Binding by temporal structure in multiple feature domains of an oscillatory neuronal network

An important step in visual processing is the segregation of objects in a visual scene from one another and from the embedding background. According to current theories of visual neuroscience, the different features of a particular object are represented by cells which are spatially distributed across multiple visual areas in the brain. The segregation of an object therefore requires the unique identification and integration of the pertaining cells which have to be "bound" into one assembly coding for the object in question. Several authors have suggested that such a binding of cells could be achieved by the selective synchronization of temporally structured responses of the neurons activated by features of the same stimulus. This concept has recently gained support by the observation of stimulus-dependent oscillatory activity in the visual system of the cat, pigeon and monkey. Furthermore, experimental evidence has been found for the formation and segregation of synchronously active cell assemblies representing different stimuli in the visual field. In this study, we investigate temporally structured activity in networks with single and multiple feature domains. As a first step, we examine the formation and segregation of cell assemblies by synchronizing and desynchronizing connections within a single feature module. We then demonstrate that distributed assemblies can be appropriately bound in a network comprising three modules selective for stimulus disparity, orientation and colour, respectively. In this context, we address the principal problem of segregating assemblies representing spatially overlapping stimuli in a distributed architecture. Using synchronizing as well as desynchronizing mechanisms, our simulations demonstrate that the binding problem can be solved by temporally correlated responses of cells which are distributed across multiple feature modules.

Clinical significance of urinary cyclic guanosine monophosphate in diagnosis of heart failure

We measured concentrations of guanosine 3',5'-monophosphate (cGMP) in plasma and urine of healthy subjects and patients with congestive heart failure, renal impairment, neoplastic disease, and hepatic cirrhosis. There was no correlation between cGMP concentrations in urine and in plasma. In all patients except those with renal impairment, urinary cGMP concentrations were significantly higher than in healthy persons. Only patients with heart failure or renal impairment showed significantly increased plasma cGMP concentrations. In contrast, cGMP in urine does not relate to the clinically assessed severity of heart failure (New York Heart Association functional classes). Determination of cGMP in plasma results in higher sensitivity and specificity for diagnosing heart failure than measurement of cGMP in urine.

[Life-threatening diarrhea in atypical course of legionellosis]

After eating a meal of poultry a 41-year-old man fell ill with severe diarrhoea, persistent high fever of around 39 degrees C, dehydration and somnolence. On admission to hospital physical examination was normal except for signs of dehydration. The blood count showed a leukocytosis (13,300/microliters) with 60% stab-form neutrophils. The erythrocyte sedimentation rate was raised to 49/82 mm. Also increased were the serum concentrations of creatinine (3.5 mg/dl), creatine kinase (179 U/l), lactate dehydrogenase (298 U/l) and C-reactive protein (16.8 mg/dl). Bacteriological and virological examinations of blood and stool were negative. A normal fluid and electrolyte balance was re-established. But as there was no improvement, ampicillin was administered, 2 g three times daily, then ciprofloxacin, 500 mg two times daily, and finally combined with metronidazole, 500 mg three times daily. Despite this treatment a chest radiograph on the tenth day revealed an infiltration in the left basal lung segment, and the legionella titre became positive at 1:2045. The antibiotic treatment was changed to 150 mg roxithromycin two times daily. The fever fell within 3 days and the diarrhoea stopped after 5 days. He was discharged free of symptoms after 24 days.

The X-ray structure of the GCN4-bZIP bound to ATF/CREB site DNA shows the complex depends on DNA flexibility

The X-ray structure of the DNA binding domain of the yeast transcriptional activator protein GCN4 bound to a DNA fragment containing the sequence of the perfectly symmetrical ATF/CREB site has been solved to 3.0 A resolution. The architecture of this specific recognition complex supports the current model for bZIP proteins: a homodimer of parallel alpha-helices form an interhelix coiled-coil region via the leucine zipper, and the two N-terminal basic regions fit into the major groove of half sites on opposite sides of the DNA double helix. The structure shows that DNA flexibility plays the predominant role in the preservation of protein contacts with the symmetric ATF/CREB site (ATGACGTCAT) as compared to the pseudo-symmetric AP-1 target site (ATGACTCAT), overcoming the positional displacement of functional groups introduced by the additional G.C base-pair at the center of the ATF/CREB sequence.

