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G Magro

Publications and source records attributed to G Magro.

At least 37 records · Page 2Linked to original sources
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↗
PubMed2001

[The glial cell in the ontogenesis of the human peripheral sympathetic nervous system and in neuroblastoma].

The developmental role of glial cells in the human peripheral sympathetic nervous system is still unclear. Immunohistochemical studies on human embryos and fetuses reveal that the migrating clusters of undifferentiated neuroblasts contain sustentacular cells and are completely separated from adjacent tissues by a peripheral layer of Schwann-like cells and continuous basement membrane. This topographic distribution seems to be strategic and suggests a role of glial cells and extracellular matrix in migration and differentiation processes of undifferentiated neuroblasts. A similar distribution pattern between glial cells/extracellular matrix and neuroblasts can be observed in neuroblastomas exhibiting a microscopic nodular growth pattern, providing additional evidence that neuroblastoma represents an arrest in the differentiation/maturation of cells during the ontogenesis of the human peripheral sympathetic nervous system. Although it is commonly believed that Schwann cells in neuroblastoma arise from cells "infiltrating neoplasia", arising from peripheral nerves adjacent tumor, our ontogenetic findings suggest that the glial cell component of neuroblastoma derives from that normally associated with developing neuroblasts. We discuss the normal development of the three lineages of the human peripheral sympathetic nervous system (ganglial, neuroendocrine or chromaffin, and glial), with special emphasis on glial cells and extracellular matrix components and on the comparison between ontogenesis and neuroblastoma.

Basement Membrane↗
PubMed2000

Dichotomic effects of IFN-gamma on the development of systemic lupus erythematosus-like syndrome in MRL-lpr / lpr mice.

Systemic lupus erythematosus (SLE)-prone female MRL-lpr / lpr (MRL-lpr) mice were treated with mouse or rat IFN-gamma under different experimental conditions, both prophylactically in 6- to 8 week-old animals and therapeutically in 12- to 18-week-old SLE-affected mice. It was found that IFN-gamma heterogeneously modulated the course of the disease in MRL-lpr mice. When administered prophylactically, IFN-gamma favorably modulated the histological, serological and clinical signs of the disease. Relative to untreated or PBS-treated control animals, the MRL-lpr mice which received IFN gamma were virtually free of inflammatory infiltration of the kidneys and the lungs, had lower levels of azotemia with reduction of both circulating IgG1, IgG2a and IgG3 and anti-double strand (ds) and single strand (ss) DNA antibodies, milder skin vasculitis, significantly reduced enlargement of their lymph nodes and lower weight of the spleens. IFN-gamma also lowered the rate of mortality of MRL-lpr mice. In contrast to these findings, therapeutically administered IFN-gamma worsened the course of the disease in MRL-lpr mice, which exhibited increased proteinuria, higher levels of IgG2a and IgG3 and anti-ds and -ss DNA antibodies, more aggressive nephritis and died at an earlier age than PBS-treated control mice. The dichotomic effect of IFN-gamma on disease manifestation in MRL-lpr mice offers new insights into the complex role of this cytokine in the regulation of systemic autoimmunity such as SLE.

Animals↗
PubMed2000

Essential pathogenetic role for interferon (IFN-)gamma in concanavalin A-induced T cell-dependent hepatitis: exacerbation by exogenous IFN-gamma and prevention by IFN-gamma receptor-immunoglobulin fusion protein.

We have studied the effects of either exogenously-administered interferon (IFN-)gamma or of a nonimmunogenic mouse IFN-gamma receptor-Immunoglobulin (IFN-gamma R-Ig) fusion protein on the development of Concanavalin (Con)A-induced hepatitis in NMRI mice. PBS-treated control mice injected with 20 mg/kg ConA developed classical serological and histological signs of hepatitis with elevation of transaminases in the blood and infiltration of the liver by mononuclear cells and neutrophils. Treating the mice with rat IFN-gamma 24 h prior to and 1 h after ConA-challenge markedly exacerbated these signs of hepatitis in a dose-dependent fashion. Moreover, mice injected with lower, non hepatitogenic, doses of ConA (10, 5 mg/kg) became fully susceptible to develop hepatitis upon similar treatment with IFN-gamma. Concordantly, ConA-induced hepatitis was abrogated by either IFN-gamma R-Ig fusion protein or anti-IFN-gamma mAb. These data provide further evidence for the central pathogenetic role of endogenous IFN-gamma in ConA-induced hepatitis and demonstrate the feasibility to prevent disease development by means of a non immunogenic IFN-gamma R-Ig fusion protein.

