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Biomedical subjects

A Bosco

Publications and source records attributed to A Bosco.

At least 19 recordsLinked to original sources
PubMed2003

(2+1)-dimensional soliton formation in photorefractive Bi12SiO20 crystals.

(2+1)-dimensional spatial solitons in Bi12SiO20 (BSO) photorefractive crystals with large optical activity are experimentally demonstrated. The soliton formation when a Gaussian beam is injected at the input has been previously analyzed numerically and then experimentally investigated. We demonstrate analytically, numerically, and experimentally that by applying static electric biases of high values, the polarization rotation accelerates: this acceleration prevents the beam from broadening if the polarization rotation period becomes shorter than the diffraction length. Contemporary to this nonlinear optical activity, an induced birefringence affects the beam polarization state. Analysis of the polarization dynamics shows that the polarization changes nonuniformly across the beam (with a field dependent speed) until about 30-35 kV/cm; above this limit, the whole beam has just one polarization state. Representation on the Poincaré sphere of the polarization dynamics reveals the existence of a stable polarization trajectory closed around a polarization attractor that depends on the linear optical activity and on the photorefractive nonlinearity. The experimental soliton is well described by the analytical solutions already obtained [Fazio et al., Phys. Rev. E 66, 016605 (2002)].

Journal Article↗
PubMed2003

Correlation of sexual dysfunction and brain magnetic resonance imaging in multiple sclerosis.

Sixty-two patients (40 women and 22 men) with multiple sclerosis (MS) were examined with 1.5 tesla magnetic resonance imaging (MRI) of the brain. Information on sexual and sphincteric disturbances has been collected, and data on disability, independence, cognitive performances and psychological functioning have been assessed. Calculations of T1- and T2-lesion load (LL) of total brain, frontal lobes and pons have been performed using a reproducible semiautomated technique. Whole brain, frontal and pontine atrophies were estimated using a normalized measure, the brain parenchymal fraction (BPF), obtained with a computerized interactive program. When comparing patients with and without sexual dysfunction (SD), there were no differences in total brain, frontal and pontine T1- and T2-LL, as well as in measures of whole brain and frontal atrophy. The only significant difference was in the pontine BPF (P = 0.026). In linear multiple regression analysis, SD was associated with depression (R = 0.56, P < 0.001) and, after adjusting for depression and anxiety, with bladder dysfunction (R = 0.43, P = 0.003) and pontine BPF (R = 0.56, P < 0.001). No association between SD and any of the measures of T1- and T2-LL was found. The findings showed a relationship between SD and pontine atrophy, confirmed the correlation of SD with bladder dysfunction and highlighted the role of psychological factors in determining SD.

Adult↗
PubMed2001

Regulation of dendritic cell recruitment into resting and inflamed airway epithelium: use of alternative chemokine receptors as a function of inducing stimulus.

Dendritic cells (DC) were purified by flow cytometry from rat tracheal mucosa; they exhibited the phenotypic characteristics of immature DC including high endocytic activity, low CD80/86 expression, and in vitro responsiveness to a broad range of CC chemokines. Daily treatment of adult rats with the selective CCR1 and CCR5 antagonist Met-RANTES reduced baseline numbers of tracheal intraepithelial DC by 50-60%, and pretreatment of animals with Met-RANTES before inhalation of aerosol containing heat-killed bacteria abolished the rapid DC influx into the epithelium that occurred in untreated controls, implicating CCR1 and CCR5 and their ligands in recruitment of immature DC precursors into resting airway tissues and during acute bacterial-induced inflammation. Comparable levels of DC recruitment were observed during airway mucosal Sendai virus infection and after aerosol challenge of sensitized animals with the soluble recall Ag OVA. However, Met-RANTES did not affect these latter responses, indicating the use of alternative chemokine receptors/ligands for DC recruitment, or possibly attraction of different DC subsets, depending on the nature of the eliciting stimulus.

Administration, Inhalation↗
PubMed2001

Latex symptoms and sensitisation in health care workers.

