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Biomedical subjects

J Partanen

Publications and source records attributed to J Partanen.

At least 271 records · Page 15Linked to original sources
PubMed1990

Regulation by EGF is maintained in an overexpressed chimeric EGFR/neu receptor tyrosine kinase.

The effects of a ligand regulated neu tyrosine kinase were examined in NIH 3T3 cells. A chimeric construct encoding the human EGF receptor extracellular domain fused to the tyrosine kinase domain of the rat neu cDNA was expressed under the transcriptional control of the Moloney murine leukemia virus LTR promoter. This resulted in higher levels of expression of the chimeric receptor than were previously obtained from the SV40 virus early promoter in the same cells. The chimeric receptor showed strict ligand-dependent tyrosine kinase and signal transducing activities for the induction of growth-regulated biochemical activities and DNA synthesis in resting cells. The ligand-activated cells became morphologically transformed and grew in agar in the presence of EGF and TGF beta as efficiently as did the ligand-independent neu oncogene-transformed cells. Our results establish similarities between the signal pathways of the EGF receptor and the neu tyrosine kinase.

Animals↗
PubMed1990

Motor unit potentials in a mildly affected muscle in amyotrophic lateral sclerosis.

Quantitative analysis of motor unit potentials (MUPs) with spike triggering and averaging was performed from the mildly affected brachial biceps muscle of 18 patients with amyotrophic lateral sclerosis (ALS) and of 18 age-matched controls. The total MUP duration was only 6% higher in ALS patients than in controls (P less than 0.05) while the durations of the main MUP and fast components were prolonged by 63% and 194% (P less than 0.001), respectively. The number of satellites, number of fast components and amplitude were also significantly increased in the ALS group. It is concluded that determination of the duration and number of fast components and the MUP amplitude will sensitively pick up mild neurogenic affection of the brachial biceps muscle.

Action Potentials↗
PubMed1990

The effects of concurrent manipulations of cholinergic and noradrenergic systems on neocortical EEG and spatial learning.

In the spatial learning test, young animals were divided into three groups receiving saline, scopolamine (0.15 mg/kg), or scopolamine (0.8 mg/kg). Half of the animals in each group were lesioned with DSP-4 to destroy noradrenergic fibers. DSP-4 lesions did not produce any significant impairment alone or in combination with a lower dose of scopolamine (0.15 mg/kg), but they did further augment the scopolamine (0.8 mg/kg)-induced defect. In the electroencephalography (EEG) experiment, both control rats and DSP-4-lesioned rats were recorded after receiving saline, scopolamine (0.15 mg/kg), and scopolamine (0.8 mg/kg) injections. Scopolamine induced a dose- and behavioral state-dependent EEG slowing, whereas DSP-4 lesions did not change either baseline EEG activity or EEG reactivity to scopolamine.

Age Factors↗
PubMed1990

Putative tyrosine kinases expressed in K-562 human leukemia cells.

Tyrosine phosphorylation is important in the transmission of growth and differentiation signals; known tyrosine kinases include several oncoproteins and growth factor receptors. Interestingly, some differentiated cell types, such as erythrocytes and platelets contain high amounts of phosphotyrosine. We analyzed tyrosine kinases expressed in the K-562 chronic myelogenous leukemia cell line, which has a bipotential erythroid and megakaryoblastoid differentiation capacity. Analysis of 359 polymerase chain reaction-amplified cDNA clones led to the identification of 14 different tyrosine kinase-related sequences (JTK1-14). Two of the clones (JTK2 and JTK4) represent unusual members of the fibroblast growth factor receptor gene family, and the clones JTK5, JTK11, and JTK14 may also belong to the family of receptor tyrosine kinases but lack a close relationship to any known tyrosine kinase. Each of these different genes has its own characteristic expression pattern in K-562 cells and several other human tumor cell lines. In addition, the JTK11 and JTK14 mRNAs are induced during the megakaryoblastoid differentiation of K-562 cells. These tyrosine kinases may have a role in the differentiation of megakaryoblasts or in the physiology of platelets.

Amino Acid Sequence↗
PubMed1990

Taurine in normal and diseased human skeletal muscle.

Taurine content of 199 clinical muscle biopsies was determined and correlated to histometric data of 121 cases. Taurine concentration in muscles was markedly dependent on fiber type distribution, taurine being more abundant in the slow, oxidative type 1 fibers than in the type 2 fibers. Taurine concentration rose slightly with age and tended to be higher in denervations, muscular dystrophies and myotonias, but the differences from the control values were non-significant.

Adolescent↗
PubMed1990

High frequencies of B8, DR3 and C4A null alleles and immunological disorders in a family of four generations.

