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C Palumbo

Publications and source records attributed to C Palumbo.

41 records · Page 3Linked to original sources
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Histomorphometric study on the osteocyte lacuno-canalicular network in animals of different species. II. Parallel-fibered and lamellar bones.

The shape, size and density of osteocyte lacunae in parallel-fibered and lamellar bone were histomorphometrically analyzed in relation to the organization of the collagen fiber texture and the animal species (frog, sheep, dog, bovine, horse and man). The following parameters were measured under the light microscope (LM) by a computer-assisted image analyzer: 1) shape, size and distribution of osteocyte lacunae; 2) osteocyte lacuno-canalicular density. In close agreement with our previous studies, which includes woven bone, it resulted that in all animals (even in frog) osteocyte lacunae have a rounded globous shape in woven bone and an oval shape in both parallel-fibered and lamellar bone; in the latter, however, they are more flattened, only located in loose lamellae and thus regularly distributed in rows. Osteocyte lacunar density is higher in woven-fibered, intermediate in parallel-fibered and lower in lamellar bone, whereas no correlation seems to exist with the animal species. In conclusion, these results suggest that osteocyte shape, size and density seem to depend mainly on collagen fiber texture rather than on the animal species. The role of osteocyte-recruitment on the spatial organization of collagen fibers in bone tissues is discussed.

Animals↗
PubMedDate not supplied

[Sensitivity to antibiotics of the "Neisseria meningitidis" strains isolated among healthy subjects (author's transl)].

In 1977, from March through April, 16 strains of N. meningitidis were isolated among 400 healthy subjects: 334 school-children 6-11 years of age and 66 adults, with a carrier rate of 3.85% and 4.5% respectively. The serological identification carried out by slide agglutination showed: 1 strain belonging to serogroup A; 4 strains to serogroup B; 1 strain to serogroup C; 1 strain to serogroup Y; 3 strains were autoagglutinable and 5 nonagglutinable. Minimum inhibiting concentrations of sulfamethoxypyrazine and some antibiotics (penicillin, streptomycin, rifampicin, chloramphenicol, chlortetracyclin) were determined for 12 strains. All the isolates were inhibited by a concentration of rifampicin of 0.2 microgram/ml, whereas 2 strains were resistant, respectively, to 0.8 UI/ml of penicillin (M.I.C. greater than 0.8 less than or equal to 1 UI/ml) and to 4 UI/ml (M.I.C. greater than 4 less than or equal to 6 UI/ml). Various levels of resistance to sulfamethoxypyrazine and other antibiotics were also noted.

Anti-Bacterial Agents↗
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[Effects of PDGF AB on extracellular matrix synthesis by human mammary fibroblasts].

PDGF AB effect on extracellular matrix protein synthesis and release by a primary culture of non transformed human mammary fibroblasts was analyzed. Primarily PDGF AB induced a modified protein distribution, with a global enhancement of secreted proteins as compared to intracytoplasmatic proteins. Furthermore, an increase in synthesis and release of the extracellular matrix proteins such as fibronectin and type I and IV collagens upon PDGF AB treatment with specific immunoprecipitation was demonstrated.

Aged↗
PubMedDate not supplied

Histomorphometric study on the osteocyte lacuno-canalicular network in animals of different species. I. Woven-fibered and parallel-fibered bones.

A comparative histomorphometric study was carried out on the extension of lacunocanalicular network in two types of bone tissue (woven and parallel-fibered) in shaft bones of various animals (Frog, Chicken, Rabbit, Bovine, Horse, Dog, Man), with the aim to understand whether the distribution of osteocyte network is related to the organization of the collagen fibers or to the animal species. By means of a light microscope (LM) connected with an image-Analyser the following parameters were measured: 1) the cross-sectional area and the volume of osteocyte lacunae; 2) the osteocyte density; 3) the number of canaliculi departing both from the whole outline of the sectional area of osteocyte lacunae and, in the parallel-fibered osteons only (both with LM and SEM), from their two opposite walls, i.e., from the wall facing the Haversian canal (vascular wall) and from that facing the cement line (peripheral wall). In all the animals studied the size and density of osteocyte lacunae as well as the extension of the canalicular network proved to be markedly higher in woven than in parallel-fibered bone, whereas no relation with the species was found. These findings suggest that the function of osteocyte is mainly involved in the regulation of skeletal homeostasis, as discussed in the present paper.

Animals↗