Squint affects synchronization of oscillatory responses in cat visual cortex

As shown previously, neurons in various areas of the cat's visual cortex respond to appropriate visual stimuli with oscillatory activity in the frequency range of 30-70 Hz. It has been suggested that synchronization of such responses serves to define assemblies of coherently active cells which represent individual visual objects. In this study, we have investigated this putative binding mechanism in the visual cortex of strabismic cats. We used six adult cats in which divergent squint had been induced surgically at the age of 3 weeks. Multiunit activity was recorded from area 17 with arrays of four or five closely spaced microelectrodes. Subsequently, auto- and cross-correlation functions were computed for all spike trains. To quantify the oscillatory nature of the responses and the strength of synchronization between spatially remote sites, damped sine wave functions were fitted to the correlograms. Analysis of responses obtained from 202 recording sites showed that the vast majority of cells had become monocular. Auto-correlation analysis revealed that the proportion of oscillatory firing patterns was similar to that observed in normal cats. However, cross-correlation analysis of 153 response pairs demonstrated that synchronization was reduced significantly between cells dominated by different eyes while it was as frequent and strong as in normal cats between cells dominated by the same eye. These findings indicate that strabismus not only causes a reorganization of afferent inputs but also affects intracortical interactions.(ABSTRACT TRUNCATED AT 250 WORDS)

Hereditary complete deficiency of the fourth component of complement: effects on the kidney

Hereditary complete C4 deficiency has until now been detected in 18 patients. A disturbed clearance of immune complexes probably predisposes these individuals to systemic lupus erythematosus and other immune complex diseases. Renal involvement of hereditary complete C4 deficiency is described in seven patients from three families. Three patients of one family suffered from SLE and a severe mesangial and endocapillary proliferative glomerulonephritis which required immunosuppressive treatment. In two patients from a second family a mild focal and segmental mesangioproliferative glomerulonephritis was present which, except for an episode of acute renal failure in one patient, did not cause serious clinical problems. One additional child died without renal involvement. The patient from a third family developed Henoch-Schoenlein purpura, mesangioproliferative glomerulonephritis with segmental scarring and terminal renal failure. Immunofluorescence studies showed deposition of immunoglobulins and complement C3 in the glomeruli. Severity of renal disease is probably determined by activation of the alternative pathway of complement in the kidney.

Elevated plasma concentrations of lipoprotein(a) in patients with end-stage renal disease are not related to the size polymorphism of apolipoprotein(a)

Patients with terminal renal insufficiency suffer from an increased incidence of atherosclerotic diseases. Elevated plasma concentrations of lipoprotein(a) [Lp(a)] have been established as a genetically controlled risk factor for these diseases. Variable alleles at the apo(a) gene locus determine to a large extent the Lp(a) concentration in the general population. In addition, other genetic and nongenetic factors also contribute to the plasma concentrations of Lp(a). We therefore investigated Apo(a) phenotypes and Lp(a) plasma concentrations in a large group of patients with end-stage renal disease (ESRD) and in a control group. Lp(a) concentrations were significantly elevated in ESRD patients (20.1 +/- 20.3 mg/dl) as compared with the controls (12.1 +/- 15.5 mg/dl, P < 0.001). However, no difference was found in apo(a) isoform frequency between the ESRD group and the controls. Interestingly, only patients with large size apo(a) isoforms exhibited two- to fourfold elevated levels of Lp(a), whereas the small-size isoforms had similar concentrations in ESRD patients and controls. Beside elevated Lp(a) concentrations, ESRD patients had lower levels of plasma cholesterol and apolipoprotein B. These results show that elevated Lp(a) plasma levels might significantly contribute to the risk for atherosclerotic diseases in ESRD. They further indicate that nongenetic factors related to renal insufficiency or other genes beside the apo(a) structural gene locus must be responsible for the high Lp(a) levels.

Bone metabolism in children with asthma treated with inhaled beclomethasone dipropionate

