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Biomedical subjects

H Siemes

Publications and source records attributed to H Siemes.

At least 55 records · Page 3Linked to original sources
PubMed1977

Oligoclonal gamma-globulin banding of cerebrospinal fluid in patients with subacute sclerosing panencephalitis. Comparison of the electrophoretic pattern with that in multiple sclerosis and congenital infections.

Lumbar cerebrospinal fluid (CSF) of 8 patients with subacute sclerosing panencephalitis (SSPE) was examined by agarose gel electrophoresis. In comparison with normal controls and children with different neurological diseases (including infections, tumours and degenerative diseases) the quantitative evaluation of the pherograms by an analog computer revealed an extreme change of the gamma-globulin profile. All cases showed 6-7 abnormal subfractions consisting of 2-4 tall, markedly protruding spikes and several small intermediate fractions. The oligoclonal gamma-globulin contributed 20.1-42.5% to total protein. This particular gamma-globulin profile seems to be highly indicative of the diagnosis of SSPE. It can be distinguished from the oligoclonal pattern in patients suffering from multiple sclerosis (MS) and congenital infections. The CSF protein profile of 13 patients with MS was different from that in SSPE in that it showed 1-5 monoclonal gamma-fractions in every case with none or only one peak protuding more markedly. The percentage of all subfractions amounted to 4.5-23.8% of total protein. As in MS, the aspect of oligoclonality in 9 children with congenital infections (cytomegalic inclusion body disease, toxoplasmosis and rubella) was quite variable, as again 1-5 abnormal subfractions were detected. Their relative concentrations, on the whole ranging from 0.6-12% of total protein, was considerably lower than in SSPE.

Adolescent↗
PubMed1977

Agarose gel electrophoresis of cerebrospinal fluid proteins and analysis of the pherogram profiles by analog computer.

A micro-method of agarose gel electrophoresis requiring 1--3 ml of cerebrospinal fluid for quantitative analysis of cerebrospinal fluid proteins is described. After concentration of CSF to about 50 microliter by ultrafiltration and refractometric determination of protein, approximately 20--40 microgram of total protein are used for electrophoresis. Photometric scanning of the electrophoretic pattern at two different wavelengths permits quantitative evaluation. The pherograms are analysed by means of a modified DU-PONT analog computer. Factors which influence quantitative electrophoresis are examined. In cerebrospinal fluid of normal children 15 protein fractions are demonstrated: 2 prealbumins, albumin, 5 alpha-, 3 beta- and 4 gamma-globulins.

Adolescent↗
PubMed1976

Protein patterns of the cerebrospinal fluid in children with cerebral palsy.

Cerebrospinal fluid in 69 children with cerebral palsy (CP) of different etiology was examined by an improved method of agarose-gel electrophoresis. The protein pattern was normal in 12 cases only. In children with CP caused by congenital and postnatal infections raised psi-globulin fractions and the appearance of oligoclonal phi-globulin bands were the most obvious finding. In patients with CP due to malformations or perinatal brain damage and in children with CP of unknown etiology decreased prealbumin and increased albumin values were combined with hydrocephalus e vacuo in about half of the cases. Less frequent changes of the beta-globulin fractions were found, an increase of the beta-fraction being more rare than a decrease of the tau-globulin.

Age Factors↗
PubMed1975

[The relationship between age and the cerebrospinal fluid protein profile profile of normal children. Cellulose acetate and agarose gel electrophoretic studies].

Neuropädiatrie 6: 383--397 (1975). CSF samples of 63 normal children 2 days to 14 years of age were concentrated (ultrafiltration in "Kollodiumhülsen") and examined by electrophoresis on cellulose acetate and agarose gel. In the CSF of all children 7 protein fractions were found by cellulose acetate electrophoresis. Analysing the pherograms by the means of an analog computer 15 fractions could be separated by agarose gel electrophoresis. Compared with the children of school age the newborn showed low prealbumin, beta1-globulin and tau-globulin fractions besides high albumin and gamma-globulin concentrations owing to an increased permeability of the blood-CSF barrier. During the following weeks a low prealbumin and a high albumin fraction still was found. Children from 3 month to 2 years of age showed a moderate increase of the relative prealbumin and beta1-globulin concentration in comparison with older children. The gamma-globulin fraction was lowest beyond the third month of life and increased again in the group of the 2--14 years old children. The variation of the protein profile with age could not only be demonstrated by the more difficult agarose gel electrophoresis but also by a simple technique of cellulose acetate electrophoresis.

