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M Belloni

Publications and source records attributed to M Belloni.

At least 19 recordsLinked to original sources
PubMed2000

A simulation study for the design of a control system for the blood concentration process in autotransfusion.

Autotransfusion is the process in which a patient serves as his or her own blood donor; its most important application is the intraoperative blood salvage, in which the blood collected during a surgical operation is filtered, concentrated, washed, and then reinfused. In an automatic autotransfusion device, such as the DIDECO Compact Advanced, red blood cells (RBCs) are separated from the other unwanted components and concentrated by using a rotating bowl and the effect of centrifugal force. An important characteristic of concentrated RBCs is their hematocrit (Hct), i.e., percent RBC volume divided by total blood volume. The aim of this study is to assess the feasibility of a controller, based on the artificial neural network approach, which is able to provide a closed loop control of the hematocrit of the blood in the bowl at the end of the concentration phase. A simulation approach was adopted both for training the network and for assessing its performances. The results obtained are quite satisfactory, since the target Hct was typically reached within a 3% error, and always within 6% in highly challenging situations.

Biomedical Engineering↗
PubMed1999

Distribution and kainate-mediated induction of the DNA mismatch repair protein MSH2 in rat brain.

DNA repair is one of the most essential systems for maintaining the inherited nucleotide sequence of genomic DNA over time. Repair of DNA damage would be particularly important in neurons, because these cells are among the longest-living cells in the body. MSH2 is one of the proteins which are involved in the recognition and repair of a specific type of DNA damage that is characterized by pair mismatches. We studied the distribution of MSH2 in rat brain by immunohistochemical analysis. We found the level of MSH2 expression in rat brain to be clearly heterogeneous. The highest intensity of staining was found in the pyramidal neurons of the hippocampus and in the entorhinal and frontoparietal cortices. Positive cells were observed in the substantia nigra pars compacta, in cerebellar granular and Purkinje cells, and in the motor neurons of the spinal cord. We investigated the possible modulation of MSH2 expression after injection of kainate. Systemic administration of kainate induces various behavioural alterations and a typical pattern of neuropathology, with cell death in the hippocampal pyramidal neurons of the CA3/CA4 fields. Kainate injection also resulted in a marked, dose-dependent increase of MSH2 immunoreactivity in the hippocampal neurons of the CA3/CA4 fields. The effect was specific, since no changes in immunoreactivity were detected in the dentate gyrus nor in other brain areas. In summary, our data suggest that a mismatch DNA repair system, of which MSH2 protein is a representative component, is heterogeneously expressed in the rat brain and specifically induced by an experimental paradigm of excitotoxicity.

Animals↗
PubMed1999

Induction of two DNA mismatch repair proteins, MSH2 and MSH6, in differentiated human neuroblastoma SH-SY5Y cells exposed to doxorubicin.

The MutS homologues MSH2 and MSH6 form a heterodimeric protein complex that is involved in the recognition of base/base mismatches and insertion/deletion loops, as well as some other types of DNA damage. We investigated the expression of these proteins in undifferentiated and retinoic acid-differentiated human neuroblastoma SH-SY5Y cells by immunocytochemistry, western blot analysis, and RT-PCR. Nuclei from undifferentiated SH-SY5Y cells were found to be immunoreactive to anti-MSH2 and anti-MSH6 antibodies. Following differentiation, the cells stop dividing and change morphology to acquire a neuron-like phenotype. Under these conditions, both anti-MSH2 and anti-MSH6 immunoreactivities were still detectable, although the signals were somewhat less intense. When these cells were exposed for 2 h to neurotoxic concentrations of doxorubicin (50 nM), they exhibited a marked and homogeneous increase of both anti-MSH2 and anti-MSH6 immunoreactivities. As revealed by western blot analysis, these effects were associated with increased protein content and were dose-dependent. Using RT-PCR technology, we also found that doxorubicin treatment did not change MSH2 or MSH6 mRNA levels. Our data indicate that human postmitotic, neuron-like cells constitutively express the molecular machinery devoted to recognition of DNA mismatches and that this system is activated by specific treatment leading to cell death. These findings might help clarify the molecular mechanisms underlying various human neurological diseases that are associated with deficiencies in DNA repair and/or a high rate of DNA damage acquisition.

Antibiotics, Antineoplastic↗
PubMed1998

Induction of tumour-suppressor phosphoprotein p53 in the apoptosis of cultured rat cerebellar neurones triggered by excitatory amino acids.