Animals↗
PubMed2000

Cathepsin D is a marker of ganglion cell differentiation in the developing and neoplastic human peripheral sympathetic nervous tissues.

Cathepsin D (CD) is an aspartic proteinase which has been immunolocalised in intestinal ganglion cells of human neonates and adults. The aim of the present study was to define whether CD is a reliable ganglion cell differentiation marker in routinely fixed, paraffin-embedded tissues. For this purpose, we investigated immunohistochemically the expression and distribution of CD in the developing human peripheral sympathetic nervous system (PSNS) and gastroenteric nervous system (GENS), and in childhood neuroblastic tumours (NTs; neuroblastomas, ganglioneuroblastomas and ganglioneuromas), where ganglion cells differentiate from immature neuroblastic cells. During ontogenesis, CD expression is restricted to ganglion cell lineage with a progressively more intense cytoplasmic staining, mirroring the morphological differentiation of ganglion cells with increasing gestational ages. In neoplastic tissues, CD immunoreactivity was restricted to neuroblastic cells showing morphological features of gangliocytic differentiation (differentiating neuroblastomas, ganglioneuroblastomas) as well as to neoplastic ganglion cells (ganglioneuroblastomas, ganglioneuromas). We conclude that CD is a reliable ganglion cell differentiation marker, which can be used routinely to stain developing and mature ganglion cells in formalin-fixed, paraffin-embedded tissues. Furthermore, our results indicate that CD immunoreactivity in childhood NTs recapitulates the changes during normal PSNS development, as previously reported for Bcl-2 oncoprotein, c-ErbB2, insulin-like growth factor 2 and beta2-microglobulin. This is consistent with the current view that childhood NTs exhibit gene expression profiles mirroring those occurring during PSNS ontogenesis.

Adult↗
PubMed2000

Lipomatous myofibroblastoma: a potential diagnostic pitfall in the spectrum of the spindle cell lesions of the breast.

We report on two cases of myofibroblastoma (MFB) of the breast comprised predominantly of a mature fatty component, representing approximately three quarters of the entire tumour area. Both tumours consisted of a well-circumscribed lipomatous tumour mass containing dispersed nodular or irregularly shaped spindled cellular areas. The fatty component was represented exclusively by mature adipocytes, uniform in size and shape, lacking nuclear pleomorphism. The cellular areas contained spindly to oval cells with morphological and immunophenotypical features typical of MFB. The two components were so intimately admixed that a finger-like infiltrating growth pattern was apparent. The cases reported here as "lipomatous MFB" aim to clarify further the morphological spectrum of MFB of the breast. Lipomatous MFB may potentially mimic other benign or aggressive tumour-like lesions or even bland-looking malignant spindle cell tumours such as fibromatosis, nodular fasciitis, spindle cell lipoma, spindle cell liposarcoma, spindle cell variant of metaplastic carcinoma, spindle cell malignant myoepithelioma, and low-grade fibrosarcoma/malignant fibrous histiocytoma. The histogenesis of the present bimorphic mesenchymal tumours could be explained as the result of a dual, myofibroblastic and lipomatous, differentiation from a common pluripotential mesenchymal precursor cell, probably represented by the vimentin+/CD34+ fibroblast of the mammary stroma.

Aged↗
PubMed2000

Sustentacular cells in sporadic paraganglioma-like medullary thyroid carcinoma: report of a case with diagnostic and histogenetic considerations.

