A Kluyveromyces marxianus 2-deoxyglucoseresistant mutant with enhanced activity of xylose utilization

Thermotolerant ethanologenic yeast Kluyveromyces marxianus is capable of fermenting various sugars including xylose but glucose represses to hamper the utilization of other sugars. To acquire glucose repression-defective strains, 33 isolates as 2-deoxyglucose (2-DOG)-resistant mutants were acquired from about 100 colonies grown on plates containing 2-DOG, which were derived from an efficient strain DMKU 3-1042. According to the characteristics of sugar consumption abilities and cell growth and ethanol accumulation along with cultivation time, they were classified into three groups. The first group (3 isolates) utilized glucose and xylose in similar patterns along with cultivation to those of the parental strain, presumably due to reduction of the uptake of 2-DOG or enhancement of its export. The second group (29 isolates) showed greatly delayed utilization of glucose, presumably by reduction of the uptake or initial catabolism of glucose. The last group, only one isolate, showed enhanced utilization ability of xylose in the presence of glucose. Further analysis revealed that the isolate had a single nucleotide mutation to cause amino acid substitution (G270S) in RAG5 encoding hexokinase and exhibited very low activity of the enzyme. The possible mechanism of defectiveness of glucose repression in the mutant is discussed in this paper (AU)

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Morphological and functional alterations of small intestine in chronic pancreatitis.

CONTEXT: The small intestine in chronic pancreatitis has not been investigated yet thoroughly. It would be important to understand fat metabolism in the course of this disease and could be explained if the small intestine has some pathological conditions and, due to this reason, pancreatic enzyme substitution does not work in all patients. OBJECTIVE: To investigate the pathophysiology of small intestine in chronic pancreatitis and to show the reason why in some cases pancreatic enzyme substitution does not work properly. PATIENTS: In the process of the study 33 chronic pancreatitis patients have been examined. CONTROLS: The control group includes 30 subjects without chronic pancreatitis similar for age, sex and alcohol consumption to the patients with chronic pancreatitis patients. INVESTIGATIONS: Aspiration biopsy of jejunum mucosa followed by histological examination and investigation of intestinal enzymes by aspiration has been performed. MAIN OUTCOME MEASURES: Metabolism at membranic level has been studied by enzymatic activity of amylase and lipase in the small intestine. Production of enzymes (monoglyceride lipase, lactase, saccharase, maltase, glycyl-l-leucine dipeptidase) promoting metabolism in enterocytes has been estimated as to their activity in homogenates of jejunum mucosa samples. Participation of mucosa in intestinal digestion has been assessed by alkaline phosphatase activity in a secretory chyme from proximal portion of jejunum. Absorptive capacity of jejunum was evaluated by D-xylose test results. DNA, lysozyme, immunoglobulin contents of chyme have also been calculated and bacteriological study of chyme has been also performed. RESULTS: Secondary enteritis, accompanied by moderate dystrophic changes of mucous membrane, thinning of limbus, and decrease of Paneth cell mitotic index, was found to occur in chronic pancreatitis patients. Enteritis is followed by changes in enzymatic processes in the sphere of membrane and intestinal digestion, decrease of absorption, accelerated desquamation of epithelium, fall in local immunity and development of bacterial overgrowth syndrome. CONCLUSIONS: Existence of secondary enteritis and bacterial overgrowth syndrome validates lack of enzyme replacement therapy efficacy in some chronic pancreatitis patients with pancreatic insufficiency. To optimize treatment in such cases it is important to perform small intestine decontamination and escalate enzyme preparation dosage.

[A method for simultaneous assay of propulsion and absorption in small intestine].

OBJECTIVE: To develop a method for simultaneous assay of propulsion and absorption in small intestine. METHODS: The mice were administrated through gastric tube with mixed reagents containing 0.12% phenol red, D-xylose (1.25%, 2.5% and 5%) and 15% gelatin. The influence of phenol red on D-xylose absorption and the influence of D-xylose on small intestine propulsion rate were investigated by measuring serum concentration of D-xylose with phloroglucinol method. RESULTS: At 10 min, no significant difference was found between 5% D-xylose mixed reagent group and 5% D-xylose control. At 15 min, small intestine propulsion rate in 5% D-xylose mixed reagent group, but not in 2.5% and 1.25% D-xylose mixed reagent groups, was significantly higher than in phenol red control (P<0.05). CONCLUSION: Gastric administration of mixed reagent containing 0.12% phenol red, 5% D-xylose and 15% gelatin can simultaneously assay propulsion and absorption of small intestine in mice.

