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F Orlandi

Publications and source records attributed to F Orlandi.

At least 19 recordsLinked to original sources
PubMed1999

Intracellular pathways mediating Na+/H+ exchange activation by platelet-derived growth factor in rat hepatic stellate cells.

BACKGROUND & AIMS: The Na+/H+ exchanger is the main intracellular pH regulator in hepatic stellate cells (HSCs), and its activity is increased by platelet-derived growth factor (PDGF). Amiloride, an Na+/H+ exchange inhibitor, reduces PDGF-induced HSC proliferation, suggesting that the Na+/H+ exchanger plays a role in regulating HSC proliferative response. The aim of this study was to characterize the intracellular pathways mediating activation of the Na+/H+ exchanger by PDGF in HSCs. METHODS: The activity of the Na+/H+ exchanger and HSC proliferation rate were evaluated under control condition and after incubation with PDGF in the absence or presence of specific inhibitors of the main intracellular pathways of signal transduction. Na+/H+ exchange protein expression was evaluated by means of Western blot. RESULTS: PDGF induced a significant increase in the activity of the Na+/H+ exchanger without modifying protein expression. Inhibition of the calcium/calmodulin- and protein kinase C-dependent pathways resulted in a significant inhibition of both Na+/H+ exchange activity and of PDGF-induced HSC proliferation. The involvement of the two pathways was confirmed by showing that incubation of HSCs with both phorbol-12-myristate-13-acetate, a potent protein kinase C activator, and thapsigargin, which increases intracellular calcium levels, significantly increased both the Na+/H+ exchanger activity and HSC proliferation rate. Inhibition of the protein kinase A pathway did not modify either PDGF-induced Na+/H+ exchange activation or PDGF-induced HSC proliferation. On the contrary, inhibition of the mitogen-activated protein kinase- and of phosphatidylinositol 3-kinase-dependent pathways significantly reduced PDGF-induced HSC proliferation without affecting the activity of the Na+/H+ exchanger. CONCLUSIONS: Activation of the Na+/H+ exchanger by PDGF in HSCs is mediated by calcium/calmodulin- and protein kinase C-dependent pathways. PDGF-induced HSC proliferation is mediated by Na+/H+ exchange-dependent and -independent pathways.

Animals↗
PubMed1999

The Na+/H+ exchanger modulates the fibrogenic effect of oxidative stress in rat hepatic stellate cells.

BACKGROUND/AIMS: Oxidative stress is associated with liver fibrosis in vivo and with hepatic stellate cell (HSC) activation in vitro, but the intracellular mechanisms mediating these effects are mostly unknown. The Na+/H+ exchanger plays a key role in regulating the cell cycle, and is involved in HSC proliferation. Its role in different HSC features, such as collagen accumulation, is still unknown. We thus evaluated if the Na+/H+ exchanger modulates the fibrogenic effect of oxidative stress in rat HSC. METHODS: HSC were incubated with 0.1 mM ferric nitrilotriacetate complex (FeNTA). Intracellular hydroperoxides and malonildialdehyde (MDA) levels in the culture media were measured by the dichlorofluorescein and TBARS method, respectively. Intracellular pH and Na+/H+ exchanger activity were measured using the fluorescent dye BCECF. Cell proliferation was measured by immunohistochemistry for bromodeoxyuridine incorporation. Collagen type I accumulation in the culture media was measured by ELISA. RESULTS: HSC incubation with FeNTA resulted in a significant production of intracellular hydroperoxides and MDA, associated with increased Na+/H+ exchange activity and baseline intracellular pH (pHi). Exposure of HSC to FeNTA significantly enhanced the number of proliferating HSC and collagen type I levels in the culture medium. All these effects were reversed by the antioxidant resveratrol and by the Na+/H+ exchanger inhibitor amiloride. CONCLUSIONS: This study indicates that the Na+/H+ exchanger might represent a common mediator of the different effects induced by oxidative stress on HSC. The reduction in cell proliferation and collagen synthesis induced by amiloride could represent a new therapeutic challenge in liver fibrosis.

Animals↗
PubMed1998

Galectin-3 is a presurgical marker of human thyroid carcinoma.

