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G Valente

Publications and source records attributed to G Valente.

At least 91 records · Page 5Linked to original sources
PubMed1990

Endoscopic ultrasonography in eosinophilic infiltration of gastric wall.

The case of a young man with eosinophilic gastroenteritis with primary muscularis propria involvement in the antrum and distal ileum is presented. Initial diagnosis was based uniquely on indirect clinical and radiological findings since endoscopic and histologic data had been misled by the depth of eosinophilic infiltration. In order to directly prove the diagnosis, full-thickness operative biopsy would have been necessary but was avoided on ethical grounds. Valuable information was gained through Endoscopic Ultrasonographic (EUS) study of the antrum which showed an asymmetrical thickening of the outer hypoechoic layer of the wall corresponding to the muscularis propria. The overall thickness of the antrum amounted to 0.6 cm, clearly distinct from the 0.2 cm value in uninvolved areas. Subserosal involvement was also appreciated in spite of the absence of ascites; superficial layers, mucosa and submucosa, appeared uninvolved. The patient was restudied 6 months later when symptom-free: at this time, blood eosinophilia persisted and the EUS picture was unchanged. These observations suggest that peripheral blood eosinophilia along with eosinophilic infiltration of the gastric wall are stable conditions, unrelated to symptoms. Endoscopic ultrasonography is of value in ascertaining muscular involvement in eosinophilic gastroenteritis.

Adult↗
PubMed1990

[Tumors of the testicle].

The authors describe, in the light of the current literature, the clinical, diagnostic, and therapeutic characteristic of testicular cancer. They remark the good results of adjuvant therapy in this type of tumor.

Biomarkers, Tumor↗
PubMed1990

Infiltrating leukocyte populations and T-lymphocyte subsets in head and neck squamous cell carcinomas from patients receiving perilymphatic injections of recombinant interleukin 2. A pathologic and immunophenotypic study.

Nine patients with squamous cell carcinoma of the oral cavity and oropharynx underwent preoperative perilymphatic administration of recombinant interleukin 2 (rIL-2). A more marked eosinophil and lymphocyte infiltration and more extensive edema than in 13 untreated cases were observed in surgical specimens. Necrosis was present in five of nine cases, but involved no more than 10% of the neoplastic tissue; in three of nine cases, characteristic necrotic changes with intense eosinophil infiltration possibly induced by lymphokines involved the peritumoral soft tissues. Of the tumor-infiltrating lymphocytes, T-lymphocytes (mostly CD4+ cells) prevailed over B-lymphocytes. CD4+ and CD8+ cells were mainly located close to the neoplastic sheets. Moderate amounts of CD38+ and CD11c+ cells (macrophages) and few CD16+ and CD56+ lymphocytes were found in all cases. CD25+ and LAK1+ cells were significantly more numerous in treated than in untreated cases. This suggests that local administration of rIL-2 induces an increase in activated T-lymphocyte subsets infiltrating the neoplastic tissue, thus eliciting a tumor-specific T-lymphocyte reactivity.

Adult↗
PubMed1990

Heterogeneous subgroups among malignant diffuse small B cell lymphomas. A combined nucleometric and immunocytologic study.

The degree of heterogeneity among subtypes was evaluated in 39 of the most frequent malignant, diffusely growing small B cell lymphomas by a combination of morphometry, automated image analysis, and immunocytologic techniques. Cluster analysis of nuclear profile parameters, including nuclear area, circularity factor, and chromatin distribution pattern, distinguished 3 groups. Each group was characterized by the preponderance of certain nuclear profile types, i.e. (a) small, rather regular (roundish) and dark staining (typical small lymphocytic lymphomas and immunocytomas); (b) small to intermediate size, rather regular (roundish) and pale staining (small to intermediate size variant); or (c) small to intermediate size, irregular, rather pale staining (diffuse follicular small cleaved cell (centrocytic) lymphomas and, probably, polymorphous immunocytomas). Group 3 was clearly distinct from the rest, but groups 1 and 2 also differed significantly. Every case displayed a mixture of the 13 registered nuclear profile types. Lymphoid cells with similar nuclear profile features occurred in B cell zones of non-neoplastic lymph nodes. Frequency distribution of nuclear profile parameters significantly differed from one lymphoma group to another. However, there were considerable overlaps. No clear correlation was found between nuclear profile types and immunophenotypes. Cellular surface antigen patterns showed an extensive intra- and inter-case variability. The findings support the notion of a certain individuality of malignant B cell lymphomas and of a marked heterogeneity among their subtypes.

