ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryThe frequency of gram-negative infections and endotoxemia in the perinatal period prompted an investigation of the effects of endotoxin (Escherichia coli026B6) on hepatic drug metabolism. Gravid female rats given injections IP with different dosages of lipopolysaccharide during late pregnancy resulted in significant depression of the liver microsomal cytochrome P-450 dependent monooxygenase activities. The acute administration of endotoxin to mothers (1.4 mg/kg on seventh day after parturition) significantly decreased the hepatic activity of aminopyrine demethylase and contents of cytochrome P-450 of suckling neonates and mothers. However, chronic administration of endotoxin (0.2 mg/kg/ day for 7 days) to lactating mothers did not alter neonatal enzyme activities. When neonates themselves were given injections of endotoxin (1.0 mg/kg) at 7, 16, and 27 days of age, a significant reduction in levels of mixed function oxidase enzymes was observed. These observations suggest that the ability of mothers and neonates to metabolize drugs is significantly decreased upon exposure to endotoxin, and this demands careful evaluation of drug disposition studies in gram-negative sepsis.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryNine lysosomal enzyme activities were examined in granulocytes and lymphocytes from two unrelated patients with Chediak-Higashi syndrome (CHS) in “accelerated phase” and from their family members. In CHS granulocytes, there was a marked reduction of α-mannosidase (E.C. 3.2.1.24), α-galactosidase (E.C. 3.2.1.22), and α-fucosidase (E.C. 3.2.1.51) activities, which were below 21, 24, and 43% of mean control values, respectively. In CHS lymphocytes, β-glucuronidase (E.C. 3.2.1.31) and α-mannosidase activities were also decreased.In granulocytes of family members, the activities of acid phosphatase (E.C. 3.1.3.2),N-acetyl-β-glucosaminidase (E.C. 3.2.1.30), aryl sulphatase (E.C. 3.1.6.1), and β-glucuronidase were significantly higher than the control values (P< 0.001), which were 262, 218, 414, and 180% of mean control values.Neither the inhibitor in CHS granulocytes nor the activator in the heterozygous granulocytes to those enzymes could be found by mixing experiments with normal ones.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryPlasma hypoxanthine (HX) concentrations were measured in 16 acutely exteriorized fetal lambs during induced, graded hypoxia, and the values found were compared to established indicators of poor oxygenation in the fetus, such as oxygen saturation, blood gases, pH, base excess, and lactate. Highly significant correlations were found to all parameters of hypoxia except PaO2. When the duration of hypoxia was taken into account, the HX concentrations showed highly significant correlation to constructed variables of oxygen debt. In multiple correlation analysis, pH turned out as the strongest single variable, explaining 80% of the variance in HX concentration with the remaining parameters increasing the value to 87%. The highest concentrations of HX were obtained when hypoxemia was combined with acidemia or with a large fetomaternal PaCO2-gradient which correlated to a reduced cardiac output in the fetus. These findings appear to corroborate the conclusion that plasma HX concentration reflects tissue hypoxia in the fetal lamb.