis plus intravenous albumin (PARA) in aprospective trial on cirrhotic patients with tense ascites. Twenty-four patients wererandomized to either ARCA (N = 12) or PARA (N = 12), andfollowed for two years. Sex, age, Child's class, andrenal and liver function were similar in the two groups. The times of the procedures were 2.7 ±1.0 (ARCA) vs 2.2 ± 1.1 (PARA) hr, with removalof 8.8 ± 3.5 (ARCA) and 6.9 ± 3.4 (PARA)liters of ascites and intravenous infusion of 59.8± 35.2 (ARCA) and 42.5 ± 20.5 (PARA) g of albumin. Both procedures were safe.Biochemical signs of coagulative disturbances having noclinical relevance were observed after ARCA, with anincrease in prothrombin time (P = 0.005) and serum FSP (P = 0.02). No significant changes in renalfunction, serum albumin, or plasma and urinaryelectrolytes were shown. Plasma renin activity increasedafter PARA (P = 0.02) and plasma atrial natriureticfactor increased after ARCA (P = 0.008), although nodifferences were observed in diuresis in the immediatefollow-up. During the long-term follow-up, patientsurvival and recurrence of tense ascites were the same in both groups. We conclude that apheresis andreinfusion of concentrated ascites are as safe andeffective as total paracentesis with albumin infusionfor the treatment of tense ascites in cirrhoticpatients.

Background The Perforin-Granzyme B and Fas/Fas Ligand apoptotic mechanisms are involved in the development of acute renal rejection (AR). We describe our experience of analyzing the expression of cytotoxic T-lymphotoxins (CTL) in biopsies and peripheral blood leukocytes (PBL) for the diagnosis of AR. Methods We analyzed Perforin (P), Granzyme B (GB) and Fas Ligand (FL) expression in 68 renal biopsies and 64 PBL using comparative kinetic RT-PCR and, for GAPDH and FL, we also replicated with real-time RT-PCR. The levels of expression were measured in different groups, such as T0 (biopsies before reperfusion and PBL in recipient before the transplant [Tx]), Td (biopsies and PBL collected for clinical purposes) and Tp (biopsies and PBL two months after Tx). Results A higher CTL expression was seen in non-rejecting (NR) biopsies in the first 2 months after Tx. P and FL were significantly more expressed during AR in all biopsies and in Td, while P remained upregulated in Tp. In PBL, there was no significant increase in CTL transcription during AR. A variable expression of CTL emerged in all T0 biopsies. Conclusions Two lytic pathways are activated in biopsies when AR occurs shortly after Tx, whereas the P/GB mechanism prevails if it occurs later on. Only P and FL in biopsies might be able to predict AR diagnosis, but with a considerable variability in each sample, possibly due to the small portion of tissue core, which may be inadequate for molecular diagnosis. CTL expression in PBL does not correlate with histological AR.

Background Up to 15% of liver transplant candidates have asymptomatic coronary artery diseases, which increase the risk of cardiac complications during and after transplantation. The aim of this study was to prospectively investigate the usefulness of an integrated cardiological approach in cirrhotic patients undergoing liver transplantation. Methods Twenty-four consecutive patients undergoing evaluation for liver transplantation were studied by assessing risk factors for coronary artery diseases, electrocardiogram with QTc interval determination, chest X-ray, echocardiography, 24-hour Holter monitor, myocardial perfusion scintigraphy 99mTcMIBI-GSPECT at rest and after dipyridamole infusion. Cardiac 123I-metaiodobenzylguanidine (MIBG) scan and coronarography were performed in patients with myocardial perfusion defects. Twenty three of 24 patients underwent successful liver transplantation; one patient died on the waiting list. Results Before liver transplantation, 29% of patients were diabetic and 41% were smokers. Eleven of 24 patients had a prolonged QTc interval, and 3/24 had positive myocardioscintigraphy after dipyridamole infusion: in two coronarography was negative, while the 123I-MIBG washout was altered. No cardiac events were recorded during the short-and long-term follow-up after surgery. Conclusions Predictive value of positive cardiac 99mTcMIBI-GSPECT in patients with liver cirrhosis is low, and this may be due to alterations of cardiac microvascular tone as showed by cardiac 123I-MIBG scan.

OLT is an effective therapeutic option for end-stage liver disease and survival rates are encouraging. Disagreement however exists as to whether OLT should be provided to patients with alcoholic cirrhosis. The aim of the study was to evaluate long-term results (recidivism to alcohol consumption, incidence of acute rejection, survival) in patients transplanted for ALD.

It has recently been described that kappa-opioid receptor agonists inhibit antidiuretic hormone secretion and promote water excretion in humans and experimental animals. The aim of this study was to evaluate the aquaretic efficacy of the kappa-opioid receptor agonist RU 51599 in conscious cirrhotic rats with ascites and water retention.In protocol 1, arterial pressure, heart rate, and renal water metabolism were measured in basal conditions and then were measured for 120 minutes after the administration of Ringer's solution (n = 8; 0.4 mL) or RU 51599 (n = 7; 1 mg/kg). In protocol 2, plasma antidiuretic hormone concentration was measured (n = 6) before and 60 minutes after administration of RU 51599 (1 mg/kg). In protocol 3, the effect of RU 51599 (n = 9; 1 mg/kg) was compared with that of the V2-receptor antagonist SKF 100398 (n = 9; 30 micrograms/kg).RU 51599 administration induced a profound diuretic and aquaretic effect without altering arterial pressure and heart rate. In protocol 2, the kappa-opioid agonist reduced by about 50% plasma antidiuretic hormone levels (from 6.6 +/- 0.9 to 3.4 +/- 0.6 pg/mL; P0.05). Finally, the improvement in renal water metabolism induced by RU 51599 was similar to that produced by the V2-receptor antagonist.RU 51599 has a potent aquaretic effect in cirrhotic rats with water retention, suggesting that kappa-opioid receptor agonists may be useful for the treatment of water retention and dilutional hyponatremia in cirrhosis.

We measured the plasma levels of atrial natriuretic factor (ANF) during orthotopic liver transplantation (OLT) in eight adult patients with cirrhosis and ascites. The aim of this study was to determine whether significant differences in ANF concentration may be detected during the individual phases of OLT and to correlate these changes with hemodynamics. In each patient a hemodynamic assessment was achieved using a Swan-Ganz fiber optic catheter for continuous monitoring of cardiac output (CO), systemic vascular resistance index (SVRI), right filling pressure as assessed by central venous pressure (CVP), and left filling pressure by means of pulmonary arterial wedge pressure (PAWP). During reperfusion a clear-cut increase in ANF values was observed (P