Galectin-3 is a carbohydrate-binding protein endowed with an affinity for beta-galactosides. It has been shown to play an important role in cell-cell and cell-matrix interactions and in pre-mRNA splicing. Furthermore, it is involved in the control of cell growth, neoplastic transformation, and metastasis. Interestingly, high levels of galectin-3 expression have been recently described in malignant thyroid neoplasias, but not in adenomas or in normal thyroid tissue. We investigated galectin-3 expression in human presurgical specimens obtained by fine-needle aspiration biopsy. We analyzed galectin-3 expression by immunoperoxidase staining in both paraffin-embedded cytological thyroid sediments (cell blocks) obtained by fine-needle aspiration biopsy and their histological counterparts. A total of 64 samples were examined: 17 follicular carcinomas; 18 papillary carcinomas; and 29 follicular adenomas. All cell blocks and histological samples of papillary carcinomas expressed high levels of galectin-3 at either the cytoplasmic or nuclear level. Among follicular carcinomas, all histological samples expressed galectin-3, whereas 14 of 17 corresponding cell blocks were positive in the cytoplasm. No evidence of cytoplasmic galectin-3 expression was observed in 26 of 29 follicular adenomas. Hence, cytoplasmic galectin-3 staining seems to be a reliable, easy, and cheap marker for presurgical diagnosis of follicular carcinomas and an even more suitable one for papillary carcinomas.

Adenocarcinoma, Follicular↗
PubMed1998

Comparison of urinary free beta (hCG) and beta-core (hCG) in prenatal screening for chromosomal abnormalities.

To evaluate the potential utility of free beta (hCG) and beta-core (hCG) in a prenatal screening protocol for Down syndrome we analysed these markers in dried maternal urine specimens from 163 control, 13 Down syndrome and 5 trisomy 18 pregnancies from 8 to 25 weeks' gestation. All results are reported after normalization for urinary creatinine determined by modified Jaffe reagent assay. The correlation of urinary free beta (hCG) and urinary beta-core (hCG) was 0.61 in controls and 0.93 in Down syndrome. Median MoM values in Down syndrome were 2.42 for urinary free beta (hCG) and 2.40 for beta-core (hCG). In trisomy 18 the Median MoM was 0.35 and 0.34 for free beta (hCG) and beta-core (hCG), respectively. The degree of elevation observed in DS cases with urinary free beta (hCG) is consistent with previous reports. Studies of beta-core (hCG) in Down syndrome have yielded discrepant results. In this study, beta-core (hCG) in Down syndrome is lower than values observed in early reports but consistent with more recent reports.

Chorionic Gonadotropin, beta Subunit, Human↗
PubMed1998

Observer agreement in endoscopic assessment of ulcerative colitis.

BACKGROUND: Colonoscopy is the investigation of choice to evaluate ulcerative colitis, but the reliability of the assessment of endoscopic signs is not clear. AIMS: The aim of this study was to evaluate interobserver agreement for the identification of endoscopic lesions typical of ulcerative colitis, and the influence of training. MATERIAL AND METHODS: Four experienced observers and 11 endoscopists under training assessed 49 still images selected from endoscopic video recordings. RESULTS: The agreement rate between experienced observers was excellent or good (k > 0.39) for recognition of 10 out of 14 signs or patterns (loss of vascular pattern, erythema, oedema, granular mucosa, blood, pseudopolyp, erosion, ulcer, normal pattern, severe activity), and was poor for pus, stricture, mild activity, moderate activity. The rates between endoscopists under training were excellent or good for 6 items (loss of vascular pattern, erythema, oedema, pseudopolyp, normal pattern, severe activity). CONCLUSIONS: Trained observers can reproducibly record most endoscopic signs of ulcerative colitis. A reliable overall scoring of severity should be based on a simple three-grading scale, i.e. normal pattern, moderate activity, severe activity. Acceptable agreement rates can be obtained by endoscopists under training on some well-defined endoscopic appearances.

Colitis, Ulcerative↗
PubMed1997

First-trimester screening for fetal aneuploidy: biochemistry and nuchal translucency.

Maternal dried whole-blood specimens were collected prospectively from 2010 singleton pregnancies between 9 + 0 and 13 + 4 weeks that included 18 chromosomally abnormal pregnancies (11 Down's syndrome, four trisomy 18, two trisomy 13 and one triploidy). A subset of 744 pregnancies underwent ultrasound nuchal translucency measurement and included seven Down's syndrome, four trisomy 18, two trisomy 13 and one triploidy. Patients were evaluated for risk of Down's syndrome and trisomy 18 based on biochemistry (free beta-human chorionic gonadotropin and pregnancy-associated plasma protein A), nuchal translucency and the combination of both. In prospective biochemical screening, false-positive rates for Down's syndrome and trisomy 18 were 5.1% (66/1297) and 1.9% (25/1297) in women < 35 years of age and 14.2% (99/695) and 1.6% (11/695) in women > or = 35 years of age, respectively. The detection efficiency of aneuploidy was 6/6 (100%) in women < 35 years and 11/12 (92%) in women > or = 35 years. Nuchal translucency measurement alone detected 57% (8/14) of cases of aneuploidy at a 5.8% (42/730) false-positive rate. Modelling with the age distribution of live births, a 5% false-positive rate resulted in Down's syndrome detection efficiency of 61% by biochemistry, 73% by nuchal translucency and 87% by combining both methods. The data in this study demonstrate that combined biochemical and ultrasound evaluation for Down's syndrome and other chromosomal abnormalities in the first trimester of pregnancy yield a detection capability that may exceed that of current second-trimester prenatal screening protocols. The potential for enhanced detection coupled to an earlier alert of fetal complications could represent a substantial advantage to both clinician and patient.

