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Biomedical subjects

S Riccardi

Publications and source records attributed to S Riccardi.

At least 19 recordsLinked to original sources
PubMed2004

[Anaesthesiologic problems about hyperthermic intraoperative intraperitoneal chemotherapy].

The literature considers hyperthermic intraoperative intraperitoneal chemotherapy a safe and effective procedure for peritoneal carcinomatosis, but a technical improvement is necessary. Regional chemotherapy anticipates the "downfall" of tumoral cells in the peritoneum. The Authors considered 5 patients--female, age 27-45 years, ASA 2--operated of peritonectomy in ovaric neoplasia with peritoneal metastasis. The hyperthermic intraoperative intraperitoneal chemotherapy has been made at the end of the surgery with a hot solution (43 degrees C): 3000 ml of dextrose 1.5% with mytomicina C 25 mg e cysplatino 75 mg/m2. We considered variation of emodinamic parametres (blood pressure, central venous pressure, stroke volume, etc.) and biochemical parametres (Na, K, CI-, CO2, etc.). These parametres have been correlated with some complications: fistula, anastomotic leakage, pancreatitis and postoperative bleeding.

Adult↗
PubMed1998

Sulfide enhancement of PMN apoptosis.

Hydrogen sulfide is a toxic metabolite released by several bacterial agents under anaerobic conditions. In the present paper, we investigated the effects of sulfide on polymorphonuclear cell (PMN) apoptosis, a mechanism suggested for limiting the toxic potential of neutrophils in inflammatory sites. We showed that 1 mM sulfide (concentration not conditioning PMN viability) is able to enhance the apoptotic fate of human granulocytes by increasing: i) the number of cells containing pyknotic nuclei, ii) the internucleosomal cleavage, and, iii) the intensity of tubulin immunofluorescence staining. The sulfide effect is partially prevented by ionomycin and this finding is consistent with the hypothesis of the inhibiting role played by high levels of cytosolic calcium in PMN apoptosis modulating.

Apoptosis↗
PubMed1991

Inhibitory effect of retinoids on the generation of procoagulant activity by blood mononuclear phagocytes.

Retinoids are known to modulate several functions of mononuclear phagocytes. We have studied the effect of retinyl acetate (RAc) and retinoic acid (RA) on the production of procoagulant activity (PCA) by human peripheral blood mononuclear cells stimulated with endotoxin (1 microgram/ml, 4 or 20 h at 37 degrees C). Both compounds caused a dose-dependent reduction in the expression of cell-associated PCA (from 86 to less than 10% of control in the range of concentration comprised between 0.1 and 100 microM). This effect was also observed when the cells were exposed to retinoids for 10 min and washed before challenge with endotoxin, indicating that it is rapid and irreversible. In contrast, incubation of RAc or RA for 3 h at 37 degrees C with cells that have been already stimulated with endotoxin (20 h at 37 degrees C) remained without influence on cell PCA. The inhibitory action of retinoids was also observed when monocyte-enriched (greater than 85%) preparations or highly purified monocyte-derived macrophages (greater than 99%) were used instead of whole mononuclear cells. BW755C, an inhibitor of cyclo-oxygenase and lipoxygenase, reversed the inhibitory effect of retinoids, whereas acetylsalycilic acid, an inhibitor of cyclo-oxygenase, was inactive, suggesting the involvement of a lipoxygenase product. The inhibition of monocyte/macrophage PCA production and the subsequent reduction of cell potential for fibrin deposition might represent one of the mechanisms whereby retinoids exert their antiinflammatory and immunomodulatory activities.

Blood Coagulation↗
PubMed1991

Retinoids inhibit the respiratory burst and degranulation of stimulated human polymorphonuclear leukocytes.

Retinoids exhibit a wide spectrum of activities, including antiinflammatory properties. We have investigated the effect of retinoic acid (RA) and retinyl acetate (RAc) on the production of reactive oxygen metabolites and the release of lysosomal enzymes by human polymorphonuclear leukocytes (PMN). Incubation of PMN with RAc or RA (1-100 microM) caused a dose-dependent inhibition (upto 90%) in O2- production and chemiluminescence induced by phorbol myristate acetate (PMA), N-formyl-methionyl-leucyl-phenylanaline (fMLP), opsonized zymosan or ionophore A23187. Both retinoids (1-100 microM) also inhibited, in a dose-dependent way, degranulation induced by fMLP (upto 85% at the highest concentration of RA). These inhibitory effects appear irreversible, since they persist after the drugs are removed and the cells washed before stimulation. Inhibitors of cyclo-oxygenase activity such as acetylsalicyclic acid and indomethacin did not influence the effects of RAc. In contrast, BW755, an inhibitor of both cyclooxygenase and lipoxygenase, reversed the inhibitory action of RAc, suggesting that the effect of retinoids occurs possibly through the mediation of lipoxygenase products. The modulation of PMN oxidative metabolism and degranulation might help explain the antiinflammatory properties of retinoids.

