Search PubMed⌕ Search

Biomedical subjects

L Stimmler

Publications and source records attributed to L Stimmler.

At least 19 recordsLinked to original sources
PubMed1993

Ganciclovir treatment of congenital cytomegalovirus infection: a report of two cases.

Ganciclovir has been shown to be effective against cytomegalovirus (CMV) in vitro, but its role in the treatment of congenital cytomegalovirus infection is unknown. We describe its use in the management of two cases of congenital CMV infections. The drug was well tolerated and virus shedding in the urine was eliminated, though hepatosplenomegaly and neurodevelopmental delay persisted in both cases.

Cytomegalovirus Infections↗
PubMed1990

Prediction of acute renal failure after birth asphyxia.

Twenty-one babies of 34-41 weeks' gestational age with birth asphyxia (5 minute Apgar score less than or equal to 5 or umbilical artery pH less than or equal to 7.2) were studied during the first two days of life to find out whether the urinary excretion of tubular markers of renal function is of value in the early diagnosis of acute renal failure. Urinary retinol binding protein, myoglobin, and N-acetyl-beta-D-glucosaminidase (NAG), expressed as a ratio with urinary creatinine, were measured and excretion profiles repeated at 3-6 days in 15 infants and at 7-14 days in 11 infants. Plasma creatinine concentration, creatinine clearance, plasma myoglobin concentration, and fractional sodium excretion were measured where possible in asphyxiated infants. Control data were obtained from 50 healthy infants: 28 gave urine samples alone, 17 urine and blood, and five blood alone. Normal urinary values were derived from 17, 25, and three infants, respectively, for the three time periods. The number of control samples was limited for ethical reasons. Four asphyxiated infants had acute renal failure (group 1), four had tubular dysfunction without glomerular disturbance (group 2) and 13 had normal renal function (group 3). Group 1 were clearly identified by greatly increased urinary retinol binding protein (greater than 27,000 micrograms/mmol creatinine) and myoglobin (greater than 1500 micrograms/mmol creatinine) excretion measured in the first two days of life. In control infants the range of excretion of retinol binding protein within the same time period was 3 to 967 micrograms/mmol creatinine and urinary myoglobin was undetectable. Excretion of NAG failed to discriminate between groups 1 and 2. Acute renal failure occurred only in infants who had heavy myoglobinaemia. Tubular dysfunction in group 2 was transient and not accompanied by plasma electrolyte disturbances. We conclude that measurement of urinary excretion of retinol binding protein or myoglobin after birth is helpful in the early diagnosis of acute renal failure.

Acetylglucosaminidase↗
PubMed1988

Mercury concentration in cord blood.

The mean mercury concentration measured in cord blood from 51 inner city babies born at Guy's Hospital was significantly higher (37 nmol/l v 20 nmol/l) than that from 17 babies born at the Royal Devon and Exeter Hospital, which serves a more rural population.

England↗
PubMed1988

Urinary creatinine excretion in the newborn.

We measured the excretion rate of endogenous creatinine in 84 24-hour urine collections obtained from 60 term and preterm newborn infants between the 3rd and the 68th postnatal day, at postconceptional ages 28-42 weeks. The rate was positively correlated with weight, height, and postconceptional age but not with postnatal age; the strongest correlation was that with weight. When the rate was factored by weight it was constant across the range of values studied, with a median and logarithmic mean value of 90 mumol/kg/day (10 mg/kg/day) and a range (2 log SD) of 45-180 mumol/kg/day (5-20 mg/kg/day).

Body Weight↗
PubMed1987

The effect of antenatal dexamethasone administration on glomerular filtration rate and renal sodium excretion in premature infants.

Creatinine clearance (Ccr) and renal sodium (Na+) excretion were measured in 10 premature infants (gestational age less than 34 weeks) whose mothers had received dexamethasone before delivery (group D) and in 11 whose mothers were not so treated (control, group C). Babies were studied twice: on days 2-5 (study 1. all infants) and days 6-10 (study 2, six infants in each group). In study 1, absolute and fractional Na+ excretion were significantly lower (P less than 0.01) and urinary K+:Na+ ratio significantly higher (P less than 0.025) in group D than in group C, while Cr did not differ between groups. In study 2, Ccr in group D had increased compared both with values obtained in the same babies in study 1 (P less than 0.05) and with group C babies in study 2 (P less than 0.05), but significant differences between groups in urinary Na+ excretion and urinary K+:Na+ ratio were no longer found. We conclude that exogenous glucocorticoids accelerate maturation of renal function in immature human infants, probably by inducing tubular Na+. K(+)-ATPase activity. Our findings support the view that endogenous glucocorticoid hormones may play an important part in the normal maturation process.

Adult↗
PubMed1984

Sodium homeostasis in term and preterm neonates. III. Effect of salt supplementation.

