ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundPoor linear growth frequently complicates chronic inflammatory bowel disease in children. Circulating inflammatory mediators may play a role in this growth delay. We evaluated the effect of experimental colitis on bone growth in a nutritionally controlled rat model.MethodsExperimental colitis was induced in male Sprague-Dawley rats (125-150 g) by enema with trinitrobenzene sulfonic acid in 50% ethanol on day 1 and 11 of a 14-day protocol. Control animals were pair-fed and all animals received a liquid rat diet (1 kcal/ml). Twenty-four-hour urine, collected on days 2 and 12 and serum samples, collected at death, were analyzed for calcium, zinc, and magnesium. Serum samples from a separate set of animals were studied for serial interleukin-6 levels. Right proximal tibias were processed for growth-plate histo-morphometry, in which linear growth is proportional to the heights of the proliferative zone, and terminal hypertrophic chondrocyte, but inversely proportional to the height of the resting zone.ResultsHistology confirmed active inflammation in the animals given trinitrobenzene sulfonic acid. Weight gain and both urinary excretion and serum levels of zinc, calcium, and magnesium did not differ between treatment and nontreatment groups. Histologically, there was impaired linear bone growth. The resting zone was greater in the colitis group (94.5 ± 32.6 μm versus 3.9 ± 5.4 μm;p< 0.05); the proliferative zone was smaller in the colitis group (123.7 ± 18.2 μm versus 78.9 ± 11.2;p< 0.05 μm); the terminal hypertrophic chondrocyte was reduced in the colitis group (19.5 ± 1.4 μm versus 28.8 ± 3.6 μm;p< 0.05). At 6 and 24 hours after induction, the level of interleukin-6 was elevated in the colitis group.ConclusionsExperimental colitis results in a decreased linear bone growth, independent of nutritional intake. Circulating cytokines derived from intestinal inflammation may contribute to the suppression of bone growth.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundAntineutrophil cytoplasmic antibodies (ANCA), particularly perinuclear ANCA (p-ANCA), have been found more frequently in sera from patients with ulcerative colitis (UC) than in sera from Crohn's disease (CD) or unclassified enterocolitis (UE) patients. This 2-center study examined sera from 102 pediatric patients with inflammatory bowel disease (IBD) to evaluate their diagnostic value and assess their relationship with disease features, distribution, activity and treatment.MethodsThe serum ANCA of 102 children with IBD were measured: 33 UC, 64 CD and 5 UE with various disease locations and degrees of activity. The mean age at the onset of symptoms was 10.7 years (1 to 16.3 years). Sera from 26 unaffected first degree relatives and 20 children without IBD were also investigated. ANCA were detected using indirect immunofluorescence of ethanol-fixed granulocytes.ResultsThere were ANCA in the sera of 24/33 children with UC (73%), 9/64 with CD (14%) and 4/5 with UE (80%). p-ANCA were more frequent than cytoplasmic-ANCA in positive sera: UC = 67%, CD = 57% and UE = 75%. The presence of ANCA was 73% sensitive and 81% specific for a diagnosis of UC, compared to other IBD (p < 0.001). Three children with proved sclerosing cholangitis associated with UC were all positive. There was no link between ANCA-positive sera and disease activity, or other endoscopic or clinical criteria. ANCA were detected in 4/26 first degree relatives (15%) and in 1/20 control subjects (5%).ConclusionsBecause of their sensitivity and specificity, ANCA may be helpful in the clinical assessment of patients with IBD, and especially those with UC. However, there is no link between the pressure of p-ANCA and the site of UC or its activity, so that it cannot be used to monitor medical treatment or surgical indications.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundAlthough the course of ulcerative proctitis in adults has been well described, little data are available concerning its clinical behavior in children and adolescents. This study sought to characterize the presentation, response to therapy, and long-term course of ulcerative proctitis in the pediatric population.MethodsA retrospective chart review was conducted at five pediatric gastroenterology centers.ResultsA total of 38 subjects (mean age 11.6 years) were identified with ulcerative proctitis (mean follow-up 4.3 years). Symptoms were mild at diagnosis in 74% and moderate or severe in 26%. Thirty-two percent had a complaint of constipation at presentation. Cessation of symptoms was noted in 68% within 3 months of therapy, an additional 24% within 6 months, and 8% were still symptomatic despite 6 months of therapy. During any subsequent yearly follow-up interval, ≈55% of patients were asymptomatic, 40% had a chronic intermittent course, and <5% were continuously symptomatic despite therapy. Eight subjects were treated with oral corticosteroids, one with 6-mercaptopurine, and one with cyclosporine. Extension of inflammation proximal to the rectosigmoid occurred in 11 of 38 subjects (29%), 0.5-11.3 years postdiagnosis. Seven of the 13 subjects (54%) followed for ≥5 years had proximal extension of disease, and two had undergone colectomy.ConclusionsDespite a mild presentation in most subjects, ulcerative proctitis seems to have a high risk of proximal extension of disease. The overall response to therapy seems to be similar to that reported for ulcerative colitis in children. Follow-up endoscopic evaluation of patients with ulcerative proctitis seems warranted, especially in the setting of recurrent or recalcitrant symptoms.