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Biomedical subjects

M Cintorino

Publications and source records attributed to M Cintorino.

At least 37 records · Page 2Linked to original sources
PubMed1999

An interlaboratory study to determine the presence of human papillomavirus DNA in esophageal carcinoma from China.

Esophageal-carcinoma samples originating from the high-incidence area of China were tested in 2 different laboratories, each using a different degenerate PCR approach. Results confirmed the notion that none of the PCR approaches available for HPV-DNA detection today, is optimal for detecting all known HPV types at equal sensitivity and specificity. In combining results obtained in both laboratories, HPV DNA was demonstrated in 20/117 (17.1%) esophageal-carcinoma samples analyzed. HPV DNA was detected in 3/70 (4.3%) diagnostic biopsies, 7/23 (30.4%) surgical specimen and 10/24 (41.6%) cytological scrapings originating from the entire surface of the esophagus. Mucosotropic HPV types were present in 7/117 (6%) samples, only 3 being of the high-risk types (HPV 16, 18, 33). Other mucosal types found were HPV 6, 11, 13, 53 and 54. Cutaneous HPV types were present in 14/117 (12.0%) samples. HPVs 20 and 38 were present in 3 (2.6%) of the total samples and, in each case, together with another HPV type within one lesion. Two putative new HPV types, DL347 and DL 369, were identified.

Adult↗
PubMed1999

Expression of 11 beta-hydroxysteroid dehydrogenase in early pregnancy: implications in human trophoblast-endometrial interactions.

Glucocorticoid hormone action in target tissues is modulated by 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD), which interconverts active cortisol and corticosterone and their inert 11-keto metabolites, cortisone and 11-dehydrocorticosterone. Two different 11 beta-HSD isoforms exist: a low-affinity NADP-dependent dehydrogenase/oxoreductase (11 beta-HSD1) and a high-affinity NAD-dependent dehydrogenase (11 beta-HSD2). This brief review describes the expression and distribution of 11 beta-HSD isoforms in human placenta. In particular, it discusses the results of studies dealing with the expression of 11 beta-HSD activity in experimental models representative of the fetomaternal interface in the early gestation. The findings have implications in terms of protection of the fetus against corticosteroid toxicity and modulation of active glucocorticoid levels and their biological effects in early pregnancy.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1999

Expression of macrophage migration inhibitory factor transcript and protein by first-trimester human trophoblasts.

Macrophage migration inhibitory factor (MIF) was originally identified for its capacity to inhibit the random migration of macrophages in vitro. To date, the role of MIF as a pro-inflammatory cytokine, pituitary hormone, and counter-regulator of glucocorticoid action on the immune response is commonly recognized. Although recent studies suggest an involvement of MIF in reproduction, no data exist on the expression of this cytokine in early human pregnancy. In this study, we evaluated the presence of MIF protein and mRNA in specimens of chorionic villi from first-trimester human placenta. Tissues were obtained at 6-10 wk of gestation and analyzed by Western blotting, reverse transcription-polymerase chain reaction, and immunohistochemistry. Our results demonstrate that human villous tissue is a novel site of MIF synthesis. In addition, immunohistochemical analysis identified MIF protein in the cytotrophoblasts of both the inner layer of villi and in the trophoblastic cell islands. We speculate that in view of its proinflammatory features, MIF might play a critical role in human implantation and in early embryonic development.

Blotting, Western↗
PubMed1998

11Beta-hydroxysteroid dehydrogenase expression in first trimester human trophoblasts.

This study evaluated the levels and the enzymatic characteristics of 11beta-hydroxysteroid dehydrogenase activity (11beta-HSD) of chorionic villi isolated from first trimester human placenta. The results demonstrated a predominant expression of the NAD-dependent dehydrogenase isoform (11beta-HSD2) over the NADP-dependent oxoreductase (11beta-HSD1). Thus, in tissue homogenates exogenous NAD increased the conversion of corticosterone to 11-dehydrocorticosterone of about 14-fold while NADP was ineffective. There was no conversion of 11-dehydrocorticosterone to corticosterone either with NADH or NADPH demonstrating the lack of reductase activity. In keeping with these results, RT-PCR analysis indicated a mRNA for 11beta-HSD2 in villous tissue while 11beta-HSD1 mRNA levels were undetectable. In addition, immunohistochemical staining localized the 11beta-HSD2 protein to syncytiotrophoblasts and cell columns of the chorionic villi. These results suggest roles for the trophoblast-associated 11beta-HSD2 oxidative activity in modulating the exposure of the embryo to active glucocorticoids in the early gestation and in regulating trophoblasts invasion of the uterine wall.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1998

Charge heterogeneity of macrophage migration inhibitory factor (MIF) in human liver and breast tissue.