Previous studies have shown that inhaled corticosteroids can affect bone metabolism in adults. A study to assess the effect of inhaled beclomethasone, 300 to 800 micrograms/day for at least 6 months (mean 25 months), was therefore undertaken in children. In part 1 of the study, 18 children with asthma, aged 4 to 17 years (mean 10.1 years), were compared with an age- and sex-matched group of children with asthma not treated with corticosteroids. In part 2, eight more pairs were compared. Comparisons were also made with 61 healthy children. Bone mineral density measured by radiographic absorptiometry, and bone mineral content measured by single-photon absorptiometry and by dual-energy x-ray absorptiometry, showed no significant differences. Serum levels of calcium, magnesium, zinc, total alkaline phosphatase, bone specific alkaline phosphatase, parathyroid hormone, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D also showed no differences. The activity of tartrate-resistant acid phosphatase, a marker of bone resorption, was significantly lower in the beclomethasone group than in both the asthma control and the normal control groups, but urine calcium excretion did not differ. Patients with asthma had lower serum osteocalcin and higher serum copper levels than control subjects without asthma, but treatment with beclomethasone did not affect these values. We conclude that inhaled beclomethasone (up to 800 micrograms/day) does not reduce bone mineralization or increase bone resorption. Effects on bone formation were difficult to assess because asthma per se caused a significant reduction in osteocalcin, a sensitive marker of bone formation.

Wegener's granulomatosis and Henoch-Schönlein purpura in a family with hereditary C4 deficiency

Described here is a family in which the father with partial C4 deficiency had Wegener's granulomatosis and a son with complete C4 deficiency presented with Henoch-Schönlein Purpura. The possible role of C4 deficiency in the pathogenesis of both vasculitic disorders is discussed.

[Epidemiology of alcoholism in Voralberg. Comparison of administrative incidence 1967, 1977 and 1987 in a regional psychiatric hospital]

We report on the administrative incidence of alcoholism as registered by admissions for treatment in the regional psychiatric hospital, in Vorarlberg, caring for approximately 330,000 inhabitants. 1967, 1977 and 1987 were chosen as years of observation, thus describing the regional development of alcoholism in the last 20 years. Selected epidemiological data are compared to those of local population. Over the years a vast increase in admissions and treatments was registered--a result of changes in information on the addiction itself and improvement in facilities, staff and medical care in general. Whereas female involvement has sharply risen as compared to earlier decades, it now appears to have studied at a rate of 3:1 (m:f). In 1987 juvenile alcoholism as rated by hospital-admissions had comparatively declined. A greater number of married alcoholics in more qualified positions decided on treatment. Concordant somatic and psychiatric diseases are discussed. The results stress the importance of different approaches to motivation and treatment in this complex phenomenon.

Clinical observations of nebulized flunisolide in infants and young children with asthma and bronchopulmonary dysplasia

Severe bronchopulmonary dysplasia (BPD) is frequently associated with asthma. The combination is often severe enough to necessitate corticosteroid therapy. There are no commercially available nebulizer solutions of corticosteroids for use in infants and young children. Seven infants and small children with very severe BPD and asthma aged 6-24 months, were treated with flunisolide, 187-250 micrograms q.i.d. in the form of nasal spray delivered by nebulizer. After treatment for 2.5-20 months, four patients showed clinical improvement, one initially improved but later deteriorated and died of cardiac failure, and two patients showed no improvement and died within 3 months. The number of days of hospitalization was significantly reduced from 8.4/month to 2.5/month (P less than 0.05). No side-effects were detected and it was felt that the three patients who died, did so as a consequence of very severe BPD and its cardiac consequences. The suspension remained stable for 80 min when mixed with normal saline, cromolyn sodium, albuterol, or acetylcysteine. It is concluded that nebulized flunisolide is a potentially useful treatment for infants and young children with asthma and BPD.

Temporal coding in the visual cortex: new vistas on integration in the nervous system

Although our knowledge of the cellular components of the cortex is accumulating rapidly, we are still largely ignorant about how distributed neuronal activity can be integrated to contribute to unified perception and behaviour. In the visual system, it is still unresolved how responses of feature-detecting neurons can be bound into representations of perceptual objects. Recent crosscorrelation studies show that visual cortical neurons synchronize their responses depending on how coherent features are in the visual field. These results support the hypothesis that temporal correlation of neuronal discharges may serve to bind distributed neuronal activity into unique representations. Furthermore, these studies indicate that neuronal responses with an oscillatory temporal structure may be particularly advantageous as carrier signals for such a temporal coding mechanism. Based on these recent findings, it is suggested here that binding of neuronal activity by a temporal code may provide a solution to the problem of integration in distributed neuronal networks.

