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Biomedical subjects

L Bianchi

Publications and source records attributed to L Bianchi.

At least 451 records · Page 25Linked to original sources
PubMedDate not supplied

Representing spatial information for limb movement: role of area 5 in the monkey.

How is spatial information for limb movement encoded in the brain? Computational and psychophysical studies suggest that beginning hand position, via-points, and target are specified relative to the body to afford a comparison between the sensory (e.g., kinesthetic) reafferences and the commands that generate limb movement. Here we propose that the superior parietal lobule (Brodmann area 5) might represent a substrate for a body-centered positional code. Monkeys made arm movements in different parts of 3D space in a reaction-time task. We found that the activity of area 5 neurons can be related to either the starting point, or the final point, or combinations of the two. Neural activity is monotonically tuned in a body-centered frame of reference, whose coordinates define the azimuth, elevation, and distance of the hand. Each spatial coordinate tends to be encoded in a different subpopulation of neurons. This parcellation could be a neural correlate of the psychophysical observation that these spatial parameters are processed in parallel and largely independent of each other in man.

Animals↗
PubMedDate not supplied

Cortical networks for visual reaching: physiological and anatomical organization of frontal and parietal lobe arm regions.

The functional and structural properties of the dorsolateral frontal lobe and posterior parietal proximal arm representations were studied in macaque monkeys. Physiological mapping of primary motor (MI), dorsal premotor (PMd), and posterior parietal (area 5) cortices was performed in behaving monkeys trained in an instructed-delay reaching task. The parietofrontal corticocortical connectivities of these same areas were subsequently examined anatomically by means of retrograde tracing techniques. Signal-, set-, movement-, and position-related directional neuronal activities were distributed nonuniformly within the task-related areas in both frontal and parietal cortices. Within the frontal lobe, moving caudally from PMd to the MI, the activity that signals for the visuo-spatial events leading to target localization decreased, while the activity more directly linked to movement generation increased. Physiological recordings in the superior parietal lobule revealed a gradient-like distribution of functional properties similar to that observed in the frontal lobe. Signal- and set-related activities were encountered more frequently in the intermediate and ventral part of the medial bank of the intraparietal sulcus (IPS), in area MIP. Movement-and position-related activities were distributed more uniformly within the superior parietal lobule (SPL), in both dorsal area 5 and in MIP. Frontal and parietal regions sharing similar functional properties were preferentially connected through their association pathways. As a result of this study, area MIP, and possibly areas MDP and 7m as well, emerge as the parietal nodes by which visual information may be relayed to the frontal lobe arm region. These parietal and frontal areas, along with their association connections, represent a potential cortical network for visual reaching. The architecture of this network is ideal for coding reaching as the result of a combination between visual and somatic information.

Animals↗
PubMedDate not supplied

Multicenter trial of prophylaxis with clindamycin plus aztreonam or cefotaxime in gynecologic surgery.

A prospective, randomized, multicenter study was conducted on the efficacy and safety of two prophylactic antibiotic regimens in both abdominal and vaginal hysterectomy. Patients received three intravenous doses of clindamycin (900 mg) plus either aztreonam (1 g) or cefotaxime (1 g); the doses were given at the induction of anesthesia and 8 and 16 hours later. A total of 170 patients undergoing abdominal hysterectomy and 142 patients undergoing vaginal hysterectomy completed the trial and were evaluated. Following abdominal hysterectomy infections occurred at the operative site in 1.2% of patients given a regimen including aztreonam and in 4.7% of those given a regimen including cefotaxime; the difference between the two groups was not significant. Neither were significant differences observed in the incidence of fever, the incidence of bacteriuria, the need for postoperative antibiotics, or the duration of postoperative hospitalization, although results were slightly better for patients receiving clindamycin plus aztreonam. Following vaginal hysterectomy, slightly but not significantly better results for the same parameters were obtained in the group given clindamycin plus cefotaxime. Diarrhea was the only adverse reaction attributable to antibiotic treatment and occurred more frequently in patients given cefotaxime. It was concluded that the two regimens were similarly effective and safe in preventing infections following hysterectomy.

Adult↗
PubMedDate not supplied

Cefodizime modulates in vitro tumor necrosis factor-alpha, interleukin-6 and interleukin-8 release from human peripheral monocytes.

Among third-generation cephalosporins, cefodizime (CFDZ) has shown to modulate many functions of the host defense system against infections. The aim of the present study was to assess the in vitro CFDZ-dependent modulation of interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and IL-8 release from lipopolysaccharide (LPS)-stimulated human peripheral mononuclear cells (MNCs). Two other third-generation cephalosporins: ceftriaxone (CFX) and ceftazidime (CFT), were also tested under the same experimental conditions. At concentrations ranging from 200 to 50 micrograms/ml, CFDZ significantly decreased TNF-alpha and IL-6 release from maximally (LPS 1 microgram/ml) stimulated MNCs (42% inhibition of TNF-alpha release with 100 micrograms/ml of CFDZ). On the other hand, CFDZ revealed a marked stimulatory effect on IL-8 release (200 micrograms/ml of CFDZ induced 51.5% enhancement of IL-8 release). On the contrary, both CFX and CFT failed to exert any significant effect on TNF-alpha, IL-6 or IL-8 release.