BACKGROUND: Natural rubber latex has become an important occupational health concern, particularly among health care workers, who for protection are required to wear latex gloves when at work. This study evaluated the prevalence of latex-related symptoms and sensitisation among a large group of health care workers in Trieste hospitals. METHODS: We evaluated the prevalence of latex-related symptoms in 1,165 health care workers, by means of a questionnaire, a medical examination, skin prick tests and IgE-specific evaluation. We determined atopy and latex sensitivity by skin prick tests using a battery of common inhalant allergens, a commercial latex extract (Lofarma Allergeni, Milan) and individual skin puncture tests for each of the vegetables immunologically related to latex (potato, tomato, chestnut, banana, kiwi fruit). Associations between potential risk factors for latex allergy were assessed. RESULTS: Glove-related symptoms were noticed on 17.2% of the nurses (200) the majority of symptoms being mild dermatitis with itching and erythema (120 subjects, 11.1%). Symptoms suggestive of IgE-mediated latex allergy were found in 51 subjects: 35 (3%) complained of contact urticaria and 16 (2.2%) complained of asthma and/or rhinitis. The resulting symptoms were significantly related to skin prick tests that were positive to latex (odds ratio (OR) = 11.89; 6.40-22.2), to personal atopy (OR = 2.15; 1.47-3.12), to familiar atopy (OR = 2.12; 1.48-3.03), to skin prick test positivity to related fruit (OR = 2.01; 1.16-3.46) but not to prick test positivity to common inhalant allergens (OR = 1.00; 0.71-1.39). Symptoms increased as a direct function of the time-usage of latex gloves and were more prevalent in operating room staff. CONCLUSION: In this large cross-sectional study, glove-related symptoms and latex skin sensitisation appear to be substantial among health care workers, and are related to common signs of atopy. We stress the need of preventive measures to avoid latex exposure when health care workers are at risk of developing allergy symptoms.

Adult↗
PubMed2000

Efficacy of octreotide and sclerotherapy in the treatment of acute variceal bleeding in cirrhotic patients. A prospective, multicentric, and randomized clinical trial.

BACKGROUND: Sclerotherapy is the most widely used method for treatment of acute variceal bleeding. Previous reports have suggested that octreotide infusion is as effective as sclerotherapy. Our aim was to investigate the efficacy and safety of octreotide in comparison with sclerotherapy in controlling variceal bleeding. METHODS: Seventy-six cirrhotic patients were randomized to receive either sclerotherapy (n = 37) or octreotide (n = 39) infusion of 50 microg/h intravenously for 48 h after a bolus of 100 microg, followed by subcutaneous injection of 100 microg/8 h for an additional 72 h. RESULTS: The two groups were similar in base-line data. A similar initial control of bleeding was obtained in 94.6% for sclerotherapy and 84.6% for octreotide (NS). No difference was observed between sclerotherapy and octreotide in rebleeding (23% versus 33%) and treatment failure (22% versus 36%, respectively). Furthermore, the overall success of treatment was 78% for sclerotherapy and 64% for octreotide. No significant difference in mortality was observed between treatments (eight patients for octreotide and three patients for sclerotherapy, NS). CONCLUSIONS: These results show that both treatments present a very high and similar initial and final control of bleeding. However, there is a trend that could be clinically important towards better results in the patients treated with sclerotherapy.

Acute Disease↗
PubMed2000

Orbital abscess: management and outcome.

PURPOSE: To discuss the diagnosis, management and outcome of various types of orbital abscess. METHODS: The medical records of 13 patients diagnosed and treated for orbital abscess were reviewed. The sources of infection included: paranasal sinusitis (n = 5), odontogenic origin of infection (n = 4), one each, temporal fossa abscess, palatal abscess, furuncle on the nose, and secondary to retrobulbar injection of steroid. Computed tomographic scans revealed the presence of an abscess in all 13 cases. Associated findings on CT scan included: sinus disease (n = 8), cavernous sinus thrombosis (n = 2) and subdural empyema (n = 2). All patients were treated with intensive, multiple, intravenous antibiotics and early surgical drainage. RESULTS: Purulent material collected surgically from the orbit cultured Staphylococcus aureus (n = 3), two each Pseudomonas aeruginosa, Proteus mirabilis, Acinetobacter species and one each beta-haemolytic Streptococci, Citrobacter frundi and Enterobacter. Final visual acuity was good in 6 patients (6/12-6/6) and no light perception in 6 others. Visual acuity could not be recorded in the infant. The other complications were intracranial abscess (n = 4), cavernous sinus thrombosis (n = 2) and restricted ocular motility (n = 1). CONCLUSIONS: A high index of suspicion is necessary, along with early institution of appropriate diagnostic imaging, and aggressive medical and surgical treatment for a favourable outcome in cases of orbital abscess.

Abscess↗
PubMed1999

BDNF and NT-4 differentially modulate neurite outgrowth in developing retinal ganglion cells.

