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S Milani

Publications and source records attributed to S Milani.

At least 55 records · Page 3Linked to original sources
PubMed1998

Increased expression of monocyte chemotactic protein-1 during active hepatic fibrogenesis: correlation with monocyte infiltration.

Monocyte chemotactic protein (MCP)-1 is a chemoattractant and activator for circulating monocytes and T lymphocytes. We investigated MCP-1 protein and gene expression during chronic liver disease at different stages, using immunohistochemistry and in situ hybridization, respectively. In normal liver, a modest expression of MCP-1 was confined to few peri-sinusoidal cells and to bile duct epithelial cells. During chronic hepatitis, MCP-1 immunostaining and gene expression were evident in the inflammatory infiltrate of the portal tract. In tissue from patients with active cirrhosis, MCP-1 expression was clearly up-regulated and was present in the portal tract, in the epithelial cells of regenerating bile ducts, and in the active septa surrounding regenerating nodules. A combination of in situ hybridization for MCP-1 and immunohistochemistry showed that activated stellate cells and monocyte/macrophages contribute to MCP-1 expression in vivo together with bile duct epithelial cells. Comparison of serial sections of liver biopsies from patients with various degrees of necro-inflammatory activity showed that infiltration of the portal tracts with monocytes/macrophages is directly correlated with the expression of MCP-1. These data expand previous in vitro studies showing that secretion of MCP-1 may contribute to the formation and maintenance of the inflammatory infiltrate observed during chronic liver disease.

Adult↗
PubMed1997

Heterogeneity of liver cells expressing procollagen types I and IV in vivo.

The extracellular matrix of fibrotic liver is predominantly produced by mesenchymal cells, the in vivo phenotype of which is poorly defined. We report on the application of combined immunohistology and in situ hybridization with [35S]-labeled alpha 1(I) and alpha 1(IV) procollagen RNA probes. In CCl4-treated rats, all alpha 1(I) procollagen-producing cells were vimentin positive but cytokeratin negative; over 90% expressed desmin, a marker of rat liver stellate cells. alpha 1(I) Procollagen-expressing, desmin-negative cells were confined to portal tract and perivascular stroma. Similarly, alpha 1(I) procollagen gene transcripts were, in all instances, colocalized with vimentin in human liver. In fibrotic specimens, over 70% of these cells expressed alpha-actin. Antibodies against epithelial, endothelial, and Kupffer cells, granulocytes, and lymphocytes did not react with alpha 1(I) procollagen RNA-expressing cells. Localization, morphology, and immunophenotype of alpha 1(I) procollagen-expressing cells indicated stellate cells and portal/vascular fibroblasts, but not epithelial cells, to be sources of hepatic interstitial collagen. However, most alpha 1(IV)-expressing human liver cells were identified as endothelial cells, the remaining cells were (myo-)fibroblastic and bile duct epithelial cells, but not hepatocytes. This indicates synthesis of procollagen type IV from both sides of the basement membrane and suggests an active participation of endothelial cells in the process of sinusoidal capillarization.

Adult↗
PubMed1997

In situ detection of matrix metalloproteinase-2 (MMP2) and the metalloproteinase inhibitor TIMP2 transcripts in human primary hepatocellular carcinoma and in liver metastasis.

BACKGROUND/AIMS: Metalloproteinase (MMP)-2 and the metalloproteinase inhibitor TIMP2, play a critical role in tumor invasion. We have investigated the cellular sources of MMP2 and TIMP2 in primary and secondary human liver cancers. METHODS: Using in situ hybridization and zymography, we analyzed surgical biopsies from matching pairs of tumoral and non-tumoral liver from six hepatocellular carcinomas and seven liver metastases and from four liver donors. The cellular sources of MMP2 and TIMP2 were further characterized using an anti-alpha-smooth muscle actin antibody on contiguous sections. RESULTS: In hepatocellular carcinoma and liver metastases, in situ hybridization showed that MMP2 and TIMP2 mRNA were expressed by anti-alpha-smooth muscle actin-positive cells at the invasive front. Slender fibroblasts embedded in a denser matrix were MMP2(+)/TIMP2(+)/anti-alpha-smooth muscle actin(+). Intratumor microvessels showed a strong labeling for MMP2 but weak for TIMP2 mRNA. In contrast, the endothelial lining of the central veins was MMP2(+)/TIMP2(+) in non-tumoral areas with signs of blood-flow obstruction. In control livers, MMP2 and TIMP2 mRNA distribution was restricted to fibroblasts and endothelial cells within portal tracts and scattered sinusoidal cells. Direct zymography of samples comprising the invasive front revealed variable amounts of both proMMP2 and its active form in hepatocellular carcinoma, whereas strong bands corresponding to both active and latent forms of MMP2 were detected in liver metastases. CONCLUSIONS: The striking density of MMP2(+)/TIMP2(+)/anti-alphaSM(+) stellate-shaped cells in the perisinusoidal space adjacent to liver tumors suggests that hepatic stellate cells, upon differentiation to myofibroblasts, may contribute to the dissemination of liver metastases through the sinusoidal network.

