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Biomedical subjects

D Conte

Publications and source records attributed to D Conte.

At least 127 records · Page 7Linked to original sources

Effectiveness of erythrocytapheresis in idiopathic hemochromatosis. Report of 14 cases.

Thirteen men and one woman (mean age 48.8 yr +/- 6.9, range 36-63) with idiopathic hemochromatosis were treated by erythrocytapheresis. Iron depletion followed 9.60 months treatment (median 24), with 21-203 erythrocytaphereses (mean 93 +/- 61) and total iron removal of 4.2-40.6 g (mean 19 +/- 11.9). Trasferrin saturation decreased from 90 +/- 8.7% to 17 +/- 10.6% and serum ferritin from 3164 micrograms/L +/- 1488 to 60.5 micrograms/L +/- 77.5, and liver iron content normalized in all cases. Initial serum ferritin in the patients who were iron-depleted at 18 months (50%, cumulative percentage) was significantly lower than in those still iron loaded at that time (2280 micrograms/L +/- 940 vs 4049 micrograms/L +/- 1444, p less than 0.02). Clinical improvement was noted in all cases with about a 30% decrease in insulin requirement in most diabetics. Thus erythrocytapheresis appears to be effective and safe in obtaining iron depletion in idiopathic hemochromatosis.

Adult↗

HBV, HDV and HIV infections in 242 drug addicts: two-year follow-up.

Of 242 north Italian heroin addicts, 24 (9.9%) were HBsAg positive. HBeAg was positive in two of them (8.3%), anti-HBe in 16 (66.6%) and anti-HDV in 21 (87.5%). Of the 218 HBsAg negative, 182 (83.5%) had anti-HBc, 72 (33.0%) anti-HBe and 97 (44.5%) anti-HBs. One-hundred-eighty-five drug addicts were anti-HIV positive (76.4%); 77 of these (41.6%) were asymptomatic, 93 (50.3%) had PGL and 15 (8.1%) ARC. T4+ cell count was significantly lower in subjects with ARC as was T4+/T8+ ratio in subjects with PGL and ARC. During a median follow-up of 9.5 months (range 4-25), we observed three new cases of hepatitis (two caused by NANBV and one by HBV with HDV coinfection) and one new HIV infection. Ten anti-HIV positive subjects developed PGL and one AIDS.

Acquired Immunodeficiency Syndrome↗

HIV and HBV infection in intravenous drug addicts from northeastern Italy.

Three hundred and two intravenous drug addicts (IVDA) from five towns in Northeastern Italy were studied. Of the males, 37/249 (14.8%) were homosexuals and of the females, 29/53 (54.7%) were prostitutes; 118 (39.0%) were alcoholics. AST levels were abnormal in 31.8%, ALT in 45.7%, GTP in 36.4%, and bilirubin in 14.6%. The prevalence of HBsAg (13.9%) and HBeAg (21.4% of HBsAg positive) was significantly higher than in 2,983 controls (4.2% and 6.3%, p less than .001 and p less than .02, respectively). Of the HBsAg positive subjects, 51.7% had anti-HDV antibodies. Among 260 HBsAg negative cases, 146 (56.2%) were anti-HBs and anti-HBc positive, 76 (29.2%) were anti-HBc positive and anti-HBs negative (25 anti-HBe positive and 51 anti-HBe negative), and 38 had no HBV markers. Anti-HIV ELISA positive subjects came to 70.5% (triplicate determination with absolute concordance) and Western blot analysis confirmed the results in 99.1% of ELISA positive and 100% of ELISA negative subjects. The prevalence of anti-HIV was significantly higher in anti-HBc positive than negative cases (p less than .02), even excluding HBsAg positive subjects. Cases negative for HIV and HBV had a significantly lower median duration of drug abuse than those with past or present infection (36 vs 60 months, p less than .001). HIV-related diseases were present in 56.3% of the cases (120/213; PGL in 94, ARC in 24, and AIDS in two).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Nuclear and cytosolic estrogen receptors in human colon carcinoma and in surrounding noncancerous colonic tissue.

