GABA-induced inactivation of functionally characterized sites in cat visual cortex (area 18): effects on orientation tuning.

Microiontophoresis of the inhibitory transmitter GABA was used to reversibly inactivate small sites of defined orientation specificity at a horizontal distance of some 600 microns from single cells recorded in area 18 of cat visual cortex, and the effects on orientation tuning were studied. The receptive fields of cells at the recording and inactivation sites overlapped extensively. During the inactivation of sites where the orientation preference differed by 45 degrees or more from that of a recorded cell ("cross-orientation" sites), 65% of 54 cells tested showed significant broadening of orientation tuning, with a mean increase in tuning width (measured at half the maximum response) of 93%, and an almost fourfold increase in the relative response to the orientation orthogonal to the optimum, compared with the response to the optimum; four cells essentially lost their orientation tuning. Broadening of tuning reflected an increase in response to nonoptimal orientations and was reversible upon termination of GABA application. The effects on orientation tuning typically peaked within 10-15 min of the onset of GABA iontophoresis with 50-100 nA ejecting currents, and could not be replicated by inactivating sites where the orientation preference was similar to that of a recorded cell; when the orientation preference at the inactivation sites was within 22.5 degrees of that of a recorded cell ("iso-orientation" sites), only 3 of 22 cells showed significant broadening of tuning, and in these cases, the effects were relatively weak (mean increase in tuning width of 39% and a negligible change in the relative response to the orientation orthogonal to the optimum). The effect of inactivating "iso-orientation" sites consisted primarily in an increase in response magnitude. The difference in the magnitude of the effects on orientation tuning elicited by inactivating "cross-orientation" and "iso-orientation" sites was highly statistically significant. Additionally, inactivation of "cross-orientation" or "iso-orientation" sites elicited differential effects on orientation tuning in 10 of the 13 cells in which direct comparisons were made. It is argued that the observed broadening of tuning was due to the loss of a "cross-orientation" inhibitory input, which normally sharpens orientation tuning by suppressing responses to nonoptimal orientations.     

Contribution of neo-electroencephalography in adult functional and psychiatric disorders]

Two comparative studies of the basic activity at rest, with closed eyes taken in conventional EEG and analysed in Neo-EEG are carried out in adults showing functional or psychiatric disorders. The first open study involves 18 subjects suffering from a affection called "neurodystony" and 24 depressed subjects. The second study made in double-blind compares the results of the conventional EEG with the Neo-EEG in 19 depressed patients, 28 alcoholic patients and 26 psychotic patients. The Neo-EEG discloses abnormalities in about 60% of the cases when the conventional EEG is normal. The conventional EEG as well as the Neo-EEG diagnose a greater number of low voltage in alcoholic subjects and clear abnormalities in psychotic subjects. Low voltage is never detected in psychotic patients. In depressives, the Neo-EEG shows about 65% of abnormalities of which an asymmetry of the basic frequency in the center of the two hemispheres when they are analysed separately. That asymmetry develops in parallel with the clinical state. The asymmetry is also found in psychotic patients. In nervous or neurodystonic subjects, the Neo-EEG only discloses 25% of abnormalities. The Neo-EEG appears as an easy method, able to detect dysfunctions which cannot be disclosed with the conventional EEG and useful to follow their developments. Moreover, the result of this technique brings to the fore abnormalities not detected with the conventional EEG: this eventually leads to prescribe other therapies than those initially considered.     

Anticytoplasmic autoantibodies in the diagnosis and follow-up of Wegener's granulomatosis

Sixty-five patients with biopsy-proven Wegener's granulomatosis (WG), 54 with systemic vasculitis, 22 with relapsing polychondritis, 20 with sarcoidosis, 20 with malignant pulmonary lesions, and 15 with other conditions underwent determination of anticytoplasmic autoantibodies (ACPA) by the indirect immunofluorescence technique on neutrophil cytospin preparations to assess the specificity of ACPA for WG, their sensitivity in relationship to the extent and activity of the disease, and their value for follow-up of WG. Of these 65 patients with WG, 38 were ACPA positive. Two patients in the vasculitis group, best categorized as having microscopic polyarteritis, were ACPA positive. We obtained 125 serum samples from the 65 patients with WG and assigned them to one of two categories (limited or generalized), based on the extent of disease. Each of these categories was then subdivided into "active" or "in remission." Median ACPA titers were significantly different between active disease and remission in each category, as well as between active limited and active generalized disease. All patients whose disease changed from active to in remission had reductions in ACPA titer levels; those who experienced flares had titer increases. Patients with intercurrent illnesses or complications of treatment, mimicking WG flares, did not have titer increases. We conclude that ACPA determined by the indirect immunofluorescence technique is highly specific for WG. The sensitivity is dependent on the extent and activity of WG, and serial titer determinations are valuable in monitoring disease activity.     

