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Biomedical subjects

M De Luca

Publications and source records attributed to M De Luca.

At least 145 records · Page 8Linked to original sources
PubMed1989

Multicentre experience in the treatment of burns with autologous and allogenic cultured epithelium, fresh or preserved in a frozen state.

This report describes the clinical results obtained from a multicentre experience of the use of autologous and allogenic cultured human epidermal cells in the treatment of partial and full skin thickness burns. A laboratory has been organized to supply cultured epithelium to Burns Units in different cities. From May 1986 to December 1988, 58 patients with an age range of 1 to 59 years, and with burns covering between 7 and 95 per cent of the body surface area, have been treated. Graftable cultured epithelium can be frozen and remain viable if stored in a skin bank. Such grafts were used successfully to treat patients with partial and full skin thickness wounds.

Adolescent↗
PubMed1988

Human epithelial cells induce human melanocyte growth in vitro but only skin keratinocytes regulate its proper differentiation in the absence of dermis.

Human keratinocytes isolated from a skin biopsy and cultured in vitro reconstitute a stratified squamous epithelium suitable for grafting on burned patients. Melanocytes coisolated from the same skin biopsy also proliferate under these culture conditions and maintain differentiated functions (i.e., synthesize melanin granules, regularly intersperse in the basal layer of the cultured epidermis, and transfer melanosomes in the cytoplasm of contiguous keratinocytes) (De Luca, M., A. T. Franzi, F. D'Anna, A. Zicca, E. Albanese, S. Bondanza, and R. Cancedda. 1988. Eur. J. Cell Biol. 46:176-180). Isolated melanocytes in culture grow in the presence of specific growth factors with a mean population doubling time of 4-10 d. In this paper we show that (a) human keratinocytes and oral epithelial cells possess strong and specific melanocyte growth stimulating activity (doubling time, 24 h); (b) melanocyte growth is not autonomous but requires close keratinocyte contact and is regulated to maintain a physiological melanocytes/keratinocytes ratiol and (c) pure skin keratinocytes, but not oral epithelial cells, have all the information required for the proper physiological location and differentiation of melanocytes in the epidermis.

Cell Communication↗
PubMed1988

Coculture of human keratinocytes and melanocytes: differentiated melanocytes are physiologically organized in the basal layer of the cultured epithelium.

Human epidermal keratinocytes differentiate in vitro into a stratified epithelium suitable for grafting on burned patients. In this paper, we show that differentiated melanocytes are present in the cultured epithelium. In particular, we have found that i) melanocytes proliferate in the same culture conditions that allow keratinocyte growth, ii) during the culture the ratio between keratinocytes and melanocytes tends to remain constant, iii) melanocytes organize into the basal layer of the cultured epithelium independently of the presence of dermis, develop dendritic arborizations with melanosome-containing processes and transfer melanosomes into keratinocyte cytoplasm.

Cell Differentiation↗
PubMed1988

Antibiotic susceptibility of bacteria isolated from active, therapy-resistant periodontal sites.

Periodontally affected sites may show resistance to mechanical therapy associated with conventional treatment. This periodontal situation is the result of the cooperation of bacteria, and in some cases the development of superinfections due to opportunistic bacteria is possible. These situations need particular attention in the choice of antibiotics. From some sites, bacteria not commonly found as periodontal pathogens may be isolated; they are generally resistant to antibiotics administered in periodontal therapy. Attention should be used particularly in cases where lesions most resemble those characteristic of the action of gram-negative bacteria. According to results of the present research these cases should be managed with antibiotic combinations and conventional mechanical therapy.

Adolescent↗
PubMed1988

Clinical and microbiological effects of in vivo miocamycin therapy on oral infections and in surgical prophylaxis.

Periodontal disease is a chronic irregularly progressing condition, posing many therapeutic problems. Difficulties arise particularly when antibiotic therapy is to be added to mechanical and surgical therapy because, in these cases, pharmacotherapy must be long-lasting. For such reasons the antibiotic of choice must have high activity but low toxicity, in order to avoid side-effects. Antibiotic therapy is also used in both marginal and apical acute phlogistic cases, so that the ideal compound should have high diffusion in gingival tissues and alveolar bone. Miocamycin shows all of these features and it can thus be considered the antibiotic of choice in the therapy of acute periodontal infections and in stomatological surgery. In this clinical study the efficacy of miocamycin has been evaluated in 120 cases of acute periodontal phlogosis and in the treatment of advanced periodontal diseases. Patients were microbiologically monitored for the identification of aerobic and anaerobic bacteria all through the study. In acute cases very good results were obtained, both concerning the reduction of pathological signs (94.1% of the cases) and the occurrence of side-effects (10% of the cases). Among the patients who underwent surgical therapy, only 11 out of 80 showed small problems (slight fever and swelling).

Bacteria, Aerobic↗
PubMed1987

Characterization of phosphate residues on thyroglobulin.

Follicular 19 S thyroglobulin (molecular weight 660,000) from rat, human, and bovine thyroid tissues contains approximately 10-12 mol of phosphate/mol of protein. These phosphate residues can be radiolabeled when rat thyroid hemilobes, FRTL-5 rat thyroid cells, or bovine thyroid slices are incubated in vitro with [32P]phosphate. Thus labeled, the [32P]phosphate residues comigrate with unlabeled 19 S follicular thyroglobulin on sucrose gradients and gel filtration columns; are specifically immunoprecipitated by an antibody preparation to rat or bovine thyroglobulin as appropriate; and co-migrate with authentic 19 S thyroglobulin when subjected to analytic or preparative gel electrophoresis. Tunicamycin prevents approximately 50% of the phosphate from being incorporated into FRTL-5 cell thyroglobulin. Approximately one-half of the phosphate in FRTL-5 cell or bovine thyroglobulin can also be released by enzymatic deglycosylation and can be located in Pronase-digested peptides which contain mannose, are endo-beta-N-acetylglucosaminidase H but not neuraminidase-sensitive, and release a dually labeled oligosaccharide containing mannose and phosphate after endo-beta-N-acetylglucosaminidase H digestion. The remainder of the phosphate is in alkali-sensitive phosphoserine residues (3-4/mol of protein) and phosphotyrosine residues (approximately 2/mol of protein). This is evidenced by electrophoresis of acid hydrolysates of 32P-labeled thyroglobulin and by reactivity with antibodies directed against phosphotyrosine residues. The phosphoserine and phosphotyrosine residues do not appear to be randomly located through the thyroglobulin molecule since approximately 75-85% of the phosphotyrosine and phosphoserine residues were recovered in a approximately 15-kDa tryptic peptide or a approximately 24-kDa cyanogen bromide peptide, each almost devoid of carbohydrate. 31P nuclear magnetic resonance studies of bovine thyroglobulin confirm the presence and heterogeneity of the phosphate residues on thyroglobulin preparations.

Animals↗