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G Coggi

Publications and source records attributed to G Coggi.

At least 73 records · Page 4Linked to original sources
PubMed1989

Coexpression of cytokeratins and vimentin in normal and diseased thyroid glands. Lack of diagnostic utility of vimentin immunostaining.

We documented the coexpression of cytokeratins and vimentin in epithelial cells of the thyroid gland in 100 samples examined from 65 patients. These included normal, inflammatory, and neoplastic tissues that were routinely fixed in formalin and embedded in paraffin. The number of epithelial cells coexpressing the two intermediate filament proteins as well as the subcellular compartmentalization of vimentin immunoreactivity did not correlate with the various conditions of the thyroid gland. Therefore, we conclude that the immunolocalization of vimentin does not represent a useful adjunct tool for the histopathological diagnosis of thyroid diseases.

Humans↗
PubMed1988

Coexpression of cytokeratins and vimentin in common epithelial tumours of the ovary: an immunocytochemical study of eighty-three cases.

An immunocytochemical investigation has been performed on 83 common epithelial tumours of the ovary, to ascertain their capability of expressing vimentin in addition to cytokeratins. Our results demonstrate that vimentin coexpression is related to the tumour histotype and -to a lesser extent- to the degree of differentiation of malignant variants. Indeed, most serous tumours (80%), some endometrioid adenocarcinomas, and all the clear cell carcinomas investigated exhibited a variable number of neoplastic cells co-synthesizing the two distinct intermediate filament (IF) proteins, whereas only one of 29 mucinous tumours and none of the Brenner tumours displayed vimentin-immunoreactive cells. Moreover, in serous and endometrioid carcinomas, the expression of vimentin was related to the degree of tumour differentiation, being consistently identifiable in the better differentiated cases. The immunocytochemical findings of a parallel investigation on IF expression in the ovarian coelomic epithelium and in the müllerian-derived epithelia of the female genital tract allowed us to ascertain that ovarian epithelial tumours (with the possible exception of poorly differentiated carcinomas) maintain the pattern of IF expression typical of the normal epithelia. This investigation emphasizes the usefulness of IF typing as a tool for the more precise characterization of the origin and differentiation of human neoplasms.

Adenocarcinoma↗
PubMed1988

Infantile digital fibromatosis-like tumour (inclusion body fibromatosis) of adulthood: report of two cases with ultrastructural and immunocytochemical findings.

Two adult cases of a cutaneous lesion indistinguishable from typical infantile digital fibromatosis are added to the unique similar case so far reported in adulthood. The immunocytochemical localization of vimentin and muscle actin in the proliferating cells confirms their myofibroblastic nature and establishes closer relationships between the adult and the infantile variants of this entity. These two variants, however, appear to be clinically different, since all the adult cases were extradigital and did not recur after surgical excision. The term inclusion body fibromatosis underlines the histological hallmark of the lesion and should be used to identify this entity in place of recurrent infantile digital fibromatosis which does not seem any longer appropriate.

Actins↗
PubMed1988

Glial fibrillary acidic protein immunoreactivity in human respiratory tract cartilages and pulmonary chondromatous hamartomas.

Immunocytochemical investigation was performed on a large series of adult, neonatal, and fetal respiratory tract cartilages to ascertain their immunoreactivity for glial fibrillary acidic protein (GFAP) and vimentin. Two polyclonal and six different monoclonal antibodies were used to document the presence of GFAP-immunoreactive chondrocytes in all the fetal and neonatal cartilages as well as in the adult epiglottis, arythenoids, and lobar, segmental, and subsegmental bronchi. The number of chondrocytes showing GFAP immunoreactivity decreased from fetal life to adulthood. Simultaneous immunoreactivity for GFAP and vimentin has also been ascertained in chondrocytes and in perichondrial stellate or elongated cells of the 25 chondromatous hamartomas investigated. These findings document yet another "inappropriate" pattern of intermediate filament immunoreactivity in normal and neoplastic human cells, and contradict the widely held supposition that the expression of GFAP is restricted to cells of glial origin.

Adult↗
PubMed1988

Univariate and multivariate analysis of associated factors of retinopathy in 894 Italian adult diabetics.

The prevalence of diabetic retinopathy and the evaluation of its risk factors is poorly known in Italian population. Therefore, we have studied 894 diabetic outpatients (420 males, 474 females, 27.6% IDDs, 38.1% insulin-treated) in order to investigate the effect of clinical and metabolic characteristics on the frequency of diabetic retinopathy, classified into six different classes. In univariate analyses age, duration of disease, systolic and diastolic blood pressure, blood urea nitrogen, 24 hr proteinuria and fasting glycemia significantly correlated (p less than 0.001) with severity of retinopathy. The significance was confirmed in multivariate analysis for duration, age and systolic blood pressure (p less than 0.001). Stratification by type of diabetes showed that undefined onset of diabetes probably reduced in NID patients the power of duration as an associated factor of retinopathy. Worsening of this complication in three clinical classes of therapy (diet, oral and insulin-treatment) is evident too. Finally, our 11 variables in the step-wise multiple-regression analysis explain only 16.8% of diabetic retinopathy in all patients, but 36.6% in selected ID subjects.