Actins↗
PubMed1997

The long-term efficacy and safety of two different corticosteroids in chronic sarcoidosis.

Deflazacort (DFZ) is claimed to have fewer adverse bone effects than prednisone (PDN) at doses with equivalent anti-inflammatory activity (5 mg PDN = 6 mg DFZ). However, its safety over the long-term has never been tested in a controlled trial. The aim of the present study was to assess prospectively the safety and efficacy of DFZ compared with PDN in previously untreated patients with chronic, histologically proven sarcoidosis needing long-term (> or = 2 yr) corticosteroid therapy. Thirty-six patients were treated with PDN for 32 +/- 18 months and 36 patients were treated with DFZ for 42 +/- 18 months, and followed-up with periodic chest X-ray, 67Gallium lung scan, angiotensin converting enzyme (ACE), serum and urinary calcium levels, spirometry, alveolar diffusion (DLCO) arterial oxygen tension (PaO2), bone mineral content (BMC) (by computed tomography), and a complete biochemical and haematological profile. The two groups were similar as regards sex, age, pulmonary and extrapulmonary involvement, parameters of activity and impairment, and initial BMC. Daily starting doses were 23.2 +/- 11.4 mg DFZ and 22.3 +/- 6.9 mg PDN. One year of trial was completed by 69 patients, 2 yr by 59 patients, 3 yr by 46 patients and 4 yr by 24 patients. Some patients were followed-up for 5-7 yr. The mean daily dose over the whole period was 15 +/- 10 mg DFZ and 10 +/- 6 PDN, starting from 21 +/- 9 and 15 +/- 8 mg in the first year, and progressively declining to a mean of 9 +/- 6 mg in both groups in the fourth year. Chest X-ray, 67Ga score, ACE and forced vital capacity improved significantly in both groups. Urine total calcium improved significantly in the PDN group (345 +/- 27 to 186 +/- 47; P < 0.05) with a similar but non-significant pattern in the DFZ group (270 +/- 28 to 207 +/- 39). Non-significant improvements were observed in DLCO, PaO2 and forced expiratory volume in 1 s in both groups. Drug-related adverse events were more frequent in the PDN group, causing discontinuation of the drug in four PDN patients. Body weight increased mainly in the PDN group [69.9 +/- 0.4 to 73.6 +/- 0.8 kg vs 70.1 +/- 0.4 to 70.0 +/- 0.6 kg in the DFZ group (P < 0.01)]. Bone mineral content dropped under the fracture threshold in most PDN patients, who thus appeared at higher risk for fractures. In fact, six atraumatic skeletal fractures were observed in this group but only one in the DFZ group. Two further patients in the DFZ group and eight in the PDN group were obliged to start corrective measures for bone loss and/or bone pain. At the end of the study, 21 patients (12 DFZ, nine PDN) no longer needed corticosteroids, and the others were taking a maintenance daily dose that controlled the disease adequately. In conclusion, DFZ appeared as effective as PDN in the long-term treatment of chronic sarcoidosis, and it may have fewer side-effects, especially on bone.

Adult↗
PubMed1997

Expression of epidermal growth factor, transforming growth factor-alpha and their receptor in the human oesophagus.