Synchronization of oscillatory neuronal responses in cat striate cortex: temporal properties

Previously, we have demonstrated that a subpopulation of visual cortical neurons exhibit oscillatory responses to their preferred stimuli at a frequency near 50 Hz (Gray & Singer, 1989). These responses can selectively synchronize over large distances of cortex in a stimulus-specific manner (Gray et al., 1989; Engel et al., 1990 alpha). Here we report the results of a new analysis which reveals the fine temporal structure inherent in these interactions. We utilized pairs of recordings of the local field potential (LFP) activity from area 17 in the anesthetized cat which met two criteria. The LFP was correlated with the underlying unit activity at each site and the recording sites were at least 5 mm apart in cortex. A moving-window technique was applied to compute cross correlograms on 100-ms epochs of data repeated at intervals of 30 ms for a period of 3 s during each direction of stimulus movement. A statistical test was devised to determine the significance of detected correlations. In this way we were able to determine the magnitude, phase difference, frequency, and duration of correlated oscillations as a function of time. The results demonstrate that (1) the duration of synchrony is variable and lasts from 100-900 ms; (2) the phase differences between and the frequencies of synchronized responses are also variable within and between events and range from +3 to -3 ms and 40-60 Hz, respectively; and (3) multiple correlation events often occur within a single stimulus period. These results demonstrate a high degree of dynamic variability and a rapid onset and offset of synchrony among interacting populations of neurons which is consistent with the requirements of a mechanism for feature integration.

Plasma apolipoprotein A-IV metabolism in patients with chronic renal disease

The plasma concentration and distribution of apolipoprotein A-IV were investigated in normotriglyceridaemic patients with end-stage renal disease and compared with those in a sex- and age-matched control group with normal renal function. A three-fold elevated plasma mean concentration of apolipoprotein A-IV was found in patients with end-stage renal disease treated by haemo- or peritoneal dialysis (58.5 +/- 18.9 mg dl-1 or 50.5 +/- 12.2 mg dl-1, respectively) compared with the controls (18.3 +/- 6.4 mg dl-1). The plasma distribution of apolipoprotein A-IV was studied in patients treated by haemodialysis and in controls by gel permeation chromatography. In the haemodialysis group, 40.3% of the apolipoprotein A-IV was found to be associated with the fraction of high density lipoproteins, whereas the rest (59.7%) was not associated with lipoproteins. This distribution was significantly different from that in the control group (24.8% vs. 75.2%, 0.01 less than P less than 0.05). The elevated plasma concentrations of apolipoprotein A-IV in the patients are not related to triglyceride levels and therefore are unlikely to result from an impaired catabolism of triglyceride-rich lipoproteins. The accumulation of apolipoprotein A-IV in high density lipoproteins from patients with end-stage renal disease might reflect the impaired reversed cholesterol transport mechanisms which are believed to be a major cause of the high prevalence of atherosclerotic diseases in these patients.

Direct physiological evidence for scene segmentation by temporal coding

Theoretical studies have suggested that scene segmentation may be accomplished by a temporal coding mechanism using synchronization of neuronal responses. Here we report a direct experimental test of this hypothesis. Neuronal responses were recorded simultaneously from two to four sites with overlapping receptive fields in cat visual cortex. Correlation analysis revealed that all cells synchronized their responses irrespective of their orientation preference when they were activated by a single light bar. However, when stimulated with two superimposed light bars of different orientations, the same cells segregated into distinct assemblies according to their orientation preferences. Within each of these assemblies responses were synchronized, but correlation was absent between the two assemblies. These results are compatible with the hypothesis that responses to individual objects in a scene are distinguished by synchrony, whereas responses to different objects show no temporal correlation, thus allowing for the segmentation of superimposed stimuli. We conclude that stimulus-specific synchronization of spatially distributed neuronal responses may provide a physiological mechanism for scene segmentation.

Renal expression of intercellular adhesion molecule-1 in different forms of glomerulonephritis

1. Expression of intercellular adhesion molecule-1 was investigated in five normal kidneys and 47 renal biopsies with the use of monoclonal antibody 7F7 and immunoperoxidase staining. 2. In the normal kidney, intercellular adhesion molecule-1 was expressed on endothelial cells of glomerular and peritubular capillaries, on Bowman's capsule, on some interstitial cells and weakly in the mesangium. 3. Increased glomerular staining was detected in early cases of rapidly progressing glomerulonephritis (5/8) and in some cases of non-IgA mesangioproliferative glomerulonephritis (5/9), IgA nephropathy (3/5), Henoch-Schoenlein purpura (2/2), lupus nephritis (5/6) and focal segmental glomerulosclerosis (1/3). A decrease in intercellular adhesion molecule-1 expression was noted in advanced rapidly progressive glomerulonephritis (3/8), two cases of membraneous nephropathy, one severe mesangioproliferative glomerulonephritis biopsy, the two membranoproliferative glomerulonephritis biopsies and in sclerotic loops in focal segmental glomerulosclerosis. 4. Expression de novo on tubular epithelial cells occurred in rapidly progressive glomerulonephritis, in membranoproliferative glomerulonephritis, and to a lesser extent in some cases of membraneous nephropathy, minimal change disease, IgA nephropathy, focal segmental glomerulosclerosis, a severe case of mesangioproliferative glomerulonephritis and in the mixed essential cryoglobulinaemia case. In 63% of positive tubuli, intraluminal cells which expressed CD18, the common beta-chain of leucocyte-function-associated antigen-1, Mac-1 and p150,95, were present. 5. Intercellular adhesion molecule-1 was also found on the majority (59%) of infiltrating mononuclear cells in all forms of glomerulonephritis.

