Lithium-sodium countertransport in erythrocytes of normal and hypertensive subjects. Relationship with age and plasma renin activity.

Lii-Nao countertransport was measured in red blood cells of 58 normotensive subjects (27 females and 31 males), 60 patients with essential hypertension (26 females and 34 males), and in 28 with secondary hypertension (19 females and 9 males). The mean values (+/- SEM) expressed as mmol Li (1 red cells X hr)-1 were 0.18 +/- 0.02 (females) and 0.20 +/- 0.01 (males) in the control group, 0.34 +/- 0.04 (females) and 0.39 +/- 0.03 (males) in essential hypertension, 0.16 +/- 0.03 (females) and 0.19 +/- 0.02 (males) in secondary hypertension. The mean value of Lii-Nao countertransport obtained in essential hypertension was statistically different from those obtained in both normals (p less than 0.001) and patients with secondary hypertension (p less than 0.001). A negative correlation was found between age and Lii-Nao countertransport in normotensive males (r = - 0.648; p less than 0.001) but neither in normal females nor in patients with essential hypertension. A positive correlation (r = + 0.425; p less than 0.05) was found between plasma renin activity after intravenous furosemide and Lii-Nao countertransport in essential hypertension. These findings support the hypothesis of a characteristic cation transport across the red blood cell membrane of patient with essential hypertension which might be correlated with the plasma renin activity.

Relationships of plasminogen activator inhibitor-1 to anthropometry, serum insulin, triglycerides and adipose tissue fatty acids in healthy men.

Increased plasma levels of plasminogen activator inhibitor-1 (PAI-1), responsible for reduced fibrinolytic activity, have been shown to be an important risk factor for cardiovascular disease. PAI-1 plasma levels are influenced by several factors which have not yet been fully clarified, including dietary fat intake. The relationships of PAI-1 with other cardiovascular risk factors are still not well known. In a random sample of 38-year-old healthy men (n = 94), the association of PAI-1 plasma levels (measured as activity and antigen) with anthropometric parameters, serum lipids, fasting and 2 h insulin and glucose concentration after oral glucose-load was analysed. Furthermore, the fatty acid composition of subcutaneous adipose tissue, as an objective and reliable index of dietary fat intake, was measured. The univariate analysis showed that plasma levels of PAI-1 were significantly associated with body mass index (BMI) (r = 0.37, P < 0.001), waist/hip ratio (WHR) (r = 0.26, P < 0.01), serum triglycerides (r = 0.47, P < 0.0001), HDL/total cholesterol ratio (r = -0.35, P < 0.001), fasting and 2-h insulin (r = 0.27, P < 0.01 and r = 0.34, P < 0.001) and glucose concentrations (r = 0.25, P < 0.05 and r = 0.28, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of plasminogen activator inhibitor-1 in human adipose tissue: a role for TNF-alpha?

Elevated plasminogen activator inhibitor-1 (PAI-1) plasma levels, responsible for reduced fibrinolysis, are associated with animal and human obesity and with increased cardiovascular disease. The expression of PAI-1 has been found recently in animal and human adipose tissue. Factors and mechanisms regulating such an expression remain to be elucidated. In omental and/or subcutaneous biopsies from obese non-diabetic patients, incubated in Medium 199, we have confirmed that human adipose tissue expresses PAI-1 protein and mRNA; furthermore we have demonstrated that such an expression is clearly evident also in collagenase isolated human adipocytes and that it is stimulated by incubation itself and enhanced by exogenous human tumor necrosis factor-alpha (h-TNF-alpha). Since human adipose tissue produces TNF-alpha, to further characterize the relationship of PAI-1 to TNF-alpha, human fat biopsies were also incubated with Pentoxifylline (PTX) or Genistein, both known to inhibit endogenous TNF-alpha through different mechanisms. PTX caused a dose-dependent decrease of basal PAI-1 protein release, reaching 80% maximal inhibitory effect at 10(-3)M, the same inhibitory effect caused by Genistein at 100 microg/ml. This was associated to a marked inhibition of PAI-1 mRNA and of endogenous TNF-alpha production. Furthermore, when human fat biopsies were incubated in the presence of polyclonal rabbit neutralizing anti-human TNF-alpha antibody (at a concentration able to inhibit 100 UI/ml human TNF-alpha activity), a modest but significant decrease of the incubation induced expression of PAI-1 mRNA was observed (19.8+/-19.0% decrease, P = 0.04, n = 7). In conclusion, the results of this study demonstrate that PAI-I expression is present in human isolated adipocytes and that it is enhanced in human adipose tissue in vitro by exogenous TNF-alpha. Furthermore our data support the possibility of a main role of endogenous TNF-alpha on human adipose tissue PAI-1 expression. This cytokine, produced by human adipose tissue and causing insulin resistance, may be a link in the clinical relationship between insulin-resistance syndrome and increased PAI-1 plasma levels.

