Functional shift with maintained regenerative potential following portal vein ligation

Selective portal vein ligation (PVL) allows the two-stage surgical resection of primarily unresectable liver tumours by generating the atrophy and hypertrophy of portally ligated (LL) and non-ligated lobes (NLL), respectively. To evaluate critically important underlying functional alterations, present study characterised in vitro and vivo liver function in male Wistar rats (n = 106; 210-250 g) before, and 24/48/72/168/336 h after PVL. Lobe weights and volumes by magnetic resonance imaging confirmed the atrophy-hypertrophy complex. Proper expression and localization of key liver transporters (Ntcp, Bsep) and tight junction protein ZO-1 in isolated hepatocytes demonstrated constantly present viable and well-polarised cells in both lobes. In vitro taurocholate and bilirubin transport, as well as in vivo immunohistochemical Ntcp and Mrp2 expressions were bilaterally temporarily diminished, whereas LL and NLL structural acinar changes were divergent. In vivo bile and bilirubin-glucuronide excretion mirrored macroscopic changes, whereas serum bilirubin levels remained unaffected. In vivo functional imaging (indocyanine-green clearance test; (99mTc)-mebrofenin hepatobiliary scintigraphy; confocal laser endomicroscopy) indicated transitionally reduced global liver uptake and -excretion. While LL functional involution was permanent, NLL uptake and excretory functions recovered excessively. Following PVL, functioning cells remain even in LL. Despite extensive bilateral morpho-functional changes, NLL functional increment restores temporary declined transport functions, emphasising liver functional assessment

Expresión del factor de crecimiento del endotelio vascular en carcinomas renales y su relación con la microdensidad vascular, la embolia tumoral y las metástasis a distancia

Los carcinomas renales de células claras derivan de las células epiteliales renales originadas en los túbulos contorneados proximales de las nefronas y se caracterizan por presentar una profusa vascularización. El funcionamiento aberrante del gen del VHL presente en gran parte de estos tumores, se traduce en la liberación de una serie de factores de crecimiento, entre ellos del factor de crecimiento del endotelio vascular (VEGF), implicado en el crecimiento y proliferación de las células tumorales, así como en el proceso de angiogénesis necesaria para el desarrollo de metástasis por vía hematógena. Varios trabajos han sostenido la hipótesis de que la marcación con VEGF podría ser de importancia como factor pronóstico. El objetivo del presente trabajo es determinar la distribución e intensidad de la inmunomarcación con VEGF en tumores renales de células calaras y su relación con la microdensidad vascular (MDV), la presencia de embolias tumorales y las metástasis a distancia.Facultad de Ciencias Médica

Structural Analysis of a Peptide Fragment of Transmembrane Transporter Protein Bilitranslocase

Using a combination of genomic and post-genomic approaches is rapidly altering the number of identified human influx carriers. A transmembrane protein bilitranslocase (TCDB 2.A.65) has long attracted attention because of its function as an organic anion carrier. It has also been identified as a potential membrane transporter for cellular uptake of several drugs and due to its implication in drug uptake, it is extremely important to advance the knowledge about its structure. However, at present, only the primary structure of bilitranslocase is known. In our work, transmembrane subunits of bilitranslocase were predicted by a previously developed chemometrics model and the stability of these polypeptide chains were studied by molecular dynamics (MD) simulation. Furthermore, sodium dodecyl sulfate (SDS) micelles were used as a model of cell membrane and herein we present a high-resolution 3D structure of an 18 amino acid residues long peptide corresponding to the third transmembrane part of bilitranslocase obtained by use of multidimensional NMR spectroscopy. It has been experimentally confirmed that one of the transmembrane segments of bilitranslocase has alpha helical structure with hydrophilic amino acid residues oriented towards one side, thus capable of forming a channel in the membrane

Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

"Valutazioni tecnico-economiche sui possibili usi alternativi del biogas da discarica"

