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Biomedical subjects

J Schaub

Publications and source records attributed to J Schaub.

At least 55 records · Page 3Linked to original sources
PubMed1993

Amplification of a Y-chromosomal DNA sequence by the polymerase chain reaction for documentation of residual recipient cells in small samples from bone marrow, peripheral blood and cerebrospinal fluid after bone marrow transplantation.

The long arm of the human Y-chromosome contains about 800 to 5000 copies of the tandemly repeated DNA sequence DYZ1. A major part of the repeating unit (pHY10) has been cloned and sequenced. Primers were designed to match a part of this repeat sequence for the amplification of a 154 bp fragment spanning the EcoRI restriction site of the unit. Typical dilution experiments showed that this polymerase chain reaction (PCR) method allows the detection of 5 to 10 male cells among 100,000 female cells, or in 500 microL of cerebrospinal fluid containing only one cell per microL. In addition, the quality of the DNA used for the amplification reaction is less critical, thus allowing analysis of long-term stored samples such as bone marrow smears or dried blood stains spotted onto filter paper, which might contain partially degraded DNA. We applied this technique to detect residual host cells in the clinical setting of human sex-mismatched bone marrow transplantation (BMT). Fourteen patients, receiving transplantations because of leukemias could be supervised so far. Throughout the whole period of monitoring (days +14 until +911 post BMT; median: 160 days), residual host cells were detected in all but three patients. Persistence of host cells in the early phase post-BMT was mostly transient and probably due to long-term surviving host T-lymphocytes. Reappearance of host cells several months after BMT is highly suspicious of relapse from the underlying malignancy. Due to its high sensitivity, PCR is a valuable tool in monitoring the switch from recipient to donor cell population.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1993

Faecal excretion in infants.

Data on normal defaecation patterns in relation to diet during the first months of infancy are very limited. We therefore investigated in a prospective study faecal weight and gastro-intestinal passage time of breast fed (n = 12) and formula fed (n = 14) male infants. These were studied in 72 h collecting periods at the age of 17, 35, 57, 87 and 113 (+/- 4) days. Breast fed infants had a significantly lower daily dry faecal weight than formula fed infants in all periods investigated (median at the age of 113 days: 0.28 (0.17-0.75) g/kg and 0.81 (0.22-1.2) g/kg, respectively). Breast fed infants showed a large variation of gastro-intestinal passage time (6.79 h [range: 1.79-13.38 h] at the age of 17 days, 21.84 h [range: 5.41-75 h] at the age of 113 days). Comparable values of formula red infants were 13.75 h (range: 7.13-35.25 h) and 17.42 h (range: 5.38-36.5 h). Despite the efforts of approximation of infant formula to breast milk, differences of defaecation patterns in relation to diet are still relevant at this age and have to be considered in clinical practice.

Breast Feeding↗
PubMed1993

Isolated defect of peroxisomal beta-oxidation in a 16-year-old patient.

We describe a 16-year-old boy suffering from psychomotor retardation, sensorineuronal hearing impairment, peripheral neuropathy, hepatosplenomegaly, short stature and delayed puberty. Postnatally, muscular hypotonia, mild facial dysmorphism and delayed fontanelle closure had been noticed. At the time of our examination, adrenal cortical function was normal. Biochemical analysis revealed accumulation of very long (> C22) chain fatty acids in plasma and fibroblasts. Furthermore, elevated levels of intermediates of bile acid synthesis and phytanic acid were detectable. These findings are consistent with a defect in the peroxisomal beta-oxidation system. A generalised defect of peroxisomal function was excluded by normal plasmalogen levels in erythrocytes and normal plasmalogen de novo synthesis in fibroblasts. Immunoblotting of the peroxisomal beta-oxidation enzymes gave normal results suggesting retained immunoreactivity but catalytic inactivity of one of the enzymes involved, probably either the trifunctional protein or the peroxisomal ketothiolase. This case markedly differs clinically from the few published reports on isolated deficiencies of peroxisomal beta-oxidation. Among the patients with comparable biochemical findings, this is the first report of survival into adolescence.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1993

Comparison of umbilical arterial versus umbilical venous blood pH correlated with arterio-venous glucose difference and cardiotocographic score.