Adolescent↗
PubMed1996

Lack of evidence of permanent engraftment after in utero fetal stem cell transplantation in congenital hemoglobinopathies.

The use of fetal hematopoietic stem cells for in utero transplantation to create permanent hematochimerism represents a new concept in fetal therapy. In one fetus with alpha-thalassemia, one with sickle cell anemia, and one with beta-thalassemia, we have transplanted fetal liver cells obtained from legal abortions in gestational weeks 6-11. The fetus with alpha-thalassemia was transplanted twice during pregnancy, in the 15th (20.4 x 10(8) cells/kg) and in the 31st weeks of gestation (1.2 x 10(8) cells/kg), and is now two years of age. One fetus with sickle cell anemia received its transplant in the 13th week of gestation (16.7 x 10(8) cells/kg), and is now one year old. The fetus with beta-thalassemia was transplanted in 18th week (8.6 x 10(8) cells/kg), and is now three months old. Engraftment was evaluated by chromosomal analysis (sex chromosomes), red cell phenotyping, HLA class I and II typing, and PCR (polymerase chain reaction) for Y chromosome-specific sequences and DNA polymorphisms in cord and peripheral blood. The children with alpha- and beta-thalassemia underwent bone marrow aspirations at 3 and 7 months of age, respectively. In neither of these cases were we able to detect convincing evidence of stem cell engraftment. Thus, the administration of fetal stem cells to fetal recipients after the 12th week of gestation did not result in permanent hematochimerism. It remains to be determined whether the engraftment process can be promoted by earlier transplantations and/or higher cell doses.

Adult↗
PubMed1996

Changes in integrin and E-cadherin expression in neoplastic versus normal thyroid tissue.

UNLABELLED: BACK: The functional organization of polarized epithelia depends mostly on adhesion molecules belonging to the integrin and cadherin families. These molecules either recognize basement membrane components, such as laminins, or form intercellular junctions via homotypic interactions. Such tissue organization is often disrupted upon neoplastic transformation, and the resulting loss of functional polarization and cell cohesion might be a prerequisite for the invasive and metastatic behavior of carcinomas. PURPOSE: We studied modifications on thyroid adhesive mechanisms at various stages of neoplastic progression in terms of adhesion molecule expression, topography, and functional regulation by tyrosine kinases. Starting from this working hypothesis, we sought to identify one or more biological markers that would be suggestive of malignant transformation and poorer prognosis and that could be developed as a reliable indicator(s) in early diagnostic steps. METHODS: The study was carried out on both surgical samples and the corresponding fine-needle aspiration biopsy smears (numbers of specimens collected: 19 adenomas, seven follicular carcinomas, 13 papilary carcinomas, and 39 normal tissues). Immunohistochemistry of tissue sections and smears and immuno-precipitation and western blot analysis of protein extracts were done with a battery of monoclonal and polyclonal antibodies. Northern blotting was performed on RNA extracts from frozen tissue samples and use of an integrin subunit beta4 complementary DNA probe. RESULTS: Our findings can be summarized as follows: 1) In normal thyroid cells, the cooperative role of integrin alpha6beta4 and laminin 5/kalinin in hemidesmosome-mediated adhesion adhesion is missing, and recognition of the basal lamina occurs via integrin alpha3beta1 and laminin 1 and/or 2 (this pattern being maintained in adenomas but altered in carcinomas regardless of their histotype or differentiation grade); 2) only in carcinomas with clinical and/or histologic aggressiveness do neoexpression of integrin subunit beta4 and loss of laminin 2/merosin occur, indicating de novo assembly of integrin alpha6beta4; 3) pericellular redistribution and cytoskeletal disconnection of the E-cadherin-catenin complex occur; and 4) basal E-cadherin tyrosine phosphorylation decreases in carcinomas as compared with that in normal and adenomatous tissue. CONCLUSION: The malignant progression of thyroid tumors involves marked rearrangement of cell-basement membrane and cell-cell adhesion molecules and changes in their cytoskeleton linkage. These rearrangements are also easily and reproducibly detected on fine-needle aspiration biopsy smears. IMPLICATIONS: Immunodetection of adhesion molecules in sections and/or fine-needle smears may complement the toolbox of thyroid surgical pathologists; it may expand the possibilities of achieving a correct early diagnosis of thyroid tumors and of gaining some prognostic information on thyroid tumors.