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryTranscutaneous oxygen tension (tcPO2) was continuously monitored, and behavioral state was evaluated in a group of 10 normal preterm infants and 10 normal term infants. In the preterm infant group, birth weight was 1505 ± 154 g, gestational age was 32.3 ± 2.3 wk, and postnatal age was 8.4 ± 5.1 days (mean ± S.D.). In the term infant group, birth weight was 3245 ± 247 g, gestational age was 39.9 ± 0.3 wk, and postnatal age was 6.3 ± 3.4 days (mean ± S.D.).A mean tcPO2level for each behavioral state in each infant was calculated, and a paired comparison between all states was made. In the preterm and term infant groups, mean tcPO2levels were higher in state 1 (“quiet sleep”), state 4 (“active awake state”), and state 5 (“crying”) than during state 2 (“active sleep”). The difference (ΔtcPO2) was significant (P< 0.05). In the preterm infant group, mean tcPO2level in state 2 was 62.9 ± 17.1 mm Hg (mean ± S.D.). Mean ΔtcPO2in state 1 was +5.4 mm Hg (range, −0.9 to +9.2 mm Hg), mean ΔtcPO2in state 4 was +6.8 mm Hg (range, +0.6 to +20.2 mm Hg), and in state 5 was +9.9 mm Hg (range, +5.1 to +17.5 mm Hg). In the term infant group, mean tcPO2level in state 2 was 64.5 ± 9.6 mm Hg (mean ± S.D.). Mean ΔtcPO2in state 1 was +5.8 mm Hg (range, −1.2 to +11.0 mm Hg), mean ΔtcPO2in state 4 was +8.1 mm Hg (range, +2.2 to +32.3 mm Hg), and mean ΔtcPO2in state 5 was +7.3 mm Hg (range, −1.6 to +26.5 mm Hg). There was insufficient data to evaluate tcPO2levels during state 3 (“quiet awake state”). In the term infant group, the effect of bottle feeding on tcPO2was also assessed. Gross alterations in tcPO2during bottle feeding were not observed, and mean tcPO2levels during bottle feeding (76.1 ± 8.5 mm Hg; mean ± S.D.) were not significantly different from mean tcPO2levels found during states 1, 4, and 5.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryThe phosphatidylcholine (PC) content (mg/g dry lung weight; mean ± S.E.) of lung washes of 1 to 3-day-old rabbits was significantly greater 30 min after the injection of the muscarinic agonist oxotremorine (0.2 mg/kg; 50.5 ± 2.9 mg/g; 2P< 0.01) or epinephrine (50 μg/kg; 78.0 ± 14.8 mg/g; 2P< 0.001) than saline (25.7 ±1.9 mg/g). Injection of atropine (2 mg/kg), dl-propranolol (1 mg/kg) but not d-propranolol (1 mg/kg) at 40 min or adrenalectomy at 45 min before killing abolished the increase produced by oxotremorine (2P< 0.001). Also, dl-propranolol antagonized the increase produced by epinephrine. Palmitic and myristic acids were the major fatty acids in the lung wash PC of control and oxotremorine-treated rabbits. The residual lung tissue PC content following atropine (2 mg/kg; 104.4 ± 18.5 mg/g) was significantly greater (2P< 0.05) than following saline (72.6 ± 6.0 mg/g) but not different (2P< 0.05) in other treatment groups. The total lung content of PC was 55% greater (2P< 0.001) than controls 30 min after epinephrine (50 μg/kg).The surface activity of lung washes (mg/g dry lung weight; mean ± S.E.), assayed on a surface tension balance using dipalmitoyl-phosphatidylcholine as standard, was significantly greater (2P< 0.05) 30 min following injection of oxotremorine (0.2 mg/kg; 73.8 ± 9.9 mg/g) or epinephrine (50 μg/kg; 72.2 ± 10.2 mg/g) than saline (42.8 ± 2.0 mg/g). Ten-min infusions of oxotremorine (0.34 μg/ml) into isolated, ventilated, perfused neonatal rabbit lung preparations failed to alter the PC content of the subsequent wash, but this was significantly (2P< 0.05) raised from 3.7 (± 0.8) to 4.8 (± 0.8) mg/g dry lung wt by a 10 min infusion of epinephrine (3.4 μg/ml).

