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Biomedical subjects

G Zamboni

Publications and source records attributed to G Zamboni.

At least 145 records · Page 8Linked to original sources
PubMed1990

Small-cell neuroendocrine carcinoma of the ampullary region. A clinicopathologic, immunohistochemical, and ultrastructural study of three cases.

We report the clinicopathologic, immunohistochemical, and ultrastructural features of three small-cell neuroendocrine carcinomas of the ampullary region of the duodenum. All patients were men; their ages were 51, 62, and 66 years. The therapy consisted of pancreatoduodenectomy. All patients died of the disease; median survival was 10 months from the diagnosis. The histological appearance was identical to pulmonary and extrapulmonary small-cell carcinoma. The neuroendocrine differentiation was demonstrated ultrastructurally by the presence of dense-core granules, and by the positive immunoreaction for neuron-specific enolase and Leu-7 in each case. One case expressed a focal positivity for chromogranin A (PHE-5) and argyrophilic granules. The same case showed the presence of neurofilaments on frozen material. Neurofilament proteins could not be demonstrated in any case in paraffin sections. Neoplastic cells exhibited cytoplasmic immunostaining for cytokeratins (CAM 5.2) in all cases. In one case, a large number of neoplastic cells (60-70%) exhibited nuclear Ki-67 positivity. We postulate that the disease's histogenesis was from epithelial stem cell expressing both epithelial and neuroendocrine characteristics. The clinical behavior of small-cell neuroendocrine carcinomas of the ampullary region appears to be extremely aggressive, with early metastases and fatal outcome.

Adenocarcinoma↗
PubMed1990

Immunocytochemical localization of progesterone receptors in endocrine cells of the human pancreas.

Progesterone receptors (PgR) have been immunocytochemically localized in the nuclei of several (40% to 75%) endocrine cells of the human pancreas and in a more variable number of neoplastic cells of 7 of 18 endocrine pancreatic tumors. Conversely the exocrine epithelial cells of the pancreas did not exhibit any PgR immunoreactivity in normal as well as in different pathologic conditions, including pancreatic adenocarcinomas. Estrogen receptors were not detected in any of the pancreatic samples investigated. Double immunocytochemical experiments have documented that PgR immunoreactivity in normal Langerhans islets is a consistent feature of most (75%) glucagon-producing A cells, of approximately 5% to 20% of insulin-producing B cells, and of a variable percentage of pancreatic polypeptide (PP)-producing cells, ranging from 5% to 70%. These figures were not affected by the sex, age, or underlying disease of the patients. The reported findings corroborate previous clinical and experimental evidence indicating that sex steroid hormones may have some regulatory effects on the functional activity of the endocrine pancreas.

Adolescent↗
PubMed1989

Terminal deletion of the long arm of chromosome 10: case report and review of the literature.

We report on a newborn girl with a terminal deletion of the long arm of chromosome 10: del (10)(pter----q26). The phenotypic manifestations are compatible with those of the previously reported cases. In addition, the association with abnormalities of the urinary tract is reported for the first time. A clinical and neurodevelopmental follow-up is described up to age 18 months.

Chromosome Aberrations↗
PubMed1989

Breast carcinoma with positive results for melanoma marker (HMB-45). HMB-45 immunoreactivity in normal and neoplastic breast.

HMB-45 (melanocytic cell-specific monoclonal antibody) immunoreactivity has been detected by the immunoperoxidase technique in the cytoplasm of 2 of 100 breast carcinomas. In addition, normal breast lobules and ducts were occasionally found to have positive results in 6 of 100 cases. These findings indicate the need to exercise caution in the interpretation of HMB-45 immunoreactivity for immunohistochemical characterization of neoplasms.

Antibodies, Monoclonal↗
PubMed1989

Monomeric calcitonin secretion in infants with congenital hypothyroidism.

We have determined CT levels in whole serum (iCT) and by an extraction method (exCT) in 25 infants affected by congenital hypothyroidism (CH)--11 athyreotic and 14 dysgenetic--at age 25 days, before the institution of therapy, and at age 2 years. In hypothyroid patients at age 25 days the iCT and exCT levels were similar to those found in controls of the same age. At age 2 years the iCT and exCT levels decreased in both groups of patients. However, whereas the levels of iCT in hypothyroids were similar to those found in controls of the same age, the levels of exCT were significantly lower in hypothyroids than in controls; moreover they were significantly lower in athyreotic than in dysgenetic patients. At this age, after calcium infusion, exCT levels significantly increased in dysgenetic but not in athyreotic patients. We hypothesize that CT deficiency in CH is due to increased degradation of human CT by the substitutive therapy, which, stimulating proteolytic enzymes, destroys the biologic activity of CT. An extraction procedure improves the sensitivity and specificity of the CT assay and it must be used when CT deficiency is suspected. In addition we suggest that the measurement of exCT levels after Ca infusion might be useful to distinguish dysgenetic from athyreotic patients.

Calcitonin↗
PubMed1989

Pancreaticoduodenal graft in the rat: an original microsurgical technique.