We show here that neurite outgrowth of ganglion cells (RGCs) was selectively enhanced following treatment with BDNF or NT-4 in short-term cultures of dissociated cells derived from the neuroretina of postnatal rats. NT-4 was more effective than BDNF. The effect of NT-3 was variable, whereas NGF and CNTF had no effects upon neurite elongation. The neuritogenic responses of RGCs to both BDNF and NT-4 were prevented by competition with soluble TrkB receptor, and abolished by K252a, a selective inhibitor of the tyrosine kinase activity of Trks. These results indicate that the differentiating effects of BDNF and NT-4 are mediated by TrkB receptors, naturally expressed by RGCs. Developing RGCs treated with these TrkB ligands displayed distinct, albeit partially overlapping, patterns of neurite morphology. BDNF supported predominantly polarized outgrowth, whereas NT-4 induced the appearance of intensely branched symmetrical arbors. The lack of RGCs showing combined morphologies (e.g., highly arborized unipolar cells) suggests distinct mechanisms underlying either elongation or branching, and implicates distinct responses of RGC subsets. We conclude that neurite growth in vitro is extensively promoted by neurotrophins in developing RGCs. Moreover, highly homologous neurotrophins such as BDNF and NT-4, presumably activating via TrkB receptors, selectively control the differentiation of distinct ganglion cell neuritic morphologies.

Animals↗
PubMed1999

Sexual dysfunction in multiple sclerosis: a case-control study. I. Frequency and comparison of groups.

Sexual dysfunction is a very important but often overlooked symptom of multiple sclerosis. To investigate the type and frequency of symptoms of sexual dysfunction in patients suffering from multiple sclerosis, we performed a case-control study comparing 108 unselected patients with definite multiple sclerosis, 97 patients with chronic disease and 110 healthy individuals with regard to sexual function, sphincteric function, physical disorders impeding sexual activity and the impact of sexual dysfunction on social life. Information has been collected from a face-to-face structured interview performed by a doctor of the same gender as the patient. The disability, the cognitive performances, the psychiatric conditions and the psychological profile of patients and controls have been assessed. Sexual dysfunction was present in 73.1% of cases, in 39.2% of chronic disease controls and in 12.7% of healthy controls (P<0.0001). Male cases reported symptoms of sexual dysfunction more frequently than female cases (P<0.002). Symptoms of sexual dysfunction more commonly reported in patients with multiple sclerosis were anorgasmia or hyporgasmia (37.1%), decreased vaginal lubrication (35.7%) and reduced libido (31.4%) in women, and impotence or erectile dysfunction (63.2%), ejaculatory dysfunction and/or orgasmic dysfunction (50%) and reduced libido (39.5%) in men. Seventy-five per cent of cases, 51.5% of chronic disease controls and 28.2% of healthy controls (P<0.0001) experienced symptoms of sphincteric dysfunction. In conclusion, a substantial part of our sample of patients with multiple sclerosis reported symptoms of sexual and sphincteric dysfunction. Both sexual and sphincteric dysfunction were significantly more common in patients with multiple sclerosis than in either control group. Our findings suggest that a peculiar damage of the structures involved in sexual function is responsible for the dysfunction in patients with multiple sclerosis, but the highly significant lower frequency of symptoms of depression and anxiety in healthy controls may also imply a possible causative role of psychological factors.

Adult↗
PubMed1999

Sexual dysfunction in multiple sclerosis: II. Correlation analysis.

Sexual dysfunction affects a large part of patients suffering from multiple sclerosis, but some aspects of its clinical presentation and aetiology are not clearly defined yet. In an unselected sample of 108 patients with definite multiple sclerosis we investigated the relationship between symptoms of sexual dysfunctioning and sphincteric dysfunction, patients' and disease characteristics, disability and neurological impairment, psychological and cognitive functioning. Sexual dysfunction directly correlated with presence of physical disorders (r=0.37, P=0.0004), low educational level (r=0.32, P<0.002), disability (r=0.31, P<0.003), age at onset of symptoms (r=0.30, P<0.003), sphincteric dysfunction (r=0.30, P<0.003), age (r=0.30, P<0.004), depression (r=0.29, P<0.005), fatigue (r=0.29, P=0.005), cognitive deterioration (r=0.26, P<0.01), primary-progressive course of disease (r=0.25, P<0.02), neurological impairment (r=0.25, P<0.02), marriage (r=0.24, P<0.02), anxiety (r=0. 23, P<0.03), male gender (r=0.22, P=0.03) bladder dysfunction (r=0. 29, P<0.04), and unemployment (r=0.21, P<0.04). Sexual dysfunction correlated inversely with relapsing - remitting course of disease (r=-0.31, P<0.002). No correlation was found between sexual dysfunction and bowel dysfunction, duration of disease, secondary-progressive course of disease, number and frequency of sexual intercourses in the last year, number of partners, number of exacerbations in the last year, number of months since last exacerbation, masturbation, and fertility. In conclusion, the association between sexual dysfunction and sphincteric dysfunction indicates a common aetiology corresponding to the frequent involvement of the spinal cord in multiple sclerosis, but the concomitant correlation between sexual dysfunction and other variables suggests the possible aetiological role of physical, psychological and sociological factors as well.