In: Atti del 62° Congresso Nazionale ATI. Salerno, 11-14 Settembre 200

Assessing the impact of micro-generation technologies on local sustainability

The work addresses the role of local energy planning for the introduction of low carbon policies to achieve challenging climate targets. Taking as reference case an urban area that aims to become Sustainable Community, several initiatives have been assessed. Two target years, 2020 and 2050, have been analysed with the aid of EnergyPlan, an integrated energy system model based on the hourly energy demand and supply able to consider constraints deriving from grid stability. The effects of climate change, defined by a regional climate model, have been analysed in the long-term scenario. The work focuses on the impact of a high share of micro-generation technologies for satisfying the energy demand of the building sector, following an original comprehensive approach that helps a better understanding of the implication of such low carbon policy. Both solar devices and micro-combined heat and power systems have been taken into account, the latter covering different technologies (i.e. internal combustion engines, Stirling engines, microturbines and fuel cells). Results show that the use of a high share of micro-generation technologies can help to reduce CO2 emissions and enable an increase in large-scale intermittent renewable production, only if a coordinated local energy plan combined with an optimal operation strategy is pursued. Moreover the work outlines the importance of developing an integrated energy system for introducing such technologies that can help to: (i) decarbonise the building sector, (ii) increase energy security and iii) postpone the investments in new network capacit

Development of renewable energy strategies for small urban areas

The role of municipalities to foster renewable energy generation has been recently recognized and pointed out. First, their involvement comes from the fact that strategic planning at local level is necessary due to the site-specific nature of renewable sources. Second, in the last years the role of citizens has turned out to be a critical issue as demonstrated, for instance, by the NIMBY syndrome, suggesting local governments participation in the process, since they can benefit by a nearer connection to inhabitants. Third, the point of view of local governments, who are the institutional actors more directly involved, can help to better estimate both technical and non-technical barriers for the growth of renewable energy. Starting from the analysis of a small urban area, Corinaldo, located in the Central Italy, whose electricity production from renewable sources is able to cover about 70% of the entire municipal electricity use, the present paper aims at identifying renewable energy strategies for small urban areas that can be suitable for big cities and metropolitan regions as well. First, the main energy strategies carried out by the municipality under study have been identified; second, the main barriers and measures to a much higher renewable energy penetration have been discussed. This analysis has been conducted with the aid of a specific tool, EnergyPlan, developed by the Aalborg University to evaluate energy alternatives based on renewable energy systems. Finally, general findings suitable for fostering renewable energy penetration have been pointed out. In particular results show that the higher percentage of renewable energy on the total energy demand, which generally characterizes small urban areas, mainly derives -other than from the obvious reason related to the area dimension- from the closer connection between the local governance and citizens, able to improve communication and succeed in delivering important messages

Micro-scale LNG liquefaction plants

This paper deals with the liquefaction of natural gas by micro-scale plants. The aim of the paper is to describe the possible applications of such plants, focusing on the exploitation of stranded wells. A technical and economic analysis of different liquefaction technologies is performed and the liquefaction cycles considered are Linde cycle, Claude cycle and reverse-Brayton cycle. Additional considerations on Mixed Refrigerant Cycles and liquefaction by liquid nitrogen vaporization are reported. Moreover an overview on the competitors technologies (Gas-To-Liquid, Gas-To-Hydrate, Compressed Natural Gas and power generation) is presented in order to understand the most suitable for each given application. Final results of the analysis show the guidelines for economic feasibility of micro-scale liquefaction

PERFORMANCE ANALYSIS OF COGENERATIVE AND TRIGENERATIVE PLANT WITH MICROGAS-TURBINE

The paper reports on the performance analysis of cogenerative and trigenerative plants based on Micro Gas Turbines. The core of the system is a natural-gas-fuelled Turbec T100 operating on a regenerated open-air cycle. A code specifically developed by the authors to simulate the micro gas turbine in cogeneration plants, and already checked against experimental data, has been upgraded to simulate the unit’s behavior when facing also a cooling demand (trigenerative case). For this purpose the model of a water-LiBr single-effect absorption chiller driven by hot water has been used. The analysis cover all the unit’s application range and represent a start for its economic evaluation