Increasing evidence indicates that epidermal growth factor and transforming growth factor-alpha are involved in the maintenance of oesophageal mucosal integrity. However, their cellular origin and the exact localization of their receptor in the oesophagus are still unclear. Therefore, we examined the expression of the two growth factors and their shared receptor in the normal human oesophagus at both mRNA and protein level, by immunohistochemistry, in situ hybridization and reverse transcription-polymerase chain reaction. In addition to being expressed in the proliferative compartment of the oesophageal epithelium, the receptor was found in a variety of cells, including smooth muscle cells, submucosal gland cells and the epithelium lining their ducts. Immunohistochemically, the pattern of distribution of epidermal growth factor paralleled that of its receptor. In situ hybridization demonstrated epidermal growth factor mRNA expression in the oesophageal epithelium and submucosal glands. Additionally, amplified transcripts of predicted size were detected by reverse transcription-polymerase chain reaction, thus confirming that authentic transcripts of the growth factor exist in the normal human oesophagus. Transforming growth factor-alpha mRNA and protein expression, while similar to that of epidermal growth factor, predominated in the more differentiated cell layers of the stratified squamous epithelium. These results demonstrate that the normal oesophagus can synthesize both growth factors. Moreover, the peculiar distribution of these peptides and the concomitant expression of their receptor in multiple cell types suggest that the two growth factors may exert diverse physiological functions in the oesophagus and participate in defence and reparative events following mucosal injury.

Adult↗
PubMed1997

Variation of bone age progression in healthy children.

Bone age assessments were related to auxological variables in 407 Italian boys, between 7 and 12 years of age, in order to elucidate the factors that affect the rate of skeletal maturation and to examine the possibility of using measures of skeletal maturation of evaluate individual patients. Using the radius-ulna-short bones (RUS) method of assessment, bone age velocity was greater in the Italian boys than for the UK reference standards, although there was considerable interindividual dispersion around the mean. Bone age velocity and height velocity were poorly correlated, and there was little correlation between skeletal and pubertal maturation. There was a slight positive correlation between bone age velocity and height SDS and between bone age velocity and body mass index. Bone age estimations using RUS were greater than those obtained using the carpus. In conclusion, the marked interindividual deviation in measured bone ages makes it difficult to relate data on an individual basis to other measures of growth and maturation

Age Determination by Skeleton↗
PubMed1997

Tissue inhibitor of metalloproteinase-1 and -2 RNA expression in rat and human liver fibrosis.

The remodeling of extracellular matrix during chronic liver disease may partially be attributed to altered activity of matrix metalloproteinases and their tissue inhibitors (TIMPs). Expression of TIMP-1 and -2 was studied by in situ hybridization combined with immunohistochemistry in rat (acute and chronic carbon tetrachloride intoxication and secondary biliary fibrosis) and human livers and on isolated rat hepatic stellate cells. TIMP-1 and -2 transcripts appeared in rat livers within 1 to 3 hours after intoxication, pointing to a role in the protection against accidental activation of matrix metalloproteinases, and were present at high levels in all fibrotic rat and human livers predominantly in stellate cells. TIMP-2 RNA distribution largely matched with previously reported patterns of matrix metalloproteinase-2 (72-kd gelatinase) expression, suggesting generation of a TIMP-2/matrix metalloproteinase-2 complex (large inhibitor of metalloproteinases). Isolated stellate cells expressed TIMP-1 and -2 RNA. Addition of transforming growth factor-beta 1 enhanced TIMP-1 and matrix metalloproteinase-2 RNA levels in vitro, whereas TIMP-2-specific signals were reduced, likely to result in a stoichiometric excess of matrix-metalloproteinase-2 over TIMP-2. In the context of previous demonstrations of transforming growth factor-beta 1 and matrix metalloproteinase-2 in vivo, these patterns suggest an intrahepatic environment permitting only limited matrix degradation, ultimately resulting in redistribution of extracellular matrix with relative accumulation of collagen type 1.

Adult↗
PubMed1996

Expression of epidermal growth factor and its receptor in normal and diseased human kidney: an immunohistochemical and in situ hybridization study.