Sustentacular cells (SCs) are glial supporting cells of the fetal, adult normal, and neoplastic extra and adrenal human chromaffin cell lineage. SCs have also been identified in some cases of medullary thyroid carcinoma (MTC), raising both diagnostic and histogenetic problems. We report a rare case of a sporadic paraganglioma-like variant of MTC showing numerous S-100 protein and glial fibrillar acid protein (GFAP) positive SCs encircling neoplastic cells in a nesting (Zellballen) pattern similar to that observed in paragangliomas or pheochromocytomas. Although stromal amyloid deposits were only focally detected, diagnosis was immunohistochemically confirmed by immunoreactivity of the neoplastic cells for cytokeratin, CEA, calcitonin, chromogranin A, neuron-specific-enolase, and synapthopysin. As for the histogenesis of SCs, if we assume that MTC is a neural crest-derived tumor, it is likely that these cells reflect the ability of the common precursor cell to differentiate towards a sustentacular-type glial cell lineage in addition to the typical neuroendocrine one. This viewpoint is supported by the evidence that rare cases of MTC may contain neoplastic or supporting cells showing a multidirectional differentiation (usually neuroendocrine and melanocytic) that recapitulates the different cell lineages arising from the developing neural crests.

Carcinoma, Medullary↗
PubMed2000

Solitary neurofibroma of the mesentery: report of a case and review of the literature.

Neurofibromas of the gastrointestinal tract are usually associated with neurofibromatosis type 1 (Nfl), or they are exclusive manifestations of the so-called "familial intestinal neurofibromatosis". Gastrointestinal neurofibromas can rarely occur as sporadic lesions in the jejunum and stomach, and only exceptionally in the mesentery. A critical review of the literature revealed that only seven cases of solitary neurofibromas (SNFs) of the mesentery (six in the ileal mesentery; one in the gastrocolic mesentery) have been reported in patients without stigmata of Nf1. We report the clinicopathologic features of an additional case of SNF of the ileal mesentery, incidentally found in a patient with an advanced gastric carcinoma. Since there is increasing evidence that some patients may have some features of Nf1, including dermal or nodular SNFs alone - limited to one or more body segments - (segmental Nf1), the possibility that SNFs of the mesentery may also represent a segmental manifestation of Nf1 is postulated.

Adenocarcinoma↗
PubMed2000

Expression of steroid hormone receptors, their regulated proteins, and bcl-2 protein in myofibroblastoma of the breast.

AIMS: To investigate the possible role of steroid hormones in the pathogenesis of myofibroblastoma (MFB) of the breast, we analysed the immunohistochemical expression of oestrogen, progesterone, androgen receptors, their regulated proteins and bcl-2 protein in a series of this rare tumour. METHODS AND RESULTS: Paraffin-embedded sections from seven cases of MFB of the breast (five male; two female) were immunohistochemically tested for the expression of oestrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), oestrogen-regulated pS2 protein, androgen-regulated prostate-specific antigen (PSA) and bcl-2 protein. Rare cases of benign spindle cell tumours or tumour-like lesions of the breast (primitive fibromatosis, inflammatory pseudotumour, muscular hamartoma) which enter into the differential diagnosis with MFB, were also investigated and compared with MFB. All cases of MFB showed a diffuse (70-90% of neoplastic cells) and strong nuclear labelling with ER and PR, whereas AR was expressed only in three cases (two men and one woman) in about 60-70% of cells. Conversely, no immunostaining was detected for the pS2 protein and PSA. bcl-2 protein immunoreactivity was found in all cases of MFB, although with a variable degree of expression. No expression for steroid hormone receptors, their regulated-proteins and bcl-2 protein was observed in the rare benign spindle cell lesions of the breast included in this study. CONCLUSION: The in-situ detection of ER, PR and AR suggests that steroid hormones and their receptors are implicated in the pathogenesis of breast MFB. The consistent demonstration of bcl-2 protein, associated with a positive ER/PR status, provides evidence that bcl-2 may be an oestrogen-regulated protein also in MFB and that probably plays a role in the tumorigenesis. Finally, we postulate that the ER/PR and bcl-2 positive immunoprofile of MFB of the breast, in contrast to the negative profile of other rare primitive benign spindle cell lesions of the breast herein studied, might be exploited as an ancillary diagnostic aid in differential diagnosis of doubtful cases.