The measurement of estrogen as well as progesterone receptors has been applied clinically to predict the effectiveness of endocrine therapy in patients with breast or endometrial carcinoma. The presence of cytosolic estrogen receptors in human colorectal carcinomas has been reported by several different groups during the past 10 yr. The aim of our current study was to evaluate the estrogen binding activity in the nuclear and cytosolic fractions of these carcinomas, as well as in surrounding noncancerous colonic tissue. Twenty-six patients, operated on for colorectal carcinoma, were studied: 16 were men and 10 were postmenopausal women, mean age 61 yr (range 43-78 yr). In neoplastic tissue, cytosolic estradiol receptors were detected in 42.3% of the patients (women 40%, men 43.7%). The values for cytosolic estrogen receptor ranged from 118 to 1214 fmol/g wet colon. Nuclear estrogen receptors were detectable in 46.1% of the patients (women 40%, men 50%) and their values displayed a range from 3.4 to 2554 fmol/g wet colon. In 30.7% of the patients, both nuclear and cytosolic receptors were demonstrated. In 38.4% of the patients, receptors were found in neither cytosol nor nuclei. Receptor positivity in men was most frequently associated with tumors removed from the rectum, and those with Dukes' classification of C1. In the surrounding noncancerous tissue cytosolic estrogen receptors were also detected (range 133-1105 fmol/g wet colon) and were present in 34.6% of the patients (women 30%, men 37.5%). Nuclear estrogen receptors (range 225-1105 fmol/g wet colon) were detected in 57.6% of the patients (women 40%, men 68.7%). In 23% of the patients, both nuclear and cytosolic receptors were demonstrated. In 30.7% of the patients, no receptors were found in either cytosol or nucleus. Therefore, the presence of cytosolic or nuclear estrogen receptors, or both, in 61.6% of human colorectal cancer specimens emphasizes the need to evaluate both forms of these receptors for studies of potential hormone dependence in these tumors.

Adenocarcinoma↗

Stainable iron in gastric and duodenal mucosa of primary hemochromatosis patients and alcoholics.

The presence of iron in gastric and duodenal mucosa was investigated with Perl's stain in endoscopic biopsies from 13 patients with overt primary hemochromatosis, 10 chronic heavy alcohol abusers, and 10 patients with nonulcer dyspepsia. In the primary hemochromatosis patients marked iron deposition was found in cells at the base of glands in the gastric body and antrum in nine cases, and in crypt cells and Brunner gland cells of the duodenum in six. Iron was detected in the lamina propria of the stomach in five and duodenum in four cases. A similar distribution of iron overload, usually of lesser degree, was also observed in five alcoholics. Serum ferritin levels and the degree of gastric and/or duodenal iron deposits did not correlate in either hemochromatosis patients or alcoholics. No gastric or duodenal siderosis was observed in nonulcer dyspepsia cases. The absence of gastric and duodenal stainable iron in some hemochromatosis patients and its presence in some alcoholics suggests that the diagnostic value of upper gastrointestinal biopsy in primary hemochromatosis is limited.

Adult↗

Lactose malabsorption and intolerance in Italians. Clinical implications.

Lactose malabsorption was assessed by the hydrogen breath test in 40 Italian patients with irritable bowel syndrome and 42 controls without abdominal disturbances. Sixty-five percent of patients were "low milk consumers" (0-250 ml milk per day) compared with 38% of controls (P less than 0.02). Lactose loads of 25 and 50 g caused malabsorption in 82.5 and 87.5% patients and in 55 and 62% controls, respectively (patients vs controls P less than 0.02). Malabsorption was more frequent in the "low milk consumers" group (P less than 0.05). During a four-month lactose-free diet as the only treatment 7.5% of patients became symptom-free (and remained so for a further eight-month diet), 52.5% improved, and 40% showed no change.

Adult↗

Clinical, biochemical and histological features of primary haemochromatosis: a report of 67 cases.

In 67 patients (mean age 51 years, range 26-79), at diagnosis of primary haemochromatosis (PH), grade III or IV liver iron overload was present in all cases, cirrhosis in 85%, transferrin saturation greater than 80% in 75%, serum ferritin greater than 1000 micrograms/l in 84%, and overt diabetes in 48%. Alcohol intake was greater than 150 g/day in 11 patients; six were chronic hepatitis B surface antigen (HBsAg) carriers. HLA-A3 and B7 antigens were present in 64% and 23% versus respectively 22% (p less than 0.01) and 9% (p less than 0.025) in controls. Iron overload was found in the stomach, duodenum, skin and bone marrow in 57, 43, 45 and 59% of the patients studied. Sixty-three patients were followed for 1-260 months (median 24); 43 received regular iron-depleting treatment and 20 did not because of liver failure, cancer or refusal. Cumulative survival was 79%, 67% and 61% at 1, 4 and 10 years, respectively. Ten patients died from hepatocellular carcinoma and two from extrahepatic cancer. The early high mortality rate was due to some cases of advanced disease or cancer. Cumulative survival in the regularly treated group was 95% at 1 year and 91% at 4 and 10 years, which was higher than in the untreated group.

