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Biomedical subjects

V Marinozzi

Publications and source records attributed to V Marinozzi.

At least 37 records · Page 2Linked to original sources
PubMed1986

An improved periodic acid-thiosemicarbazide-osmium technique to reveal glycoconjugates at the molecular level in situ.

The periodic acid-thiocarbohydrazide or thiosemicarbazide-OsO4 method (Seligman AM, Hanker JS, Wasserkrug H, Katzoff L: J Histochem Cytochem 13:629, 1965) has been modified in order to obtain a periodic acid-Schiff (PAS)-like reaction for electron microscopy capable of visualizing structures at the molecular level in situ. Thiocarbohydrazide (TCH) and thiosemicarbazide (TSC) have been used dissolved in distilled water and bubbled with SO2. Treatment of previously oxidized thin sections with TCH (SO2) or TSC (SO2), followed by osmification, resulted in selective and very good staining of all the PAS-positive structures examined: glycogen, intestinal mucopolysaccharides, plasma membrane glycoproteins, basement membranes, Golgi apparatus, and collagen. The staining reaction was highly specific when TSC was used on thin sections from paraformaldehyde-fixed samples. The non-particulate end-reaction product made possible visualization of a periodic distribution of sugar residues in the 64-nm unit of collagen and the structural organization of the PAS-positive glycoconjugate components in the glomerular basement membrane.

Animals↗
PubMed1985

Visualization of the secretory canaliculi of human parietal cells with a peroxidase-labelled peanut lectin. Light- and electron-microscopic observations.

Peanut lectin reactivity was examined in normal fundic glands from human gastric samples, both at light- and electron-microscopic levels, using a peroxidase conjugate. Positive reaction was observed in the glycocalyx of parietal cell secretory canaliculi as well as in the mucous globules of mucous cells and in the luminal cell coat of chief cells. The presence of terminal galactose in the canalicular glycocalyx may be connected with the peculiar function of hydrochloric acid secretion. Peroxidase-labelled peanut lectin is proposed as a marker for visualizing the secretory canaliculus of parietal cells.

Galactose↗
PubMed1980

Multiple myeloma and acute myelomonocytic leukemia: simultaneous occurrence without previous chemotherapy.

A patient with acute myelomonocytic leukemia was found to have IgG paraprotein on serum electrophoresis Bence Jones K proteinuria and increased plasma cells (30%) on marrow examination. The simultaneous occurrence of the two diseases was well documented by cytochemical immunological and electron-microscopic findings. Bone marrow chromosome investigations showed an abnormal karyotype: hypodiploidy was prevalent and marker chromosomes were present. A possible relationship between acute leukemia and multiple myeloma is discussed.

Aged↗
PubMed1978

Antibody formation and transient immune complex glomerulopathy in A-strain mice with C1300 neuroblastoma tumors.

One to three-month-old A-strain mice, inoculated subcutaneously with 2 x 10(6) viable syngeneic C1300 neuroblastoma cells (clone NB9R) developed a palpable tumor within 9-12 days and died within 28-30 days. A transient glomerulopathy developed after 16-24 days. Despite a normal histologic appearance, the nephropathy was clearly demonstrated by electron microscopy and was classified as a focal mesangiopathic glomerulonephritis. Deposits of host 7S-G immunoglobulins and C3 complement fragments were detected in these same kidneys by immunofluorescence. Radioimmunoprecipitin determinations on sera obtained from mice at different intervals from tumor cell inoculation, revealed that untreated mice contained circulating antibodies capable of reacting with 125I-labeled gp69-71 glycoprotein from Gross murine leukemia virus (MuLV). Antibodies to p30 MuLV antigen and to crude membrane antigen (s) (CMA) solubilized from NB9R cells were found in sera only after tumor cell inoculation. Circulating immune complexes formed by host 7S-G immunoglobulins were clearly detected from day 16 to 22. Antibodies eluted from kidneys with nephropathy were shown to react with NB9R cells in vitro and to react specifically with CMA and the p30 MuLV antigen.

Animals↗
PubMed1977

Critical analysis of the use of the acrolein-Schiff method as a possible DNA reaction.

Histophotometric examination was carried out on nuclei of lymphocytes in human peripheral blood, which were subjected to various tests in order to assess the acrolein-Schiff method as a possible DNA specific reaction, in comparison with the traditional Feulgen reaction. Special attention was paid to the degree of difference between responses attributable to a direct Schiff reaction obtained in the fraction of nuclear proteins after treatment with acrolein. From the results obtained it appears that an acrolein-Schiff reaction, following extraction of proteins, may be considered a qualitative reaction for DNA. Our findings also show that there is no relationship between the degree of response to the acrolein-Schiff reaction and that the Feulgen reaction, which is to be expected in view of the different mechanisms of the two reactions.

Acrolein↗
PubMed1977

Mitochondrial inclusions in human cancer of the gastrointestinal tract.