Actins↗
PubMed2000

Striated muscle cells in non-neoplastic lung tissue: a clinicopathologic study.

This study was performed to study the prevalence, origin, and clinical implication of striated muscle cells in congenital non-neoplastic lung abnormalities. Five cases of striated muscle cell proliferation within congenital non-neoplastic pulmonary abnormalities were identified from a series of 31 (16%) resected specimens obtained at King's College Hospital, London, during the period 1992 to 1998. Lung tissue was also obtained from 48 normal human fetuses and serial sections stained for the presence of striated muscle. A histologic and immunohistochemical study of the clinical cases and the fetal material was performed by using phosphotungstic acid hematoxylin staining and immunostaining for myoglobin and desmin. Striated muscle cells were identified either as a diffuse or a focal proliferation within the lung interstitia of five infants. The congenital lung anomalies were intra-abdominal pulmonary sequestration associated with congenital cystic adenomatoid malformation (CCAM), intrathoracic sequestration again with features of CCAM, an intrathoracic sequestration associated with a congenital diaphragmatic hernia, and 2 Stocker type II intrathoracic CCAMs. Striated muscle cells were not identified in any section of lung tissue derived from the fetal series. Striated muscle cells proliferation in non-neoplastic lung tissue is more common than usually reported. Although the exact origin of such cells is speculative, because it is always detected within pulmonary anomalies, a wide morphogenetic error is likely. The clinical implication of its presence has to be further defined. HUM PATHOL 31:1477-1481.

Adult↗
PubMed2000

Murine concanavalin A-induced hepatitis is prevented by interleukin 12 (IL-12) antibody and exacerbated by exogenous IL-12 through an interferon-gamma-dependent mechanism.

Concanavalin A (ConA)-induced hepatitis is a cell-mediated immunoinflammatory condition similar to human autoimmune hepatitis. We investigated the role of interleukin 12 (IL-12) in hepatitis induced in NMRI and C57/BL6 mice by a single injection of ConA. Recombinant murine IL-12 administered 24 hours and 1 hour prior to ConA exacerbated both transaminase activities in plasma and histologic signs of hepatitis. These markers of liver injury were significantly reduced by prophylactic, but not therapeutic treatment with anti-IL-12 monoclonal antibody (mAb). The disease-modulatory effects of IL-12 and anti-IL-12 mAb were associated with profound and reverse modifications of a ConA-induced increase in the circulating levels of IL-4, IL-6, interferon gamma (IFN-gamma) and tumor necrosis factor (TNF). Relative to control animals receiving ConA alone, the plasma levels of these cytokines were all augmented in IL-12/ConA-treated mice and diminished in anti-IL-12 mAb/ConA-treated mice. Anti-IFN-gamma mAb also impeded the appearance of IL-12/ConA-induced hepatitis. Thus, IL-12-induced production of IFN-gamma might play a role in mediating the hepatitis-inducing effect of ConA. However, IL-12p40-deficient C57/BL6 mice were as susceptible as wild-type controls to the hepatitis-inducing effect of ConA.

Animals↗
PubMed2000

Localized fibrosis of the corpus cavernosum: an example of fibrosis arising from the vascular smooth muscle cells. Report of a case with histogenetic considerations.

We report a rare case of a localized fibrosis of the corpus cavernosum (CC) presenting as a nodular mass in the dorsal region of the penis without abnormal curvature of the organ. Histological and immunohistochemical examination revealed a fibrotic process, involving CC but not tunica albuginea, arising from the smooth muscle cells of the vascular channels. Two different morphological phases were identified in these vascular lesions: proliferative and residual phase. The proliferative phase was characterized by hyperplasia and moderate fibrous thickness of the smooth muscle layer of the vascular channels of CC, resulting with the formation of concentric perivascular cuffs and nodules. The residual phase was characterized by a progressive nodular fibrotic transformation with narrowing of the original vascular channels and replacement of the normal CC structures. The cells of this phase exhibited an immunophenotype of both fibroblasts (vimentin+; alpha-smooth muscle actin-) and myofibroblasts (vimentin+; alpha-smooth muscle actin+). The clinicopathological features of the lesion and histogenetic considerations are discussed.