The effect of tannic acid and polyethylene glycol on the absorption capacity of chicken intestine for d-xylose and ß-carotene.

In an experiment, the possible influence of tannic acid (TA) and polyethylene glycol (PEG) on the absorption capacity of intestine for d-xylose and ß-carotene in broiler chicken was investigated. Four groups of nine 28-day-old broiler cockerels received d-xylose (500 mg) and ß-carotene (52 µg) solutions (Group 1 to 4) with TA (1 g, Group 2 to 4) and PEG (500 mg Group 3 and 1 g Group 4), orally. One blood sample prior to, and four others after the administration of test materials, were collected from wing vein on 40 min basis, for 160 min and the concentration of plasma d-xylose was determined. The concentration of ß-carotene was also measured in plasma of blood samples taken prior to and 160 min post-administration of the test materials. Plasma d-xylose concentration of all groups showed quadratic correlations with time (p < 0.001, r(2) = 0.84, 0.60, 0.70 and 0.74 for Group 1 to 4, respectively). Administration of TA reduced the plasma concentration of d-xylose in Group 2. However, feeding PEG after TA raised the concentration of d-xylose in Group 4 to the level that there was no difference in that variable between this group and Group 1. Although the plasma concentration of ß-carotene was increased in 160 min post-ingestion of the test material, no difference was found in that variable among the experimental groups. In conclusion, TA and its interaction with PEG have impacts on the absorption capacity of intestine for d-xylose and highly likely other simple sugars, but TA or PEG have no influence on the absorption of ß-carotene and most probably other fat soluble vitamins.

The effect of sedation on D(+)-xylose absorption tests in 6 normal horses.

REASONS FOR PERFORMING STUDY: D(+)-xylose absorption tests are commonly performed when investigating suspected small intestinal malabsorption in the horse. The test involves the administration of a D(+)-xylose solution via a nasogastric tube followed by serial blood sampling to determine its rate of absorption. In some horses, nasogastric intubation cannot be safely performed without prior administration of a sedative. Due to its short duration of action, the α(2) agonist xylazine is commonly used for this purpose. However, α(2) agonists have also been reported to influence the rate of gastric emptying as well as small intestinal motility patterns. OBJECTIVE: To evaluate if prior sedation with xylazine would influence the rate of absorption of D(+)-xylose in 6 normal Standardbred horses in a randomised cross-over study. METHODS: D(+)-xylose was administered by nasogastric intubation at a dose rate of 0.5 g/kg bwt given as a 10% solution with water while xylazine was administered iv at a dose rate of 0.5 mg/kg bwt. A heparinised blood sample was collected prior to administration of D(+)-xylose (and xylazine when used) and then at 30, 45, 60, 75, 90, 120, 150, 180 and 240 min following administration. Samples were immediately analysed using a modified colorimetric micro method. The cumulative amount of D(+)-xylose absorbed at each time point with and without prior sedation were. The significance rate was set at P<0.05. RESULTS: The study failed to demonstrate a statistically significant difference in the amount of D(+)-xylose absorbed between sedated and unsedated animals, although there was a tendency for a less rapid initial uptake with prior sedation. CONCLUSION: This study suggests that prior sedation with xylazine will not significantly affect the result of a D(+)-xylose absorption test in the normal horse.

Reduced ¹³C-D-xylose absorption in alcoholics is more likely caused by alterations in small intestinal mucosa than delayed gastric emptying.

