摘要:

SummaryThe relationship between breath hydrogen excretion and intestinal ischemia was investigated in nine mechanically ventilated dogs under pentobarbital anesthesia. An ileal segment was isolatedin situ, ligated at each end, and insufflated with hydrogen. Expired air was collected at intervals. Blood volume was reduced 30% by three successive equivalent hemorrhages 10 min apart. Local bowel ischemia was produced by clamping the blood supply to the isolated segment for 10 min. Graded hemorrhage produced stepwise reductions in breath hydrogen concentration, to 77 ± 13, 66 ± 15, and 35 ± 8% (mean ± S.E.) of baseline after the first, second, and third hemorrhages, respectively. These reductions correlated highly (r= 0.84;P< 0.01) with declines in mean aortic blood pressure. Occlusion of blood supply caused a significant (P< 0.025) decrease in breath hydrogen concentration and excretion to 39 ± 14% of baseline. Termination of occlusion was followed within 2 min by a 7-fold increase in breath H2concentration above the original baseline, probably reflecting reactive hyperemia. Breath hydrogen measurements appear to reflect functional (hemorrhagic shock-induced) and mechanical (vascular occlusion induced) enteric ischemia in dogs.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryWe prospectively evaluated concentrations of β-D-galactosidase, α-L-fucosidase, β-D-N-acetylglucosaminidase, and lysozyme in urine from normal subjects, ambulatory patients with cystic fibrosis (CF), and CF patients with previously normal renal function who were receiving intravenous aminoglycoside (AG) therapy-Enzyme activities were generally low or negligible in subjects not receiving AG. Enzymuria was documented during 12 of 13 AG treatment courses and most frequently involved β-D-N-acetylglucosaminidase excretion. In nine courses, enzymuria occurred in the absence of proteinuria or elevations of blood urea nitrogen and serum creatinine. In three courses attended by enzymuria and evidence of nephrotoxicity, neither the time of appearance nor the magnitude of enzymuria was different from that of nonnephrotoxic patients. In two of these three treatment courses, enzymuria preceded clinical evidence of nephrotoxicity by 16 and 5 days, and in the third course enzymuria and elevation of blood urea nitrogen and serum creatinine occurred simultaneously. We conclude that enzymuria is not a reliable predictor of nephrotoxicity due to AG in CF patients and is not an indication to discontinue AG therapy.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryThirty-one premature infants who required nasojejunal feeding were evaluated for pancreatic exocrine function before and after feeding of milk-based or soy-based formulas for 30 days. The two groups were well matched for age and birth weight (about 1.5 kg). At birth, all infants had high basal secretion of trypsin and chymotrypsin, but low lipase and no amylase activity. Additionally, there was no response to pancreozymin (CCK). After 30 days of feeding with either soy or milk-based formulas, both groups showed a similar increase in body weight (to 1.8 kg) and basal secretion of trypsin, chymotrypsin, and lipase and failure to secrete amylase. The group that was fed milk-based formula failed to respond to CCK and secretin administration. Thus, soy- and milk-based formulas result in similar weight gain and similar basal pancreatic enzyme secretion while feeding with soy-based formula selectively increases the trypsin and lipase response to CCK.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryMale infants have a higher risk of respiratory distress syndrome than females at concurrent gestations. Recent evidence in humans has linked fetal sex with differences in amniotic fluid indices of lung maturation. We tested the hypothesis that the late gestation surge in pulmonary surfactant production occurs later in the male fetus than in the female fetus in the rabbit model. We measured saturated phosphatidylcholine and total phosphatidylcholine in lung lavage at 26, 28, and 30 days gestation and in amniotic fluid at 24, 26, 28, and 30 days gestation (term = 31 days). The saturated phosphatidylcholine/sphingomyelin ratios were 158 and 55% higher in female fetal lung lavage at 26 and 28 days, respectively, and 75% higher in amniotic fluid at 28 days (P< 0.05). The total phosphatidylcholine/sphingomyelin ratios were 39% higher in female fetal lung lavage and 35% higher in female amniotic fluid at 28 days (P< 0.05). Significant differences were not detected in the very immature (24 day) or the mature (30 day) fetuses. This provides clear evidence of a biochemical difference according to fetal sex in the maturation of pulmonary surfactant production.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryThe developmental pattern of regional glomerular density and glomerular perfusion rate (GPR) was studied in 20 chronically catheterized fetal lambs between 106 and 140 days of gestation (term, 145 days) and in six newborn lambs between 3 and 19 days of age. The present study demonstrates for the first time in lambs that the nephrogenic zone disappears around 130 days of gestation and that the total glomerular counts per kidney in fetuses over 130 days (468296 ± 41173 glomeruli per kidney) is not significantly different than in newborn lambs (433704 ± 21553). Glomerular density, determined in four cortical zones (zone I being the outermost portion of the cortex) did not show any significant changes during fetal life; however, significant decreases in glomerular density were observed in each cortical zone after birth. The relative distribution of glomeruli during fetal life decreased in the outer portion (zones I and II) and increased in the inner portion (zones III and IV) of the cortex as fetuses matured and approached term. After birth, this difference became even more prominent; the outer cortical fraction (zone I) decreased from 49.6 ± 2.9% in fetuses of less than 120 days to 37.8 ± 1.5% (P< 0.05) in newborn lambs, whereas the fraction found in zone III increased from 14.9 ± 1.3% to 20.8 ± 