Psychotherapie und ihre Wirksamkeit bei chronischen Schmerzzuständen

The gate control theory resulted in intensified consideration and investigation of psychological factors in the pathogenesis and continuation of chronic pain. This had led to an increasing interest in the efficacy of psychotherapy for such patients. The different forms of psychotherapy (hypnosis, relaxation, behavior therapy, psychodynamically oriented therapy) currently most often applied are reviewed with notes on the methods and the efficacy recorded for each. The psychodynamically oriented approach has most often been omitted from previous reviews but is integrated in this paper. Four psychodynamic mechanisms are differentiated: the narcissistic mechanism ("psychoprothetic function" of pain), the conversion mechanism ("symbolic function" of pain), the psychovegetative tension mechanism (pain as equivalent of emotion) and the learning mechanism (secondary gain from pain). Generally speaking, a good level of efficacy was ascertained for each form of psychotherapy considered. Hypnosis and relaxation can reduce depression and the perception of pain. Operant programs reduce medication intake and increase the level of activity. Cognitive behavioral strategies are aimed at changing the pain patient's fixation on the body. Psychodynamic approaches concentrate on biographical factors and communication with significant others before the onset of pain reflected in the therapist-patient relationship. However, the value of the results is restricted by the lack of information on patient selection in nearly all the studies considered. The small numbers of patients evaluated in most of the studies suggest that the population investigated may well not be representative, especially if the difficulty of motivating chronic pain patients to present for psychotherapy is taken into account. In addition, a diagnostic classification of the population investigated is lacking. Conclusions are drawn for the planning of future therapy studies.     

Vector electrocardiographic features in patients with hypertrophic cardiomyopathy

The examination indicated that abnormal Q and QS waves recorded along the azes Z and Y in the adjusted lead system far clearly reflected a predominant site of suspected focal and scarring lestoh in hypertrophic cardiomyopathy (HCM) as in coronary heart disease (CHD) (the anterior site in the Z lead and inferior one, in the Y lead), however, the difference in their quantitative characteristics do not fulfil the goals of the electrocardiographic differentiation between HCM and CHD. To differentiate HCM and CHD in the presence of Q and QS waves, a characteristic complex of signs was identified: elevated waves Rx (greater than or equal to 17.5 mm), Sy (greater than or equal to 7.3 mm) of the total value, sigma Rxyz + sigma Sxyz (greater than or equal to 48.3 mm) at the anterior site of "scarring" myocardial lesion and increased waves Sz (greater than or equal to 20.4 mm), sigma Sxyz (greater than or equal to 21.4 mm) at the inferior site. Only "indirect" signs remained on VECG in the presence of scarring myocardial lesion concurrent with arterial hypertension in CHD patients.     

Reproduction of surface and detail of a newly developed cobalt-basis alloy. Influence of preheat temperature

Under improvement of technology of the cobalt-base-alloy "Gisadent KCM 83", the influence of different mould temperatures to the alloy surface was inquired with help of comparism. In spite of best surface at mould temperatures up to 700 degrees C, the influence of higher temperatures to the quality of removable partial dentures isn't important for clinical.     

Routine 18F-2-deoxy-2-fluoro-D-glucose (18F-FDG) myocardial tomography using a normal large field of view gamma-camera

There is a recent need to study glucose metabolism of the heart in ischemic, as well as in "hibernating or stunned" myocardium, and compare it with that in perfusion studies. In non-positron emission tomography centers, positron imaging is possible with a standard Anger-type camera if proper collimation and adequate shielding of the camera crystal can be achieved. For the study with fast-decaying isotopes, seven-pinhole tomography (7PHT), a limited-angle method designed for transaxial tomography of the left ventricle using a nonrotating camera, is well suited, because projections are acquired simultaneously. Individual adjustment (patient supine) of the camera's view axis (CAx) with the left ventricular axis (LVAx) gives excellent results: sensitivity for CHD 82%, specificity 72% in a prospective 201TI study (48 patients, x-ray coronarography as reference). Good alignment of CAx with LVAx is also achieved with the patient prone in LAO in a hammock above the camera surface. In this setting additional lead shielding of the camera is possible using a table reinforced with 5 cm of lead with a central hole for the 7PH-collimator, which has a special lead inlay. This allows utilization of the 511 KeV emitter 18F-FDG, which with a half-life of 109 minutes, can be transported a reasonable distance from the production site. System sensitivity and resolution for 18F was found comparable to 201Tl, 99mTc, and 123I using a phantom. First clinical examinations after 201Tl stress/redistribution studies showed increased 18F-FDG uptake in ischemic heart segments, as well as in "hibernating" nonperfused or "stunned" myocardium.     