OBJECTIVE: Alterations of the small intestinal absorptive surface are a probable cause of D-xylose malabsorption in chronic alcoholism. Delayed gastric emptying, however, may influence the (13)C-D-xylose breath test, which is used to study intestinal function in alcoholics. The aim of this study was to measure gastric emptying in alcoholics to elucidate whether retention of the test meal could explain the malabsorptive pattern of the (13)C-D-xylose breath test observed in alcoholics. MATERIAL AND METHODS: Fifteen alcoholics performed the (13)C-octanoic acid and the (13)C-D-xylose breath tests on consecutive days in a random order. The (13)CO(2) expired was measured every 30 or 15 min for 4 h in the (13)C-D-xylose and the (13)C-octanoic acid breath tests, respectively, using a mass spectrometer equipped with a gas chromatograph. Test meals consisted of 100 mg of (13)C-D-xylose and 5 g of unmarked D-xylose dissolved in 250 ml water and 91 mg (13)C-octanoic acid embedded in a one-egg omelette served with white bread with margarine, respectively. RESULTS: The alcoholic patients had a lower (13)C-D-xylose breath index compared with healthy controls (p < 0.0001). None of the (13)C-octanoic acid breath test variables, T(50%), T(max), T(lag), or GEC revealed any significant differences between the groups. CONCLUSION: The pathological (13)C-D-xylose breath test in this group of alcoholics is unlikely to be caused by delayed gastric emptying. Malabsorption is the probable cause of the pathological (13)C-D-xylose breath test results in alcoholics.

Discovery of novel N-ß-D-xylosylindole derivatives as sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors for the management of hyperglycemia in diabetes.

A novel series of N-linked ß-D-xylosides were synthesized and evaluated for inhibitory activity against sodium-dependent glucose cotransporter 2 (SGLT2) in a cell-based assay. Of these, the 4-chloro-3-(4-cyclopropylbenzyl)-1-(ß-D-xylopyranosyl)-1H-indole 19m was found to be the most potent inhibitor, with an EC(50) value similar to that of the natural SGLT2 inhibitor phlorizin. Further studies in Sprague-Dawley (SD) rats indicated that 19m significantly increased urine glucose excretion in a dose-dependent manner with oral administration. The antihyperglycemic effect of 19m was also observed in streptozotocin (STZ) induced diabetic SD rats. These results described here are a good starting point for further investigations into N-glycoside SGLT2 inhibitors.

[Effects of Sijunzi Decoction on urine's xylose excretion rate and ATP in mucosa of spleen deficiency rats].

OBJECTIVE: To observe the effects of Sijunzi Decoction on D-xylose excretion rate and ATP content in the mucosa membranes of small intestines of rats with spleen deficiency. METHODS: Spleen deficiency model rats were made by reserpine injection. D-xylose excretion rate was measured with p-bromoaniline method, and the ATP content of small intestines mucosa was detected with bioluminescence method. The correlation between D-xylose excretion rate and ATP content of mucosa was also analyzed. RESULTS: Rats' body weight and D-xylose excretion rate decreased after reserpine injection (P < 0.01, vs control group), but increased after treated with Sijunzi Decoction (P < 0.05, vs model group). The ATP content of mucosa showed no significant difference between model group and control group. There was obviously positive correlation between the change of urine's D-xylose excretion rate and mucosa ATP content. CONCLUSION: Sijunzi Decoction has the activity of improving xylose absorption in spleen deficiency rats, but no obvious effect on their mucosa ATP content. The reducing of urine's D-xylose excretion rate in spleen deficiency rats is accompanied with the decrease of mucosa ATP content.

Effects of nucleotide supplementation in milk replacer on small intestinal absorptive capacity in dairy calves.

