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E Morsiani

Publications and source records attributed to E Morsiani.

63 records · Page 4Linked to original sources
PubMedDate not supplied

[Acute and fulminant liver failure: experimental models].

Fulminant hepatic failure (FHF) is a complex clinical syndrome, with an invariably high mortality rate, that follows many possible and different infectious, pharmacologic and surgical liver injuries. The appearance of the syndrome is similar whatever the etiology, but the mechanisms which lead to the development of FHF are greatly varied. In order to understand the possible pathways which drive to FHF, experimental animal models have been used for a long time. Six requirements should be fulfilled by any FHF animal model: 1) reversibility; 2) reproducibility; 3) death from liver failure; 4) the presence of a therapeutic window; 5) the need of large laboratory animal; 6) minimal hazard to personnel involved in the study. In the present paper a number of models are reported and described, and advantages and disadvantages are discussed. It is concluded that with respect to the aforementioned criteria, no available experimental model is yet as satisfactory as expected.

Animals↗
PubMedDate not supplied

[Hybrid (bioartificial) systems for liver support. History and current developments].

Attempts to develop liver support systems for the treatment of acute liver failure patients have ranged in the past, from the use of hemodialysis, or plasma exchange, or activated charcoal particles and synthetic resins, as well as the use of bioreactors loaded with liver tissue. However, no system demonstrated a significant improvement of patient survival, nor has achieved a wide clinical use. Liver transplantation remains the only treatment for severe hepatic failure that can improve patient survival. On the other hands, the chronic scarcity of organs for transplantation, leads to an urgent necessity of liver support systems. In this paper, we reviewed the historical experience and current status of artificial liver support systems, with particular emphasis on the so-called hybrid or bioartificial liver, in which to the traditional artificial components, such as selective membranes, charcoal particles and resins, isolated hepatocytes are used.

Animals↗
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[Isolated hepatocytes and their potential therapeutic use].

Isolated hepatocytes in culture represent an idoneous system for the study of liver physiology and metabolism. Furthermore, they are also widely utilized in pharmacological and toxicological study, in evaluating xenobiotic substance effects on the liver. In this paper, we reviewed the enzymatic methods for liver cell isolation in some mammalian species, as well as the techniques for qualitative and quantitative evaluation of cell number, vitality, purity, morphology and function. Recently, there has been a renewed interest in hepatocyte transplantation and hepatocyte-based liver support systems. From a clinical point of view, isolated hepatocytes could be useful in temporarily substituting an acutely damaged liver, a liver affected by a chronic pathology, or to correct an inherited liver disease carrying a severe metabolic derangement. Early experimental results of allogeneic hepatocyte transplantation, as well as the first clinical trials of bioartificial liver support systems employing xenogeneic hepatocytes are promising and contribute to maintain that interest in liver cell isolation and purification methods.

Animals↗
PubMedDate not supplied

[In vitro experimentation of a new model of radial flow bioreactor containing isolated hepatocytes].

Hepatocyte based artificial liver support systems are under investigation to support acute liver failure patients. The main purpose of such systems is to serve as a bridge to liver transplantation, or to promote spontaneous liver recovery. Limitation in mass-transfer capacity makes hollow-fiber bioreactors unsuited for long-term functioning of hybrid devices. We developed a novel radial-flow bioreactor in which the fluid perfuses the module from the center to the periphery, after having diffused through a space occupied by a three-dimensional structure filled with the hepatocytes. Five grams of freshly isolated porcine hepatocytes were seeded into uncoated, woven-non woven, hydrophilic polyester fabric, overlaid by two polyethersulfone membranes. Liver cells were perfused with 37 degrees C-warm, oxygenated, serum-free tissue culture medium, in which NH4Cl and Lidocaine were added at the final concentration of 1 mM and 60 micrograms/ml, respectively. Ammonium chloride removal, urea synthesis, monoethylglycinexylide (MEGX), pO2, pCO2, and pH were measured throughout the 14 day duration of the study. In a separate set of experiments, a scaled-up version of the radial flow bioreactor containing 150 grams of cells was perfused for 7 h with recirculating human plasma and MEGX production was monitored. During the 2 weeks of the study, an increasing production of urea was paralleled by constant ammonium removal. MEGX concentration after Lidocaine addition increased throughout the 14 days of perfusion with tissue culture medium, as well as after 7 hour perfusion with human plasma. Under transmission and scanning electron microscopy cells appeared attached to the polyester and one to each other, displaying ultrastructural features typical of functioning hepatocytes. Our study showed that liver cells were metabolically active when perfused into the radial-flow bioreactor. This configuration allowed close contact between media, or plasma, and cells at a physiological flow rate, by equalizing the concentration of the perfusing components, including O2, throughout the module. Our results suggest a potential use of this system for temporary extracorporeal liver support in acute hepatic failure patients.

Animals↗
PubMedDate not supplied

[Evaluation of prognostic parameters in colorectal carcinoma. I. Histopathological variability].

A careful histopathological analysis was performed on a series of 244 unselected surgically removed primary colonic and rectal cancers. Tumours were staged according to the TNM system. Tumour type (adenocarcinoma or mucinous carcinoma), grade of differentiation, character of invasive margin, degree of peritumoural lymphocytic infiltration, venous and neural invasion were found to be correlated with the clinico-pathological stage and in some ways interrelated. As a whole our results seem to suggest that histological evaluation of the variables examined may provide information of clinical relevance in the management of patients with large bowel cancer.

Adenocarcinoma↗
PubMedDate not supplied

[Traumatic duodenal lesions].

The authors refer their experience about five cases of traumatic duodenal lesions. They confirm the casual relationship between delayed diagnosis, often due to inaccurate clinical-radiological evaluation, and prognosis. They emphasize the opportunity to perform a simple suture and decompression by nasogastric tube, to selected cases.

Duodenum↗
PubMedDate not supplied

Automated liver cell processing facilitates large scale isolation and purification of porcine hepatocytes.

An automated method for large scale isolation and purification of porcine hepatocytes is described. Liver cells were harvested by a two-step portal vein perfusion with ethylenediaminetetraacetate and collagenase. Hepatocyte purification was carried out using either a standard manual processing method (Procedure A) or an automated processing method using a filtration chamber and a programmable cell washer (Procedure B). Both methods produced high cell yields (Procedure A: 1.30 +/- 0.55 x 10(10) viable hepatocytes/liver; Procedure B: 1.38 +/- 0.32 x 10(10) viable hepatocytes/liver) and viability (Procedure A: 89 +/- 6.5%; Procedure B: 92 +/- 3.9%). Hepatocyte purity was significantly greater after Procedure B than after Procedure A (93.1 +/- 3.1% versus 83.1 +/- 3%, p < 0.01). Isolated hepatocytes by either method were morphologically intact, as demonstrated by transmission electron microscopy showing integrity of plasma membranes and intracellular organelles. Cultured hepatocytes isolated by either method were functionally intact, although those isolated by Procedure A showed significantly lower activity of microsomal 7-ethoxycoumarin-O-deethylase activity (p < 0.05) and mitochondrial succinate dehydrogenase activity (p < 0.01). In conclusion, use of the automated hepatocyte processing method resulted in efficient large scale preparation of porcine hepatocytes, with higher purity and greater retention of differentiated liver metabolic functions, and was found to be less time consuming and less labor intensive.

7-Alkoxycoumarin O-Dealkylase↗