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B Scheidt

Publications and source records attributed to B Scheidt.

12 recordsLinked to original sources

Substance P, mean apnoea duration and the sudden infant death syndrome (SIDS).

In order to evaluate disturbances of the respiratory control in the first year of life in children with a statistically enhanced risk of SIDS, substance P-like immunoreactivity (SPLI) in plasma and mean apnoea duration (MA) were examined. 4 groups of infants were investigated: Controls, full-term infants with anamnestic SIDS-risk factors, preterm infants with additional risk factors and preterm infants without such factors. Infants aged from -4(corrected age) to 63 weeks. SPLI in plasma was determined by a specific, homologous radioimmunoassay. The SPLI-level was significantly higher in controls (n = 41; means +/- SE = 36.37 +/- 4.86 pg/ml) than in preterm infants without (n = 21; 25.41 +/- 5.54 pg/ml) or with additional anamnestic risk factors (n = 111; 25.89 +/- 3.09 pg/ml). SPLI was higher in full-term SIDS-risk infants (n = 150; 30.73 +/- 2.35 pg/ml) than in the preterm groups. There is a significant age dependence in the groups full-term SIDS-risk infants and preterm infants with additional risk factors. During maturation the SPLI-level in plasma rises in these groups from lower values. The MA-values were determined by means of a daytime polygraphy. There is an age dependence of the MA-values during active sleep in full-term SIDS-risk infants and in preterm infants with additional anamnestic risk factors. In the age group 4-17 weeks (peak of SIDS frequency) in active sleep the MA-values were significantly higher in all 3 risk groups than in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans

[Sudden and unexpected infant death].

SIDS is a topical problem in pediatrics. The cause of SIDS is still unknown. The paper considers different possible pathomechanisms and on the basis of different observations a variety of hypotheses: There is the apnoe hypothesis, the sleep hypothesis, the QT-hypothesis, the arousal hypothesis and the functional deficit primarily concerning the reticular formation of the brainstem. Therefore there is an urgent need for screening programms to find out children at risk of SIDS. Finally, aspects of prophylaxis and treatment in case of recognized risk are discussed.

Humans

[Risk of sudden infant death: recommendation for an early detection and prevention program].

The cause of sudden infant death syndrome is still unknown. Therefore, screening systems for its early diagnosis must refer to factors likely involved the multifactorial origin of this syndrome. In this paper a SIDS prevention program is presented. Children with a history of high risk for SIDS were polysomnographically examined. Particularly the respiration pattern was investigated. If there was a demonstrable disturbance of respiration control the children were prophylactically treated with aminophylline.

Germany, East

Factor VIII activity and factor VIII related antigen in newborns.

Factor VIII procoagulant activity and factor VIII related antigen were examined in 20 full-term and preterm newborn infants during the first days of life. The control group involved 15 adults volunteers. Factor VIII activity was estimated by a one-stage test and factor VIII related antigen was determined by immunelectrophoresis according to Laurell, using our own rabbit antiserum. The following results were obtained:--Factor VIII activity during the first 3 days of life did not differ from the normal range of the adult controls.--The concentration of factor VIII related antigen in newborns was markedly higher than in adults on the first, and to a lesser extent on the second, day of life.--The antigen concentration decreases on the second and following days of life to adult levels. The cause of this discrepancy cannot be completely explained but possible reasons are discussed.

Age Factors

[Determination of the concentration of free magnesium ions in hemolysates of oxygenated and deoxygenated packed human erythrocytes].

Concentrations of ionized magnesium in hemolyzates of oxygenated and deoxygenated human erythrocytes were measured directly by means of an ion exchange method. At total concentrations of hemoglobin of 8 mmol/l H2O and total magnesium of 3.6 mmol/l H2O, mean values of [Mg2+] were found to be 0.45 in the oxygenated state and 0.57 mmol/l H2O in the deoxygenated state. The difference of 0.12 +/- 0.1 mmol/l H2O is considerably smaller than corresponding literature data obtained from equilibrium calculation.

Erythrocytes

[An ion exchange method to determine free metal concentrations, adapted for use in biological fluids: methods and determination of (Mg2+)].

