摘要:

SummaryThe plasma concentrations of 25-hydroxyvitamin D (OHD), 1,25-(OH)2D and 24,25-(OH)2D were determined in 28 healthy premature infants(median gestational age 33, range 28-36 wk; and median birth weight 1880, range 900-2350 g) during the first 5-10 wk of life,and in a reference group of 17 young adults. The infants received a vitamin D supplement of 500 IU/d and a diet low in calcium (Ca)and phophorus (P) compared with that of corresponding intrauterine accretion rates.The median 25-OHD concentration increased from 11 (range 6-30) ng/ml at 1 d to 27 (range, 15-41) ng/ml by 5-10 wk of age (P<0.01). 1,25-(OH)2D concentrations at age 1 d were similar to the adult levels (median 37, range 8-64 versus 35, range 18-58 pg/ml), but increased significantly within 1 wk to 48 (26-156) pg/ml (P=0.01), and between 1 and 3-4wk of age to 104 (58-203) pg/ml (P< 0.01). The levels at 5-10 wk were similar to the 3-4 wk value. 24,25-(OH)2D concentrations were persistently low compared with the adult levels (medians 0.4- 0.5, range <0.3-2.1 versus 1.7, range 0.4-2.0 ng/ml, P<0.01). The relative concentrations, expressed as the ratio of 24,25- (OH)2D to 25-OHD, were comparable to those of the adults at birth, but decreased significantly within 2 wk. The data demonstrate that healthypremature infants can produce high plasma levels of 1,25-(OH)2D.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummaryAutomated microanalytic chromogenic coagulation assays allow serial monitoring of critically ill newborn infants. In this study 84 premature infants [26 healthy prematures and 58 neonates with idiopathic respiratory distress syndrome (IRDS)] were studied daily during the first week of life, to investigate the possible significance of hemostatic abnormalities in IRDS.In neonates with IRDS, coagulation factors II and X, antithrombin III (AT-III), plasminogen, and α2-antiplasmin were significantly lower than control values. Recovery of the initially low AT-III levels was delayed relative to the other coagulation parameters measured. An AT-III<0.15 U/ml was present within the first 6 h of life in eight patients who developed IRDS, seven of whom died within 48 h. Autopsy of these neonates showed widespread fibrin deposition and hemorrhage in vital organs consistent with intravascular coagulation. These findings indicate that very low levels of AT-III are associated with disseminated intravascular coagulation in neonates with IRDS and suggest that a deficiency of AT-III is predictive of a poor outcome.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummaryGlucose turnover rates have been measured in conscious, chronically catheterized, non-pregnant and pregnant rabbits. Non-pregnant rabbits were studied weekly for 4 wk. Pregnant animals were studied once while non-pregnant and then weekly for up to 4 wk during pregnancy. Glucose turnover rate was measured using a primed-constant infusion of |U-14C]glucose and [6-3H]glucose.The weight of the rabbits did not vary throughout the 4-5 wk of study in either the non-pregnant or pregnant group. Seven pregnant rabbits delivered pups which weighed an average of 61 g each.In non-pregnant rabbits, blood glucose concentration did not vary with time. In the pregnant rabbits, blood glucose concentration fell by the end of gestation to an average value of 74.6 ± 2.7 mg/dl, significantly less (P<0.01) than the glucose concentration in the same animals before pregnancy, 88.2 ± 2.4 mg/dl.The weight specific glucose turnover rate did not vary with time in either the non-pregnant (4.38 ± 0.16 mg·min-1·kg-1) or pregnant rabbits (3.89 ± 0.29 mg· min-1·kg-1). Blood glucose clearance did not change over time in the non-pregnant rabbits but did increase in the pregnant rabbits in late pregnancy. Blood glucose clearance was inversely related to the fall in blood glucose concentration