Macrophage migration inhibitory factor (MIF) is an ubiquitous protein playing various immunological and hormonal roles. Theoretical electrophoretic coordinates calculated from protein sequence in the SWISS-PROT database (AC P14174) are 12 kDa and pI 8.24. Using two-dimensional (2-D) immunoblotting, we have detected isoelectric forms at ca. 11.9 kDa, with pI values of 7.8 and 6.98 in human liver tissue, breast tissue and a cell line and in preparations of human MIF expressed in E. coli. This evidence suggests that MIF charge heterogeneity originates from a post-translational modification not requiring eukaryote-specific enzymes. We have also detected in human liver a minor immunoreactive spot at pI 6.23, which coincides with the MIF spot in the liver map in SWISS-2DPAGE. The pI 6.23 isoform also conceivably derives from post-translational modification, as MIF is known to be encoded in the human genome by a single copy gene.

Amino Acid Sequence↗
PubMed1998

Neuronal intranuclear inclusion disease: neuropathologic study of a case.

We report neuropathological findings in a 22-year-old man affected with neuronal intranuclear inclusion disease. The inclusions affected to different extents the various structures of the central nervous system, being more numerous in cerebral cortex, inferior olives, hypoglossal and oculomotor nuclei. They ultrastructurally differed from Marinesco bodies. In the neurons of the substantia nigra, we occasionally observed intranuclear inclusions resembling the so-called rodlets of Roncoroni. We did not observe inclusions in the extraneuronal tissues. There was no apparent correlation between frequency of the inclusions and neuronal loss. Intranuclear inclusions were found in many morphologically normal neurons. We suggest that the intranuclear inclusions are the marker of a distinctive disorder, even though their role in neuronal degeneration remains to be clarified.

Adult↗
PubMed1998

Hürthle cell tumor dwelling in hot thyroid nodules: preoperative detection with technetium-99m-MIBI dual-phase scintigraphy.

UNLABELLED: Single injection dual-phase scintigraphy (early and late acquisitions) with 99mTc-MIBI was used to differentiate benign and malignant hot thyroid nodules. METHODS: Thirteen euthyroid and two hyperthyroid patients displaying a hot thyroid nodule on the 99mTc scan due to an autonomously functioning thyroid nodule (AFTN) underwent early (15-30 min) and late (3-4 hr) thyroid scintigraphy after the administration of 740-1000 MBq 99mTc-MIBI. Visual scoring was done to assess nodular tracer uptake and retention. In addition, the nodular-to-thyroid (N/T) uptake ratio in the early and late image and the washout rates (WO) from the nodule and thyroidal tissue were measured. All patients underwent thyroid surgery. RESULTS: Histopathology revealed a Hürthle cell tumor in three nodules, a benign adenoma with oxyphilic metaplasia in two nodules and a benign adenoma without oxyphilic cells in the remaining 10 nodules. The Hürthle cell tumor nodules displayed intense and persistent uptake of 99mTc-MIBI (N/T was 2.81 +/- 0.52 and 5.53 +/- 1.06 in early and late images, respectively; WO from the nodule was 12.33 +/- 0.47, WO from the thyroidal tissue was 22.00 +/- 3.56). The benign nodules showed intense uptake in the early image and intense uptake to absent retention in the late image (N/T was 2.94 +/- 1.31 and 1.62 +/- 0.50 in the early and late images, respectively; WO from the nodule was 20.25 +/- 2.92, WO from the thyroidal tissue was 20.33 +/- 2.92). CONCLUSION: Single injection dual-phase 99mTc-MIBI scintigraphy of the thyroid with AFTN can identify nodules as a result of the activity of a Hürthle cell tumor, since these tumors cause intense and persistent tracer uptake in contrast with a benign AFTN.