0.7% (P< 0.05). Small but significant increases in glomerular filtration rate (GFR) (P< 0.01) and total renal blood flow (P< 0.05) were observed during fetal life: GFR and total renal blood flow increased, respectively, from 1.84 ± 0.11 and 37 ± 2 ml/min in fetuses <120 days to 3.05 ± 0.2 and 46 ± 4 ml/min in fetuses >130 days gestation. During the same period, filtration fraction (FF) did not increase significantly whereas a significant (P< 0.01) 58% increase in FF was observed after birth: FF increased from 10.16 ± 0.74% in fetuses >130 days gestation to 16.12 ± 1.66% in newborn lambs. Renal vascular resistance decreased from 1.03 ± 0.08 mm Hgml-1min-1in fetuses >130 days to 0.51 ± 0.05 mm Hgml-1min-1(P< 0.01) in newborn lambs. Glomerular perfusion rate (GPR), computed for each cortical zone did not change significantly during the last trimester of gestation. After birth, GPR increased almost three times in zones I and II (from 69.2 ± 8.9 and 53.6 ± 4.2 nl/min in fetuses >130 days to 206.9 ± 16.8 and 161.3 ± 20.7 nl/min in newborn lambs, respectively), doubled in zone III (from 55.6 ± 10 nl/min in fetuses >130 days to 119.5 ± 8.9 nl/min in newborn lambs) and remained unchanged in zone IV when compared to fetal GPR values. After birth, the increase in GFR correlated closely with the GPR increase in zone I (r = 0.87) and zone II (r = 0.87), suggesting that the developmental pattern of GFR after birth may depend on the increase in GPR in the outer zones of the renal cortex.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummarySix immature infants were given oral feedings of 10% preservative-free human immune serum globulin ranging from 1 to 8 ml/kg/day. A seventh infant served as a control. Undigested and partially digested IgG was detected in the stools in significant quantities in all but the control infant. This coproantibody retained significant opsonic activity for type III group B streptococci as determined by a chemiluminescence assay, but lost most of its tetanus antibody activity. The newborn infants' enzymatic immaturity or rapid transit time permits the passage of intact IgG or partially digested IgG to pass throughout the gastrointestinal tract.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryThese studies were implemented to assess the relationship between fetal vasopressin secretion and the progression of parturition as well as the contribution of specific stimuli to vasopressin release during labor. In chronically catheterized fetal lamb preparations, labor was induced by infusion of adrenocorticotropin (12.5 mg/kg/hr) to seven fetuses at 130 ± 1 day of gestation. Before labor, fetal plasma vasopressin concentrations were 2.1 ± 1.4 pg/ml and remained low (5.3 ± 3.4 pg/ml) during prodromal and early phases of labor, but rose significantly in the active and expulsive phases (39.6 ± 27.5 and 173.3 ± 152.9 pg/ml) to reach peak values at delivery (584.2 ± 433 pg/ml) and decrease by 30 min after birth (359.8 ± 90.0 pg/ml).At delivery, fetal plasma vasopressin concentrations were strongly correlated (P< 0.001) with hormone values obtained during the latter phases of labor. Fetal arterial pH and oxygen tension was inversely correlated with plasma vasopressin (P< 0.01). No similar correlations were found with arterial PCO2, K, Na, Cl, osmolality, or packed cell volume. Unexpectedly, we observed a significant (P< 0.001) and progressive decrease in fetal oxygen tension during the induction process. Other characteristics of adrenocorticotropin-induced parturition seemed to mimic those of spontaneous labor.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryThe aim of this study was to compare the E rosette-forming cells and nonspecific alpha naphtyl esterase (ANAE)-positive lymphocyte values in normal and pathologic situations. In newborns, the ANAE-positive lymphocytes represented less than 60% of the E rosette population. During the first year of life, E rosette-forming cells (E-RFC) reached normal values as soon as one month whereas only three-fourths of the T cells exhibited an ANAE-positive staining. In adult T cell populations, nearly 90% were ANAE-positive. Our observations of immune deficiencies suggested that the relative proportions of E-RFC and ANAE-positive lymphocytes were generally comparable to normal values. However, in the majority of the patients with very low or absent E-RFC (severe combined immune deficiencies, Di George syndrome, and congenital rubella), some ANAE-positive lymphocytes could be detected. Our immunologic survey shows that the ANAE-positive lymphotytes were in a normal range 2 years after a bone marrow transplantation in severe combined immune deficiencies patients. One child who exhibited a normal amount of E-RFC and whose lymphocytes failed to respondin vitroto mitogens had practically no ANAE-positive lymphocytes. An elevated amount of ANAE-positive cells in juvenile rheumatoid arthritis may reflect an augmentation of the T helper functions which permanently stimulatedin vivoimmunoglobulin production.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SummaryNeonatal polymorphonuclear leukocytes (PMNs) have previously been shown to be chemotactically deficient. To probe the mechanism(s) responsible for this deficiency, we have investigated the phenomenon of concanavalin A-induced capping in neonatal PMNs. PMNs from cord blood of 17 healthy, full-term infants and 17 normal adult volunteers were isolated by standard Ficoll-Hypaque and dextran sedimentation. After incubation with and without colchicine, the cells were reincubated with fluorescein isothiocyanate-Con A, fixed, and prepared in wet mounts. Using a fluorescence microscope, PMNs were identified, and the percentage of the capped cells was counted.Upon treatment with colchicine, adult PMNs showed a significant increase in the percentage of capped cells. By contrast, the cord blood PMNs showed no significant increase in capping after colchicine treatment. The difference between percentage of PMNs showing colchicine-induced capping in adult and cord blood was highly significant (P< 0.01; Student'sttest).

