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Biomedical subjects

G Massarelli

Publications and source records attributed to G Massarelli.

At least 55 records · Page 3Linked to original sources
PubMed1992

Chemoprevention of rat liver carcinogenesis by S-adenosyl-L-methionine: a long-term study.

Previous work has shown a consistent fall in S-adenosyl-L-methionine (SAM) in the liver of diethylnitrosamine-initiated rats, during the development of preneoplastic lesions, in persistent nodules (PNs), and hepatocellular carcinomas. The injection of SAM into rats causes the reconstitution of the SAM pool, coupled with growth restraint, remodeling, and apoptosis of preneoplastic cells, and inhibits the development of PNs and hepatocellular carcinomas. To evaluate if SAM treatment causes a long-term prevention of preneoplastic and neoplastic liver lesions or merely causes a delay in their development, we evaluated the effect of a relatively short SAM treatment on the development of preneoplastic and neoplastic lesions in a long-term study. Male Wistar rats were subjected to initiation with diethylnitrosamine, followed by selection and then by the administration of phenobarbital for 16 weeks. After selection, the rats were given i.m. injections of a purified SAM preparation (384 mumol/kg/day) for 24 weeks. In SAM-treated rats, a decrease in the incidence of PNs was found 6, 14, and 24-28 months after initiation. At the end of SAM treatment the number of PNs per rat liver, nodule diameter, and labeling and mitotic indices of nodular cells decreased considerably in control rats. Nodule diameter started to increase rapidly again only 8 months after arresting SAM treatment, when complete recovery of DNA synthesis in nodular cells occurred. The majority of nodules present in the liver 6-28 months after initiation belonged to the clear and acidophilic cell types, with lower percentages of mixed cell and basophilic cell types. A decrease in basophilic nodules occurred in SAM-treated rats. Fourteen and 24-28 months after initiation hepatocellular carcinoma incidence was 11 of 12 and 10 of 10 in control rats, respectively, and only 1 of 12 and 3 of 11 in SAM-treated rats. At the 24th-28th month all control rats had tumors identified as 2 poorly differentiated carcinomas, 6 trabecular carcinomas, or 3 adenocarcinomas, while only 2 relatively small trabecular carcinomas and 1 small glandular tumor developed in SAM-treated rats. In 3 of 11 SAM-treated rats, but in none of the control rats, leukemic infiltration of liver occurred 24-28 months after initiation. Leukemic infiltration of the spleen occurred in 5 and 3 control and SAM-treated rats, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Scanning electron microscopic features of Kaposi's sarcoma.

In order to clarify the three-dimensional structure of Kaposi's sarcoma (KS) five cases of KS of the skin were observed with a scanning electron microscope (SEM). KS lesions were investigated both in vascular and spindle cell areas and were compared with similar areas observed by light microscopy. KS appears as a spongelike neoplasm consisting of irregular vascular channels lacking endothelial cells and well-developed basement membranes. Vascular spaces and vascular slits are packed with numerous red blood cells (RBCs). SEM features of KS share some similarities with those of hemangiopericytoma, a vascular tumor composed of mature endothelial cells surrounded by pericytes. These findings are consistent with the hypothesis according to which the proliferating cells of KS are viewed as immature endothelial cells with partial differentiation into pericytes.

Cell Division↗
PubMed1989

Immunocytochemical profile of Kaposi's sarcoma cells: their reactivity to a panel of antibodies directed against different tissue cell markers.

Thirty-three cases of European Kaposi's sarcoma (KS) were investigated by immunohistochemical methods using a panel of antibodies specific for the markers of the cell types proposed for its histogenesis in the literature: S-100 protein for Schwann cells; lysozyme for histiocytes; alpha-actin, desmin and vimentin for pericytes and other mesenchyme-derived cells; factor VIIIR:Ag and Ulex europaeus agglutinin-I for endothelial cells. Antifibronectin antibodies were also used in order to investigate some functional activities of the proliferating cells. Immunohistochemical results showed that KS cells were diffusely positive for vimentin and alpha-actin and negative for all other cell markers. Furthermore, KS cells were constantly surrounded by fibronectin-positive material. Since the KS cells are diffusely positive for vimentin, they may be considered a monotypic proliferation of mesenchyme-derived cells which lack the markers of full endothelial cell differentiation; however, the occurrence of fibronectin-positive material around them suggests that these cells are actively proliferating endothelial cells and their diffuse positivity for alpha-actin suggests a possible differentiation to pericytic cells. In conclusion KS cells may be considered as mesenchymal cells which are at an intermediate stage of maturity or immaturity in vascular differentiation.

Actins↗
PubMed1989

Hyaline bodies in Kaposi's sarcoma: an immunocytochemical and ultrastructural study.

The nature of hyaline bodies (HB) in Kaposi's sarcoma (KS) has been investigated by electron microscopy (EM) and immunohistochemical methods. Paraffin sections from 45 cases of KS selected on the basis of their high content of HB were challenged with antisera against factor VIIIR:Ag, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), alpha 1-antitrypsin (A1AT), fibrinogen, hemoglobin, alpha-actin and lysozyme. HB showed positivity for all the antibodies except for the last two. By EM, HB showed features consistent with red blood cell, fibrin and platelet phagocytosis. Therefore, HB in KS are considered to be the expression of an indiscriminate process of phagocytosis which involves not only erythrocytes and platelets, but also other substances such as fibrinogen, factor VIIIR:Ag, A1AT, CEA and AFP.

