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Biomedical subjects

L Lombardi

Publications and source records attributed to L Lombardi.

At least 109 records · Page 6Linked to original sources
PubMed1983

Immunohistochemistry and electron microscopy of intravascular bronchioloalveolar tumor of the lung.

We report on an intravascular bronchioloalveolar tumor (IVBAT) detected in the lungs of a 45-year-old female. The results of the immunohistochemical and ultrastructural investigations stress the already suggested endothelial origin of the tumor. The clinical and histopathologic differential diagnoses between IVBAT and other rare tumors of the lung are discussed. Similarities of IVBAT with other more or less recently described endothelial tumors of the liver, skin and soft tissues are pointed out.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1983

Plasma and urine cyclic nucleotide levels in patients with hyperthyroidism and hypothyroidism.

Plasma levels and 24-h urinary excretion of cyclic AMP and cyclic GMP were measured in 18 patients with hyperthyroidism, 7 patients with hypothyroidism and 25 normal subjects. Mean plasma and urinary levels of both cyclic AMP and cyclic GMP were significantly positive correlations between the serum thyroid hormone levels and plasma and urinary cyclic nucleotide concentrations were also found, suggesting that the elevated extracellular cyclic nucleotide levels in hyperthyroidism are probably a consequence of increased secretion of thyroid hormones. In the hypothyroid patients the extracellular cyclic nucleotide concentrations did not differ significantly from those of the normal subjects.

Adolescent↗
PubMed1983

Plasma and urine cyclic nucleotide levels in patients with acute and chronic leukemia.

Plasma and urine levels of cyclic adenosine 3',5'-monophosphate (cAMP) and of cyclic guanosine 3',5'-monophosphate (cGMP) were measured in 35 normal subjects, in 24 patients with nonneoplastic diseases (iron deficiency anemia, peptic ulcer, and cholelithiasis), and in 50 leukemic patients. The leukemic group included patients with acute lymphoblastic leukemia, acute myelogenous leukemia, chronic lymphocytic leukemia, and chronic myelogenous leukemia. All patients were recently diagnosed and untreated, except for 5 patients with blastic transformation of chronic myelogenous leukemia who had been previously treated. There were no significant differences in plasma and urine cyclic nucleotide levels between normal subjects and patients with nonneoplastic diseases. In leukemic patients, plasma and urine cAMP levels were similar to those of normal subjects, whereas plasma and urine cGMP levels were markedly elevated. There were no significant differences in cGMP values between the various types of leukemia. After starting treatment, plasma cyclic nucleotide levels were periodically measured in 21 of the patients with acute leukemia; cGMP levels were normalized in all the 16 subjects who attained complete remission, whereas both cAMP and cGMP levels were apparently unaffected in the patients who did not respond to treatment. This suggests that plasma or urine cGMP could be used as an additional parameter to monitor the patient's response to treatment.

Acute Disease↗
PubMed1982

Neuroendocrine (Merkel cell) carcinoma of the skin.

Merkel cell carcinoma was diagnosed in 10 patients (eight females and two males) with a mean age of 66 years and a range of 44-84. The most common sites of the primary tumor were the skin of the limbs, girdles, and head. Sixty percent of the cases had recurrences and 50% regional nodal metastases that appeared within 1 year. Of the patients treated variably with surgery, chemotherapy, and radiotherapy and followed for a mean period of 28 months, two were alive and free of disease, two were alive with disease after 3 and 6 years, and two have died of metastatic disease to the lungs and liver. The primary lesions showed quite distinctive clinical and gross features in terms of size, shape, and color. Histologically, the growth was usually diffuse and occasionally trabecular or pseudoglandular; infiltration was predominantly in the papillary and reticular dermis. The uniform, poorly cohesive cells contained argyrophilic granules in the cytoplasm and round to oval nuclei with frequently indented membranes. The mitotic index was high. Ultrastructurally, in two cases, two cell types were identified that probably represented the neoplastic counterpart of normal Merkel cells in different stages of maturation. Both cell types contained cytoplasmic neurosecretory granules and intermediate filaments, even though their cytoplasms were differently shaped.

Adenocarcinoma↗
PubMed1982

Growth pattern of the human promyelocytic leukaemia cell line HL60.

In order to characterize the growth pattern of the human promyelocytic leukaemia cell line HL60, its kinetic parameters were studied. The doubling time was calculated from serial cell counts, the duration of the various cell cycle phases from the analysis of the labelled mitoses curve, and quiescent population from continuous labelling experiments. Proliferation in culture was exponential up to a saturation density of about 3.0 x 10(6) cells/ml, with a doubling time of 34.0 hr. The cell cycle duration was 24.3 +/- 4.1 hr (SD), and that of the cell cycle phases was: G1, 3.8 +/- 2.2 hr; S, 15.1 +/- 3 hr; and G2, 4 +/0 1.2 hr. The growth fraction was 0.85, and cell loss was restricted to the quiescent cells. The HL60 cell line, with fully characterized kinetics, provides a useful tool for the vitro study of substances which may affect human leukaemic myelopoietic proliferation.

Animals↗
PubMed1982

Effect of granulocytic chalone on the growth rate of continuous cell lines propagated in vitro: a new assay system.