Adenoma, Oxyphilic↗
PubMed1997

Protein expression profiles in human breast ductal carcinoma and histologically normal tissue.

Reference two-dimensional (2-D) gels are presented for human breast ductal carcinoma and histologically normal tissue. Whole biopsy fragments were analyzed, including epithelial and nonepithelial components. Thirty-five spots have been assigned by gel matching to the human liver SWISS-2DPAGE reference map and/or to the human primary keratinocyte IPG map from the Danish Center for Human Genome. N-terminal microsequencing was applied to confirm randomly chosen matching assignments and to identify six new spots. Protein expression profiles in ductal carcinoma and in normal breast tissue appeared to be similar, except for a pattern consisting of 32 spots, which were highly expressed in all carcinoma specimens, and less intense and occasionally undetectable in normal tissue. This difference was statistically significant. Assignment has been obtained for several spots, namely GRP94, GRP78, GRP75, mitochondrial HSP60, calreticulin, protein disulfide isomerase, peptidyl-prolyl cis-trans isomerase, collagen-binding protein 2, fructose bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, thioredoxin, cytochrome c oxidase VA subunit, tubulin beta isoform and macrophage migration inhibitory factor (MIF). The cancer- and tissue-specificity of the described pattern was assessed by matching to the Swiss-2DPAGE human liver, hepatoma, lymphoma, erythroleukemia reference maps. The pattern of 32 spots was found to be indicative of epithelial neoplasia.

Aged↗
PubMed1997

Distribution of type-I interferon-receptors in human first trimester and term placental tissues and on isolated trophoblast cells.

PROBLEM: Type-I interferon (IFN) is the protein recognizing pregnancy in ruminants. Although IFN is secreted in early pregnancy, its role is not still clear in other species. Like other cytokines, IFN exerts its biological functions through specific membrane receptors. We have investigated the potential action of IFN in human pregnancy by studying the distribution of the receptors in the human placenta. METHOD: Reactivity to monoclonal antibodies (mAbs) to the type-I IFN-receptor (R) was analyzed by immunohistochemistry in human placental tissues and in cytospins of first trimester trophoblast cells. RESULTS: Type-I IFN-R immunoreactivity was observed mostly in first trimester villous cytotrophoblasts and in the cytotrophoblast cell columns. Trophoblast in the decidua, the epithelium of the uterine glands, and most of the isolated trophoblast cells were also immunoreactive. CONCLUSION: The expression of type-I IFN-R in the highly proliferating and migrating trophoblast suggests that this cytokine has a role in trophoblast growth and invasion.

Antibodies, Monoclonal↗
PubMed1997

Human endometrial decidual cell-associated 11 beta-hydroxysteroid dehydrogenase expression: its potential role in implantation.

During pregnancy excess corticosteroid exposure can disturb the normal pattern of growth and differentiation of the primate fetus. This is normally prevented by the action of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD), which converts cortisol to its biologically inactive 11-oxo form, thereby ensuring that little or no cortisol is transferred to the fetus. During implantation, extravillous trophoblasts breech uterine vessels that are embedded in a decidual cell matrix. Through this invasive process the embryo gains requisite access to the maternal blood supply, while risking exposure to high circulating glucocorticoid levels. Thus, the expression of 11 beta-HSD by the decidual cell layer may be essential in regulating cortisol exposure of the developing embryo prior to placentation. In order to investigate the potential contribution of decidual cells to glucocorticoid metabolism, we evaluated the expression of both known 11 beta-HSD isoforms, 11 beta-HSD1, whose catalytic activity is NADP(+)-dependent, and NAD(+)-dependent 11 beta-HSD2, during decidualization of monolayers of human endometrial stromal cells. The differential actions of ovarian steroids on human endometrium are simulated in this in vitro model. Thus, progestins induce the expression of several decidualization markers in the cultured stromal cells, and consistent with its priming action in vivo, estradiol augments this expression. The results of our studies established a link between in vitro decidualization and enhanced glucocorticoid metabolizing capacity. Accordingly, the catalytic activities of both 11 beta-HSD isoforms were enhanced by incubation of the precursor stromal cells with medroxyprogesterone acetate, and further enhanced by estradiol, despite a lack of response to estradiol alone. This differential response to estradiol and progestin was reflected in parallel changes in steady state levels of 11 beta-HSD1 messenger RNA. The role of glucocorticoid metabolizing activity of the decidual cell is discussed in terms of its implications in determining the exposure of the implanting embryo to biologically active glucocorticoids.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1995

Localization of the Bcl-2 protein to the outer mitochondrial membrane by electron microscopy.

