Nicola Dioguardi

Hepatocellular carcinoma in Italian patients with cirrhosis.

BACKGROUND AND METHODS Patients with cirrhosis of the liver are recognized as being at risk for hepatocellular carcinoma. The magnitude of the risk, the natural history of this disease, and the possibilities for detecting potentially curable tumors in patients in the Western world are unknown. To address these questions, we examined 447 Italian patients with well-compensated cirrhosis (which was of viral origin in 62 percent of them) from 1985 through 1990, performing serum alpha-fetoprotein assays and real-time ultrasonography every 3 to 12 months. RESULTS Hepatocellular carcinoma was found in 30 patients (7 percent) at base line and in another 29 patients (7 percent of 417 patients free of tumor at base line) during follow-up periods averaging 33 months (range, 1 to 48). The cumulative hazard of the development of hepatocellular carcinoma during follow-up was higher among patients with persistently elevated serum alpha-fetoprotein levels (12 with tumors among 42 with such levels) than among those with fluctuating levels (11 among 82) or those with consistently normal levels (6 among 255). Only 17 patients had potentially operable tumors. The proportion of potentially operable tumors among those detected during follow-up was significantly lower than the proportion at enrollment (4 of 29 vs. 13 of 30, P = 0.027). The survival at one year of the 12 patients who underwent surgery was 67 percent, and the tumor-recurrence rate was 60 percent. Outcome was not appreciably different for the five patients who refused surgery. CONCLUSIONS In the West, as in Asia, patients with cirrhosis of the liver are at substantial risk for hepatocellular carcinoma, with a yearly incidence rate of 3 percent. Our screening program did not appreciably increase the rate of detection of potentially curable tumors.

PREVALENCE OF ANTIBODIES TO HEPATITIS C VIRUS IN ITALIAN PATIENTS WITH HEPATOCELLULAR CARCINOMA

A sensitive radioimmunoassay was used to detect antibodies to hepatitis C virus (HCV) in patients with hepatocellular carcinoma and chronic hepatitis. HCV antibodies (anti-HCV) were detected in 86 of 132 patients with hepatocellular carcinoma with no relation to the presence or absence of hepatitis B surface antigen (HBsAg). The prevalence of anti-HCV was also high in patients with diseases thought to predispose to hepatocellular carcinoma, such as non-A, non-B chronic hepatitis and cirrhosis (74%). In HBsAg-negative patients with hepatocellular carcinoma the prevalence of anti-HCV was lower than that in patients with non-A, non-B chronic hepatitis (16% vs 55%); the prevalence of serum antibodies to hepatitis B core antigen (anti-HBc), a marker of hepatitis B virus infection, was 70% and 28%, respectively. In HBsAg-negative patients with hepatocellular carcinoma, anti-HCV and anti-HBc occurred together nearly three times as often as in patients with chronic hepatitis (54% vs 19%). These data indicate that, in Italy, HCV is an important factor associated with hepatocellular carcinoma and non-A, non-B chronic hepatitis.

Fractal dimension as a quantitator of the microvasculature of normal and adenomatous pituitary tissue.

It is well known that angiogenesis is a complex process that accompanies neoplastic growth, but pituitary tumours are less vascularized than normal pituitary glands. Several analytical methods aimed at quantifying the vascular system in two‐dimensional histological sections have been proposed, with very discordant results. In this study we investigated the non‐Euclidean geometrical complexity of the two‐dimensional microvasculature of normal pituitary glands and pituitary adenomas by quantifying the surface fractal dimension that measures its space‐filling property. We found a statistical significant difference between the mean vascular surface fractal dimension estimated in normal versus adenomatous tissues (P = 0.01), normal versus secreting adenomatous tissues (P = 0.0003), and normal versus non‐secreting adenomatous tissues (P = 0.047), whereas the difference between the secreting and non‐secreting adenomatous tissues was not statistically significant. This study provides the first demonstration that fractal dimension is an objective and valid quantitator of the two‐dimensional geometrical complexity of the pituitary gland microvascular network in physiological and pathological states. Further studies are needed to compare the vascular surface fractal dimension estimates in different subtypes of pituitary tumours and correlate them with clinical parameters in order to evaluate whether the distribution pattern of vascular growth is related to a particular state of the pituitary gland.