Milk replacer was supplemented with nucleotides and fed to dairy calves from birth through weaning to examine the potential for enhancing recovery of small intestinal function after enteric infection. Three treatments of 23 calves each were fed milk replacer (10% body weight/d) supplemented with no nucleotides (C), purified nucleotides (N), or nucleotides from an extract of Saccharomyces cerevisiae (S). Average daily gain, health scores, fecal dry matter, and fecal bacteria were monitored, and blood was analyzed for packed cell volume, glucose, blood urea nitrogen (BUN), and creatinine. Calves were monitored twice daily for fecal score, and 48 h after increased fecal fluidity was recorded, intestinal function was evaluated by measuring absorption of orally administered xylose (0.5 g/kg of body weight). Packed cell volume of blood was greater for treatment N for wk 2 and 5 compared with other treatment groups. Four calves per treatment were killed, and intestinal tissue was evaluated for morphology, enzyme activities, and nucleoside transporter mRNA expression. Treatment S calves had increased abundance of nucleoside transporter mRNA, numerically longer villi, and lower alkaline phosphatase than other groups. Growth measurements and plasma concentrations of glucose, BUN, creatinine, and IgG were not different between treatments; however, BUN-to-creatinine ratio was higher for treatment N, possibly indicating decreased kidney function. There were also no treatment effects on fecal dry matter and fecal bacteria population. However, N-treated calves had the highest detrimental and lowest beneficial bacteria overall, indicating an unfavorable intestinal environment. Supplementation of purified nucleotides did not improve intestinal morphology or function and resulted in higher fecal water loss and calf dehydration. Supplementation of nucleotides derived from yeast tended to increase calf intestinal function, provide a more beneficial intestinal environment, and improve intestinal morphology.

Effect of Cryptosporidium parvum infection on the absorptive capacity and paracellular permeability of the small intestine in neonatal calves.

Cryptosporidium parvum is recognized as one of the most important pathogens causing enteritis and severe diarrhoea in calves up to 1 month of age. Although the infection may be responsible for some mortality, its impact is mainly associated with the impairment of intestinal functions and lower performance of animals. The aim of this study was to determine the effect of cryptosporidiosis on the intestinal functions in neonatal experimentally infected Holstein calves. Absorption tests with d-xylose and retinyl-palmitate, and the lactulose/mannitol test of intestinal permeability were simultaneously performed in 1-week intervals from challenge to full recovery. In infected animals, reduced intestinal absorptive capacity for both D-xylose and retinyl-palmitate was observed on day 7 post-infection (p.i.). At the same time, a more than 100% elevation of intestinal permeability was observed in the infected calves. All intestinal functions, except absorption of retinyl-palmitate, were significantly affected and changes were detected up to day 14 p.i. In contrast, results of all tests obtained on day 21 p.i. suggest full recovery of the infected intestine. Significantly, growth of the calves which had recovered from cryptosporidiosis was still affected between days 14 and 21 p.i.

Effect of preoperative administration of erythromycin or flunixin meglumine on postoperative abomasal emptying rate in dairy cows undergoing surgical correction of left displacement of the abomasum.

OBJECTIVE: To determine whether preoperative administration of erythromycin or flunixin meglumine altered postoperative abomasal emptying rate, rumen contraction rate, or milk production in dairy cattle undergoing surgical correction of left displacement of the abomasum (LDA). DESIGN: Nonrandomized, controlled clinical trial. ANIMALS: 45 lactating Holstein-Friesian cows with LDA. PROCEDURES: Cows were alternately assigned to an erythromycin (10 mg/kg [4.5 mg/lb], IM), flunixin (2.2 mg/kg [1.0 mg/lb], IV), or control group (n = 15/group). Treatments were administered once 1 hour before surgical correction of LDA. D-Xylose solution (50%; 0.5 g/kg [0.23 g/lb]) was injected into the abomasal lumen during surgery, and venous blood samples were periodically obtained to determine time to maximum serum D-xylose concentration. RESULTS: Abomasal emptying rate was significantly faster in cows treated with erythromycin (mean +/- SD time to maximum serum D-xylose concentration, 149 +/- 48 minutes) than in control cows (277 +/- 95 minutes) but was not significantly different between cows treated with flunixin (230 +/- 49 minutes) and control cows. Cows treated with erythromycin had significantly greater milk production, relative to production before surgery, on postoperative days 1 and 2 than did control cows. Cows in the erythromycin and flunixin groups had a significantly higher rumen contraction rate on the first postoperative day than did control cows. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that preoperative administration of a single dose of erythromycin increased abomasal emptying rate, rumen contraction rate, and milk production in the immediate postoperative period in cows undergoing surgical correction of LDA.