The value of clinical parameters and umbilical arterial blood pH as indicator of prenatal hypoxia is disputed. In a prospective study of 86 vaginally delivered full-term infants, cardiotocographic (CTG) findings obtained 0-30 min and 30-60 min before birth were compared to pH values, O2 and CO2 partial pressures and glucose difference in umbilical arterial and venous blood. CTG findings were expressed as a score, higher values indicating fetal hypoxia. The venous but not the arterial blood pH was significantly related to the later (0-30 min) CTG score. The arterio-venous glucose difference was significantly related to both CTG scores. There was a significant statistical relationship between glucose difference and venous but not arterial blood pH. The later CTG score (0-30 min) also correlated significantly with O2 and CO2 partial pressures and base excess in the umbilical vein of all vaginally born infants. If CTG is accepted as an objective indicator of fetal hypoxia before birth, the arterio-venous glucose difference, and in the investigated range of pH-values, umbilical venous blood pH are more suitable than the arterial blood pH to ascertain the peripartal situation of the newborn.

Asphyxia Neonatorum↗
PubMed1993

Monitoring of chimerism after allogeneic bone marrow transplantation with unmanipulated marrow by use of DNA polymorphisms.

Highly polymorphic tandemly repetitive DNA sequences provide powerful genetic markers for the identification of individuals by restriction fragment length polymorphisms (RFLP) even in close relatives. Over a three-year period, 61 consecutive patients from a single institution undergoing allogeneic bone marrow transplantation (BMT) for various hematological diseases were grafted with unmanipulated marrow and followed for the development of hematopoietic chimerism. Three synthetic oligonucleotide probes homologous to the so-called minisatellite or variable number of tandem repeat (VNTR) sequences were evaluated in the clinical setting of BMT for their usefulness: (i) to document marrow engraftment or rejection; (ii) to elucidate the kinetics of mixed chimerism; and (iii) in providing a sensitive tool for early detection of relapse. In addition, in patients with CML karyotyping and analysis of bcr/abl gene rearrangement was performed. Using this panel of three oligonucleotide probes, informative markers specific for donor or recipient RFLP could be demonstrated in all cases. Engraftment could be documented in all patients surviving beyond day +14 after BMT. Mixed chimerism was detected in 14% of the patients in the early phase (day +14 to day +78) after BMT but only one patient turned out to become a long-term stable mixed chimera. These results support the hypothesis that lymphocytes of recipient origin surviving the conditioning regimen may considerably contribute to mixed chimerism early after BMT. Long-term stable mixed chimerism is a rare event after BMT with unmanipulated marrow. Simultaneous analysis of chimerism after BMT by VNTR-RFLP, karyotyping, and detection of bcr/abl rearrangement in patients with CML showed corresponding results in nine out of 12 patients. In three patients either one of the methods failed to detect residual recipient cells in the early phase after BMT. Therefore different methods for assessment of mixed chimerism seem to complement rather than to exclude each other. Eleven patients who all exhibited complete chimerism early after BMT relapsed from their underlying disease. In seven of these patients grafted for acute leukemia, analysis of DNA-RFLP had been performed shortly before clinical relapse (30-86 days) and failed to herald relapse. As the sensitivity for the detection of the minor cell population by analysis of DNA-RFLPs is approximately 1%, these data may indicate that relapse of acute leukemia after BMT is characterized by a sudden increase in the percentage of recipient blast cells not detectable even by frequent RFLP analyses.

Adolescent↗
PubMed1992

Longitudinal zinc balances in breast-fed and formula-fed infants.