Antibody Specificity↗
PubMed1988

Angiosarcoma of the thyroid: a light, electron microscopic and histoimmunological study.

A histologic, histoimmunological, and ultrastructural study of a primary angiosarcoma of the thyroid gland is reported. The occurrence of neoplastic cells positive for Factor VIII-related antigen and Ulex Europaeus Agglutinin-I and the presence in their cytoplasms of Weibel-Palade bodies are consistent with this diagnosis. These findings further support the view that primary angiosarcoma of the thyroid is a distinct pathological entity and should no longer be interpreted as a variant of a poorly differentiated carcinoma.

Aged↗
PubMed1988

Photodynamic therapy of malignant brain tumors: clinical results of, difficulties with, questions about, and future prospects for the neurosurgical applications.

Photodynamic therapy (PDT) has been applied in a variety of oncological fields with good results. In neurosurgery, the clinical series are limited and the number of treated patients is not statistically significant. This work examines the results of PDT performed in our clinic and discusses some difficulties and causes of failure of this method in neurosurgical patients. Eight patients with malignant brain tumors underwent PDT. All had been treated previously by operation and radiation therapy and one patient had also received chemotherapy. At 24 hours after the i.v. injection of hematoporphyrin (5 mg/kg body weight), the tumor was removed as radically as possible and the residual tumor bed was exposed to either 630-nm light from an argon-dye laser or 600- to 680-nm light isolated from the emission of a quartz-halogen lamp. The type of sensitizer, the irradiation methods, and the peculiarities of glial tumors are examined as possible causes of failure. The longer survivals of some patients with glial tumors treated by PDT may make this treatment suitable when traditional therapies fail.

Adult↗
PubMed1988

Maxillary chondrosarcoma (report of two cases).

Two cases of chondrosarcoma of the maxilla are reported together with the clinical and histological differential diagnosis. The origin of this rare tumour in the maxilla, a bone with exclusive membranous ossification, is discussed in accordance with the new concept of cell differentiation in neoplasia.

Adult↗
PubMed1987

Vimentin-typing in diagnostic surgical pathology: a comparative study using four antibodies after different fixations.

Vimentin-typing was carried out on various normal and neoplastic tissues using four anti-vimentin antibodies in order to evaluate the effect of different fixation treatments on tissue reactivity in comparison to the results obtained on frozen sections. All antisera were reactive on frozen material; on paraffin embedded material staining of tissues depended on the type of fixation method applied (formalin, methacarn or absolute alcohol) and each antibody behaved differently in relation to the fixative used. Only mesenchymal normal structures were revealed on frozen material whilst on paraffin embedded material three of the four antibodies reacted also with non-mesenchymal normal structures (epithelia, central and peripheral nervous system cells). All four antibodies decorated, regardless of treatment, neoplastic cells of mesenchymal and non-mesenchymal derivation, but not germ cells or germ cell tumors. The reactivity of vimentin to its specific antibodies depends on the fixative used: therefore, in routine pathology more than one antiserum should be available for testing. Furthermore, given the variety of non-mesenchymal structures stained by the anti-vimentin antibodies, the differential diagnosis of undifferentiated tumors must not be based on vimentin positivity alone. The expression of vimentin by non-mesenchymal neoplastic cells seems to parallel that of normal tissues during embryogenesis; therefore, this intermediate filament appears to be not only a marker of mesenchymal cells but also of many immature elements.

Antibodies, Monoclonal↗
PubMed1987

Female genital cancer incidence in the Province of Sassari from 1974 to 1983.

The incidence of gynaecologic tumours in the Province of Sassari has been studied in order to estimate their value and to make a comparison with the ones industrialised countries. The global incidence of uterine cancer (corpus uteri plus cervix) is of 18.16/100,000 women; 11.99/100,000 for cancers of corpus uteri and 6.17/100,000 for cervical carcinoma including in situ forms. The incidence of gynaecologic tumors for the District of Sassari is equivalent to that reported in Western countries and it does confirm indeed a constant and progressive increase in tumours of the corpus uteri and a reduction in cervical carcinoma especially if in situ forms are excluded.

Adolescent↗
PubMed1983

Multicentric giant lymph node hyperplasia: an immunohistochemical study.

Biopsy specimens from five cases of multicentric giant lymph node hyperplasia were studied by standard histochemical techniques and by immunoperoxidase staining and double immunoenzyme labeling to determine the distribution of intracytoplasmic immunoglobulins and kappa and lambda light chains. Microscopically, the affected lymph nodes showed a nodular pattern characterized by multiple lymphoid follicles permeated by numerous small vessels. A striking proliferation of post-capillary venules with many plasma cells and immunoblasts was observed in the interfollicular areas. Immunoperoxidase staining revealed that the cells were positive for IgG, IgA, and IgM with both kappa and lambda chains in the normal ratio. The IgM-positive cells had a perifollicular distribution, whereas the IgG- and IgA-positive cells were located mainly in interfollicular areas. The presence and distribution of different classes of intracytoplasmic immunoglobulins seemed to reflect a normal, albeit tumultuous, immunologic response. Therefore, the disease can be considered a lymphoproliferative disorder due to an inappropriate immunologic reaction.