Atrial natriuretic factor in cirrhotic patients with tense ascites: Effect of large-volume paracentesis

The plasma levels of atrial natriuretic factor in liver cirrhosis can be affected by various factors, such as ascites, renal function, use of diuretics drugs and dietary sodium intake. Moreover, the influence of high intra-abdominal pressure on cardiac atrial natriuretic factor release in patients with tense ascites has not been investigated. The aim of the present study was to evaluate the circulating levels of atrial natriuretic factor and their relationships to plasma renin activity, aldosterone concentration, and urinary sodium excretion in 45 cirrhotic patients divided into 4 groups: (a) cirrhotics without ascites; (b) nonazotemic cirrhotics with ascites; (c) cirrhotics with ascites and functional renal failure; and (d) cirrhotics with ascites taking diuretics. In some patients with tense ascites, atrial natriuretic factor was also measured after rapid abdominal relaxation by large volume paracentesis. Plasma levels of atrial natriuretic factor obtained in 13 healthy control subjects after 5 days on a 40-50 mEq sodium daily intake were 22.8 +/- 3.3 pg/ml. Mean plasma atrial natriuretic factor levels were normal in patients without ascites (35.1 +/- 11.4 pg/ml) and in those with ascites taking diuretics (27 +/- 9.2 pg/ml), but elevated in patients with ascites not taking diuretics (59.6 +/- 12 pg/ml) and in those with ascites and functional renal failure (58.5 +/- 16.6 pg/ml). These data show that plasma atrial natriuretic factor levels are elevated only in cirrhotic patients who are ascitic and not taking diuretics. In these patients atrial natriuretic factor levels were directly correlated with urinary sodium excretion, even though sodium balance was positive. This could be the consequence of the contrasting effects of antinatriuretic factors, as suggested by the inverse relationships between atrial natriuretic factor and urinary sodium on the one hand and plasma renin activity and plasma aldosterone concentration on the other. Twenty-six patients with tense ascites (12 taking diuretics and 14 not) were treated with rapid large-volume paracentesis (6500 +/- 330 ml of ascitic fluid removed in 168 +/- 16 min). At the end of the procedure, plasma atrial natriuretic factor levels had increased in all patients (from 45.5 +/- 10.1 to 100 +/- 17 pg/ml), whereas plasma renin activity and plasma aldosterone concentration had decreased (from 10.3 +/- 1.6 to 7 +/- 1.3 ng/ml/h, and 1160 +/- 197 to 781 +/- 155 pg/ml, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Immunolocalization of Sperm Protein 17 in Human Testis and Ejaculated Spermatozoa

Sperm protein 17 (Sp17) is a highly conserved mammalian protein whose primary function is still poorly understood. Immunohistochemistry (IHC) in the human testis reveals the presence of Sp17 in some spermatocytes and abundantly in spermatids. All spermatogonia, Sertoli cells, and Leydig cells appear to be immunonegative for Sp17, whereas some interstitial cells are immunopositive. IHC recognized two distinct populations (immunopositive or not for Sp17) in the ejaculated spermatozoa. Although it will be necessary to clarify why some ejaculated spermatozoa do not contain Sp17, its distribution suggests that this protein may be associated with some phases of germinal cell differentiation.

The Complex Functions of Mast Cells in Chronic Human Liver Diseases

Mast cells (MCs) are multifunctional effector cells of the immune system. MCs were originally thought to be involved in IgE-associated immediate hypersensitivity and allergic disorders, but it is now known that they contain or elaborate an array of mediators with a multitude of effects on many other cells. A number of studies have found that MCs are involved in various liver diseases. Although still controversial, they seem to be involved in the liver’s fibrotic response to chronic inflammation and parasitic infection. Hepatic fibrosis is the most frequent liver response to toxic, infectious, or metabolic agents. During the establishment of this pathological condition, there is an increase in the components of the basement membrane that leads to continuous basement membrane-like structures being raised within Disse’s space and a decrease in the number of sinusoid endothelial fenestrae. This leads to a complex process called “sinusoidal capillarization.” At the cellular level, liver fibrogenesis is initiated by hepatocyte necrosis, which induces the recruitment of a large number of inflammatory cells, including MCs, which can be considered the primary effectors of the process changing sinusoidal endothelial cells into capillary-type endothelial cells. We review the roles played by MCs in hepatic chronic diseases and describe a biopsy section of hepatic tissue taken from a patient with chronic C virus-related hepatitis showing diffuse sinusoidal capillarization and a high density of MCs. This observation has led us to hypothesize a relationship between these highly specialized cells and sinusoidal capillarization.

