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Biomedical subjects

H Beckmann

Publications and source records attributed to H Beckmann.

At least 109 records · Page 6Linked to original sources

[Schizophrenia and birth seasonality--contrary results in relation to genetic risk].

In 1299 DSM III-R schizophrenics a slight excess of winter and spring births was evident when compared to the general population. However, when patients were allocated to different diagnostic subgroups according to the Leonhard classification this remained true only for those forms without obvious genetic loading (cycloid psychoses and systematic schizophrenias). On the contrary those forms with high genetic loading (unsystematic schizophrenias) showed a clearcut decrease of births in these months. This decrease, however, was significantly caused by periodic catatonics and cataphasics, but not by affect-laden paraphrenics. The findings corroborate the hypothesis that exogenous noxious agents, present in a crucial period of brain maturation, may be of etiological significance in schizophrenia with low genetic loading. Further, it was suggested that in some foetuses at high genetic risk for the disorder more abortions, stillbirths, postnatal deaths and early childhood deaths can occur, if additional exogenous noxious agents affect these individuals.

Adult↗

Differences in P300 amplitudes and topography between cycloid psychosis and schizophrenia in Leonhard's classification.

In a polydiagnostic approach, we investigated the parameters of auditory P300 in a group of 18 remitted schizophrenics and in 18 age- and sex-matched controls. All patients fulfilled the criteria of schizophrenic disorder according to DSM-III-R. Applying Leonhard's classification, patients were to be subdivided into 7 cycloid psychosis and 11 Leonhard's schizophrenics. Patients with cycloid psychosis fulfilled the operational criteria of Brockington et al. We found significantly lower P300 amplitudes in the group of Leonhard's schizophrenics than in controls and in cycloid psychosis, whereas no difference could be shown between patients with cycloid psychosis and controls. Both the maxima and the minima of the P300 field map were dislocated significantly to the right in the group of Leonhard's schizophrenics but not in cycloid psychosis.

Adult↗

Presentation of human neocortical neurons stained with the carbocyanine dye dil compared to the Golgi silver impregnation technique.

The carbocyanine dye Dil (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate) not only serves as an excellent neuronal tracer, but also produces staining of neurons similar to the results of the Golgi technique. In one aspect staining with Dil seems superior to the Golgi technique: the axons are well stained and show morphological details of their structure. The dendrites and the spines can also be studied easily so that this technique seems to be a promising alternative of the Golgi technique. The fading of the fluorescence could probably be overcome by photoconversion of the stained neurons.

Brain↗

[The early childhood form of negativistic catatonia].

In a case report the clinical manifestation of negativistic catatonia with its modified symptomatology by first onset in early childhood is presented. The symptomatology consists of negativism, negativistic excitations with (auto)aggressivity and impulsive behaviour. Development of expressive language is lacking or is arrested. Physical development is retarded. These conditions are seldom recognized but diagnosed as organic brain syndrome or more unspecifically as "pervasive developmental disorder" (DSM III-R, ICD 10).

Adult↗

Variations of monoamines and their metabolites in the human brain putamen.

The levels of the monoamines dopamine (DA), serotonin (5-HT) and norepinephrine (NE) and the monoaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were measured with HPLC-ECD in 42 samples from human brain putamen. The influence of gender and of age was investigated and correlations between the monoamines were established. The DAergic system shows a significant difference between males and females, with females having lower DA and higher DOPAC levels and a higher DOPAC/DA ratio than males. No gender-related differences of 5-HT and its metabolites were observed, nor of NE. Three different age groups (group 1: 0-9.9 years: group 2: 10-59.9 years; group 3: 60 years and older) were defined according to previous studies on ontogenesis and senescence in human brain. An increase in 5-HT levels, decrease in 5-HIAA levels and a decrease in the 5-HIAA/5-HT ratio were observed after the first decade of life. Changes in the DAergic system were seen in senescence, with decreasing DA levels and an increase in the HVA/DA ratio. DOPAC, HVA and the DOPAC/DA ratio are unaffected. NE is similar in all age groups. The analysis of the relation of the levels of the three monoamines proved a strong correlation between the DAergic and 5-HTergic systems. The nature of this relationship might have an impact on neuro-psychiatric disorders and brain function.

Adolescent↗

Heterodimerization between light-regulated and ubiquitously expressed Arabidopsis GBF bZIP proteins.