Adenocarcinoma, Follicular↗
PubMed1996

Evidence of induced non-tolerance in HLA-identical twins with hemoglobinopathy after in utero fetal transplantation.

Fetus-to-fetus transplantation has been suggested for the treatment of hemoglobinopathies in utero. However, dissimilar results have to date been obtained by different groups. We describe a case in which fetus-to-fetus transplantation in HLA-identical twins was performed at the 19th week of gestation by infusion of 0.8 ml of fetal blood from normal to beta-thalassemia affected fetus with the main aim of inducing tolerance. No evidence of engraftment, determined by KM19 polymorphism, was present after 2 years of the procedure. Moreover, an alloreactive cytotoxic T lymphocyte precursor (CTLp) study of affected fetus vs donor and other different stimulators showed that immunization vs tolerance was the real effect of the procedure.

Adolescent↗
PubMed1996

[Tropisetron for the prevention of nausea and vomiting during chemotherapy: multicenter clinical study].

The antiemetic effect of tropisetron was studied in 97 cancer patients (67 men, 30 women) receiving cisplatin in doses of 75 mg/m2 or higher. On 279 chemotherapy cycles studied (max 6 per patient) 5 mg of tropisetron was administered once a day i.v on day 1 and p.o. on days 2 to 6. Efficacy preventing vomiting and nausea was measured in 24 hour period as: complete control O episodes, major control 1 to 2 episodes, minor control 3 to 4 episodes and no control 5 or more episodes. Satisfactory vomiting control (complete and major) was 69%, 63%, 82%, 88%, 96% and 96% in days 1 to 6 of cycle 1. Satisfactory nausea control (complete and major) for the same days was 70%, 66%, 72%, 85%, 92% and 97%. Similar data was obtained for the subsequent cycles. Complete vomiting control was obtained in 47%, 35%, 56%, 72%, 81% and 84% and for nausea in 42%, 39%, 48%, 64%, 81% and 87%. 19 patients presented adverse effects (19.6%). Only 2 headache episodes had a definite relation with the antiemetic drug. 12 patients discontinued the medication; 6 due to drug inefficacy, 2 to illness unrelated to the drug, 1 to lack of collaboration, and 3 due to other reasons. We conclude that tropisetron allows satisfactory control of acute and delayed vomiting in a high percentage of patients treated with high doses of cisplatin. The drug does not have significant secondary effects. Tropisetron administration in only one daily dose implies an evident advantage and a treatment cost reduction.

Adolescent↗
PubMed1995

Circadian variations of thyrotropin bioactivity in normal subjects and patients with primary hypothyroidism.

Circadian rhythm of TSH secretion is characterized by a pronounced nocturnal increment that is not followed by the expected rise of circulating thyroid hormone levels. These findings suggest that the nocturnal TSH surge may be constituted by molecules with reduced bioactivity. We, therefore, investigated TSH bioactivity (measured as cAMP accumulation in FRTL-5 cells) and its carbohydrate structure (by Concanavalin A affinity chromatography) in different blood pools taken during the day and night from seven normal subjects and from one patient with mild (mPH) and five with severe primary hypothyroidism (sPH). Patients with sPH were also studied during low dose L-T4 treatment. Cosinor analysis showed a significant TSH circadian rhythm in the control group and in L-T4-treated sPH patients. The nocturnal TSH surge was not followed by any increase in free thyroid hormone levels. In normal subjects, the daytime ratio of TSH bioactivity to immunoreactivity (TSH B/I) was higher than the nocturnal one [1.4 +/- 0.6 (+/- SD) vs. 1.1 +/- 0.6; P < 0.02]. The same pattern was observed in the only mPH patient (1.0 +/- 0.2 vs. 0.7 +/- 0.1; P < 0.01), but not in the sPH patients (0.8 +/- 0.3 vs. 0.7 +/- 0.1; P = 0.3). L-T4 administration to sPH patients caused the daytime TSH B/I to increase and restored the day/night difference in the TSH B/I (1.0 +/- 0.3 vs. 0.8 +/- 0.3; P < 0.02). Concanavalin A chromatography showed that a higher percentage of less mature forms of TSH are secreted during the night. These data indicate that TSH molecules secreted during the night are less bioactive and differently glycosylated than those circulating in the same individual during the day, thus explaining why thyroid hormone levels do not rise after the nocturnal TSH surge. In sPH patients, the TSH circadian rhythm is restored during L-T4 administration, and day/night differences in TSH B/I similar to those recorded in normal subjects are observed.