Relationships of blood pressure to fibrinolysis: influence of anthropometry, metabolic profile and behavioural variables.

OBJECTIVE: To investigate the relationship between blood pressure and the plasma fibrinolytic system and to verify whether this association was independent or mediated by one or more potential confounding factor. DESIGN: A random sample of 94 males aged 38 years subdivided into normotensives, hypertensives and those hypertensives with the highest blood pressure values. METHODS: Overall and regional obesity, blood lipids, fasting and 2-h post-load glucose, C-peptide and insulin levels, and main behavioural variables, including adipose tissue fatty acid composition (an objective index of dietary fat intake), were measured. The plasma fibrinolytic system was evaluated by determining activities and total plasma concentrations of both tissue-type plasminogen activator before and after venous occlusion, and its inhibitor plasminogen activator inhibitor type-1 (PAI-1). RESULTS: PAI-1 activity was significantly higher in the hypertensives than in the normotensives. PAI-1 antigen tended to parallel PAI-1 activity, and levels of tissue-type plasminogen activator antigen and activity tended to be lower in the hypertensives at baseline and after venous occlusion, but not significantly different from those in the normotensives. The hypertensives also had significantly higher body mass index and body fat content (measured by bio-impedance), increased plasma triglycerides, uric acid, fasting and 2-h glucose, C-peptide and insulin concentrations. In univariate linear regression analysis both systolic and diastolic blood pressures were found to be positively correlated with PAI-1 levels (r = 0.27, P < 0.01, for both). This correlation was maintained after adjustment for total body fat, fasting glucose, fasting insulin concentration or adipose tissue alpha-linolenic acid; however, it was no longer significant after adjustment for plasma 2-h insulin, 2-h C-peptide, 2-h glucose or triglyceride levels. Multivariate regression analysis revealed that only 2-h insulin and triglyceride concentration showed an independent association with PAI-1 levels. CONCLUSIONS: This study confirms that, in 38-year-old males, hypertension is associated with increased PAI-1 activity. It supports the possibility that the relationship between blood pressure and PAI-1 may reflect the overall effect of the insulin resistance syndrome (in particular hyperinsulinaemia and hypertriglyceridaemia) rather than a direct effect of blood pressure on the fibrinolytic system.

Liver steatosis and its relation to plasma haemostatic factors in apparently healthy men--role of the metabolic syndrome.

The relationship between liver steatosis, evaluated by ultrasonography, and various plasma haemostatic factors was examined in 64 apparently healthy males, aged 38 years. Plasma levels of factor VII clotting activity (F-VIIc), plasminogen activator inhibitor-1 (PAI-1) activity and antigen, tissue-type plasminogen activator (t-PA) activity significantly differed in men with liver steatosis (n = 31) as compared with those without steatosis (n = 33). No significant differences were found in t-PA antigen and F-VII antigen. The men with liver steatosis also had significantly higher body mass index (BMI), plasma triglyceride and 2 h post-load insulin concentrations. While the differences in plasma haemostatic factors were substantially unchanged after adjustment for BMI, they totally disappeared when further allowance was made for plasma triglyceride and 2 h insulin concentrations. In conclusion, these results indicate that liver steatosis correlates specifically with increased PAI-1, F-VIIc and decreased t-PA levels, and suggest that such a relation is largely mediated by concomitant alterations in plasma triglyceride and insulin concentrations.

Specific and non-specific folate binding protein in normal and malignant human tissues.

