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Biomedical subjects

V De Angelis

Publications and source records attributed to V De Angelis.

At least 55 records · Page 3Linked to original sources

Time-related shape control modifications during erythrocyte storage with additive solutions.

To obtain more detailed information on the reversibility of shape alterations in blood bank stored erythrocytes, we have studied shape recovery after chemical crenation and rheological properties in 8 PAGGS-sorbitol preserved erythrocyte concentrates during a five week storage period under blood bank conditions. Our results show that red cell capability to regain a normal discoid shape after chemical crenation decreases during storage but is not lost over a five week period. Moreover there is a significant but weak correlation between red cell ATP content and both shape recovery capability and viscosity. Our results confirm suspicious that red cell shape perturbations following blood bank storage are widely reversible. Two different mechanisms may be involved in reducing shape recovery capability during storage, namely an ATP-dependent mechanism and an energy-independent one. The energy dependent mechanism may be preserved by the previous addition of solutions which maintain higher energy levels during storage.

Adenine↗

Modulation of NK activity by thymic hormones: in vitro effects of thymostimulin.

Plastic-adherent depleted or not depleted peripheral mononuclear blood cells (PMBC) from healthy donors showed enhanced lytic activity against 51Cr-labelled K562 target cells when exposed to thymostimulin (TS), 1 microgram ml-1, for 3 h, washed and incubated in TS-free medium before testing for natural killer (NK) cytotoxicity. No modification of NK cell activity was seen when effector cells were treated with placebo (splenic extract). The NK boosting activity of TS was lost when effector cells were treated for 3 h immediately before the performance of the cytotoxic test or when this thymic extract was added directly to the mixture of effector and target cells during the lytic phase of 51Cr release assay.

Cell Survival↗

A phase I study of human natural interferon-beta in cancer patients.

In this phase I study 15 patients with metastatic tumors were given interferon (IFN)-beta by i.v. bolus injections. Twelve individual doses of 1, 2, 3.3, 5, 7, 9, 12, 16, 21, 27, 35, and 46 x 10(6) IU were administered every other day. The single maximal tolerated dose ranged from 9 to 46 x 10(6) IU. Eight patients tolerated the dose of 46 x 10(6) IU without side effects. Disturbances of cardiac rhythm were observed, but were closely related temporally to severe chills and appeared to be the consequence of adrenergic stimulation associated with this side-effect. In addition, no significant variations in the left ventricular function as assessed by nuclear stethoscope were observed. Neurotoxicity was not a major side-effect. The toxicity of IFN-beta given as scheduled in this study was significant, but acceptable.

Adult↗

Platelet membrane abnormalities in myeloproliferative disorders: decrease in glycoproteins Ib and IIb/IIIa complex is associated with deficient receptor function.

The number and functional activity of membrane glycoproteins (GP) Ib and IIb/IIIa were investigated in platelets from 11 patients with myeloproliferative disorders (MPD). Three patients had essential thrombocythaemia, two had chronic myeloid leukaemia and six had polycythaemia vera. The numbers of GPIb and GPIIb/IIIa molecules were detected on the platelet surface using different 125I-labelled monoclonal antibodies. The functional properties of GPIb and GPIIb/IIIa were evaluated using purified 125I-labelled asialo von Willebrand factor (vWF) and purified 125I-labelled fibrinogen, respectively, in a binding assay. Binding of the anti-GPIIb/IIIa antibody was decreased by 40% in almost all patients studied and, when measured, it was accompanied by decreased fibrinogen binding to activated platelets. Binding of anti-GPIb antibodies to platelets was also slightly decreased or virtually the same in eight out of 11 patients. The decrease correlated with decreased binding of asialo vWF. The increased plasma glycocalicin levels, measured in four patients, depended on the high platelet count. Scatchard analysis revealed normal receptor binding affinity for all ligands tested in all but one patient. In this report we demonstrate that abnormalities in the concentrations of GPIIb/IIIa membrane proteins are commonly present in patients with MPD, while a decrease in GPIb concentration is also seen, although in fewer patients. These abnormalities are accompanied by a concurrent decrease in the respective receptor functions. These findings may explain part of the haemorrhagic tendency often encountered in MPD.

Antibodies, Monoclonal↗

Bronchial hyperresponsiveness in atopic dermatitis.

We investigated the prevalence of bronchial asthma, immediate skin reactivity and bronchial hyperresponsiveness in 40 patients with atopic dermatitis (AD). Eight patients reported to have asthma while 29 were found responders to methacholine test (PC20 Mch less than 64 mg/ml) and 21 were skin reactors. The prevalence of skin positive reactions did not differ in responder and non-responder (PC20 Mch greater than 64 mg/ml) groups. Males were more likely both to have bronchial asthma and be responders to methacholine test than females. Moreover, responders had an earlier age of onset of AD than the non-responders. We suggest that bronchial responsiveness should be evaluated in children with AD.

Adolescent↗

Rheological abnormalities of erythrocyte deformability and increased glycosylation of hemoglobin in the nephrotic syndrome.

This report is an attempt to gain more complete knowledge of the causes of the tendency to thrombosis in the nephrotic syndrome. Our purpose was to detect some rheological abnormalities in a group of nephrotic patients having normal renal function. Plasma and blood viscosity, erythrocyte filtration flow (EFF) and some indices of the carbohydrate metabolic state (glycosylated hemoglobin A1c; HbA1c, fasting glycemia and oral glucose tolerance test) were investigated in 10 patients with newly diagnosed primary nephrotic syndrome and 10 healthy subjects. EFF was determined in order to avoid variables depending upon plasma, white cells and hematocrit. The mean level of HbA1c was higher in the nephrotic group, in which we found 4 patients with impaired glucose tolerance according to the criteria of the National Diabetes Data Group. EFF was lower in nephrotic patients than in controls and correlated inversely with HbA1c. These findings indicate that nephrotic patients have a reduced red cell deformability which seems to be related to the abnormal carbohydrate metabolism commonly observed in this syndrome.

