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Biomedical subjects

C Ricci

Publications and source records attributed to C Ricci.

At least 235 records · Page 13Linked to original sources

Purine and pyridine nucleotide production in human erythrocytes.

Human erythrocyte adenyl and pyridine nucleotide production has been tested in cell-free lysates and in intact cells. The main products obtained in cells incubated with adenine and nicotinic acid are adenosine triphosphate and nicotinate mononucleotide, respectively, under any experimental condition used (incubation time, base concentration). Adenine-phosphoribosyltransferase activity determined in crude lysates is about 100 times higher than nicotinate-phosphoribosyltransferase activity, while cellular adenyl nucleotide production is only three times higher than that of pyridine nucleotide. A strong intracellular regulation for the former, but not latter, synthetic process is thus suggested. Intact erythrocyte nicotinate nucleotide production is inhibited by adenine, while nicotinate-phosphoribosyltransferase activity is not. The possible regulation by adenyl nucleotides is discussed in light of the modulating action of ATP on nicotinate-phosphoribosyltransferase activity. The kinetic characteristics of both adenine- and nicotinate-phosphoribosyltransferases, determined on crude lysates, are reported.

Adenine Nucleotides↗

Immunological features of endemic goiter.

Some immune aspects of simple endemic goiter have been studied through a comparison of IgG, IgA, IgM, kappa and lambda chains, and C3 and C4 in the peripheral blood of 59 patients operated on for goiter and the peripheral blood of 49 normal controls. The median IgM was lower in the goiter blood. The incidence of thyroglobulin (Tg) and microsomal (Mi) antibodies (Abs) was 20.3% in goiter blood and that of nonthyroid autoAbs was 37%. Active and total rosetted blood lymphocytes were counted and OKT3, OKT4, OKT8, Leu 1, Leu3a, Leu2b, T DR+, and NK cell populations were classified. Helper T cells were occasionally decreased when goiter was associated with lymphocytic thyroiditis. The NK percentage was sometimes higher in goiter blood, whereas the T DR+ percentage was not significantly different in the two groups. Lymphocyte infiltration (LI) was noted in 32% of goiters (about 5% with a diffuse and nodular pattern). A prevalence of helper/inducer cells was observed among the infiltrating T cells. HLA-DR antigen (Ag) positive epithelial cells were seen, not only in LI areas. Granular deposits of IgG, IgA, IgM, and C3 on the follicular basal membrane were stained in 6.7% of goiters Patterns histologically and immunologically similar to those in Hashimoto's thyroiditis may therefore be observed in long-standing simple endemic goiter, suggesting that an autoimmune mechanism may be involved in its pathogenesis.

Autoantibodies↗

[Pyridine metabolism of the human erythrocyte].

Pyridine nucleotides are required for human erythrocyte survival, for their role in both glycolysis and pentose phosphate pathway. Human red blood cells have been used for the study of some pyridine nucleotide cycle reactions, but the whole sequence in the erythrocyte has not yet been completely determined. In the present work, pyridine coenzyme synthesis interrelationships and degradation have been revised, both in general and regarding to human erythrocytes. These cells are lacking the de novo pathway, and utilize exogenous free bases, especially nicotinic acid, as NAD precursors. Nicotinamide utilization is discussed in view of its role in the salvage pathway. Available data on enzyme kinetic and regulation characteristics are reviewed.

Adenosine Diphosphate↗

[Percutaneous drainage of abdominal abscesses].

Percutaneous puncture with echographic guide was performed in 37 patients with suspected abdominal abscesses. The abscess has been confirmed in 31 cases and it has been related to previous surgery in 21. In 3 cases the 3 small cavities were evacuated by a single-stage aspiration; in the other cases different drainage catheters, in relation to the size and the content of the cavities have been employed. Benefits of proteolytic agents, irrigation with saline solution and permanent aspiration are stressed. Successful drainage avoiding surgery was achieved in 23/31 patients (74%), and positive results have been obtained in multiple abscesses, multilocular abscesses and infected haematomas as well. A partial success was achieved in 3 cases (10%): the patients were submitted to surgery after a clinical improvement. Two complications occurred (bowel perforation and small liver laceration). The percutaneous drainage turned out to be a technique of choice in the great majority of abdominal abscesses, and should be considered a good alternative to surgery, particularly in high risk patients.

Abdomen↗

Pulmonary resection for metastatic laryngeal carcinoma.

In a 5 year period, 11 patients were referred to our department as candidates for resection of pulmonary metastases from laryngeal carcinoma. At thoracotomy, a second primary tumor of the lung was discovered in three patients (27%). The other eight were considered eligible for thoracotomy and were subsequently proved to have metastases. Two of these patients (Group I) refused surgical treatment and died after 10 and 12 months; histologic diagnosis was obtained at autopsy. Six patients (Group II) underwent curative resection: Two of them have died (26 and 34 months) and four are alive and free of disease 40, 43, 46, and 55 months after thoracotomy. The disease-free interval, stage of primary tumor at laryngectomy, and single versus multiple metastases do not seem to affect survival. We conclude that lung resection increases survival in patients with pulmonary metastases from laryngeal carcinoma.

Aged↗

Median sternotomy for resection of lung metastases.

Three patients operated upon via median sternotomy for resection of bilateral lung metastases are presented. 2 show no evidence of disease 30 and 42 months after operation, one died 10 months after surgery. The literature on the subject is reviewed; median sternotomy is considered a quick, safe and reliable route, indicated when resection of bilateral lung metastases is to be carried out.

Adult↗

[Clinical control of the quality of dynamic echography].

The performances of 4 real-time scanners (2 mechanical sector scanners and 2 linear electronic scanners) have been tested. The clinical test used was the examination of liver, gallbladder and biliary tract and in other circumstances the examination of kidney and breast. The quality of the scanners has been judged on the ground of four parameters: the diagnostic quality of the image (DQI) the overall quality of the image (OQI), the efficiency of the exploration (EE) and feasibility of use (FU). The ideal conditions of use for each technology are described and the authors emphasize the impact of improved technology on the quality of the ultrasonographic scanners.

Gallbladder Diseases↗

Immunological studies on the origin of the precursor cells in Waldenström's macroglobulinemia.

Preliminary results obtained with OK anti-T and FMC anti-B monoclonal antibodies in a study of peripheral blood lymphocytes from eight patients with Waldenström's macroglobulinemia and of bone marrow lymphocytes from three patients, are reported. Endocytoplasmic immunofluorescence revealed a 1 to 3% marrow plasma cell fraction in all three cases, together with an approximately 10% increase in the monoclonal precursor compartment. Displacement of the peripheral blood helper: suppressor ratio was also observed using anti-T-lymphocyte monoclonal antibodies.

Humans↗