Reduced collagenolytic activity of matrix metalloproteinases and development of liver fibrosis in the aging rat

Although moderate fibrosis is a histological hallmark of the aging liver, the molecular mechanisms underlying this phenomenon are little known. Here, we provide a comprehensive description of hepatic collagen expression and metabolism during natural aging in rats. Interstitial collagen accumulated significantly in the oldest animals, mainly in the periportal area (P<0.05, 19- vs. 2-month-old rats). This was ascribed to COL-III protein deposition (P<0.05 vs. 2-month-old rats), rather than COL-I. Conversely, the transcription activity of COL-III gene decreased (P<0.05) during the considered lifespan (2-19-months), whereas COL-I and transforming growth fator-beta1 (TGF-beta1) mRNA content was substantially unchanged. In the aged rats, hepatic matrix metalloproteinases (MMP) activity, (both MMP-1 and MMP-2) dropped significantly (P<0.05), with a concomitant increase of the inactive tissue inhibitor of MMP (TIMP-1)/MMP-1 complex (P<0.05). MMP-2 and TIMP-1 levels were weakly affected. All together, these results suggest that during natural aging, (i) COL III is the protein that accumulates preferentially in the liver; (ii) liver fibrosclerosis is mainly explained by a reduced proteolytic activity of matrix MMP, in which TIMP-1 seems to be a major regulating factor.

Sperm protein 17 is expressed in human nervous system tumours

BackgroundHuman sperm protein 17 (Sp17) is a highly conserved protein that was originally isolated from a rabbit epididymal sperm membrane and testis membrane pellet. It has recently been included in the cancer/testis (CT) antigen family, and shown to be expressed in multiple myeloma and ovarian cancer. We investigated its immunolocalisation in specimens of nervous system (NS) malignancies, in order to establish its usefulness as a target for tumour-vaccine strategies.MethodsThe expression of Sp17 was assessed by means of a standardised immunohistochemical procedure [(mAb/antigen) MF1/Sp17] in formalin-fixed and paraffin embedded surgical specimens of NS malignancies, including 28 neuroectodermal primary tumours (6 astrocytomas, 16 glioblastoma multiforme, 5 oligodendrogliomas, and 1 ependymoma), 25 meningeal tumours, and five peripheral nerve sheath tumours (4 schwannomas, and 1 neurofibroma),.ResultsA number of neuroectodermal (21%) and meningeal tumours (4%) were found heterogeneously immunopositive for Sp17. None of the peripheral nerve sheath tumours was immunopositive for Sp17. The expression pattern was heterogeneous in all of the positive samples, and did not correlate with the degree of malignancy.ConclusionThe frequency of expression and non-uniform cell distribution of Sp17 suggest that it cannot be used as a unique immunotherapeutic target in NS cancer. However, our results do show the immunolocalisation of Sp17 in a proportion of NS tumour cells, but not in their non-pathological counterparts. The emerging complex function of Sp17 makes further studies necessary to clarify the link between it and immunopositive cells.

PERSISTENCE OF CIRCULATING HBsAg/IgM COMPLEXES IN ACUTE VIRAL HEPATITIS, TYPE B: AN EARLY MARKER OF CHRONIC EVOLUTION

Serial serum samples from 110 patients with acute viral hepatitis type B were tested for HBsAg/IgM complexes by a newly developed solid-phase radioimmunoassay. In 102 patients the infection resolved and they recovered from the disease. In these patients, HBsAg/IgM complexes were either absent from the outset of disappeared from serum within four weeks of admission, long before HBsAg had cleared or serum alanine aminotransferase had returned to normal, 8 patients progressed to chronic HBsAg carrier state and chronic liver disease. In these patients, HBsAg/IgM complexes were detectable in the serum on admission, and never disappeared. These results indicate that persistence of circulating complexes containing HBsAg and IgM after the early phase of acute viral hepatitis type B is a predictor of disease chronicity. As early as the fifth week of illness those in whom chronic liver disease developed could be distinguished from those who recovered.

Geometry of human vascular system: Is it an obstacle for quantifying antiangiogenic therapies?

It is now recognized that all human natural and diseased anatomic systems are characterized by irregular shapes and very complex behaviors. In geometrical terms, tumor vascularity (which is the result of a nonlinear dynamic process called angiogenesis) is an archetypal anatomic system that irregularly fills a 3-dimensional Euclidean space. This characteristic, together with the highly variable nature of vessel shapes and surfaces, leads to considerable spatial and temporal heterogeneity in the delivery of oxygen, nutrients, and drugs, and the removal of metabolites. Although these biologic features have been well established, the quantitative analysis of neovascularity in 2-dimensional histologic sections still fails to view its architecture as a non-Euclidean geometrical object, thus allowing errors in visual interpretation and discordant results concerning the same tumor from different laboratories. We discuss here the tumor-induced vascular system as a fractal object, and what changes this new way of observing may bring to the quantification of effective antiangiogenic therapies.