An ion exchange method for measuring concentrations of free (ionized) metal ions and its application to the determination of [Mg2+] is described. A surface sulfonated polystyrene material is used as the "twodimensional" cation exchanger. The sample-volume is 1 ml. About 50 determinations can be performed within 1 hr having a standard error of +/- (2-4)% in the optimal range of measurement. Advantages and disadvantages of the method compared with other ones are demonstrated and discussed. Free Mg2+ ion concentrations were measured in solutions containing pyrophosphate as well as haemoglobin and compared with those which were determined by equilibrium calculation or ultrafiltration.

Cation Exchange Resins

[Anamnestic factors in at-risk SID children with peculiar breathing pattern].

436 out of about 9000 infants who were born between April 1987 and November 1990 in Jena were selected by means of a risk score for a polygraphy monitoring. This score contains anamnestic factors of the mother and the infant which are characteristic of an enhanced risk for the sudden infant death syndrome (SIDS). We performed a day-time polysomnography (ECG, heart rate, respiration, EEG, EOG, EMG) with a sleep duration of at least one hour. 23 of the infants investigated demonstrated abnormal breathing patterns (increased mean apnea duration, apneas longer than 15 s, apneas with bradycardia) and were treated with aminophylline to prevent a possible SIDS event. Now we investigated the statistical relation between 26 anamnestic factors of our risk score and the need for treatment. In univariate statistical comparisons treated infants differed from untreated infants concerning the occurrence of intraventricular haemorrhages (IVH), the gestational age (GA) (preterm of fullterm) and the occurrence of hyperbilirubinemia (HB) in their anamnesis. In a multivariate analysis with all 26 factors the birth weight was the third important factor beside IVH and GA, but only factor IVH was statistically significant. A cluster analysis of the variables with respect to the separation of the two groups of infants indicates that the variables IVH, GA and HB strongly correlate. In the light of these results we can underline that abnormal breathing patterns can be expected especially in infants with IVH, short GA and low birth weight.

Aminophylline

[The diagnosis of sleep apnea--possibility for the prevention of SID?].

Groups of children with a statistically enhanced risk for SIDS: siblings of SIDS-victims and other full-term and preterm infants with anamnestic signs for an enhanced risk of SIDS and a control group of healthy infants without anamnestic signs of risk were polysomnographically investigated in the first year of life. The mean apnoea duration (MA-value estimated by frequency and length of apnoeas greater than or equal to 3s) in the sleep states active and quiet sleep was calculated. During active sleep there is a significant inverse correlation between MA and postnatal age in the full-term and preterm SIDS-risk infants but not in the controls and siblings of SIDS-victims. In all age groups there are some children in the full-term and preterm infants with extremely enhanced MA-values. For 6 age groups of the first year of life the 90% percentile of the MA-value was calculated separately in the sleep states active and quiet sleep to select infants with an abnormal breathing pattern. This limit could be a help for the decision on therapy.

Electrodiagnosis

[A screening program for detecting children with an increased SIDS risk (sudden and unexpected infant death)].

The prospective study presented conducted to prevent SIDS (sudden infant death syndrome). One of the proposed hypotheses on SIDS postulates a brainstem abnormality in the neuroregulation of cardiorespiratory processes. Therefore we characterized cardiorespiratory control mechanisms by examining the neurotransmitter substance P in plasma and polysomnographic investigations. With respect to the probable multifactorial origin of SIDS we selected children firstly anamnestically by means of an epidemiologically evaluated pre-, peri- and postnatal risk score. We reported the results of 208 polysomnographically and biochemically examined children anamnestically selected from a group of 2500 neonates. Examinations were performed on infants aged 2-4 weeks up to 1 year. To characterize respiratory control, length and frequency of apnoeas were separately estimated by means of polysomnography in the sleep states active and quiet sleep. If there were polygraphic risk factors representing a disturbance of respiratory control, the children were prophylactically treated with aminophylline 3 x 3 mg/kg b.w. for 4 weeks. We found a significant age dependence both of the mean apnoea duration in active sleep and the substance P level in plasma in the SIDS-risk group but not in the controls. High mean apnoea duration was correlated with low substance P level in the first months of age in SIDS risk infants selected anamnestically. This may reflect a delayed maturation of respiratory control mechanisms. In this way the polysomnography and the investigation of the neuropeptide substance P may be useful for a screening method indicating wether the respiratory control mechanisms are mature or not.

Aminophylline