Cefotaxime↗
PubMedDate not supplied

Immunoassay of neuron-specific enolase (NSE) and serum fragments of cytokeratin 19 (CYFRA 21.1) as tumor markers in small cell lung cancer: clinical evaluation and biological hypothesis.

NSE is a biochemical marker for small cell lung cancer (SCLC) diagnosis and management. CYFRA 21.1 is a newly developed immunoassay to detect the serum fragments of cytokeratin 19 which are also expressed in SCLC with or without neurofilaments. The aim of this study was to evaluate the diagnostic performance and prognostic role of the two markers in SCLC and their contribution to chemotherapy monitoring and patient follow-up. We studied 62 patients with pathologically proven SCLC: 28 with limited disease (LD) and 34 with extensive disease (ED), and 100 patients with non-malignant pulmonary disease. Immunoradiometric assays (IRMA) were employed to test NSE and CYFRA 21.1 in patients and control subjects. For each patient subset results were expressed as median and interquartile distribution range. NSE and CYFRA 21.1 sensitivity was 0.52 (33/62) and 0.56 (35/62), respectively. In the group of patients with LD, NSE and CYFRA 21.1 sensitivity was 0.42 (12/28) and 0.54 (15/28) and in patients with ED, NSE and CYFRA 21.1 were positive in 0.62 (21/34) and 0.59 (20/34) of cases, respectively. Combining the two markers, a sensitivity of 0.78 (22/28) in LD, 0.82 (28/34) in ED and a global sensitivity of 0.80 (50/62) was obtained. Only NSE was significantly linked to the extension of disease (Mann-Whitney U test p = 0.002) while CYFRA 21.1 did not correlate. The analysis of survival and the evaluation of the two markers at diagnosis showed CYFRA 21.1 to be strongly linked to the patients' outcome, independently of both clinical prognostic factors and NSE levels (log rank and Cox's model). The markers' performance during chemotherapy was tested in a group of 33 patients with at least one marker above cut-off. NSE can be considered a reliable marker of tumor mass modifications under chemotherapy, while CYFRA 21.1 expression seems to be relatively independent of tumor volume modifications. An applicable model of biomarkers in SCLC could be the concurrent assay of NSE and CYFRA 21.1 in pre-therapeutic assessment and therapy planning. CYFRA 21.1 does not play an important role during therapy monitoring and follow-up; in these phases NSE alone may be employed.

Antigens, Neoplasm↗
PubMedDate not supplied

Quantitative analysis of the pendulum test: application to multiple sclerosis patients treated with botulinum toxin.

The aim of this study was to develop quantitative analytical methods in the application of the pendulum test to both normal and spastic subjects. The lower leg was released by a torque motor from different starting positions. The resulting changes in the knee angle were fitted by means of a time-varying model. Stiffness and viscosity coefficients were derived for each half-cycle oscillation in both flexion and extension, and for all knee starting positions. This method was applied to the assessment of the effects of Botulinum toxin A (BTX) in progressive multiple sclerosis patients in a follow-up study. About half of the patients showed a significant decrement in stiffness and viscosity coefficients.

Adult↗
PubMedDate not supplied

EEG findings in West syndrome a follow-up of 20 patients.

Clinical and EEG findings of 36 patients with West syndrome (WS) were reported. Twenty patients (7 males, 13 females; mean age 7.4 months at the first EEG examination) were followed for a mean period of 19.3 months. Fifty per cent of the 8 cases with cryptogenic SW showed a full recovery, 2 cases showed persistence of psychomotor retardation or seizures and 2 of both these features. At the end of follow-up period, 92% of the 12 patients with symptomatic WS showed a psychomotor retardation and 75% a persistence of seizures. EEG pattern was a typical hypsarrhythmic one in 11 patients and atypical in the remaining cases. The typical pattern correlated with a better outcome with full recovery in 27.3% compared with 11.1% in the group with atypical EEG. Moreover EEG monitoring was useful for the evaluation of therapeutic response and in the follow-up of the disease, showing a correlation with clinical course, incidence of spasms and outcome.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Morphology of non A-non B hepatitis (HNANB). A study of 104 cases.

A series of 104 liver biopsies from patients with clinical HNANB were classified under code into established histologic groups. Activity and basic features were semiquantitatively assessed using a score system. In 23/104 cases non viral lesions were diagnosed. After breaking the code the remaining 81 hepatic biopsies were ranged into three groups: post-transfusional cases (PT) (n. 20), sporadic cases with clinically documented initial "acute hepatitis" (SP1) (n. 44), sporadic cases without determined onset of disease (SP2) (n. 17). There were no statistically significant features discriminating histologically PT group from SP 1 + 2 group. However, aggressive forms of hepatitis (acute hepatitis with piecemeal necrosis [AVH+PMN] and chronic aggressive hepatitis [CAH]) were more frequent in PT group (11/20 = 55% in PT versus 28/61 = 45.9% in SP 1+2 groups). No statistical significant differences were detected for the scored basic pattern (i.e. acidophilic body type, mononucleosis-like bead file pattern, etc.). Bile duct lesions were observed approximately with the same frequency in PT and SP1 groups. Prevalence of fatty change was striking: 55% in PT group and 54.1% in SP1 group.