Adult↗
PubMed1994

Steroid biochemistry and categorization of breast cyst fluid: relation to breast cancer risk.

Patients bearing macrocysts of the breast are at higher risk of later developing cancer. The fluid filling the cysts (breast cysts fluid, BCF) contains unusual amounts of steroid conjugates, first androgen and estrogen sulfates. Measuring BCF cations (K+,Na+) allows categorization of cysts into two major subsets (type I and type II) that are associated with a different degree and/or turnover of apocrine metaplastic cells in the lining epithelium. Type I cysts (high K+/Na+ ratio) accumulate hugh amounts of dehydroepiandrosterone sulfate, estrone sulfate, androstane-3 alpha,17 beta-diol glucuronide, androsterone glucuronide and contain more testosterone and dihydrotestosterone than type II. Conversely, type II cysts (low K+/Na+ ratio) contain more progesterone and pregnenolone. A cohort study was started in 1983 at the Cancer Prevention Center, Ravenna, Italy, with the aim of evaluating the relationships between the biochemistry of BCF and the incidence of breast cancer in women with gross cystic disease (GCD) of the breast. The bimodal distribution of the cationic pattern has been confirmed from data obtained in 798 patients aspirated. The risk of cyst relapse was significantly higher among women with type I cysts or with multiple cysts at presentation. Twelve incident cases of breast cancer have been diagnosed among women whose BCF was categorized. Eleven out of 12 cases had type I or multiple cysts. The cumulative incidence of breast cancer among patients bearing type I cysts was 2.5%. We conclude that women with GCD bearing type I cysts have an increased breast cancer risk when compared with the counterpart bearing type II cysts or the general population.

Adult↗
PubMed1994

Chronic ethanol feeding increases apoptosis and cell proliferation in rat liver.

The present study was conducted to evaluate if the increased rate of apoptosis previously reported in the liver of ethanol-treated rats was accompanied by increased cell renewal. A quantitative analysis of apoptosis was performed in rats fed an ethanol-containing liquid diet for 5 weeks. S-phase cells were demonstrated by immunohistochemistry, using the Bromodeoxyuridine/anti-Bromodeoxyuridine method. In ethanol-fed rats apoptosis was five times greater than in pair-fed controls. Bromodeoxyuridine-labelled hepatocytes increased from 0.07 +/- 0.009% in controls to 0.17 +/- 0.013% (p < 0.001) and Bromodeoxyuridine-labelled lipocytes (desmin-positive sinusoidal cells) increased from 3.43 +/- 0.28% to 6.60 +/- 1.04% (p < 0.001). The lobular distribution of labelled cells was modified with a shift towards the perivenular areas. The results of this study suggest that the replacement of liver cells lost by ethanol-induced apoptosis is not impaired in intact (non-operated) animals. The impaired regeneration following partial hepatectomy reported in ethanol-fed rats is possibly due to differences in the extent of parenchymal loss, to altered relationships between hepatocytes and blood supply and to the modalities of regeneration involved.

Alcoholism↗
PubMed1994

Chemotherapy with dacarbazine and 5-fluorouracil in advanced medullary thyroid cancer.

BACKGROUND: Experience with chemotherapeutic agents in the management of advanced medullary thyroid carcinoma (MTC) is limited and controversial. However, since MTC is a neuroendocrine neoplasm, we considered the possibility that cytotoxic drugs previously used in the treatment of these tumours could also have activity in MTC. PATIENTS AND METHODS: Five patients (4 females and 1 male, aged 22-71 years) with locally advanced or metastatic MTC received 5 day intravenous courses of dacarbazine (DTIC) (250 mg/sqm) and 12 hour infusion 5-fluorouracil (450 mg/sqm), given every 4 weeks. Six cycles were administered to 4 patients and four to 1 patient. RESULTS: Three partial responses lasting 9, 10+ and 8+ months were observed; one patient had stable disease and one progressive disease. Toxicity was acceptable with grade I thrombocytopenia and grade II leukopenia occurring in one patient, and grade II nausea and vomiting in four patients. CONCLUSIONS: In our experience, treatment of advanced thyroid carcinoma with DTIC and 5-FU appeared to have significant activity and was well tolerated.

Adult↗