Dissociation between medial temporal lobe and basal ganglia memory systems in schizophrenia

The purpose of this study was to investigate basal ganglia (BG) and medial temporal lobe (MTL) dependent learning in patients with schizophrenia. Acquired equivalence is a phenomenon in which prior training to treat two stimuli as equivalent (if two stimuli are associated with the same response) increases generalization between them. The learning of stimulus-response pairs is related to the BG, whereas the MTL system participates in stimulus generalization. Forty-three patients with DSM-IV schizophrenia and 28 matched healthy controls participated. Volunteers received the Rutgers acquired equivalence task (face-fish task) by [Myers, C.E., Shohamy, D., Gluck, M.A. et al., 2003. Dissociating hippocampal versus basal ganglia contributions to learning and transfer. J. Cogn. Neurosci. 15, 185-193.], the California Verbal Learning Test (CVLT), and the n-back working memory test. The Rutgers acquired equivalence task investigates BG-dependent processes (stimulus-response learning) and MTL-dependent processes (stimulus generalization) with a single test. Results revealed that patients with schizophrenia showed a selective deficit on stimulus generalization, whereas stimulus-response learning was spared. The stimulus generalization deficit correlated with the CVLT performance (total scores from trials 1-5 and long-delay recall), but not with the n-back test performance. The number of errors during stimulus-response learning correlated with the daily chlorpromazine-equivalent dose of antipsychotics. In conclusion, this is the first study to show that patients with schizophrenia exhibit deficits during MTL-dependent learning, but not during BG-dependent learning within a single task. High-dose first generation antipsychotics may disrupt BG-dependent learning by blocking dopaminergic neurotransmission in the nigro-stiratal system.     

Supplementary sensory-motor seizures--symptomatology, etiology, and surgical management with illustrative case reports

In the past decade, owing to the advance of epilepsy surgery, growing knowledge has accumulated on the role of the supplementary motor area, described by Penfield and coworkers in the early fifties, in movement regulation and on the characteristics of seizures involving this area. In the Hungarian neurological literature this topic--despite its neurophysiological and practical clinical importance--has been hardly touched. The authors, based on their own experience obtained from surgeries performed within the framework of the "Co-operative Epilepsy Surgery Program", describe the electrophysiological features of this area, its role in movement regulation and the symptoms of epileptic seizures stemmed from or spread onto this area. Using cases as illustrations, they demonstrate the reasoning and various algorithms of the multidisciplinary examination necessary to explore the seizure onset zone and the pathways of seizure spread. Details of the surgical solution are also described.     

The advantages of axillary artery cannulation in surgical treatment of type A acute aortic dissection

There are more alternative cannulation techniques during surgery of type A aortic dissection. The most frequently used femoro-atrial cannulation method provides limited possibility for brain protection during surgery. This theory is confirmed by relatively high frequency of major brain complications in patients operated on while using this cannulation technique. During the last years cannulationis used more often, as it may provide more protection for the brain than other methods. In 2003 seven patients underwent aortic reconstruction because of type A acute aortic dissection using axillary cannulation. All patients except one were discharged after uneventful recovery. There were no postoperative neurological complications following surgery. We lost one patient due to distal progression of the dissection. He was the only patient with clinical evidence of transient postoperative brain damage. We are strongly convinced that the spectacular improvement in our results for the surgery of type A acute aortic dissection is due to the axillary cannulation, the anterograde flow and the isolated cerebral perfusion. We recommend the axillary cannulation technique as the first choice in type A acute aortic dissection.     

Acute respiratory distress syndrome of the contralateral lung after reexpansion pulmonary edema of a collapsed lung

STUDY OBJECTIVE: To report that leukocyte-mediated acute injury may develop in a nonhypoxic lung after hypoxia-reoxygenation injury of the hypoxic lung and in other systemic organs in patients with reexpansion pulmonary edema. DESIGN: Case report analysis with examination of the literature. SETTING: Intensive care unit of a university hospital. PATIENTS: Three patients who developed leukocyte-mediated acute lung injury in the contralateral lung and systemic organ injury after ipsilateral reexpansion pulmonary edema of a collapsed lung. MEASUREMENTS: To rule out the possibility that the acute lung injury in the contralateral lung was an extension of the hypoxia-reoxygenation injury, we analyzed changes in leukocyte and platelet count in the peripheral blood in relation to the development of pulmonary edema in each lung. Changes in liver enzymes were also analyzed to detect hepatic dysfunction as evidence of systemic organ injury. MAIN RESULTS: Both leukocyte and platelet counts decreased when reexpansion pulmonary edema developed, and decreased further when acute lung injury developed in the contralateral lung (F = 8.42, p = 0.037 for leukocytes, and F = 17.66, p = 0.01 for platelets). Significant hepatic dysfunction developed, as evidenced by increases in both serum bilirubin (p = 0.001) and lactic dehydrogenase, indicating the presence of systemic organ injury. CONCLUSIONS: The hypoxia-reoxygenation injury of one lung can induce acute lung injury in the other lung and systemic organ injury.     

Short communication: seasonal onset of menopause?