Adult↗

Clinical significance of positive direct antiglobulin test in patients with HIV infection.

A direct antiglobulin test (DAT) was performed in 70 patients with anti-HIV antibodies (group A: seropositive patients without or with minimal disease and group B: AIDS patients with or without malignancies). A positive DAT was found in 24 of 70 patients (34%, significantly higher compared to 0.1% in healthy controls) and a higher prevalence of positive DAT was observed in group B than in group A patients (55% versus 21% p < 0.01). When comparing DAT-positive and negative patients within the same clinical group, no significant difference is seen in haemoglobin levels. There is no difference in serum bilirubin, haptoglobin or reticulocyte count between DAT-positive and negative patients altogether or in the same clinical group. AZT therapy seems to exert no significant influence on the onset of a positive DAT. The results confirm a high prevalence of positive DAT in patients with HIV antibodies, mainly in worse clinical conditions, and suggest that a positive DAT might be a prognostic factor in the clinical course of the disease.

Adult↗

Prevention of radiotherapy-induced emesis.

The severity of nausea and vomiting in patients undergoing radiotherapy is lower than that associated with chemotherapy regimens, but its duration may be considerably longer. Total body irradiation and irradiation of the upper part of the abdomen or whole abdomen are considered the most emetogenic regimens in radiotherapy. Instead, the emetogenic potential is considered moderate in radiotherapy of the thorax, pelvis and lower half-body irradiation, and low in radiotherapy of head and neck, extremities, brain and skin. In contrast to the very extensive literature on the prevention of chemotherapy-induced emesis, relatively few studies have been published on patients submitted to radiotherapy. Metoclopramide, prochlorperazine and cannabinoids offer only limited symptom control in patients undergoing radiotherapy of moderate to severe emetogenic potential. Double-blind randomized studies showed the superior antiemetic efficacy of the 5-HT3 antagonists with respect to placebo and to the older antiemetic drugs in patients submitted to single dose or fractionated doses of radiotherapy to the upper abdomen, to lower hemibody radiotherapy and to total body irradiation. In all these cases the 5-HT3 antagonists should be considered the antiemetic treatment of choice and should be administered as prophylactic agents. The optimal duration of antiemetic therapy with the 5-HT3 antagonists is unknown. Whether corticosteroids added to the 5-HT3 antagonists will increase their antiemetic efficacy, as in chemotherapy-treated patients, remains to be demonstrated in double-blind controlled trials. Patients submitted to radiotherapy of low emetogenic risk do not require any antiemetic prophylaxis. In this case a rescue antiemetic treatment can be administered if patients present vomiting or moderate to severe nausea.

Antiemetics↗

[Quality control of spirometric tests used in health surveillance for occupational exposure risk, in the province of Viterbo].

A quality control survey on spirometry assessments carried out in a number of factories in the province of Viterbo (Lazio Region) was made by the Local Health Unit in Viterbo, as required by law 626/94 on the promotion of workers health. The survey concerned 734 measurements concerning the same number of employees from 29 different factories. Each spirometry assessment was repeated in this study according to the quality standards defined in the literature and our own results were compared with the values which had been obtained over one year during the health surveillance program (ASP). A few main functional parameters were considered according to the following criteria: percentage of agreement (tolerance +/- 5%) between the two FVC, FEV1 and FEF25-75 measures or degree of discrepancy; for FEV1/FVC ratio, the occurrence of < 70 (suggestive of an obstructive lesion) and > 90 values (reflecting poor reliability in the measurement of the lung volumes) in the two sets of data. Further criteria concerned the comparison of the height of the individuals (tolerance range +/- 1 cm), and the comparison of the overall spirometry rating expressed as the number of tests rated normal or abnormal (during the first assessment as compared to the second). The results show poor agreement (11.4%) for FVC with as many as 85.8% underestimated values; 30.1% agreement and 64.2% underestimate for FEV1; 17% agreement and 53.5% overestimate for FEF25-75. There were 6.5% fewer < 70 FEV1/FVC ratios, and 18.3% more > 90 ratios in the tests carried out in the factories as compared to our own. There was 32.9% agreement on the height, with overestimation in 63.7% of the cases. There were 12.3% "false abnormal" and 2.6% "false normal" results in the overall rating of the spirometry (as carried out by the factories compared to our own). In conclusion, the survey revealed a trend in the measurements carried out by the factories to underestimate the volumes, overestimate the flows, improperly select the theoretical reference values because of a mistake in measuring the height, to overestimate restrictive abnormalities, and underestimate the obstructive ones.

Adult↗

[SLE: Extra-renal clinical manifestations and lupus nephritis].

Systemic Lupus Erythematosus (SLE) is a chronic inflammatory autoimmune disease affecting multiple organ systems, skin and joints the most involved. Lupus Nephritis occurs in Approximately 50% of patients, sometimes it may be the first manifestation of SLE. Clinical features range from asymptomatic urinary abnormalities to full-blown nephrotic syndrome or rapidly progressive renal failure. Because of the heterogeneity of clinical renal manifestations, renal biopsy plays an important role in the management of patients with SLE: it provides information about the class, severity, activity and chronicity of the renal disease that cannot be accurately predicted on the basis of clinical parameters. The complexity of protean renal manifestation of SLE can be approached using the original WHO classification (1982), recently revised (2004).

Humans↗