13C-xylose and 14C-xylose breath tests for the diagnosis of coeliac disease.

OBJECTIVES: Xylose absorption testing has traditionally involved measurement of serum xylose and/or measurement of excreted xylose in urine. However, by enriching xylose with a 13C- or 14C-isotope, absorption of an oral xylose load will be reflected in the time-dependent pattern of 13CO2 or 14CO2 exhaled in breath. Our objectives were to evaluate the diagnostic properties of 13C-xylose and 14C-xylose breath tests in coeliac disease, and to develop a diagnostic breath test index. MATERIAL AND METHODS: We reviewed data from 41 coeliac patients who underwent the 14C-xylose breath test before and after commencement of a gluten-free diet, and 60 coeliac patients who underwent the 13C-xylose breath test, 37 of whom repeated the test after starting a gluten-free diet. Coeliac patients were compared with healthy control subjects. RESULTS: Coeliac patients exhaled significantly less 13CO2 or 14CO2 than healthy controls during the first hour of the test and more isotope-labelled CO2 than control subjects after 3 h. Diagnostic accuracy was optimal with test duration of 210 min combining gas measurements at 30 min and 210 min in a simple fraction. This gas fraction index (30 min/210 min) distinguished between coeliac patients and healthy control subjects with 84-95% sensitivity and 87-94% specificity. After commencement of a gluten-free diet, the gas fraction index increased in most coeliac patients, but remained lower than that in healthy control subjects. CONCLUSIONS: 13C-xylose- and 14C-xylose breath tests discriminate between coeliac patients and healthy control subjects with high sensitivity and specificity. The stable isotope 13C-xylose breath test has comparable diagnostic accuracy to the radioactive isotope 14C-xylose breath test and should be the preferred alternative to traditional xylose absorption tests.

Long-term biokinetics and radiation exposure of patients undergoing 14C-glycocholic acid and 14C-xylose breath tests.

The (14)C-glycocholic acid and (14)C-xylose breath tests are clinically used for the diagnosis of intestinal diseases, such as bacterial overgrowth in the small intestine. The two tests have in earlier studies been thoroughly evaluated regarding their clinical value, but due to the long physical half-life of (14)C and the limited biokinetic and dosimetric data, which are available for humans, several hospitals have been restrictive in their use. The aim of this study was to investigate the long-term biokinetics and dosimetry of the two (14)C compounds in patients and volunteers, using the highly sensitive accelerator mass spectrometry (AMS) technique. Eighteen (18) subjects were included, 9 for each compound. The (14)C content in samples from exhaled air, urine, and, for some subjects, also feces were analyzed with both liquid scintillation counting (LSC) and AMS. The results from the glycocholic acid study showed that, up to 1 year after the administration, 67%+/-6% (mean+/-standard deviation) of the administered activity was recovered in exhaled air, 2.4%+/-0.4% was found in urine, and 7.6% (1 subject) in feces. In the xylose study, the major part was found in the urine (66%+/-2%). A significant part was exhaled (28%+/-5%), and the result from an initial 72-hour stool collection from 2 of the subjects showed that the excretion by feces was insignificant. The absorbed dose to various organs and tissues and the effective dose were calculated by using biokinetic models, based on a combination of experimental data from the present study and from earlier reports. In the glycocholic acid study, the highest absorbed dose was received by the colon (1.2 mGy/MBq). In the xylose study, the adipose tissue received 0.8 mGy/MBq. The effective dose was estimated to 0.5 (glycocholic acid) and 0.07 mSv/MBq (xylose). Thus, from a radiation protection point of view, we see no need for restrictions in using the two (14)C-labeled radiopharmaceuticals on adults with the activities normally administered (0.07-0.4 MBq).

Altered intestinal function in patients with chronic heart failure.

