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L'articolo costituisce una "review" del confronto tra le varie posizioni etiche riguardo alla questione dei trapianti d'organo. L'Autore, dopo aver considerato rapidamente gli aspetti legali connessi all'argomento e stigmatizzato la pratica del "commercio" di organi, riflette su temi attinenti ai trapianti - come la corporeità, la morte cerebrale, l'espianto da cadavere - concludendo lo studio con la delineazione dei fondamenti etici alla base del trapianto d'organo.

The HBeAg/anti-HBe system was studied as a marker of infectivity and chronic progressive liver disease in 460 hemodialysis patients. The importance of HBeAg as an index of infectivity was confirmed in that it was present simultaneously with specific DNA polymerase (31 patients) and by the presence of widely diffuse core particles in the hepatocyte nuclei (revealed by biopsy in six patients). In contrast, HBeAg showed no useful correlation with progressive liver disease, the absence of which was confirmed in all cases by biochemical and histological studies.

Die vorliegende Studie befast sich mit einigen funktionellen Aspekten des peripheren Nervensystems, insbesondere mit elektromyographischen Untersuchungen vor und nach Therapie mit Cephacetril bei 15 Patienten, die sich unter Dauerdialyse befinden. Die Patienten litten an verschiedenen interkurrenten Infektionskrankheiten, u. a. akute Bronchitis, Pneumonie, akute Zystitis, postoperative Infektion; die Dosierung von Cephacetril betrug 0,5–1 g/die. Beim genannten Patientengut, das eine problematische funktionelle Stabilitat des peripheren Nervensystems bei Uramie besas, hat sich Cephacetril als vorzuglich anwendbar erwiesen.

2 cases of acute renal failure associated with diclofenac therapy are reported. In the 1st case no other risk factors but diclofenac administration were identified. Renal biopsy showed patchy interstitial infiltration of mononuclear cells and polymorphonuclear leukocytes. In the 2nd case preexisting nephropathy and heart failure were underlying illnesses. In both cases renal function returned to the basal values after stopping the drug.

A case of nonoliguric acute renal failure after treatment with piromidic acid and acetylsalicylic acid is reported. The histological picture of acute interstitial nephritis and a positive leukocyte in

2 cases of acute renal failure associated with diclofenac therapy are reported. In the 1st case no other risk factors but diclofenac administration were identified. Renal biopsy showed patchy interstitial infiltration of mononuclear cells and polymorphonuclear leukocytes. In the 2nd case preexisting nephropathy and heart failure were underlying illnesses. In both cases renal function returned to the basal values after stopping the drug.

The following method is proposed to make the serum concentration of the middle molecules evident and to isolate them: 1) Fractioning of serum by gel filtration with sephadex G 75 columns in order to eliminate proteins and other substances with mol. weight less than 3,000-3,500. 2) Collection of fractions with mol. weight greater than 3,000-3,500 their lyophilisation and their successive gel filtration by sephadex G 15 columns. The concentration of substances in the single fractions is evaluated by ultraviolet light absorption (wave length 254 nm). The peaks of the patterns show a great difference between normals and uremics. The uremic peaks are always higher than normals. The mol. weight the substances in the peaks obtained by gel filtration with sephadex G 75 and G 15 was verified by radiolabelled substances of known mol. weight added before gel filtration. The substances isolated by sephadex G 75 from 10 and 20 cases of uremics and normal controls were diafiltered by Diaflo membrane UM 05 (nominal mol. weight cut - off 500). The diafiltered substances (mol. weight between 500 and 3,500) were investigated. A great difference between uremics and normal controls of dry mol. weight was observed, while the percentage concentration of C, H, N and of amino acids evaluated after acid hydrolysis showed no difference between the two groups. The liberation of amino acids after acid hydrolysis confirmed the presence of peptides among the middle molecules. Middle molecules in the urine of uremic and normal subjects have been investigated by the same method.

In 20 patients with nephrotic syndrome (10 minimal change glomerulonephritis, MCN; 10 focal glomerulosclerosis, FGS) the peripheral blood lymphocytes showed a statistically significant increase in IgG-bearing cells (SIgG-C) in comparison with 30 patients with other histological types of primary glomerulonephritis with and without nephrotic syndrome (14 and 16, respectively). In the same MCN and FGS patients the serum IgG levels were slightly decreased. Furthermore, 5 cases of MCN in sustained remission for 1 year after steroid therapy showed normalization of the SIgG-C and the serum IgG levels. The possible significance of these phenomena in the pathogenesis of the hypo-IgG-globulinemia in MCN and FGS is discussed.

The ultrastructure (US) of the skeletal muscle from 10 patients on conservative treatment (PCT) and 10 haemodialysed patients (HP) was studied. The two groups exhibited no qualitative differences but quantitative alterations of the mitochondrial apparatus and capillary vessels were more impressive in the HP group. Disarray and loss of the myofibrillar sarcoplasm was the most obvious change in the uraemic muscle. The US findings are consistent with a neurogenic atrophy of the uraemic skeletal muscle but other features indicate a primary myopathic damage probably caused by a deficit of muscle microcirculation and by changes in the mitochondrial respiratory chain.

One hundred and one patients were treated for up to two years for three hours every other day (10.5 hr/week), or four hours thrice-weekly with conventional disposable 1m2 dialysers have been investigated. Rigorous control of water balance and the maintenance of predialysis serum K and PO4 within normal limits were the main criteria for judging the adequacy of the treatment. The results regarding blood pressure, phosphate problems, haematocrit, peripheral nerve status, pericarditis and range of rehabilitation are discussed.