Adult↗
PubMed1990

[Gingival fibromatosis. A clinical, therapeutic and histopathological study of a new case].

The aetiopathogenesis, histology and clinical treatment of a rare case of familial gingival fibromatosis are analysed with particular emphasis on the relationship between the histological picture and the pathogenesis of the condition. In tackling the problem of treatment, the paper recommends the use of gingivectomy with an internal rather than the classic external chamfer.

Adult↗
PubMed1989

Regulation of cell turnover in the livers of tumour-bearing rats: occurrence of apoptosis.

Growth of a highly-deviated ascites hepatoma (Yoshida AH-130) in rats caused initial hyperplastic enlargement of the liver, followed by progressive reduction to a size lower than that seen in controls. The time-course of this biphasic change in liver weight roughly corresponded to the exponential and stationary phases of tumour growth. Histologically, scattered small foci of perilobular necrosis were observed during the hyperplastic phase and these were consistently associated with a moderate elevation of glutamate-pyruvate transaminase (GPT) activity in the blood plasma. By contrast, signs of necrosis were absent and plasma GTP levels had returned to normal during the phase of hepatic involution, which was characterized by enhanced apoptosis, a type of single-cell death known to be involved in the regulation of tissue size under both normal and pathological conditions. Biochemically, alterations in liver protein mass resulted from changed rates of tissue protein degradation. The apoptotic bodies could either be lost from the liver via blood, lymph and bile, or phagocytosed and degraded by adjacent cells. Disposal of the apoptotic bodies is likely to account, at least in part, for the enhanced rates of liver protein turnover that characterize hepatic involution.

Animals↗
PubMed1989

Desmoplastic fibroma of the mandible: a case with an unusual clinical presentation.

A new case of desmoplastic fibroma of the mandible is reported. The patient was a 29-year-old woman who presented with a 5-year course of abscess-like lesions simulating a chronic apical infection. Radiographically, a nonspecific, small osteolytic area was observed. A wide resection of the tumor and the neighboring bone was performed.

Adult↗
PubMed1989

[Phenotype study of varieties of carcinomas originating in the oro-pharyngo-laryngeal mucosa. Anatomo-clinical considerations].

An immunohistological analysis with a panel of monoclonal and polyclonal antibodies was performed in 20 cases of squamous cell carcinoma originating in the oral cavity, oropharynx and larynx. The epithelial antigens were detected in all cases with variable patterns of positivity: cytokeratins and epithelial membrane antigen were positive in a high number of neoplastic cells in the carcinomas with a high grade of differentiation, whereas a lesser number of positive cells was observed in the poorly differentiated carcinomas. On the contrary the tissue polypeptide antigen was detected in a considerable number of neoplastic cells in the poorly differentiated carcinomas as well as in the fields with basal and cylindric cells. Mesenchymal antigens were negative in all tumors, except one case with pseudosarcomatous patterns, which was vimentin-positive. The detection of an immunohistochemical spectrum of squamous cell carcinomas may give further information on the biological characteristics, and consent to identify subtypes with a different histogenesis.

Aged↗
PubMed1988

Immunohistochemical assessment of ferritin in bone marrow trephine biopsies: correlation with marrow hemosiderin.

In 340 bone marrow biopsies we compared ferritin, stained with an immunoperoxidase method, with hemosiderin, stained with Perls' reaction. Ferritin and hemosiderin showed the same distribution in reticuloendothelial cells. All the Perls-positive cases (n = 177) were ferritin-positive too. None of the ferritin-negative cases (n = 13) were Perls-positive. Of 163 cases with negative Perls' reaction in bone marrow, 13 (12.5%) were also ferritin-negative: these patients were mainly affected by polycythemia vera or by untreated iron deficiency anemia. Thus, immunohistochemical assessment of bone marrow ferritin can be a more sensitive tool for the evaluation of body iron stores in iron deficiency than Perls' reaction.