Longitudinal zinc (Zn) balance studies were performed under domestic conditions in term breast-fed (n = 10), term formula-fed (n = 5; Zn concentration in the formula: 4 mg/l) and preterm formula-fed (n = 3) infants during the first 17 weeks of life. Samples of milk, urine and feces were analyzed by atomic absorption spectrometry. The median daily Zn intake in breast-fed infants decreased from 0.592 (0.457-0.829) mg Zn/kg body weight to 0.151 (0.095-0.304) mg Zn/kg body weight in the first 17 weeks of life; comparable values for bottle-fed term infants were 0.58 (0.511-0.701) and 0.674 (0.529-0.731) mg Zn/kg body weight. The median percent retention of Zn intake was 27 (-60 to 81.4)% in breast-fed infants and 21.5 (-42 to 64)% in formula-fed infants. In view of the urinary and fecal Zn losses measured, a daily intake of 0.3-0.5 mg Zn/kg body weight is considered to be sufficient to ensure a Zn retention equivalent to breast-fed infants. This requires a Zn concentration of 2-3 mg/l of Zn depending on milk volume intake.

Bottle Feeding↗
PubMed1992

[Sodium and potassium metabolism in infancy].

BACKGROUND: Recommendations for the concentration of most nutrients in infant formulas are based on their concentration in human milk. Industry succeeded in adapting sodium and potassium content in infant formulas to concentration found in human milk. Whether this adaptation affects on infants' mineral balances was studied in breast-fed and artificially-fed infants. METHODS: Sodium and potassium balances were performed in 16 term male infants from their 3rd until their 17th week of life. The balances were performed at home and comprised up to five periods in intervals of three to four weeks. Each balance period consisted of subsequent three 24 h collections of milk, stool and urine samples. Ten infants were breast-fed, six received an adapted infant formula supplemented with copper, zinc and iron. RESULTS: The breast-fed infants got a mean intake of 1 mmol Na/kg b w x day and a mean intake of 1.8 mmol K/kg b w x day. Man retention was 0.4 mmol Na and 0.7 mmol K/kg b w x day. The formula-fed infants received 1.9 mmol Na/kg b w x day and 2.1 mmol K/kg b w x day. Na- and K-retention in this group was 0.5 and 0.6 mmol/kg b w x day respectively. Although sodium intake in the formula-fed infants was nearly twice as much as in the breast-fed infants the difference in sodium retention was only small (0.4 vs 0.5 mmol/kg b w x day). The formula-fed infants got more potassium than the breast-fed infants, but potassium retention was the same in both groups. CONCLUSIONS: With the adapted infant formula of this study the artificially fed infant was as well supplied with sodium and potassium as the breast-fed infant. A further reduction of the sodium concentration seems not to be useful.

Animals↗
PubMed1991

Iron availability from an infant formula supplemented with bovine lactoferrin.

Iron balance studies were performed in 16 term infants from their 3rd until their 17th week of life. The balance studies were performed at home and comprised five periods with an interval of 3 to 4 weeks, each consisting of three 24-hour collections of milk and stool samples. Seven infants were fed an adapted infant formula supplemented with bovine lactoferrin (100 mg/100 ml) and nine received the same formula without lactoferrin. The lactoferrin supplemented group received 169 micrograms iron/kg b.w. x day and retained 63 micrograms/kg b.w. x day. The mean iron intake of infants fed with the adapted formula without supplementation of lactoferrin was 118 micrograms/kg b.w. x day. The retention of iron was 43 micrograms/kg b.w. x day. Mean percentage retention of iron in the supplemented group was 36%, in the non-supplemented group 28%.

Biological Availability↗
PubMed1991

Successful stimulation of autologous bone marrow recovery by GM-CSF and IL-3 after an unrelated donor BMT for juvenile CML complicated by graft failure.

We report the case of a boy with juvenile chronic myeloid leukemia (jCML), who after initial treatment with interferon alpha-2 (IFN) and hydroxyurea underwent bone marrow transplantation (BMT) from a matched unrelated donor complicated by graft failure. Subsequent stimulation of hematopoiesis by GM-CSF and IL-3 promoted autologous recovery. In contrast to the course of disease pre-BMT, the boy is now off any therapy remaining in complete remission more than 500 days after BMT.

Bone Marrow↗
PubMed1991

Remission of juvenile chronic myeloid leukemia following graft failure of an unrelated marrow transplant and autologous recovery of marrow function promoted by GM-CSF and IL-3.