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummarySerum putrescine (Pu), spermidine (Sd), spermine (Sp), and plasma diamine oxidase activity (DAO) were determined in cystic fibrosis (CF) homozygotes and heterozygotes plus age-matched controls. Mean (±S.E.) levels of Pu (0.51 ± 0.06 nmoles/ml), Sd (0.63 ± 0.07nmoles/ml), and Sp (0.33 ± 0.08 nmoles/ml) were higher (P< 0.001) in 17 control childrenversus16 healthy adults (Pu = 0.15 ± 0.04; Sd = 0.14 ± 0.03; Sp = 0 in all). All 4 CF adults tested, but only 3 of 24 CF children, had increased polyamines relative to age-matched controls. Pu (0.33 ± 0.04), Sd (0.33 ± 0.05) and Sp (0.16 ± 0.12) were increased (P< 0.001) in 11 adult heterozygotes; in turn, Pu (0.56 ± 0.11;P< 0.025) and Sd (0.86 ± 0.22;P< 0.005) were higher in the adult CF patients than in the heterozygotes. Plasma DAO was higher (P< 0.001) in 45 control children (9.3 ± 0.7 units/ml)versus61 healthy adults (5.7 ± 0.07). Levels ≥ +2 S.D. for controls occurred in 8 (21%) of 39 CF patients. Plasma DAO (19 ± 4.8) was increased (P< 0.001) in 27 adult heterozygotes; 10 (37%) had values ≥ +2 S.D. for normal adults. One or more polyamines and/or DAO were increased in each of 11 heterozygotes in whom all parameters were measured. These composite abnormalities might be considered as a potential means for identification of asymptomatic CF heterozygotes.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryThe age-related changes in fasting arterial levels of energy substrates and insulin were studied at birth and/or 6 wk in eleven baboon infants. In addition, the renal contribution to glucose release in the primate infant was estimated. Arterial blood glucose levels were similar in six fasted newborns and in nine fasted 6-wk-old infants. Arterial blood lactate, alanine, pyruvate, glutamate, and glutamine levels were significantly higher (P< 0.01) in the new born animals, and β-hydroxybutyrate was significantly higher in the older animals (P< 0.001). Arterial plasma insulin levels were low in both groups. Levels of blood glucose in the inferior vena cava below the renal vein were significantly lower than levels in the aorta (P< 0.01). In contrast, levels of blood glucose in the inferior vena cava above the renal vein were significantly higher than in the aorta (P< 0.05). Computed renal vein glucose levels were higher than those in the aorta (P< 0.01). In the newborn infants, there was significant renal uptake of lactate, pyruvate, glycerol, and glutamine (P< 0.01), and release of β-hydroxybutyrate (P< 0.05). In the older animals, there was renal uptake of alanine, lactate, pyruvate, and glycerol (P0.01). Mean cardiac output per kg body weight did not differ significantly in the newborn and 6-wk-old infants.Lactate uptake was potentially responsible for 59% of mean renal glucose output in the newborn and 76% of mean renal glucose output in the older infant. Net renal glucose release in eight 6-wk-old infants was estimated to be 3.5 ± 1.1 μM/min · kg (95% confidence limits, 0.7 < 3.5 < 6.2). Net renal glucose release in three newborn infants was 4.7, 5.4, and 19.8 μM/min · kg. There was a significant linear relationship between arterial lactate levels and renal glucose production in the older infants (P< 0.05). Extremely low arterial pH was associated with increased renal glucose release in the newborn, and high arterial pH with decreased or absent glucose release in the 6-wk-old animals.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

SummaryGlycine transport in both normal and nonketotic hyperglycinemia fibroblasts was shown to occur by a sodium-dependent system. No significant difference could be detected in either the Km's (1.4 to 2.0 mM) or the Vmax's (6.2 to 16 nmole per mg protein per min) of the three control and three patient cell lines. Valine was a weak competitive inhibitor of glycine uptake. Kis from both groups fell into the 5.6 to 5.8 mM range. Plasma levels of valine of one patient reached a maximum of 0.6 mM following a valine load. Glycine cleavage activity could not be detected in either control or nonketotic hyperglycinemia fibroblast lines. Serine utilization was the same in both nonketotic hyperglycinemia and control lines.

ISSN:0031-3998    

出版商:OVID    

年代:1980

数据来源: OVID