Binding of tritiated folic acid by supernatants prepared from extracts of normal and leukaemic leucocytes, normal mucosa, and malignant tumours from different parts of the gastrointestinal tract has been measured using Sephadex-gel filtration and albumin-coated charcoal techniques. Non-specific binding (measured by Sephadex G-75 gel filtration) was almost invariably greater than specific binding measured by albumin-coated charcoal separation of bound and unbound folate. In nine normal leucocyte extracts, binding measured by Sephadex G-75 filtration ranged from 1.3 to 18.2 (mean 8.2) pg/mg protein and by albumin-coated charcoal from 1.0 to 14.8 (mean 6.7) pg/mg protein. Raised specific binding was found in the extracts from leucocytes of eight of 14 patients with chronic granulocytic leukaemia, in four substantially so (389, 121, 108, 59.7 pg/mg protein), but was only marginally increased in one of eight cases of acute myeloid leukaemia and in two of five cases of chronic lymphocytic leukaemia. Binding was normal in the extracts of all three cases of acute lymphoblastic leukaemia tested. Among the tissues of the gastrointestinal tract binding was greatest by the duodenal mucosa and liver. Extracts of carcinoma of the stomach and colon bound greater amounts of (3)H-folic acid than the corresponding normal mucosal extracts but the differences were not large. Sephadex G-200 gel chromatography showed more than one binding peak in the extracts of liver and duodenum but only one peak in the other tissues of the gastrointestinal tract, and only one peak, of molecular weight either about 50 000 or over 200 000, in the leucocyte extracts.

Endogenous phosphorylation of membrane proteins in normal and in hereditary spherocytosis erythrocytes.

The phosphorylation state of the proteins in hereditary spherocytosis erythrocyte membranes, incubated in the presence of [gamma-32P]ATP, appears to be different from that in normal ones. This is indicated by the finding that in the two types of erythrocyte membranes the ratios between the 32P-labeling of their phosphorylserine and phosphorylthreonine residues were different.

Serum laminin P1 in chronic viral hepatitis: correlations with liver histological activity and diagnostic value.

Laminin is a major basement membrane-associated, non-collagenous glycoprotein of the extracellular matrix and is deposited in the space of Disse during sinusoidal capillarisation. Laminin P1, a pepsin-resistant fragment originating from the central portion of the cross-shaped laminin molecule, is detectable in serum and has been related to liver fibrosis and portal hypertension. In this study we investigated the behaviour of serum laminin P1, measured by radioimmunoassay, in a homogeneous group of 95 patients suffering from chronic viral hepatitis, types C or B, in order to determine the relationships between serum laminin P1 and each of the main histological aspects of the disease process (i.e. portal-periportal activity, lobular activity and fibrosis), which were assigned numerical scores. Moreover, we computed, at several cut-off levels, the sensitivity, specificity and positive and negative predictive values of laminin P1 in detecting both necroinflammatory activity and fibrosis in the liver. The results show that serum laminin P1 levels parallel the severity of liver disease, the highest laminin concentrations being observed in cirrhotic patients. They suggest also that serum laminin P1 should be considered a marker of the liver disease process as a whole, rather than a marker exclusively linked to fibrosis. Nevertheless, the usefulness of serum laminin P1 measurement, as investigated in this study, seems too limited to be recommended for routine clinical practice.

Serum laminin and type III procollagen in chronic hepatitis C. Diagnostic value in the assessment of disease activity and fibrosis.

Laminin P1 (pepsin-resistant fragment of laminin) and aminoterminal peptide of type III procollagen are measurable in serum and are now considered useful serum markers of fibrogenesis and inflammation in chronic liver diseases. However, very few studies thus far have focused on assessing the diagnostic value of these markers in detecting fibrosis and necro-inflammatory activity in chronically diseased liver. The aim of the present study was therefore to investigate the correlations of laminin and type III procollagen with liver histology and to compare their diagnostic value in detecting the degree of liver fibrosis and necro-inflammatory activity in a homogeneous group of 99 patients suffering from chronic hepatitis C, and lacking other factors which can directly affect the serum levels of the two markers. Both these serum markers were measured by radioimmunoassay, employing commercially available kits. The three main aspects of liver pathology, i.e. portal-periportal activity, lobular activity and fibrosis, were histologically evaluated and semiquantitatively expressed by numerical scores. The results of this study show that laminin and type III procollagen were both positively correlated with the histological scores for portal-periportal activity and with those for fibrosis, whereas no significant correlation was observed between each of the two serum markers and the histological scores for lobular activity. The sensitivity and specificity of laminin and type III procollagen in detecting histological aspects of fibrosis and disease activity in liver, computed at various cut-off levels, showed overlapping trends for the two markers; however, the diagnostic value was in general rather low, whatever the cut-off considered. We therefore conclude that the 'static' measurement of both serum laminin and type III procollagen is of limited value for individual diagnosis of liver damage.

