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M Trovato

Publications and source records attributed to M Trovato.

At least 19 recordsLinked to original sources
PubMed2006

Immunoexpression of the CD30 ligand/CD30 and IL-6/IL-6R signals in thyroid autoimmune diseases.

To elucidate the role of Th2 cytokines in autoimmune thyroid diseases, we have studied by immunohistochemistry the expression of two Th2 ligand/receptor systems (CD30-L/CD30 and IL-6/IL-6R) in goitrous Graves' disease (GD) and Hashimoto's thyroiditis (HT). A total number of 50 nodular goiters (NG), including 10 GD showing a lymphoid aggregate grade I, 30 HT 8 of which had a lymphoid aggregate of grade I, 12 of grade II and 10 grade III, and 10 colloid goiters have been evaluated. In addition, 5 normal thyroids were included in the study as controls. Reactivity of ligand and cognate receptor of both CD30-L/CD30 and IL-6/IL-6R pathways was observed in a greater proportion of GD, compared to HT (P<0.005). In HT, the expression of CD30-L/CD30 system was detected more frequently than IL-6/IL-6R (P<0.05) and showed an inverse correlation with the grade of lymphoid aggregate, whereas IL-6/IL-6R correlated positively with lymphocyte infiltration (P<0.05). Based on our results concerning a dominance of Th2 cytokines in GD, we postulate that CD30-L/CD30 and IL-6/IL-6R systems could play a major role in the pathogenesis of GD. However, the expression of CD30L/CD30 and IL-6/IL-6R in HT suggests that Th2 mechanisms are involved also in tissue damage of HT. The two systems could contribute to drive the autoimmune response skewing toward a Th2 phenotype and this appears to be correlated with the lymphoid aggregate grade.

Adult↗
PubMed2005

Nosocomial infections in colo-rectal surgery of the old patient.

Every surgical act, especially in geriatric age, can be a relevant moment in the onset of nosocomial infections. This has a peculiar aspect in patient who undergo colo-rectal surgery, both in election and especially in emergency, in which the simple opening of intestines always involves a minimal contamination. In order to reduce the incidence of infections, and therefore the septic complications of this surgery, it is necessary to pay attention to the preparation of the surgical equipe, of the operating room, of the surgical instruments and, in election, to the careful preparation of the patient through a careful evaluation of the possible bio-umoral alterations, in order to correct them. The results of our experience allow us to say that the prevention of post-operatory sepsis find its main moment in the careful evaluation and eventual correction of the nutritional status, in the stimulation of the immune system, in the antibiotic prophylaxis both parenteral and topical, and, last but not least, in a correct surgical technique. All this is particularly important for patients affected by colo-rectal neoplastic and inflammatory diseases, for which the intestinal bacteria, more virulent in weak and fragile patients, often represent the source of contamination that can start a sepsis and then assume an important part in determining the final result of surgery.

Aged↗
PubMed2003

Distinctive expression of STAT3 in papillary thyroid carcinomas and a subset of follicular adenomas.

Hepatocyte growth factor (HGF), HGF receptor (c-met) and the interleukin 6 (IL-6) are expressed in thyroid nodules. In extra-thyroidal tissues, the HGF/c-met and IL-6/IL-6 receptor (IL-6R) systems activate STAT3, a member of the signal transducers and activators of transcription (STATs) family. To evaluate whether either system utilizes STAT3 in thyroid nodules, we examined the immunohistochemical expression of HGF, c-met, IL-6, IL-6R, STAT3 in 6 normal thyroids and in 68 thyroid nodules. STAT3 expression was observed in 12/12 (100%) papillary thyroid carcinomas (PTC) but in none of the follicular tumors. Among benign thyroid nodules, only 2/10 (20%) follicular adenomas (FA) were STAT3+. All these 14 STAT3+ cases expressed both HGF and c-met, but only 5 PTC co-expressed IL-6 and IL-6R and the 2 FA were IL-6+ but IL-6R-. The remaining 8 FA were all HGF/c-met-, but IL-6+; of these 8, only 2 were also IL-6R+. In conclusion, in thyroid nodules STAT3 is expressed only in PTC and a number of FA. Since these cases are consistently HGF+/c-met+ and only one-third of them co-express IL-6/IL-6R, STAT3 expression correlates with the HGF/c-met expression, not with the IL-6/IL-6R expression. The 100% rate of expression of the HGF/c-met/STAT3 signaling in PTC could be relevant for the establishment of the papillary phenotype. Because of the communeness of a HGF/c-met/STAT3 pattern between all PTC and a subset of FA, we speculate that a fraction of FA may progress to PTC.