We found that primary cultures of rat cerebellar granule cells, although definitely postmitotic and terminally differentiated, express the tumour-suppressor phosphoprotein p53. In particular, granule cells both expressed significant levels of p53 mRNA and positively reacted to an anti-p53 antibody, from the first day of culturing. During neurone differentiation, p53 mRNA content did not significantly change, at least up to 12 days in vitro, while p53 immunoreactivity increased gradually. p53 expression appeared to be further modulable being upregulated after stimulation of glutamate ionotropic receptors by glutamate or kainate. Although qualitatively similar, p53 induction by glutamate and kainate differed in terms of intensity and time-course. The glutamate increase of p53 immunoreactivity appeared within 30 min after the treatment and lasted for at least 2 h. Kainate-induced increase of p53 immunoreactivity was delayed, becoming apparent within 2 h and lasting for at least 8 h. Both kainate- and glutamate-induced increases of p53 immunoreactivity were prevented by the non-competitive NMDA receptor antagonist MK 801. As shown by the electrophoretic mobility shift analysis, both glutamate and kainate induced increases of p53 DNA binding activity. Blockade of p53 induction by a specific p53 antisense oligonucleotide resulted in a partial reduction of excitotoxicity with a complete inhibition of the excitatory amino acids induced apoptosis. Our data suggest that stimulation of ionotropic glutamate receptors in neurones results in a p53-dependent apoptosis.

Animals↗
PubMed1998

[Carotid endarterectomy in patients with neurological non-side related (NSRS) symptoms].

Out of 970 carotid endarterectomies (CE) performed for high-grade (> 80%) stenosis of the internal carotid artery (ICA) until 1995, 147 patients with neurological non side-related symptoms (NSRS) and without any cardiac, ocular or vestibular significant pathology have been evaluated, analyzing the medium and long-term functional results (mean follow-up 37.6 months) related to the morphological status of the ICA contralateral and the vertebral arteries. NSRS disappeared in 126 pts (85.71%): contralateral ICA was non-stenotic in 32 cases (25.39%), stenotic < 75% in 68 cases (53.96%), stenotic > 75% in 7 cases (5.55%) and occluded in 19 cases (15.09%); vertebral arteries were pathological in only 6 cases (4.75%), among which 4 were on the same side and 2 on the opposite side of CE. NSRS persisted in 20 pts (13.6%): contralateral ICA was non-stenotic in 5 cases (25%), with a stenosis < 75% in 11 cases (55%) and with stenosis > 75% in 4 cases (20%); vertebral obliterative lesions were 3 (15.78%), among which 1 on the same and 2 on the opposite side of CE. No one statistical comparison among the groups of cases obtained on the ground of the status of ICA and vertebral arteries were significant (p always > 0.05 at chi-square analysis). Authors' data confirmed that high grade stenoses of ICA can cause NSRS and that CE--always performed at the aim to prevent major neurological attacks--can relieve also these functional disorders in the most of cases, independently from the status of the contralateral ICA and the vertebral arteries.

Aged↗
PubMed1997

[Conservative therapy in renal carcinoma: follow-up].

Due to the increasing use of sophisticated imaging techniques, up to 30% of diagnosed renal cell carcinoma (RCC) are asymptomatic and diagnosed incidentally. Getting the cue from our personal survey of conservative renal surgery for renal cell carcinoma with a cancer specific survival of 95.5% after a mean follow up of 32.7 months, a review of the literature is illustrated: numerous studies have documented the technical success rate with this approach as well as long term disease free survival, comparable to that obtained by radical nephrectomy, in patients with unilateral, small, low stage tumors and normal opposite kidney. Patient selection is of extreme importance in case of partial resection in the presence of a normal contralateral kidney. The tumor must be < 3-4 cm, solitary, well delineated on CT, without invasion of the perinephric far or pyelocaliceal system (T1 and T2), easily resectable with at least 1 cm of healthy parenchyma. Only well informed patients who agree on a careful follow up after surgery can be candidates for kidney sparing surgery. In case of imperative surgery the follow up must be strict and personified for every single patient. Those patients who underwent a partial nephrectomy in presence of a normal contralateral kidney should be monitored with a conventional follow up monitored in order to detect an eventual local recurrence: 12 monthly ultrasonography and contrast enhanced CT scan alternately every 6 months for the first five years after surgery and then lifelong once a year by echography and/or CT scan.

Adult↗
PubMed1996

Prolonged in vivo gene expression driven by a tyrosine hydroxylase promoter in a defective herpes simplex virus amplicon vector.