Calcimycin↗
PubMed1988

Cefoperazone plus mezlocillin for empiric therapy of febrile cancer patients.

Two dosing regimens of cefoperazone plus mezlocillin were compared in a prospective, randomized trial for therapy of febrile cancer patients. The two regimens were 5 g mezlocillin plus 2 g cefoperazone intravenously every four hours (higher dose) or 3 g mezlocillin plus 1 g cefoperazone intravenously every four hours (lower dose). Although the overall response rate was higher with the higher dose regimen (78 percent versus 66 percent, p = 0.04), the two regimens were comparable in patients with documented infections (72 percent versus 68 percent). Likewise, the two regimens were equally effective against those infections in which the pathogen could be determined (82 percent versus 82 percent). Serum bactericidal titers of at least 1:32 against a known pathogen were associated with a higher response rate than were titers of less than 1:32, but the higher dose regimen did not result in higher serum bactericidal titers. Hypoprothrombinemia was a side effect, especially with the higher dose regimen, before prophylactic vitamin K was routinely administered to patients. Since there were no major benefits with the use of the higher dose regimen of mezlocillin plus cefoperazone, the lower dose regimen is more appropriate for routine usage.

Adolescent↗
PubMed1986

Cytochrome b and FAD content in polymorphonuclear leucocytes in a family with X-linked chronic granulomatous disease.

Chronic granulomatous disease (CGD), an immunodeficiency syndrome characterized by extreme susceptibility to bacterial infections, is due to a defect of the respiratory burst in human phagocytes. NADPH oxidase, the enzyme that catalyzes the reduction of oxygen and the release of oxidative radicals, was studied in polymorphonuclear leucocytes (PMNs) in a family affected by an x-linked inheritance form at high penetrance of the disease. The contents of cytochrome b, suggested as the terminal component of the oxidase electron transport chain, and FAD, the hypothetical proximal component of the chain, were determined in patients and in carriers. Cytochrome b showed the typical behaviour of x-linked CGD: total absence in patients, intermediate values in carriers. FAD content evaluated on plasma membranes was less decreased than cytochrome b. Carriers also showed a decrease of this flavoprotein. Cytochrome b and FAD contents were compared to NBT test and superoxide production: a clear correlation was observed for the cytochrome b, but FAD plasma membrane evaluation could also be an interesting tool for the metabolic characterization of the disease in patients and in carriers.

Adult↗
PubMed1985

In vitro cisplatin effects on phagocyte functions.

The effects of cis-diamminedichloroplatinum (II) (cisplatin), a drug used in cancer chemotherapy, on the oxidative metabolism, endocytosis, chemotaxis and exocytosis of guinea-pig polymorphonuclear leukocytes were studied. All these functions were negatively influenced, but the same effect (50% inhibition) was observed at different drug concentrations (3 X 10(-5) M for chemotaxis, 10(-4) M for O2 consumption by FMLP and beta-glucuronidase release, 10(-3) M for O2 consumption by PMA and for zymosan engulfment). The effects of the drug can be explained by its ability to bind to membrane proteins, essentially to -SH groups.

Animals↗
PubMed1984

Effect of cisplatin on the oxidative metabolism of polymorphonuclear leukocytes in cancer patients.

Peripheral blood polymorphonuclear leukocytes of patients with ovarian or uterine-cervix carcinoma were studied during cisplatin chemotherapy for phagocytic oxidative metabolism. In particular, superoxide production by these leukocytes after stimulation with opsonized Zymosan particles was determined. The basal value of oxidative metabolism of leukocytes from neoplastic patients was lower than in normals. Superoxide production decreased after each dose administration, but returned to normal at the end of the entire chemotherapeutic treatment. It is suggested that cisplatin treatment, despite a short-lived depression of oxidative metabolism in polymorphonuclear cells, improves this function, most probably by interfering with neoplastic growth.

Cisplatin↗
PubMed1979

Biological activity of metal complexes. I. Interaction of pt(II), pd(II) and rh(I) complexes with E. coli strains and with mice LS fibroblasts in vitro.