Biopsy↗
PubMedDate not supplied

[An evaluation and comparison of the methodology of 2 otophoniatric screenings performed in the 1989-1990 biennium on a sample of 4-year-old children attending nursery schools].

The Pediatric Otophoniatric Department of U.S.L.75II, the Multicenter of Preventive Medicine in Via Cherasco, 5, Milan, carried out two otophoniatric screenings on about 70 four-year-old nursery school children. While this screening was considered experimental in four schools, the ultimate goal is to extend it to all the nursery schools in the same area. The primary aim of the screening was to individualize several pathologies of the upper respiratory tract in this age range. The second aim was to identify language pathologies in children under the age of six in order to treat them as soon as possible with adequate and preventive therapy and appropriate language re-education before their entrance into primary school. The materials and methods employed were as follows: O.R.L. examination: otoscopy, rhinoscopy, oropharyngoscopy, indirect laryngoscopy (after individualization of dysphonia); Audiometric test: peep show in free field with a 250 Hz-4000 Hz frequency range at 30 dB; Language evaluation through examination and interpretation of questionnaires formulated in order to evaluate language development filled in by the children's teachers. Two modifications in the method used in the 1989 study were made in the 1990 screening: The preventive use of an auditory duct cleaner and the distribution of the above-mentioned questionnaires at the very beginning of the study. These two changes improved screening planning as well as development. The results of the two screenings were compared and an increase in the percentage of children examined and subjected to the audiometric test was noted. In fact, in the 1989 study, only 77% of the children underwent the audiometric test (23% had ear wax), while in the 1990 study 100% underwent the test (ear cleaner had been used). With regard to the questionnaires, the data were gathered four months after screening in the 1989 study, whereas in the 1990 study this phase was carried out on the same day of the screening. The new methodology saved time in the screening.

Audiometry↗
PubMedDate not supplied

[Evaluation of the arterial share of portal flow using a scintigraphic technique in patients with liver cirrhosis. Correlations with other parameters of portal hypertension].

This study aimed to measure in semiquantitative terms the arterial-venous ratio of the portal flow using a scintigraphic technique, by means of a simple intravenous injection of a 99mTcDiethylHIDA bolus, a method which was found to be extremely simple and non-invasive, with a good degree of repeatibility. The percentage of arterialisation of the portal flow was found to be higher in cirrhotic patients compared to non-hepatopathic subjects, and among cirrhotic patients it was correlated with the severity of disease, the presence and degree of esophageal varices, and the presence of porto-systemic shunts, assessed using the ammonium chloride test.

Adult↗
PubMedDate not supplied

Acute and short-term effects of nitrendipine and diltiazem at rest and during exercise in hypertensive patients.

The subjects were 30 patients with mild-to-moderate hypertension randomly assigned to receive 10 mg of nitrendipine twice daily or 60 mg of diltiazem thrice daily for 14 days. On days 1 and 14 the patients performed an effort test (to a maximum of 100 W) before and after drug administration. Both nitrendipine and diltiazem reduced systolic and diastolic blood pressure; after 14 days of treatment, the reductions in blood pressure were significantly greater in the nitrendipine-treated patients than in the diltiazem-treated patients. Blood pressures were reduced at maximum effort in both treatment groups before drug administration on day 14 compared with day 1. Two hours after drug administration on days 1 and 14, the reductions in effort blood pressures were significantly greater after nitrendipine than after diltiazem. No side effects were noted in either group. It is concluded that nitrendipine is safe and effective in patients with mild-to-moderate hypertension at rest and during exercise.

Blood Pressure↗
PubMedDate not supplied

[Ciprofloxacin by the intravenous route in the treatment of respiratory infections].

A clinical trial was performed to evaluate the efficacy of ciprofloxacin by iv administration in the treatment of respiratory infections. Twenty-two in-patients affected with acute lower respiratory tract infections, mainly infectious exacerbations of chronic obstructive lung disease (COLD), were treated with ciprofloxacin at the daily dosage of 400 mg iv, in two administrations. Overall clinical results were satisfactory (15 patients cured, 7 patients improved). Concerning bacteriological results, pathogen eradication was achieved in 83.3% of cases. Tolerability was good: no adverse events were observed.

Aged↗
PubMedDate not supplied

Hydatid cyst fistula into the aorta.

A case is presented of fistula formation between a primary hydatid cyst and the abdominal aorta which we believe is the first in the world literature. The patient underwent surgery with a diagnosis of aneurysm of the coeliac trunk. During the operation the presence was discovered of a hydatid cyst opening into the aorta. It was dealt with by partial resection and closing of the communication. Three months later the patient was readmitted with a new bleeding episode which resulted in a fatal outcome.

Aorta, Abdominal↗