Adenoma↗
PubMed2002

Co-expression of interleukin-6 (IL-6) and interleukin-6 receptor (IL-6R) in thyroid nodules is associated with co-expression of CD30 ligand/CD30 receptor.

Data on the expression of interleukin 6 (IL-6)/interleukin 6 receptor (IL-6R) in thyroid nodules is scarce. Based on our recent data of CD30 ligand (CD30L)/CD30 receptor (CD30) in these nodules and on the knowledge that this signal stimulates IL-6 production in non-thyroid neoplasms, we wanted to evaluate the immunocytochemical expression of these 2 ligand/receptor systems in a large archival series of paraffin-embedded specimens. These specimens included 6 normal thyroids and 130 thyroid nodules. Co-expression of IL-6 and IL-6R in the epithelial (follicular) cells was observed solely in CD30L/CD30 positive nodules: 5/15 (33%) oncocytic adenomas; 6/30 (20%) follicular adenomas which belonged to 2 variants (4/4 microfollicular toxic and 2/2 hyalinizing trabecular); 9/30 (30%) papillary thyroid cancers (PTC), all belonging to the conventional variant. In PTC the proportion of tumor epithelial cells that were IL6 positive was inversely correlated with the pTNM staging (r=-0.549, p=0.01). All 15 follicular cancers (FTC), all 6 anaplastic cancers (ATC) were IL-6/lL-6R negative; 14/15 FTC and 5/6 ATC were CD30L/CD30 negative. In another oncocytic adenoma, another 4 conventional PTC and another 7 non-conventional PTC CD30L/CD30 expression was associated to expression of IL-6 only. IL-6 staining associated to absent expression of CD30L and CD30 was observed in 7 follicular adenomas (all belonging to variants different from toxic and hyalinizing trabecular), 2 oncocytic adenomas, 5 of the 30 colloid nodules and 2 normal thyroids. Of the 6 tumors arising from the parafollicular C cells (medullary thyroid cancer, MTC), all 3 that had metastasized were CD30L/CD30/IL-6 positive and IL-6R negative; only IL-6 expression was lost in both the local and distant metastases. This finding matched the loss of IL-6 expression in one PTC metastasis. All 3 non-metastasized MTC were IL-6/IL-6R negative, and 1/3 was CD30L positive/CD30 negative. We conclude that only in a subset of both benign and malignant thyroid nodules the IL-6/IL-6R signal could be induced by the CD30L/CD30. IL-6 expression is related with aggressiveness in both PTC and MTC. In the normal thyroid tissue, colloid nodules, and another subset of benign and malignant thyroid nodules, IL-6 expression is under control of signals other than CD30L/CD30.

Adenocarcinoma, Follicular↗
PubMed2002

Immunoexpression of the hepatocyte growth factor (HGF), HGF-receptor (c-met) and STAT3 on placental tissues from malformed fetuses.

