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Biomedical subjects

S Rizzo

Publications and source records attributed to S Rizzo.

At least 19 recordsLinked to original sources
PubMed2003

Memory and executive functions in aneurysms of the anterior communicating artery.

The cognitive outcome of three groups of patients, who had undergone surgery for repair of a single ruptured intracranial aneurysm, was evaluated. We assessed performance on tests of executive functions and memory in a group of 15 patients tested at least 3 months after an aneurysm of the anterior communicating artery (ACoA) and in a group of 12 patients tested in the first month after the same pathology. Acute patients were more impaired overall than chronic ones, but the two groups significantly differed on two executive and one memory test. The performance of the ACoA patients was also compared to the performance of a group of 10 patients who had undergone surgery for an aneurysm located on the posterior communicating artery (PCoA) at least 3 months before the examination. Chronic ACoA and PCoA patients significantly differed in two memory and in two executive tests performance, with posterior patients being more impaired than anterior. An unexpected finding was the impairment of semantic memory in ACoA patients.

Adult↗
PubMed2002

Famous face recognition and naming test: a normative study.

Tests of famous face recognition and naming, and tasks assessing semantic knowledge about famous people after presentation either of their faces or their names are often used in the neuropsychological examination of aphasic, amnesic and demented patients. A total of 187 normal subjects took part in this study. The aim was to collect normative data for a newly devised test including five subtests: famous face naming, fame judgement after face presentation and after name presentation, semantic knowledge about famous people after face presentation and after name presentation. Norms were calculated taking into account demographic variables such as age, sex and education and adjusted scores were used to determine inferential cut-off scores and to compute equivalent scores. Multiple regression analyses showed that age and education influenced significantly the performance on most subtests, but sex had no effect on any of them. Scores of the subtest evaluating fame judgements after name presentation were significantly influenced only by education. The only subtest whose scores were not influenced by any demographic variable was fame judgement after face presentation.

Adult↗
PubMed2002

Environmental radioactivity at Stromboli (Aeolian Islands).

HPGe gamma spectrometry, thermoluminescence dosimetry, X-ray diffractometry and fluorescence techniques have been used to analyze the natural radionuclides content of soil and rock samples, air kerma and geochemical features on the island of Stromboli, belonging to the Aeolian Islands, in the Mediterranean Sea. The 214Bi, 238Ac, and 40K contents obtained are in agreement with the magmatic evolution of the rock formation, as shown by the correlations between radionuclide and chemical elements abundacies, depending on the various magmatic differentiation mechanisms. Correlations between radiometric, lithological and geochemical data have been assessed in order to obtain some hints on the geochronology of the magmatic products.

Journal Article↗
PubMed2002

Analysis of radioactive pollution in the Gulf of Palermo.

PURPOSE: Sea water represents more than three quarters of the whole world. The radioactive fall out caused by nuclear experiments, radioactive drosses from nuclear power plants and other pollution sources, are able to contaminate the world ecosystems, and especially the sea water. The aim of this work is the evaluation of a possible radioactive pollution in the Gulf of Palermo. MATERIAL AND METHODS: The Gulf of Palermo was divided into 5 homogeneous hydrological parts, in which fish and water were collected. The dosage of 131I e del 137Cs was mainly assessed because they have a long half-life and their presence in the water can be due to nuclear accidents but also to a wrong removal of the waste materials of nuclear medicine procedures; the other radioisotopes assessed (144Ce, 106Rh, 140La) are due only to nuclear fall-out. Gamma spectrometry technique was used for the evaluation of the radioisotopes' concentration after an adequate treatment of the samples. RESULTS AND CONCLUSIONS: The concentration of the examined radionuclides was below the instrumental capability apart from the 137Cs, whose dose was increased, and can be due to nuclear accidents and explosions. The radionuclide levels detected do not determine a higher risk than normal for the population's health even regard the eatablity of ittical species.

Animals↗
PubMed2002

[Balance disorders in the elderly].