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundWe evaluated the clinical utility of the13C-xylose breath test for the diagnosis of small bowel bacterial overgrowth in children.MethodsTo determine the optimal dose of13C-xylose, 29 healthy children, 3 to 12 years old, were randomly assigned to receive one of three doses of13C-xylose (10, 25, or 50 mg). After an overnight fast, the oral dose of13C-xylose was administered, and breath samples were collected every 30 minutes for 4 hours. Samples were analyzed for13CO2by gas chromatography with mass spectrometry. Using the 50 mg dose, we then performed nine breath tests with concurrent duodenal bacterial cultures in 6 children, 3 to 12 years old, with short-bowel syndrome (n = 2), immunodeficiency states (n = 1), and motility disorders (n = 3).ResultsExcretion of13CO2in breath peaked at 2.5 hours in all three control groups. The 50-mg dose produced the highest median peak and the smallest range of13CO2excretion in breath within each time period. The time of peak13CO2excretion in breath varied among the diseased children; however, the six patients with small-bowel bacterial overgrowth (2 × 105- 3.5 × 108gram negative rods) all had peak13CO2that exceeded the maximum breath13CO2level in breath of the control subjects at the corresponding time period (100% sensitivity). Of the three patients with negative cultures, two had negative breath test results and one had positive results (67% specificity). One subject had normalization of both duodenal culture and breath test results after antibiotic treatment of small-bowel bacterial overgrowth.ConclusionsOur preliminary results suggest that with a dose of 50 mg13C-xylose, breath test results reliably predict small-bowel bacterial overgrowth in susceptible children.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundPlasmin is the major endogenous protease present in milk. The level of plasmin activity is controlled by the availability of the precursor plasminogen and by the levels of plasminogen activators and inhibitors. Recently, a differential distribution of tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) has been demonstrated in bovine milk. To assess whether this distribution pattern is a general feature, the occurrence of components of the plasminogen activation system in different fractions of human milk was investigated.MethodsMilk samples were separated into the following fractions; milk fat, skim milk, and milk cells by centrifugation. The different fractions were detected for the presence of plasminogen and plasminogen activators by immunoblotting and zymography. The distribution of t-PA and u-PA was investigated by ligand binding analysis. t-PA-catalyzed plasminogen activation was examined by a coupled chromogenic assay.ResultsA differential distribution of plasminogen, t-PA, and u-PA was found. Casein micelles were found to exhibit t-PA and plasminogen binding activity, whereas the u-PA receptor was identified as the u-PA binding component in the cell fraction. Furthermore, human casein enhanced t-PA-catalyzed plasminogen activation, comparable to the enhancing effect obtained with fibrinogen fragments.ConclusionThe finding of a differential distribution of u-PA and t-PA in milk suggests that the two activators may have different physiological functions, which involve protection against invading microorganisms and maintenance of patency and fluidity in the ducts of mammary gland, respectively.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundHuman milk contains palmitic acid predominantly in the triglyceride sn-2 position, and differs from the palmitic acid positional distribution found in most infant formulas (predominantly positions sn-1 and sn-3). Following lipolysis by pancreatic lipase, 2-monoglycerides and free fatty acids are produced. All 2-monoglycerides are well absorbed, including 2-monopalmitin, thus providing one reason for the efficient absorption of palmitic acid in breast-fed infants. If infants are fed fat blends with palmitic acid located in the sn-1 and sn-3 positions, the resulting free fatty acids may form poorly absorbed calcium soaps. Therefore, many infant formulas contain only modest levels of palmitic acid.MethodsFat absorption studies were conducted in rats with preparations containing various amounts of palmitic acid in the triglyceride sn-2 position. Determining total fat absorption, specific fatty acid absorption, and the presence of calcium-fatty acid soaps.ResultsBetapol, a new triacylglycerol, similar to human milk in its palmitic acid content and positional distribution, demonstrated excellent absorption characteristics compared to fat blends derived from either palm olein or oleo (similar in fatty acid profile to Betapol, but with most palmitic acid in the sn-1 and sn-3 positions). A five-point dose response was used to further evaluate the relationship of positional distribution and fat loss. Palmitic acid excretion and fecal fatty acid soaps were negatively correlated to the presence of palmitic acid in the sn-2 position.ConclusionThese studies provide evidence that palmitic acid can be efficiently absorbed, avoiding fatty soap formation of it is present in the sn-2 position.