The unusual course of a boy with juvenile chronic myeloid leukaemia is presented. After bone marrow transplantation (BMT) from an unrelated donor followed by graft failure and subsequent stimulation by rhu GM-CFC and II-3, this patient experienced complete recovery of autologous haematopoiesis. At 17 months post-BMT the patient was off any therapy with completely normal blood counts and no signs of disease.

Bone Marrow Transplantation↗
PubMed1990

Trace element excess in PKU diets?

Knowledge of trace element requirements of infants with phenylketonuria (PKU) fed a semisynthetic diet is limited. Three infants with PKU detected early were studied longitudinally in classical balance studies for 72 h, under domestic conditions, at the ages of 2, 5, 8, 12 and 16 weeks. Iron, copper and manganese concentrations in the diet and faeces were determined by atomic absorption spectroscopy. The median concentrations in the diet (4.8 mg Fe/L, 1.7 mg Cu/L, 0.43 mg Mn/L) exceed those in human milk. This is mainly due to supplementation of the amino acid preparation used. The increased intake led to a significantly higher daily retention of Cu and Mn from the PKU-diet fed, with a median of 0.17 mg Cu/kg and 6.4 micrograms Mn/kg body weight; the median retention of Fe was 0.24 mg Fe/kg. Our results confirmed the doubts about the suitability of the present trace element supplementation in formula for infants with PKU during the first four months of life.

Body Burden↗
PubMed1990

[Anamnesis of brain-originated vision disorders].

A questionnaire for the subjective assessment of cerebral visual disorders was administered to 269 brain damaged patients. The patients' subjective complaints were correlated with the outcome of objective diagnostic procedures (visual perimetry, visual search, spatial contrast sensitivity, visual evoked potentials, depth perception, light- and dark-adaptation, reading, colour vision). A significant correlation was found between subjective complaints and objective diagnostic results for all fields. The prediction of visual impairments on the basis of subjective complaints and verified by objective tests was correct in 80 to 98% of the brain damaged patients tested. Interrater reliability was about 0.84. Thus, the questionnaire is suitable for the assessment of cerebral visual disorders because of its simplicity, short administration time (10-15 min) and high predictive value.

Accommodation, Ocular↗
PubMed1990

[Arterial thrombosis in a premature infant].

A preterm infant of 30 weeks gestation developed thrombosis of the left arteria femoralis on his fourth day of life. Continuous intravenous heparinization with 350 to 750 U/kg bw/d was performed during the course of several weeks. Although arterial thrombosis in term and preterm infants is not a rare event, there are no generally accepted guidelines for treatment. In this article alternatives of treatment--namely surgical management, thrombolytic therapy, heparinization and supportive therapy are discussed.

Blood Coagulation Tests↗
PubMed1990

Urinary zinc excretion in infancy.

In view of the conflicting data on urinary Zn excretion in infancy we investigated the possible influence of contamination, collecting methods, nutrition (human milk versus formula) and longitudinal changes during the first 16 weeks of life. Methodical investigation showed that special attention is necessary to avoid contamination due to the use of Zn-containing baby creams in the genital region. The sampling device for collection should include the smallest area of skin possible and the use of Zn-containing baby creams has to be avoided both during the collection and at least 24 hours prior to urine collection. Previous fractional urine sampling of the collecting method to be evaluated proves that erroneously high values are not obtained at the beginning of collection. Midstream urinary samples reduce the possibility of contamination. Increased urinary excretion was shown in pre-term infants under theophylline or coffeine medication. The median daily urinary Zn excretion in healthy breast-fed term infants declined significantly from 0.063 (0.027-0.111) mg per kg body weight at the age of 2 weeks to 0.018 (0.004-0.059) mg per kg body weight at the age of 16 weeks. Comparable values for formula-fed term infants were 0.029 (0.025-0.063) mg per kg body weight initially and 0.025 (0.007-0.059) mg per kg body weight at the end of the study. These values can be used as reference values for the urinary Zn excretion of healthy infants.

Aging↗
PubMed1990

Selenium balances in young infants fed on breast milk and adapted cow's milk formula.