BACKGROUND: Seasonal variations of reproductive functions in wild mammals are well known. Similar but blunted seasonal trends have also been described for humans. METHODS: We performed a questionnaire-based study of 149 patients that was designed to search for environmental influence on symptom presentation among patients attending an open menopause service. RESULTS: The evaluated data show a conspicuous seasonality in cessation of menstrual bleeding, with a higher peak after the vernal (spring) equinox and a lower one after the autumn equinox. CONCLUSIONS: Of the several environmental factors considered in this study, the sequence of seasons seems to affect most obviously the process leading to the loss of menstrual cycling. The triggering factor(s) eliciting the onset of the menopausal process and the mediators involved, however, need further analysis.     

Prevention of schizophrenia

Schizophrenia is a complex mental disorder with interactive neurodevelopmental, genetic, environmental, and psychosocial risk factors. Before the onset of frank psychotic symptoms, predictive clinical signs, neurocognitive abnormalities, and neurobiological dysfunctions (functional and structural brain alterations and molecular genetic features) can be detected. These markers are of special interest because with an appropriate assessment, the onset and prognosis of psychosis and the therapeutic response may be predicted. In this paper, the authors review these vulnerability markers, providing a scientifically founded and clinically oriented framework for the prevention of schizophrenia.     

C-reactive protein levels determined by an ultrasensitive method in a healthy Hungarian population

INTRODUCTION: C-reactive protein (CRP) is a well-known acute phase protein. The concentration of CRP in serum is increased in response to inflammatory stimuli. Increased levels serve to identify organic disease, to monitor disease activity and to assist differential diagnosis. AIM: The aim of the authors' cross-sectional study was to determine CRP distribution of the healthy Hungarian population. METHOD: 207 (79 male, 128 female; mean age: 4 +/- 68 years) healthy blood donors were enrolled for the study. The following parameters were registered: sex, age, body mass index, smoking habits, diabetes mellitus and blood pressure. Serum samples were assayed for total serum cholesterol, triglyceride, erythrocyte sedimentation rate, hemoglobin and for white blood cell count. CRP was measured by ultrasensitive, particle enhanced immunoturbidimetric assay. RESULTS: CRP levels were less than 5 mg/L in 81% of the blood donors. Mean level of CRP in the study population was 3.57 mg/L (SD +/- 5.33); the distribution was comparable to the data of already published studies. Comparing laboratory parameters and the risk status stratified according to CRP levels (less or more than 5 mg/L) significant differences were found in BMI (p = 0.0015), in total serum cholesterol (p = 0.0136), in triglyceride (p < 0.0001), in erythrocyte sedimentation rate (p < 0.0001), in white blood cell (p = 0.0007) and granulocyte count (p = 0.0014). Significant correlation was found between age and the concentration CRP (r = 0.22; p = 0.0011). CONCLUSION: The CRP measurement by ultrasensitive method is suitable for cardiovascular risk estimation in apparently healthy men and women. Risk prediction adapted for the Hungarian situation may be stimulated by these data.     

Prevalence of patellofemoral pain syndrome. Evaluation of the role of biomechanical malalignments and the role of sport activity

INTRODUCTION: Disorders around the patella are the most frequent knee complaints seen in adolescents. In the literature many intrinsic and extrinsic risk factors have been linked to Patellofemoral Pain Syndrome (PFPS), but the role of these risk factors is controversial. AIM: The goal of this study was to evaluate the prevalence of PFPS in a group of adolescents aged 12-20 years in Hungary, and to gain more information on the relationship between the biomechanical anomalies of the lower extremity and the PFPS. MATERIAL AND METHODS: In this epidemiological study the authors investigated the effect of sporting activity in the maturation of symptoms among 586 randomly selected students. Different physical examinations, anthropometric measurements, stability tests, footscan analysis were performed. RESULTS: Concerning the prevalence of this syndrome they could not find any differences between males (n = 60, 20.41%) and females (n = 61, 20.89%). The authors could not identify any statistically significant intrinsic risk factors, although changes in the Q angle may be linked to increased prevalence of PFPS. The study supports the theory of the importance of "overload", for there was a significant correlation between the prevalence of PFPS and the different levels of sporting activities (competitive, recreational and non-athletes). CONCLUSION: The authors concluded that the prevalence of PFPS among Hungarian students is 20.65%.     

'Designer' tumors in mice

We have developed and tested successfully a general method based on Cre-mediated recombination that can be used for ubiquitous or tissue-specific expression of protein products, including tumor-inducing oncoproteins. Depending on the specificity of a chosen promoter driving cre expression, tumors develop by design in bitransgenic mouse progeny derived by crossing Cre-producing mice with partners carrying a dormant oncogenic transgene (targeted into the 3' noncoding region of the cytoplasmic beta-actin locus) that becomes functional after excision of a 'floxed' DNA segment. To provide proof-of-principle, we have used as models transgenes encoding the polyomavirus middle T antigen (PVMT) and the T antigens of the SV40 early region (SVER). Cre-dependent activation of widespread SVER expression resulted in hyperplasias or invasive tumors affecting particular visceral smooth muscles, whereas Cre-dependent, mammary gland-specific expression of PVMT-induced adenocarcinomas, according to plan. Unexpectedly, we also encountered spontaneous (Cre-independent) oncogene expression occurring as a rare event, which simulates the initiation of sporadic tumors and leads to PVMT-induced hemangiomas and mammary carcinomas or SVER-induced disseminated sarcomas, thus, revealing particular tissue susceptibilities to the actions of these oncoproteins.