In the elderly patient, instability is a syndrome in which a loss of balance, during ambulation or while standing, can give rise to falls, with consequent disability and morbidity. Maintaining the correct static and dynamic balance is known to be the result of the synergetic functioning of different systems. In old age, however, the efficiency of these mechanisms is impaired because of the physiological process of aging, which affects all of the organs and systems of the human body. Besides that, different concomitant causes such as cardiovascular and dysmetabolic pathologies, chronic pharmacological therapies etc. contribute to the aging of our organism. The object of this study was to evaluate 40 subjects, 21 males and 19 females, aged between 70 and 86, who were referred to us with craniofacial trauma consequent to a fall. Upon hospitalization, all of the patients were asked to fill in a questionnaire evaluating the incidence of the vertigo symptom as a possible cause of the falls. All of the subjects underwent the following clinicoinstrumental examinations: standard audiometric evaluation, vestibular tests, neurological and ophthalmic examination. Careful appraisal of the results obtained enabled us to conclude that balance disorders in the elderly patient are due to the synergetic action of three factors: aging, concomitant diseases and environmental factors. In conclusion, we can affirm that balance disorders giving rise to a fall in the elderly are attributable to the concomitance of different factors that determine a clinical state of imbalance, defined by some Authors with the term "presbivertigo". It follows that a suitable diagnostic protocol must be employed, comprising a detailed medical, pharmacological and functional history, a study both of the environmental conditions in which the patient lives and the modalities according to which the traumatic event occurred. It is, last of all, indispensable that steps be taken to improve these environmental conditions, such as choosing flooring materials, light fixtures, stairs, bathroom furnishings and suitable footwear promoting proper foot placement and support on the ground.

Aged↗
PubMed2001

Temporary graft for closed-system cataract surgery during corneal triple procedures.

Performing phacoemulsification during a triple corneal procedure has many advantages. Operating in a closed chamber makes surgery easier and safer. In some cases, however, a dense corneal opacity may prevent closed-chamber surgery, necessitating the use of an open-sky technique. In these cases, a temporary corneal graft using a corneal button not suitable for penetrating keratoplasty is proposed to allow phacoemulsification and foldable intraocular lens implantation through a corneal tunnel. The temporary corneal graft is replaced with a permanent graft after these steps are completed. This technique was effective in 3 patients with cataract and dense corneal opacity.

Cataract↗
PubMed2001

Seasonal variation of air kerma in the "Vulcano Porto" area (Aeolian Islands, Italy).

Air kerma was measured in the "Vulcano Porto" area of the Vulcano Island, belonging to the Aeolian Islands, in the Mediterranean Sea. Measurements were carried out using thermoluminescence dosimeters. The relationship between observed dose values and source lithology has been assessed. Data show a seasonal variation due to weather conditions but also probably related to features of the soils, making the variation more evident.

Air↗
PubMed2001

Gamma activity and geochemical features of building materials: estimation of gamma dose rate and indoor radon levels in Sicily.

A high-purity germanium detector has been used to measure the abundance of radium (Ra), thorium (Th) and potassium (K) in building materials used in Sicilian dwellings. The measurements were performed to evaluate which material was suitable for the construction of an enclosure, which would have a low background emission. The materials examined in this work showed concentrations of 226Ra, 232Th and 40K dramatically variable depending on the lithologies, particularly in the case of blocks, sands and aggregates commonly used in building materials in Sicily. The results are discussed and a criterion is indicated to reduce the radiation dose to humans. Since radon inlet is a major health problem, all the radiometric data and the geochemical features have been used to determine the radon exhalation, which arises from the disintegration of 226Ra in soils and walls of houses. From our experimental data it can be seen out that one of the geochemical parameters, Total Alkali (TA), may be an appropriate index to select materials of low radiological risk.

Algorithms↗
PubMed2001

[Large thrombus in non-aneurysmal descending aorta and peripheral embolism: report of a case and review of the literature].

We describe the case of a middle-aged woman with massive thrombosis of the aortic bifurcation, treated with emergency surgery. The patient was later evaluated by transthoracic echocardiography, which resulted normal, and by transesophageal echocardiography, which demonstrated a huge thrombus in the lumen of the descending thoracic aorta, in the absence of gross vessel wall abnormalities. Thus, the patient underwent a second surgical intervention and the thrombus was successfully removed. The episode led us to review the medical literature about cases of thrombosis and embolization originating from macroscopically normal aortas. This review underscores the diagnostic yield of the transesophageal study of the aorta in patients with systemic embolization (particularly in the presence of risk factors for atherosclerosis) and supports a wider indication of transesophageal echocardiography in the evaluation of systemic embolizating syndromes.

Aorta, Thoracic↗
PubMed2001

[False mass in the left atrium... or better: true mass in false atrium].