Synchronization of oscillatory neuronal responses between striate and extrastriate visual cortical areas of the cat

Recent studies have shown that neurons in area 17 of cat visual cortex display oscillatory responses which can synchronize across spatially separate orientation columns. Here, we demonstrate that unit responses recorded from the posteromedial lateral suprasylvian area, a visual association area specialized for the analysis of motion, also exhibit an oscillatory temporal structure. Cross-correlation analysis of unit responses reveals that cells in area 17 and the posteromedial lateral suprasylvian area can oscillate synchronously. Moreover, we find that the interareal synchronization is sensitive to features of the visual stimuli, such as spatial continuity and coherence of motion. These results support the hypothesis that synchronous neuronal oscillations may serve to establish relationships between features processed in different areas of visual cortex.

Interhemispheric synchronization of oscillatory neuronal responses in cat visual cortex

Neurons in area 17 of cat visual cortex display oscillatory responses that can synchronize across spatially separate columns in a stimulus-specific way. Response synchronization has now been shown to occur also between neurons in area 17 of the right and left cerebral hemispheres. This synchronization was abolished by section of the corpus callosum. Thus, the response synchronization is mediated by corticocortical connections. These data are compatible with the hypothesis that temporal synchrony of neuronal discharges serves to bind features within and between the visual hemifields.

Renal function after tumor enucleation in a solitary kidney

Whether extensive ablation of renal mass in humans leads to progressive glomerulosclerosis, proteinuria, and hypertension, as it does in animal models, is a matter of controversy. We have studied kidney function in six patients who underwent enucleation of a renal cell carcinoma in a solitary kidney. Four patients had previously had a nephrectomy. The two others each had one atrophic, nonfunctioning kidney. Serum creatinine levels before surgery were within the normal range (mean, 99.9 mumol/L [1.13 mg/dL]). Two weeks after tumor enucleation, creatinine levels were significantly higher than the preoperative values (mean, 124.6 mumol/L [1.41 mg/dL]). The follow-up period varied from 10 to 23 months. In all patients, kidney function improved during the following months. Serum creatinine levels nearly reached preoperative values in all patients (mean, 105.2 mumol/L [1.19 mg/dL]). None of the patients showed a progressive deterioration in renal function or proteinuria. We found a modest increase in blood pressure in two patients who had been normotensive before surgery. In conclusion, tumor enucleation in a solitary kidney did not cause significant renal injury to the remnant kidneys in our patients, at least in the short term.

Bronchial hyperreactivity in children with Marfan syndrome

Marfan syndrome is known to have pulmonary manifestations such as pneumothorax. There have been few previous studies of pulmonary function tests and none of bronchial hyperreactivity. Therefore, pulmonary function tests were performed in 11 children with Marfan syndrome and 11 normal children. Bronchial responsiveness was tested in ten of the Marfan patients by methacholine challenge test and response to bronchodilator. Because of disproportionate length of legs in Marfan patients, an "ideal" standing height was calculated from sitting height. Pulmonary function tests, as absolute values or as percent predicted based on "ideal" height, were not different in Marfan patients and normals, although a few individual patients had abnormal function (mostly airway obstruction and hyperinflation). Response to methacholine challenge was positive on forced expiratory volume in 1 second (FEV1), forced expiratory flow between 25 and 75% VC (FEF25-75%), and FEF50%, in 37.5%, 60%, and 70% of tests respectively. A significant response to bronchodilators was obtained in 40% of patients as measured by FEV1, in 90% by FEF25-75% and in 100% by FEF50%. Pulmonary function tests after bronchodilator were significantly higher when compared with values before the bronchodilator as well as with the baseline before methacholine. Therefore, most if not all patients with Marfan syndrome had hyperreactive airways in this relatively small group of patients. Even though only one patient had a diagnosis of asthma, six more had subtle symptoms. It is concluded that tests for bronchial hyperreactivity could be part of the routine investigation in Marfan syndrome. Further studies on larger numbers of patients are still needed.

