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Biomedical subjects

C Ricci

Publications and source records attributed to C Ricci.

At least 361 records · Page 20Linked to original sources
PubMedDate not supplied

Accuracy of in-vivo assessment of prostatic volume by MRI and transrectal ultrasonography.

More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume.

Adenocarcinoma↗
PubMedDate not supplied

Density increase and ageing of erythrocytes in stored blood.

An increase in the density of erythrocytes was observed after storage of whole blood for 30 days at 4 degrees C in either acid citrate-dextrose or citrate-phosphate-dextrose-adrenaline. Glucose-6-phosphate dehydrogenase activity in unfractionated red blood cell lysates did not vary with the storage time. Enzyme activity in the lighter fraction separated by density gradient centrifugation was higher than that in heavier fractions. The decline in glucose-6-phosphate dehydrogenase activity with density was less marked after storage of whole blood for 30 days. It is suggested that density modifications are not related to the ageing of erythrocytes and additional mechanisms may be involved.

Blood Specimen Collection↗
PubMedDate not supplied

[Dynamics of the cell membranes].

The Author, after recalling the fundamental concepts of the function and structure of living cells, illustrate the functions characteristic of cellular membranes. He examines in detail the principal models which have been proposed for the interpretation of the structure of membranes, particularly those of DANIELLI and DAVSON and of ROBERTSON. He recalls his own biochemical experiments on the endoplasmic reticulum of the liver and spleen, from which useful information can be drawn on the locating of some catalytic proteins in the membrane. He then devoted particular attention to the relationships between proteins, lipids and glucides as constitutent parts of membranes and discusses the recent "fluid mosaic model" proposed by SINGER and NICOLSON. He concludes giving some examples of the functional flexibility of membranes and remarks that the collaboration between biochemists and electron microscopists has proved in the last few years to be a fertile point of encounter, promising results which will provide spectacular information on the structure and function of cellular membranes.

Animals↗
PubMedDate not supplied

[Single lung transplantation: experimental technique and functional results].

Single lung transplantation was performed in 22 pigs. The first 10 experiments were devoted to settle the surgical technique: in these cases we employed small animals (8-12 kg); technical difficulties and the high incidence of perioperative complications induced us to utilize bigger animals (greater than 20 kg) in the subsequent experiments. In the recipient, after left pneumonectomy we prepared the right pulmonary artery and encircled it with an inflatable silicon cuff connected to a reservoir positioned outside the chest cavity of the animal. The inflation of the cuff allows the complete occlusion of the right pulmonary artery and thus the functional evaluation of the isolated transplanted lung. Perioperative functional evaluation has been performed at different times till the third postoperative day, documenting the good status of the transplanted lung. This study confirms the possibility to employ pigs for experimental single lung transplantation to settle the surgical technique with economic and organizing advantages. Furthermore, it confirms the good results achieved in the dog, in which the occlusion of the contralateral pulmonary artery by means of an inflatable silicon cuff allows to evaluate the isolated transplanted lung function.

Anesthesia↗
PubMedDate not supplied

[Clinical magnetic resonance spectroscopy. The state of the art].

Magnetic resonance spectroscopy is a noninvasive technique which allows the study of the chemical composition of tissue. In the first part of this paper the authors describe the physical principles and the technical features of spectroscopy, including spectral acquisition, localization techniques and peak quantification. The second part of the paper regards the evaluation of the biological significance of the peaks observed in the most frequently studied spectra (31P and 1H). The third part concerns the clinical feasibility of magnetic resonance spectroscopy: in order to employ spectroscopy in the clinical practice, this technique should be able to fulfill such requirements as tissue characterization, metabolic quantification, therapy follow-up, biochemical understanding of the physiopathologic phenomena and pH evaluation. The fourth and last part of this paper deals with the clinical applications of spectroscopy. The authors consider the results of other research groups in the spectroscopic evaluation of the striate muscle, the central nervous system, heart, liver and some other organs. Then they describe some preliminary personal results in cerebral spectroscopy (41 healthy subjects studied with 31P and 5 with 1H) and liver spectroscopy (19 healthy subjects studied with 31P and 9 healthy subjects and 9 patients with liver steatosis studied with 1H). The authors conclude that the problem of the potential clinical application of spectroscopy is still open. So far the use of this technique is limited to research centers, which should point out the clinical role of spectroscopy.

Humans↗
PubMedDate not supplied

[Mini-laparoscopic cholecystectomy: indications, technique and results].

The improvement of results and patients quality life is the aim of surgical technique. Mini-laparoscopic cholecystectomy brings not only to a better cosmetic results, but also to a decrease of post operative pain, analgesic use, hospital stay and an early return to normal activities. In this study, Authors report their own experience about mini-laparoscopic cholecystectomy using 5 mm and 3 mm trocar. Patients suffering from biliary sludge, microscopic lithiasis and mild or moderate gallbladder inflammation can undergo this procedure.