To characterize the possible relationship between the expression of the HGF/HGF-R system with transcription factor STAT3, responsible for morphogenetic response of HGF stimulation, and the embryonic development alterations, we investigated, by immunohistochemistry, the expression of HGF, c-met and STAT3 in 9 placentas from malformed fetuses and 9 control placentas from non-malformed fetuses. The major and distinct patterns of expression characterizing the placentas from malformed fetuses were a higher percentage mean of stromal cells stained for HGF, c-met and STAT3 antibodies (60%, 66% and 54%, respectively on fibroblast cells and 44%, 57% and 42%, respectively on myofibroblast cells) and a lower percentage mean of cytotrophoblast cells stained for the same antibodies (2%, 2% and 1%, respectively), than in control placentas. In fact, in this latter group, the stromal fibroblast cells were stained in a percentage mean of 27%, 22% and 7%, respectively; the stromal myofibroblast cells in a percentage mean of 5%, 6% and 2%, respectively and the cytotrophoblast cells in a percentage mean of 25%, 34% and 18%, respectively. The expression of each antibody on stromal cells in both groups suggests an alternative role of the HGF/HGF-R system activating the via STAT3 transdution and operating on placental tissues, overall in organogenesis alteration conditions. This immunohistochemical approach could be used in the diagnostic practice of pathologists on chorionic villi biopsy when genetic alterations are absent and ultrasound aspects are doubtful for malformations.

DNA-Binding Proteins↗
PubMed2001

The plant oncogene rolD encodes a functional ornithine cyclodeaminase.

The plant oncogene rolD stimulates the reproductive phase transition in plants. We define here the function of its gene product. We show that the RolD protein bears sequence homology with ornithine cyclodeaminase, an uncommon enzyme of specialized-niche eubacteria and archaea that catalyzes the unusual NAD(+)-dependent conversion of ornithine to proline. To confirm the prediction of the bioinformatic analysis, the RolD protein was expressed in Escherichia coli and purified. An ornithine-dependent NAD(+) reduction that can be ascribed only to ornithine cyclodeaminase (OCD) activity was detected both in bacterial extracts containing RolD and in assays on the purified RolD protein. Furthermore, OCD activity was observed in soluble extracts from plants overexpressing rolD. The role of rolD in plant pathogenesis and its effect on plant reproductive development are discussed in light of the newly demonstrated enzymatic activity of its gene product.

Amino Acid Sequence↗
PubMed2001

Expression of CD30 ligand and CD30 receptor in normal thyroid and benign and malignant thyroid nodules.

Because the CD30 ligand (CD30L)/CD30 receptor (CD30) system is expressed in certain malignancies, but has not been studied in thyroid nodules, we investigated its immunohistochemical expression in 6 normal thyroids (NT) and 131 thyroid nodules: 28 colloid nodules (CN), 45 adenomas (15 oncocytic [OA], 30 follicular [FA]) and 58 carcinomas (15 follicular [FTC], 1 insular [ITC], 6 anaplastic [ATC], 30 papillary [PTC], and 6 medullary [MTC]). NT and CN expressed neither CD30L nor CD30 (CD30L-/CD30-). Forty percent of OA and 20% of FA showed epithelial coexpression of CD30L and CD30, and interstitial expression of CD30L, which was also observed in the surrounding normal tissue. Within malignancies, epithelial coexpression of CD30L and CD30 was observed in 7% of FTC, 33% of ATC, 67% of PTC, and 67% of MTC. Only PTC and MTC showed epithelial expression of CD30L in the perinodular tissue with similar frequency (80% PTC, 75% MTC). PTC and MTC had the highest proportion of CD30L+ or CD30+ cells, and together with OA, a thus far unreported nuclear location of CD30L. In PTC, the proportion of CD30L+ cells and the prevalence of nuclear location of CD30L correlated inversely and directly, respectively, with aggressiveness. In conclusion, CD30L/CD30 signaling is activated only past the colloid nodule stage, most frequently in an autocrine fashion.

CD30 Ligand↗
PubMed2000

A chimeric mini-trypsin inhibitor derived from the oil rape proteinase inhibitor type III.