Adult↗
PubMed1998

Effect of fat distribution on the pharmacokinetics of cortisol in obesity.

OBJECTIVE: Patients with predominantly upper body obesity are at greater risk for developing diabetes mellitus, hyperlipidemia, hypertension, and cardiovascular disease. Little is known about the mechanisms involved in the regulation of regional body distribution. It has been accepted that the accumulation of fat into adipose tissue depends on regional metabolic regulation of adipocytes and that glucocorticoids play a role in this mechanism. The aim of the present study is to investigate how the pharmacokinetics of cortisol correlate to intraabdominal and subcutaneous fat distribution in obese patients. METHODS: A group of 24 obese patients (13 males and 11 females) were submitted to a CT scan for intraabdominal and subcutaneous fat area evaluation. A 30-min cortisol infusion (0.25 mg/kg) was administered and plasma cortisol was measured over 6 hours. RESULTS: Patients with larger intraabdominal fat areas were found to have a higher cortisol clearance than those with lower intraabdominal fat areas. Cortisol clearance (both, absolute and body-weight corrected) showed a statistically significant correlation with intraabdominal fat area, either expressed by waist-hip ratio or obtained by computerized tomography. CONCLUSIONS: These findings indicate a more effective clearance capability for cortisol in patients with central obesity resulting in lowered cortisol plasma levels despite an increased cortisol secretion observed in this patient group.

Abdomen↗
PubMed1998

[Pneumoretroperitoneum due to pneumatosis cystoides intestinalis. An etiopathogenetic and clinico-diagnostic assessment. A clinical case report].

A case of pneumoretroperitoneum which came out to be caused by pneumatosis cystoides intestinalis, after careful and proper diagnostic evaluation, is described. Physiopathology, etiopathogenesis and clinical peculiarities of this infrequent pathology are examined; most useful tests to be performed in diagnostic differential evaluation, and clinical and surgical therapeutic approaches are also described, especially facing rare complications of PCI, such as pneumoperitoneum and pneumoretroperitoneum.

Abdomen, Acute↗
PubMed1997

Relationship between hardiness and risk of burnout in a sample of 92 nurses working in oncology and AIDS wards.

BACKGROUND: The present study tested the hypothesis that particular personality dispositions act as resistance resources in the encounter with stressful life events. METHODS: The sample consisted of 100 student nurses working in critical areas (oncology and AIDS). At the beginning of the 2nd year course subjects were administered the Kobasa Hardiness Scale and at the end of the year the Maslach Burnout Inventory. RESULTS: Higher hardiness levels at the beginning of the course were associated with lower emotional exhaustion and higher personal achievement scores at the end. As predicted, findings show hardiness scores to be predictive of the risk of burnout. CONCLUSIONS: A screening of personality traits could be useful in preventing the risk of burnout in nurses working in critical areas.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Risk factors in obese women, with particular reference to visceral fat component.

Possible associations between increased visceral fat component and serum lipid concentrations, glucose tolerance and insulinaemia (specific radioimmunoassay) were studied as risk factors for cardiovascular disease in 50 adult obese women without known diabetes and 11 lean normal women. Visceral abdominal fat areas were evaluated by computed tomography and "true" insulin concentrations. Diabetes was observed in 6 obese women (12%) and impaired glucose tolerance in 13 (26%). In obese women, visceral fat area correlated significantly with VLDL-cholesterol, triglycerides, and systolic and diastolic blood pressure, whereas subcutaneous area correlated negatively with cholesterol and LDL-cholesterol. Insulinaemia was not increased in visceral obesity nor correlated with other risk factors. An association between increased visceral fat accumulation, dyslipidaemia and increased diastolic blood pressure was observed, but no significant correlations were noted between fasting "true" insulin or insulin response on an oral glucose tolerance test and intra-abdominal fat areas or dyslipidemia. The gender of the patients could have been an important factor in these last observations.