Incubation with the Bcl-2 antibody before fixation of tissues allowed good localization of the antigenic determinant. We showed that the Bcl-2 gene product in centroblastic-centrocytic lymphoma is mainly localized on the outer mitochondrial membrane and, to a lesser degree, on the nuclear envelope. No significant staining was found in other cytoplasmic domains. Careful examination also revealed that gold particles did not recognize an integral membrane epitope, but an antigenic determinant localized at a short distance from the cytoplasmic side of the membrane itself. This observation suggests that, by interacting with other cytoplasmic proteins, Bcl-2 plays some role in the cytoplasmic machinery involved in the regulation of programmed cell death.

Antibodies, Monoclonal↗
PubMed1995

Cytokines in the viviparous reproduction of squamate reptiles: interleukin-1 alpha (IL-1 alpha) and IL-1 beta in placental structures of a skink.

Placental viviparity is known in many species of squamate reptiles. Among these, some scincids have developed an epithelio-chorial chorio-allantoic placenta which in the structure of its central ridged zone is similar to those of certain therian mammalian species. A broad range of immunoregulatory peptides, cytokines, has been identified at the maternofetal interface of several species of mammals, either with invasive or non-invasive types of placenta. Thus we began to study whether interleukin-1, which is considered to play a crucial role in mammalian pregnancy, might also be involved in the viviparity of reptilian species. Placentae of Chalcides chalcides L. were processed by immunohistochemistry and incubated in a culture medium for different times. A very strong immunoreactivity for interleukin-1 alpha (IL-1 alpha) and for interleukin-1 beta (IL-1 beta) was present in the chorial epiblast and in uterine epithelial cells, with varying degree and localization in different periods of pregnancy. IL-1 beta was also released into the medium at different amounts during incubation. In light of the mammalian data, our results suggest that the role of cytokines in pregnancy may represent a significant event in the evolution of placental viviparity.

Animals↗
PubMed1995

Identification of Hürthle cell tumor by single-injection, double-phase scintigraphy with technetium-99m-sestamibi.

UNLABELLED: Early and late (double-phase) scintigraphy with 99mTc-MIBI was used in a comparative study of the scintigraphic aspects of Hürthle cell tumors and other thyroid tumors. METHODS: Single-injection, dual-phase (15-30 min and 3-4 hr) thyroid scintigraphy with 99mTc-sestamibi (MIBI) was performed on 41 patients who displayed a cold nodule on previous 99mTc scintigraphy. Visual scoring of nodular uptake was done to compare thyroidal and background tracer uptake. In addition, the nodular-to-thyroid (N/T) uptake ratio in the early and late images and the washout rate from the nodule (WON) and thyroidal tissue (WOT) were measured. Cytologic results were obtained for all patients; histopathologic results were obtained for the 20 patients who had surgery. RESULTS: In eight patients (Group A), the nodule displayed intense and persistent uptake of MIBI (N/T = 1.77 +/- 0.46 and 3.20 +/- 1.37; WON = 17.2% +/- 6.3%; WOT = 24.6% +/- 7.5%); histopathology revealed Hürthle cell tumors (two carcinomas and three adenomas) in five surgical patients. In 15 patients (Group B), the nodule displayed intense uptake in the early image with fading activity in the late image (N/T = 1.45 +/- 0.54 and 0.84 +/- 0.30; WON = 30.0% +/- 7.3%; WOT = 24.5% +/- 6.8%); histopathology revealed a colloid nodule (n = 1), papillary carcinoma (n = 4) and follicular carcinoma (n = 5) in 10 surgical patients. In the remaining 18 patients (Group C), the nodule was cold and late images were not acquired. Histopathology revealed colloid nodules (n = 2) and follicular adenoma (n = 3) in five surgical patients. CONCLUSION: Single-injection, dual-phase MIBI scintigraphy of the thyroid can identify Hürthle cell tumors because these tumors have intense, persistent tracer uptake in contrast to other thyroid tumors.