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummaryComplement activity was compared in 50 low birth weight infants divided into appropriate and small for gestational age groups; the influence of birth weight and gestational age on complement development was also investigated. CH50and kinetics (tH50) of both classical and alternative pathway activity of complement, C3, and Factor B levels were significantly higher in small for gestational age infants (classical pathway CH50, 630 HU/ml ± 184 SD; CP tHjo, 77 min ± 47; aternative pathway CH50, 44.8 HU/ml ±11.3; AP tH50, 56 min ± 43; C3, 73.98 mg/dl ± 12.68; and Factor B, 13.17 mg/dl ± 3.67) than in weight-matched appropriate for gestational age infants (CP CH50, 523 HU/ml ± 152; CP tH50, 105 min ± 49; AP CH5o, 38.8 HU/ml ± 13; AP tHs50, 90 min ± 53; C3, 58.14 mg/dl + 9.43; and Factor B, 9.32 mg/dl ± 1.73). Complement values were lower in low birth weight infants than in adult controls (P<0.001 in all cases). All complement parameters were mainly correlated with gestational age; CH50values of the classical and alternative pathways were also highly correlated with each other (r= 0.64; P<0.001).Low birth weight infants, especially preterm infants, have an important defect of complement activity. Complement factors increase gradually during gestation and intrauterine growth retardation does not affect complement development. Classical and alternative complement pathway activities have a similar development pattern.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummaryWe compared the formation of14CO2from [I-14C]fatty acids in homogenates of cultured skin fibroblasts and white blood cells from 25 patients with adrenoleukodystrophy (ALD) and from 24 controls. The ALD group included 16 boys with childhood ALD, five men with adrenomyeloneuropathy (AMN), and two boys and two girls with neonatal ALD. The substrates were unbranched saturated fatty acids ranging in chain length from 16-26 carbons. From C24:0, the radioactive CO2 production by homogenates of ALD fibroblasts and white blood cells was 17% and 37% of control, respectively, and from C26:0 it was 17% of control in ALD fibroblasts. The CO2 evolution from palmitate (C16:0) in the ALD was identical to the control group; for C18:0, the value for ALD cells was 76% of control, and fatty acids with chain lengths between C18:O and C24:0 gave intermediate results. Results for childhood ALD patients were similar to those for the AMN patients. More limited studies with cultured amniocytes of fetuses with childhood ALD gave results similar to those obtained with cultured skin fibroblasts, and results with neonatal ALD patients appeared to be the same as for childhood ALD and AMN. Studies of three women who were carriers for childhood ALD gave values intermediate between ALD and control. The total C26:0 levels in ALD cultured skin fibroblasts and white blood cells were 4-6 times that of control; the total C24:0 levels were increased 10-30%, whereas the C22:0 levels were unchanged.The results suggest that ALD patients have a defect in the oxidation of very long chain fatty acids (C24:0 and longer) but not for the degradation of fatty acids with a chain length of 18 carbons or less. Such a defect could account for the accumulation of the very long chain fatty acids in a variety of tissues and lipid moieties. The accumulation of these fatty acids, coupled with the metabolic data presented here, suggests that normal catabolism of very long chain fatty acids involves a metabolic pathway which is distinct from that for other fatty acids, and that this pathway is genetically deficient in patients with ALD.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummaryThis study investigates the possibility of using pulsatile transcephalic impedance changes, ?Z, for the continuous monitoring of cerebral blood flow, CBF, in the sick newborn infant. The performance of the impedance method is compared with the measurement of cranial flow, Fc, using a strain gauge for detecting the predicted changes in cerebral blood flow when the baby breathes 2% CO2in air, or O2.In all five studies in which measurements were compared in air and CO2the expected increases in Fc and ?Z were seen. In six of seven studies comparing measurements in air and O2the expected fall in the variables was seen, indicating reduced cerebral blood flow. The problems of both these methods are discussed and we conclude that the impedance method is as good as the strain gauge method for detecting changes in cerebral blood flow.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummarySterile agar beads plus Pseudomonas aemginosa injected intratracheally produced local infection in rats, similar to that described for the injection of agar beads containing the same pathogen. It is suggested that it is not necessary for P. aemginosa to be inside the beads to induce lung infection.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

SummaryWe studied neutrophil microbicidal function and oxidative metabolic activity in a patient with glycogenosis Ib. The intracellular killing defect and the respiratory burst abnormality in gycogenosis Ib neutrophils were confirmed. The impaired oxygen-dependent microbicidal activity was shown to result from impaired hexose monophosphate shunt activity (impaired endogenous NADPH synthesis) and could be corrected by homogenization of the cells, followed by the addition of exogenous NADPH. Our data are thus consistent with a possible role for glucose-6-phosphate transport in neutrophil microbicidal function. We recommend a continuous prophylaxis with co-trimoxazole in patients with glycogen storage disease Ib.

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0031-3998    

出版商:OVID    

年代:1984

数据来源: OVID