Four cases of adenocarcinoma of the gastrointestinal tract have been examined. Large electron-dense mitochondrial inclusions were found in the mitochondria of many cells; after detailed histochemical tests they could be classified into two types. The first type of inclusion consisted of clusters of electron-dense, calcium-containing granules linked to a glycoproteic substrate. These inclusions were linked to a glycoproteic substrate. These inclusions were always associated with cristae and were found in the mitochondria of cells that showed clear signs of degeneration. The second type of inclusion was found much more frequently and consisted essentially of phospholipids of which electron density was strictly osmium dependent. Their structure was usually at least partly lamellar, but in some cases it was homogeneous throughout. It is hypothesized that inclusions of the second type may have the same biological role as the morphologically identical inclusions found in the mitochondria of brown fatty tissue in the perinatal rat and in yeasts during glucose repression or anaerobiosis. The resemblance between the homogeneous variety of inclusions within the second type and the mitochondrial inclusions recently described in human leukemic lymphoblasts and monoblasts has been stressed to bring out the need for a histochemical check on the supposedly viral nature of the latter inclusions.

Adenocarcinoma↗
PubMed1976

Effects of alpha-amanitine on chromatin in regenerating rat hepatocytes: a biochemical and morphologic study.

Almost all the chromatin in nuclei of regenerating rat liver hepatocytes 15 h and particularly 24 h after partial hepatectomy appeared as decondensed chromatin. Treatment with alpha-amanitine induced a clear condensation of decondensed chromatin as early as 30 min after toxin injection. The degree of condensation increased further until, 2 h after poisoning, almost all the chromatin was found to be in condensed form. Because the synthesis of DNA, after toxin injection, was not modified during the first 2h and 30 min, our results indicate that the chromatin condensation did not affect the synthesis of DNA. In the present paper the relationships between the inhibition of RNA synthesis and the chromatin ultrastructural changes are also discussed.

Amanitins↗
PubMed1976

Congenital extracardial malformations accompanying congenital heart disease.

A statistical review of 1,354 autopsies performed in cases of congenital heart disease in three major Italian hospitals was carried out. In 446 cases one or more extracardial malformations were found; those most commonly encountered were malformations of the urinary tract, anomalies of the respiratory tract, malformations of the intestine and spleen and trisomy 21. Ventricular septal defects and persistent common atrioventricular canals occurred in a higher percentage of cases with extracardial malformations than in those where congenital heart defects were the only malformations. The reverse was true of endocardial fibroelastosis and transposition of the great vessels. Ventricular septal defects are particularly common in the Klippel-Feil syndrome, in trisomy 18 and, together with a persistent common atrioventricular canal and atrial septal defects, in trisomy 21. The typical picture of so-called "congenital heart disease associated with asplenia" was found in cases with splenic agenesis, either with or without situs inversus viscerum, but also in cases with situs inversus viscerum without asplenia.

Abnormalities, Multiple↗
PubMed1973

The organic-inorganic relationship in calcified mitochondria.

Experimentally induced calcification within mitochondria has been studied electron rnicroscopically. Cells investigated comprise hepatic cells damaged by CCl(4) intoxication, myocardial cells damaged by prolonged dihydrotachysterol (DHT) administration, and cells from skeletal muscle (gastrocnemius) damaged by DHT sensibilization and local injury. Cells from a human bowel carcinoma were studied too. Two types of intramitochondrial inorganic inclusion have been found. The first consists of clusters of apatite-like, needle-shaped crystals (crystalline aggregates), the second of clusters of very fine granules (granular aggregates). The former have been found mainly in mitochondria in apparently normal myocardial and muscular cells, the latter in mitochondria of degenerated hepatic, neoplastic, and myocardial cells. Crystalline aggregates are closely related to the membranes of cristae at first, but they later spread to occupy the whole mitochondrial matrix. Granular aggregates are initially found in the mitochondrial matrix near, but perhaps not touching, cristae; by growing they come into close contact with cristal membranes. Both types of aggregate show intrinsic electron opacity, which disappears after formic acid decalcification. Only the crystalline aggregates give an electron diffraction pattern of crystallinity. Uranium and lead staining of decalcified sections shows that both types of aggregate are intimately connected with an organic substrate. The substrate of crystalline aggregates consists of very thin, elongated structures shaped like the inorganic crystals. The substrate of granular aggregates consists of amorphous material gathered in clusters, with the same roundish shape and intercristal position as the inorganic granules. Both types of substrate are stained by phosphotungstic acid at low pH and by silver nitrate-methenamine after periodic acid oxidation. These results show that the organic content of the substrates includes glycoproteins; they have been confirmed by the periodic acid-Schiff (PAS) method under the optical microscope. These findings have been discussed in relation to the recent discovery of organic Ca(2+)-binding sites in mitochondria and to the general problems of soft tissue calcification.

Animals↗