OBJECTIVES: We evaluated morphology and function of the gut in patients with chronic heart failure (CHF). BACKGROUND: Intestinal translocation of bacterial endotoxin may contribute to the inflammatory state observed in patients with CHF. The morphology and function of the gut may be abnormal. METHODS: We studied 22 patients with CHF (age 67 +/- 2 years, left ventricular ejection fraction [LVEF] 31 +/- 1%, New York Heart Association functional class 2.3 +/- 0.1, peak VO2 15.0 +/- 1.0 ml/kg/min) and 22 control subjects (62 +/- 1 years, LVEF 68 +/- 2%, peak VO2 24.7 +/- 1.3 ml/kg/min). Bowel wall thickness was assessed by transcutaneous sonography, small intestinal permeability by the lactulose-mannitol test, passive carrier-mediated transport by D-xylose test, large intestinal permeability by sucralose test (5- and 26-h urine collection, high-performance liquid chromatography), and mucosal bacterial biofilm by fluorescence in situ hybridization in biopsies taken during sigmoidoscopy. RESULTS: Chronic heart failure patients, compared with control patients, showed increased bowel wall thickness in the terminal ileum (1.48 +/- 0.16 mm vs. 1.04 +/- 0.08 mm), ascending colon (2.32 +/- 0.18 mm vs. 1.31 +/- 0.14 mm), transverse colon (2.19 +/- 0.20 vs. 1.27 +/- 0.08 mm), descending colon (2.59 +/- 0.18 mm vs. 1.43 +/- 0.13 mm), and sigmoid (2.97 +/- 0.27 mm vs. 1.64 +/- 0.14 mm) (all p < 0.01). Chronic heart failure patients had a 35% increase of small intestinal permeability (lactulose/mannitol ratio: 0.023 +/- 0.001 vs. 0.017 +/- 0.001, p = 0.006), a 210% increase of large intestinal permeability (sucralose excretion: 0.62 +/- 0.17% vs. 0.20 +/- 0.06%, p = 0.03), and a 29% decrease of D-xylose absorption, indicating bowel ischemia (26.7 +/- 3.0% vs. 37.4 +/- 1.4%, p = 0.003). Higher concentrations of adherent bacteria were found within mucus of CHF patients compared with control subjects (p = 0.007). CONCLUSIONS: Chronic heart failure is a multisystem disorder in which intestinal morphology, permeability, and absorption are modified. Increased intestinal permeability and an augmented bacterial biofilm may contribute to the origin of both chronic inflammation and malnutrition.

Influence of dietary tannic acid and polyethylene glycol on growth and intestinal D-xylose absorption of broiler cockerels and activity of serum enzymes.

1. In an experiment on broiler cockerels, the influence of tannic acid (TA) and polyethylene glycol (PEG) on body weight gain (BWG), feed conversion ratio (FCR), weight of intestine and liver, the activities of serum enzymes LDH, AST, ALT and intestinal absorption function were investigated. 2. Broiler cockerels were given either a commercial diet alone (control group) or a commercial diet with TA (20 g/kg), PEG (10 g/kg) or TA plus PEG (20 + 10 g/kg), for 10 d. 3. On the last day of the experiment, all birds and remaining feed were weighed individually and a sample of blood was taken to measure the serum activities of lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The capacity of intestinal cells for the absorption of D-xylose was measured. Finally all birds were killed humanely and the intestine and liver were weighed. 4. The results showed that TA significantly reduced BWG and FCR, as well as the activity of LDH, AST and ALT. 5. TA also increased the relative weight of the intestine. Adding PEG alone had no effect on any of the measured parameters. 6. However, PEG improved significantly BWG, FCR and the activity of LDH and AST of TA-fed birds. 7. The plasma D-xylose concentration of experimental birds was similar for all dietary treatments most likely because of temporal separation between feeding the dietary TA and administering the D-xylose. 8. It was concluded that the presence of tannins in the GI lumen of the bird was necessary to affect the processes involved in the absorption of simple sugars such as D-xylose, at the level of intestinal absorptive cells.