Adolescent↗
PubMed1975

The fractionation of cerebrospinal fluid proteins by cellulose acetate electrophoresis in children with infectious diseases of the central nervous system (author's transl).

The increased permeability of the blood-brain barrier during acute inflammation of the central nervous system leads to changes of the cerebrospinal fluid (C.S.F.) protein pattern. Initially, in the cases of bacterial meningitis, cellulos acetate electrophoresis revealed decreased prealbumin, albumin and tau-globulin fraktion whereas alpha- and gamma-globulin fractions were found increased. In later stages of purulent inflammation a hydrocephalus occurred in five children, associated with an increased amount of albumin in the C.S.F. Cases of viral meningoencephalitis had a characteristic decrease of prealbumin and increase of gamma-globulin, the lowered prealbumin values were found more often. In three cases of congenital encephalitis pathological patterns of C.S.F. proteins were still found 1--1 1/2 years postpartum. Children with acute peripheral facial palsy and febrile convulsions had a normal C.S.F. protein profile.

Acetates↗
PubMedDate not supplied

[Optimizing epilepsy therapy in children and adolescents with lamotrigine].

Lamotrigine is a broadly effective antiepileptic drug in mono- and add-on therapy for children and adolescents with focal and generalized epilepsies. Some epileptologists consider lamotrigine as the drug of primary choice in older school children and adolescents because of its good tolerability (no increase of body weight, no impairment of cognitive functions, due to new data probably no teratogenic properties). Lamotrigine can be used with good efficacy in numerable epilepsy diseases, such as tuberous sclerosis, juvenile neuronal lipofuscinosis and Rett syndrome. The first studies show that lamotrigine is also effective in children under 2 years of age. For therapy of difficult-to-treat epilepsies the combination of lamotrigine with valproate has proved as especially useful. This clinical observation is supported by new results of animal experiments. The dose-dependant and typical CNS side effects vertigo, ataxia, nausea, tremor and diplopia are found most frequently. The rate of allergic skin rashes which was very high before 1998 has decreased markedly by new dosage guidelines and is now as low as in older antiepileptic drugs. Lamotrigine does not impair cognitive functions, especially not memory and language. It has mood-stabilizing features and may improve quality of life. In animal experiments lamotrigine shows antiepileptogenic and neuroprotective effects.

Adolescent↗
PubMedDate not supplied

[New aspects in prevention of febrile convulsions].

In general, febrile convulsions have a good prognosis. The risk of death or neurologic and mental handicap is low. Though the risk of epilepsy is increased, there is no evidence that anticonvulsant treatment can prevent occurrence of later epilepsy. The aim of anticonvulsive prophylaxis is reduction of the rate of recurrences of febrile convulsions. Recent results point against the assumption that these can be prevented by long-term anticonvulsive treatment with phenobarbital or valproate. An alternative for longterm prophylaxis is intermittent short-term rectal application of diazepam suggested for children with a hightened risk of recurrences. Long-term prophylaxis with phenobarbital should only be considered in a small number of selective children.

Anticonvulsants↗
PubMedDate not supplied

[Valproate-associated hepatotoxicity--pathogenesis, clinical aspects, therapy and prevention].

The potential hepatotoxicity resulting in fatal liver failure is of major concern in treating patients with valproate (VPA). Until now there is no relevant laboratory parameter allowing early detection of impending liver failure. The major routes of VPA biotransformation are glucuronidation and beta-oxidation. There are several other pathways of degradation with formation of mono- und di-unsaturated derivates. VPA dose, patients age, co-medication (anticonvulsants, aspirin), fasting and glucose supply influence the VPA metabolism. The clinical spectrum of VPA-associated hepatotoxicity reaches from slight increases of liver enzymes without clinical manifestations over reversible slight to severe liver dysfunction to fatal liver failure. With respect to pathogenesis attention has focused on depletion of beta-oxidation and change of biotransformation to other pathways with increased synthesis of toxic unsaturated VPA derivates. Several inborn errors of metabolism, acute infections and status epilepticus seem to predispose to liver failure. Another hypothesis lies in the possible VPA-induced depression of free radical scavenging enzyme activities. On this basis N-acetylcysteine has been used successfully in treating children with severe hepatotoxicity. In the presence of certain risk factors VPA should be avoided.