Treatment considerations in children aged 0-5 years

Children in the first year of life have a less satisfactory response to treatment, but it is still worthwhile using bronchodilators by oral or nebulized route. In more severe cases, cromolyn or nebulized steroids are needed. Over 1 year, response to therapy is better and metered-dose inhalers with spacers become an easier way to deliver medication, although in severe acute attacks the nebulized route remains the preferred one.

Combined electroconvulsive and neuroleptic therapy in schizophrenia refractory to neuroleptics

The results of treatment in 13 schizophrenic patients (nine males, four females) who underwent electroconvulsive therapy (ECT) because of varying degrees of therapy resistance to neuroleptics (therapy failures, renewed and in some cases catatonic exacerbation under neuroleptic therapy, neuroleptic intolerance) are reported. The single treatments, which were carried out on average 12 times (between six and 20 times), led from very good to good remission in a period of between 10 and 7 years in nine patients. Four patients did not respond adequately: the small improvement of psychopathology on discharge correlated with unfavorable outcome. In three of these patients, the asthenic syndrome was found on admission and persisted. In patients with good remission, neuroleptics could be reduced after ECT by over 70%, and over 50% in patients with poor remission. This result confirms corresponding literature data with regard to neuroleptics. The results in this highly selected group also confirm Bleuler's 'one third rule' of remissions, also the fact that global outcome does not correlate with response to neuroleptics, as well as confirming the relevance of the psychopathological state on discharge as an outcome predictor.

Autoradiographic analysis of binding sites for 125I-Bolton-Hunter-substance P in the human eye

Substance P is known to exert potent effects in peripheral tissues, and is thought to be important for ocular function. The mechanism of action of substance P in the human eye is not known. As a basis for biochemical characterization specific binding of 125I-Bolton-Hunter-substance P was demonstrated in the human eye using autoradiographic methods. Biochemical characterization on slide-mounted tissue preparations showed that binding was saturable with a KD of 0.27 +/- 0.1 nmol/l. Specific binding occurred at comparable autoradiographic densities to both human retina and choroid. Substance P and its carboxyterminal fragment, substance P(3-11), were shown to be highly potent in binding competition experiments against 125I-Bolton-Hunter-substance P. Similar concentrations of substance P(1-9), neurokinin A and neurokinin B failed to significantly alter specific binding of 125I-Bolton-Hunter-substance P. The results indicate expression of high affinity substance P binding sites in human retina and choroid.

A double-blind multicentre study comparing remoxipride, two and three times daily, with haloperidol in schizophrenia

A double-blind multicentre study comparing the efficacy and safety of remoxipride in relation to haloperidol was conducted in 160 inpatients with schizophrenic illness diagnosed according to DSM-III. The study period was 4 weeks. The mean daily dose of remoxipride (whether given twice or three times daily) during the last week of treatment was 395 mg; the corresponding dose of haloperidol was 17 mg per day. No significant difference in therapeutic efficacy was found; Brief Psychiatric Rating Scale (BPRS) median total scores dropped from 41 to 20 (remoxipride twice daily, n = 51), 43 to 20 (remoxipride three times daily, n = 44) 40 to 19 (haloperidol three times daily, n = 48) at last valid rating. According to Clinical Global Impression (CGI) 68% in the remoxipride twice daily, 58% in the three times daily and 60% in the haloperidol group were very much or much improved. Treatment-emergent extrapyramidal checklist symptoms (hypokinesia, rigidity and tremor) were statistically significantly more frequent and more severe during haloperidol than during remoxipride treatment despite a statistically significantly higher concurrent use of anticholinergic drugs in the haloperidol group. Haloperidol treated patients reported more tiredness and drowsiness than remoxipride treated patients. Also, haloperidol treated patients had a significantly higher frequency of extrapyramidal symptoms on 8 out of 10 items of the Simpson and Angus scale.