Membrane polyunsaturated fatty acids and lithium-sodium countertransport in human erythrocytes.

Two groups of individuals, 26 normotensive normolipemic and 37 normotensive hyperlipemic, all without family history of hypertension have been selected in attempt to demonstrate whether Li-Na countertransport of erythrocytes is influenced by plasma and membrane lipid composition. The maximal rate of Li-Na countertransport was elevated in hyperlipemics (0.344 +/- 0.168 vs 0.220 +/- 0.074 mmol/l erythrocytes/h). This difference is highly significant. Hyperlipemics had different composition of membrane lipids than normals. The most important variations were: increase of palmitic, palmitoleic and total saturated fatty acids (SFA) as well as increase of cholesterol/phospholipids ratio (C/PL); in contrast, hyperlipemics had a reduced amount of linoleic acid and total unsaturated fatty acids (UFA) as well as total polyunsaturated fatty acids (PUFA). Consequently, UFA/SFA and PUFA/SFA ratios were lower than in normals. Li-Na countertransport was negatively correlated with the amount of PUFA (P less than 0.02), whereas it was positively correlated with the following parameters: oleic/linoleic ratio (p less than 0.02), monounsaturated fatty acids/polyunsaturated fatty acids ratio (p less than 0.03) as well as with the SFA + monounsaturated fatty acid/PUFA ratio (p less than 0.03). These findings suggest that the V max of Li-Na countertransport in erythrocytes is influenced by the lipid composition of the membrane.

Elevation of red cell sodium-lithium countertransport in hyperlipidemias.

Red cell Na-Li countertransport was measured in 78 normal subjects, 64 patients with essential hypertension, and 67 patients with hyperlipidemias. Both hypertensive and hyperlipidemic patients had elevated Na-Li countertransport compared to normal controls (p less than 0.001). Subjects with hyperlipidemia and hypertension had higher countertransport (p less than 0.02) than patients with only hyperlipidemia. Normotensive hyperlipidemic subjects had higher countertransport than normotensive and normolipidemic controls (p less than 0.02). This suggest that hypertension and high plasma lipids can influence independently the Na-Li countertransport. In another group of 52 normotensive subjects, Na-Li countertransport was positively correlated with serum total and free (unesterified) cholesterol, phospholipids and triglycerides. No correlations were found with HDL-cholesterol or HDL-phospholipids. A very high positive correlation was found between Na-Li countertransport and plasma acetylcholinesterase (p less than 0.005). These findings suggest that plasma lipids, probably through membrane lipids, can affect the maximal rate of the Na-Li exchange in red cells. The relationship between plasma or membrane lipids and cation transport should be further studied in erythrocytes and other cells.

Effects of five-day versus one-day infusion of iloprost on the peripheral microcirculation in patients with systemic sclerosis.

OBJECTIVE: To evaluate the effects of iloprost infusion on the microcirculation in patients suffering from severe Raynaud's phenomenon secondary to systemic sclerosis. METHODS: Eight patients received a 7-hour infusion of iloprost for five consecutive days and then for one day 3 months later. The effects on vascular distensibility were evaluated by piezoelectric plethysmography before and after the treatment and at 2, 4 and 6 weeks. RESULTS: The beneficial effects on the peripheral microcirculation were statistically significant after five days of infusion (distensibility index: 0.18 +/- 0.01 vs 0.23 +/- 0.01, p < 0.002) and lasted for less than four weeks, whereas no difference (0.22 +/- 0.04 vs 0.24 +/- 0.02, p: ns) was seen after one day of treatment. One patient suffered from typical angina pectoris with electrocardiographic changes of the ST wave detected during the infusion. CONCLUSION: Our results show that a five-day infusion of iloprost has an effect which lasts from two to four weeks; after four weeks the distensibility index returned to the baseline value. The one-day infusion had no effect on the vascular bed, studied by the piezoelectric pletysmographic method. Treatment with five consecutive days of infusion every four weeks is an impracticable scheme to adopt, however. We have therefore instituted a treatment schedule of a single daily infusion every four weeks with the aim of maintaining the effects induced by the initial five-day infusion. The preliminary results obtained with this schedule are reported.