Clinical and biochemical effects of supplementing dietary sodium intake to 4 to 5 mmol(mEq)/kg/day from days 4 to 14 of life were studied in 22 infants of gestational age 27 to 34 weeks. These infants were compared with a group of 24 unsupplemented babies. Supplemented infants lost less weight postnatally and regained birthweight more quickly: their improved weight gain continued after supplementation was stopped. Sodium balance was positive at age 5 to 11 days in supplemented babies but slightly negative in controls. Potassium balance was more strongly positive in the supplemented group. Plasma sodium concentration was higher in supplemented infants during weeks 3 and 4. Hyponatraemia was significantly more common in unsupplemented (37.5%) than supplemented (13.6%) infants. No infant became oedematous, hypernatraemic, or showed evidence of circulatory overload. The incidence of patent ductus arteriosus and necrotising enterocolitis was not increased; no intracranial haemorrhages occurred. Urinary potassium:sodium ratio was lower in supplemented babies than controls suggesting responsiveness of the distal tubule to mineralocorticoids. Providing 4 to 5 mmol(mEq)/kg/day of sodium to infants born before 34 weeks' gestation for the first two postnatal weeks improves growth and biochemical status and causes no undesirable side effects.

Body Weight↗
PubMed1983

Sodium homeostasis in term and preterm neonates. I. Renal aspects.

Eighty five 24 hour sodium balance studies and creatinine clearance measurements were performed in 70 infants of gestational age 27-40 weeks and postnatal age 3-68 days. The kidney's capacity to regulate sodium excretion was a function of conceptional age (the sum of gestational age and postnatal age) and an independent effect of postnatal age was also observed--extrauterine existence increased the maturation of this function. The sodium balance was negative in 100% of infants of less than 30 weeks' gestation, in 70% at 30-32 weeks, in 46% at 33-35 weeks, and in 0% of greater than 36 weeks, and the incidence of hyponatraemia closely paralleled that of negative sodium balance. Despite a low glomerular filtration rate (GFR) urinary sodium losses were highest in the most immature babies but fractional sodium excretion (FENa) was exponentially related to gestational age. An independent effect of postnatal age could be identified on FENa but not in GFR. These findings indicate that in infants of greater than 33 weeks' gestation sodium conservation is possible because of a favourable balance between the GFR and tubular sodium reabsorption, but that below this age GFR exceeds the limited tubular sodium reabsorption capacity. The rapid increase in sodium reabsorption in the first few postnatal days seems to be due to maturation of distal tubular function, probably mediated by aldosterone. We suggest that the glomerulotubular imbalance for sodium is a consequence of the immaturity of the tubuloglomerular feedback mechanism, and we estimate that the minimum sodium requirement during the first 2 weeks of extrauterine life is 5 mmol (mEq)/kg/day for infants of less than 30 weeks' gestation and 4 mmol (mEq)/kg/day for those born between 30 and 35 weeks.

Aging↗
PubMed1983

Sodium homeostasis in term and preterm neonates. II. Gastrointestinal aspects.

Eighty five 24 hour balance studies were performed on 70 healthy newborn infants of gestational age 27-40 weeks; dietary intake and stool losses of sodium were measured. There was a relation between gastrointestinal sodium absorption and conceptional age (the sum of gestational and postnatal age), whether expressed as absolute stool sodium losses or as the ratio of stool sodium to dietary sodium intake. The stool K:Na ratio rose appreciably with maturation, although stool content of potassium was not greatly increased. These findings suggest that intestinal sodium absorption is inefficient in immature babies and that the degree of malabsorption is inversely related to conceptional age.

Aging↗
PubMed1982

Plasma vitamin K1 in mothers and their newborn babies.

Plasma vitamin K1 (phylloquinone) was assayed in normal adults and pregnant women at term and their babies by a method based on high-performance liquid chromatography. The mean plasma concentration in 30 healthy, fasting adults was 0.26 ng/ml (range 0.10-0.66). 8 out of 9 healthy mothers at term had a mean K1 concentration of 0.20 ng/ml (range 0.13-0.29), but K1 was not detected in the cord plasma of their babies. 1 mg vitamin K1 given intravenously to 6 mothers shortly before delivery raised their plasma K1 to 45-93 ng/ml: K1 was then detectable in the cord plasma of 4 of the 6 infants but at a much lower concentration which did not exceed 0.14 ng/ml. The large concentration gradient between maternal and neonatal plasma suggests that vitamin K1 does not cross the placenta readily or that the uptake by fetal plasma is low, perhaps because of low levels of a binding lipoprotein. The low levels of vitamin K in the cord plasma of the normal newborn would explain "physiological" hypoprothrombinaemia and suggest the need to reassess current clinical practice in respect of vitamin K prophylaxis in the early neonatal period.

Adult↗
PubMed1977

Hyperlipidaemia in children on regular haemodialysis.