In a Finnish family covering four generations many members had immunological symptoms or disorders (mostly skin or joint oriented) with the presence of the B8 antigen positive Major Histocompatibility Complex (MHC) haplotype. Immunological parameters including the presence of autoantibodies, quantitative analysis of the complement components C4, Factor B (BF) and C3 and the serum capacity to inhibit immune precipitation were investigated in relation to the genetic MHC markers. The results showed the importance of the high frequency of the C4A null alleles to these disorders.

Adolescent↗
PubMed1989

Subacute cutaneous lupus erythematosus. Genetic markers and clinical and immunological findings in patients.

The role of HLA and complement genes was studied in 13 patients with subacute cutaneous lupus erythematosus. Genetic markers and by combining the major histocompatibility complex class I (HLA-A, -B, and -C), class II (HLA-DR), and class III (properdin factor B [BF] and C4) phenotyping with DNA level analysis of the C4 region. Of our patients, 54% had DR2 antigens and 50% had DR3 antigens, when the frequencies in the controls were 25% and 33%, respectively. The DR3 antigen was associated with annular skin lesions that were associated with a younger age at onset, whereas the DR2 antigen was associated with papulosquamous skin lesions and an older age at onset. The frequency of C4 null alleles was 83% in the patients and 50% in the controls. The null alleles were found in both C4A and C4B loci and were not associated with any special major histocompatibility complex haplotype. The DNA studies showed that the null phenotype mostly resulted from a gene deletion. A highly increased frequency of complement C4 null alleles may be a predisposing factor for cutaneous lupus erythematosus and especially of the subacute cutaneous type.

Adult↗
PubMed1989

Longitudinal EEG spectral analysis in early stage of Alzheimer's disease.

Twenty-four patients with mild to moderate Alzheimer's disease (AD) were studied using quantitative spectral analysis of EEG at the time of the diagnosis and 1 year later. In 50% of the patients EEG spectra from the T6-O2 derivation were either normal or mildly abnormal at baseline and did not change at 1 year. In another half of the patients the mean quantitative EEG variables (the alpha and the delta power and the mean frequency) deteriorated significantly when baseline and 1 year values were compared. The patient groups with deteriorating and stable EEGs did not differ in age, sex, age at onset or duration of the disease or clinical severity at baseline or at 1 year. Dementia also progressed significantly in both subgroups of AD patients. We conclude that even if the mean values of quantitative EEG variables analysed from the T6-O2 derivation showed distinct slowing at the time of the AD diagnosis and further deterioration 1 year later, in 50% of these early AD cases there was no EEG alteration or worsening in 1 year follow-up, suggesting heterogeneity of the disease.

Aged↗
PubMed1989

Effect of cysteamine on levels of somatostatin-like immunoreactivity and catecholamines and on electroencephalogram in the rat brain.

Cysteamine (CYS) is known to be a quite specific depletor of somatostatin in the rat brain. In the present study we investigated the effect of CYS (100 mg/kg, 300 mg/kg, subcutaneously) on levels of somatostatin-like immunoreactivity (SLI) in the brain and cerebrospinal fluid, on catecholamines in the cortex, and on spectral cortical electroencephalogram (EEG) of rat. SLI was decreased in both the cortex and the striatum (p less than 0.05) of CYS-treated rats, but no change was seen in SLI of CSF. Cortical levels of dopamine, noradrenaline and homovanillic acid were decreased (p less than 0.05) following administration of either dose of CYS. In EEG, during mobility both the frontal and occipital peak (Fp) and mean (Fm) frequencies were slowed (p less than 0.05). Frontally, the amplitude of the frequency bands 1.5-3Hz and 3-5Hz was increased (p less than 0.05). During immobility the Fp and Fm were also slowed. In frequency bands of 3-5Hz, 5-10Hz and 10-20Hz the amplitude was decreased (p less than 0.05), indicating that, in addition to theta frequency, the low voltage fast activity is also affected by CYS. According to our results, both the cortical intrinsic neurons containing somatostatin and also the ascending catecholaminergic systems are affected after the single administration of CYS concomittantly with, but not necessarily related to, changes in different frequency bands in EEG.

Animals↗
PubMed1989

Brain cholinergic enzymes and cortical EEG activity in young and old rats.