The kidney is one of the major sites of EGF production and there it seems to play several biological functions, such as modulation of cell growth, renal repair following injury, regulation of cellular metabolism and glomerular haemodinamics. The present study was first aimed at localizing EGF and its receptor (R) in normal human kidney by immunohistochemical and in situ hybridization techniques. Then, the distribution of the growth factor and its R was explored in biopsy specimens from eight patients with acute tubulointerstitial damage. In the normal human kidney, both EGF immunoreactivity and EGF mRNA were localized in tubular profiles corresponding to Henle's loop and, although to a lesser intensity, to distal convoluted tubule. EGF immunostaining was remarkable mainly at the apical surface of tubular cells. EGF-R protein expression was detected in glomerular endothelial cells, in peritubular capillaries and arteriolar walls, as well as along the thick ascending limb of Henle's lop and distal convoluted tubule, where it colocalized with Tamm-Horsfall protein. Immunohistochemical analysis of tubular profiles revealed that EGF-R was located especially along the basolateral membrane of tubular cells and within the basal part of cytoplasm. Endogenous alkaline phosphatase and CHIP28 positive tubules did not show any signal for EGF and its receptor. Kidneys with acute tubulointerstitial injury exhibited a dramatic decrease of EGF expression, whereas EGF-R showed only minor modifications. Interestingly, EGF-R was localized to both apical and antiluminal membranes of positive tubular cells. It is concluded that EGF-EGF receptor loop may be relevant in the pathogenesis of acute tubulointerstitial damage and recovery from tubular injury, while its role in the physiological renewal of the urothelium remains speculative.

Biopsy↗
PubMed1996

Endothelin 1 is overexpressed in human cirrhotic liver and exerts multiple effects on activated hepatic stellate cells.

BACKGROUND & AIMS: Endothelin (ET) 1 could be involved in the regulation of hepatic microcirculation and in the development of portal hypertension. The expression and distribution of ET-1 in normal and cirrhotic liver tissue and its effects on hepatic stellate cells (HSCs), liver-specific pericytes, were investigated. METHODS: ET-1 expression in liver tissue was analyzed using in situ hybridization and immunohistochemistry. Secretion of ET-1 by HSC was evaluated by radioimmunoassay. Changes in intracellular Ca2+ concentration and cell contraction were studied using digital video imaging. Specific binding of ET-1 was evaluated using self- and cross-displacement curves. RESULTS: ET-1 expression was markedly enhanced in cirrhotic liver tissue, where activated HSCs were shown to be major sites of ET-1 synthesis, as confirmed by studies performed on cultured human HSC. ET-1 exerted several biological actions on HSC, including mitogenicity, activation of mitogen-activated protein kinase, and a rapid increase in intracellular Ca2+ coupled with reversible cell contraction. All these effects appeared to be mediated by ETA receptors. Finally, the relative prevalence of ETA and ETB binding sites changed with the progressive phenotypical modulation of HSC. CONCLUSIONS: ET-1 may act as a paracrine and autocrine factor for activated HSC and contribute to the increased resistance to portal flow in cirrhotic liver.

Adipocytes↗
PubMed1996

Fetal growth velocity: kinetic, clinical, and biological aspects.

With the aim of determining fetal growth kinetics, prenatal data were analysed which had been longitudinally collected in the framework of a perinatal growth survey. The sample comprised 238 singleton normal pregnancies, selected in Genoa and Turin (between 1987 and 1990), and repeatedly assessed by ultrasound scans (five to nine per pregnancy). Five morphometric traits were considered: BPD (biparietal diameter), OFD (occipitofrontal diameter), HC (head circumference), FDL (femur diaphysis length) and AC (abdomen circumference). Growth rate seemed to increase in the early part of the second trimester, and decrease subsequently: velocity peaks were steeper and earlier for head diameters and circumference (about 18 weeks) than for femur length (20 weeks) and abdomen circumference (22 weeks). Velocity standards were traced using a longitudinal two-stage linear model: this ensures unbiased description of the shape of the growth curve, even when growth kinetics are asynchronous, and efficient estimation of the outer centiles--the most useful for diagnostic purposes.

Abdomen↗
PubMed1996

Main problems associated with bone age and maturity evaluation.

