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Biomedical subjects

A Rizzo

Publications and source records attributed to A Rizzo.

At least 19 recordsLinked to original sources
PubMed2006

A novel method for preparing and characterizing alcoholic EPD suspensions.

Ceramic suspensions composed of alumina and mixtures of alumina and zirconia powders in ethyl alcohol were prepared. A solution of citric acid and triethylamine was used as dispersant. The citric acid, which usually is used as dispersant in water alumina suspensions, gave excellent results in ethyl alcohol also if it was used in conjunction with triethylamine. A novel method consisting of combined measurements of grain size, zeta potential, and transmittance was optimized to study the dispersion and stability properties of the ceramic suspensions; by using this method the optimal dispersant amount was determined. The suspensions based on alumina and alumina-zirconia powders were used to coat stainless steel plates by electrophoretic deposition (EPD); the optimal composition of suspensions and the used EPD parameters made it possible to obtain coatings with uniform thickness and composition.

Journal Article↗
PubMed2006

Fatal necrotising fasciitis associated with intramuscular injection of nonsteroidal anti-inflammatory drugs after uncomplicated endoscopic polypectomy.

Necrotising fasciitis is a life-threatening infection of the superficial muscle fascia and the adjacent deep layer of subcutaneous tissue that is often fatal. A 46-year-old woman was admitted to the intensive care unit (ICU) three days after an uncomplicated endoscopic polypectomy because of necrotising fasciitis of left tight, buttock and retroperitoneal space and septic shock. Six hours after the polypectomy she was given an intramuscular injection of ketorolac in the left tight because of moderate low abdominal pain. Twelve and 24h later she was treated with another two intramuscular injection of diclofenac in the left tight for severe pains in the left hip joint region. The shock was unresponsive to any treatment and the fasciitis extended to the whole body even after surgical specific treatment and the patient died in four days. This is the first report of a necrotising fasciitis following intramuscular administration of nonsteroidal anti-inflammatory drugs after an endoscopic procedure.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2006

Concentrations of free radicals and beta-endorphins in repeat breeder cows.

Repeat breeding (RB) is one of the major problems that affect the reproductive efficiency and economy of milk production in dairy animals. So far, the etiopathogenesis of this pathology has not been defined completely. Stress has been hypothesized to be a cause of impaired reproductive efficiency. Stress may cause an overproduction of beta-endorphins and free radicals; in particular, reactive oxygen species (ROS). The aim of this work is to determine the concentrations of these substances in RB cows and to evaluate the correlation with the serum level of progesterone. The study was performed on 60 dairy cows: 26 RB and 34 control cows. Blood samples were collected on day 12 and day 16, after artificial insemination (AI) in all subjects, in order to assess the concentrations of progesterone, free radicals and beta-endorphins. The stressors, free radicals and beta-endorphins, that we considered, were higher in repeat breeders (day 12, 93.32(+/-1.91) UCarr and 0.50(+/-0.03) ng/ml; day 16, 94.42(+/-1.91) UCarr and 0.61(+/-0.03) ng/ml), with a lower level of progesterone, which probably is responsible for failure to conceive. The stress factors (free radicals and beta-endorphins) may actually enhance each other and induce an inhibition of progesterone synthesis in repeat breeders.

Animals↗
PubMed2006

Solvent effects on the conformational distribution and optical rotation of gamma-methyl paraconic acids and esters.

A computational investigation of the optical rotatory power of cis and trans 2-methyl-5-oxo-tetrahydro-3-furancarboxylic acids and the corresponding methyl and ethyl esters is presented. Solvent effects on both the conformational space and the rotatory power are analyzed by comparing results obtained in vacuo with those computed--using the Polarizable Continuum Model--in methanol. A comparison with experimental observations for the optical rotatory power of the title compounds in methanol is also carried out, in a few cases also for several wavelengths. Agreement between theory and experiment is in all cases excellent, in particular when solvent effects are included both in the geometry optimization and in the calculation of the OR, thus confirming the validity of the computational procedure adopted, even for this challenging family of floppy molecules.

Journal Article↗
PubMed2006

Rhodotorula mucilaginosa outbreak in neonatal intensive care unit: microbiological features, clinical presentation, and analysis of related variables.