Analysis of the T cell receptor repertoire in rheumatoid arthritis.

OBJECTIVE: To evaluate whether there is a restricted T cell receptor repertoire in rheumatoid synovium and to analyse the CDR3 region of the V beta families found to be more expressed in the synovial membrane than in the peripheral blood, in order to ascertain the presence of clonotypic expansion of T lymphocytes. METHODS: The level of expression of individual V beta and V alpha families of the TCR was evaluated in paired synovial membrane and peripheral blood T cells from 8 female patients affected by rheumatoid arthritis, using the RT-PCR method. Nucleotide sequences of the CDR3 region of some V beta families were analysed in order to identify the presence of conserved sequences. Sequencing was carried out with the dideoxy chain termination method using modified T7 DNA polymerase. RESULTS: All of the V alpha and V beta families were amplified in both compartments of the 8 patients. Four patients did not show any preferential expression of the TCR alpha or beta chains in synovium compared with peripheral blood. The other 4 patients showed increased expression of one or more V alpha and/or V beta families in the synovium. We did not find any correlation between the duration of disease, rheumatoid factor status, HLA-DR type and the V gene families which were elevated in the synovium. Analysis of the CDR3 region showed the presence of conserved amino acid sequences in the synovium, but not in the peripheral blood. CONCLUSION: The V families found to be increased in 4 of the 8 patients studied were different, except for V beta 1 which was more highly expressed in 2 patients. The presence of conserved amino acid sequences in the CDR3 region is consistent with an antigen-driven T cell expansion at the site of autoimmune inflammation. These findings do not support our original hypothesis of the possible usefulness of therapy based on the inactivation or elimination of presumed pathogenic T cells using TCR-derived peptides or monoclonal antibodies against particular TCRs.

Alternative pathway for complement activation triggered by human liver plasma membranes.

Liver plasma membranes (LPM) prepared from normal hepatocytes by centrifugation in sucrose discontinuous gradient, are capable of haemolysing PNH-like cells in the presence of complement or complement plus EGTA or MG2+ ions. In contrast, EDTA or Ca2+ ions inhibit the lysis. The total complement lytic activity is reduced by some 40% when fresh serum is incubated with LPM, whereas the total amount of C4 remains constant. The cross-immunoelectrophoresis studies of fresh serum incubated with LPM demonstrate the appearance of C3 breakdown products, which suggests the activation of the alternative complement pathway. In contrast, the sucrose test, which proceeds mainly through the classical complement pathway, is inhibited by LPM. The possible role of complement in liver disease is discussed.

Serum folate binding capacity in patients with solid tumors.

Total and unsaturated folate binding capacity (TFBC-UFBC) was measured in 44 normal volunteers and in 77 patients with solid tumors; of them 31 had a lung cancer, 18 a cancer of the gastrointestinal tract (GI), and 28 a breast cancer. With the exception of patients with cancer of the stomach, all the other groups showed a significant increase in TFBC. An increase in UFBC was statistically observed in patients with lung cancer and cancer of the GI tract. No correlation was observed in breast cancer between the presence of hormone receptors on cancer tissue and the value of TFBC. However, a significant increase in TFBC was noted in this group of patients when metastases were present.

Use of computerized digital thermometry for diagnosis of Raynaud's phenomenon.