The design of chimeric proteins is a major field of interest in structural biology and biotechnology. The successful design of the chimeric protein composed by the minimized reactive site domain of the low-molecular-mass trypsin inhibitor from Brassica napus (var. oleifera) seed (Ser3-Lys35; mini-RTI-III) and murine dihydrofolate reductase (DHFR) is reported here. The DHFR-mini-RTI-III chimeric protein was expressed in Escherichia coli, purified by metal-chelate affinity chromatography and oxidatively refolded. The affinity of the purified and refolded DHFR-mini-RTI-III for bovine trypsin (K = 5.0 x 10(-10) M) was closely similar to that determined for native RTI-III (K = 2.9 x 10(-10) M), at pH 8.2 and 22.0 degrees C. DHFR-mini-RTI-III may be regarded as a tool in structure-function studies and for developing multifunctional and multidomain proteinase inhibitors.

Amino Acid Motifs↗
PubMed2000

Characterization of five new low-molecular-mass trypsin inhibitors from white mustard (Sinapis alba L.) seed.

Five new low-molecular-mass trypsin inhibitors belonging to the RTI/MTI-2 family were identified from white mustard (Sinapis alba L. ; MTI-2) seed. Purified MTI-2 consisted of a peptide mixture, displaying Ile or Arg at position 43, Trp or kynurenine (Kyn) at position 44, and C-terminal ragged ends. The occurrence of Ile or Arg at position 43 suggested that MTI-2 inhibitors originated from different genes. The presence of 5-oxo-proline (pyroglutamic acid; 5-oxoPro1) and Kyn44 reflected post-translational processing of the serine proteinase inhibitor. MTI-2 showed approximately 70% amino-acid identity with low-molecular-mass trypsin inhibitors isolated from oil rape (Brassica napus var. oleifera; RTI-III) seed and with serine proteinase inhibitors mapped in Arabidopsis thaliana chromosome II (ATTI). Furthermore, MTI-2 was homologous to brazzein, the sweet-tasting protein from Pentadiplandra brazzeana Baillon fruit ( approximately 30% amino-acid identity). Although snake-venom toxins showed a low amino-acid identity (< 20%) with MTI-2, RTI-III, and ATTI, some structurally relevant residues were conserved. The disulfide bridge pattern of MTI-2 (Cys5-Cys27, Cys18-Cys31, Cys42-Cys52, and Cys54-Cys57) corresponded to that of RTI-III and of snake-venom toxins, being different from that of brazzein. Therefore, protein similarity might be attributable to the three-dimensional arrangement rather than to the amino-acid sequence. Values of Ka for MTI-2 binding to bovine beta-trypsin (trypsin) and bovine alpha-chymotrypsin were 6.3 x 109 M-1 and 2.0 x 106 M-1, respectively, at pH 8.0 and 21.0 degrees C. Moreover, values of kon for MTI-2 binding to trypsin and of koff for the dissociation of the serine proteinase:inhibitor complex were 5.6 x 105 M-1.s-1 and 8.9 x 10-5 M-1.s-1, respectively, at pH 8.0 and 21.0 degrees C. Despite the heterogeneity of the purified inhibitor peptide mixture, the inhibition properties of the different MTI-2 inhibitors were indistinguishable.

Amino Acid Sequence↗
PubMed1999

Loss of heterozygosity of the long arm of chromosome 7 in follicular and anaplastic thyroid cancer, but not in papillary thyroid cancer.

Papillary thyroid cancer (PTC), but neither the follicular nor the anaplastic histotype [follicular thyroid cancer (FTC), anaplastic thyroid cancer (ATC)], overexpresses simultaneously the protooncogene HGF (hepatocyte growth factor) and its receptor HGF-R (or c-met). Because 1) HGF and c-met map to chromosome 7q21 and 7q31, respectively, 2) FTC loses genetic material at multiple loci with a frequency much higher than PTC, and 3) loss of heterozygosity (LOH) on 7q has been previously found in various tumors, we tested the hypothesis that both FTC and ATC, but not PTC, could harbor LOH in segments of 7q encompassing the loci for HGF and c-met. We screened 6 normal thyroids, 10 colloid nodules, 10 follicular hyperplasias, 10 oncocytic adenomas, 10 follicular adenomas (FA), 10 FTC, 6 ATC, 12 PTC using two microsatellite markers for HGF, and two for c-met. LOH for all 4 markers was found in 100% of FTC, 100% of ATC, and (for only 1 or 2 markers) in 10-29% of FA. This is the first demonstration of an LOH that separates both FTC and ATC from PTC, in the best possible manner: 100% vs. 0%. Clearly, each of the two segments we have probed contains at least one tumor suppressor gene, whose inactivation is crucial for the establishment of the FTC (and ATC) phenotype. This loss of genetic material explains why FTC and ATC, but not PTC, fail to express both HGF and c-met. Our findings may also have immediate diagnostic application, in the context of assisting pathologists in the often difficult task of distinguishing FA from FTC.

