ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

This study examined whether insulin-like growth factor-I (IGF-I) bound to specific functioning IGF receptors on the surface of Caco-2 cells and how this binding was affected by the differentiation and polarity of these cells. IGF-I, which increased cell proliferation in a dose-dependent manner, bound to a specific receptor on the surface of Caco-2 cells. Affinity cross-linking with labeled IGF-I followed by reducing sodium dodecylsul-fate-polyacrylamide gel electrophoresis (SDS-PAGE) showedMrs at 135,000, 270,000 and 355,000 bands, which was inhibited by unlabeled IGF-I. A Scatchard analysis of radioligand-receptor binding showed the presence of a single class of receptors with high affinity for IGF-I. This class of receptors was specific for IGF-I, the affinity of IGF-I to the receptor being four and 150 times greater than IGF-II and insulin, respectively. There was no difference in the affinity of IGF-I to type 1 IGF receptors between less-differentiated [dissociation constant (Kd) = 3.81 nM] and well-differentiated cells (Kd= 3.78 nM); however, well-differentiated cells showed a 2.4-fold higher maximum number of binding sites (Bmax) than less-differentiated cells (3.45 vs. 1.44 x 104sites/cell), indicating an increase in the density of IGF-I receptors with differentiation. Furthermore, the number of type 1 IGF receptors on the basolateral surface of well-differentiated cells was 2.4 times greater than that seen on the apical surface. In summary, IGF-I binds to a single class of specific Caco-2 cell-surface receptors, which increase in number with differentiation and are found on both aspects of the epithelium.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Human milk fed to very-low-birth-weight infants must be fortified with protein, minerals, and vitamins. We tested a new fortification regimen in which the amount of fortifier was adjusted on the basis of frequent determinations of serum urea nitrogen (SUN). A newly formulated fortifier based on bovine milk proteins was employed either in the new fashion (regimen ADJ) or in the conventional fixed proportion (regimen FIX). Using the fixed proportion, the study also compared the new fortifier with a fortifier based on human milk protein (regimen HMP). Twelve infants were studied with each of the three regimens; nearly all completed 3 weeks of study. Protein intake was generally higher in ADJ than FIX; the difference was significant (p < 0.01) during week 2. Weight gain was somewhat (but not significantly) greater in regimen ADJ (32.3 g/d or 18.8 g/kg/d) than in regimen FIX (30.0 g/d or 18.3 g/kg/d). SUN was higher in ADJ than in FIX, and several other serum chemical values (calcium, phosphorus, potassium) tended to be higher, probably reflecting higher intakes of these nutrients with ADJ than with FIX. Plasma concentrations of several amino acids were higher in ADJ than FIX, but none, including threonine, were outside the physiological range. In comparing regimen FIX to regimen HMP, infants on FIX received similar intakes of protein and showed slightly but not significantly more rapid weight gain. Concentrations of SUN were lower with FIX, but other serum chemical values, including amino acids, were generally similar to HMP. We conclude that use of the new adjustable fortification regimen is feasible and safe and that it should be studied further. It produced the expected increases in nutrient intakes and growth. The new bovine milk-based fortifier appears to be equivalent to the human milk-based fortifier.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Severe and protracted diarrhea (SPD) is the most severe form of diarrhea in infancy and has also been defined as intractable diarrhea. Its etiology is poorly defined. We have retrospectively evaluated the etiology, the outcome, and the risk factors of 38 children, admitted with protracted diarrhea and need for total parenteral nutrition (TPN) from 1977 to 1993. Children with anatomic abnormalities and/or primary immunodeficiency were excluded. There was an inverse relationship between the number of patients and the age of diarrheal onset (mean age, 2.9 ± 3.5 months). Etiology of SPD was an enteric infection in 18 cases (eightSalmonella,threeStaphylococcus,five rotavirus, one adenovirus, oneCryptosporidium), multiple alimentary intolerance (eight cases), familial microvillous atrophy (two), autoimmune enteropathy (two), celiac disease, lymphangectasia, eosinophilic enteropathy, intestinal pseudoobstruction, and intestinal neurodysplasia (1 case each). Etiology was not detected in three cases. Overall, 12 children died, five are presently being treated, and 21 had full remission. Comparative evaluation of risk factors between children with SPD and a control population of children with diarrhea but without the need for TPN showed that low birth weight, no breast feeding, history of fatal diarrhea in a relative, and early onset of diarrhea had a significantly higher incidence in the former. Social background was similar in the two populations. We conclude that a specific etiology can be identified in the majority of cases of SPD. The etiologic spectrum of SPD is broad, but an enteric infection is the most common cause of SPD. The severity of this condition is related, at least in part, to established risk factors.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Fecal excretion of leukotriene C4was determined in 26 individuals with dysentery and in 19 healthy controls. Of the patients, five were infected withShigella dysenteriaetype 1, 15 were infected withShigella flexneri,two were infected withShigella boydii,and four were infected withShigella sonnei.Three of the healthy controls were infected with non-dysenteriae Shigellae.All isolates ofShigella dysenteriaetype 1 produced Shiga toxin; the other strains were not toxigenic. Patients with dysentery due toShigella dysenteriaetype 1 excreted higher concentrations of leukotriene C4(median, 3,234 pg/0.05 g of feces) than either ill individuals infected with non-dysenteriae Shigellae(median, 202 pg/0.05 g) or healthy carriers (median, 145 pg/0.05 g) and uninfected controls (median, 129 pg/0.05 g). We propose that Shiga toxin stimulates intestinal mast cells, which release leukotriene C4, contributing to the inflammatory response inShigella dysenteriaetype 1-associated dysentery.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Differential sugar-absorption tests for measuring intestinal permeability for sugars have been studied in a variety of gastrointestinal diseases. Their use in general practice has been hampered by a lack of data on reference values and repeatability of the test and the laboratory assay. In this study, we determined the reference values of the sugar-absorption test, using lactulose and mannitol as probe molecules, for children and adults. The repeatability of the test is good; linear relationship: slope, 0.825 [95% confidence interval (CI), 0.571, 1.152); intercept, 0.005 (95% CI, −0.004, 0.010). The repeatability of the laboratory assay for the sugar-absorption test is excellent; linear relationship: slope, 1.014 (95% CI, 0.870, 1.094); intercept, 0.002 (95% CI, −0.005,0.010). The validation of the sugar-absorption test makes the test useful as a simple, noninvasive, reliable intestinal permeability test for sugars, which can be of use for clinical practice. Taking possible interfering factors into account, the sugar-absorption test can be used as a diagnostic test for enteropathy of different etiologies and evaluation of therapeutic interventions in both children and adults. Studies with the sugar-absorption test may clarify the role of intestinal permeability in the pathophysiology of a variety of gastrointestinal diseases.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Chemotherapy is a recognized cause of morphological alterations to the proximal intestine. Lactose malabsorption, the functional consequence of a small intestinal enzymatic derangement, has been shown to play an important role in causing gastrointestinal symptoms in subjects receiving chemotherapy. To establish a rational basis for the exclusion of lactose from the diet and to reduce the risk of developing gastrointestinal symptoms, we conducted a study of lactose absorption in 20 children during cancer chemotherapy. Because lactose is an important nutritional sugar, the tolerance of lactose provided by yogurt was examined. Lactose absorption was investigated by a hydrogen breath test (BT) after oral ingestion of milk (250 ml) containing physiological doses of lactose (12 g). The effect of yogurt supplementation was also tested by BT after meals of yogurt (450 g) also containing physiological doses of lactose (12.1 g). In 11 children, lactose malabsorption was detected by BT during the study before any gastrointestinal symptom revealed this status. Of these 11 children, no gastrointestinal discomfort developed in five receiving a lactose-excluded diet. In contrast, in the six children not restricted in lactose intake, gastrointestinal symptoms were observed 4 to 13 weeks after lactose malabsorption was detected by BT. The findings of our study suggested the usefulness of dietary supplementation with yogurt, a lactose-containing food, in children who developed lactose malabsorption. In fact, all lactose-malabsorbent children showed good lactose absorption and tolerance when tested by yogurt BT. Furthermore, a yogurt-supplemented diet was also successful in three subjects initially recognized as lactose intolerant. In conclusion, the data presented have important implications in reducing the risk of developing gastrointestinal symptoms in children receiving cancer chemotherapy.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