Adolescent↗
PubMed1987

Ultrastructural immunolabeling in renal diseases. Past, present and future expectations.

The use of immunoelectron microscopy in the evaluation of renal diseases represents a valuable addition to existing techniques. The ability to immunolabel immune-complex deposits for light- and heavy-chain determinants, and complement fractions virtually eliminates the need for traditional immunofluorescence. One of the main advantages of performing immunoelectron microscopy relates to the fact that immunologic events can be adequately correlated morphologically with the degree and type of tissue reactions in the various renal compartments. Immunopathogenetic mechanisms can be clearly evaluated with this technique. The need to submit specimens in different fixatives is eliminated and all diagnostic modalities can be performed on a single fragment of tissue. The examination of the thick sections prepared from plastic-embedded tissue for survey provides excellent material for interpretation of findings at the light-microscopic level. These sections can be stained with hematoxylin/eosin, trichrome, silver methenamine and PAS stains with excellent results. The time and resources needed for processing renal biopsies can be significantly reduced by utilizing the proposed methodology. Likewise, interpretation of results may benefit from utilization of the same fragment for all diagnostic modalities.

Complement System Proteins↗
PubMed1987

Choroid plexus tumors. An immunocytochemical study with particular reference to the coexpression of intermediate filament proteins.

Sixteen choroid plexus tumors (CPTs) have been investigated for the localization of different immunocytochemical markers of epithelial and nonepithelial nature, namely, simple epithelial-type cytokeratins, vimentin, glial fibrillary acidic protein (GFAP), a panepithelial antigen defined by the lu-5 monoclonal antibody (lu-5 antigen), S-100 protein, and epithelial membrane antigen (EMA). Intermediate filament proteins have been identified in paraffin sections of 14 of 16 cases (87.5%). In all these tumors, cytokeratins and vimentin were constantly coexpressed by the neoplastic cells, in a manner similar to that of the cells lining normal choroid plexus. In 7 of these 14 cases, in addition to cytokeratins and vimentin, the neoplastic cells were shown to coexpress GFAP, which is not synthesized by their normal cell counterpart. The appearance of GFAP immunoreactivity in CPTs might be related to an ependymal differentiation of the neoplastic cells, because normal ependyma and ependymomas constantly coexpress GFAP and vimentin. The simultaneous expression of three distinct intermediate filament proteins by the same neoplastic cells is an exceedingly rare phenomenon, which has never been reported by double labeling technique in neoplasms of the central nervous system. Despite the complex antigenic profile of the CPT, which includes immunoreactivity for lu-5 antigen, S-100 protein, and EMA in most of the cases, positivity for three different epithelial markers indicates that these tumors have an epithelial nature. Moreover, the immunocytochemical typing of CPT with the panel of antibodies used in the current investigation allows differentiation from other primary and metastatic central nervous system tumors.

Antibodies, Monoclonal↗
PubMed1986

Ultrastructural localization of extracellular immunoglobulins in immune-complex-mediated glomerulonephritis. Immunoelectron microscopy of Epon-embedded human renal biopsies using the immunogold staining procedure.

The ultrastructural localization of immunoglobulins (Igs) in immunologically mediated glomerulonephritis was achieved in ultrathin sections of glutaraldehyde-fixed, post-osmicated, Epon-embedded human renal needle biopsies using the indirect immunogold staining procedure. Extracellular Igs were identified in electron-dense deposits in subendothelial, intramembranous, subepithelial and mesangial locations in different cases of immune-complex-mediated glomerulonephritis. The excellent preservation of the ultrastructural morphology of the tissue sections made it possible to precisely correlate the presence and distribution of the antigens with those of the electron-dense deposits, which are the ultrastructural hallmarks of these diseases. Our post-embedding staining procedure which allows extracellular Igs to the accurately localized should be a very useful tool for immunomorphological investigations of glomerulonephritis.

Glomerulonephritis↗
PubMed1986

T-cell subsets in sarcoidosis: an immunocytochemical investigation of blood, bronchoalveolar lavage fluid, and prescalenic lymph nodes from eight patients.

T-lymphocyte subsets in peripheral blood, bronchoalveolar lavage fluid, and prescalenic lymph nodes from eight patients with sarcoidosis were evaluated with monoclonal antibodies. Both in lung and lymph nodes significant increases in helper T cells were demonstrated, except in patients with stage III pulmonary disease or with unaffected lymph nodes. A good statistical correlation was observed between the activity of the disease (expressed by an increased ratio of helper to suppressor/cytotoxic T cells) in bronchoalveolar fluid and in lymph node cell suspensions from each patient. A three-step immunoperoxidase staining reaction, performed on lymph node frozen sections, showed a prevalence of helper T cells both inside and around the granulomas. These findings confirm that sarcoidosis is characterized by increased activity of cell-mediated immunity in its different localizations.