1. Cholinergic enzymes (ChAT, AChE) in different areas of the brain and cortical electroencephalography (EEG) activity were investigated in young and old rats. 2. In old rats, ChAT activity was low in the striatum, but high in the amygdala. Compared to young rats, ChAT activity in old rats was unchanged in the frontal, parietal/occipital and entorhinal cortex as well as in the hypothalamus, midbrain, hippocampus and brain stem. 3. AChE activity in old rats was lower than in young animals in the parietal/occipital cortex, hippocampus, striatum and brainstem. In other areas of the brain AChE activity was unchanged. 4. In old rats the peak frequency (Fp) of cortical EEG activity (mobility-related) was significantly lower than in young animals, both frontally and occipitally. The power of 5-10 Hz frequency band was markedly lower than in young rats. During immobility, the power of the 1.5-3 Hz and 3-5 Hz bands was lower in the frontal cortex of old rats. The power of 3-5 Hz, 5-10 Hz and 10-20 Hz bands was lower in the occipital cortex of old rats. In all of the old rats, but not in any of the young ones, symmetric high voltage activity was observed in the frontal pole of the cortex. 5. These results suggest that the age-related decrease of higher frequencies of cortical EEG activity may be related to the decrease of AChE activity in the parietal/occipital cortex. This decrease in AChE may reflect degeneration of the cholinergic synapses.

Acetylcholinesterase↗
PubMed1989

Determination of deletion sizes in the MHC-linked complement C4 and steroid 21-hydroxylase genes by pulsed-field gel electrophoresis.

In man, the genes encoding the complement component C4 (C4A, C4B) of the immune system and the steroid 21-hydroxylase enzyme (CYP21A, CYP21B) of adrenal steroid biosynthesis are located in the major histocompatibility complex (MHC). Frequent gene deletions and duplications have been described in the C4 and CYP21 genes, particularly in patients with autoimmune diseases and congenital adrenal hyperplasia. Here we report the determination of deletion sizes in 11 chromosomes with six different deletions. The deletions spanned the C4A+CYP21A, C4B+CYP21A, and C4B+CYP21B gene pairs as determined by standard Southern blot analysis. The deletion size fell within the range of 30-38 kb in all the chromosomes, as determined by pulsed-field gel electrophoresis. Because the deletion sizes in most other gene clusters are more heterogeneous, the results suggest the involvement of a specific mechanism in the generation of C4+CYP21 deletions.

Chromosome Deletion↗
PubMed1989

Iatrogenic compartment syndrome, A follow-up of four cases caused by elastic bandage.

We describe four patients suffering from lower limb compartment syndromes which were caused by constrictive bandages applied after stripping of varices. The dressing was erroneously only partially removed, when the patients started complaining of severe pain and tension in the operated legs. The damages varied from extended irreversible neuromuscular defects to lesser functional handicaps. Three patients had corrective surgery. The clinical follow up over several years showed little improvement, secondary complaints were frequent.

Adult↗
PubMed1989

EEG spectral analysis in delirium.

Spectral analysis of EEG was conducted for 51 elderly delirious patients meeting the Diagnostic and Statistical Manual of Mental Disorders III (DSM-III) criteria and for 19 controls. As a whole group, and also when subdivided according to the type of delirium, severity of cognitive decline or the type of central nervous system disease, delirious patients showed significant reductions of alpha percentage, increased theta and delta activity and slowing of the peak and mean frequencies and these changes were also obvious in individual recordings. The alpha percentage and various ratio parameters correlated significantly with Mini Mental State score, and delta percentage and mean frequency with the lengths of delirium and hospitalisation. The results indicate an association between spectral EEG changes and severity of cognitive deterioration in delirium.

Aged↗
PubMed1989

Major-histocompatibility-complex gene markers and restriction-fragment analysis of steroid 21-hydroxylase (CYP21) and complement C4 genes in classical congenital adrenal hyperplasia patients in a single population.

The gene CYP21B, encoding the steroid 21-hydroxylase enzyme of adrenal steroid biosynthesis, has been mapped to the human major histocompatibility complex (MHC). Deficiency of this enzyme leads to congenital adrenal hyperplasia (CAH). We report the phenotypes of the HLA and complement C4 and Bf genes, which are closely linked to the CYP21B gene, together with a detailed analysis of the CYP21 and C4 RFLP, in 17 Finnish families with CAH. The RFLP analysis with six restriction enzymes suggested that, altogether, 35% of the affected chromosomes had a CYP21B + C4B gene deletion, 9% an obvious gene conversion of the CYP21B gene to a CYP21A-like gene, and 3% a CYP21A + C4B duplication. The remaining 53% gave the RFLP patterns also found in nonaffected chromosomes. We also found that a 14.0-kb EcoRI RFLP marker of the CYP21 genes was strongly associated with the presence of a short C4B gene, suggesting that some of the RFLP markers found with the CYP21 probe may actually derive from C4B gene polymorphism. Three particular MHC haplotypes, each with a characteristic RFLP pattern, were found in many unrelated families. These three haplotypes accounted for 59% of the affected chromosomes in our study group, the rest (41%) of the affected chromosomes being distributed among various subtypes. The results suggest that, within a single, well-defined population such as in Finland, only a few CYP21B gene defects may constitute a substantial part of the affected chromosomes. This finding will help in genetic studies of CAH in such populations.

Adrenal Hyperplasia, Congenital↗