We report the case of a 59-year-old man who underwent transesophageal echocardiography following a cryptogenic minor stroke. An image of a solid mass of the left atrial appendage, highly suggestive of a thrombus, was observed. The patient was treated for 10 weeks with oral anticoagulants. Because of the absence of changes in the echocardiographic appearance of the mass at follow-up, the patient was submitted to surgery. At surgical exploration no endocavitary thrombus was found, but the left atrial appendage appeared hypoplastic and dysmorphic. A biopsy was taken and the left atrial appendage was plicated. To our knowledge, this is the first report of a case of dysmorphism of the left atrial appendage mimicking a left atrial thrombus in a patient with cryptogenic minor stroke.

Atrial Appendage↗
PubMed2000

3,3'-Bis(diphenylphosphino)-1,1'-disubstituted-2,2'-biindoles: easily accessible, electron-rich, chiral diphosphine ligands for homogeneous enantioselective hydrogenation of oxoesters

Racemic (+/-)-3,3'-bis(diphenylphosphinyl)-1,1'-dimethyl-2, 2'-biindole (1c) (N-Me-2-BINPO) and (+/-)-3, 3'-bis(diphenylphosphinyl)-1,1'-bis(methoxymethyl)-2,2'-biindole (1d) (N-MOM-2-BINPO) were synthesized in satisfactory yields following a three-step reaction sequence, starting from indole. Resolution of racemic 1c and 1d was achieved through fractional crystallization of their diastereomeric adducts with optically active dibenzoyl tartaric acids, followed by alkaline decomplexation of the diastereomerically pure salts. Their trichlorosilane reduction gave enantiopure phosphines (+)- and (-)-(1a) (N-Me-2-BINP) and (+)- and (-)-(1b) (N-MOM-2-BINP). The electrochemical oxidative potential of 1a and 1b was found to be 0. 52 and 0.60 V, respectively. Both the enantiomers of (1a) were tested as ligands of Ru(II) in asymmetric hydrogenation reactions of alpha- and beta-oxoesters. Reactions were found to be outstandingly fast and enantioselection quite good. Comparative kinetic experiments on the hydrogenation reaction of methyl acetoacetate carried out with 1a, 1c, BINAP, and other biheteroaromatic diphosphines as ligands of Ru(II) demonstrated that all the reactions follow a first-order kinetic. A linear relationship was found between the kinetic constant log and the electrochemical oxidative potential of the diphosphine ligand.

Journal Article↗
PubMed2000

Assessment of bone marrow stem cell reserve and function and stromal cell function in patients with autoimmune cytopenias.

To investigate whether bone marrow (BM) stem cell compartment and/or BM microenvironment are affected by the immune insult in autoimmune cytopenias (AICs), BM stem cell reserve and function and BM stromal function were studied in 15 AIC patients. Stem cells were evaluated by means of flow cytometry, clonogenic progenitor cell assays, long-term BM cultures (LTBMCs), and limiting dilution assay for quantification of long-term-culture initiating cells (LTC-ICs). Stromal cell function was assessed with the use of preformed irradiated LTBMCs from patients and normal controls, recharged with normal CD34(+) cells. AIC patients exhibited a high number of CD34(+), CD34(+)/CD38(+), and CD34(+)/CD38(-) cells; high frequency of granulocyte-macrophage colony forming units in the BM mononuclear cell fraction; high colony recovery in LTBMCs; and normal LTC-IC frequency. Patient BM stromal layers displayed normal hematopoietic-supporting capacity and increased production of granulocyte-colony stimulating factor. Data from this study support the concept that AIC patients with severe, resistant disease might be appropriate candidates for autologous stem cell transplantation.

ADP-ribosyl Cyclase↗
PubMed2000

Glucocorticoids promote the proliferation and antagonize the retinoic acid-mediated growth suppression of Epstein-Barr virus-immortalized B lymphocytes.