Adult↗

Role of arachidonate metabolism on the in vitro release of luteinizing hormone and prolactin from the anterior pituitary gland: possible involvement of lipoxygenase pathway.

The aim of the present study was to evaluate whether arachidonic acid metabolism may play a role on luteinizing hormone (LH) and prolactin (PRL) release directly at the pituitary level. To this purpose, exogenous arachidonic acid, alone or in presence of inhibitors of cyclooxygenase (indomethacin:IND) and lipoxygenase pathways (nordihydroguaiaretic acid:NDGA), was added to perfused rat anterior pituitary cells. PGE, PGF alpha, LH and PRL levels present in the eluate were assayed with specific RIA methods. Both PGE and PGF alpha show a dose-related response after the addition of increasing doses of arachidonic acid. The addition of 0.05 mM arachidonic acid induces an increase of LH and PRL. The addition of IND to the perfusion medium highly potentiates the stimulatory effects induced by arachidonic acid on LH and PRL release. On the contrary, the addition to the medium of either NDGA or IND plus NDGA completely reverses the stimulatory action induced by arachidonic acid alone. The present results suggest that: adenohypophyseal cells are able to metabolize exogenous arachidonic acid; arachidonic acid induces an elevation in LH and PRL levels; lipoxygenase pathway metabolite(s) are likely involved in these activities, and the site of action of arachidonic acid is at the pituitary level.

Animals↗

Transmembrane signals mediating neural peptide secretion: role of protein kinase C activators and arachidonic acid metabolites in luteinizing hormone-releasing hormone secretion.

The present experiments were designed to determine the effects of different activators of protein kinase C on the secretion of LHRH from median eminence nerve terminals incubated in vitro. The release of prostaglandin E2 (PGE2), a metabolite of arachidonic acid intimately involved in the secretion of LHRH, was also evaluated. Synthetic diacylglycerol [1,2-didecanoylglycerol (DiC10)] significantly enhanced PGE2 release in a concentration-dependent manner. Blockade of phospholipase A2 (PLA2) activity nullified this effect. LHRH release, on the other hand, was not increased by DiC10. However, in the presence of a lipoxygenase inhibitor, DiC10 produced a concentration-related increase in LHRH release, which paralleled that in PGE2. Phospholipase C (PLC) increased both PGE2 and LHRH secretion. Again, blockade of the lipoxygenase pathway enhanced the release of LHRH by PLC without affecting the stimulated secretion of PGE2. A phorbol ester, phorbol 12,13-dibutyrate (PDBu), markedly increased LHRH secretion while inducing a modest increase in PGE2 release. Both effects of PDBu were unaffected by lipoxygenase inhibition. DiC10, PDBu, and PLC significantly augmented LHRH secretion from tissues in which metabolism of arachidonic acid had been prevented by inhibition of both cyclooxygenase and lipoxygenase pathways, suggesting that activation of protein kinase C, independent of PLA2 activation, can lead to the secretion of this neural peptide. Some lipoxygenase metabolites had either no effect on [5- and 15-hydroxyeicosatetraenoic (5- and 15-HETE)] or induced a marginal stimulation of (12-HETE) LHRH release. At certain concentrations, 12-HETE enhanced the stimulatory effect of the phorbol ester on LHRH release. Our results suggest that activation of protein kinase C can stimulate LHRH secretion from nerve terminals in vitro and, further, that diacylglycerol may represent an important intracellular messenger participating in the events leading to LHRH secretion. In addition, stimulation with DiC10 and PLC uncovered inhibitory [unknown arachidonic acid metabolite(s) via lipoxygenase] and stimulatory (PGE2 via cyclooxygenase) pathways through with arachidonic acid metabolites may participate in the intracellular transduction of signals modulating neural peptide secretion.