In scientific papers, skeletal maturation-expressed as bone maturity scores or bone age-is often used as a quantifiable variable similar to height or weight. This paper discusses whether this approach is appropriate. The questions addressed are whether skeletal maturation can be measured on a quantitative scale, whether its use is appropriate in computing, and what the 'numbers' used represent. Reference will be made mainly to the Tanner-Whitehouse method, which, in the opinion of the authors, has been the most reliable method of assessment to date. Many of the remarks made in this paper may be extended to other methods of assessment, and have been stressed by Tanner himself. The authors are aware that, in the future, some of the remarks could be made redundant by the development of more detailed definitions of bone maturation. This is becoming feasible with the advent of expert systems for the automatic recognition of different stages of bone maturation.

Adolescent↗
PubMed1996

Epidermal growth factor, epidermal growth factor receptor, and transforming growth factor-alpha in human hyperplastic prostate tissue: expression and cellular localization.

It is widely accepted that polypeptide growth factors are involved in the growth and development of normal and neoplastic human prostate. It has been previously reported that epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) receptors are present in the human hyperplastic prostate tissue (BPH). To add information on the mechanism of action of EGF and transforming growth factor-alpha (TGF alpha), a peptide correlated to EGF, and the EGF receptor (EGF-R) in the human prostate, we studied the expression and cellular localization of messenger ribonucleic acid (RNA) encoding EGF, EGF-R, and TGF alpha in BPH tissue. Reverse transcriptase-PCR of total RNA extracted from BPH tissues documented the presence of specific transcripts for EGF, EGF-R, and TGF alpha. In situ hybridization with specific RNA probes synthesized from the respective complementary DNA demonstrated that EGF, EGF-R, and TGF alpha messenger RNAs were mainly localized in the epithelial cells. Immunprecipitation and Western blot analysis showed that BPH tissue contained the corresponding proteins, EGF and TGF alpha. Our findings provide additional support for the idea that EGF and TGF alpha may be considered specialized symbols in the language of cell-cell interactions and for the hypothesis that in the human prostate they seem to act in an autocrine fashion.

Epidermal Growth Factor↗
PubMed1996

Expression of endothelin-1 gene and protein in human granulosa cells.

Previous studies in animal models indicated an autocrine/paracrine action of endothelin-1 (ET-1) in the ovary. We now report evidence on the presence of ET-1 in human ovary during reproductive life. Immunohistochemical and in situ hybridization studies demonstrated a positive signal into cytoplasm of granulosa cells (GC) of follicles at different growth stages. The concentration of ET-1-like immunoreactivity (ET-1-LI) was also measured by a specific RIA in human follicular fluid (FF). FF samples were obtained from women in an in vitro fertilization program undergoing gonadotropin stimulation (group A; n = 24) or no treatment (group B; n = 7). The mean (+/-SD) ET-1-LI FF level in group A (4.85 +/- 2.06 pg/mL) was significantly higher than that in group B (1.29 +/- 0.43 pg/mL; P < 0.01), whereas the corresponding mean plasma levels were not significantly different and were not correlated to respective FF values. Our results indicate for the first time the presence of ET-1 and its messenger ribonucleic acid in the GC of the human ovary. The higher ET-1-LI levels found in the FF from women undergoing gonadotropin treatment suggest a modulation by gonadotropins and/or ovarian steroids of ET-1 production by GC.

Adult↗
PubMed1996

Hypertension may be transplanted with the kidney in humans: a long-term historical prospective follow-up of recipients grafted with kidneys coming from donors with or without hypertension in their families.

In several genetic hypertensive rat strains, transplantation studies have established that the kidney carries at least a portion of the genetic message for hypertension. In man it has, of course, been more difficult to obtain clearcut results. This historical prospective observational study, double-blinded for knowledge of donors' and recipients' family history for hypertension, concerns 85 transplanted patients, not treated with cyclosporine and with stable renal function, followed up for an average of 8 yr. Both the donors' and the recipients' families were carefully characterized for presence or absence of hypertension. After transplantation, in recipients without hypertension in their own families, a kidney coming from a "hypertensive" family determines less withdrawal and more introduction of antihypertensive therapy (AHT) than a kidney from a "normotensive" family (odds ratio for AHT introduction 5.0, confidence interval, 1.4 to 17.8; P = 0.017). In recipients with familial hypertension, the origin of the kidney does not influence the prevalence of hypertension after transplantation. More detailed analyses show that, in recipients without familial hypertension, the transplantation of a "hypertensive" kidney determines a tenfold larger increase in the requirement of antihypertensive therapy than the transplantation of a "normotensive" kidney, to obtain a similar blood pressure control (P = 0.003). This results is confirmed by the analysis of time-profile trends for antihypertensive therapy, adjusted for missing data, in the most clinically stable period (2nd to 10th yr after transplantation). The transmission of familial hypertension with the kidney is thus seen only in recipients coming from "normotensive" families, because a familial tendency for hypertension blunts the effect of receiving a "hypertensive" kidney.