A 9.0-kb fragment of the tyrosine hydroxylase (TH) promoter, previously shown to direct tissue-specific expression in transgenic mice, was fused to an Escherichia coli LacZ reporter gene in a defective herpes simplex virus type-1 (HSV-1) amplicon vector (THlac). The HSV immediate early (IE) 4/5 promoter (HSVlac) was used as a control. LacZ gene expression was visualized by X-Gal histochemical and TH immunocytochemical analysis. Two days and 10 weeks after THlac injection into rat caudate nucleus (CN), X-Gal-stained cells were observed in the substantia nigra (SN) and locus ceruleus (LC) ipsilateral to the injection site. These blue cells were TH-positive neurons as evidenced by double labeling with immunocytochemistry. Moreover, the number of X-Gal+, TH+ (double-positive) neurons in the SN increased at 10 weeks as compared to that seen 2 days after THlac injection. In marked contrast, few double-positive nigral neurons were observed either 2 days or 10 weeks after direct injection of THlac into SN. However, neither nigral nor striatal injection of HSVlac resulted in prolonged gene expression. These results suggest that a neuronal, but not a viral, promoter in an HSV vector can produce cell-type-specific, prolonged, and stable gene expression following retrograde transport. In addition, THlac produced infrequent gene expression in TH-negative cells (CN and dorsal to SN) after THlac injection into CN and SN, respectively. Overall, these results suggest that in some in vivo contexts cell-type-preferred expression can be achieved by a cellular promoter in an amplicon vector. Moreover, they underscore the need for the careful and systematic study of neuronal promoters in HSV vectors.

Defective Viruses↗
PubMed1996

Investigation of a Q-fever outbreak in northern Italy.

OBJECTIVES: A study was conducted to evaluate the extent of a Q-fever epidemic through active case finding in the area of Vicenza (north-eastern Italy), and to identify risk factors for Q-fever in this outbreak. METHODS: 1) Descriptive epidemiology; 2) Seroepidemiological survey; 3) Case-control study. 1) Epidemic curve and maps with the location of cases. Identification of the road followed by the flocks of sheep. 2) Cross-sectional study on humans and flocks of sheep tested for anti-Coxiella burnetii antibodies. 3) Cases were defined by the presence of fever > 38 degrees C plus serological confirmation. Controls were 94 apparently healthy individuals attending outpatient facilities for control visits or certification, group-matched by geographical area, age and gender. A standardized questionnaire was administered by trained interviewers. Odds ratio and 95% confidence intervals (CI) were used to evaluate risk factors for Q-fever. RESULTS: A total 58 cases were identified in a 5-month period. Male to female ratio was 2.8:1; mean age was 42 years (range: 20-65 years). Twenty-eight patients (48%) were hospitalized. Fever was accompanied by asthenia (81%), headache (76%), chills (72%), and myalgia and arthralgia (53%); cough was present in 47% of patients. Rx abnormalities were found in 81% of the patients undergoing chest X-ray. Among 111 apparently healthy family members who underwent serological testing, four (3.6%) had antibodies to Coxiella burnetii. Three flocks which passed through the outbreak area between late May and early June were shown to be infected, with prevalence of antibodies ranging between 45 and 53%. The case-control study showed a significant association with exposure to flocks of sheep (Odds ratio = 6.1; 95% CI 2.5, 16.3). Other potential risk factors were not more commonly reported by cases with respect to controls. CONCLUSIONS: Indirect exposure to flocks of sheep was a determinant of this outbreak of Q-fever. This finding suggests that transmission occurred through inhalation of contaminated airborne particles. The importance of control measures should be stressed in areas traversed by flocks of sheep.

Adult↗
PubMed1996

[T1G3 of the bladder: our experience].

From June 1991 to June 1995 we treated 20 patients affected by T1 G3 TCC of the bladder, 18 men and 2 women, with a mean age of 65.1 years (46-71). In 11 patients the disease was monofocal, with diameter of the tumor under 3.5 cms; in 5 patients monofocal with diameter of the tumor over 3.5 cms; in 1 patient multifocal and in 3 patients complex (mono or multifocal associated with CIS). The 11 patients with monofocal disease under 3.5 cms were treated with TUR-B, the other 9 (all males) were submitted to radical cystectomy with OINB diversion as first choice treatment. The mean follow up (all patients) was 3.2 years (6 months-14 years). Out of the patients of the former group only 3 did not show any relapse, the other 8 showed multiple relapses or metachronous tumors: 5 were treated with TUR-B+BCG, 3 were cystectomized. The patients submitted to cystectomy as first choice treatment did not show any progression of the disease after a mean follow-up of 19.8 months.

Aged↗
PubMed1996

[100 orthotopic neobladders in men after cystectomy: a 5-year experience].