Aspectos funcionais, microbiológicos e morfológicos intestinais em crianças infectadas pelo vírus da imunodeficiência humana / Functional, microbiological and morphological intestinal findings among human immunodeficiency virus infected children

RACIONAL: O trato gastrointestinal é freqüentemente acometido nas crianças infectadas pelo vírus da imunodeficiência humana, com importantes repercussões no seu estado nutricional e sobrevida. A maioria dos estudos relacionados a esse tema foi desenvolvida com adultos, sendo menos investigado o problema nas crianças OBJETIVOS: Estudar aspectos digestivo-absortivos, microbiológicos e morfológicos intestinais em crianças infectadas pelo vírus da imunodeficiência humana MATERIAL E MÉTODOS: Onze crianças infectadas pelo vírus da imunodeficiência humana, menores de 13 anos, pertencentes às categorias clínicas A, B ou C, divididas em dois grupos: cinco pacientes com relato atual ou recente de diarréia e seis pacientes sem diarréia nos 30 dias que antecederam à inclusão no estudo. Investigação proposta: biopsia de intestino delgado e reto para análise morfológica e microbiológica, coprocultura, protoparasitológico de fezes, pesquisa de rotavírus, micobactérias e Cryptosporidium; teste da D-xilose RESULTADOS: Todos os pacientes testados (9/11) apresentavam má absorção da D-xilose (8,4-24,4 mg/dL). Os achados histopatológicos de intestino delgado foram inespecíficos, representados em sua maioria, por enteropatia grau I a II (6/10). Em todos os casos foi constatado aumento do infiltrado celular do córion. As alterações histopatológicas do reto também foram inespecíficas, com presença de aumento do infiltrado celular do córion. A pesquisa de microorganismos enteropatogênicos só foi positiva em dois casos, sendo identificado Mycobacterium avium intracellulare e Cryptosporidium nas fezes CONCLUSÕES: Demonstrou-se alta prevalência (100 por cento) de má absorção intestinal em crianças infectadas pelo vírus da imunodeficiência humana, com ou sem diarréia. Não foi possível estabelecer correlações quanto à presença de agentes enteropatogênicos, má absorção intestinal, alterações morfológicas intestinais e ocorrência ou não de diarréia. Não houve correlação...

BACKGROUD: Gastrointestinal tract disorders are frequent among human immunodeficiency virus infected children, with important repercussions on nutrition and survival. Most studies related to this subject were restricted to adults, being less investigated the problem in the children. AIMS: To study intestinal digestion, absorption, microbiological and morphological findings among human immunodeficiency virus infected children. MATERIAL AND METHODS: Eleven human immunodeficiency virus infected children under 13 years old, belonging to clinical categories A, B or C, separated in two groups: five patients with current or recent episode of diarrhea and six patients without diarrhea in the last 30 days preceding entering in study. Investigation proposed: microbiological and morphological analysis of small intestine and rectum biopsy; stool exams for bacterium, parasite, rotavirus, Mycobacterium species and Cryptosporidium; D-xylose test RESULTS: All tested subjects (9/11) had low D-xylose absorption (8,4 _ 24,4 mg d/L). Small intestinal mucosa histology findings were nonspecific, represented, in majority, of grade I/II enteropathy (6/10). Increased cellular infiltration of the chorion was observed in all specimens. Rectum histology alterations were also nonspecific, with chorion increased cellular infiltration. Mycobacterim avium intracellulare and Cryptosporidium were the solely microorganisms founded, both in stool CONCLUSIONS: Our study demonstrated high prevalence (100 percent) of intestinal malabsorption among human immunodeficiency virus infected children, despite the occurrence or not of diarrhea. It was not possible to establish relationships between the presence of microorganisms, intestinal malabsorption, intestinal morphologic findings and the occurrence or not of diarrhea. There was no correlation between D-xylose and intensity of villous atrophy.

Early intestinal changes following abdominal radiotherapy comparison of endpoints.