Adult↗
PubMed1985

Vasoactive intestinal polypeptide-, somatostatin-, and calcitonin-producing adrenal pheochromocytoma associated with the watery diarrhea (WDHH) syndrome. First case report with immunohistochemical findings.

A 30-year-old man presenting with watery diarrhea, hypokalemia, and hypochlorhydria (Verner-Morrison syndrome, WDHH syndrome) had raised plasma levels of vasoactive intestinal polypeptide (VIP), somatostatin (SRIF), calcitonin, and gastrin, as well as high urinary excretion of vanillylmandelic acid. A right adrenal pheochromocytoma was found and excised. The neoplastic cell population was immunohistochemically shown to contain VIP, SRIF, and calcitonin. Gross, histologic, and immunohistochemical evaluation of the pancreas revealed no abnormalities, whereas a marked hyperplasia of the gastrin-producing cells of the gastric antral mucosa was demonstrated. Postoperatively, the patient recovered from his symptoms and the plasma hormone levels returned to normal values. The clinical and histogenetic implications of this most unusual tumor of neural crest derivatives are discussed.

Adenoma, Islet Cell↗
PubMed1985

The iris vessels in the exfoliation syndrome: ultrastructural changes.

The ultrastructure of iris vessels in exfoliation syndrome has been investigated. Deposits of exfoliation material have been found in the vessel walls. There is evidence of different stages of pathological alterations of some vessels, culminating in the loss of endothelial cells and obliteration of the lumen associated with exfoliative deposits. These findings correlate with fluorescein angiographic alterations of the iris and stress the importance of vascular changes in this syndrome.

Aged↗
PubMed1985

Ultrastructural localization of intracellular immunoglobulins in Epon-embedded human lymph nodes. An immunoelectron microscopic investigation using the immunogold staining (IGS) and the avidin-biotin-peroxidase complex (ABC) methods.

The ultrastructural localization of intracellular immunoglobulins on ultrathin sections of glutaraldehyde-fixed, postosmicated, and Epon-embedded human lymph nodes has been achieved using such highly sensitive immunocytochemical techniques as immunogold staining and avidin-biotin-peroxidase complex. These immunoelectron microscopic techniques allow the identification of intracellular immunoglobulins without affecting the ultrastructural morphology of the tissue, since they do not require any pretreatment of the sections with proteolytic enzymes or deresinating agents. Therefore, immunoglobulins can be precisely localized in the cell organelles; structures whose morphology is well preserved. The availability of a reliable postembedding staining procedure for the ultrastructural localization of immunoglobulins is of definite value for investigations on human lymphoid tissue, both normal and pathological.

Avidin↗
PubMed1984

Immunoelectron microscopy of human renal biopsies: prerequisites and limitations.

The traditional diagnostic approach to immunologically mediated glomerulonephritis is based on the morphological (both in light and electron microscopy) and immunofluorescence examinations of different samples of the same renal biopsy. A major disadvantage of this composite procedure is represented by the inability to precisely correlate the immunocytochemical data with the presence and distribution of electron-dense deposits. Immunoelectron-microscopic techniques could therefore represent a more useful tool for immunomorphological investigations into these glomerulopathies. In order to overcome the significant limitations of preembedding staining procedures, we introduce two postembedding staining techniques (using peroxidase or colloidal gold as markers of the immunoreaction) which result in a precise immunolocalization of immunoglobulins in the dense deposits of glutaraldehyde-fixed, postosmicated and Epon-embedded renal biopsies, while adequately preserving the ultrastructural morphology of the tissue sections.

Biopsy↗
PubMed1983

Morphologic evaluation of the liver in hereditary angioedema patients on long-term treatment with androgen derivatives.

17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses.

Adult↗
PubMed1982

Immunohistochemical localization of human immunoglobulins and lysozyme in epoxy-embedded lymph nodes: effect of different fixatives and of proteolytic digestion.

The postembedding immunoperoxidase staining technique for the localization of immunoglobulins (light and heavy chains) and of lysozyme has been successfully applied to epoxy-embedded human lymph nodes, after removal of the resin. Glutaraldehyde-containing fixatives appear to be suitable for the immunohistochemical localization of human immunoglobulins and lysozyme, provided that the masked antigenicity of these proteins is recovered by proteolytic digestion of the tissue sections using 0.4% pepsin or 0.1% trypsin. Nonglutaraldehyde-containing fixatives allow the immunolocalization of human immunoglobulins without any enzymatic pretreatment. This study shows that tissues routinely fixed in glutaraldehyde and embedded for ultrastructural investigations are actually suitable for immunohistochemical studies on human immunoglobulins and lysozyme.

Female↗