Ammonia↗
PubMedDate not supplied

[Prolonged nonbacterial meningitis: clinical aspects and cerebrospinal fluid findings].

Ten to 28 days after hospital admission cell count and/or total protein concentration showed no decrease or further increase in 33 children (25 boys, 8 girls) between 2 to 15-years of age who suffered from acute aseptic meningitis (causative agents: mumps virus in 9 children, enterovirus in 5 children). Three of these children had cerebral palsy as a possible predisposing factor. The onset of prolonged aseptic meningitis was protracted in some children. At hospital admission the clinical features of this disorder differed not from those in uncomplicated acute aseptic meningitis. In 4 children a one-sided and in 4 patients a doublesided peripheral facial paralysis occurred as a transitory complication. One child showed transient arterial hypertension. EEG was normal in most of the children or revealed a slight general slowing only. Apart from a slight enlargement of the ventricles in 3 children cerebral CT showed no abnormality. Complaints like vertigo, headache, and vomiting persisted for weeks or months in part of the children. During the course of the disease CSF reflected two different reactions: 1. further increase of total protein in combination with a minimal cellular response, affecting 2-10 years old boys and girls equally; protein electrophoresis revealing the pattern of severe blood-CSF barrier disturbance, 2. persistant elevation or further increase of both cell count and total protein occurring nearly exclusively in 6-15 years old boys, associated with the CSF-protein pattern of severe blood-CSF barrier disturbance and of oligoclonal gamma-fractions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

[Long-term monitoring of therapy-induced computerized tomographic cranial changes in children with acute lymphoblastic leukemia].

PURPOSE: Long-term follow-up of cranial CT scans of children with acute lymphoblastic leukemia and evaluation of the influence of chemo- and radiotherapy on the CCT changes. PATIENTS AND METHODS: CCT scans of 68 children with non-B-ALL were analyzed retrospectively for signs of atrophy and changes in density. Patients were treated between 1981 and 1990 at the St. Anna Childrens Hospital Vienna according to the ALL-BFM protocols. Children were examined with CCT in defined periods from diagnosis until 3 years after cessation of treatment. As a control group served 69 patients with solid tumors who had not received corticoids or cranial irradiation. RESULTS: At the initial examination 56% of the ALL-patients showed CCT changes, 85% of these patients had already received corticoids. In the control group only 20% of the CCTs were found abnormal (p = 0.005). In both groups an age-dependence was found: 64% of the ALL-patients under five years of age and 22% of the patients above 5 years had initial CCT changes (p = 0.001). In the control group 39% of the patients under five years of age and 7% of the older patients showed CCT changes at the beginning of treatment (p = 0.003). The highest incidence of abnormal CCT scans (68%) was seen during intensive chemo- and radiotherapy. Until the end of therapy the incidence of abnormal CCTs decreased to 32%. After cessation of antileukemic therapy 35% of the patients whose CNS-prophylaxis included cranial irradiation, and 12% of the non-irradiated patients had abnormal CCT scans. CONCLUSION: Corticoids can cause reversible signs of cerebral atrophy. In the assessment of CCTs a physiological age-dependence of the volume of the CSF compartment has to be taken into consideration. The main reason for non-reversible CCT changes is the CNS- prophylaxis, above all the cranial irradiation, whereby younger children seem to be particular vulnerable.

Age Factors↗
PubMedDate not supplied

Cerebrospinal fluid gamma-aminobutyric acid levels in children with different types of epilepsy: effect of anticonvulsant treatment.

The mean gamma-aminobutyric acid (GABA) level in lumbar CSF of 31 children with epilepsy was not significantly different from that of 41 age-matched controls. However, when the epileptic children were subdivided into untreated patients and patients treated with antiepileptic drugs, the medication-free subgroup had a significantly lower mean CSF GABA level than nonepileptic children. Patients controlled by anticonvulsant therapy had significantly higher CSF GABA levels than untreated epileptic patients. A more detailed analysis of the children taking antiepileptic medication indicated that the only drug that significantly increased GABA in CSF was valproic acid. Analysis of CSF data with respect to the seizure type of the patients showed that, compared with controls, significantly reduced average GABA levels were present in children with infantile spasms (mostly untreated) and unmedicated generalized tonic-clonic seizures, whereas treated children with generalized tonic-clonic seizures and patients with partial epilepsy (mostly treated) did not significantly differ from controls. The data provide further evidence that impairment of the central GABA system may be involved in human epilepsy.

Adolescent↗