Cholecystectomy, Laparoscopic↗
PubMedDate not supplied

[Physiopathology and clinical aspects of monoclonal IgM gammopathy].

Ten subjects with IgM monoclonal gammopathy were studied with particular references to their clinical pictures. In 7 cases, the M component was W's macroglobulinaemia (MW) and in 3 undetermined monoclonal gammopathy (UMG). Serum IgM was always greater than 2170 mg% in MW and greater than 1120 mg% in UMG. All patients were over 45. Haemorrhage and autoimmune phenomena were noted in 2/10 cases, and liver and spleen enlargement in 7/10, peripheral lymphocytosis in 5/10, marrow lymphoplasmacytosis in 7/10, and plasma hyperviscosity in 7/10. Beta-2-microglobulin (beta-2MG) was higher on average in the 7MW cases than in the 3 UMG. A monoclonal peak was observed casually in 2/10 and after it had been clinically suspected in 3/10. ESR was high in all cases. The clinical and laboratory data are interpreted in the light of the possible pathogenetic mechanism. In addition, stress is laid on their importance in the differentiation of these two forms of IgM monoclonal gammopathy.

Aged↗
PubMedDate not supplied

Superior pulmonary sulcus tumors: radical resection and palliative treatment.

Between 1963 and 1987, 56 patients with Superior Pulmonary Sulcus Tumors (SPST) were seen at our Institution. Fifteen inoperable patients were treated by radiotherapy. Forty-one patients underwent surgery: 32 received preoperative irradiation and in four of these postoperative radiotherapy was also administered: in nine cases (non radical resection) radiotherapy was administered postoperatively only. Paulson's approach was employed in 30 cases and Dartevelle's procedure in 11. The resection was considered curative in 22 patients (53.7%) achieving complete palliation of pain in 68.2% of cases. In non-resectable patients 2-year survival was 6%. Five-year survival was 11.1% for patients with non radical resection and postoperative irradiation and 34% for patients undergoing preoperative irradiation and radical resection. Four patients underwent pre- and postoperative irradiation and they are alive 23, 20, 15 and six months after operation. Five-year survival for N0, N1 and N2 patients was 38.1%, 14.3% and 0% respectively. In conclusion, SPST can be radically resected, with the appropriate surgical approach and after preoperative radiotherapy, achieving good long-term survival and pain relief. Postoperative irradiation is advisable for prevention of local recurrence and longer pain relief.

Abdominal Muscles↗
PubMedDate not supplied

Kinetic properties and physiological regulation of NAD glycohydrolase.

Kinetic studies on horse spleen NAD-glycohydrolase demonstrate that the hydrolysis of NAD+ is extensively inhibited by physiological concentrations of nicotinamide and NADP+. These compounds act as reversibly released product and competitive inhibitor respectively.

Animals↗
PubMedDate not supplied

[Echography and computerized tomography in the diagnosis of complex abdominal lesions].

Complex abdominal lesions include a variety of pathologies, such as septated, infected, and hemorrhagic cysts, abscesses, tumors, and fluid collections of different etiology. These lesions present diagnostic difficulties with both Ultrasonography (US) and Computed Tomography (CT), since findings may not be present or, when present, are not specific. Keeping these limitations in mind, we evaluated 105 patients (111 abdominal lesions) with both US and CT in order to compare their adequacy in predicting the nature of the lesion. On the basis of US and CT results, complex abdominal lesions were divided in four classes: class I includes 43 cases in which both examinations gave the same contribution to the definition of the nature of the lesion, class II (14 lesions, mainly sepimentated cysts), in which US was superior to CT, class III includes 45 cases in which CT was superior to US, mainly in case of hemorrhagic cysts, abscesses, fluid collections and, less frequently, cystic tumors; class IV includes 9 cases in which US and CT results were complementary, which allowed the nature of the lesion to be defined. In conclusion, US and CT enable the identification and the characterization of complex abdominal lesions; an association of the two investigations enhances their diagnostic value. As a rule, CT is superior when the content of the lesion is either gas or hemorrhage, and in the definition of its peripheral wall. US is always superior in assessing septa, and sometimes even vegetations.

Abdomen↗
PubMedDate not supplied

Interrelationship between adenine and pyridine nucleotide metabolism in human erythrocyte life span.

Adenyl and pyridine nucleotide production has been tested in the whole erythrocyte population and in cells of different age, separated by Percoll density gradient. Both the cellular nucleotide production from adenine and nicotinic acid and the related phosphoribosyltransferase activities show a decrease during cellular life span. Pyridine nucleotide production decay in intact cells parallels the NAPRT pattern, while APRT decrease during senescence is greater than cellular adenine nucleotide production decay.

Adenine Nucleotides↗