Myocardial scintigraphy using 99m-technetium pyrophosphate in the diagnosis of acute myocardial infarct. Comparison of planar and tomographic imaging

The aim of the study was to compare the effectiveness of planar and single photon emission computed tomography (SPECT) imaging with 99mTc-pyrophosphate in the verification of acute myocardial infarction. The study was performed on 39 patients (26 males, 13 females) aged between 41-76 years (mean 61 +/- 9) admitted to CCU for acute myocardial infarction. Patients underwent planar and SPECT imaging using a double-head-camera with a 360 degrees rotation arc within 6 days of admission. Planar images were obtained in three standard projections (anterior, LAO 45 degrees, LAO 75 degrees) with acquisitions of 500000 counts each. To obtain SPECT images ninety projections, each lasting 20 seconds, were taken; subsequently images reconstruction was performed using an iterative algorithm. Positive planar images were found in 21 out of 39 patients; SPECT images were positive in 33 patients. In "Q wave" myocardial infarctions planar images were positive in 13 out of 15 patients, whereas SPECT images were positive in all subjects; in "non-Q wave" myocardial infarctions planar images were positive in 6 out of 22 patients whereas SPECT images were positive in 16 patients (p less than 0.005); in 2 patients with left bundle branch block both planar and SPECT images were positive. A bidimensional echocardiogram was carried out on 38 patients: an alteration of left ventricular regional wall motion was present in 30 subjects; in one patient diffuse hypokinesia was present.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinico-developmental aspects in 44 cases of polymyositis/dermatomyositis

A retrospective study, paying particular attention to the clinical and evolutive aspects of the disease, was performed on 44 subjects affected by polymyositis/dermatomyositis (PM/DM) and hospitalized at the Institute of Medical Clinics of the 1st School of Medicine of Naples University. On the basis of the different clinical pictures, the cases were classified into the following groups: primary PM (4); primary DM (19); DM/PM associated with malignancy (6); childhood DM/PM (3); PM/DM associated with connective tissue disorders (12). Diagnosis was established in terms of the following criteria: a) symmetrical and mostly proximal bilateral muscle weakness (100%); b) elevation of serum enzymes (86.3%); c) electromyographic findings of myopathy sometimes with fibrillation potentials, increased insertional irritability and pseudo-myotonic discharges (93.1%); d) muscle biopsy changes compatible with a clinical form of polymyositis (83.3% out of 30 cases); e) dermatological manifestations including particularly pink or lilac edema-erythema over the periorbital areas, wine-red maculae, Gottron's sign, "poikiloderma vasculare atrophicans", telangiectasias and skin vasculitis (86.3%). An involvement of the extraneural apparatus and organs was present in 40 patients; the most damaged was the osteoarticular apparatus, followed by esophagus, lung, heart and kidney; such pathology was rarely present in the childhood form. A follow-up of the disease has been performed in 36 cases and the therapy consisted fundamentally of high dose corticosteroids (mostly prednisone), associated, in a minority of cases, with methotrexate. A clinical improvement was observed in most cases and a remission of the disease in part of the latter. However, a worsening of the illness was noticed only in the patients suffering from PM/DM associated with malignancy, and mortality rate was 11.1% in all.     

99mTc-labelling of leucocytes with 99mTc-DPO: a complex developed for myocardial imaging

The lipophilic ^99mTc-DPO complex, developed as a myocardial imaging radiopharmaceutical, was used to label leucocytes. After an incubation of 0.1 ml ^99mTc-DPO (8 g DMPE*2HCl) with mixed leucocytes in plasma, the labelling efficiency was over 70%. During incubation in 5 ml plasma, a loss of activity was found between 20% (1 h) and 35% (3 h) caused by elution. Disturbances of cell viability could not be found with the help of the chemiluminescence test. The in vivo recovery was determined in three dogs and was 45%–50% (0.5 h), 30%–36% (1 h), and 18%–24% (3 h). Autologous ^99mTc-DPO-leucocytes were used on seven patients with suspected osteomyelitis, there were four true negative and three true positive results. The target/nontarget ratio determined by ROI in the positive cases was 1.8 to 2.5 at 3 h after injection.