The promoters of a variety of plant genes are characterized by the presence of a G-box (CCACGTGG) or closely related DNA motifs. These genes often exhibit quite diverse expression characteristics and in many cases the G-box sequence has been demonstrated to be essential for expression. The G-box of the Arabidopsis rbcS-1A gene is bound by a protein, GBF, identified in plant nuclear extracts. Here we report the isolation of three Arabidopsis thaliana cDNA clones encoding GBF proteins referred to as GBF1, GBF2 and GBF3. GBF1 and GBF2 mRNA is present in light and dark grown leaves as well as in roots. In contrast, GBF3 mRNA is found mainly in dark grown leaves and in roots. The deduced amino acid sequences of the three cDNAs indicate that each encodes a basic/leucine zipper protein. In addition, all three proteins are characterized by an N-terminal proline-rich domain. Homodimers of the three proteins specifically recognize the G-box motif, with GBF1 and GBF3 binding symmetrically to this palindromic sequence. In contrast, GBF2 binds to the symmetrical G-box sequence in such a way that the juxtaposition of the protein and the DNA element is clearly asymmetric and hence distinct from that observed for the other two proteins. The fact that GBF1, GBF2 and GBF3 possess both distinct DNA binding properties and expression characteristics prompt us to entertain the notion that these proteins may individually mediate distinct subclasses of expression properties assigned to the G-box. Furthermore, we demonstrate that GBF1, GBF2 and GBF3 heterodimerize and these heterodimers also interact with the G-box, suggesting a potential mechanism for generating additional diversity from these GBF proteins.

Amino Acid Sequence↗

DNA binding site preferences and transcriptional activation properties of the Arabidopsis transcription factor GBF1.

The G-box is a cis-acting element found within the promoters of many plant genes where it mediates expression in response to a variety of different stimuli. This palindromic DNA motif (CCACGTGG) is composed of two identical half sites, the base pairs of which we have numbered -4 to +4 (numbering from 5' to 3'). Both half sites are involved in the binding of the bZIP protein GBF1, a member of the GBF family of Arabidopsis thaliana. Here we demonstrate using the random binding site selection method that GBF1 interacts with, in addition to the palindromic G-box, other DNA motifs that fall into seven distinct groups. All groups share the ACGT core sequence, common to most DNA motifs bound by plant bZIP proteins so far characterized. Our studies demonstrate that a high affinity GBF1 binding site is further defined by the following two parameters: first, all sites contain a G residue at position +3 (as in ACGTG) and secondly, only certain base pair combinations are allowed at positions -4, -3 and +4. Two of the identified groups (TGACGTGG and TGACGTGT) contain the base pairs TG at positions -4 and -3 and hence resemble the binding sites of another class of plant bZIP proteins (TGACGT/C binding proteins). However, GBF1 only interacts with the TGACGT sequence if the two 3' distal nucleotides (positions +3 and +4) are occupied by GG or GT. These data define the differences between a G-box binding protein and TGACGT/C binding proteins. The N-terminal domain of GBF1 is defined by a high proline content. Such regions were also identified in proteins related to GBF1. We demonstrate that this N-terminal proline-rich domain of GBF1, when fused to a heterologous DNA binding domain, stimulates transcription in both plant protoplasts and mammalian cells. These extensive DNA binding studies and the characterization of the GBF1 activation domain will facilitate both the identification of regulatory elements and the in vivo function of GBF1.

3T3 Cells↗

MRI white matter hyperintensity in neuroleptic malignant syndrome (NMS)--a clue to pathogenesis?

The case of a young female patient with neuroleptic malignant syndrome (NMS) and extended MRI white matter hyperintensity in the left parietal and both occipital lobes is reported. MRI lesions resembled findings in hypertensive encephalopathy, they were not readily compatible with CNS vasculitis. Venous sinus thrombosis could be ruled out. Vascular encephalopathy with transient white matter edema and a small residual left parietal lesion is suggested. Neurochemical implications are discussed with particular reference to a possible involvement of excitatory amino acids in NMS pathogenesis.

Adult↗

TGA1 and G-box binding factors: two distinct classes of Arabidopsis leucine zipper proteins compete for the G-box-like element TGACGTGG.

Regulatory elements containing the sequence ACGT are found in several plant promoters and are recognized by various basic/leucine zipper (bZIP) proteins. The Arabidopsis G-box binding factor 1 (GBF1), initially identified by its ability to bind to the palindromic G-box (CCACGTGG), also interacts with the TGACGT motif if this hexamer sequence is followed by either the dinucleotide GG--as found in the Hex motif of the wheat histone 3 promoter--or GT. Here we describe the isolation of an Arabidopsis bZIP protein, denoted TGA1, that also recognizes ACGT-containing sequences. However, TGA1 differs from members of the GBF family in the spectrum of base pair permutations flanking the ACGT sequence that are required for DNA binding. TGA1 primarily requires a TGACG motif and preferentially binds to those pentamers that are followed by a T residue. We show that although both TGA1 and GBF1 bind to the Hex motif (TGACGTGG), this binding can be distinguished on the basis of their specific DNA-protein contacts. Furthermore, TGA1 also differs from members of the GBF family in that it apparently does not form heterodimers with any member of this family.

Amino Acid Sequence↗

The influence of neuroleptics on specific syndromes and symptoms in schizophrenics with unfavourable long-term course. A 5-year follow-up study of 50 chronic schizophrenics.