The authors have used computerized digital thermometry for the instrumental diagnosis of Raynaud's phenomenon; such a technique enables them to evaluate the temperature of the ten fingers of the hands separately in baseline conditions, during and after the "cold test." In baseline conditions the mean digital skin temperature was 31.2 degrees C (SD 1.67) in control subjects and 26.8 degrees C (SD 2.84) in patients suffering from Raynaud's phenomenon (p less than 0.001). During the cold test the mean skin temperature decreased to 12.7 degrees C (SD 1.94) in control subjects and to 13.0 degrees C (SD 1.67) in patients (p = n.s.). The mean final skin temperature, at the end of the recovery period after the cold test, was 31.1 degrees C (SD 1.76) in controls and 21.9 degrees C (SD 2.78) in patients (p less than 0.001). The sensitivity of the computerized digital thermometry was high (63.6% and 92.7% for basal and final temperature, respectively), while the specificity was 100% for both values. In conclusion, computerized digital thermometry is a useful technique for the diagnosing and quantifying the extent of Raynaud's phenomenon.

Controlled comparison of ketanserin and nifedipine in Raynaud's phenomenon.

Twenty-eight patients suffering from either primary or secondary Raynaud's phenomenon were treated with nifedipine and ketanserin. Each patient was treated with one of the two drugs administered after an adequate washout period. Furthermore each patient was submitted before and after treatment with each drug to computerized digital thermometry to evaluate the therapeutic response. The data obtained during the intake of the two drugs at zero, five, and twenty-three minutes were compared with thermometry-relevant baseline data at the same periods. Ketanserin proved to be useful in the treatment of Raynaud's phenomenon and statistically significantly superior (alpha less than 0.05) with respect to nifedipine in the thermometric controls and also in the subjective evaluation of the patients (p less than 0.02). In this study nifedipine did not show particular efficacy. Furthermore only 2 patients had to discontinue treatment with ketanserin, whereas 8 had to discontinue treatment with nifedipine (p less than 0.001).

[Persistent generalized lymphadenopathy: pre-AIDS. First description of a case observed in Italy]. / Linfadenopatia persistente generalizzata: pre-AIDS. Prima descrizione di un caso osservato in Italia.

Persistent Generalized Lymphadenopathy (PGL) is considered a possible early stage of AIDS (pre-AIDS), caused by the same virus and characterized by the same immunologic abnormalities. So far, no case of PGL has been reported in Italy: therefore we describe a typical clinical history, immunologic studies and lymph-node histology of a young italian patient affected by PGL. We treated him with thymocyte protein extract (TP-1). We think PGL is not rare in Italy and probably a percentage of cases, especially in heroin addicts and homosexual males, is not recognized.

[Pulmonary mucosa-associated lymphoid tissue lymphoma in a patient with myasthenia gravis]. / Linfoma polmonare del tessuto linfoide associato alla mucosa in una paziente affetta da miastenia grave.

Mucosa-associated lymphoid tissue lymphomas are a subgroup of non-Hodgkin's lymphoma. The lung is the most frequent non-gastrointestinal organ they affect. Pulmonary mucosa-associated lymphoid tissue lymphoma usually appears as a solitary mass often accidentally discovered on chest radiography. Diffuse, bilateral involvement is rare. The association of mucosa-associated lymphoid tissue lymphoma with autoimmune diseases has been reported, and a pathogenetic role has been suggested for the autoimmune process in its development. Optimum management has not yet been standardized. The case described here is a mucosa-associated lymphoid tissue lymphoma with multiple, unusually large opacities involving both lungs. The patient, a 55-year-old woman, also suffered from myasthenia gravis, an autoimmune disease characterized by an autoaggressive process against the acetylcholine receptors. Whereas other autoimmune diseases such as rheumatoid arthritis, polymyositis, and fibrosing alveolitis have been correlated with mucosa-associated lymphoid tissue lymphoma, an association between this lymphoma and myasthenia gravis has not yet been reported. Complete resolution of the pulmonary opacities was obtained with cyclophosphamide treatment. It continues at 15 months after the suspension of therapy.

Search of HIV DNA by polymerase chain reaction in the urine sediments of seropositive individuals.

We have utilized the polymerase chain reaction (PCR) technique to detect proviral sequences of the human immunodeficiency virus (HIV) from urine sediments of HIV seropositive individuals. HIV amplified DNA sequences, easily detectable in peripheral blood cells, were not found in the urine sediments of the seropositive individuals. This finding is in agreement with previous observations that the urines of seropositive individuals are not infective.