To evaluate its clinical value, the half-life of caffeine (1,3,7-trimethylxanthine) in saliva (SCT) after 3 mg/kg-1oral caffeine was measured in 53 children with chronic liver disease (mean age, 4.41 years) and 48 control children (mean age, 6.26 years) in five samples over 24 h and compared with parameters of liver function and outcome. Sensitivity was 60.3% and specificity 97% of SCT for diagnosis of chronic liver disease. The correlation of SCT with serum albumin (ALB) was −0.52 (p< 0.001), total bilirubin (SBR) was 0.585 (p< 0.001), prolonged prothrombin time (PT) was 0.387 (p= 0.004), and aspartate aminotransferase (AST) was 0.538 (p= 0.001). The correlation of SCT with a clinical score of liver dysfunction calculated from the presence of features of hepatic decompensation was 0.627 (p< 0.001) and with Malatack's paediatric prognostic score was 0.505 (p< 0.001). Serial SCT and liver function tests were performed on 53 patients on 127 occasions during a mean follow-up of 361 days (range, 4–709). Of this group, 18 were listed for liver transplantation. Predictive values of outcome by analysis of variance expressed as ratio of mean squares were SBR, 34.1 (p< 0.001); log10SCT, 20.6 (p< 0.001); ALB, 5.2 (p< 0.05); PT, 1.2 (NS). SCT correlated with clinical and biochemical parameters of severity of liver disease, but SBR was a better predictor of listing for liver transplantation in this group of paediatric patients.

ISSN:0277-2116    

出版商:OVID    

年代:1995

数据来源: OVID