Adenocarcinoma, Follicular↗
PubMed1998

Expression of the hepatocyte growth factor and c-met in normal thyroid, non-neoplastic, and neoplastic nodules.

We have examined the coexpression of hepatocyte growth factor (HGF) and its receptor (HGF-R or c-met) in an archival series of 63 paraffin-embedded thyroid specimens plus one lymph node metastasis. By immunocytochemistry, we found undetectable expression of both the ligand and the receptor in 10 normal thyroids and 9 nonpapillary malignant nodules [5 follicular carcinomas, 1 poorly differentiated (insular) carcinoma, 3 undifferentiated (anaplastic) carcinomas]. Of 10 non-neoplastic nodules (colloid nodules) and 17 benign neoplastic nodules, 3 of 10 colloid nodules, 2 of 10 follicular adenomas, and 2 of 7 oncocytic adenomas showed a weak but distinct staining (1+ score in a scale from 0 to 4+) of both HGF and c-met in a modest proportion of cells (1% to 3%). In these 7 cases, expression of HGF was always stromal and expression of c-met limited to the membrane of the follicular cells. Of 3 malignant nodules derived from aberrant growth of the parafollicular C cells (medullary thyroid cancer or MTC), 2 were positive (6% of cells). In these 2 cases, the expression of HGF (3+) was not stromal, but in both the membrane and cytoplasm of the parafollicular cells, while that of c-met (3+) was restricted to the membrane. In contrast to all of the above, of 14 papillary carcinomas (PTC) encompassing 5 histological variants (conventional; follicular; oncocytic; with foci of solid growth; diffuse sclerosing) plus 1 neck lymph node metastasis of 1 conventional PTC, 12 (86%) expressed HGF, and 13 (93%) expressed c-met. With the exception of 2 negative cases, HGF was detected in 15% to 46% of the cells. The highest percentage (46%) pertained to conventional PTC cases with abundant peritumoral lymphocyte infiltration, indicating that some lymphokine(s) may recruit PTC cells for HGF expression in a paracrine fashion. With the exception of one negative case, c-met was found in 43% to 80% of the cells, both at levels from intense (3+) to very intense (4+). The immunostaining for HGF was stromal in 25%, membranous in 8%, cytoplasmic in 8%, and both membranous and cytoplasmic in 59% of the PTC-positive cases. The immunostaining for c-met was membranous in 43% and both membranous and cytoplasmic in 57% of the PTC-positive cases. In the lymph node metastasis and in the diffuse sclerosing variant of PTC (the most aggressive variant), the coexpression of HGF/c-met was lost, in that only c-met was expressed on membranes in both cases. We conclude that the HGF/c-met system is activated (by overexpression of both components) in the vast majority of PTC. In most PTC the interaction of HGF and its receptor (c-met) is autocrine, not paracrine.

Carcinoma↗
PubMed1997

[Principles of rehabilitation of patients with ileostomy].

Authors, believing that ileostomy is the cause of serious clinical, functional and psychological consequences, dwell upon principles of rehabilitation, which aim is the reinstatement of ileostomized patients into daily life. The most important aspect is to select the position of the stoma; it is necessary to consider some technical and functional aspects. The Authors examine local problems of the stoma, the unstable electrolytical balance, and report some therapeutical aspects. They expose early and late complications after surgical therapy and conclude underlining the advantages of a rapid social reinstatement of patients with an ileostomy.