PURPOSE: To compare tests for intestinal function with clinical scores after abdominal irradiation. PATIENTS AND METHODS: At the Department of Radiotherapy, Erfurt, Germany, intestinal changes were studied in 91 patients receiving abdominal radiotherapy between 1992 and 1996. Conventional fractionation (1.8-2 Gy per fraction, total doses 30.6-62.5 Gy) was applied. Before and at weekly intervals during radiotherapy, the clinical response was scored according to RTOG/EORTC for the upper and lower gastrointestinal (GI) tract. Resorption tests for vitamin B(12) and D-xylose were performed before the onset and immediately after treatment. RESULTS: The clinical response displayed a well-defined dose-effect relationship with grade 1 effects in 5% and 50% of the patients at about 10 Gy and 50 Gy, respectively. For grade 2 reactions, 5%- and 50%-effective doses were 20-30 Gy and 60-80 Gy. Effects in the upper and lower GI tract were highly correlated. Changes in body weight did not show a correlation with other clinical symptoms. Changes in resorption also displayed a significant dose effect. However, no correlation was found with the clinical symptoms in the individual patient. CONCLUSION: In the present study, the clinical manifestation of intestinal side effects according to RTOG/EORTC criteria was reflected by neither the vitamin B(12) nor by the D-xylose resorption test. Hence, these tests cannot be regarded as useful for objective quantitation of intestinal radiation injury.

[Functional, microbiological and morphological intestinal findings among human immunodeficiency virus infected children]. / Aspectos funcionais, microbiológicos e morfológicos intestinais em crianças infectadas pelo vírus da imunodeficiência humana.

BACKGROUND: [corrected] Gastrointestinal tract disorders are frequent among human immunodeficiency virus infected children, with important repercussions on nutrition and survival. Most studies related to this subject were restricted to adults, being less investigated the problem in the children. AIMS: To study intestinal digestion, absorption, microbiological and morphological findings among human immunodeficiency virus infected children. MATERIAL AND METHODS: Eleven human immunodeficiency virus infected children under 13 years old, belonging to clinical categories A, B or C, separated in two groups: five patients with current or recent episode of diarrhea and six patients without diarrhea in the last 30 days preceding entering in study. Investigation proposed: microbiological and morphological analysis of small intestine and rectum biopsy; stool exams for bacterium, parasite, rotavirus, Mycobacterium species and Cryptosporidium; D-xylose test RESULTS: All tested subjects (9/11) had low D-xylose absorption (8,4 _ 24,4 mg d/L). Small intestinal mucosa histology findings were nonspecific, represented, in majority, of grade I/II enteropathy (6/10). Increased cellular infiltration of the chorion was observed in all specimens. Rectum histology alterations were also nonspecific, with chorion increased cellular infiltration. Mycobacterim avium intracellulare and Cryptosporidium were the solely microorganisms founded, both in stool CONCLUSIONS: Our study demonstrated high prevalence (100%) of intestinal malabsorption among human immunodeficiency virus infected children, despite the occurrence or not of diarrhea. It was not possible to establish relationships between the presence of microorganisms, intestinal malabsorption, intestinal morphologic findings and the occurrence or not of diarrhea. There was no correlation between D-xylose and intensity of villous atrophy.

Use of the D-xylose absorption test to measure abomasal emptying rate in healthy lactating Holstein-Friesian cows and in cows with left displaced abomasum or abomasal volvulus.

We determined the abomasal emptying rates of Holstein-Friesian cows at different stages of lactation, with left displaced abomasum (LDA), or immediately after surgical correction of LDA or abomasal volvulus (AV). D-xylose (0.5 g/kg body weight [BW], 50% solution) was injected into the abomasum in healthy cows (group 1, 4-7 days in milk [DIM], n = 7; group 2, 90-120 DIM, n = 7; group 3, > 300 DIM, n = 7) and in cows with LDA (n = 10; group 4). D-xylose was injected into the abomasum during right flank laparotomy in cows with LDA (n = 22; group 5) and cows with AV (n = 15; group 6). The time to maximal serum D-xylose concentration was used as an index of emptying rate. The abomasal emptying rates for cows in groups 1, 2, and 3 were similar, whereas emptying was slower in cows with LDA and in cows after surgical correction of LDA or AV. The abomasal emptying rate of cows with LDA was slowed to a greater extent immediately after surgery, when compared to the rate obtained before surgery. There was no difference in abomasal emptying rate immediately after surgical correction between cows with LDA or AV. The results indicate that the increased incidence of LDA in the first month of lactation is not associated with an intrinsic decrease in abomasal emptying rate in healthy cows. Our findings also demonstrate that surgical correction further slows the emptying rate in cows with LDA.