Fibrosis↗
PubMed2000

Responsiveness of irradiated rat anterior pituitary cells to hypothalamic releasing hormones is restored by treatment with growth hormone.

Hypopituitarism is a common sequela of irradiation in cancer patients. Here we report that recombinant human growth hormone (r-hGH) prevents cell death and restores secretory capacity of irradiated rat pituitary cells in vitro. Dispersed rat pituitary cells from male Sprague-Dawley rats, irradiated with a 9-Gy sublethal dose, were incubated with r-hGH before, after, or before and after irradiation. Treatment with GH resulted in increased cell survival, which reached its maximum at the concentration of 5 nM, with an EC(50) of 3.5 nM. Protective effects of GH on pituitary cells were more pronounced in cultures treated before and after irradiation. Similarly, beneficial effects of GH were observed on the secretory capacity of surviving cells. In fact, irradiated pituitary cells treated with GH secreted substantial amounts of GH, luteinizing hormone, follicle-stimulating hormone, prolactin, thyroid-stimulating hormone and adrenocorticotropic hormone in response to specific releasing hormones. Such effects of GH were prevented in the presence of the specific GH receptor antagonists B2036 and G120K. Our results show that r-hGH exerts a specific protective effect on irradiated rat pituitary cells and suggest possible use of GH as an adjuvant agent for prevention of postirradiation hypopituitarism.

Adrenocorticotropic Hormone↗
PubMed1999

Prevention by rolipram of concanavalin A-induced T-cell-dependent hepatitis in mice.

Rolipram is a type IV phosphodiesterase inhibitor endowed with powerful immunomodulatory properties. In this study, we evaluated the effects of this drug on the development of the T-cell-mediated hepatitis inducible in mice by concanavalin A. The results indicated that prophylactic treatment with either 5 or 10 mg/kg rolipram injected intraperitoneally 24 h and 1 h prior to intravenous (i.v.) challenge with 20 mg/kg concanavalin A successfully ameliorated serological and histological signs of liver damage, so that the treated mice showed lower transaminase levels in the plasma and milder mononuclear cell infiltration of the liver as compared to vehicle-treated controls. Moreover, this effect was associated with profound modifications of circulating levels of cytokines released after concanavalin A injection, with the blood levels of interferon-gamma and tumor necrosis factor-alpha being significantly lower and those of interleukin-10 higher than those of the control mice. In particular, the increased blood levels of interleukin-10 might play an important role in the anti-hepatitic effects of rolipram as coadministering this compound with anti-interleukin-10 monoclonal antibody significantly reduced its anti-inflammatory action. These results suggest that rolipram may be useful in the clinical setting for the treatment of cell-mediated immunoinflammatory diseases such as immunoinflammatory hepatitis.

Animals↗
PubMed1999

Myofibroblastoma of the breast with hemangiopericytoma-like pattern and pleomorphic lipoma-like areas. Report of a case with diagnostic and histogenetic considerations.

Myofibroblastoma (MFB) of the breast is an uncommon benign spindle cell tumor which may exhibit a wide spectrum of histological features. We report an unusual case of MFB of the male breast, showing cellular areas with a hemangiopericytoma-like pattern similar to that observed in solitary fibrous tumor (SFT) and extensive fibromyxoid areas containing numerous atypical stromal cells. The association of these atypical cells with mature adipocytes and microcystic and/or myxoid degenerative changes resembled pleomorphic lipoma-like and myxoid liposarcoma-like features, respectively. To our knowledge, these peculiar morphological findings have not been previously reported in MFB of the breast. They should be recognized to avoid confusion with other mesenchymal tumors, especially with hemangiopericytoma, pleomorphic lipoma (PL), spindle-cell lipoma (SCL) and myxoid liposarcoma. A case of MFB of the breast showing morphological features also commonly seen in SFT and PL/SCL is further morphological evidence in support of the speculation that the mesenchymal tumors of the breast, also known under the terms benign spindle cell tumors, fibromas, SFTs, SCLs and MFBs, are histogenetically related lesions.

Biomarkers, Tumor↗