Activities of Daily Living↗
PubMed1997

[Changes in serum levels of folic acid after total gastrectomy].

The Authors, in consideration that Folic Acid is assimilated in the upper alimentary tract, effected a comparative study between its seric levels in normal patients and in patients submitted to gastrectomy for gastric cancer, at different times from the operation. In the patients of the first group, Folic Acid levels were not correlated with sex, but to age, decreasing with the increasing of it. In gastrectomized patients, serum levels, also if acceptable, were always lower than in control cases, and gradually decreasing with the increasing of the age. The Authors conclude that, obviously, intestinal assimilation and endogenous reserves are able to counterbalance for enough long time the insufficient alimentary absorption.

Aged↗
PubMed1996

The plant oncogene rolD stimulates flowering in transgenic tobacco plants.

The Agrobacterium rhizogenes T-DNA oncogene rolD under the control of its own 5' regulatory region was transferred to day-neutral tobacco plants. The main trait induced by rolD in transgenic plants is a striking precocity in flower setting and a strong enhancement of the flowering potential. In rolD plants, early flowering is followed by the very rapid growth of numerous lateral inflorescences. The analysis of several morphological and histological parameters suggests that some characteristic morphological abnormalities observed in rolD plants can be accounted for by their early reproductive phase transition and points to the involvement in the transition of a greater portion of the plant body than is the case for untransformed tobacco. The in vitro morphogenic potential of tissues from rolD plants was also tested. Superficial thin cell layer explants from rolD plants show an earlier and much enhanced flower organogenesis, compared to controls, both on flowering and on hormone-free medium.

Cells, Cultured↗
PubMed1994

Bacterial plant oncogenes: the rol genes' saga.

The rol genes are part of the T-DNA which is transferred by Agrobacterium rhizogenes in plant cells, causing neoplastic growth and differentiation. Each of these bacterial oncogenes deeply influences plant development and is finely regulated once transferred into the plant host. Both from the study of the effects and biochemical function of the rol genes and from the analysis of their regulation, important insight in plant development can be derived. Some of the most intriguing aspects of past, current and future research on this gene system are highlighted and discussed.

Bacterial Proteins↗
PubMed1993

Correlative Association between Resident Plasmids and the Host Chromosome in a Diverse Agrobacterium Soil Population.

Soil samples collected from a fallow field which had not been cultivated for 5 years harbored a population of Agrobacterium spp. estimated at 3 x 10 CFU/g. Characterization of 72 strains selected from four different isolation media showed the presence of biovar 1 (56%) and bv. 2 (44%) strains. Pathogenicity assays on five different test plants revealed a high proportion (33%) of tumorigenic strains in the resident population. All tumorigenic strains belonged to bv. 1. Differentiation of the strains by restriction fragment length polymorphism analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of cellular proteins, and utilization patterns of 95 carbon substrates (Biolog GN microplate) revealed a diversified bv. 1 population, composed of five distinct chromosomal backgrounds (chr A, C, D, E, and F), and a homogeneous bv. 2 population (chr B). chr A, B, C, and D were detected at similar levels throughout the study site. According to opine metabolism, pathogenicity, and agrocin sensitivity, chr A strains carried a nopaline Ti plasmid (pTi), whereas chr C strains had an octopine pTi. In addition, four of six nontumorigenic bv. 1 strains (two chr D, one chr E, and one chr F) had distinct and unusual opine catabolism patterns. chr B (bv. 2) strains were nonpathogenic and catabolized nopaline. Although agrocin sensitivity is a pTi-borne trait, 14 chr B strains were sensitive to agrocin 84, apparently harboring a defective nopaline pTi similar to pAtK84b. The other two chr B strains were agrocin resistant. The present analysis of chromosomal and plasmid phenotypes suggests that in this Agrobacterium soil population, there is a preferential association between the resident plasmids and their bacterial host.

Journal Article↗