Animals↗

Role of seminal prostaglandins in male fertility. II. Effects of prostaglandin synthesis inhibition on spermatogenesis in man.

The effect of prostaglandin biosynthesis inhibition has been studied in two groups of infertile oligozoospermic patients with high or normal-low seminal prostaglandin (PG) levels. PGE and 19-OH PGE were assayed by means of a gas chromatographic method and the most important seminal parameters (volume, concentration, motility and morphology of spermatozoa) were evaluated in basal conditions and at the end of indomethacin treatment, at a daily oral dose of 100 mg for thirty days. A drop in prostaglandin levels following indomethacin was observed in both groups of patients but only in the group with high concentrations of prostanoid derivates the prostaglandin inhibition was correlated with a significant improvement in sperm count and motility.

Adult↗

Diacylglycerol and phorbol esters enhance LHRH and prostaglandin E2 secretion from median eminence nerve terminals in vitro.

The present experiments were designed to evaluate the role of protein kinase C activation on the secretion of the neural peptide, LHRH, from hypothalamic nerve terminals in vitro. Two specific protein kinase C activators, diacylglycerol (1,2-didecanoylglycerol, DiC10) and a phorbol ester (12,13-dibutyrate, PDBu) were used as probes. In addition to LHRH, secretion of prostaglandin E2 (PGE2) was also measured, since previous studies from our laboratory indicate that this arachidonic acid metabolite is intimately involved in the LHRH secretory process. PDBu at a dose of 200 nM significantly enhanced LHRH secretion from median eminence nerve terminals; in addition, a more modest but significant stimulation of PGE2 release was also observed. DiC10 (100 microM), on the other hand, enhanced PGE2 release but had no clear effect on LHRH secretion. Release of LHRH, however, was clearly stimulated when the lipoxygenase inhibitor nordihydroguaiaretic acid was added to the medium, suggesting that some arachidonic acid metabolites are inhibitory to LHRH secretion. The results indicate that protein kinase C activation leads to an enhanced secretion of LHRH. In addition, they suggest that 1,2-diacylglycerol may also activate the formation of arachidonoyl residues inhibitory to LHRH release.

Animals↗

Effect of loperamide and naloxone on mouth-to-caecum transit time evaluated by lactulose hydrogen breath test.

The effect of loperamide and naloxone on mouth-to-caecum transit time was evaluated by the lactulose hydrogen breath test in four men and four women. Each subject underwent tests during the administration of placebo, loperamide (12-16 mg po), naloxone (40 micrograms/kg/h by a three-hour intravenous infusion), and loperamide plus naloxone, carried out at intervals of one or two weeks. The transit time was significantly longer after loperamide, and this effect was antagonised by the concomitant administration of naloxone whereas naloxone administered alone had no effect on mean transit time. No clinically important side effects were reported.

Adult↗

Effects of the "vascular factor" on platelet and vascular arachidonic acid metabolism in man.

The effects of a drug with hemostatic action, "Vascular Factor" (V.F.), on platelet and vascular arachidonic acid metabolism were evaluated in man to establish the lack of side effects on platelet aggregation. Plasma levels of 6-keto PGF1 alpha and thromboxane B2 were determined by RIA in healthy volunteers undergoing treatment with V.F. Results indicate that basal values obtained in these compounds do not present significant variations following treatment with V.F. On the basis of these results, the possibility of administering this drug in atherosclerotic patients is further confirmed.

6-Ketoprostaglandin F1 alpha↗

Effect of ascorbic acid on desferrioxamine-induced urinary iron excretion in idiopathic hemochromatosis.

The effect on urinary iron excretion (UIE) of vitamin C administered orally 2 h after the start of an 8-hour desferrioxamine (DF) i.v. infusion was studied in 12 patients with untreated idiopathic hemochromatosis (IH). Mean +/- SEM basal UIE of 324.6 +/- 84.6 micrograms/24 h increased after a 1-gram i.v. DF infusion to 8,778.5 +/- 1,191.4 micrograms/24 h; when vitamin C 1 or 2 g were added to DF i.v. infusion, there were further increases to 11,241.5 +/- 1,486.1 (p less than 0.01) and 13,531.2 +/- 1,697.2 micrograms/24 h (p less than 0.05 versus the last value), respectively. Basal UIE did not significantly increase after oral vitamin C administration alone. No side effects were observed.

Adult↗