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

Summary17β-Estradiol (0.44 to 4.4 μg/kg) was intramuscularly administered to pregnant rabbits on day 25 or 26 of gestation, and the fetuses were delivered by cesarean section 24 hr later. On light microscopy, the lungs from the treated group had larger alveoli and thinner interalveolar septa than did those from the controls at the same gestational age. The lumen:septa ratio was 0.62 ± 0.06 in the control group and 0.88 ± 0.05 in the treated group (P< 0.01). Blood vessels in the lungs of the treated group were also more mature than were those in the control group. Alveolar epithelial cells consisted of 52% undifferentiated, 21% type II, and 27% type I cells in the control group. In the estrogen-treated group, the corresponding distribution was 25, 29, and 45%. There were 0.82 ± 0.16 lamellar bodies per alveolar cell in the treated group compared to 0.38 ± 0.06 in the controls (P< 0.05). Estrogen decreased fetal lung glycogen content from 247 ± 15 μg/mg protein to 70 ± 9 on day 26 and from 103 ± 13 to 13 ± 2 on day 27 (P< 0.001). Estrogen administration increased the rate of incorporation of choline into phosphatidylcholine in fetal lung slices, decreased the rate of thymidine incorporation into DNA, but had no effect on the rates of incorporation of ethanolamine into phosphatidylethanolamine or of leucine into protein. These data indicate that estrogen accelerates the rate of fetal lung maturation. It appears to stimulate lung differentiation at the expense of lung growth.

ISSN:0031-3998    

出版商:OVID    

年代:1981

数据来源: OVID