Aged↗
PubMed1983

A systemic lymphoproliferative disorder with morphologic features of Castleman's disease. Pathological findings in 15 patients.

This report describes the nodal and extranodal lesions observed in 15 patients with a generalized disorder that had been histologically diagnosed as Castleman's disease. The disorder was characterized by severe constitutional symptoms, constant involvement of multiple peripheral lymph nodes, and frequent hepatosplenomegaly, in association with clinical and laboratory features reminiscent of a "collagen disease." The clinical course was chronic, with remissions and exacerbations in seven patients, and aggressive and fatal in eight. The material examined included multiple lymph node biopsies, four surgical specimens of spleen, one open lung biopsy, and material from four autopsies. The diagnostic morphological findings were observed in the nodes and were represented by the following histologic triad: diffuse marked plasmacytosis, from the medulla to the subcapsular areas; prominence of the germinal centers; and good preservation of the architecture. One variant of this basic pattern featured abundant immunoblasts and blood vessels. The process appears to be a systemic reactive proliferation of B-lymphocytes, perhaps resulting from faulty immune regulation. Morphologic similarities indicate a relationship between this multicentric disorder and Castleman's disease of plasmacellular type. However, there are distinct differences between them in clinical presentation and evolution, and, consequently, in therapeutic approach.

Adult↗
PubMed1983

Myofibroblasts in the epithelial-stromal junction of basal cell carcinoma.

The epithelial-stromal junction of basal cell carcinoma (BCC) has been investigated at the electron microscope level. The fibroblast-like cells surrounding the epithelial nests of BCC appear to be myofibroblasts. According to the present view of the function of myofibroblasts, their presence around BCC could be related to the slow invasiveness of this tumour.

Basal Cell Carcinoma↗
PubMed1982

Primary Kaposi's sarcoma and Hodgkin's disease in the same lymph node.

The occurrence of primary Kaposi's sarcoma in a lymph node affected by Hodgkin's disease is reported. The case concerns a 43-year-old woman with a recurrence of Hodgkin's disease 13 years after its initial diagnosis. In one of four excised supraclavicular nodes a Kaposi's sarcoma was unexpectedly found. The present observation stresses once more that the two diseases are closely related and possibly share the same pathogenesis.

Adult↗
PubMed1980

Haemangiopericytoma of the parotid gland. Report of a case and review of the literature.

A primary malignant haemangiopericytoma of the parotid gland is reported. Microscopically the tumour showed two different types of area: in the first a histologically benign haemangiopericytoma was present, in the second, separated from the former by a clear-cut border, the structure was that of a histologically malignant haemangiopericytoma which subsequently metastasized and killed the patient. The report stresses the great rarity of this neoplasm in the parotid gland and discusses the problem of the behaviour of haemangiopericytomas.

Hemangiopericytoma↗
PubMed1980

Multicentric giant lymph node hyperplasia. A hyperimmune syndrome with a rapidly progressive course.

A patient who had diffuse lymph node enlargement, fever, skin rashes, anemia and polyclonal hypergammaglobulinemia is described. Histologic examination of lymph nodes taken from different sites (cervical, axillary and inguinal) revealed the presence of giant lymph node hyperplasia. The liver and bone marrow showed a moderate lymphocytic and plasma cell infiltration. The clinical presentation of a multicentric variety of giant lymph node hyperplasia in the reported case is similar to the clinical features usually associated with angio-immunoblastic lymphadenopathy with dysproteinemia, indicating that these two disorders may be related and may affect the same organs and systems. Alternatively, this histologic reactive giant lymph node hyperplasia progressing with a rapid declivitous course can be considered distinctive of a separate entity.

Aged↗
PubMed1979

Acute agnogenic myeloid metaplasia with chromosomal abnormalities.

A case of a 37-year-old woman presenting with acute agnogenic myeloid metaplasia (AAMM) is described. The disease had a stormy course and was characterized by moderate splenomegaly, persistently depressed WBC counts, extramedullary hemopoiesis and presence of a high percentage of atypical myeloblasts in the peripheral smear. Platelets were persistently low, reticulocytes significantly below normal, notwithstanding anemia. Hot tended to fall progressively to intolerably low values in the absence of transfusion. The chromosomal mapping of peripheral blood revealed the presence of a trisomy of chromosome No. 8. This abnormality already demonstrated in two previous cases of acute myelofibrosis and the clinical course of the disease suggest that acute myelofibrosis and AAMM could be the same disease while chronic myelofibrosis should be considered a separate entity. Also, it is possible that AAMM with trisomy of chromosome No. 8 and stormy clinical course may be a different entity from the acute myeloproliferative disorders associated with other chromosomal abnormalities.

Acute Disease↗