Urethral bladder substitution is traditionally suggested to good prognosis cystectomized patients. In our series this diversion was chosen for all but the salvage cystectomized men. Between the 1st of February 1991 and the 30th of April 1996, one hundred consecutive men underwent lower urinary tract reconstruction after radical cystoprostatectomy for bladder cancer. An orthotopic ileal neobladder was constructed (in 84 cases according to Kock's technique and in 16 to Studer's technique). Total early complication rate was 29% (29/100), including one perioperative death due to sepsis (mortality rate 1%). 13 patients required surgery (6 retroperitoneal hematomas, 2 wound dehiscences, 1 urinary fistula, 1 lymphocele, 1 rectal-neobladder fistula, 1 rectal-cutaneous fistula, 1 necrosis of the terminal ureter). The late complication rate was 19% (19/100); in 8 cases reparative surgery was required (1 mechanical ileus, 2 bladder neck stenoses, 3 stenoses of the ureteral anastomosis, 2 laparoceles). Four patients were lost at the follow-up; out of the 96 remaining patients only 85 were evaluable for continence: continence during the day was achieved in a period between there to six months in 78 patients (91.7%); night continence was achieved with planned awakenings in 60 patients (70.5%). Eight patients recovered potency, another 7 had successful intercourses after PGE1 intracavernous injection. Renal function based on creatinine value was mildly impaired in 5/78 evaluable patients (6.4%) (peak creatinine 2.8 mg%). In 29 patients tumour progression was observed (29%): 9 pelvic and 20 metastatic. Among the latter 2 urethral recurrences were observed (2%). Twenty-four patients died for metastatic cancer, one for primitive lung cancer, one patient for postoperative septic shock. Adjuvant chemotherapy was administered in 11 patients without complication with an indwelling catheter in the neobladder to avoid drug reabsorption. Four patients showed complete response (2 are alive after a mean of 12 months), 6 were non responders and 1 had a partial response. In our series the ileal neobladder is a feasible method of urinary diversion when urethral cancer involvement is ruled out. Early and late complications are proportionally decreasing with experience and overall continence is satisfactory. The fate of the neobladder depends on both the technique and patient's compliance. Only educated patients can cope successfully with neobladder diversion without major complications. All the patients operated for non salvage cystectomy deserve to be diverted with a continent urethral bladder substitution.

Adenocarcinoma↗
PubMed1995

Differential expression of fetal and mature tau isoforms in primary cultures of rat cerebellar granule cells during differentiation in vitro.

The molecular mechanism(s) responsible for the differential expression of various tau protein isoforms as well as their functional role in morphogenesis, neurofibrillary tangle formation and neurodegeneration have not been completely clarified. We found that the expression of tau proteins in primary cultures of cerebellar granule cells from neonatal rat brain is a developmentally regulated process affecting tau synthesis at different levels. Changes in tau RNA splicing are clearly demonstrated by PCR data showing the switching on of the mRNA containing four internal repeats by DIV 6 and the switching off of the mRNA containing three internal repeats after DIV 12. The changes in mRNA levels of the different tau isoforms during development in vitro occur in parallel with changes in tau protein expression, both qualitatively and quantitatively, as shown by Western analysis of protein extracts from granule cells at different DIV with an anti-tau polyclonal antibody. Finally, as indicated by MAP2 and tau immunocytochemistry data, the switch in tau protein expression appears to be contemporary with neurite outgrowth and cell differentiation. Our data suggest that a differential expression of various tau proteins parallels the degree of cell maturation.

Animals↗
PubMed1995

Inhibition of glutamate-induced neurotoxicity by a tau antisense oligonucleotide in primary culture of rat cerebellar granule cells.

Short-term exposure of primary cultures of cerebellar granule cells from neonatal rat brain to high concentrations of glutamate resulted in a significant increase of both immunoreactivity to and mRNA levels of tau protein. Time-course experiments revealed the increases of tau immunoreactivity and mRNA levels to be maximal 2 h after the glutamate pulse. To investigate the relationship between newly synthesized tau protein and glutamate-induced neurotoxicity, neurons were preincubated with a specific tau antisense oligonucleotide. This treatment resulted in (i) inhibition of the glutamate-induced increase of tau immunoreactivity and (ii) a decrease in the sensitivity of the neurons to neurotoxic concentrations of glutamate. These data indicate that induction of the cytoskeleton-associated tau protein participates in the cascade of events promoted by glutamate leading to neurodegeneration.

Animals↗
PubMed1995

[Physiopathology of BPH obstruction].

The underlying BPH related mechanisms of outlet obstruction are outlined (modification of the shape of the bladder neck, failure of funnel formation, geometric variations of the urethra, alpha 1 adrenoceptors mediated sympathetic hyperactivity at the level of the lower genito-urinary tract). Bladder voiding dysfunction in response to prostate obstruction is also discussed and correlated to ultrastructural patterns and clinical symptoms. Finally, a pathogenetic mechanism for detrusor overactivity in obstructed bladder is suggested.