The progress of research on granulocytic chalone has been hampered by a lack of reliable assay systems. This paper reports the use of continuous cell lines growing in liquid suspension culture as a new method for assessing the effect of granulocytic chalone on cell proliferation. Partially purified granulocytic chalone (PPGC) was added to cultures of a rat myeloid cell line (W25), a human myeloid cell line (HL60), a human B lymphocytic cell line (8392), and a human T lymphocytic cell line (8402). The growth rate of the target cell populations was directly assessed by serial cell counts. PPGC pretreatment resulted in a significant inhibition of cell proliferation of the 2 myeloid permanent cell lines, while the growth rate of the lymphocytic cell lines was not affected. Moreover, inhibition of cell proliferation was spontaneously reversed when PPGC treatment was discontinued. Since PPGC from ox leucocytes displayed an inhibitory effect on cell proliferation which was specific to the myeloid cells, spontaneously reversible and not species-specific, it appears to have all the essential properties of a granulocytic chalone.

Animals↗
PubMed1980

Patterns of cyclic nucleotides in normal and leukaemic human leucocytes.

Because recent observations indicate that metabolism of cyclic nucleotides may be altered in neoplastic cells, the intracellular levels of cyclic adenosine 3',5'-monophosphate (cAMP) and cyclic guanosine 3',5'-monophosphate (cGMP) were measured in mononuclear leukaemic and normal human leucocytes. The activities of adenylate cyclase, guanylate cyclase and cyclic nucleotide phosphodiesterases were also determined. Under basal conditions, cAMP levels were always higher in the normal leucocytes, whilst cGMP levels were of the same order of magnitude in both normal and leukaemic cells, causing the cAMP/cGMP ratios to be significantly lower in leukaemic leucocytes. Leukaemic cells significantly increased cyclic nucleotide levels in response to theophylline, but did not respond to serotonin, carbamylcholine or D,L-isoproterenol. Preincubation of these leucocytes with theophylline produced a detectable cAMP response to D,L-isoproterenol but no cGMP response to serotonin or carbamylcholine was found. Adenylate cyclase and guanylate cyclase were significantly lower in leukaemic than in normal cells, which could largely explain the abnormal cyclic nucleotide pattern found in human leukaemic leucocytes. In our experiments, cAMP phosphodiesterase activity was comparable in normal and leukaemic cells, whereas cGMP phosphodiesterase activity was undetectable inall mononuclear-leucocyte preparations with the methods used.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1979

Unusual morphologic features of a primary liver neoplasm.

Light and electron microscopy study of an unusual primary liver neoplasm observed in a 36-year-old woman. By light microscopy the tumor, initially detected by a needle biopsy and later surgically removed, was mainly composed of spindle-shaped and multinucleated cells which were similar to rhabdomyoblasts. These cells, however, showed ultrastructural features of hepatocytes.

Adult↗
PubMed1978

Hairy cell leukemia: enzyme-histochemical and ultrastructural investigation of one case.

The investigation was carried out on blood smears, bone marrow aspirates, one lymph node biopsy, and the surgically removed spleen of a 53-year-old man with hairy cell leukemia. In the blood smears stained with May-Grünwald-Giemsa, 60 to 70% of the hairy cells contained tubular inclusions that corresponded to the ribosome-lamella complexes demonstrated at electron microscopy. In blood smears, imprints and cryostatic sections of the lymph node and of the spleen, hairy cells revealed tartrate-resistant acid phosphatase, beta-glucuronidase and adenosine-triphosphatase activity. In the spleen neutral esterase and alkaline phosphatase demonstrated the numerical increase of the histiocytes, which ultrastructurally displayed phagocytic activity. The presence in the spleen of pseudosinuses lined by hairy cells was confirmed by electron microscopy as well as by cytoenzymology.

Blood Cells↗
PubMed1978

Malignant histiocytosis: a histological and ultrastructural study of lymph nodes in six cases.

A morphological, histological, and ultrastructural investigation was carried out on a series of six cases of malignant histiocytosis observed between 1973 and 1977. All lymph nodes were obtained prior to treatment. The histological findings revealed that the proliferating cell type was in all cases represented by histiocytes of varying degrees of atypia and with consistent phagocytic activity. In four cases, the histiocytic cellular proliferation also showed some degree of cohesiveness and, in two cases, there was capsular invasion. In three cases blood vessel invasion by malignant cells could be seen within the lymph node and in the surrounding tissue. On electron microscopy the tumour cells of malignant histiocytosis appeared to be pleomorphic with three types of cells: undifferentiated cells, histiocytes with variable degrees of differentiation, and cells with intermediate features. In particular, nonphagocytic and actively phagocytic histiocytes could be identified. The histological and ultrastructural data further support the idea that malignant histiocytosis is a disease that is related to the neoplastic proliferation of moderately differentiated histiocytes and their precursors. The latter may undergo various transformations with either apparently benign or definitely atypical morphological features.

Adolescent↗
PubMed1976

Relationship between nucleolar microspherule formation by urethan and inhibition of RNA and protein synthesis.

Liver tissues of suckling C3Hf mice treated with urethan, a carcinogen and inhibitor of RNA synthesis, and with cycloheximide, an inhibitor of protein synthesis, were studied by electron microscopy and by light microscope radioautography. At 4 and 12 hr after treatment with a single dose of urethan (1 mg/g body weight). [3H]uridine incorporation in hepatocyte nuclei was 38 and 9% lower than in controls and became 32% higher at 24 hr. Nucleolar microspherules were found 1.5 and 4 hr after the treatment, increased considerably in number at 10 and 12 hr, and decreased at 24 hr. These results suggest an inverse relationship between RNA synthesis and formation of microspherules. Cycloheximide alone (3 mg/kg body weight) produced microspherules, whereas in combination with a dose of 1 or 2 mg of urethan per g body weight it partially prevented or potentiated, respectively, the microspherule production.

Animals↗