Reported here are the features of a Rhodotorula mucilaginosa outbreak that occurred in a neonatal intensive care unit. Over a period of 19 days, clinical and laboratory signs of sepsis appeared in four premature infants carrying indwelling vascular catheters. After bloodstream infection with R. mucilaginosa was ascertained, the patients underwent amphotericin B therapy and recovered completely. In a retrospective case-control study, the variables displaying a statistical difference between case and control-group neonates were birth weight, gestational age, duration of parenteral nutrition, duration of antibiotic therapy and prophylactic administration of fluconazole. To our knowledge, this is the first reported outbreak caused by yeasts of the Rhodotorula genus.

Amphotericin B↗
PubMed2005

Relationship between Chlamydia pneumoniae infection, inflammatory markers, and coronary heart diseases.

Chlamydia pneumoniae is an intracellular pathogen and an important cause of respiratory tract infections in humans and more recently it has been associated with chronic diseases such as atherosclerosis. Numerous studies have been performed to show the "infectious" hypothesis of atherosclerosis by direct detection of the organisms within atheromatous plaques by seroepidemiological estimation and by animal, immunological and antibiotic interventional studies. In this work we investigated the relation between chronic chlamydial infection, inflammatory markers, Interleukin 7 (IL-7) production and coronary heart disease. We studied 60 patients with coronary heart diseases (CHD), 45 of whom were men and 15 women, with a mean age of 65+/-5 years, and a control group of 20 healthy subjects, 15 men and 5 women, with a mean age of 60+/-7 years. Detailed histories including symptoms, risk factors and demographic data were obtained from patients and healthy subjects by administering a standardized questionnaire. Our results demonstrate that the enzyme-linked immunoassay (ELISA) test appears to have a greater sensitivity than the microimmunofluorescence (MIF) technique. 80% of patients had positive IgG to C. pneumoniae and 58% positive IgA to C. pneumoniae with ELISA, while the MIF test showed 68% and 55% positive IgG and IgA to C. pneumoniae, respectively. The control subjects showed 55% positive IgG and 10% IgA to C. pneumoniae by ELISA and 35% positive IgG and 5% IgA to C. pneumoniae by MIF. The combination of positive IgG and IgA to C. pneumoniae was present more frequently than in the control group. Serum levels of IL-7 measured by ELISA were also significantly higher in patients compared to healthy subjects. In conclusion, our study shows that C. pneumoniae IgG and IgA seropositivity, inflammatory markers such as IL-7, fibrinogen, C-reactive protein were significantly correlated with CHD.

Aged↗
PubMed2005

Involvement of hTERT in apoptosis induced by interference with Bcl-2 expression and function.

Here, we investigated the role of telomerase on Bcl-2-dependent apoptosis. To this end, the 4625 Bcl-2/Bcl-xL bispecific antisense oligonucleotide and the HA14-1 Bcl-2 inhibitor were used. We found that apoptosis induced by 4625 oligonucleotide was associated with decreased Bcl-2 protein expression and telomerase activity, while HA14-1 triggered apoptosis without affecting both Bcl-2 and telomerase levels. Interestingly, HA14-1 treatment resulted in a profound change from predominantly nuclear to a predominantly cytoplasmic localization of hTERT. Downregulation of endogenous hTERT protein by RNA interference markedly increased apoptosis induced by both 4625 and HA14-1, while overexpression of wild-type hTERT blocked Bcl-2-dependent apoptosis in a p53-independent manner. Catalytically and biologically inactive hTERT mutants showed a similar behavior as the wild-type form, indicating that hTERT inhibited the 4625 and HA14-1-induced apoptosis regardless of telomerase activity and its ability to lengthening telomeres. Finally, hTERT overexpression abrogated 4625 and HA14-1-induced mitochondrial dysfunction and nuclear translocation of hTERT. In conclusion, our results demonstrate that hTERT is involved in mitochondrial apoptosis induced by targeted inhibition of Bcl-2.

Apoptosis↗
PubMed2004

Severe acute colitis associated with CMV: a prevalence study.

BACKGROUND: Cytomegalovirus has been identified as a pathogen that contributes to flares of colitis when detected in colonic specimens of patients with inflammatory bowel disease. AIM: To determine the overall prevalence and the role of cytomegalovirus infection in a consecutive series of patients with acute severe colitis admitted to our department from 2000 to 2003. METHODS: Among 42 patients (38 with ulcerative colitis and 4 with Crohn's disease) admitted to our hospital for acute severe colitis, we performed proctoscopy and biopsy together with blood sample for cytomegalovirus determination at the time of admission, regardless of their steroid resistance. RESULTS: In the 42 patients, we discovered an overall cytomegalovirus infection prevalence of 21.4% (9/42) in our geographical area. In seven patients (16.6%), cytomegalovirus was detected through biopsy. The presence of cytomegalovirus in biopsies was not always predictive of steroid resistance. Three patients with cytomegalovirus in biopsies responded to conventional treatment without needing any antiviral treatment, which suggests that the virus plays only an incidental role. CONCLUSIONS: Cytomegalovirus is frequently associated with colitis but it is not always pathogenic. Studies on the genotyping of the virus might explain the diversity of its biological behaviour.

Adult↗
PubMed2004

Commonly used antibiotics induce expression of Hsp 27 and Hsp 60 and protect human lymphocytes from apoptosis.

Heat shock proteins (Hsps) are abundant molecular chaperones participating in the cytoprotection. The kinetics of synthesis of Hsps closely correlates with the kinetics of development of resistance to cell death. In this study, we analysed the probable involvement of Hsp 27 and Hsp 60 in the protection of cells undergoing apoptosis. Human lymphocytes cultured in the presence of ampicillin or ceftriaxone produced Hsp 60 and Hsp 27, estimated by immunoblotting in a time-dependent manner and the increased levels of Hsp 60 and Hsp 27 correlated with enhanced resistance of the lymphocytes to apoptosis, as determined by flow cytometry. Cultures treated with ampicillin or ceftriaxone also exhibited smaller numbers of apoptotic cells than untreated cultures when exposed to the apoptosis-inducing agent staurosporine (1 mM). In contrast, cloramphenicol induced the production of only small amounts of Hsp 60, and no resistance apoptosis. Further studies are needed to clarify the potential role of Hsp 27 and Hsp 60 in the resistance of human cells to apoptosis and the effects of antibiotics on this phenomenon.

Adjuvants, Immunologic↗
PubMed2004

Presence and concentrations of the Fusarium-related mycotoxins beauvericin, enniatins and moniliformin in finnish grain samples.

Fusarium mycotoxins beauvericin, enniatins (A, A1, B, B1) and moniliformin were analysed in 38 Finnish grain samples (14 wheat, 22 barley, one rye, one oats) harvested in 2001-02. The contaminating Fusarium species were identified with the primer-specific polymerase chain reaction as well as with morphological studies. All the studied mycotoxins were found in the samples. Enniatins B and B1 were detected in all samples, and enniatin A, enniatin A1, beauvericin and moniliformin in 74, 95, 95 and 74% of the samples, respectively. There were higher concentrations of the mycotoxins analysed in 2001 compared with 2002. The highest levels of mycotoxins were detected in samples harvested late in the autumn after a long rainy period. Fusarium avenaceum was the most abundant Fusarium species in Finland during both years (0-29.5%) measured as infected kernels. A significant correlation was found between F. avenaceum contamination level and the concentration levels of enniatins B and B1, as well as moniliformin.

Cyclobutanes↗
PubMed2004

Hippocampal gene expression is modulated by hypergravity.

We used the cDNA microarray technique to monitor simultaneously possible changes induced by hypergravity in the expression level of thousands of hippocampal genes. We tested the mRNA level of about 5000 genes in the hippocampus of mice subjected to 1.09 g (1g) or to 1.85 g (2g) for five repeated 1-h daily rotations in a centrifuge (g = 9.81 m/s2). Data were compared with those obtained for mice kept stationary (C). The ratios 1g/C and 2g/C identified genes affected by rotation and rotation + hypergravity, respectively, whereas 2g/1g ratio identified those affected by hypergravity. We found that about 200 genes were affected by rotation and/or rotation + hypergravity. Almost all the genes affected by rotation + hypergravity were up-regulated, only five being down-regulated. The modulated genes code for proteins involved in a wide range of cellular functions (DNA/RNA metabolism, protein processing, intermediate metabolism, cytoskeleton and motility, cell cycle and apoptosis, signal transduction, neuronal structure/function), suggesting that rotation + hypergravity may affect several aspects of the hippocampal function in order to compensate for environmental changes. Six genes directly or indirectly involved in synaptic transmission and plasticity (proSAAS, neuroblastoma ras oncogene, ESTs moderately similar to thymosin beta-10, syndet, inhibin beta E and Ngfi-A binding protein 2) were found to be significantly modulated by hypergravity and unaffected or only slightly affected by rotation. The modulation by hypergravity of these genes suggests that this stimulus might induce plastic remodelling of the hippocampal circuits, possibly both at structural and functional level.

Animals↗
PubMed2002

Chlamydia pneumoniae infections prevent the programmed cell death on THP-1 cell line.

Chlamydia pneumoniae is an obligate intracellular bacterium which frequently causes airway infection in humans and has been implicated in chronic inflammatory disease and atherosclerosis. Here we show that infection with C. pneumoniae protects THP-1 cells against the apoptosis which spontaneously occurs in macrophages in the absence of an activation signal. Analysis by flow cytometry at different post-infection times revealed that 50+/-7% of THP-1 cells were apoptotic at 48 h after onset of the experiments, whereas C. pneumoniae-infected cultures (multiplicity of infection, MOI=30) displayed only 18+/-4% of cells in apoptosis. At MOI=20 and MOI=10 the cells susceptible to apoptosis at 48 h were 28+/-5% and 35+/-6% respectively. Moreover, the results show that heat-inactivated bacteria do not give significant protection against apoptosis, even at higher MOI (MOI=30), while UV-treated Chlamydia did provide a degree of protection against apoptosis. These data suggest that the anti-apoptotic effect of C. pneumoniae requires a heat-labile component released during infection, and that the effect is not lipopolysaccharide-dependent.

Apoptosis↗
PubMed2002

Comparison of two nimodipine formulations in healthy volunteers.

The objective of this study was to assess the pharmacokientic parameters of regular nimodipine (Bayer), 30 mg, given every 6 h and nimodipine AP (nimodipine in micro particles with programmed action contained in tablets, developed by Biocontrolled-Leti Group Laboratories), 120 mg, given every 24 h. Subjects (19 healthy volunteers, five female; 14 male: age: 21 +/- 0.7 years) received one formulation over 5 days. Then, after a washout period of 7 days, the other formulation was given. The analyst was blinded to the relationship in formulation received. Antecubital blood samples were taken before the first tablet was taken and after 15, 45, 60 min and 2, 4, 6, 8, 12, 13, 18 and 24 h on day 1 and five of each formulation. Nimodipine blood levels were analysed by HPLC. At steady-state regular nimodipine reached a C-max of 10.208 +/- 0.317 ng/ml, at a t-max of 1 h; minimum concentration 6 h after dosage was 1.2929 +/- 0.411 ng/ml, half-life was estimated in 2.9 h. Meanwhile nimodipine AP 120 mg reach a C-max of 11.885 +/- 0.403 ng/ml; a t-max of 1 h with a minimum concentration 24 h after the last dose of 4.2387 +/- 0.353 ng/ml (P < 0.001). Apparent half-life was calculated in 17.8 h (P < 0.001). Area under the curve for the 24 h period was 143.76 ng/ml/min for regular nimodipine and 183.7 ng/ml/min for nimodipine AP 120 mg (P < 0.001), indicating better bioavailability. In conclusion nimodipine in AP formulation 120 mg produced similar peak plasma levels (C-max) than regular nimodipine, but with higher trough (C-min) values and stable plasma levels with one administration every 24 h. This formulation would be more suitable when nimodipine chronic therapy is indicated.

Adult↗
PubMed2002

Localized unresectable neuroblastoma: results of treatment based on clinical prognostic factors.

BACKGROUND: We previously reported that stage 3 neuroblastoma comprises (i) a low-risk group including all infants (age 0-11 months) as well as older children with non-abdominal primaries, and (ii) a high-risk group made up of children >1 year of age with abdominal primaries. Aggressive chemotherapy was effective only in the latter group. PATIENTS AND TREATMENT: On this basis, in 1990 we designed a new protocol by which all low-risk patients received standard-dose chemotherapy, while the high-risk ones received very aggressive chemotherapy. RESULTS: Between November 1990 and December 1997 a total of 95 eligible and evaluable children were enrolled: 47 were low-risk (35 infants and 12>1 year of age at diagnosis and having non-abdominal primaries), and 48 were high-risk (being >1 year of age and having abdominal primaries). Of the 47 low-risk patients, five relapsed and four subsequently died. The 5-year overall survival (OS) was 91%. Of the 48 patients in the high-risk group, 22 relapsed or progressed, 18 of whom died from their disease and two from toxicity, and one was lost to follow-up. The 5-year OS was 60%. Univariate analysis showed that age, site of primary, risk-group, urine vanillylmandelic excretion, plasma levels of lactate dehydrogenase, ferritin and neurone-specific enolase, and MYCN status correlated with outcome. However, multivariate analysis showed that only MYCN status retained prognostic value. CONCLUSIONS: In low-risk stage 3 neuroblastoma, standard-dose chemotherapy is associated with an excellent chance of being cured. Aggressive chemotherapy is effective for high-risk patients, but results are still unsatisfactory. MYCN gene amplification is a prognostic indicator for most, but not all, treatment failures.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Occurrence of beauvericin and enniatins in wheat affected by Fusarium avenaceum head blight.

We evaluated Fusarium contamination and the levels of hexadepsipeptide mycotoxins in 13 wheat samples affected by head blight in Finland. Fusarium avenaceum was the dominant species (91%) isolated from all samples, but isolates of F. culmorum (4%), F. tricinctum (3%), and F. poae (2%) also were recovered. Beauvericin (0.64 to 3.5 microg/g) was detected in all 13 samples. Enniatin B (trace to 4.8 microg/g) was detected in 12 samples, enniatin B(1) (trace to 1.9 microg/g) was detected in 8 samples, and enniatin A(1) (trace to 6.9 microg/g) was detected in 10 samples. Ten of 13 strains of F. avenaceum and 2 strains of F. poae and F. tricinctum produced beauvericin in culture on rice (trace to 70, 9.4, and 33 microg/g, respectively). All strains also produced enniatins (trace to 2,700 microg/g). This is the first report on the natural co-occurence of beauvericin and enniatins in wheat infected predominantly by F. avenaceum.

Anti-Bacterial Agents↗
PubMed2001

High incidence and increasing prevalence of MS in Enna (Sicily), southern Italy.

Twenty years after a first survey, a follow-up study was performed on the prevalence of MS in Enna (Sicily), southern Italy. The prevalence of definite MS rose from 53 to 120.2 per 100,000 population. The incidence of definite MS for the period 1986 to 1995 was 5.7 per 100,000 per year. The innermost part of Sicily shows an elevated prevalence of MS, second only to Sardinia in the Mediterranean area.

Adolescent↗
PubMed2001

Splenectomy influences bone marrow infiltration in patients with splenic marginal zone cell lymphoma with or without villous lymphocytes.

BACKGROUND: Splenic marginal zone cell lymphoma (SMZL) is a low grade B-cell lymphoma in which patients can have circulating villous lymphocytes and can show a peculiar intrasinusoidal bone marrow (BM) infiltration. Splenectomy is the reported treatment of choice for these patients. The objective of this study was to evaluate the effects of splenectomy on patients with BM lymphomatous infiltration. METHODS: BM biopsies of 16 patients with SMZL were studied morphologically and immunohistochemically. In 12 patients, BM biopsies were taken before and after splenectomy. Four patients did not undergo splenectomy, and their BM biopsies were performed with an approximately 1 year interval. RESULTS: BM infiltration ranged from 10% to 40% of overall cellularity and was mostly of the intrasinusoidal type. After splenectomy, BM infiltration tended to become frankly nodular and showed an increase in tumor burden. Nonsplenectomized patients showed an unmodified picture. CONCLUSIONS: Splenectomy seems to induce important changes in patients with BM infiltration, probably through the lack of microenvironmental factors on circulating cells. These effects suggest reconsidering the role of splenectomy in the treatment of patients with SMZL.

Adult↗