Humans↗
PubMed1995

[Alpha blockers, TUS-P and TUR-P in the treatment of benign prostatic hypertrophy. A comparison using multivariate statistical analysis].

To evaluate the effectiveness of Alpha-blockers, TUI-P and TUR-P in the treatment of obstruction due to BPH, 50 patients, never before treated, were considered. Fifteen were treated with alfuzosin chlorhydrate 7.5 mg/day for four months, 15 were submitted to TUI-P and 20 to TUR-P. In all patients linear purr was carried out before treatment and was repeated from 60 to 90 days after intervention in surgical patients and during the fourth month of treatment in patients treated with alfuzosin. The data obtained were analyzed with the T-test both for dependent and independent samples. The results show that Alpha-blocker contain an increase in maximal flow, without decreasing bladder voiding pressures. On the contrary TUI-P and TUR-P, besides the increase in maximal flow obtain a significant reduction of bladder pressures. The conclusions are the following: maximal flow alone is not a sufficient parameter to evaluate the work of the bladder, the entity of the obstruction and the effectiveness of the therapy. The treatment with Alpha-blockers is unable to reduce the obstruction due to BPH. TUI-P and TUR-P realize an effective deobstruction. Under the same deobstructing effect TUR-P assures a better voiding performance by obtaining higher flow values.

Adrenergic alpha-Antagonists↗
PubMed1994

Antisense strategy unravels tau proteins as molecular risk factors for glutamate-induced neurodegeneration.

1. We investigated the possible involvement of tau proteins in the neurotoxic process activated by glutamate using the oligonucleotide antisense strategy. 2. We found that pretreatment of granule cells with an antisense oligonucleotide of the tau gene completely prevented the increase in tau immunoreactivity induced by glutamate. 3. A significant amount of the tau antisense oligonucleotide (about 1 to 2% of total) was taken up by the cells and remained stable in the cells for at least 60 min. A dose-response study revealed that 25 microM tau antisense oligonucleotide was the most efficacious concentration in terms of prevention of glutamate-induced tau immunoreactivity increases, without affecting basal tau expression. Higher concentrations of tau oligonucleotide antisense reduced tau immunoreactivity in control cells. 4. Significantly, the concentration-response curve of glutamate for inducing neuronal death in cells pretreated with tau antisense oligonucleotide showed a shift to the right compared to those obtained in untreated or tau sense oligonucleotide-treated cells. 5. Since inhibition of tau synthesis does not completely prevent but only decreases the neuronal sensitivity to glutamate, it is tempting to speculate that accumulation of tau within the neuron in response to glutamate represents one of the molecular risk factors lowering the safety margin of neurons to excitotoxic-induced injury.

Animals↗
PubMed1993

Deafferentation induces early and delayed differential changes in the pattern of expression of the various guanine nucleotide binding protein mRNAs in rat striatum.

A polymerase chain reaction-derived method was used to identify and quantitate the relative abundance of the different mRNAs encoding various isoforms of the guanine nucleotide regulatory protein Gs, Gi, and Go alpha subunits in the striata of rats unilaterally injected with 6-hydroxydopamine in the substantia nigra. Thirty days after the lesion, the mRNA levels of the G(o) and of the Gi 1 alpha subunits were increased by about 2-3 times, those of the Gi 3 decreased by about 60% and those of Gi 2 and Gs unmodified. The pattern of expression of the G(o) alpha subunits mRNA changed in a time-dependent fashion, being significant 20 days after the lesion. The decrease in Gi 3 alpha subunit mRNA levels was maximum 10 days after the lesion and tended to be reduced in magnitude with time while the changes in Gi 1 alpha subunit mRNA showed a byphasic behaviour being reduced at 10 days and increased at 30 days after the lesion. These data suggest that the expression of the various G protein alpha subunits in the striatum are continuously regulated by factors originating from afferent neurons and surrounding cells.

Animals↗
PubMed1993

Complications of plasma-exchange.

Complications in apheresis affect on the average 40% of treated patients and 10-14% of the procedures. The mortality rate is 1/500 treated patients. The utilization of more complex techniques, central catheters, plasma infusion and even more the superimposition of different factors increase the incidence and gravity of side effects. Very influent are also the underlying pathologies and the clinical conditions; particularly at risk are patients with TTP/HUS and GBS. However, PE represents a relatively safe therapy in which prevention of complications requires a particularly diligent personnel and a careful evaluation of indications.

Blood Component Removal↗