The effects of a number of Pt(II, Pd(II) and Rh(I) complexes against cultures of Escherichia coli (strains B, H10178, uvra-, recA-) and cultures of mice LS Fibroblasts were tested. Most of the compounds showed higher cytotoxic activity than the cis-Pt(NH3)2Cl2, the compound at present on clinical trial as antittumour drug. A new model of active compound is proposed.

Anti-Bacterial Agents↗
PubMedDate not supplied

Modifications of macrophage chemotaxis in rats bearing the transplantable tumour reticulosarcoma 'IRE'.

Macrophage chemotactic activity was studied as a marker of the anti-inflammatory effect accompanying tumour growth. An inhibiting effect of the tumour on the macrophage mobility was observed by comparing the macrophages collected from normal rats and those from animals bearing the IRE reticulosarcoma. To explain these results, it is postulated that a MIF, or a similar inhibiting factor is released by the tumour. Both the the nature and function of such a factor(s) remain to be clarified.

Animals↗
PubMedDate not supplied

[Informed consent forms in medical practice: the results of a knowledge survey].

"Federico II" University of Naples Hospital Management's Staff considered 47 informed consent forms in order to evaluate quality and quantity of the information transmitted to patients. Every form, distinguished by procedure (surgical, pharmacological, anesthesiologic or related to blood transfusions) was evaluated for the accuracy and validity of information related to: diagnosis, prognosis, diagnostic and therapeutic opportunities, expected benefits, adverse-side effects, iatrogenic risks, privacy policy on personal data. The forms were judged by information completeness criteria "conformed" or "not conformed" with standards. Our analysis demonstrate that physicians often are unaware of legal and ethical topics related to constructing informed consent forms. They usually omit crucial information or would use strict technical language. So far, we conclude Hospital Management's Staff definitively has a role in improving informed consent forms by establishing guidelines and promoting ethical issues. Final result could be to deserve stronger patient confidence in medical institutions.

Adult↗
PubMedDate not supplied

[Appendiceal lithiasis: case report and review of literature].

Appendiceal calculi are found in a limited percentage of patients. They are in association to an elevated prevalence of necrotic appendicitis and perforation of the appendix. The Authors report a case of acute appendicitis associated to appendiceal lithiasis with perforation of the organ. They emphasize the possibility to perform a preventive appendectomy in case of incidental appendiceal lithiasis. Besides they consider the differential diagnosis of the calcified images located in the lower abdominal quadrants with the aid of the various imaging methods available today, particularity sonography and computerized tomography.

Adult↗
PubMedDate not supplied

[A case of total spinal block during epidural anaesthesia].

Most cases of total spinal block have been reported in the literature. The displacement of the catheter and the consequent dural perforation are the causes in large percentage of the patients (75%). The Authors describe this case for the importance of the causes and outcome of the patient. A 48 years old woman presented for hysterectomy for uterine fibromas. After having individualized the L3-L4 interspace, a test dose of 3 ml carbocaine 2% was injected. After that, the spinal block was obtained using ropivacaine 0.75% (total dose = 10 ml) injecting slowly, in following times, 5+5 ml of anaesthetic solution. The patient, perfectly conscious at first, presented a gradual increase of the difficulty in talking and breathing. Subsequently she showed a complete paralysis with loss of the consciousness, respiratory arrest, bilateral and symmetrical midriasis, as well as total areflexia. Endotracheal tube was placed. After eighty minutes from the end of the administration of the local anesthetic, spontaneous thoracic excursions appeared, even though of moderate ampleness, midriasis reduced. The patient recovered consciousness and sufficiently ventilated; therefore the endotracheal tube was removed.

Amides↗
PubMedDate not supplied

[Candida albicans infection: in vitro immunity aspects].

The authors have investigated the chemotactic ability of C. albicans toward macrophages and polymorphonuclears. Experiments, carried out by modified Boyden chamber, lead to isolate a chemotactic agent, considered either a moderate cytotaxin, or an excellent cytotaxigen.

Animals↗
PubMedDate not supplied

[Effects of cis-platin on the contractile system of polymorphonuclear leukocytes].

The effects of cis-Platinum, a new antitumor drug, on guinea pig polymorphonuclear functions related to subplasmalemmal fibrillar structures, were investigated. The compound markedly decreased chemotaxis. Zymosan particles engulfment and degranulation. The depression of these leucocyte activities adds to the already known drug induced myelotoxicity .

Animals↗