The results regarding the treatment of 55 patients, 6 of them treated for, at least 10 months, with 1 sq. meter disposable dialyzers and a dialysis strategy of 3 hours every other day or 4 hours trice weekly have been presented. Clinical indexes especially regarding erythropoiesis and peripheral nerve status will be discussed. Th results show that this new method of treatment is feasible and may become in the future a routine strategy for chronic intermittent dialysis.

The present paper reports some aspects of glycolipid metabolism observed during and after dialysis of varying duration, and the effects of glucose content in dialysis fluid. Some substances used in dialysis interfere with glycolipid metabolism: heparin (Robinson and French, 1960; Wolff and Wolff, 1960); sodium acetate (Bloch, 1947; Ghosal et al, 1969; Mion et al, 1964); and glucose in high (Leonards et al, 1961; Mendelssonhn et al, 1967) or low concentrations (Drukker et al, 1964; Hagstam et al, 1969) or, more recently, completely eliminated (Alwall et al, 1970; Hubner et al, 1971).

Gel filtration through Sephadex (g 75 and 15) and ultrafiltration and diafiltration through selective membrances have been carried out on 172 uremic sera, 89 normal sera, uremic and normal urines and hemodialysis fluid. The accumulation in uremic sera of substances wwith molecular weights between 500 and 3,500 (so called "middle molecules") was demonstrated. Molecular weight evaluation was verified on single effluent fractions using different added isotopes. Evaporation of serum to dry weight revealed a 2-3 fold increase in solids compared to normal values. Estimation of the fractional content of individual elements and quantitative amino acid analysis (before and after acid hydrolysis) did not show any difference between normal and uremic subjects, but there was a significant increase of peptides in uremic serum. The accumulation of peptides was confirmed by high voltage electrophoresis. Urinary excretion of substances with comparable molecular weights to those found in uremic serum was demonstrated, but there was no significant difference between urine from normal and from uremic subjects. A steady state of chronic uremia with high urinary volume is therefore consistent with a normal urinary excretion of middle molecules with increased concentrations in serum and glomerular filtrate. Tubular reabsorption may also be decreased because the urinary excretion of middle molecules increases with the development of tubular proteinuria in patients with pyelonephritis. Dialysis treatment removes moderate amounts of middle molecules; their serum concentration decreases slightly after dialysis and they are detectable in dialysis fluid. The identification, metabolism and biological effects of middle molecules are discussed in relationship to uremic toxicity and the effects of different forms of dialysis treatment.

The clinical and bioptic aspects of 211 cases of primary mesangioproliferative glomerulonephritis with urinary abnormalities lasting mre than 1 year were reviewed. We observed the following clinical syndromes: 1) Persistent proteinuria, isolated or with microhematuria: - a) with latent onset: 39% with hypertension (H); 10% with renal failure (RF); - b) with acute nephritic syndrome at onset: 31% with H; 6% with RF; 2) Recurrent macroscopic hematuria: 26% with H; 10% with RF; 3) Nephrotic syndrome: 70% with H; 29% with RF. The histological lesions, diffuse in all cases, appeared unrelated to the clinical syndromes and/or immunofluorescent patterns. In 65 cases with prevalent mesangial deposits of IgA, 46% showed persistent proteinuria with latent onset, 23% persistent proteinuria with acute nephritic syndrome at onset, 28% recurrent hematuria and 3% nephrotic syndrome. 37% of such patients developed H, 14% RF and 6% remission (R). On the other hand in 65 patients with other deposits the clinical aspects were as follows: persistent proteinuria with latent onset: 46%; persistent proteinuria with acute nephritic syndrome at onset: 31%; recurrent hematuria: 17%; nephrotic syndrome: 6%. 35% of these cases displayed H; 9% RF and 8% R.primary mesangioproliferative glomerulonephritis appears to represent a heterogeneous group with only the morphological aspects in common and associated with one of the three above-mentioned clinical syndromes. Immunohistology shows different Ig and/or complement which bear no specific relationship with clinical courses. In particular IgA deposits are present in 50% of the cases and are only related to higher incidence of recurrent hematuria and abnormal IgA serum levels.

The plasma concentration and urinary excretion after a single 500 mg dose of Aminosidine have been studied in 12 patients with different degrees of renal failure and 4 normal subjects. In normal subjects the plasma half-life is 2.47 hr; in patients with creatinine clearance (Ccr) of 30-60 ml/min, its 6.7 hrs.; in patients with Ccr of 10-30 ml/min, it is 16.7hrs.; in patients with Ccr less than 10 ml/min, it is 36.6 hrs. A dose of 0.5 g of Aminosidine should be given to normal subjects every 12 hr. When renal function is reduced, the interval (in hr) between doses should be the following: Ccr 60-40 ml/min: 19-28;Ccr 40-30 ml/min; 28-35; Ccr 30-20 ml/min: 35-47; Ccr 20-10 ml/min: 47; Ccr less than 10 ml/min: 76.

Filtration through membranes with different nominal cut-off was used for isolation of middle molecule fractions from uremic serum. Comparison was made with test substances which in gel filtration did not show a regular relationship between molecular weight and partition coefficient. The XM50 membrane (cut-off 50,000 D) showed the highest permeability to middle molecules (greater than 84%) whereas CF50 (same cut-off) retained middle molecules to some extent if filtration was carried out only once. The UM05 membrane (cut-off 500 D) was highly permeable for small molecules less than 300 D, intermediary permeable for molecules between 300 and 1000 D and retained molecules between 1,100 and 1,350 D more efficiently. It is concluded that filtration through membranes is a suitable method for identification of middle molecules.

In haemorrhagic rats norepinephrine normalises BP but maintains renal cortical pressures at low levels. Dopamine, however, can normalise both BP and renal cortical pressures. Dopamine is therefore useful in treating haemorrhagic hypotension in addition to or while awaiting blood transfusion. The efferent arteriole in superficial nephrons is a passive resistance in glomerular haemodynamics.