Renal disease in a patient with hereditary complete deficiency of the fourth component of complement

Hereditary complete deficiency of the fourth component of complement (C4) is an extremely rare disorder with 17 cases reported so far. Twelve of these patients suffered from a systemic-lupus-erythematosus-like illness. The patient we here describe presented with severe Henoch-Schönlein purpura (HSP) at the age of 17. Immunofluorescence of a kidney biopsy showed granular deposits of IgG, IgA, IgM, C3 and fibrinogen in the mesangium and segmentally along the basement membrane. Six years later, the patient developed hypertension and nephrotic syndrome. Renal function deteriorated rapidly. He was on hemodialysis for 12 months and then received a cadaveric kidney graft. After 2 years of uncomplicated course, microhematuria and proteinuria developed. Immunofluorescence of a transplant biopsy was virtually identical to the pattern in the patient's own kidneys. We thus conclude that the patient had recurrence of his primary disease in the graft. Three and a half years after transplantation hemodialysis had to be restarted. This unique case supports the current view that deficiency of classical pathway components predisposes to the development of immune complex diseases and that the complement system is activated via the alternate pathway in HSP. Furthermore, we assume that complete C4 deficiency was the major cause for the recurrence and unfavorable outcome of HSP in the graft.

Exercise challenge: indications and techniques

This article outlines the use of the exercise challenge as a tool for diagnosis in patients suspected of having asthma, for assessment of the severity of the condition of a patient with asthma, for assessment of the patient's response to asthma drugs, and for research in the areas of asthma and hyperreactivity. Guidelines are also provided for conducting the exercise challenge and calculating test results.

The role of inhaled steroids in the treatment of asthma

The role of corticosteroids as anti-inflammatory agents is examined. A review of the evidence shows that inhaled corticosteroids are not entirely free of side effects. However, their risk:benefit ratio is clearly better than that of systemic steroids or under-treatment. There appears to be little to choose between different inhaled corticosteroids in terms of clinical usefulness. The preference of many physicians for using inhaled corticosteroids or theophylline as first-line drugs in the treatment of asthma is questioned. New studies have shown cromolyn sodium to be equally effective as theophylline, but much safer. The widely held belief that cromolyn sodium is not effective in adults is incorrect. Although the response in children is much better, cromolyn sodium is still beneficial in many adults. Inhaled corticosteroids are more potent than cromolyn sodium, but in the author's opinion cromolyn sodium is still the preferred first-line agent because of its greater safety.

Oscillatory responses in cat visual cortex exhibit inter-columnar synchronization which reflects global stimulus properties

A fundamental step in visual pattern recognition is the establishment of relations between spatially separate features. Recently, we have shown that neurons in the cat visual cortex have oscillatory responses in the range 40-60 Hz (refs 1, 2) which occur in synchrony for cells in a functional column and are tightly correlated with a local oscillatory field potential. This led us to hypothesize that the synchronization of oscillatory responses of spatially distributed, feature selective cells might be a way to establish relations between features in different parts of the visual field. In support of this hypothesis, we demonstrate here that neurons in spatially separate columns can synchronize their oscillatory responses. The synchronization has, on average, no phase difference, depends on the spatial separation and the orientation preference of the cells and is influenced by global stimulus properties.

Psychopathological alterations in cases of symmetrical basal ganglia sclerosis

Psychopathological alterations caused by symmetrical basal ganglia sclerosis of different etiologies are described, involving cases with parathyroid gland/hormone dysfunction (some of them familial), patients after thyroidectomy, and patients with basal ganglia calcification of uncertain etiology. Initial symptomatology in a group of 62 patients is reported; chronic symptoms in another group of 35 patients were evaluated. Estimates of volume of the basal ganglia calcifications were made, in addition to precise topographical localizations by CT. In 40% the initial symptoms noted were psychiatric, compared with 50% who first presented neurological symptoms. In the group of chronic cases practically all showed intellectual impairment. There was a marked preponderance of organic affective syndromes (initially 21%, chronic 65%): the affective chronic patients can be subdivided into 37% depressive, 20% bipolar, 11% manic cases. We could find no direct relationships with regard to etiology, localization, volume or symptoms, except that extensive calcifications occur after parathyroid hormone deficiencies due to thyroidectomy and lead to more severe mental deterioration.