Adipose Tissue↗
PubMed1996

Reactivity of rolandic spikes.

Factors influencing the frequency of rolandic spikes are rarely reported. We examined the influence of movement, tactile stimulation and cognitive test on the discharge rate of rolandic spikes. We studied 35 children with EEG rolandic spikes. Eighteen children had nonfebrile convulsions. Benign childhood epilepsy with centrotemporal spikes was diagnosed in 12 cases. Testing during the EEG included hand and tongue movements, cognitive tasks and tactile stimulation of face and hands. Rolandic spikes were counted by visual analysis in each phase of the test and the frequency expressed as mean number per min. During tongue movements there was a significantly lower discharge rate when compared to previous and subsequent rest phases. For the left hemisphere there was reduction in discharge rate during right hand movements and looking at colored spots but only when compared with the previous rest phase. The reduction in mean number of spikes/min by tongue movements occurred in patients with and without epilepsy. For patients with cerebral lesion the decrease in discharge rate during tongue movements was not significant whereas for those without cerebral lesion a significant reduction was evident. A decrease in the mean number of spikes/min of 50% or more was significantly more frequent among 29 patients without than among 6 patients with cerebral lesion. Our study showed the inhibition of rolandic spikes by tongue movements confirming the hypothesis that the localization of discharges is an important factor in determining its reactivity. The presence or not of cerebral lesion may be an important factor in the degree of reactivity.

Adolescent↗
PubMed1995

AIDS and suicide issues in Spain.

Current suicidality and other characteristics were assessed in 442 HIV-infected patients, independent of clinical stage, who had been referred to the Consultation Liaison Psychiatrist from an Infectious Disease Unit of a General Hospital in Spain. The referrals were made over a period of 7 years (1988-1994). Suicidality was categorized as suicidal thoughts (5 patients), suicidal equivalents (5 patients) and suicidal attempts (17 cases). Of a total of 27 cases, two died as a result of suicide. The number of known suicide deaths was lower than expected. However, these results may show an underestimate due to the difficulty of differentiating between accidental overdose and actual suicidal attempt in intravenous drug-using patients. Health care professionals must be aware of the potential for suicidal thoughts and suicidal behaviours in HIV-positive patients to enable them to provide the necessary support.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Double-blind, placebo-controlled, randomized, crossover trial of high-dose methylprednisolone in patients with chronic progressive form of multiple sclerosis.

A double-blind, placebo-controlled, randomized crossover trial of high-dose methylprednisolone (MP) was performed in 35 patients with a primarily chronic progressive form of multiple sclerosis as defined clinically according to Poser's criteria. At time 0 of every course of treatment (1 g MP administered i.v. daily for 5 days followed by oral prednisone tapering over 4 days, or placebo) and at 10, 30 and 90 days thereafter, each patient underwent psychometric tests and was clinically tested according to Kurtzke's Expanded Disability Status Scale (EDSS). The disability pattern of most patients who were treated with placebo either worsened or did not change. A statistically significant improvement (p < 0.001) of EDSS in MP-treated patients was recorded. The improvement mainly concerned the pyramidal, cerebellar and sensitive disorders; it was already evident at the first clinical follow-up and lasted for 3 months from the beginning of the treatment. No frequent and/or important side effects were detected throughout the trial.

Adult↗
PubMed1995

Estimation of body fat and lean tissue distribution by dual energy X-ray absorptiometry and abdominal body fat evaluation by computed tomography in Cushing's disease.

Body composition determined by dual energy x-ray absorptiometry and the abdominal visceral fat component determined by computed tomographic scanning were examined in women with Cushing's disease and compared with those in obese women with the same anthropometric parameters and those in nonobese women. Patients with Cushing's had no increase in total body fat or the trunk region (android) component, but had a higher intraabdominal fat area compared to the obese subjects. The total lean tissue mass was slightly reduced in Cushing's compared to that in the obese subjects due to a significant decrease in the muscle of the legs and arms; the reduced amounts of fat and lean tissue masses in the arms were the most significant findings in hypercortisolism. The body mineral and bone calcium contents were slightly reduced in Cushing's compared to those in the obese controls. Thus, although obese subjects had more fat and lean tissue and mineral masses than their normal weight counterparts, the Cushing's patients, with the same total fat mass and its components (except in the arms) as obese individuals, present total lean tissue and fractions, including body mineral and bone calcium contents, similar to those in nonobese subjects due to the depletion of the protein depots, as seen in hypercortisolism.

Absorptiometry, Photon↗