The authors describe an original surgical technique for pancreatic transplantation carried out on an experimental rat model which duplicates as closely as possible the anatomic-functional situation of a pancreatic graft in man (one arterovenous vascular peduncle with one functioning kidney only). The technique entails a microanastomosis between the mesenteric artery and the portal vein of the donor organ with the left renal artery and vein of the recipient. This method appears to be technically encouraging and particularly useful in studying the early phases of ischemic graft injuries, a field in which the authors are particularly interested.

Animals↗
PubMed1989

The effect of propranolol on cAMP concentration in the rat preoptic region during the wake-sleep cycle.

In control conditions preoptic cAMP concentration during wakefulness was significantly higher than during synchronized sleep. No differences in nucleotide concentration were observed in the cerebral cortex. Propranolol decreases brain cAMP concentration. This change was associated with the suppression of the difference observed between wakefulness and synchronized sleep in the preoptic region.

Activity Cycles↗
PubMed1989

[Deep interscapular temperature and thermogenesis of brown fat during sleep].

Deep interscapular temperature measured just below the brown fat lobes was studied in rats during sleep at two ambient temperatures (24 degrees C and 4 degrees C) before and after adaptation (9 days) to cold (4 degrees C). The results show that in the cold ambient deep interscapular temperature decreases during desynchronized sleep independently of adaptation. Such change in temperature is probably the result of the depression in sympathetic vasoconstrictor influences on heat exchangers producing blood and brown fat cooling in sequence during this stage of sleep.

Adipose Tissue, Brown↗
PubMed1989

[Hypothalamic temperature and thermogenesis of brown fat during desynchronized sleep in rats].

The relationship between hypothalamic temperature and deep interscapular temperature measured just below the brown fat lobes has been studied during desynchronized sleep at two ambient temperatures (24 degrees C and 4 degrees C) before and after adaptation (9 days) to cold (4 degrees C). The results show that the increase in hypothalamic temperature during this stage of sleep occurs independently of a transfer of heat from interscapular brown fat.

Adipose Tissue, Brown↗
PubMed1988

Distribution of melanoma specific antibody (HMB-45) in benign and malignant melanocytic tumours. An immunohistochemical study on paraffin sections.

The distribution of a recently produced melanoma specific antibody (HMB-45) has been evaluated histochemically on paraffin sections in a large panel of melanocytic and non melanocytic tumours. Results have been compared with the presence of S-100 protein. HMB-45 was shown to be a highly specific antibody being present only in melanomas, junctional melanocytes and histogenetically related neoplasms such as melanocytic neuroectodermal tumour of infancy and, at low levels, on a proportion of peripheral nerve sheath tumours. The high specificity of HMB-45 antibody, coupled with the greater sensitivity of S-100, makes the combined use of these markers practical in the differential diagnosis of skin tumours and of metastatic lesions of uncertain primary site.

Antibodies, Neoplasm↗
PubMed1988

Mineral metabolism in obese children.

Blood levels of glucose, insulin (IRI), Calcium (Ca), phosphorus (P), alkaline phosphatase (AP), osteocalcin (OC), parathyroid hormone (PTH), calcitonin (CT), 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and urinary excretion of Ca (Ca/Cr), P (TmP/GFR), hydroxyproline (OH-P/Cr) and cyclic AMP (cAMP/GFR) were determined in 16 obese children, aged 8 to 11 years, on a diet rich in calories and carbohydrates and in 15 controls of the same age. Blood glucose, IRI, Ca, P, PTH and CT were also determined in both groups of subjects, during an oral glucose tolerance test (OGTT). In basal conditions glucose, IRI, AP, OC, PTH, CT and 1,25(OH)2D3 levels were significantly higher, and 25OHD3 levels lower, in obese children than in controls. Urinary Ca/Cr, TmP/GFR were lower in obese than in non obese children, while OH-P/Cr and cAMP/GFR were higher. Bone mineral content (BMC), measured by photon absorptiometry, and BMC/bone width ratio were lower in obese than in non obese children. During OGTT serum Ca and P decreased and serum PTH and CT increased less in obese than in non obese children. In obese children receiving a diet with high carbohydrate content, an alteration of mineral metabolism occurred, characterized by secondary increase of PTH and 1,25(OH)2D3. Ca decreased and PTH and CT increased less markedly during OGTT.

Alkaline Phosphatase↗
PubMed1987

Mediastinal large-cell lymphoma with sclerosis. Genotypic analysis establishes its B nature.

The Southern blot hybridization technique has been applied to study the configuration of immunoglobulin and T-cell receptor genes in 6 cases of the so called mediastinal large cell lymphoma with sclerosis. This lymphoma has been recently recognized as a separate entity among non-Hodgkin lymphomas mainly affecting young adult patients. The B-cell origin of this neoplasm was suggested by means of immunohistochemical analysis. However, the immunophenotypical B-cell related markers used do not always exhibit lineage fidelity. The Southern blot analysis demonstrated the presence of unique heavy and k-light chain immunoglobulin gene rearrangements, establishing genotypically their B-cell origin.

B-Lymphocytes↗