Biopsy↗
PubMed1987

Relationship between structure and T-lymphocyte maturation in human thymomas. Enzyme histochemical and immunohistological studies.

Twenty-six human thymomas were studied in an attempt to correlate their morphological appearance with the type and degree of T-lymphocyte maturation, as determined by acid alpha-naphthyl-acetate esterase (ANAE) activity and immunological analysis. Four normal human thymuses were used for purposes of comparison. Two morphological patterns were identified in the thymomas. The distinction was based largely on similarities between the neoplastic epithelial cells and normal cortical and medullary epithelial cells, and on the relative proportions of epithelial cells and lymphocytes. By these criteria "medullary" and "cortical" patterns were identified. In several thymomas both patterns were present in the same tumor ("mixed-type pattern"), producing alternating dark cortical-like areas and lighter foci of medullary differentiation. A good correlation was found between the two patterns and the phenotype of the T-associated lymphoid component. ANAE activity, which was completely lacking in normal cortical thymocytes, was almost absent in the phenotypically immature T-cells of cortical-type thymomas. By contrast, in the medullary-type thymomas, T-cells showed immunological features in common with medullary thymocytes. This was characterized by strong ANAE activity in the majority of cells with a staining pattern corresponding to that of peripheral T-lymphocytes. In addition, most of the proliferating epithelial cells in medullary-type thymomas stained strongly with anti-cytokeratin and anti-epidermal-type keratin antisera. In the mixed-type thymomas the epithelial cell morphology and the immunohistochemical and enzymic features of the T-cells were found to be closely related to the respective cortical--or medullary-like areas. It was concluded that the various characteristics of normal thymic cortex and medulla studied are also present in thymomas. In particular, in medullar-type thymomas the presence of many of the features of normal thymic medulla, such as a squamous cell component, macrophages and interdigitating reticulum cells, may constitute a microenvironment which operates actively in T-cell education. This may account for the functional activities, characteristic of peripheral T-lymphocytes, which T-lymphocytes attain in these thymomas.

Adult↗
PubMed1987

[Use of the monoclonal antibody KI-67 in the study of the proliferative activity of urologic tumors. Preliminary data].

The authors report the preliminary data of a study on the proliferative activity in urologic cancers. They use the monoclonal antibody KI-67 which can find out a nuclear antigen present only in cells in proliferative phase. They describe the methodology and report the results concerning 12 cancers of the kidney, 17 of the bladder, 17 of the prostate and 2 of the testicle. The most interesting results were obtained in the study of bladder cancer where they could pick out, in the context of the cancers with grading G2, a sub-group with proliferative characteristics similar to those of cancers G3 and vice-versa. They also obtained important results in the study of prostate cancer in hormonal therapy, as they could demonstrate the disappearance of the proliferative activity in patients responding clinically to the treatment.

Animals↗
PubMed1987

[Radiologic aspects of myxoma of the jaws].

Four cases of jaw bones myxoma are described, laying special stress on the radiological appearance. Conventional radiogram showed a typical multilocular osteolytic lesion thinning and expanding the cortical bone. This allowed the authors to correctly diagnose the affection. On the contrary CT, showing a unilocular lesion, offered a far less typical representation of the tumor in the two patients who underwent this examination.

Adolescent↗
PubMed1983

Prominent plasmacytic differentiation in the recurrence of a parotid immunocytoma. A morphologic and immunohistochemical study.

We report and discuss a case consisting of 2 lesions that developed at different times in the same parotid gland. Although the first lesion showed morphologic features similar to those of the benign lymphoepithelial lesion, a monotypic IgM/K pattern was also revealed by the immunoperoxidase method in its lymphoid infiltrates. Thus, on cytologic grounds, the first lesion was classified as lymphoplasmacytic immunocytoma (according to Kiel criteria). In the second lesion, which recurred 3 years later, the prominent feature was a marked predominance of plasma cells with the same monoclonal IgM/K as the preceding lymphoma. These findings suggests that a B-lymphomatous cell monoclone may undergo morphologic maturation along the lineage of its competence. Secondly, they indicate that every case of benign lymphoepithelial lesion of the salivary glands should undergo thorough immunologic evaluation to exclude the possibility of signs of precocious lymphomatous transformation.

Adult↗