Adult↗
PubMed1996

Expression of platelet-derived growth factor and its receptors in normal human liver and during active hepatic fibrogenesis.

Expression of platelet-derived growth factor (PDGF) and its receptor (R) subunits was evaluated in normal human liver and in cirrhotic liver tissue by in situ hybridization and immunohistochemistry. In normal liver, PDGF and PDGF-R subunit expression was limited to a few mesenchymal cells of the portal tract stroma and vessels. In cirrhotic liver, PDGF-A and -B chain mRNA expression was markedly increased and was co-distributed with immunoreactivity for PDGF-AA and -BB in infiltrating inflammatory cells and along vascular structures within fibrous septa. These aspects were paralleled by a marked overexpression of PDGF-R alpha- and beta-subunit mRNAs and of the relative immunoreactivities in a wide range of mesenchymal cells in fibrous septa and in perisinusoidal alpha-smooth-muscle-actin-positive cells. In general expression and distribution of PDGF-R subunits appeared to be related to the activation of different mesenchymal cell types involved in the fibroproliferative process. Therefore, we evaluated the expression of PDGF-R subunits in liver tissue specimens with increasing degrees of necroinflammatory activity. The results of this additional study confirmed that expression of PDGF-R subunits is highly correlated with the severity of histological lesions and collagen deposition. Our results, providing evidence for a functional involvement of PDGF/PDGF-R in liver fibrogenesis, greatly support the results of previous in vitro studies and direct attention toward pharmacological strategies able to affect the series of signaling events arising from the autophosphorylation of PDGF-R subunits.

Chronic Disease↗
PubMed1995

Role of epidermal growth factor in peptic ulcer healing.

In recent years, increasing interest has been focused on peptide growth factors, and impressive progress has been made in the understanding of their role in tumor development and progression. However, evidence is mounting that peptides such as epidermal growth factor and transforming growth factor-alpha may be of much more physiological than pathological importance. This brief article is intended to give a rapid overview of the available data supporting a role for epidermal growth factor and its human homologue urogastrone in peptic ulcer healing.

Animals↗
PubMed1995

Duodenal ferritin synthesis in genetic hemochromatosis.

BACKGROUND/AIMS: The molecular defect of genetic hemochromatosis (GH) is unknown. It is believed that low expression of duodenal ferritin in GH is caused by tissue or cell specific defect of ferritin synthesis. Our study was designed to ascertain whether the control of duodenal ferritin synthesis in GH was defective. METHODS: Expression at the single cell level of H and L ferritin messenger RNAs and protein and activity of the iron regulatory factor, which controls the translation of ferritin messenger RNA, were assessed in 43 duodenal biopsy specimens from individuals with GH, secondary hemochromatosis (SH), anemia, or normal iron balance. RESULTS: Signal for ferritin H and L subunit messenger RNAs was detected in both absorptive and nonabsorptive cells by in situ hybridization, but in 10 of 14 patients with untreated GH, the signal was lower than in patients with SH or normal subjects. However, immunostaining for ferritin protein documented a diffuse/cytoplasmic pattern, whereas a supranuclear/granular staining was found in normal subjects or patients with SH. The spontaneous activity of duodenal iron regulatory factor was consistently higher in patients with GH than in normal subjects or subjects with anemia or SH. CONCLUSIONS: In patients with GH, ferritin gene transcription is preserved in both absorptive and nonabsorptive intestinal cells. Low accumulation of ferritin is not caused by a defective control of ferritin synthesis but by low expression of ferritin messenger RNA and sustained activity of iron regulatory factor.

Adolescent↗