Selenium intake, renal and fecal excretion, and retention were determined in 11 breast-fed term infants and in 9 term infants fed with an adapted cow's milk formula. In most cases three-day-balances were determined five times at the age of 2, 5, 8, 12, and 16 weeks. Analytical determination of selenium was by atomic absorption spectroscopy with a selenium hybrid system after wet ashing of samples. The mean breast milk concentrations of selenium show a significant decrease in the course of lactation from 31.0 micrograms/L in the first collecting period to 17.6 micrograms/L in the last one. The two formula milks contained 11.8 and 7.7 micrograms/L. Intake in the breast milk group was higher than in the formula group, whereas absolute renal and fecal excretion were essentially the same. This leads to a higher selenium retention in the breast-fed infants than in the formula-fed infants, where most of the balances are negative.

Adult↗
PubMed1989

Lissencephaly, abnormal lymph nodes, and T-cell deficiency in one patient.

We report on a child with lissencephaly type I, abnormal lymph nodes, and immunodeficiency, associated with recurrent infections, autoimmune disease, spastic tetraplegia, and psychomotor retardation. Diagnostic measures included cranial computer tomography (CT) and magnetic resonance imaging (MRI) scanning, several in vivo and in vitro immunological tests, and histology of skin, lymph nodes, and liver including electron microscopy and immunohistology. Despite medical supervision, the child died at age 4 years. A common pathogenetic mechanism of defective migration of neurons and the dysmaturation of lymph nodes is most probable. The T-cell deficiency may represent a common defect of the development of both neuronal and lymphatic tissue, as the six-layered cerebral cortex and the B-cell areas in lymph nodes develop at about the same gestational age. A common defect could also be assumed involving genetically determined cell surface proteins.

Brain↗
PubMed1989

Longitudinal manganese and copper balances in young infants and preterm infants fed on breast-milk and adapted cow's milk formulas.

1. Mn and Cu intake and retention in twenty full-term infants and six preterm infants were studied on the basis of 72 h balances. The age of the infants was 2-16 weeks and the gestational age of the preterm infants (triplets) 34 and 36 weeks. Three nutrition schemes were pursued: breast-fed, formula-fed with unsupplemented adapted formula and formula-fed with trace element supplementation. 2. The mean Mn concentration of all breast-milk samples (n 2339) was 6.2 micrograms/l. The two formulas had similar Mn concentrations (77 and 99 micrograms/l) but had different Fe, Cu (121 and 619 micrograms/l), Zn and I contents. The mean Cu concentration in mother's milk was 833 micrograms/l. 3. The following mean daily Mn intakes and retentions (micrograms/kg) respectively were measured: breast-fed full-term 1.06 (SD 0.43) and 0.43 (SD 0.65), formula-fed full-term 14.2 (SD 3.1) and 2.8 (SD 4.8), formula-fed preterm 15.0 (SD 2.2) and 0.06 (SD 5.87). The results for Cu were 114.5 (SD 22.3) and 88.0 (SD 46.5) micrograms/kg in breast-fed, 19.8 (SD 4.2) and 4.6 (-11.5-9.6) in the unsupplemented formula-fed and 106.4 (SD 18.9) and 55.5 (SD 20.3) in the supplemented formula full-term infant group. No significant influence of the trace element contents of the formulas on the relative retention of Mn or Cu was found. 4. Young preterm infants, and to some degree young full-term infants, often had negative Mn balances caused by a high faecal excretion. The formulas with a Mn concentration below 100 micrograms/l gave a sufficient supply of Mn. Preterm infants fed on the unsupplemented formula had a marginal Cu supply and their first balances were negative (-3.8 (SD 1.8) micrograms/kg). 5. In accordance with the estimated safe and adequate daily dietary intakes (recommended dietary allowances), formula-fed infants receive much more Mn than breast-fed infants and their absolute retention is higher. 6. Cu from breast-milk had a significantly better biological availability than that from cow's milk formula. If retentions similar to those in breast-fed infants are intended, we conclude, therefore, that cow's milk formula should be fortified with Cu up to a level of at least 600 micrograms/l.

Animals↗