Fasting plasma concentrations of triglycerides (TG), cholesterol, immunoreactive insulin (IRI), and blood glucose were raised in 16 children with chronic renal failure on regular haemodialysis compared with 18 healthy children. In the patients plasma IRI correlated positively with plasma TG, while blood glucose did not correlate with IRI or lipid concentrations. Dietary intake, expressed as percentage of recommended intake for height-age, did not correlate with plasma lipids, but there was a positive correlation between plasma TG and the proportion of calories derived from carbohydrate. The children were not malnourished as evidenced by normal plasma albumin and transferrin concentrations. The mechanism of the hyperlipidaemia is unclear but it may be related to the glucose intolerance with hyperinsulinaemia which is found in uraemia. In view of the risk of premature atherosclerosis, plasma lipid concentrations should be monitored in children with chronic renal failure and attempts made to ameliorate hyperlipidaemia with appropriate dietary manipulations.

Adolescent↗
PubMed1975

Diurnal variation in the effects of insulin on blood glucose, plasma non-esterified fatty acids and growth hormone.

Insulin 0.05 mu/kg body weight was injected intravenously into 14 subjects both at 8 a.m. and 5 p.m. in random order 12 hrs after a 50 g glucose meal. Fasting glucose levels were similar in both cases but the 48percent plus or minus 10 percent fall in blood glucose in the morning was significantly greater (p smaller than 0.001) than that of 34 percent plus or minus 7 percent in the afternoon. Fasting plasma NEFA, however, varied markedly between 477 plus or minus 150 muEqlL in tth morning and 725 plus or minus 195 muEqlL in the afternoon (p smaller than 0.001) and the fall after insulin injection (64 percent plus or minus 14 percent) was greater in the afternoon than in the morning (47 percent plus or minus 15 percent) (p smaller than 0.001). There was an inverse relationship between proportional glucose disappearance and proportional NEFA disappearance (p smaller than 0.001). The calculated caloric change in plasma, the sum of the falls in glucose and NEFA, were very similar in both morning (2.2 plus or minus 0.5 Cals/1) and afternoon (2.3 plus or minus 0.5 Cals/1), i.e., in spite of the variations of glucose and NEFA metabolism produced by insulin at different times, the nett effect, in terms of energy, was the same. Plasma growth hormone response in the afternoon was found to be enhanced compared with the morning values, although the degree of hypoglycaemia was greater in the morning.

Adult↗
PubMed1975

Relation between changes in plasma calcium in first week of life and renal function.

(1) Of 71 infants fed on reconstituted dried or evaporated cow's milk, 31 showed a fall in plasma calcium between the 1st and 6th days of life, whereas in 35 breast-fed infants this occurred in only 5. (2) Those artificially-fed infants who had shown a rise in plasma calcium over this period had significantly lower plasma creatinine values and significantly higher excretion of creatinine than those infants who showed a fall in calcium levels. (3) Artificially-fed infants who had shown a rise in calcium had significantly lower plasma osmolality and significantly higher osmolar excretion in the urine than those infants who showed a fall in plasma calcium. (4) It is suggested that a delay in the normal increase in glomerular filtration rate during the first week of life in some infants leads to phosphate retention. This, together with a higher dietary intake of phosphate, leads to a decrease of the plasma calcium to hypocalcaemic levels.

Animals↗
PubMed1974

Diurnal variation in glucose tolerance: associated changes in plasma insulin, growth hormone, and non-esterified fatty acids.

Oral glucose tolerance tests were performed in the morning and afternoon of separate days on 31 people derived from a normal population sample. Blood sugar levels were higher in the afternoon test from and including 60 minutes after the glucose load. The degree of diurnal variation was similar in men and women, but greater in the older half of the group. It was negatively correlated with the degree of obesity. The plasma insulin response was less at the 30 minute time point in the afternoon, but significantly exceeded the morning values at 120 and 150 minutes after the glucose load. Growth hormone levels were similar in morning and afternoon tests. Fasting non-esterified fatty acid levels were significantly higher before the afternoon test.The relatively impaired glucose tolerance in the afternoon is associated with a delayed insulin response to the glucose load. This seems unlikely to be the sole explanation, however, and increased non-esterified fatty acid metabolism with a consequent decrease in glucose disposal may also contribute.

Adult↗
PubMed1974

Diurnal variation in response to intravenous glucose.

Intravenous glucose tolerance tests (25 g) were performed in the morning and afternoon on 13 apparently normal persons. The individual K values (rate of decline of blood sugar) were all higher in the morning tests, and the mean values were significantly higher in the morning. Fasting blood sugar levels were slightly lower in the afternoon. There was no difference between the fasting morning and afternoon plasma insulin levels, but the levels after glucose were lower in the afternoon. Growth hormone levels were low at all times in non-apprehensive subjects and unaffected by glucose. The results suggest that the impaired afternoon intravenous glucose tolerance, like oral glucose tolerance, is associated with impaired insulin release and insulin resistance.

Adult↗