Fifty chronic schizophrenics with severe residual psychopathology were followed up over a 5-year period. All of them had continuously received neuroleptics for many years before and throughout the period of investigation. In 60% (n = 30) of the patients positive symptoms which were unchanged in quality and severity were present throughout the period of investigation. In 28% (n = 14) of the patients marked positive symptoms persisted from the very beginning up to 1990 (in every case more than 20 years). Applying Leonhard's classification it was obvious that syndromes are roughly unchanged with respect to the preneuroleptic era. In these patients neuroleptics seemed to have only unspecific suppressing effects on affectivity. It is supposed that in schizophrenia which leads to severe residual psychopathology, Leonhard's classification is superior to the positive-negative distinction and is a promising concept for future research in etiology and therapy.

Adult↗

Deficit of birthrates in winter and spring months in distinct subgroups of mainly genetically determined schizophrenia.

The birthrates of 507 schizophrenic patients with high familial loading were compared to the general population. The patient group showed a clearcut decrease in births within a defined winter and spring period. In particular, this was obvious if Leonhard's classification of schizophrenia was applied. The hypothesis is proposed that, in some fetuses at high genetic risk for schizophrenia, an exaggerated level of abortions or stillbirths occurs if additional environmental noxious agents are present in a crucial period of brain maturation. Pertinent evidence in support of this is found in literature.

Adult↗

Sex differences and distinct subgroups in schizophrenia. A study of 54 chronic hospitalized schizophrenics.

Sex differences with regard to age at first hospitalization and residual symptomatology were investigated in 54 long-term hospitalized chronic schizophrenics. Patients fulfilled diagnostic criteria of DSM-III, Kraepelin's dementia praecox and Leonhard's group of schizophrenias as well. The severe residual psychopathology necessitated continuous hospitalization in all the patients. The 27 women and 27 men neither differed in duration of illness or period of hospitalization nor in their social environment. We found that women were older than men at their first hospitalization and exhibited more marked positive symptomatology during the course and in the residual state than men. However, regardless of the residual symptomatology, men generally received more neuroleptics. A classification of the schizophrenic patients by means of the Leonhard criteria revealed that unsystematic schizophrenics (affect-laden paraphrenia, periodic catatonia, cataphasia) of both sexes were significantly (p less than 0.001) more often married at the time of first hospitalization than were systematic schizophrenics. Further, there was an overwhelming preponderance of women among the group of affect-laden paraphrenia and, conversely, of men in the group of periodic catatonia. Presuming different etiology in affect-laden paraphrenia and periodic catatonia, our findings suggest a significantly varied frequency in the rate in which women and men are afflicted by heterogeneous subgroups of schizophrenia.

Chronic Disease↗

[Electroconvulsive therapy in treatment of acute life threatening catatonia in toxic epidermal necrolysis (Lyell syndrome)].

Toxic epidermal necrolysis (Lyell syndrome) developed in a 43-year woman treated with carbamazepine, perazine, and sulpiride for recurrent manic bipolar disorder. Five days after withdrawal of all psychotropic medication her psychiatric illness was exacerbated and a syndrome of lethal catatonia developed which was promptly treated with unilateral electroconvulsive therapy (ECT). Rapid remission of lethal catatonia after the first ECT treatment and of her affective disorder within days was achieved. According to clinical observations of the preneuroleptic era, early improvement of lethal catatonia following ECT may have been supported by concurrent high dose corticosteroid therapy for toxic epidermal necrolysis.

Adult↗

Disturbed glucocorticoid receptor autoregulation and corticotropin response to dexamethasone in depressives pretreated with metyrapone.

We studied glucocorticoid receptor autoregulation and corticotropin response to dexamethasone in depressed patients and controls, attempting to control for the confounding effect of endogenous glucocorticoids. After depletion of endogenous cortisol, depressed patients showed an attenuated suppressibility of corticotropin by dexamethasone in the face of unchanged dexamethasone plasma levels. Beta-endorphin levels were strongly correlated with adrenocorticotropic hormone (ACTH) concentrations. Although metyrapone administration resulted in a marked rise of glucocorticoid receptor sites per cell in controls, this effect was not present in depressives. These data support the hypothesis of a decreased glucocorticoid receptor plasticity and a partial steroid resistance in depression.

Adolescent↗

Cortex, white matter, and basal ganglia in schizophrenia: a volumetric postmortem study.

Postmortem volumetry of cortex, white matter, and basal ganglia was performed in 23 brains of schizophrenic patients and 23 brains of controls closely matched for gender, age, and hemisphere. Stereological methods were applied to serial coronal sections of complete hemispheres. We found no significant volume changes of cortex and white matter in schizophrenics. Striatal volume of schizophrenics was increased bilaterally reaching a significant level on the left side. Volumes of the globus pallidus were increased in both hemispheres reaching a significant level on the right side. After psychopathological differentiation, basal ganglia volume increase was also found in the subgroup of paranoid-hallucinatory schizophrenics.

Basal Ganglia↗