Adenoma, Oxyphilic↗
PubMed1994

First trimester human trophoblast expresses both interferon-gamma and interferon-gamma-receptor.

Interferon-gamma (IFN-gamma) is a lymphokine, produced by activated T lymphocytes, which plays a key regulatory role in the host immunological responses. In addition, IFN-gamma is expressed by human and porcine trophoblast. As IFN-gamma exerts its biological functions through specific cell surface receptors and a great number of IFN-gamma receptors (IFN-gamma R) have been purified from human placenta, we have examined the relative distribution of IFN-gamma and IFN-gamma R in human placental tissues at different stages of pregnancy. By using immunohistochemical analysis and monoclonal antibodies, it was found that IFN-gamma expression is intense in the first trimester but almost imperceptible at term, whereas the expression of IFN-gamma R is present at both stages of pregnancy. For both lymphokine and receptor, the most intense expression was observed in villous syncytiotrophoblast and in extravillous interstitial trophoblast. From these results it appears that the expression of IFN-gamma R in trophoblast is related to the presence of the lymphokine in the early phase of gestation but not later. On this basis, it can be argued that IFN-gamma exerts its functional role via an autocrine and/or a paracrine loop mainly during the first trimester.

Embryonic and Fetal Development↗
PubMed1994

The proliferating cell marker monoclonal antibody Ki-67 recognizes specific antigens associated with the nuclear envelope of the early Drosophila embryo.

Immunofluorescence and immunoelectron microscopy indicated that the antibody raised against the nuclear antigen Ki-67 of mammalian cells recognized antigenic determinants of early Drosophila embryos, localized on the outside of the nuclear envelope. Hence, the nuclear envelope of Drosophila appears to share a similar epitope with the chromosome scaffold of mitotic mammalian cells. With the progression of mitosis the antigen persisted around the mitotic spindle region and was also found in the pole regions at metaphase and anaphase. The antibody also stained the equatorial regions of the spindles from anaphase to late telophase. The antibody may therefore be used as a biochemical marker of the nuclear envelope for studying nuclear membrane biogenesis and behavior during the mitotic divisions of the Drosophila embryo.

Anaphase↗
PubMed1994

All histological types of primary human rhabdomyosarcoma express alpha-cardiac and not alpha-skeletal actin messenger RNA.

Eleven human primary rhabdomyosarcomas (RMSs), including all histological variants, were analyzed morphologically, immunohistochemically for intermediate filament proteins and actin isoforms, and by means of Northern blots with probes specific for total actin, alpha-skeletal (SK), alpha-cardiac (CARD), and alpha-smooth muscle actin messenger (m)RNAs. All tumors disclosed ultrastructural evidence of skeletal muscle features with terminal differentiation in three cases. The RMSs contained immunohistochemically the intermediate filament proteins vimentin and desmin and reacted positively with the alpha-sarcomeric actin antibody, which recognizes alpha-SK and alpha-CARD actin isoforms. All RMSs reacted with the total actin probe, recognizing at 2.1 kb cytoplasmic actin mRNAs and at 1.7 kb alpha-actin mRNAs. With the specific probes, all RMSs expressed alpha-CARD actin mRNA, four neoplasms expressed also alpha-smooth muscle actin mRNA, whereas the probe for alpha-SK actin mRNA never produced a signal except in one case, in which the tumor masses were intermingled with non-neoplastic preexistent striated muscle fibers. Because alpha-CARD and alpha-smooth muscle actins are transiently expressed during normal skeletal muscle development, RMSs seem to follow normal skeletal myogenesis without completing the final step, consisting of alpha-SK actin mRNA expression. The use of Northern blots for alpha-CARD actin as an adjunct to conventional techniques may be helpful for the precise identification of primary RMSs compared to other soft tissue neoplasms.

Actins↗