Glucocorticoids are able to release Epstein-Barr virus-immortalized (EBV-immortalized) lymphoblastoid B cell lines (LCLs) from the persistent growth arrest induced in these cells by retinoic acid (RA). Moreover, physiologic concentrations of glucocorticoids efficiently antagonized LCL growth inhibition induced by 13-cis-RA; 9-cis-RA; all-trans-RA; and Ro 40-6055, an RA alpha receptor (RAR alpha) selective agonist. RAR alpha expression levels, however, were not affected by glucocorticoids. Glucocorticoids, but not other steroid hormones, directly promote LCL proliferation, a phenomenon that was mainly mediated by down-regulation of the cyclin-dependent kinase (CDK) inhibitor p27(Kip-1). Moreover, glucocorticoids contrasted the up-regulation of p27(Kip-1), which was underlying the RA-induced LCL growth arrest, thereby indicating that glucocorticoids and RA signalings probably converge on p27(Kip-1). Both antagonism of RA-mediated growth inhibition and promotion of LCL proliferation were efficiently reversed by the glucocorticoid receptor (GR) antagonist RU486, indicating that all of these effects were mediated by GR. Of note, RU486 also proved to be effective in vivo and, in mice, was able to significantly inhibit the growth of untreated LCLs as well as LCLs growth-arrested by RA in vitro. These findings provide a rational background to further evaluate the possible role of glucocorticoids in the pathogenesis of EBV-related lymphoproliferations of immunosuppressed patients. Moreover, GR antagonists deserve further consideration for their possible efficacy in the management of these disorders, and the use of schedules, including both RA and a GR antagonist, may allow a more thorough evaluation of the therapeutic potential of RA in this setting. (Blood. 2000;96:711-718)

Animals↗
PubMed2000

Retinoic acid induces persistent, RARalpha-mediated anti-proliferative responses in Epstein-Barr virus-immortalized b lymphoblasts carrying an activated C-MYC oncogene but not in Burkitt's lymphoma cell lines.

We have previously demonstrated that 13-cis-retinoic acid (RA), 9-cis-RA and all-trans-RA (ATRA) powerfully inhibit the proliferation of Epstein-Barr virus-immortalized B-lymphoblastoid cell lines (LCLs). The aim of the present study was to assess whether these compounds are effective at inhibiting the growth of B cells at more advanced stages of lymphomagenesis, including fully transformed B lymphocytes. To this end, c-myc-transfected LCLs (myc-LCLs) and Burkitt's lymphoma (BL) cell lines were used. We report that 13-cis-RA, 9-cis-RA and ATRA also markedly inhibit the proliferation of myc-LCLs by inducing G(0)/G(1) growth arrest as well as enhancing rates of apoptosis. Conversely, all but 1 (DG75) of the 8 BL cell lines investigated were poorly RA-responsive. Moreover, unlike LCLs and myc-LCLs, RA-treated DG75 cells rapidly resumed proliferation upon drug removal. Analysis of cell cycle-regulatory proteins showed that, as in LCLs, strong up-regulation of p27(Kip-1) and increased levels of under-phosphorylated pRb and p130 were detected in RA-treated DG75 cells. While the catalytic activity of all 3 G(1)-associated CDKs (CDK2, CDK4 and CDK6) was strongly inhibited in RA-treated LCLs, only CDK2-associated kinase activity was reduced in DG75 cells arrested in G(0)/G(1) by RA. Moreover, RA-treated DG75 cells failed to show the down-regulation of cyclin D3 observed in LCLs. Use of receptor-selective agonists and antagonists showed that in LCLs and RA-responsive BL cells, RA-induced growth arrest is mainly mediated by RARalpha. The RARalpha-selective agonist Ro 40-6055 was also effective at very low concentrations (10(-10) M). Nevertheless, comparable levels of RARalpha mRNA were found in RA-responsive and -resistant BL cell lines, indicating that mechanisms different from transcriptional deregulation of RARalpha probably underlie the differential responsiveness of BL cells.

Antineoplastic Agents↗
PubMed2000

Reasons for use of hormone replacement therapy in women undergoing coronary angiography.

The recommendation has been made that all women be counseled about the risks and benefits of hormone replacement therapy (HRT). Use of HRT among women undergoing coronary angiography was explored to assess whether patterns of use were similar to data drawn from community samples. Using a descriptive design, a convenience sample of 414 postmenopausal women was interviewed. Fifty-eight percent had never used HRT, 18.3% were past users, and 23.7% were currently using HRT. The primary reason given for ever using HRT was for symptoms of menopause. Less than 14% of women cited coronary heart disease (CHD) or osteoporosis as their primary reason for using HRT. The most common reasons for stopping HRT were side effects and fear of cancer. The most common reasons given for never having used HRT were that their healthcare provider had never talked about it and that they had never thought about it. Use of HRT among women undergoing coronary angiography is similar to that found in community samples. The challenge is to promote patient-provider interactions that include information about HRT based on the scientific model as well as attention to women's individual concerns.

Adult↗