Effects of acute viral respiratory tract infections in patients with cystic fibrosis

To determine the effects of acute viral respiratory infections (ARI) in cystic fibrosis (CF) we studied all episodes of ARI in ten patients over a 2 year period. A daily diary card was kept on which they recorded all illnesses, including specific upper and lower respiratory symptoms, antibiotic use, and daily peak flow measurements. Recording of concurrent similar illnesses in other household members aided in confirming the onset of ARI, as did a home viral culturing technique and serial serum antibody levels against specific viral types. A total of 80% of the 35 recorded onsets of ARI (1.75/yr/subject) were confirmed by one or more of these methods. Five subjects with moderate to severe pulmonary function scores at the outset of the study had significantly greater decreases in PEFR during ARI episodes (42.4%) than those with milder disease (15.4%), and it took them significantly longer to recover to their baseline measurements (22 days vs. 15 days respectively). The majority of hospital admissions for pulmonary exacerbations were preceded by viral infections (7/8).

Cytokines in the control of beta-2 microglobulin release. II. In vivo studies with recombinant interferons and antigens

The influence of in vivo application of recombinant interferon-alpha 2c (IFN-alpha 2c) and recombinant interferon-gamma (IFN-gamma) on beta-2 microglobulin levels was studied in eight patients with chronic myelogenous leukaemia or advanced renal cell carcinoma. Data indicated enhanced beta-2 microglobulin biosynthesis in close temporary association with injection of both types of interferons. The influence of in vivo stimulation by allogenic leukocytes and the influence of renal allografts or cytomegalovirus infection on serum beta-2 microglobulin and IFN-gamma levels were also studied. Increased beta-2 microglobulin concentrations were observed again in each of these clinical situations and were closely associated with enhanced endogenous interferon production. From these in vivo data and the in vitro data presented in the preceding publication, (1) we conclude that endogenous interferon levels are crucial for the regulation of beta-2 microglobulin release in vivo.

Cytokines in the control of beta-2 microglobulin release. I. In vitro studies on various haemopoietic cells

The role of cytokines in the control of beta-2 microglobulin release from various haemopoietic cells was studied in vitro. Cell types investigated were resting cells or blasts of the T cell, B cell or monocyte-macrophage lineage. Mediators used in these experiments were r-IFN-alpha 2c, r-IFN-gamma, r-TNF-alpha, r-TNF-beta, r-IL1, r-IL2 and r-GM-CSF. Nanogram amounts of some of these mediators strongly affected beta-2 microglobulin release in vitro. r-IFN-gamma, r-IFN-alpha 2c and r-IL2 strongly enhanced and r-TNF-alpha and r-TNF-beta occasionally increased shedding of beta-2 microglobulin. r-IL1 and high concentrations of r-IFN-alpha 2c were inhibitory, whereas r-GM-CSF was ineffective. The impact of antigenic stimulation on beta-2 microglobulin release in mixed lymphocyte culture (MLC) was also studied. Stimulation with alloantigens in MLC greatly enhanced beta-2 microglobulin shedding, and this enhancement could be inhibited by a monoclonal antibody neutralizing human IFN-gamma. Among the various cell types studied, macrophages derived from peripheral blood monocytes were most susceptible to cytokine-induced alterations of beta-2 microglobulin shedding. From these data, we conclude that cytokines not only control the static expression of beta-2 microglobulin on the surface of haemopoietic cells but also largely affect their shedding.

A trial of metaproterenol by metered-dose inhaler and two spacers in preschool asthmatics

Because most young children have difficulty in coordination for correct use of metered-dose inhalers (MDI), a trial of two spacer devices attached to MDIs was performed. In 13 children with asthma, aged 2-5 years old, a collapsible bag (Inspir-Ease) and a tube spacer (Aerochamber) were tested in a double-blind crossover trial with metaproterenol (1,300 micrograms). Respiratory resistance was measured by the forced oscillation method. Thirty minutes after metaproterenol administration there was a significant decrease in resistance with both spacers, while no significant change occurred after placebo administration. There was no difference in degree of bronchodilation between the two spacers. It is concluded that metaproterenol can be safely and effectively administered to preschool asthmatics by an MDI with spacer devices.

[Treatment of aluminum-induced osteopathy with desferrioxamine in dialysis-dependent renal failure]

Presenting two patients on long-term dialysis with marked osteopathy due to aluminium intoxication we described the symptoms, pathogenesis and therapy of the disease. Two patients were treated with the chelating agent desferrioxamine which lead to a striking improvement in clinical symptoms and removal of aluminium from bone. Osteopathy due to aluminium intoxication is refractory to Vitamin D and its metabolites. Using reversed osmosis in dialysis the high aluminium levels in bone result mainly from the long-term use of phosphate binders. Therapy of choice is the treatment with desferrioxamine.