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundReference values for the main indices of body fat distribution in children are not available.MethodsThe study population comprised 1638 Caucasian children and adolescents: 848 boys and 790 girls, with ages ranging from 4.0 to 14.9 years, and living in the central part of Spain (Provincia de Zaragoza). The waist-to-hip circumference ratio and the triceps-to-subscapular skinfold thickness ratio were measured.ResultsIn boys, mean waist-to-hip circumference ratio ranges from 0.834, at 13.5 years, to 0.896 at 4.5 years. In girls, waist-to-hip circumference ratio ranges from 0.756, at 14.5 years, to 0.877, at 4.5 years. We observed a decrease of waist-to-hip circumference ratio with age, especially in girls. In boys, triceps-to-subscapular skinfold thickness ratio ranges from 1.360, at age 14.5, to 1.704, at age 5.5. In girls, triceps-to-subscapular skinfold thickness ratio ranges from 1.468, at age 13.5, to 1.727, at age 9.5. We observed a decrease with age only in boys.ConclusionsWe present reference values for the main indices of body fat distribution, which could be useful in clinical practice. However, research is needed that will compare these indices with data on body fat distribution obtained by a gold standard method, such as computed tomography or magnetic resonance imaging.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundEnteric cryptosporidiosis is a frequent problem in adults with human immunodeficiency virus (HIV) infection, but little is known of its features in children. The aim of this study was to investigate the incidence and the clinical features of cryptosporidiosis in HIV-infected children.MethodsThirty-five children with symptomatic HIV infection were screened every 2 months, and in case of diarrhea, for the presence ofCryptosporidium. Intestinal function tests were performed, and the fecal osmotic gap was measured in children with cryptosporidiosis.ResultsSeventy episodes of diarrhea occurred in 16 children in a median period of 17 months.Cryptosporidiumwas detected in five cases, all with full-blown acquired immunodeficiency syndrome. Cryptosporidiosis was significantly more protracted than any other form of diarrhea and was associated with dehydration and severe weight loss. Intestinal function was not modified during cryptosporidiosis. Osmotic gap values were consistent with secretory rather than osmotic diarrhea. In four cases, recovery was observed without specific treatment.ConclusionsEnteric cryptosporidiosis is a severe problem in advanced stages of HIV infection. It does not induce intestinal malabsorption. It induces diarrhea of secretory type. Recovery may be observed independently of therapy.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

BackgroundImpaired glucose tolerance and secondary diabetes are frequent in older patients with cystic fibrosis (CF), associated with increased frequency of infections and reduced life expectancy. Studies on the pathophysiology of islet cell secretion in CF are a prerequisite for a scientifically based therapeutic approach.MethodsOral glucose tolerance tests were performed in 71 patients (14.2 ± 0.5 years; mean ± SE) and 56 control subjects (16.5 ± 0.9 years). Glucose, insulin, C-peptide, and proinsulin were measured every 30 min.ResultsGlucose tolerance in CF patients was classified as normal (NGT, n = 48), impaired (IGT, n = 14), or diabetic (DM, n = 9). Even in CF patients with NGT, blood glucose was significantly elevated at 30, 60, and 90 min of the test. Surprisingly, the secretory responses of insulin and C-peptide were not reduced in CF patients with IGT or DM compared with both healthy controls or CF patients with normal glucose tolerance. However, peak insulin concentration was reached at 90 min in CF-IGT or CF-DM patients compared with 30 min in controls. The ratio of glucose to insulin, an indicator of insulin resistance, increased in CF patients with progression of carbohydrate intolerance. Proinsulin was significantly reduced in all CF patients compared with controls (p < 0.001; Wilcoxon's rank sum test).ConclusionsIn CF patients with impaired glucose tolerance or diabetes, integrated insulin release is not diminished, indicating that insulin resistance is likely to contribute to hyperglycemia in CF patients with IGT or DM. Reduced proinsulin levels in CF patients are compatible either with enhanced conversion of proinsulin to insulin in compensation for reduced β-cell mass, or enhanced clearance of proinsulin.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID