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1

Impact of formulation excipients on human intestinal transit.  

Science.gov (United States)

The accelerating effect of polyethylene glycol 400 on small intestinal transit has been previously reported. The aim of this study was to investigate the influence of other solubility-enhancing excipient, propylene glycol, D-alpha-tocopheryl-polyethylene glycol-1,000 succinate (VitE-TPGS) and Capmul MCM, on human intestinal transit. A 5-g dose of each excipient was administered to seven healthy male subjects. Propylene glycol and VitE-TPGS were administered dissolved in 150 mL water. Capmul MCM was administered in the form of four 000 hard gelatin capsules to mask its taste and then given with 150 mL water. On a separate occasion, 150 mL water was administered as the control. Each formulation was radiolabelled with technetium-99 m to follow its transit using a gamma camera. The mean small intestinal transit times were 234, 207, 241 and 209 min for the control, propylene glycol, VitE-TPGS and Capmul MCM treatments, respectively. Although there were differences in the small intestinal transit times for the excipients investigated compared with the control, none of the results were statistically significant. Unlike polyethylene glycol 400 at the same dose of 5 g, the excipients tested (propylene glycol, VitE-TPGS and Capmul MCM) had little or no impact on small intestinal transit. PMID:16734983

Schulze, Julia D R; Ashiru, Diane A I; Khela, Mandeep K; Evans, David F; Patel, Rajesh; Parsons, Gary E; Coffin, Mark D; Basit, Abdul W

2006-06-01

2

Relationship between postprandial motor activity in the human small intestine and the gastrointestinal transit of food  

International Nuclear Information System (INIS)

Profiles for gastric emptying and colonic filling were determined in 20 normal volunteers by means of a gamma camera and dedicated minicomputer after ingestion of a radiolabeled solid meal. These were compared with intraluminal pressure activity, recorded simultaneously from three sites (each separated by 50 cm) in the small intestine by infusion manometry. Recordings were continued for at least 8 h or until all the radioactivity appeared in the colon. Colonic filling was approximately linear, occurring at an average rate of 16% of the meal residues per hour. There were significant inverse correlations (p less than 0.01) between the pressure activity in the proximal jejunum during the first 3 h after ingestion and the times taken for 50% and 80% of the meal residues to enter the colon, and direct correlations between total small intestinal pressure activity and the half-time for gastric emptying. Phase III of the interdigestive migrating motor complex appeared between 3 and 9 h after ingestion (when between 15% and 80% of the meal remained in the small intestine), but did not necessarily migrate to the next recording site until much later. The time of appearance of phase III in the proximal jejunum was directly correlated with the half-time for gastric emptying (p less than 0.05) and with the intraluminal pressure activity recorded at that site during the first 3 h after food ingestion (p less than 0.01). The time at which 80% of the meal residues had entered the colon was significantly shorter in 6 subjects, in whom a postprandial activity front appeared to migrate throughout the small bowel, compared with 13 subjects, in whom this did not occur (5.0 +/- 0.5 h vs. 7.0 +/- 0.4 h, p less than 0.01). These studies have shown that gastrointestinal transit of a solid meal is related to both fed and fasted intraluminal pressure activity in the small intestine

1984-01-01

3

Human anaerobic intestinal "rope" parasites  

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Human intestinal helminths are described in this paper. They can be over a meter long, with an irregular cylindrical shape, resembling a rope. These anaerobic intestinal "rope" parasites differ significantly from other well-known intestinal parasites. Rope parasites can leave human body with enemas, and are often mistaken for intestinal lining, feces, or decayed remains of other parasites. Rope parasites can attach to intestinal walls with suction bubbles, which later develo...

Volinsky, Alex A.; Gubarev, Nikolai V.; Orlovskaya, Galina M.; Marchenko, Elena V.

2013-01-01

4

Shiga Toxin Interaction with Human Intestinal Epithelium  

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After ingestion via contaminated food or water, enterohaemorrhagic E. coli colonises the intestinal mucosa and produces Shiga toxins (Stx). No Stx-specific secretion system has been described so far, and it is assumed that Stx are released into the gut lumen after bacterial lysis. Human intestinal epithelium does not express the Stx receptor Gb3 or other Stx binding sites, and it remains unknown how Stx cross the intestinal epithelial barrier and gain access to the systemic circulation. This ...

Stephanie Schüller

2011-01-01

5

Radioimmunoassay of human intestinal alkaline phosphatase  

International Nuclear Information System (INIS)

A new method of radioimmunoassay using the double antibody method for human intestinal alkaline phosphatase (ALP) was first elaborated. The following results were obtained: 1) In this system, the optimal antibody concentration is 10,000 times the dilution of the original anti-serum, and the optimal assay range is 0.5 to 25 ng. Enzymatic activity of 1 ng intestinal ALP is 4.1 King-Armstrong units. 2) In this system, the sera including intestinal ALP are divided to two groups. One group shows a dose response curve similar to that of purified intestinal ALP, and the other shows a lesser one. This reason is not clear. Hepatic ALP, osseous ALP and placental ALP in the sera show no response in this system. 3) In this system, the B/T value of 50 ?g of purified human placental ALP is almost equal to 1 ng of purified human intestinal ALP. Similarly, the B/T value of 50 ?g of purified human intestinal ALP is equal to almost 5 ng of purified human placental ALP. This shows that cross-reaction exists between intestinal and placental ALPs at high concentrations. (J.P.N.)

1976-01-01

6

Shiga Toxin Interaction with Human Intestinal Epithelium  

Directory of Open Access Journals (Sweden)

Full Text Available After ingestion via contaminated food or water, enterohaemorrhagic E. coli colonises the intestinal mucosa and produces Shiga toxins (Stx. No Stx-specific secretion system has been described so far, and it is assumed that Stx are released into the gut lumen after bacterial lysis. Human intestinal epithelium does not express the Stx receptor Gb3 or other Stx binding sites, and it remains unknown how Stx cross the intestinal epithelial barrier and gain access to the systemic circulation. This review summarises current knowledge about the influence of the intestinal environment on Stx production and release, Stx interaction with intestinal epithelial cells and intracellular uptake, and toxin translocation into underlying tissues. Furthermore, it highlights gaps in understanding that need to be addressed by future research.

Stephanie Schüller

2011-06-01

7

Human intestinal capillariasis in Thailand  

Directory of Open Access Journals (Sweden)

Full Text Available Intestinal capillariasis caused by Capillaria philippinensis appeared first in the Philippines and subsequently in Thailand, Japan, Iran, Egypt and Taiwan; major outbreaks have occurred in the Philippines and Thailand. This article reviews the epidemiology, history and sources of C. philippinensis infection in Thailand. The annual epidemiological surveillance reports indicated that 82 accumulated cases of intestinal capillariasis were found in Thailand from 1994-2006. That made Thailand a Capillaria-prevalent area. Sisaket, in northeast Thailand, was the first province which has reported intestinal capillariasis. Moreover, Buri Ram presented a high prevalence of intestinal capillariasis, totaling 24 cases from 1994-2006. About half of all cases have consumed raw or undercooked fish. However, even if the numbers of the intestinal capillariasis cases in Thailand is reduced, C. philippinensis infection cases are still reported. The improvement of personal hygiene, specifically avoiding consumption of undercooked fish and promoting a health education campaign are required. These strategies may minimize or eliminate C. philippinensis infection in Thailand.

Prasert Saichua, Choosak Nithikathkul, Natthawut Kaewpitoon

2008-01-01

8

Relationship between small-intestinal transit rate and intestinal absorption of 14C-labelled mannitol and 51Cr-labelled ethylenediaminetetraacetic acid in healthy subjects  

International Nuclear Information System (INIS)

Although the small-intestinal transit rate is generally considered to influence the urinary excretion of markers of intestinal permeability, no study has until now formally addressed the importance of this influence in humans. Ten healthy subjects ingested a test solution containing 99mTc-DTPA, 14C-labelled mannitol and 51Cr-EDTA. After ingestion, the small-intestinal transit rate of 99mTc-DTPA was measured with the gamma camera technique. Urine was collected to measure the excretion of absorbed 14C-mannitol and 51Cr-EDTA. Moreover, the distribution volume and plasma clearance of 14C-mannitol and 51Cr-EDTA were determined in each subject. A positive correlation was found between mean small-intestinal transit time and urinary excretion of 14C-mannitol. The study did not show any correlation between small-intestinal transit rate and urinary excretion of 51Cr-EDTA. Urinary excretion of neither 14C-mannitol nor 51Cr-EDTA was affected by distribution volume or urine volume. A positive correlation was observed between plasma clearance and urinary excretion of 14C-mannitol, whereas plasma clearance did not influence the urinary excretion of 51Cr-EDTA. Small-intestinal transit rate seems to have a significant effect on urinary excretion of 14C-mannitol, whereas small-intestinal transit rate does not influence the timed urinary excretion of 51Cr-EDTA. 25 refs., 1 fig., 2 tabs

1996-03-01

9

Human apolipoprotein B gene intestinal control region.  

Science.gov (United States)

Recently, we reported that a 315 bp enhancer, located over 55 kilobases (kb) upstream of the transcriptional start site of the human apolipoprotein B (apoB) gene, was sufficient to direct high-level expression of human apoB transgenes in mice. In this report, we expand our analysis of the distant apoB intestinal control region (ICR), by examining the function of segments in the vicinity of the 315 bp intestinal enhancer (315 IE). DNaseI hypersensitivity (DH) studies of a 4.8 kb segment from the ICR revealed three new DH sites, in addition to the previously described DH1 region present within the 315 IE. DH2 mapped to a 485 bp segment (485 IE) immediately upstream of the 315 IE that exhibited strong intestinal enhancer activity in transient transfection experiments with intestine-derived CaCo-2 cells. Within the DH2 region, an HNF-4/ARP-1 binding site was demonstrated by gel retardation experiments. A 1.8 kb segment incorporating the 485 IE was capable of driving expression of human apoB transgenes in the intestines of mice. Additionally, a third component of the apoB ICR was found about 1.2 kb downstream of the 315 IE, within a 1031 bp segment (1031 IE) that also harbored two DH sites, DH3 and DH4. This segment did not display enhancer activity but was capable of driving transgene expression in the intestine. The three components of the ICR displayed a similar pattern of apoB mRNA expression along the horizontal axis of the intestine. The previously characterized in vivo liver-specific elements of the apoB gene, namely, the second intron enhancer and the 5' upstream liver enhancer, did not play a role in intestinal expression of apoB transgenes in mice. PMID:11389586

Antes, T J; Goodart, S A; Chen, W; Levy-Wilson, B

2001-06-12

10

Alternative functional in vitro models of human intestinal epithelia  

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Physiologically relevant sources of absorptive intestinal epithelial cells are crucial for human drug transport studies. Human adenocarcinoma-derived intestinal cell lines, such as Caco-2, offer conveniences of easy culture maintenance and scalability, but do not fully recapitulate in vivo intestinal phenotypes. Additional sources of renewable physiologically relevant human intestinal cells would provide a much needed tool for drug discovery and intestinal physiology. We compared two alternat...

Kauffman, Amanda L.; Gyurdieva, Alexandra V.; Mabus, John R.; Ferguson, Chrissa; Yan, Zhengyin; Hornby, Pamela J.

2013-01-01

11

[Characteristics of microorganisms colonizing human intestine].  

Science.gov (United States)

Introduction of novel methods of microbial diagnostics has considerably broadened our conceptions on the qualitative and quantitative variety of microorganisms inhabiting human gastrointestinal tract. In this review morphological and functional properties of obligate anaerobic bacteria (bifidobacteria, lactobacilli, eubacteria, peptostreptococci, clostridia, bacteroids, fusobacteria) and facultative anaerobic microorganisms (enterobacteria, staphylococci, streptococci, yeast-like fungi of the genus Candida) capable of colonizing human intestine are briefly characterized. PMID:12525014

Efimov, B A; Volodin, N N; Kafarskaia, L I; Korshunov, V M

2002-01-01

12

Inflammation-Induced Endothelial-to-Mesenchymal Transition: A Novel Mechanism of Intestinal Fibrosis  

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In addition to mesenchymal cells, endothelial cells may contribute to fibrosis through the process of endothelial-to-mesenchymal transition (EndoMT). We investigated whether human intestinal microvascular endothelial cells (HIMEC) undergo EndoMT and contribute to fibrosis in human and experimental inflammatory bowel disease (IBD). HIMEC were exposed to TGF-?1, IL-1?, and TNF-? or supernatants of lamina propria mononuclear cells (LPMC) and evaluated for morphological, phenotypic, and functi...

Rieder, Florian; Kessler, Sean P.; West, Gail A.; Bhilocha, Shardul; La Motte, Carol; Sadler, Tammy M.; Gopalan, Banu; Stylianou, Eleni; Fiocchi, Claudio

2011-01-01

13

Gastric transit and small intestinal transit time and motility assessed by a magnet tracking system  

DEFF Research Database (Denmark)

ABSTRACT: BACKGROUND: Tracking an ingested magnet by the Magnet Tracking System MTS-1 (Motilis, Lausanne, Switzerland) is an easy and minimally-invasive method to assess gastrointestinal transit. The aim was to test the validity of MTS-1 for assessment of gastric transit time and small intestinal transit time, and to illustrate transit patterns detected by the system. Methods: A small magnet was ingested and tracked by an external matrix of 16 magnetic field sensors (4x4) giving a position defined by 5 coordinates (position: x, y, z, and angle: theta, phi). Eight healthy subjects were each investigated three times: (1) with a small magnet mounted on a capsule endoscope (PillCam); (2) with the magnet alone and the small intestine in the fasting state; and (3) with the magnet alone and the small intestine in the postprandial state. Results: Experiment (1) showed good agreement and no systematic differences between MTS-1 and capsule endoscopy when assessing gastric transit (median difference 1 min; range: 0-6 min) and small intestinal transit time (median difference 0.5 min; range: 0-52 min). Comparing experiments (1) and (2) there were no systematic differences in gastric transit or small intestinal transit when using the magnet-PillCam unit and the much smaller magnetic pill. In experiments (2) and (3), short bursts of very fast movements lasting less than 5% of the time accounted for more than half the distance covered during the first two hours in the small intestine, irrespective of whether the small intestine was in the fasting or postprandial state. The mean contraction frequency in the small intestine was significantly lower in the fasting state than in the postprandial state (9.90 min-1 vs. 10.53 min-1) (p=0.03). Conclusion: MTS-1 is reliable for determination of gastric transit and small intestinal transit time. It is possible to distinguish between the mean contraction frequency of small intestine in the fasting state and in the postprandial state.

Worsoe, Jonas; Fynne, Lotte

2011-01-01

14

Cholesterol esterase activity of human intestinal mucosa  

International Nuclear Information System (INIS)

It has been suggested that cholesterol absorption in humans is dependent on bile acid pool composition and that expansion of the cholic acid pool size is followed by an increase of the absorption values. Similar observations were reported in rats. In the present study, therefore, the authors investigated some general properties of human intestinal cholesterol esterase, with particular emphasis on the effect of bile acids on this enzymatic activity. Twenty-nine segments of small intestine were taken during operations; the enzymatic activity was studied by using mucosal homogenate as a source of enzyme and oleic acid, cholesterol, and 14C-labeled cholesterol as substrates. The time-activity relationship was linear within the first two hours; optimal pH for esterification ranged between 5 and 6.2. There was little difference between the esterifying activity of the jejunal and ileal mucosa. Esterification of cholesterol was observed with all the investigated fatty acids but was maximal with oleic acid. Bile acids did not affect cholesterol esterase activity when present in the incubation mixture at 0.1 and 1.0 mM; the enzymatic activity, however, was significantly inhibited when bile acids were added at 20 mM. In conclusion, this study has shown that the human intestinal mucosa possesses a cholesterol esterase activity; at variance with the rat, however, the human enzyme does not seem to be stimulated by trihydroxy bile acids

1985-01-01

15

Increased intestinal marker absorption due to regional permeability changes and decreased intestinal transit during sepsis in the rat  

International Nuclear Information System (INIS)

The intestinal barrier properties are impaired during inflammation and sepsis, but the mechanisms behind this are unknown and were therefore investigated during experimental sepsis in rats. The different-sized intestinal absorption markers "5"1Cr-labeled ethylenediaminetetraacetic acid (EDTA) and ovalbumin were gavaged to rats made septic by intra-abdominal bacterial implantation and to sham-operated rats. Regional tissue permeability was measured in diffusion chambers, and intestinal transit was evaluated by intestinal accumulation of gavaged "5"1Cr-EDTA. In comparison with the sham-operated rats, septic rats had higher "5"1Cr-EDTA levels in blood and urine and showed a prolonged intestinal transit. Septic rats also had a lower tissue permeability to both markers in the small intestines but higher permeability to ovalbumin in the colon. Rats receiving morphine to decrease intestinal motility showed similar changes, with a decreased intestinal transit and increased marker absorption. Thr results suggest that the increased intestinal absorption during sepsis was due to regional permeability changes and prolonged intestinal transit. 38 refs., 4 figs., 2 tabs

1994-11-01

16

Increased intestinal marker absorption due to regional permeability changes and decreased intestinal transit during sepsis in the rat  

Energy Technology Data Exchange (ETDEWEB)

The intestinal barrier properties are impaired during inflammation and sepsis, but the mechanisms behind this are unknown and were therefore investigated during experimental sepsis in rats. The different-sized intestinal absorption markers {sup 51}Cr-labeled ethylenediaminetetraacetic acid (EDTA) and ovalbumin were gavaged to rats made septic by intra-abdominal bacterial implantation and to sham-operated rats. Regional tissue permeability was measured in diffusion chambers, and intestinal transit was evaluated by intestinal accumulation of gavaged {sup 51}Cr-EDTA. In comparison with the sham-operated rats, septic rats had higher {sup 51}Cr-EDTA levels in blood and urine and showed a prolonged intestinal transit. Septic rats also had a lower tissue permeability to both markers in the small intestines but higher permeability to ovalbumin in the colon. Rats receiving morphine to decrease intestinal motility showed similar changes, with a decreased intestinal transit and increased marker absorption. Thr results suggest that the increased intestinal absorption during sepsis was due to regional permeability changes and prolonged intestinal transit. 38 refs., 4 figs., 2 tabs.

Wang, Q.; Pantzar, N.; Jeppson, B.; Westroem, B.R.; Karlsson, B.W. [Univ. of Lund (Sweden)

1994-11-01

17

Neutrophil depletion attenuates human intestinal reperfusion injury.  

Science.gov (United States)

Intestinal ischemia/reperfusion injury (I/R) results from reactive oxygen metabolites generated by the xanthine oxidase system and activated neutrophils (PMN). In animal models, removing PMN from initial reperfusate has consistently decreased tissue injury. This experiment was designed to test this potential clinical treatment in human bowel subjected to I/R. The extent of reperfusion injury was assessed by measuring the activity of mucosal alkaline phosphatase (A phi), which is a specific marker of reperfusion injury. Human small intestine (n = 13) obtained at the time of organ harvest for transplantation was perfused for 60 min on an ex vivo perfusion circuit. Reperfusate consisted of autologous blood passed through a leukocyte filter (n = 6) or unfiltered blood (n = 7). Control intestine was sampled at harvest, after transport to the lab on ice (cold ischemia), and after 60 min warm ischemia. Mucosa was homogenized and assayed for A phi activity by cleavage of p-nitrophenyl phosphate. A phi activity (nmole/mg/min) was not decreased after either cold (774 +/- 37) or warm (753 +/- 40) ischemia compared to freshly harvested bowel (770 +/- 51). Both reperfused segments showed a significant decrease in A phi activity compared to controls (P < 0.05); however, reperfusion with leukocyte-filtered blood attenuated the decrease in enzyme activity compared to unfiltered blood (327 +/- 30 vs 506 +/- 25, P < 0.05), constituting an apparent reduction in injury of 35%. The observation that the severity of reperfusion injury was decreased by removal of PMN from the reperfusate demonstrates the efficacy of this strategy in human intestine for the first time. PMID:8041137

Sisley, A C; Desai, T; Harig, J M; Gewertz, B L

1994-07-01

18

Lower serum oestrogen concentrations associated with faster intestinal transit.  

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Increased fibre intake has been shown to reduce serum oestrogen concentrations. We hypothesized that fibre exerts this effect by decreasing the time available for reabsorption of oestrogens in the colon. We tested this in volunteers by measuring changes in serum oestrogen levels in response to manipulation of intestinal transit times with senna and loperamide, then comparing the results with changes caused by wheat bran. Forty healthy premenopausal volunteers were placed at random into one of...

1997-01-01

19

Generating human intestinal tissue from pluripotent stem cells in vitro  

Science.gov (United States)

We describe a protocol to generate 3-dimensional human intestinal tissue (called organoids) in vitro from human pluripotent stem cells. To generate intestinal organoids, pluripotent stem cells are first differentiated into FOXA2+/SOX17+ endoderm by treating the cells with ActivinA for 3 days. Following endoderm induction, the pluripotent stem cells are patterned into CDX2+ mid/hindgut tissue using FGF4 and WNT3a. During this patterning step, 3-dimensional mid/hindgut spheroids bud from the monolayer epithelium attached to the tissue culture dish. The 3-dimensional spheroids are further cultured in matrigel along with pro-intestinal growth factors, and proliferate and expand over 1–3 months to give rise to intestinal tissue, complete with intestinal mesenchyme and epithelium consisting of all of the major intestinal cell types. To date, this is the only method to efficiently direct differentiation of human pluripotent stem cells into 3-dimensional human intestinal tissue in vitro.

McCracken, Kyle W.; Howell, Jonathan C.; Wells, James M.; Spence, Jason R.

2013-01-01

20

Small intestinal transit of spherical particles in the active rat  

International Nuclear Information System (INIS)

Reproducible measurements of small intestine transit for spherical particles of 0.5 ? to 1 mm diameter, have been accomplished in the conscious rat. A short cannula of polyethylene is surgically implanted into the duodenum and exists through the abdominal wall. After recovery, a bolus of saline containing colored or isotopically labeled particulate material and an internal standard of NaCr"5"1O_4 is introduced with a modified pipette tip that snugly fills the cannula to prevent back flow. The rats eat and drink during the transit period and are maintained on a reversed light cycle so that transit is measured during their physically active period. Glass microspheres of 1mm, 500 ?, and 50 ? were followed at 30 min, 1 hr, and 2 hr intervals by opening the intestine and photographing 1 cm segments along its length. Polymer beads of 500 ?, 125 ?, and 70 ? were labeled with "1"2"5I and located by freezing the exteriorized intestine and counting 1 cm segments in a gamma counter. Movement of the fluid bolus as detected by NaCr"5"1O_4 was reproducible with the fluid front moving through 59%, 73%, and 81% of the length at 30 min, 1 hr, and 2 hr. One millimeter to 125 ? glass and polymer beads moved with the fluid bolus. Evidence for separation of the fluid phase and particles under ? 100 ? is accumulating. It is hypothesized that small particles under a critical size may become lodged in the mucus lining of the intestinal wall

1986-03-05

 
 
 
 
21

Alternative Functional In Vitro Models of Human Intestinal Epithelia  

Directory of Open Access Journals (Sweden)

Full Text Available Physiologically relevant sources of absorptive intestinal epithelial cells are crucial for human drug transport studies. Human adenocarcinoma-derived intestinal cell lines, such as Caco-2, offer conveniences of easy culture maintenance and scalability, but do not fully recapitulate in vivo intestinal phenotypes. Additional sources of renewable physiologically relevant human intestinal cells would provide a much needed tool for drug discovery and intestinal physiology. We sought to evaluate and compare two alternative sources of human intestinal cells, commercially available primary human intestinal epithelial cells (hInEpCs and induced pluripotent stem cell (iPSC-derived intestinal cells to Caco-2, for use in in vitro transwell monolayer intestinal transport assays. To achieve this for iPSC-derived cells, our previously described 3-dimensional intestinal organogenesis method was adapted to transwell differentiation. Intestinal cells were assessed by marker expression through immunocytochemical and mRNA expression analyses, monolayer integrity through Transepithelial Electrical Resistance (TEER measurements and molecule permeability, and functionality by taking advantage the well-characterized intestinal transport mechanisms. In most cases, marker expression for primary hInEpCs and iPSC-derived cells appeared to be as good as or better than Caco-2. Furthermore, transwell monolayers exhibited high TEER with low permeability. Primary hInEpCs showed molecule efflux indicative of P-glycoprotein transport. Primary hInEpCs and iPSC-derived cells also showed neonatal Fc receptor-dependent binding of immunoglobulin G variants. Primary hInEpCs and iPSC-derived intestinal cells exhibit expected marker expression and demonstrate basic functional monolayer formation, similar to or better than Caco-2. These cells could offer an alternative source of human intestinal cells for understanding normal intestinal epithelial physiology and drug transport.

AmandaLKauffman

2013-07-01

22

[Intestinal transit time in bilio-pancreatic bypass].  

Science.gov (United States)

Transit times were evaluated in 23 obese subjects before and 1,4 and 12 months after biliopancreatic by-pass. A modified version of the method of Hinton et al. was used to determine emptying of the stomach and partial and total transit times. Emptying of the stomach was normal preoperatively. After surgery, it was almost immediate, except in two subjects with stomitis. Both transit times were virtually unchanged. Since the segment between the stomach and the ileocaecal valve is only half as long as in the normal subject, the results show that the by-pass leads to a slowing of transit that concerns the small intestine only, is quickly established, and does not change in the course of time. Evaluation of the altered anatomical and functional situation, and the absence of a correlation between the long-term behaviour of transit times on one hand and of lipid malabsorption and weight loss on the other-hand, suggest that a slower transit time must not be regarded as a compensation mechanism, except insofar as it restricts the degree of malabsorption set up immediately after surgery. Preliminary studies of enterohormonal changes following the by-pass indicate that increased glucagon and decreased motiline values are mainly responsible for slower transit times. PMID:6779238

Bonalumi, U; Moresco, L; Gianetta, E; Civalleri, D; De Cata, T; Brignole, E; Scopinaro, N

23

Inflammation-induced endothelial-to-mesenchymal transition: a novel mechanism of intestinal fibrosis.  

Science.gov (United States)

In addition to mesenchymal cells, endothelial cells may contribute to fibrosis through the process of endothelial-to-mesenchymal transition (EndoMT). We investigated whether human intestinal microvascular endothelial cells (HIMEC) undergo EndoMT and contribute to fibrosis in human and experimental inflammatory bowel disease (IBD). HIMEC were exposed to TGF-?1, IL-1?, and TNF-? or supernatants of lamina propria mononuclear cells (LPMC) and evaluated for morphological, phenotypic, and functional changes compatible with EndoMT. Genomic analysis was used to identify transcription factors involved in the transformation process. Evidence of in situ and in vivo EndoMT was sought in inflamed human and murine intestine. The combination of TGF-?1, IL-1? and TNF-?, or activated LPMC supernatants induced morphological and phenotypic changes consistent with EndoMT with a dominant effect by IL-1. These changes persisted after removal of the inducing agents and were accompanied by functional loss of acetylated LDL-uptake and migratory capacity, and acquisition of de novo collagen synthesis capacity. Sp1 appeared to be the main transcriptional regulator of EndoMT. EndoMT was detected in microvessels of inflammatory bowel disease (IBD) mucosa and experimental colonic fibrosis of Tie2-green fluorescent protein (GFP) reporter-expressing mice. In conclusion, chronic inflammation induces transdifferentiation of intestinal mucosal microvascular cells into mesenchymal cells, suggesting that the intestinal microvasculature contributes to IBD-associated fibrosis through the novel process of EndoMT. PMID:21945322

Rieder, Florian; Kessler, Sean P; West, Gail A; Bhilocha, Shardul; de la Motte, Carol; Sadler, Tammy M; Gopalan, Banu; Stylianou, Eleni; Fiocchi, Claudio

2011-11-01

24

Molecular Epidemiology of Human Intestinal Amoebas in Iran  

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Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, m...

Hooshyar, H.; Rostamkhani, P.; Rezaian, M.

2012-01-01

25

Metabolism of hibifolin by human intestinal bacteria.  

Science.gov (United States)

Hibifolin, the highest-content bioactive flavonoid of the flowers of Abelmoschus manihot, was incubated with human intestinal bacteria, and four metabolites (1-4) were obtained from the incubated solution by chromatographic methods. The structures of the four metabolites were elucidated as gossypetin 8-O-beta-D-4''-deoxy- Delta(4'')-glucuropyranoside (1), gossypetin (2), quercetin (3), and 8-methoxy-quercetin (4), respectively, on the basis of UV, NMR, and MS data. Metabolite 1 was obtained as a new compound with a specific beta-D-4''-deoxy-Delta(4'')-glucuropyranosyl moiety, which was formed through a unique and novel metabolic pathway that has not been reported previously. PMID:19235125

Xu, Tong-Tong; Yang, Xiu-Wei; Wang, Bin; Xu, Wei; Zhao, Yu-Ying; Zhang, Qing-Ying

2009-04-01

26

Inhibition of human intestinal ?-glucosidases by calystegines.  

Science.gov (United States)

Calystegines are polyhydroxylated nortropane alkaloids found in Convolvulaceae, Solanaceae, and other plant families. These plants produce common fruits and vegetables. The calystegine structures resemble sugars and suggest interaction with enzymes of carbohydrate metabolism. Maltase and sucrase are ?-glucosidases contributing to human carbohydrate degradation in the small intestine. Inhibition of these enzymes by orally administered drugs is one option for treatment of diabetes mellitus type 2. In this study, inhibition of maltase and sucrase by calystegines A3 and B2 purified from potatoes was investigated. In silico docking studies confirmed binding of both calystegines to the active sites of the enzymes. Calystegine A3 showed low in vitro enzyme inhibition; calystegine B2 inhibited mainly sucrose activity. Both compounds were not transported by Caco-2 cells indicating low systemic availability. Vegetables rich in calystegine B2 should be further investigated as possible components of a diet preventing a steep increase in blood glucose after a carbohydrate-rich meal. PMID:23697377

Jockovi?, Nebojša; Fischer, Wiebke; Brandsch, Matthias; Brandt, Wolfgang; Dräger, Birgit

2013-06-12

27

Combinatorial QSAR modeling of human intestinal absorption.  

Science.gov (United States)

Intestinal drug absorption in humans is a central topic in drug discovery. In this study, we use a broad selection of machine learning and statistical methods for the classification and numerical prediction of this key end point. Our data set is based on a selection of 458 small druglike compounds with FDA approval. Using easily available tools, we calculated one- to three-dimensional physicochemical descriptors and used various methods of feature selection (best-first backward selection, correlation analysis, and decision tree analysis). We then used decision tree induction (DTI), fragment-based lazy-learning (LAZAR), support vector machine classification, multilayer perceptrons, random forests, k-nearest neighbor and Naïve Bayes analysis to model absorption ratios and binary classification (well-absorbed and poorly absorbed compounds). Best performance for classification was seen with DTI using the chi-squared analysis interaction detector (CHAID) algorithm, yielding corrected classification rate of 88% (Matthews correlation coefficient of 75%). In numeric predictions, the multilayer perceptron performed best, achieving a root mean squared error of 25.823 and a coefficient of determination of 0.6. In line with current understanding is the importance of descriptors such as lipophilic partition coefficients (log P) and hydrogen bonding. However, we are able to highlight the utility of gravitational indices and moments of inertia, reflecting the role of structural symmetry in oral absorption. Our models are based on a diverse data set of marketed drugs representing a broad chemical space. These models therefore contribute substantially to the molecular understanding of human intestinal drug absorption and qualify for a generalized use in drug discovery and lead optimization. PMID:21142073

Suenderhauf, Claudia; Hammann, Felix; Maunz, Andreas; Helma, Christoph; Huwyler, Jörg

2011-02-01

28

A Revised Model for Dosimetry in the Human Small Intestine  

International Nuclear Information System (INIS)

A new model for an adult human gastrointestinal tract (GIT) has been developed for use in internal dose estimations to the wall of the GIT and to the other organs and tissues of the body from radionuclides deposited in the lumenal contents of the five sections of the GIT. These sections were the esophasgus, stomach, small intestine, upper large intestine, and the lower large intestine. The wall of each section was separated from its lumenal contents

2005-01-01

29

Impaired transit and tolerance of intestinal gas in the irritable bowel syndrome  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background—Patients with irritable bowel syndrome (IBS) frequently complain of excessive gas but their fasting volume of intestinal gas is apparently normal. We hypothesised that the pathophysiological mechanism involved may be impairment of intestinal gas transit. Aim—To investigate intestinal gas transit and tolerance in IBS patients compared with healthy subjects. Methods—A gas mixture (N2, O2, and CO2 in venous proportions) was infused into the jejunum of 20 patients with ...

Serra, J.; Azpiroz, F.; Malagelada, J.

2001-01-01

30

Unregulated smooth-muscle myosin in human intestinal neoplasia  

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A recent study described a recessive ATPase activating germ-line mutation in smooth-muscle myosin (smmhc/myh11) underlying the zebrafish meltdown (mlt) phenotype. The mlt zebrafish develops intestinal abnormalities reminiscent of human Peutz–Jeghers syndrome (PJS) and juvenile polyposis (JP). To examine the role of MYH11 in human intestinal neoplasia, we searched for MYH11 mutations in patients with colorectal cancer (CRC), PJS and JP. We found somatic protein-elongating frameshift mutation...

Alhopuro, Pia; Phichith, Denis; Tuupanen, Sari; Sammalkorpi, Heli; Nybondas, Miranda; Saharinen, Juha; Robinson, James P.; Yang, Zhaohui; Chen, Li-qiong; Orntoft, Torben; Mecklin, Jukka-pekka; Ja?rvinen, Heikki; Eng, Charis; Moeslein, Gabriela; Shibata, Darryl

2008-01-01

31

Human intestinal spirochetes are distinct from Serpulina hyodysenteriae.  

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Twenty-nine intestinal spirochetes isolated from Australian aboriginal children and six strains from Italian adults (HRM1, -2, -4, -5, -7, and -14) were genetically examined at 15 enzyme loci by using multilocus enzyme electrophoresis. Results were compared with those previously obtained for 188 porcine intestinal spirochetes. DNA from human strain HRM7 and porcine strain Serpulina hyodysenteriae P18A were also radioactively labeled and hybridized with DNA from 12 other human and porcine inte...

Lee, J. I.; Mclaren, A. J.; Lymbery, A. J.; Hampson, D. J.

1993-01-01

32

Obstructive cholestasis alters intestinal transit in mice: role of opioid system.  

Science.gov (United States)

Acute cholestasis is associated with increased activity of the endogenous opioid system. It is also known that opioid receptor agonists like morphine decrease the intestinal transit. The purpose of the present study was to investigate the effect of cholestasis on the small intestine transit and the possible involvement of opioid system in this phenomenon in mice. Cholestasis was induced by bile duct-ligation and intestinal transit was measured with charcoal meal and calculation of percent of transit through small intestine. The effect of chronic administration of naltrexone and acute pretreatment with morphine on intestinal transit was evaluated in bile duct-ligated (BDL) as well as unoperated (CTL) and sham-operated (SHAM) animals. The plasma alkaline phosphatase and alanine aminotransferase activities were also measured. A significant decrease in small intestine transit (%transit) was observed in BDL mice compared to SHAM animals, which was prominent even after 24 h of cholestasis. Chronic pretreatment with an opioid receptor antagonist, naltrexone, (10 mg/kg, i.p for 2, 4 or 6 days) completely restored the cholestasis-induced decrease in %transit to that of control animals. Although the acute administration of morphine (2 mg/kg, s.c.) 20 min before charcoal feeding caused a significant decrease in the intestinal transit of CTL and SHAM animals, it did not decrease the %transit of BDL animals on the day 5 after operation. Our findings show that acute cholestasis is associated with a prominent decrease in small intestine transit in mice and opioid receptors maybe involved in this phenomenon. PMID:15530502

Ghaffari, Kamyar; Savadkuhi, Shahab Tour; Honar, Hooman; Riazi, Kiarash; Shafaroodi, Hamed; Moezi, Leila; Ebrahimkhani, Mohammad Reza; Tahmasebi, Mohammad Saeid Radjabzadeh; Dehpour, Ahmad Reza

2004-12-10

33

Prostacyclin inhibits gastric emptying and small-intestinal transit in rats and dogs  

International Nuclear Information System (INIS)

Prostacyclin (PGI2) antagonizes 16,16-dimethyl prostaglandin E2-induced diarrhea in rats, presumably by inhibiting the fluid accumulation of ''enteropooling'' in the small intestine. The effect of PGI2 on gastric emptying, small intestinal transit, and colonic transit was examined in rats and dogs to determine if interference with propulsion might also contribute to the antidiarrheal properties of this compound. Rats implanted with chronic duodenal cannulas were given subcutaneous PGI2 (0.1-1000 microgram/kg) followed 10 min later by intragastric 2Cr and a visually detectable duodenal transit marker. Forty-five minutes later, the animals were killed. Subcutaneous PGI2 inhibited gastric emptying maximally at 10 micrograms/kg. Small-intestinal transit was significantly decreased at 50 micrograms/kg and almost completely suppressed at 1.0 mg/kg. Subcutaneous naloxone (0.5 mg/kg) given 10 min before and 20 min after subcutaneous PGI2 administration did not block PGI2's effects. Intravenous or oral PGI2, had none of these effects. Small intestinal transit was only decreased by PGI2 infusion, suggesting that this parameter was more sensitive to a sustained blood level than gastric emptying. Hourly injections of subcutaneous PGI2 (0.5 mg/kg) had no effect on rat colonic transit measured over a 3-h period after deposition of the transit marker through a colonic cannula in a manner similar to that described for small-intestinal transit above. Small-intestinal transit was also measured in dogs given a barium suspension through a chronic duodenal cannula. In vehicle-treated dogs, barium reached the cecal area in an average of 2.8 h after instillation. In PGI2-treated dogs, barium never reached the cecum in the 5-h examination period. Thus, PGI2 inhibits gastric emptying in rat and small-intestinal transit in rat and dog but has no effect on rat colonic transit

1984-01-01

34

Intestinal pathology in human metagonimiasis with ultrastructural observations of parasites.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A human case of intestinal metagonimiasis that was incidentally found during the histological examination of a resected segment of jejunum was described. The small adults trematode of Metagonimus yokogawai were found free in jejunal lumen as well as impacted in intervillous spaces. Histologically intestinal lesions were massive lymphoplasmacytic and eosinophilic infiltration in stroma, erosion of neanby enterocytes, goblet cell depletion and occasional villous edema. Scanning electron microsc...

1988-01-01

35

Effect of heat stress on intestinal barrier function of human intestinal epithelial Caco-2 cells  

Directory of Open Access Journals (Sweden)

Full Text Available Objective?To investigate the heat stress-induced dysfunction of intestinal barrier including intestinal tight junction and apoptosis of epithelial cells. Methods?Human intestinal epithelial Caco-2 cell monolayers, serving as the intestinal barrier model, were exposed to different temperature (37-43? for designated time. Transepithelial electrical resistance (TEER and horseradish peroxidase (HRP flux permeability were measured to evaluate barrier integrity. Level of tight junction (TJ protein occludin was analyzed by Western blotting. Cell apoptosis rate was determined using Annexin V-FITC/PI kit by flow cytometry. Results?Compared with the 37? group, TEER lowered and the permeability for HRP increased significantly after heat exposure (P<0.01 in 39?, 41? and 43? groups. The expression of occludin increased when the temperature was elevated from 37? to 41?, and it reached the maximal level at 41?. However, its expression gradually decreased with passage of time at 43?. Cell apoptosis was enhanced with elevation of the temperature (P?0.05 or P?0.01. Conclusion?Heat stress can induce damage to tight junction and enhance apoptosis of epithelial cells, thus causing dysfunction of intestinal epithelial barrier.

Gui-zhen XIAO

2013-07-01

36

Intestinal-fatty acid binding protein and lipid transport in human intestinal epithelial cells  

International Nuclear Information System (INIS)

Intestinal-fatty acid binding protein (I-FABP) is a 14-15 kDa cytoplasmic molecule highly expressed in the enterocyte. Although different functions have been proposed for various FABP family members, the specific function of I-FABP in human intestine remains unclear. Here, we studied the role of I-FABP in molecularly modified normal human intestinal epithelial cells (HIEC-6). cDNA transfection resulted in 90-fold I-FABP overexpression compared to cells treated with empty pQCXIP vector. The high-resolution immunogold technique revealed labeling mainly in the cytosol and confirmed the marked phenotype abundance of I-FABP in cDNA transfected cells. I-FABP overexpression was not associated with alterations in cell proliferation and viability. Studies using these transfected cells cultured with [14C]oleic acid did not reveal higher efficiency in de novo synthesis or secretion of triglycerides, phospholipids, and cholesteryl esters compared to cells treated with empty pQCXIP vector only. Similarly, the incubation with [35S]methionine did not disclose a superiority in the biogenesis of apolipoproteins (apo) A-I, A-IV, B-48, and B-100. Finally, cells transfected with I-FABP did not exhibit an increased production of chylomicrons, VLDL, LDL, and HDL. Our observations establish that I-FABP overexpression in normal HIEC-6 is not related to cell proliferation, lipid esterification, apo synthesis, and lipoprotein assembly, and, therefore, exclude its role in intestinal fat transport

2006-01-06

37

Effect of thienorphine on intestinal transit and isolated guinea-pig ileum contraction  

Directory of Open Access Journals (Sweden)

Full Text Available AIM: To evaluate the effect of thienorphine on small intestinal transit in vivo and on guinea-pig ileum (GPI contraction in vitro. METHODS: The effects of thienorphine on intestinal transit were examined in mice and in isolated GPI. Buprenorphine and morphine served as controls. The distance traveled by the head of the charchol and the total length of the intestine were measured in vivo. Gastrointestinal transit was expressed as a percentage of the distance traveled by the head of the marker relative to the total length of the small intestine. The isolated GPI preparations were connected to an isotonic force transducer and equilibrated for at least 1 h before exposure to drugs. Acetylcholine was used for muscle stimulation. RESULTS: Thienorphine (0.005-1.0 mg/kg, ig or buprenorphine (0.005-1.0 mg/kg, sc dose-dependently significantly inhibited gut transit compared with saline. Thienorphine inhibited gut transit less than buprenorphine. The maximum inhibition by thienorphine on the intestinal transit was 50%-60%, whereas the maximum inhibition by morphine on gut transit was about 100%. Thienorphine also exhibited less inhibition on acetylcholine-induced contraction of GPI, with a maximum inhibition of 65%, compared with 93% inhibition by buprenorphine and 100% inhibition by morphine. Thienorphine induced a concentration-dependent decrease in the basal tonus of spontaneous movement of the GPI, the effect of which was weaker than that with buprenorphine. The duration of the effect of thienorphine on the GPI was longer than that with buprenorphine. CONCLUSION: Thienorphine had less influence, but a longer duration of action on GPI contraction and moderately inhibited intestinal transit.

Pei-Lan Zhou

2013-01-01

38

Quantitation of small intestinal permeability during normal human drug absorption  

Science.gov (United States)

Background Understanding the quantitative relationship between a drug’s physical chemical properties and its rate of intestinal absorption (QSAR) is critical for selecting candidate drugs. Because of limited experimental human small intestinal permeability data, approximate surrogates such as the fraction absorbed or Caco-2 permeability are used, both of which have limitations. Methods Given the blood concentration following an oral and intravenous dose, the time course of intestinal absorption in humans was determined by deconvolution and related to the intestinal permeability by the use of a new 3 parameter model function (“Averaged Model” (AM)). The theoretical validity of this AM model was evaluated by comparing it to the standard diffusion-convection model (DC). This analysis was applied to 90 drugs using previously published data. Only drugs that were administered in oral solution form to fasting subjects were considered so that the rate of gastric emptying was approximately known. All the calculations are carried out using the freely available routine PKQuest Java (http://www.pkquest.com) which has an easy to use, simple interface. Results Theoretically, the AM permeability provides an accurate estimate of the intestinal DC permeability for solutes whose absorption ranges from 1% to 99%. The experimental human AM permeabilities determined by deconvolution are similar to those determined by direct human jejunal perfusion. The small intestinal pH varies with position and the results are interpreted in terms of the pH dependent octanol partition. The permeability versus partition relations are presented separately for the uncharged, basic, acidic and charged solutes. The small uncharged solutes caffeine, acetaminophen and antipyrine have very high permeabilities (about 20 x 10-4?cm/sec) corresponding to an unstirred layer of only 45??m. The weak acid aspirin also has a large AM permeability despite its low octanol partition at pH?7.4, suggesting that it is nearly completely absorbed in the first part of the intestine where the pH is about 5.4. Conclusions The AM deconvolution method provides an accurate estimate of the human intestinal permeability. The results for these 90 drugs should provide a useful benchmark for evaluating QSAR models.

2013-01-01

39

Exopolysaccharides Produced by Intestinal Bifidobacterium Strains Act as Fermentable Substrates for Human Intestinal Bacteria ?  

Science.gov (United States)

Eleven exopolysaccharides (EPS) isolated from different human intestinal Bifidobacterium strains were tested in fecal slurry batch cultures and compared with glucose and the prebiotic inulin for their abilities to act as fermentable substrates for intestinal bacteria. During incubation, the increases in levels of short-chain fatty acids (SCFA) were considerably more pronounced in cultures with EPS, glucose, and inulin than in controls without carbohydrates added, indicating that the substrates assayed were fermented by intestinal bacteria. Shifts in molar proportions of SCFA during incubation with EPS and inulin caused a decrease in the acetic acid-to-propionic acid ratio, a possible indicator of the hypolipidemic effect of prebiotics, with the lowest values for this parameter being obtained for EPS from the species Bifidobacterium longum and from Bifidobacterium pseudocatenulatum strain C52. This behavior was contrary to that found with glucose, a carbohydrate not considered to be a prebiotic and for which a clear increase of this ratio was obtained during incubation. Quantitative real-time PCR showed that EPS exerted a moderate bifidogenic effect, which was comparable to that of inulin for some polymers but which was lower than that found for glucose. PCR-denaturing gradient gel electrophoresis of 16S rRNA gene fragments using universal primers was employed to analyze microbial groups other than bifidobacteria. Changes in banding patterns during incubation with EPS indicated microbial rearrangements of Bacteroides and Escherichia coli relatives. Moreover, the use of EPS from B. pseudocatenulatum in fecal cultures from some individuals accounted for the prevalence of Desulfovibrio and Faecalibacterium prausnitzii, whereas incubation with EPS from B. longum supported populations close to Anaerostipes, Prevotella, and/or Oscillospira. Thus, EPS synthesized by intestinal bifidobacteria could act as fermentable substrates for microorganisms in the human gut environment, modifying interactions among intestinal populations.

Salazar, Nuria; Gueimonde, Miguel; Hernandez-Barranco, Ana Maria; Ruas-Madiedo, Patricia; de los Reyes-Gavilan, Clara G.

2008-01-01

40

Metabolism of nitropolycyclic aromatic hydrocarbons by human intestinal microflora  

Energy Technology Data Exchange (ETDEWEB)

Anaerobic bacterial suspensions from human and rat feces and intestinal contents, and pure cultures of anaerobic bacteria metabolized 1-nitropyrene and 6-nitrobenzo(a)pyrene to 1-aminopyrene and 6-aminobenzo(a)pyrene, respectively. The metabolites were isolated by reversed-phase high performance liquid chromatography and identified by comparison of their chromatographic and mass spectral properties with those of authentic compounds. The results suggest that anaerobic intestinal bacteria could play a significant role in the metabolism of potentially carcinogenic nitropolycyclic aromatic hydrocarbons. 28 references, 4 figures, 1 table.

Cerniglia, C.E.; Howard, P.C.; Fu, P.P.; Franklin, W.

1984-08-30

 
 
 
 
41

Development stages of the "rope" human intestinal parasite  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper describes the five development stages of the rope human parasite. Rope parasites have been discovered as a result of cleansing enemas. Parasite adult stages live in human gastro-intestinal tract and are anaerobic. They move inside the body by releasing gas bubbles utilizing jet propulsion. Rope parasites look like a rope, and can be over a meter long. It takes tens of years for them to fully develop into mature species (fifth stage). The fourth stage looks similar...

Volinsky, Alex A.; Gubarev, Nikolai V.; Orlovskaya, Galina M.; Marchenko, Elena V.

2013-01-01

42

Molecular Epidemiology of Human Intestinal Amoebas in Iran  

Directory of Open Access Journals (Sweden)

Full Text Available Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran.

M Rezaian

2012-09-01

43

Molecular epidemiology of human intestinal amoebas in iran.  

Science.gov (United States)

Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran. PMID:23193500

Hooshyar, H; Rostamkhani, P; Rezaian, M

2012-01-01

44

Prostacyclin inhibits gastric emptying and small-intestinal transit in rats and dogs  

Energy Technology Data Exchange (ETDEWEB)

Prostacyclin (PGI2) antagonizes 16,16-dimethyl prostaglandin E2-induced diarrhea in rats, presumably by inhibiting the fluid accumulation of ''enteropooling'' in the small intestine. The effect of PGI2 on gastric emptying, small intestinal transit, and colonic transit was examined in rats and dogs to determine if interference with propulsion might also contribute to the antidiarrheal properties of this compound. Rats implanted with chronic duodenal cannulas were given subcutaneous PGI2 (0.1-1000 microgram/kg) followed 10 min later by intragastric /sup 2/Cr and a visually detectable duodenal transit marker. Forty-five minutes later, the animals were killed. Subcutaneous PGI2 inhibited gastric emptying maximally at 10 micrograms/kg. Small-intestinal transit was significantly decreased at 50 micrograms/kg and almost completely suppressed at 1.0 mg/kg. Subcutaneous naloxone (0.5 mg/kg) given 10 min before and 20 min after subcutaneous PGI2 administration did not block PGI2's effects. Intravenous or oral PGI2, had none of these effects. Small intestinal transit was only decreased by PGI2 infusion, suggesting that this parameter was more sensitive to a sustained blood level than gastric emptying. Hourly injections of subcutaneous PGI2 (0.5 mg/kg) had no effect on rat colonic transit measured over a 3-h period after deposition of the transit marker through a colonic cannula in a manner similar to that described for small-intestinal transit above. Small-intestinal transit was also measured in dogs given a barium suspension through a chronic duodenal cannula. In vehicle-treated dogs, barium reached the cecal area in an average of 2.8 h after instillation. In PGI2-treated dogs, barium never reached the cecum in the 5-h examination period. Thus, PGI2 inhibits gastric emptying in rat and small-intestinal transit in rat and dog but has no effect on rat colonic transit.

Ruwart, M.J.; Rush, B.D.

1984-08-01

45

Síndrome estreñimiento: métodos para medir la velocidad de tránsito intestinal / Constipation syndrome: methods for measuring the speed of intestinal transit  

Scientific Electronic Library Online (English)

Full Text Available SciELO Peru | Language: Spanish Abstract in spanish En el presente artículo, recuerdo lo que presenté, en un simposio llevado a cabo en nuestra Sociedad sobre el síndrome estreñimiento, en relación con la definición y los factores determinantes de este síndrome, y, además, con los métodos que hemos creado para medir en forma fisiológica la velocidad [...] del tránsito intestinal, especialmente colónico. Abstract in english In the present article, I remind what I presented, in a symposium performed in our Society on the constipation syndrome, in relation with the definition and the determinant factores of this syndrome, and, in addition, with the methods we have created to determine physiologically the velocity of the [...] intestinal transit, specially colonic.

Raúl, León-Barúa.

46

Central role of IL-6 and MMP-1 for cross talk between human intestinal mast cells and human intestinal fibroblasts.  

Science.gov (United States)

Mast cells (MC) are key effector cells in allergic reactions but also involved in host defence, tissue remodeling, angiogenesis, and fibrogenesis. Here, we show that human intestinal fibroblasts (FB) suppress apoptosis in human intestinal MC dependent on IL-6. Intestinal FB produced IL-6 upon direct stimulation by intestinal MC in co-culture or by MC mediators such as TNF-?, IL-1?, tryptase or histamine. MC incubated with IL-6 survived for up to 3 weeks similar to MC co-cultured with FB and MC survival could be blocked by neutralizing anti-IL-6 Abs. Moreover, FB stimulated by MC mediators upregulated their expression of matrix metalloproteinase-1 (MMP-1), a key fibrolytic enzyme. Noteworthy, FB co-cultured with MC or treated with MMP-1 lost confluence and showed increased numbers of apoptotic cells. Our data indicate an intimate cross talk between mucosal MC and FB resulting in MC survival and induction of a fibrolytic rather than a profibrotic state in FB. PMID:22356938

Montier, Yves; Lorentz, Axel; Krämer, Sigrid; Sellge, Gernot; Schock, Martin; Bauer, Michael; Schuppan, Detlef; Bischoff, Stephan C

2012-09-01

47

An iterative workflow for mining the human intestinal metaproteome  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Peptide spectrum matching (PSM) is the standard method in shotgun proteomics data analysis. It relies on the availability of an accurate and complete sample proteome that is used to make interpretation of the spectra feasible. Although this procedure has proven to be effective in many proteomics studies, the approach has limitations when applied on complex samples of microbial communities, such as those found in the human intestinal tract. Metagenome studi...

Rooijers Koos; Kolmeder Carolin; Juste Catherine; Doré Joël; de Been Mark; Boeren Sjef; Galan Pilar; Beauvallet Christian; de Vos Willem M; Schaap Peter J

2011-01-01

48

Attachment of Cryptosporidium parvum Sporozoites to Human Intestinal Epithelial Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An enzyme-linked immunosorbent assay-based attachment model using the human intestinal cell line Caco-2A was developed to study attachment of Cryptosporidium parvum sporozoites in vitro and to assess potential inhibitors of sporozoite binding. In this system, attachment was related to sporozoite dose, incubation time, and host cell differentiation status. Polyclonal antibodies to C. parvum as well as glycoprotein inhibitors of a sporozoite lectin reduced attachment. This model will be a valua...

Joe, Angela; Verdon, Renaud; Tzipori, Saul; Keusch, Gerald T.; Ward, Honorine D.

1998-01-01

49

Long-term monitoring of the human intestinal microbiota composition  

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The microbiota that colonizes the human intestinal tract is complex and its structure is specific for each of us. In this study we expand the knowledge about the stability of the subject-specific microbiota and show that this ecosystem is stable in short-term intervals (?10 years). The faecal microbiota composition of five unrelated and healthy subjects was analysed using a comprehensive and highly reproducible phylogenetic microarray, the ...

Rajilic-stojanovic, M.; Heilig, G. H. J.; Tims, S.; Zoetendal, E. G.; Vos, W. M.

2013-01-01

50

Ultrastructural localisation of alkaline phosphatase in adult human large intestine.  

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The localisation of alkaline phosphatase in human large intestine was investigated at the ultrastructural level. Alkaline phosphatase was found in the mature absorptive cells of the surface, upper, and middle crypt epithelium; the reaction product was localised in the glycocalyx coat of the microvilli, the Golgi apparatus, and the rough endoplasmic reticulum. Slight activity was found in the immature absorptive cells of the middle and lower regions of the crypts. The undifferentiated cells an...

1982-01-01

51

Isolation and longterm culture of human intestinal microvascular endothelial cells.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Microvascular endothelial cells play an important part in inflammation as well as in organ specific leucocyte traffic, and may be functionally different from large vessel endothelium in this respect. This study therefore established a method for isolation and longterm culture of human intestinal microvascular endothelial cells (HIMEC). After dissociation by collagenase/dispase/DNase of mucosal and submucosal tissue obtained from normal adult jejunum, cells were plated and cultured to subconfl...

Haraldsen, G.; Rugtveit, J.; Kvale, D.; Scholz, T.; Muller, W. A.; Hovig, T.; Brandtzaeg, P.

1995-01-01

52

Radionuclide esophageal and intestinal transit scintigraphy in patients undergoing radiation therapy  

International Nuclear Information System (INIS)

Radiation esophagitis and enteritis are common and significant side effects of radiation therapy. Non-invasive assessment of functional and/or anatomic changes responsible for the symptoms produced by radiation esophagitis and enteritis has been unsatisfactory. This paper demonstrates the value of radionuclide esophageal and intestinal transit scintigraphy in patients undergoing mediastinal or abdominal radiation. (author)

1985-01-01

53

Small intestinal transit in patients with liver cirrhosis and portal hypertension : a descriptive study  

DEFF Research Database (Denmark)

Gastrointestinal dysmotility may be involved in the development of bacterial translocation and infection in patients with liver cirrhosis. The aim of the present study was to describe gastric, small intestinal and colorectal motility and transit in patients with liver cirrhosis and portal hypertension using a magnet-based Motility Tracking System (MTS-1) and standard radiopaque markers.

Karlsen, Stine; Fynne, Lotte

2012-01-01

54

Transcytosis of pancreatic bile salt-dependent lipase through human Int407 intestinal cells.  

Science.gov (United States)

In previous studies, we have shown that the bile-salt-dependent-lipase (BSDL), secreted by pancreatic acinar cells and secreted into the duodenal lumen, can be transcytosed through intestinal cells up to the lamina propria. In this study, we used an in vitro system to provide insights into the apical to basolateral transport of BSDL, across the intestinal barrier. The Int407 human epithelial cell line, grown under conditions that optimize polarity, was used as a tight epithelium model. We attempted to delineate uptake mechanisms and the transcytotic pathway followed by this pancreatic enzyme within the intestinal Int407 cells, which do not produce BSDL. When added to the apical reservoir of Transwell-grown Int407 cells, BSDL was shown to first interact with the apical membrane. Further, BSDL forms clusters that are internalized via clathrin-coated pits. Following endocytosis, BSDL is directed to a nocodazole- and colchicin-sensitive multivesicular compartment. Interestingly, this protein transits through the Golgi apparatus, where it was found to colocalize with the KDEL retrieval-receptor. Finally, enzymatically active intact BSDL was released at the basolateral membrane level. This is the first demonstration for an apical-to-basolateral transcytotic pathway of a secreted pancreatic digestive enzyme through polarized intestinal cells. PMID:11697886

Bruneau, N; Nganga, A; Bendayan, M; Lombardo, D

2001-11-15

55

Ras gene activation in human small intestinal tumors.  

Science.gov (United States)

Expression of the ras oncoprotein in thirteen human small intestinal tumors was investigated employing an immunohistochemical technique. The level of ras p21 was analysed using the monoclonal antibody Y13-259 and the biotin-streptavidin-peroxidace-DAB technique. Nine out of thirteen tumors including one hyperplastic - metaplastic polyp, one adenomatous and papillary polyp of the duodenum, one adenomatous polyp, one leiomyoma, one carcinoid, one lymphoma, one angiosarcoma of the jejunum, one leiomyosarcoma and one metastatic adenocarcinoma of the colon, were found to ''press the ras p21 oncoprotein at elevated levels, as compared to adjacent normal tissue. Whereas in one Brunner's gland adenoma of the duodenum, one neurilemoma, one adenocarcinoma of the small intestine and one metastatic adenocarcinoma of the colon expression of ras p21 was not elevated. The detection of H-ras mutations in codon 12 and K-ras mutations in codons 12 and 13 was also examined using the polymerase chain reaction technique. Four out of the thirteen small intestinal tumors examined possessed mutations of the H-ras gene in codon 12. These included the following, tumors: one Brunner's gland adenoma of the duodenum, one lymphoma, one leiomyo-sarcoma and one metastatic adenocarcinoma of the colon. This is the first demonstration of ras mutations in small intestinal tumors. None of the tumors had mutations in K-ras codons 12 or 13 (Gly-->Asp) It is suggested that the ras p21 oncoprotein may be involved in the pathogenesis and H-ras mutations and be a molecular genetic marker in small intestinal tumors. PMID:21573584

Spandidos, D; Liloglou, T; Arvanitis, D; Gourtsoyiannis, N

1993-04-01

56

Rates of intestinal absorption of molybdenum in humans  

International Nuclear Information System (INIS)

The intestinal absorption of molybdenum in healthy human volunteers has been measured by simultaneous oral and intravenous administration of the stable isotopes 95Mo and 96Mo, and the results were analysed using the convolution integral technique. The results showed that molybdenum ingested in liquid form was rapidly and totally absorbed into the circulation under ordinary intake regimes. The rates and extent of absorption were lower for composite meals, and also for increasing levels of administration. This information can be helpful in the application of the new ICRP model of the human alimentary tract

2006-06-01

57

Rates of intestinal absorption of molybdenum in humans  

Energy Technology Data Exchange (ETDEWEB)

The intestinal absorption of molybdenum in healthy human volunteers has been measured by simultaneous oral and intravenous administration of the stable isotopes {sup 95}Mo and {sup 96}Mo, and the results were analysed using the convolution integral technique. The results showed that molybdenum ingested in liquid form was rapidly and totally absorbed into the circulation under ordinary intake regimes. The rates and extent of absorption were lower for composite meals, and also for increasing levels of administration. This information can be helpful in the application of the new ICRP model of the human alimentary tract.

Giussani, Augusto [Dipartimento di Fisica, Universita degli Studi di Milano, and INFN, Sezione di Milano, via Celoria 16, 20133 Milan (Italy)]. E-mail: augusto.giussani@gsf.de; Arogunjo, Adeseye M. [Department of Physics, Federal University of Technology, P.M.B. 704, Akure, Ondo State (Nigeria); Claire Cantone, Marie [Dipartimento di Fisica, Universita degli Studi di Milano, and INFN, Sezione di Milano, via Celoria 16, 20133 Milan (Italy); Tavola, Federico [Dipartimento di Fisica, Universita degli Studi di Milano, and INFN, Sezione di Milano, via Celoria 16, 20133 Milan (Italy); Veronese, Ivan [Dipartimento di Fisica, Universita degli Studi di Milano, and INFN, Sezione di Milano, via Celoria 16, 20133 Milan (Italy)

2006-06-15

58

An iterative workflow for mining the human intestinal metaproteome  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Peptide spectrum matching (PSM is the standard method in shotgun proteomics data analysis. It relies on the availability of an accurate and complete sample proteome that is used to make interpretation of the spectra feasible. Although this procedure has proven to be effective in many proteomics studies, the approach has limitations when applied on complex samples of microbial communities, such as those found in the human intestinal tract. Metagenome studies have indicated that the human intestinal microbiome contains over 100 times more genes than the human genome and it has been estimated that this ecosystem contains over 5000 bacterial species. The genomes of the vast majority of these species have not yet been sequenced and hence their proteomes remain unknown. To enable data analysis of shotgun proteomics data using PSM, and circumvent the lack of a defined matched metaproteome, an iterative workflow was developed that is based on a synthetic metaproteome and the developing metagenomic databases that are both representative for but not necessarily originating from the sample of interest. Results Two human fecal samples for which metagenomic data had been collected, were analyzed for their metaproteome using liquid chromatography-mass spectrometry and used to benchmark the developed iterative workflow to other methods. The results show that the developed method is able to detect over 3,000 peptides per fecal sample from the spectral data by circumventing the lack of a defined proteome without naive translation of matched metagenomes and cross-species peptide identification. Conclusions The developed iterative workflow achieved an approximate two-fold increase in the amount of identified spectra at a false discovery rate of 1% and can be applied in metaproteomic studies of the human intestinal tract or other complex ecosystems.

Beauvallet Christian

2011-01-01

59

Impaired transit of chyme in chronic intestinal pseudoobstruction. Correction by cisapride  

International Nuclear Information System (INIS)

Chronic intestinal pseudoobstruction is a clinical syndrome whose pathophysiology, objective diagnosis, and treatment are poorly understood. We investigated 8 patients with this syndrome in whom intestinal dysmotility was established manometrically by two or more of the following criteria: abnormal configuration or propagation of interdigestive motor complexes, sustained incoordinate pressure activity, non-propagated bursts of phasic pressure activity, and failure of a solid-liquid meal to induce a fed pattern. To establish the functional impairment and region of the gut primarily affected by the disease, we quantified radio-scintigraphically the gastrointestinal transit of the solid (131I-fiber) and liquid (99 mTc-DTPA) components of a meal. Our techniques allowed us to quantify separately gastric emptying and pylorus-to-cecum transit. Furthermore, we evaluated the effects of a new prokinetic agent, cisapride. Gastric emptying times in pseudoobstruction were not significantly delayed; however, transit times through the small bowel (t1/2) were markedly prolonged [solids, 235 +/- 43 min (mean +/- SEM) vs. 138 +/- 25 controls, p less than 0.05; liquids, 310 +/- 67 vs. 181 +/- 28 controls, p = 0.07]. Cisapride was effective in reducing the delayed intestinal transit time to within the normal range (delta solids = -115 +/- 25 min; delta liquids = -146 +/- 71 min; p less than 0.05 for both). These studies suggest that intestinal dysmotility in this group of patients with pseudoobstruction was associated with delayed small bowel transit of radiolabeled solid and liquid components of chyme. Cisapride can restore to normal the delayed transit, indicating that it may potentially correct the impaired propulsive activity in the small bowel of these patients

1986-01-01

60

[Changes in intestinal transit time induced by bromopride in functional diseases of the colon].  

Science.gov (United States)

Intestinal transit time was studied in two groups of 8 patients with irritable colon. In the first group, the time was longer than normal, whereas in the second it was accelerated. Three subjects in each group received a placebo, while the other five received 60 mg/day bromopride for 15 days. No change in transit time was noted in the controls. Two subjects in Group I displayed a significant reduction in transit time after bromopride, while deceleration and normalisation were observed in 4/5 patients in Group II. PMID:7031516

Alvisi, V; Pavani, F; Loponte, A; Ruina, M; Tralli, M; Tosi, S P; Bagni, B

1981-12-01

 
 
 
 
61

Human milk hyaluronan enhances innate defense of the intestinal epithelium.  

Science.gov (United States)

Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human ?-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human ?-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine H? D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn. PMID:23950179

Hill, David R; Rho, Hyunjin K; Kessler, Sean P; Amin, Ripal; Homer, Craig R; McDonald, Christine; Cowman, Mary K; de la Motte, Carol A

2013-10-01

62

Transport of thiamine in human intestine: mechanism and regulation in intestinal epithelial cell model Caco-2.  

Science.gov (United States)

The present study examined the intestinal uptake of thiamine (vitamin B(1)) using the human-derived intestinal epithelial cells Caco-2 as an in vitro model system. Thiamine uptake was found to be 1) temperature and energy dependent and occurred with minimal metabolic alteration; 2) pH sensitive; 3) Na(+) independent; 4) saturable as a function of concentration with an apparent Michaelis-Menten constant of 3.18 +/- 0.56 microM and maximal velocity of 13.37 +/- 0.94 pmol. mg protein(-1). 3 min(-1); 5) inhibited by the thiamine structural analogs amprolium and oxythiamine, but not by unrelated organic cations tetraethylammonium, N-methylnicotinamide, and choline; and 6) inhibited in a competitive manner by amiloride with an inhibition constant of 0.2 mM. The role of specific protein kinase-mediated pathways in the regulation of thiamine uptake by Caco-2 cells was also examined using specific modulators of these pathways. The results showed possible involvement of a Ca(2+)/calmodulin (CaM)-mediated pathway in the regulation of thiamine uptake. No role for protein kinase C- and protein tyrosine kinase-mediated pathways in the regulation of thiamine uptake was evident. These results demonstrate the involvement of a carrier-mediated system for thiamine uptake by Caco-2 intestinal epithelial cells. This system is Na(+) independent and is different from the transport systems of organic cations. Furthermore, a CaM-mediated pathway appears to play a role in regulating thiamine uptake in these cells. PMID:10516094

Said, H M; Ortiz, A; Kumar, C K; Chatterjee, N; Dudeja, P K; Rubin, S

1999-10-01

63

Small intestinal transit in patients with liver cirrhosis and portal hypertension: a descriptive study  

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Abstract Background Gastrointestinal dysmotility may be involved in the development of bacterial translocation and infection in patients with liver cirrhosis. The aim of the present study was to describe gastric, small intestinal and colorectal motility and transit in patients with liver cirrhosis and portal hypertension using a magnet-based Motility Tracking System (MTS-1) and standard radiopaque markers. Methods We included 15 patients with liver cirrhosis (8 ...

Karlsen Stine; Fynne Lotte; Grønbæk Henning; Krogh Klaus

2012-01-01

64

Probiotic supplementation decreases intestinal transit time: Meta-analysis of randomized controlled trials  

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AIM: To determine the efficacy of probiotic supplementation on intestinal transit time (ITT) and to identify factors that influence these outcomes. METHODS: A systematic review of randomized controlled trials (RCTs) of probiotic supplementation that measured ITT in adults was conducted by searching MEDLINE and EMBASE using relevant key word combinations. Main search limits included RCTs of probiotic supplementation in healthy or constipated adults that measured ITT. Study quality was assessed...

Miller, Larry E.; Ouwehand, Arthur C.

2013-01-01

65

[Human intestinal parasitosis: role of Dientamoeba fragilis in human infections].  

Science.gov (United States)

The Authors report prevalences of intestinal parasitosis among home children and adults during 2002-2004, as in O&P as in acute or prolonged diarrhoea, with particular attention to the role of Dientamoeba fragilis, because often undervalued. Among 3139 subjects, 116 cases of dientamoebiasis (3.7%) and 62 of giardiasis (2.0%) were observed; not typical pathogenic protozoa were reported in 71 cases (2.3%); helminths were identified only in 8 cases (0.5%). Particularly, inside O&P group D. fragilis prevailed in 5.2% of cases (7.8% in adults and 0.5% in children) and G. duodenalis in 2.7% (3.5% and 1.3% respectively); inside acute diarrhoeas D. fragilis prevailed in 1.6% (3.9% and 0.3%) and G. duodenalis in 0.6% (1.3% and 0. 1%); inside prolonged diarrhoeas D. fragilis prevailed in 3.5 % (2.6% and 5.4%) and G. duodenalis in 3.9% (5.8% in adults and never in children). D. fragilis was more often observed among adults (6.3% of all) than among children (0.6%), like G. duodenalis (3.1% versus 0.6%). So, 107 strains of D. fragilis (92.2%) and 53 strains of G. duodenalis (85.5%) were identified in adults. D. fragilis was more frequent among females (24/39 cases, 61.5%, in the last year) while G. duodenalis was more frequent in males (13/23 cases, 56.5%). The Authors conclude underlining the importance of a permanent stain, as Giemsa stain, for a good and complete diagnosis of protozoal intestinal infections, particularly for D. fragilis. PMID:17405510

Crotti, D; D'Annibale, M L

2007-01-01

66

Mechanisms underlying modulation of monocarboxylate transporter 1 (MCT1) by somatostatin in human intestinal epithelial cells  

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Somatostatin (SST), an important neuropeptide of the gastrointestinal tract has been shown to stimulate sodium chloride absorption and inhibit chloride secretion in the intestine. However, the effects of SST on luminal butyrate absorption in the human intestine have not been investigated. Earlier studies from our group and others have shown that monocarboxylate transporter (MCT1) plays an important role in the transport of butyrate in the human intestine. The present studies were undertaken t...

2009-01-01

67

Inhibition of gastric emptying and intestinal transit in anesthetized rats by a Tityus serrulatus scorpion toxin  

Directory of Open Access Journals (Sweden)

Full Text Available The effects of a fraction (T1 of Tityus serrulatus scorpion venom prepared by gel filtration on gastric emptying and small intestinal transit were investigated in male Wistar rats. Fasted animals were anesthetized with urethane, submitted to tracheal intubation and right jugular vein cannulation. Scorpion toxin (250 µg/kg or saline was injected iv and 1 h later a bolus of saline (1.0 ml/100 g labeled with 99m technetium-phytate (10 MBq was administered by gavage. After 15 min, animals were sacrificed and the radioactivity remaining in the stomach was determined. Intestinal transit was evaluated by instillation of a technetium-labeled saline bolus (1.0 ml through a cannula previously implanted in the duodenum. After 60 min, the progression of the marker throughout 7 consecutive gut segments was estimated by the geometric center method. Gastric retention of the liquid test meal in rats injected with scorpion toxin (median: 88%; range: 52-95% was significantly higher (P<0.02 than in controls (54%; 21-76%, an effect which was not modified by gastric secretion blockade with ranitidine. The progression of the isotope marker throughout the small intestine was significantly slower (P<0.05 in rats treated with toxin (1.2; 1.0-2.5 than in control animals (2.3; 1.0-3.2. Inhibition of both gastric emptying and intestinal transit in rats injected with scorpion toxin suggests an increased resistance to aboral flow, which might be caused by abnormal neurotransmitter release or by the local effects of venom on smooth muscle cells.

L.E.A. Troncon

2000-09-01

68

Screening of Exopolysaccharide-Producing Lactobacillus and Bifidobacterium Strains Isolated from the Human Intestinal Microbiota?  

Science.gov (United States)

Using phenotypic approaches, we have detected that 17% of human intestinal Lactobacillus and Bifidobacterium strains could be exopolysaccharide (EPS) producers. However, PCR techniques showed that only 7% harbored genes related to the synthesis of heteropolysaccharides. This is the first work to screen the human intestinal ecosystem for the detection of EPS-producing strains.

Ruas-Madiedo, Patricia; Moreno, Jose Antonio; Salazar, Nuria; Delgado, Susana; Mayo, Baltasar; Margolles, Abelardo; de los Reyes-Gavilan, Clara G.

2007-01-01

69

Screening of exopolysaccharide-producing Lactobacillus and Bifidobacterium strains isolated from the human intestinal microbiota.  

Science.gov (United States)

Using phenotypic approaches, we have detected that 17% of human intestinal Lactobacillus and Bifidobacterium strains could be exopolysaccharide (EPS) producers. However, PCR techniques showed that only 7% harbored genes related to the synthesis of heteropolysaccharides. This is the first work to screen the human intestinal ecosystem for the detection of EPS-producing strains. PMID:17483284

Ruas-Madiedo, Patricia; Moreno, José Antonio; Salazar, Nuria; Delgado, Susana; Mayo, Baltasar; Margolles, Abelardo; de Los Reyes-Gavilán, Clara G

2007-07-01

70

Human intestinal ischemia-reperfusion-induced inflammation characterized: experiences from a new translational model.  

Science.gov (United States)

Human intestinal ischemia-reperfusion (IR) is a frequent phenomenon carrying high morbidity and mortality. Although intestinal IR-induced inflammation has been studied extensively in animal models, human intestinal IR induced inflammatory responses remain to be characterized. Using a newly developed human intestinal IR model, we show that human small intestinal ischemia results in massive leakage of intracellular components from ischemically damaged cells, as indicated by increased arteriovenous concentration differences of intestinal fatty acid binding protein and soluble cytokeratin 18. IR-induced intestinal barrier integrity loss resulted in free exposure of the gut basal membrane (collagen IV staining) to intraluminal contents, which was accompanied by increased arteriovenous concentration differences of endotoxin. Western blot for complement activation product C3c and immunohistochemistry for activated C3 revealed complement activation after IR. In addition, intestinal IR resulted in enhanced tissue mRNA expression of IL-6, IL-8, and TNF-alpha, which was accompanied by IL-6 and IL-8 release into the circulation. Expression of intercellular adhesion molecule-1 was markedly increased during reperfusion, facilitating influx of neutrophils into IR-damaged villus tips. In conclusion, this study for the first time shows the sequelae of human intestinal IR-induced inflammation, which is characterized by complement activation, production and release of cytokines into the circulation, endothelial activation, and neutrophil influx into IR-damaged tissue. PMID:20348235

Grootjans, Joep; Lenaerts, Kaatje; Derikx, Joep P M; Matthijsen, Robert A; de Bruïne, Adriaan P; van Bijnen, Annemarie A; van Dam, Ronald M; Dejong, Cornelis H C; Buurman, Wim A

2010-05-01

71

Evaluation of intestinal transit time of root and leaves of Ipomea sepiaria.  

Science.gov (United States)

Ipomoea sepiaria Koenig Ex. Roxb is considered to be one of the source plants of the classical herb Lakshmana. In folklore, the herb is well known for its laxative activity. This plant belongs to Convolvulaceae family. It is observed that the plants of this family especially the species of Ipomoea are rich in purgative resins. The present experimental study was carried out to evaluate the effect of leaf and root of I. sepiaria on intestinal transit time on Swiss albino mice and the test drugs were administered in dose of 400 mg/kg. Evaluation of intestinal transit time was carried out by adopting Kaolin expulsion test and latency of onset of kaolin expulsion in fecal matter. The results shows that both root and leaf samples of I. sepiaria have marked intestinal motility enhancing property, among which leaf sample is found to be better. Hence, for the therapeutic purpose leaf can be preferred to get better activity profile and also to prevent destructive harvesting of the plant. PMID:24696582

Majumder, Sayani; Ashok, B K; Nishteswar, K

2013-10-01

72

Small intestinal transit in patients with liver cirrhosis and portal hypertension: a descriptive study  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Gastrointestinal dysmotility may be involved in the development of bacterial translocation and infection in patients with liver cirrhosis. The aim of the present study was to describe gastric, small intestinal and colorectal motility and transit in patients with liver cirrhosis and portal hypertension using a magnet-based Motility Tracking System (MTS-1 and standard radiopaque markers. Methods We included 15 patients with liver cirrhosis (8 Child-Pugh A, 6 Child-Pugh B, and 1 Child-Pugh C and portal hypertension (11 males, median age 54?years (range 38–73, median hepatic venous pressure gradient 18?mmHg (range 12–37, and 18 healthy controls (8 males, median age 58?years (range 34–64. The gastric emptying time and small intestinal motility were evaluated by MTS-1, and the total gastrointestinal transit time was assessed by radiopaque markers and abdominal radiographs. Results The velocity through the proximal small intestine was significantly higher in cirrhotic patients (median 1.27 metres (m/hour, range 0.82–2.68 than in the healthy controls (median 1.00?m/hour, range 0.46–1.88 (p?=?0.03. Likewise, the magnet travelled significantly longer in both fast (p?=?0.04 and slow movements (p?=?0.05 in the patient group. There was no significant difference in either gastric emptying time—23?minutes (range 5–131 in patients and 29?minutes (range 10.5–182 in healthy controls (p?=?0.43—or total gastrointestinal transit time—1.6?days (range 0.5–2.9 in patients and 2.0?days (range 1.0–3.9 in healthy controls (p?=?0.33. No correlation was observed between the hepatic venous pressure gradient and the velocity of the magnet through the small intestine. Conclusion Patients with liver cirrhosis and portal hypertension demonstrated faster-than-normal transit through the proximal small intestine. This may be due to an overactive bowel, as suggested by previous studies.

Karlsen Stine

2012-12-01

73

Effect of pregnancy on intestinal transit: comparison of results using radioactive and non-radioactive test meals  

International Nuclear Information System (INIS)

Studies were performed to determine the effect of pregnancy on both gastrointestinal transit and small intestinal transit. Gastrointestinal transit was examined by determining the leading edge of distribution within the small intestine of a charcoal marker placed directly into the stomach. Intestinal transit was evaluated by quantifying the distribution of a radiolabelled marker placed dirrectly into the duodenum. The distribution of the marker was determined (1) by calculating the slope of the distribution curve and (2) by calculating the geometric center of distribution of the radioisotope. In all studies the data from animals in either the second or third trimester of pregnancy were compared with the results obtained from non-pregnant females. The results confirm previous observations that gastrointestinal transit is reduced during the latter stages of pregnancy. This can be explained, at least in part, by a decreased intestinal transit. The data also suggest that analysis of the geometric center of distribution provides a more sensitive and reliable measure of intestinal transit than does analysis of the slope of the distribution curve

1982-12-06

74

Host-bacterial mutualism in the human intestine.  

Science.gov (United States)

The distal human intestine represents an anaerobic bioreactor programmed with an enormous population of bacteria, dominated by relatively few divisions that are highly diverse at the strain/subspecies level. This microbiota and its collective genomes (microbiome) provide us with genetic and metabolic attributes we have not been required to evolve on our own, including the ability to harvest otherwise inaccessible nutrients. New studies are revealing how the gut microbiota has coevolved with us and how it manipulates and complements our biology in ways that are mutually beneficial. We are also starting to understand how certain keystone members of the microbiota operate to maintain the stability and functional adaptability of this microbial organ. PMID:15790844

Bäckhed, Fredrik; Ley, Ruth E; Sonnenburg, Justin L; Peterson, Daniel A; Gordon, Jeffrey I

2005-03-25

75

Effects of casoxin 4 on morphine inhibition of small animal intestinal contractility and gut transit in the mouse  

Directory of Open Access Journals (Sweden)

Full Text Available Glen S Patten1,2, Richard J Head1, Mahinda Y Abeywardena1,21CSIRO Preventative Health National Research Flagship, Adelaide, Australia; 2CSIRO Food and Nutritional Sciences, Adelaide, AustraliaBackground and aims: Chronic opioid analgesia has the debilitating side-effect of constipation in human patients. The major aims of this study were to: 1 characterize the opioid-specific antagonism of morphine-induced inhibition of electrically driven contraction of the small intestine of mice, rats, and guinea pigs; and 2 test if the oral delivery of small milk-derived opioid antagonist peptides could block morphine-induced inhibition of intestinal transit in mice.Methods: Mouse, rat, and guinea pig intact ileal sections were electrically stimulated to contract and inhibited with morphine in vitro. Morphine inhibition was then blocked by opioid subtype antagonists in the mouse and guinea pig. Using a polymeric dye, Poly R-478, the opioid antagonists casoxin 4 and lactoferroxin A were tested orally for blocking activity of morphine inhibition of gut transit in vivo by single or double gavage techniques.Results: The guinea pig tissue was more sensitive to morphine inhibition compared with the mouse or the rat (IC50 [half maximal inhibitory concentration] values as nmol/L ± SEM were 34 ± 3, 230 ± 13, and 310 ± 14 respectively (P < 0.01. The inhibitory influence of opioid agonists (IC50 in electrically driven ileal mouse preparations were DADLE ([D-Ala2, D-Leu5]-enkephalin ? met-enkephalin ? dynorphin A ? DAMGO ([D-Ala2, N-Me-Phe4, Gly-ol5]-enkephalin > morphine > morphiceptin as nmol/L 13.9, 17.3, 19.5, 23.3, 230, and 403 respectively. The mouse demonstrated predominantly ?- and ?-opioid receptor activity with a smaller µ-opioid receptor component. Both mouse and guinea pig tissue were sensitive to casoxin 4 antagonism of morphine inhibition of contraction. In contrast to naloxone, relatively high oral doses of the µ-opioid receptor antagonists, casoxin 4 and lactoferroxin A, applied before and after morphine injection were unable to antagonize morphine inhibition of gut transit.Conclusions: Casoxin 4 reverses morphine-induced inhibition of contraction in mice and guinea pigs in vitro but fails to influence morphine inhibition of mouse small intestinal transit by the oral route.Keywords: lactoferroxin A, µ-opioid receptor antagonist, opioid agonists

Glen S Patten

2011-02-01

76

T cell receptor V beta expression in human intestine: regional variation in postnatal intestine and biased usage in fetal gut.  

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A panel of T cell receptor V beta specific monoclonal antibodies was used to analyse V beta gene usage at different sites in human postnatal and fetal intestine. In normal small intestine, at a single site, different patients showed expansion of T cells expressing individual V beta s. Lamina propria and epithelial T cells from the same patient showed overlapping but not identical V beta dominance. V beta dominance was also shown in the T cells of the colonic lamina propria. Analysis of two se...

Thomas, R.; Schu?rmann, G.; Lionetti, P.; Pender, S. L.; Macdonald, T. T.

1996-01-01

77

Microbial Eco-Physiology of the human intestinal tract: a flow cytometric approach  

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This thesis describes a multifaceted approach to further enhance our view of the complex human intestinal microbial ecosystem. This approach combines me advantages of flow cyrometry (FCM), a single cell and high-throughput technology, and molecular techniques that have proven themselves to be invaluabIe tools in studying the microbial diversity and structure of the intestinal microbiota. The ultimate aim was to relate the genetic biodiversity of the intestinal microbiota with their in situ ph...

Ben Amor, K.

2004-01-01

78

Practical techniques for detection of Toll-like Receptor-4 (TLR4) in the human Intestine  

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The human intestine has evolved in the presence of a diverse array of luminal microorganisms. In order to maintain intestinal homeostasis, mucosal immune responses to these microorganisms must be tightly regulated. The intestine needs to be able to respond to pathogenic organisms while at the same time maintain tolerance to normal commensal flora. Toll-like receptors (TLRs) play an important role in this delicate balance. TLRs are transmembrane non-catalytic receptor proteins that induce acti...

Ungaro, Ryan; Abreu, Maria T.; Fukata, Masayuki

2009-01-01

79

Zingerone regulates intestinal transit, attenuates behavioral and oxidative perturbations in irritable bowel disorder in rats.  

Science.gov (United States)

Stress can lead to the manifestation of functional gastrointestinal disorders, the most prominent being irritable bowel disorder. The present study investigated the impact zingerone in ameliorating chronic water stress induced irritable bowel disorder, brain gut axis dysfunction and dysregulation of the intestinal barrier due to oxidative stress. Rats were randomly allocated to groups and subjected to chronic water stress for a period of 21 days for 1h and the fecal pellet output was measured. At the end of chronic stress, behavioral assessment for anxiety like behavior was recorded and plasma corticosterone levels were measured 60min after water stress. The colonic transit was determined, levels of oxidative and antioxidant biomarkers were measured in the colon homogenate. Myeloperoxidase activity was determined as an indirect index of neutrophil infiltration. Chronic water stress increased the rate of colonic transit, fecal output, induced behavioral changes, and decreased antioxidant levels. An increase in lipid peroxide levels, catalase and corticosterone was observed. Mast cell infiltration was evident in the stressed group. Zingerone significantly reduced colonic transit, fecal output, neutrophil infiltration, and lipid peroxide formation. The levels of catalase were not altered; however, a marginal increase in the levels of glutathione peroxidase was observed. Zingerone significantly enhanced the levels of superoxide dismutase, glutathione and decreased the levels of corticosterone. Zingerone produced marked improvement in stress induced irritable bowel disorder which could be attributed to the powerful antioxidant nature, direct effect on the intestinal smooth muscle and adaptogenic nature. PMID:24262066

Banji, David; Banji, Otilia J F; Pavani, Bandlapalli; Kranthi Kumar, Ch; Annamalai, A R

2014-03-15

80

Intestinal transit time in the population calculated from self made observations of defecation.  

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STUDY OBJECTIVES--To assess the feasibility of estimating intestinal transit time in the general population using self recorded data on stool form, frequency of defecation, and the interdefecatory time interval. DESIGN--Prospective measurement of bowel function. SETTING--Bristol, Avon, UK between 1987 and 1989. SUBJECTS--Subjects were drawn from 1897 people who comprised 72.2% of a stratified random sample of all men aged 40-69 years and women aged 25-69 years on the lists of 19 general medic...

Probert, C. J.; Emmett, P. M.; Heaton, K. W.

1993-01-01

 
 
 
 
81

Distribution of the IgG Fc Receptor, FcRn, in the Human Fetal Intestine  

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The intestinal Fc receptor, FcRn, functions in the maternofetal transfer of gamma globulin (IgG) in the neonatal rodent. In humans, most of this transfer is presumed to occur in utero via the placenta. Although the fetus swallows amniotic fluid that contains immunoglobulin, it is unknown whether this transfer also occurs via the fetal intestine. A human FcRn has been identified in the syncytiotrophoblast that mediates the maternofetal transfer of antibody. It has also been identified in human...

Shah, Uzma; Dickinson, Bonny L.; Blumberg, Richard S.; Simister, Neil E.; Lencer, Wayne I.; Walker, W. Allan

2003-01-01

82

Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to sugar beet fibre and decreasing intestinal transit time pursuant to Article 13(5) of Regulation (EC) No 1924/2006  

DEFF Research Database (Denmark)

Following an application from Nordic Sugar A/S, submitted pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Denmark, the Panel on Dietetic Products, Nutrition and Allergies was asked to deliver an opinion on the scientific substantiation of a health claim based on newly developed scientific evidence related to sugar beet fibre and â??decreasing intestinal transit timeâ?. The food constituent that is the subject of the health claim is sugar beet fibre. This opinion applies to sugar beet fibre naturally present in foods and to those forms added to foods. The Panel considers that sugar beet fibre is sufficiently characterised in relation to the claimed effect. The claimed effect is â??decreasing intestinal transit timeâ?. The target population proposed by the applicant is people who want to improve or maintain normal bowel function. The Panel considers that decreasing intestinal (orofaecal) transit time may be a beneficial physiological effect. The applicant provided four human studies as pertinent to the health claim. The Panel considers that no conclusion can be drawn from three studies for the scientific substantiation of the claim owing to methodological weaknesses whereas one human intervention study showed no effect of the consumption of sugar beet fibre on decreasing intestinal (orofaecal) transit time. In weighing the evidence the Panel took into account that one human study from which conclusions could be drawn for the scientific substantiation of the claim showed no effect of sugar beet fibre on intestinal (orofaecal) transit time. The Panel concludes that a cause and effect relationship has not been established between the consumption of sugar beet fibre and decreasing intestinal transit time. © European Food Safety Authority, 2011

Tetens, Inge

2011-01-01

83

Intestinal Pseudo-Obstruction as an Unusual Gastrointestinal Presentation in Pediatric Human Immunodeficiency Virus Infection  

Directory of Open Access Journals (Sweden)

Full Text Available Intestinal pseudo-obstruction is a condition in which the intestine’s ability to push food through is reduced. It often leads to the dilation of the various parts of the bowel. It can be idiopathic or inherited from a parent, or caused by another disease. We report a rare case of human immunodeficiency virus (HIV infection in a 3-year-old boy who referred with acute abdominal pain, and was later diagnosed as having intestinal pseudo-obstruction caused by HIV. The underlying causes of intestinal pseudo-obstruction should be taken into account. HIV induced pseudo-obstruction may be considered in the differential diagnosis of pediatric intestinal pseudo-obstruction in order to provide a timely diagnosis and optimal care of children with HIV.

Mozhgan Zahmatkeshan

2014-01-01

84

The scintigraphic determination of small intestinal transit time in patients with irritable bowel syndrome  

International Nuclear Information System (INIS)

Diffuse disturbance in gastrointestinal motility may be present in patients with irritable bowel syndrome (IBS). To further investigate small intestinal motility in IBS patients small intestinal transit time (SITT) was determined and related to the symptom status. 11 female patients with IBS (mean age 29 years) were divided into those whose predominate symptom was diarrhea (N=6), and those with only constipation (N=5). All subjects ingested an isosmotic solution of lactulose (10 gm in 150cc of water) labeled with 99m-Tc-DTPA (Sn). The patient was studied supine under a 25 inch gamma camera with data collected at 1 frame per minute for 180 minutes or until activity appeared in the ascending colon. Regions of interest were selected over the cecum and ascending colon. The time of first appearance of radioactivity in the region of the cecum was taken as the small intestinal transit time. SITT in the 5 normal females was 98.7 +- 13 min (mean +- SEM). SITT in the IBS patients with diarrhea, 67.3 +- 7 min was significantly faster (p< 0.08). SITT in the constipated IBS patients, 126 +- 12 min, was slower than normals and significantly different from diarrhea patients (p< 0.001). These studies show that IBS patients with diarrhea have significantly faster SITT than normals while constipated IBS patients have significantly slower SITT than the diarrhea subgroup. Further, this study emphasizes the need to study the various symptomatic subgroups of IBs patients independently and indicates a possible role for abnormal SITT in the pathogenesis of IBS

1984-06-05

85

Adhesion and absorption of Tc-99 labelled tracers for estimating the intestinal transit  

International Nuclear Information System (INIS)

Liquid, semisolid and solid markers are used to calculate esophageal transit, gastric emptying or intestinal transit. The purpose of this study was to prove in vivo stability and wall absorption. 41 Wistar rats were fed with sup(99m)Tc-DTPA (n=11), sup(99m)Tc-labeled chicken liver (n=11), sup(99m)Tc-Chelex (n=11) or sup(99m)Tc-pertechnetate (n=8). One to three hours later the animals were killed, the gut was dissected and rinsed with water. The water for rinsing, the activity of the intestinal wall and other organs were measured in a whole body counter. The calculated fractions (%) of intraluminal (1), wall-absorbed (W) and extraintestianl (E) activity in relation to total counts were: DPTA: (1) 89 +- 3.2, (W) 8 +- 2.1, (E) 2.3 +- 1.6. CHELEX: (1) 98.8 +- 0.6, (W) 0.9 +-0.4, (E) 0.3 +- 0.4. CHICKEN LIVER: (1) 96.9 +- 1.3, (W) 2.3 +- 1.1, (E) 0.8 +- 0.8. PERTECHNETATE: (1) 36.4 +- 12, (W) 9.5 +- 2.7, (E) 54.2 +- 13. The differences were significant between all groups (p<0.05). The most inert tracer is Chelex which, in contrast to chicken liver, is simple to handle and is different to liquid tracers in intraluminal kinetics. Clinical use is proposed. (Author)

1986-01-01

86

Inhibition of gastric emptying and intestinal transit in anesthetized rats by a Tityus serrulatus scorpion toxin  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The effects of a fraction (T1) of Tityus serrulatus scorpion venom prepared by gel filtration on gastric emptying and small intestinal transit were investigated in male Wistar rats. Fasted animals were anesthetized with urethane, submitted to tracheal intubation and right jugular vein cannulation. S [...] corpion toxin (250 µg/kg) or saline was injected iv and 1 h later a bolus of saline (1.0 ml/100 g) labeled with 99m technetium-phytate (10 MBq) was administered by gavage. After 15 min, animals were sacrificed and the radioactivity remaining in the stomach was determined. Intestinal transit was evaluated by instillation of a technetium-labeled saline bolus (1.0 ml) through a cannula previously implanted in the duodenum. After 60 min, the progression of the marker throughout 7 consecutive gut segments was estimated by the geometric center method. Gastric retention of the liquid test meal in rats injected with scorpion toxin (median: 88%; range: 52-95%) was significantly higher (P

L.E.A., Troncon; A.A., Santos; V.L., Garbacio; M., Secaf; A.V., Verceze; J.R., Cunha-Melo.

87

Linaclotide, through activation of guanylate cyclase C, acts locally in the gastrointestinal tract to elicit enhanced intestinal secretion and transit.  

Science.gov (United States)

Linaclotide is a first-in-class, orally administered 14-amino acid peptide that is in development for the treatment of irritable bowel syndrome with constipation and chronic constipation. We have characterized the solution structure of linaclotide, the in vitro binding and agonist activity to guanylate cyclase C receptors, the stability of linaclotide under conditions mimicking the gastric environment, oral bioavailability, and the pharmacodynamic effects in rat models of gastrointestinal transit and intestinal secretion. Nuclear magnetic resonance spectroscopy analysis determined that the molecular structure of linaclotide is stabilized by three intramolecular disulfide bridges. Linaclotide exhibited high affinity and pH-independent binding (K(i): 1.23-1.64 nM) to guanylate cyclase C receptors on human colon carcinoma T84 cells and concomitantly, linaclotide binding resulted in a significant, concentration-dependent accumulation of intracellular cyclic guanosine-3', 5'-monophosphate (cGMP) (EC??:99 nM). Linaclotide was stable after 3 h incubation in simulated gastric fluid (pH 1) and similarly, was completely resistant to hydrolysis by pepsin. Pharmacokinetic analysis of linaclotide showed very low oral bioavailability (0.1%). Orally administered linaclotide elicited a significant, dose-dependent increase in gastrointestinal transit rates in rats at doses of ?5 ?g/kg. Exposure of surgically ligated small intestinal loops to linaclotide induced a significant increase in fluid secretion, accompanied by a significant increase in intraluminal cGMP levels. These results suggest that the guanylate cyclase C agonist linaclotide elicits potent pharmacological responses locally in the gastrointestinal tract, and that orally administered guanylate cyclase C agonists may be capable of improving bowel habits in patients suffering from irritable bowel syndrome with constipation and chronic constipation. PMID:20863829

Busby, Robert W; Bryant, Alexander P; Bartolini, Wilmin P; Cordero, Etchell A; Hannig, Gerhard; Kessler, Marco M; Mahajan-Miklos, Shalina; Pierce, Christine M; Solinga, Robert M; Sun, Li Jing; Tobin, Jenny V; Kurtz, Caroline B; Currie, Mark G

2010-12-15

88

Effects of Clindamycin on Adherence of Clostridium difficile to Human Embryonic Intestinal Cells.  

Science.gov (United States)

An in vitro assay system, consisting of monolayers of human embryonic intestinal cells (HEI) and Clostridium difficile, was used to observe cell surface and cytoplasmic interactions. Microorganism test conditions include toxin B positive ( 938) and toxin ...

H. P. Dalton S. J. Wood V. Mumaw

1991-01-01

89

Permeability of rhynchophylline across human intestinal cell in vitro  

Science.gov (United States)

Rhynchophylline (Rhy) is the major component of Uncaria species, which is used in Chinese traditional medicine for the treatment of central nervous system disorders. However, its oral bioavailability has not been known. This study aims to investigate the intestinal permeability and related mechanisms of Rhy using cultured human epithelial Caco-2 cells. The cytotoxicity of Rhy on Caco-2 cells was evaluated with MTT assay. The effect of Rhy on the integrity of Caco-2 cell monolayer was assayed with transepithelial electrical resistance. The permeability of Rhy across cell monolayer was assayed by measuring Rhy quantity in received side with HPLC. The effect of Rhy on the expression of P-glycoprotein and MDR1 was detected with Western blot and flow cytometry, respectively. In the concentration of Rhy, which did not produce toxicity on cell viability and integrity of Caco-2 cell monolayer, Rhy crossed the monolayer with velocity 2.76~5.57×10^-6 cm/sec and 10.68~15.66×10^-6 cm/sec from apical to basolateral side and from basolateral to apical side, respectively. The permeability of Rhy was increased by verapamil, a P-glycoprotein inhibitor, or rhodamine123, a P-glycoprotein substrate. Rhy revealed an induction effect on P-glycoprotein expression in Caco-2 cells. These results demonstrate the low permeability of Rhy in intro, and suggest that P-glycoprotein may underlie the mechanism.

Ma, Bo; Wang, Jing; Sun, Jing; Li, Ming; Xu, Huibo; Sun, Guibo; Sun, Xiaobo

2014-01-01

90

Permeability of rhynchophylline across human intestinal cell in vitro.  

Science.gov (United States)

Rhynchophylline (Rhy) is the major component of Uncaria species, which is used in Chinese traditional medicine for the treatment of central nervous system disorders. However, its oral bioavailability has not been known. This study aims to investigate the intestinal permeability and related mechanisms of Rhy using cultured human epithelial Caco-2 cells. The cytotoxicity of Rhy on Caco-2 cells was evaluated with MTT assay. The effect of Rhy on the integrity of Caco-2 cell monolayer was assayed with transepithelial electrical resistance. The permeability of Rhy across cell monolayer was assayed by measuring Rhy quantity in received side with HPLC. The effect of Rhy on the expression of P-glycoprotein and MDR1 was detected with Western blot and flow cytometry, respectively. In the concentration of Rhy, which did not produce toxicity on cell viability and integrity of Caco-2 cell monolayer, Rhy crossed the monolayer with velocity 2.76~5.57×10^-6 cm/sec and 10.68~15.66×10^-6 cm/sec from apical to basolateral side and from basolateral to apical side, respectively. The permeability of Rhy was increased by verapamil, a P-glycoprotein inhibitor, or rhodamine123, a P-glycoprotein substrate. Rhy revealed an induction effect on P-glycoprotein expression in Caco-2 cells. These results demonstrate the low permeability of Rhy in intro, and suggest that P-glycoprotein may underlie the mechanism. PMID:24966905

Ma, Bo; Wang, Jing; Sun, Jing; Li, Ming; Xu, Huibo; Sun, Guibo; Sun, Xiaobo

2014-01-01

91

The mucin degrader Akkermansia muciniphila is an abundant resident of the human intestinal tract  

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A 16S rRNA-targeted probe, MUC-1437, was designed and validated in order to determine the presence and numbers of cells of Akkermansia muciniphila, a mucin degrader, in the human intestinal tract. As determined by fluorescent in situ hybridization, A. muciniphila accounted more than 1% of the total fecal cells and was shown to be a common bacterial component of the human intestinal tract

Derrien, M. M. N.; Collado, M. C.; Ben-amor, K.; Salminen, S.; Vos, W. M.

2008-01-01

92

The Mucin Degrader Akkermansia muciniphila Is an Abundant Resident of the Human Intestinal Tract? †  

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A 16S rRNA-targeted probe, MUC-1437, was designed and validated in order to determine the presence and numbers of cells of Akkermansia muciniphila, a mucin degrader, in the human intestinal tract. As determined by fluorescent in situ hybridization, A. muciniphila accounted more than 1% of the total fecal cells and was shown to be a common bacterial component of the human intestinal tract.

Derrien, Muriel; Collado, M. Carmen; Ben-amor, Kaouther; Salminen, Seppo; Vos, Willem M.

2008-01-01

93

The Mucin degrader Akkermansia muciniphila is an abundant resident of the human intestinal tract.  

Science.gov (United States)

A 16S rRNA-targeted probe, MUC-1437, was designed and validated in order to determine the presence and numbers of cells of Akkermansia muciniphila, a mucin degrader, in the human intestinal tract. As determined by fluorescent in situ hybridization, A. muciniphila accounted more than 1% of the total fecal cells and was shown to be a common bacterial component of the human intestinal tract. PMID:18083887

Derrien, Muriel; Collado, M Carmen; Ben-Amor, Kaouther; Salminen, Seppo; de Vos, Willem M

2008-03-01

94

Exploring the Diversity of the Bifidobacterial Population in the Human Intestinal Tract?  

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Although the health-promoting roles of bifidobacteria are widely accepted, the diversity of bifidobacteria among the human intestinal microbiota is still poorly understood. We performed a census of bifidobacterial populations from human intestinal mucosal and fecal samples by plating them on selective medium, coupled with molecular analysis of selected rRNA gene sequences (16S rRNA gene and internally transcribed spacer [ITS] 16S-23S spacer sequences) of isolated colonies. A total of 900 isol...

Turroni, Francesca; Foroni, Elena; Pizzetti, Paola; Giubellini, Vanessa; Ribbera, Angela; Merusi, Paolo; Cagnasso, Patrizio; Bizzarri, Barbara; Angelis, Gian Luigi; Shanahan, Fergus; Sinderen, Douwe; Ventura, Marco

2009-01-01

95

Morphology of Diagnostic Stages of Intestinal Parasites of Humans.  

Science.gov (United States)

The diagnostic stages of intestinal parasites are differentiated on the basis of specific morphologic features that can be seen microscopically. Although Dientamoeba fragilis is a flagellate, morphologically, it resembles the amebae. Therefore, in this ma...

M. M. Brooke D. M. Melvin

1984-01-01

96

Neuroendocrine and proliferative potential of human intestinal cells during aging.  

Science.gov (United States)

A population of neuroendocrine cells secreting chromogranin A was verified in the intestine of subjects aged over 60 years. The count of intestinal cells expressing chromogranin A and Ki-67 proliferation protein increases with aging. More intensive expression of chromogranin A and Ki-67 protein in senile age and in long-livers is presumably a compensatory mechanism aimed at the gastrointestinal function maintenance during its age-associated involution. PMID:22235431

Trofimov, A V; Sevostianova, N N; Linkova, N S; Kolmakov, A N; Polyakova, V O

2011-04-01

97

Ethics of emerging technologies and their transition to accepted practice: intestinal transplant for short bowel syndrome.  

Science.gov (United States)

Parental counseling becomes complex when considering the use of emerging technologies, especially if it is unclear whether the level of evidence is sufficient to transform the proposed therapy into accepted practice. This paper addresses ethical issues underlying medical decision-making and counseling in the setting of emerging treatments, when long-term outcomes are still in the process of being fully validated. We argue that the ethical transition of emerging technologies, ideally from ethically impermissible to permissible, to obligatory, depends primarily on two factors: outcome data (or prognosis) and treatment feasibility. To illustrate these points, we will use intestinal transplant for short bowel syndrome (SBS) as a specific example. After reviewing the data, this paper will identify the ethical justifications for both comfort care only and intestinal transplant in patients with ultra SBS, and argue that both are ethically permissible, but neither is obligatory. The approach outlined will not only be valuable as ultra SBS outcomes data continue to change, but will also be applicable to other novel therapies as they emerge in perinatal medicine. PMID:23014383

Cummings, C L; Mercurio, M R

2012-10-01

98

Effect of codeine and loperamide on upper intestinal transit and absorption in normal subjects and patients with postvagotomy diarrhoea.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Patients with chronic severe diarrhoea after truncal vagotomy and pyloroplasty are often difficult to treat using conventional antidiarrhoeal drugs and remain severely disabled. We examined the effect of two drugs, codeine phosphate and loperamide, on upper intestinal transit and carbohydrate absorption, measured non-invasively by serial exhaled breath hydrogen monitoring, in patients with postvagotomy diarrhoea who had previously failed to gain relief from drug therapy. Orocaecal transit was...

1988-01-01

99

Human Rights and Transitional Societies: Contemporary Challenges  

DEFF Research Database (Denmark)

This paper will assess how alternative approaches to transitional justice have the potential for overcoming tensions in between human rights standards. A rule in international law prescribing that states have a duty to prosecute gross human rights violations has emerged. Accordingly, transitional societies are said to have an obligation to apply criminal justice in dealing with such past violations. In Rwanda, the transitional government decided to prosecute the perpetrators of the 1994 genocide. As a result of widespread participation in the genocide and a devastated legal sector, difficulties in respecting the rights of the accused arose. A group of paralegals known as the "Corps of Judicial Defenders" was thus relied upon as to provide legal assistance for genocide suspects, but also for civil parties. This paper describes the work of these paralegals relating to the transitional trials, and, more generally, asserts how Judicial Defenders may have contributed to justice in other ways in post conflict Rwanda. The author argues that an efficient transitional justice policy must take sufficiently into account the context of the society in question, and aim at establishing linkages between justice in transitions and justice in the long-term.

Hansen, Thomas Obel

2008-01-01

100

Nucleotide and amino acid sequences of human intestinal alkaline phosphatase: close homology to placental alkaline phosphatase  

International Nuclear Information System (INIS)

A cDNA clone for human adult intestinal alkaline phosphatase (ALP) [orthophosphoric-monoester phosphohydrolase (alkaline optimum); EC 3.1.3.1] was isolated from a ?gt11 expression library. The cDNA insert of this clone is 2513 base pairs in length and contains an open reading frame that encodes a 528-amino acid polypeptide. This deduced polypeptide contains the first 40 amino acids of human intestinal ALP, as determined by direct protein sequencing. Intestinal ALP shows 86.5% amino acid identity to placental (type 1) ALP and 56.6% amino acid identity to liver/bone/kidney ALP. In the 3'-untranslated regions, intestinal and placental ALP cDNAs are 73.5% identical (excluding gaps). The evolution of this multigene enzyme family is discussed

1987-01-01

 
 
 
 
101

Association between the ABO blood group and the human intestinal microbiota composition  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The mucus layer covering the human intestinal epithelium forms a dynamic surface for host-microbial interactions. In addition to the environmental factors affecting the intestinal equilibrium, such as diet, it is well established that the microbiota composition is individually driven, but the host factors determining the composition have remained unresolved. Results In this study, we show that ABO blood group is involved in differences in relative proportion and overall profiles of intestinal microbiota. Specifically, the microbiota from the individuals harbouring the B antigen (secretor B and AB differed from the non-B antigen groups and also showed higher diversity of the Eubacterium rectale-Clostridium coccoides (EREC and Clostridium leptum (CLEPT -groups in comparison with other blood groups. Conclusions Our novel finding indicates that the ABO blood group is one of the genetically determined host factors modulating the composition of the human intestinal microbiota, thus enabling new applications in the field of personalized nutrition and medicine.

Mäkivuokko Harri

2012-06-01

102

New Isolation Technique to Study Apoptosis in Human Intestinal Epithelial Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Intestinal epithelial cells derive from stem cells at the base of the crypt and migrate along the crypt-lumen axis. Their life is terminated as they reach the luminal surface where they detach and are shed. Intestinal epithelial cells show evidence of apoptosis in the region of shedding, and cell death is thought to resemble a form of apoptosis called detachment-induced cell death, or anoikis. Human intestinal epithelial cells die rapidly in vitro due to loss of anchorage during isolation, ma...

Grossmann, Johannes; Maxson, Julie M.; Whitacre, Cecilia M.; Orosz, David E.; Berger, Nathan A.; Fiocchi, Claudio; Levine, Alan D.

1998-01-01

103

Cooperation between MEF2 and PPAR? in human intestinal ?,?-carotene 15,15'-monooxygenase gene expression  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Vitamin A and its derivatives, the retinoids, are essential for normal embryonic development and maintenance of cell differentiation. ?, ?-carotene 15,15'-monooxygenase 1 (BCMO1) catalyzes the central cleavage of ?-carotene to all-trans retinal and is the key enzyme in the intestinal metabolism of carotenes to vitamin A. However, human and various rodent species show markedly different efficiencies in intestinal BCMO1-mediated carotene to retin...

Gong Xiaoming; Tsai Shu-Whei; Yan Bingfang; Rubin Lewis P

2006-01-01

104

Metabolism of the benzidine-based azo dye Direct Black 38 by human intestinal microbiota.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Benzidine-based azo dyes are proven mutagens and have been linked to bladder cancer. Previous studies have indicated that their initial reduction is the result of the azo reductase activity of the intestinal microbiota. Metabolism of the benzidine-based dye Direct Black 38 was examined by using a semicontinuous culture system that simulates the lumen of the human large intestine. The system was inoculated with freshly voided feces, and an active flora was maintained as evidenced by volatile f...

Manning, B. W.; Cerniglia, C. E.; Federle, T. W.

1985-01-01

105

High-Throughput Quantitative Analysis of the Human Intestinal Microbiota with a Phylogenetic Microarray?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Gut microbiota carry out key functions in health and participate in the pathogenesis of a growing number of diseases. The aim of this study was to develop a custom microarray that is able to identify hundreds of intestinal bacterial species. We used the Entrez nucleotide database to compile a data set of bacterial 16S rRNA gene sequences isolated from human intestinal and fecal samples. Identified sequences were clustered into separate phylospecies groups. Representative sequences from each p...

2009-01-01

106

Plesiomonas shigelloides Enters Polarized Human Intestinal Caco-2 Cells in an In Vitro Model System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study provides the first definitive evidence that the gram-negative bacterium Plesiomonas shigelloides adheres to and enters eukaryotic intestinal host cells in vitro. P. shigelloides is increasingly regarded as an emerging enteric pathogen and has been implicated in intestinal and extraintestinal infections in humans. However, the establishment of its true role in enteric disease has been hindered by inadequacies in experimental design, deficiencies in clinical diagnosis, and the lack o...

Theodoropoulos, Christina; Wong, Toh Hee; O Brien, Mark; Stenzel, Deborah

2001-01-01

107

New Isolation Technique to Study Apoptosis in Human Intestinal Epithelial Cells  

Science.gov (United States)

Intestinal epithelial cells derive from stem cells at the base of the crypt and migrate along the crypt-lumen axis. Their life is terminated as they reach the luminal surface where they detach and are shed. Intestinal epithelial cells show evidence of apoptosis in the region of shedding, and cell death is thought to resemble a form of apoptosis called detachment-induced cell death, or anoikis. Human intestinal epithelial cells die rapidly in vitro due to loss of anchorage during isolation, making primary culture of these cells a goal that has not yet been reached. However, the molecular mechanisms underlying this process of anoikis are largely unknown. In this study, a novel protocol for the rapid, temperature-controlled isolation of highly purified human colonic epithelial cells from surgical specimens is described. Using this method, early molecular events of anoikis in nontransformed epithelial cells were studied. Intestinal epithelial cells were isolated at the beginning of the apoptotic cascade, before the activation of caspase 3 family members and cleavage of poly(ADP-ribose) polymerase and DNA fragmentation. Elucidating the molecular mechanisms of detachment-induced cell death may facilitate the establishment of long-term primary cultures of human intestinal epithelial cells and enhance our understanding of homeostasis in the intestinal epithelium.

Grossmann, Johannes; Maxson, Julie M.; Whitacre, Cecilia M.; Orosz, David E.; Berger, Nathan A.; Fiocchi, Claudio; Levine, Alan D.

1998-01-01

108

Human intestinal tissue with adult stem cell properties derived from pluripotent stem cells.  

Science.gov (United States)

Genetically engineered human pluripotent stem cells (hPSCs) have been proposed as a source for transplantation therapies and are rapidly becoming valuable tools for human disease modeling. However, many applications are limited due to the lack of robust differentiation paradigms that allow for the isolation of defined functional tissues. Here, using an endogenous LGR5-GFP reporter, we derived adult stem cells from hPSCs that gave rise to functional human intestinal tissue comprising all major cell types of the intestine. Histological and functional analyses revealed that such human organoid cultures could be derived with high purity and with a composition and morphology similar to those of cultures obtained from human biopsies. Importantly, hPSC-derived organoids responded to the canonical signaling pathways that control self-renewal and differentiation in the adult human intestinal stem cell compartment. This adult stem cell system provides a platform for studying human intestinal disease in vitro using genetically engineered hPSCs. PMID:24936470

Forster, Ryan; Chiba, Kunitoshi; Schaeffer, Lorian; Regalado, Samuel G; Lai, Christine S; Gao, Qing; Kiani, Samira; Farin, Henner F; Clevers, Hans; Cost, Gregory J; Chan, Andy; Rebar, Edward J; Urnov, Fyodor D; Gregory, Philip D; Pachter, Lior; Jaenisch, Rudolf; Hockemeyer, Dirk

2014-06-01

109

Human Intestinal Tissue with Adult Stem Cell Properties Derived from Pluripotent Stem Cells  

Science.gov (United States)

Summary Genetically engineered human pluripotent stem cells (hPSCs) have been proposed as a source for transplantation therapies and are rapidly becoming valuable tools for human disease modeling. However, many applications are limited due to the lack of robust differentiation paradigms that allow for the isolation of defined functional tissues. Here, using an endogenous LGR5-GFP reporter, we derived adult stem cells from hPSCs that gave rise to functional human intestinal tissue comprising all major cell types of the intestine. Histological and functional analyses revealed that such human organoid cultures could be derived with high purity and with a composition and morphology similar to those of cultures obtained from human biopsies. Importantly, hPSC-derived organoids responded to the canonical signaling pathways that control self-renewal and differentiation in the adult human intestinal stem cell compartment. This adult stem cell system provides a platform for studying human intestinal disease in vitro using genetically engineered hPSCs.

Forster, Ryan; Chiba, Kunitoshi; Schaeffer, Lorian; Regalado, Samuel G.; Lai, Christine S.; Gao, Qing; Kiani, Samira; Farin, Henner F.; Clevers, Hans; Cost, Gregory J.; Chan, Andy; Rebar, Edward J.; Urnov, Fyodor D.; Gregory, Philip D.; Pachter, Lior; Jaenisch, Rudolf; Hockemeyer, Dirk

2014-01-01

110

Characterization of monocarboxylate transporter 6: expression in human intestine and transport of the antidiabetic drug nateglinide.  

Science.gov (United States)

Monocarboxylate transporter (MCT) 6, encoded by SLC16A5, is a member of the monocarboxylate transporter family. Nateglinide, an oral hypoglycemic agent, quickly reaches the maximal serum concentration after its premeal administration. Although the functional existence of uptake systems for nateglinide in the intestine has been demonstrated, these transport systems have not yet been identified at the molecular level. The aim of this study was to demonstrate the localization of MCT6 in the human small intestine and characterize the transport properties of nateglinide via MCT6. Immunohistochemical analysis of the human small intestine revealed that anti-MCT6 antiserum stained the luminal side of the epithelial cells. When expressed in Xenopus laevis oocytes, MCT6-mediated uptake of [(14)C]nateglinide was sensitive to extracellular pH and membrane potential. Furthermore, the K(t) value of nateglinide (45.9 ?M) for MCT6 was lower than those previously reported in Caco-2 cells and rat intestinal brush-border membrane vesicles. In addition, probenecid, fluorescein, valproic acid, and salicylic acid, which are inhibitors of nateglinide uptake in Caco-2 cells and rat intestine, did not inhibit the uptake of nateglinide via MCT6. These results suggest that MCT6 may play a role in the intestinal absorption of nateglinide, although other transporters are also likely involved. PMID:23935065

Kohyama, Noriko; Shiokawa, Hisae; Ohbayashi, Masayuki; Kobayashi, Yasuna; Yamamoto, Toshinori

2013-11-01

111

Defining the critical limit of oxygen extraction in the human small intestine.  

Science.gov (United States)

Although animal models have been used to characterize the relation between oxygen consumption and blood flow, reliable data have not been generated in the human small intestine. We perfused segments of human small intestine by using an ex vivo perfusion circuit that allowed precise manipulation of blood flow and perfusion pressure. Our goal was to define the critical level of intestinal blood flow necessary to maintain the metabolic needs of the tissue. Human small intestine (n = 5) tissue obtained at transplantation harvest was transported on ice to the laboratory. A 40-cm mid-jejunal segment was selected for perfusion, and appropriate inflow and outflow vessels were identified and cannulated. Perfusion with an autologous blood solution was initiated through an extracorporeal membrane oxygenation circuit. After a 30-minute equilibration period, arterial and venous blood gases were measured at varying flow rates while maintaining a constant hematocrit level. Arterial and venous oxygen content, arteriovenous oxygen difference (A-VO2 diff), and oxygen consumption (VO2) were then calculated. Our results demonstrated that at blood flows > 30 ml/min/100 g, VO2 is independent of blood flow (1.6 +/- 0.06 ml/min/100 g), and oxygen extraction is inversely related to flow. Below this blood flow rate of 30 ml/min/100 g, oxygen extraction does not increase further (6.3 +/- 0.3 vol%), and VO2 becomes flow dependent. This ex vivo preparation defines for the first time a threshold value of blood flow for small intestine below which oxygen consumption decreases (30 ml/min/100 g). Previous animal studies have correlated such a decrease in oxygen consumption with functional and histologic evidence of tissue injury. This "critical" flow rate in human intestine is similar to that found previously in canine and feline intestine, but lower than that of rodent species. PMID:8667504

Desai, T R; Sisley, A C; Brown, S; Gewertz, B L

1996-05-01

112

Decreased gastric emptying and gastrointestinal and intestinal transits of liquid after complete spinal cord transection in awake rats  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english We studied the effect of complete spinal cord transection (SCT) on gastric emptying (GE) and on gastrointestinal (GI) and intestinal transits of liquid in awake rats using the phenol red method. Male Wistar rats (N = 65) weighing 180-200 g were fasted for 24 h and complete SCT was performed between [...] C7 and T1 vertebrae after a careful midline dorsal incision. GE and GI and intestinal transits were measured 15 min, 6 h or 24 h after recovery from anesthesia. A test meal (0.5 mg/ml phenol red in 5% glucose solution) was administered intragastrically (1.5 ml) and the animals were sacrificed by an iv thiopental overdose 10 min later to evaluate GE and GI transit. For intestinal transit measurements, 1 ml of the test meal was administered into the proximal duodenum through a cannula inserted into a gastric fistula. GE was inhibited (P

F. de-A.A., Gondim; J.R.V., da-Graça; G.R., de-Oliveira; M.C.V., Rêgo; R.B.M., Gondim; F.H., Rola.

113

Bidirectional FcRn-dependent IgG transport in a polarized human intestinal epithelial cell line  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The MHC class I–related Fc receptor, FcRn, mediates the intestinal absorption of maternal IgG in neonatal rodents and the transplacental transport of maternal IgG in humans by receptor-mediated transcytosis. In mice and rats, expression of FcRn in intestinal epithelial cells is limited to the suckling period. We have recently observed, however, clear expression of FcRn in the adult human intestine, suggesting a function for FcRn in intestinal IgG transport beyond neonatal life in humans. We...

Dickinson, Bonny L.; Badizadegan, Kamran; Wu, Zhen; Ahouse, Jeremy C.; Zhu, Xiaoping; Simister, Neil E.; Blumberg, Richard S.; Lencer, Wayne I.

1999-01-01

114

Effect of Ceftaroline on Normal Human Intestinal Microflora?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ceftaroline is a new broad-spectrum cephalosporin being developed for the treatment of serious bacterial infections, including those caused by aerobic Gram-positive and Gram-negative bacteria. The purpose of the present study was to investigate the effect of administration of ceftaroline on the intestinal flora of healthy subjects. Twelve healthy subjects (6 males and 6 females), 20 to 41 years of age, received ceftaroline (600 mg) by intravenous infusion every 12 h (q12h) for 7 days. Plasma ...

Panagiotidis, Georgios; Ba?ckstro?m, Tobias; Asker-hagelberg, Charlotte; Jandourek, Alena; Weintraub, Andrej; Nord, Carl Erik

2010-01-01

115

Robust antiviral responses to enterovirus 71 infection in human intestinal epithelial cells.  

Science.gov (United States)

Enterovirus 71 (EV71) is a single-stranded RNA virus that belongs to Picornaviridae family. It causes the hand-foot-and-mouth disease and fatal neurological diseases in young children and infants. The mechanism of EV71 pathogenesis remains obscure. The intestinal tract is the initial site of EV71 replication, but no or only mild gastrointestinal symptoms are observed clinically, suggesting that host immune responses of the intestinal epithelium to EV71 may be unique, which, however, remains rarely investigated. In this study, we showed that human intestinal epithelial cells HT-29 were susceptible to EV71, and the infected cells exhibited cytopathic effects (CPEs) and were prone to apoptosis. TLR-7 and TLR-8 were induced significantly post infection and may be pivotal in the induction of IFN-? and host innate immune responses against EV71. Among proinflammatory responses in EV71-infected intestinal epithelial cells, IL-6, CCL5, and IP10 were up-regulated and may play a key role in intestinal pathogenicity. We examined extrinsic and intrinsic apoptotic pathways and found that both were activated in EV71 infection. The mitochondria-mediated intrinsic pathway may also be activated through Bid cleaved by active caspase-8. Robust induction of IFN-? in human intestinal epithelial cells contradicts the finding that IFN induction was suppressed in other types of the cells, suggesting that mild gastrointestinal symptoms may be the result of sufficient local antiviral inductions. Our study has demonstrated a unique way of antiviral responses in human gut different from other tissue cells in response to EV71, which may account for mild symptoms in intestinal tract. This finding will broaden our understanding of host defense mechanism and the pathogenesis of EV71 infection. PMID:23685430

Chi, Chuanzhen; Sun, Qiyu; Wang, Shuai; Zhang, Zerui; Li, Xue; Cardona, Carol J; Jin, Yu; Xing, Zheng

2013-09-01

116

Species differences in intestinal glucuronidation activities between humans, rats, dogs and monkeys.  

Science.gov (United States)

1.? Glucuronidation via UDP-glucuronosyltransferase (UGT) in the intestine has been reported to influence the pharmacokinetics (PK) of drugs; however, information concerning the differences in activity between species is limited. Here, we investigated the in vitro and in vivo activities of intestinal glucuronidation for 17 UGT substrates in humans, rats, dogs and monkeys. 2.? Although in vitro intrinsic clearance (CLint,u,UGT) in intestinal microsomes showed a good correlation between humans and laboratory animals, values tended to be lower in humans than in laboratory animals. The ratio of CLint,u,UGT in the absence and presence of bovine serum albumin differed between species. In vivo, the fraction of drug absorbed (FaFg) in humans correlated with that in dogs and monkeys, but not in rats. 3.? While an inverse correlation between CLint,u,UGT and FaFg was observed in each species, the CLint,u,UGT values in the intestinal microsomes corresponding to FaFg values in dogs were three to four times higher than in other animals. 4.? These results indicate the need for a degree of caution when extrapolating PK data from laboratory animals to humans. PMID:23962030

Furukawa, Takako; Naritomi, Yoichi; Tetsuka, Kazuhiro; Nakamori, Fumihiro; Moriguchi, Hiroyuki; Yamano, Katsuhiro; Terashita, Shigeyuki; Tabata, Kenji; Teramura, Toshio

2014-03-01

117

Human intestinal trefoil factor is expressed in human hypothalamus and pituitary: evidence for a novel neuropeptide.  

Science.gov (United States)

Human intestinal trefoil factor, hITF, a secretory polypeptide found mainly in the human gastrointestinal tract, is a member of the newly characterized trefoil factor or P-domain peptide family representing putative growth factors. Here we describe the identification of this gut peptide in the human brain and pituitary. With reverse transcriptase polymerase chain reaction, we were able to isolate and clone the transcript from human hypothalamus. An antibody generated against a synthetic peptide derived from the carboxyl terminus of hITF was used for immunohistochemical studies of appropriate tissue sections. Neurons expressing hITF were identified in two magnocellular hypothalamic nuclei, the paraventricular and periventricular nuclei. hITF polypeptide was also observed in Herring bodies of the neurohypophysis and in secretory cells of the adenohypophysis. Double immunostaining with antigrowth hormone antibody showed partial coexistence in a selected subpopulation of adenohypophysial cells. Localization of hITF in the hypothalamo-neurohypophysial system may suggest a modulatory action on the classical magnocellular nonapeptides vasopressin and oxytocin, and further indicates an adenohypophysial importance of this peptide. It is likely that hITF represents a novel neuropeptide of yet unknown function. PMID:8940297

Probst, J C; Zetzsche, T; Weber, M; Theilemann, P; Skutella, T; Landgraf, R; Jirikowski, G F

1996-11-01

118

Intestinal adaptation following resection.  

Science.gov (United States)

Intestinal adaptation is a natural compensatory process that occurs following extensive intestinal resection, whereby structural and functional changes in the intestine improve nutrient and fluid absorption in the remnant bowel. In animal studies, postresection structural adaptations include bowel lengthening and thickening and increases in villus height and crypt depth. Functional changes include increased nutrient transporter expression, accelerated crypt cell differentiation, and slowed transit time. In adult humans, data regarding adaptive changes are sparse, and the mechanisms underlying intestinal adaptation remain to be fully elucidated. Several factors influence the degree of intestinal adaptation that occurs post resection, including site and extent of resection, luminal stimulation with enteral nutrients, and intestinotrophic factors. Two intestinotrophic growth factors, the glucagon-like peptide 2 analog teduglutide and recombinant growth hormone (somatropin), are now approved for clinical use in patients with short bowel syndrome (SBS). Both agents enhance fluid absorption and decrease requirements for parenteral nutrition (PN) and/or intravenous fluid. Intestinal adaptation has been thought to be limited to the first 1-2 years following resection in humans. However, recent data suggest that a significant proportion of adult patients with SBS can achieve enteral autonomy, even after many years of PN dependence, particularly with trophic stimulation. PMID:24586019

Tappenden, Kelly A

2014-05-01

119

Smooth muscle expresses bone morphogenetic protein (Vgr-1/BMP-6) in human fetal intestine.  

Science.gov (United States)

During human fetal development, autocrine TGF-beta1 regulates the synthesis of specific collagen types by intestinal smooth muscle cells in an age-dependent manner. Vgr-1/BMP6, a member of the TGF-beta superfamily, modulates epithelial, endochondral and neural tissue development in mice: a related peptide is essential to gut morphogenesis in Drosophila. This is the first study to detect vgr-1/BMP-6 during human intestinal organogenesis. Polyclonal antibodies to the precursor and mature fragments of vgr-1 were used in immunohistochemical studies of human intestine at 15, 19 and 24 weeks' gestation. Immunoreactivity was detected with the antibody directed against the precursor portion of vgr-1. Only smooth muscle structures stained for vgr-1 including muscularis propria, muscularis mucosa and vasculature. BMP-6 mRNA was detected by RNase protection assay in cultured muscle cells from 11, 17 and 22 weeks' gestation. This study demonstrates vgr-1/BMP 6 expression in the developing human fetal intestine, exclusively in muscle. PMID:9925908

Perr, H A; Ye, J; Gitelman, S E

1999-03-01

120

Human intestinal parasites in the past: new findings and a review  

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Almost all known human specific parasites have been found in ancient feces. A review of the paleoparasitological helminth and intestinal protozoa findings available in the literature is presented. We also report the new paleoparasitologic findings from the examination performed in samples collected in New and Old World archaeological sites. New finds of ancylostomid, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Trichostrongylus spp., Diphyllobothrium latum, Hymenolepis ...

Gonçalves Marcelo Luiz Carvalho; Araújo Adauto; Ferreira Luiz Fernando

2003-01-01

 
 
 
 
121

The identification of peroxisome proliferator-activated receptor alpha-independent effects of oleoylethanolamide on intestinal transit in mice.  

Science.gov (United States)

Oleoylethanolamide (OEA) is an endogenous lipid produced in the intestine that mediates satiety by activation of peroxisome proliferator-activated receptor alpha (PPARalpha). OEA inhibits gastric emptying and intestinal motility, but the mechanism of action remains to be determined. We investigated whether OEA inhibits intestinal motility by activation of PPARalpha. PPARalpha immunoreactivity was examined in whole mount preparations of mouse gastrointestinal (GI) tract. The effect of OEA on motility was assessed in wildtype, PPARalpha, cannabinoid CB(1) receptor and CB(2) receptor gene-deficient mice and in a model of accelerated GI transit. In addition, the effect of OEA on motility was assessed in mice injected with the PPARalpha antagonist GW6471, transient receptor potential vanilloid 1 antagonist SB366791 or the glucagon-like peptide 1 antagonist exendin-3(9-39) amide. PPARalpha immunoreactivity was present in neurons in the myenteric and submucosal plexuses throughout the GI tract. OEA inhibited upper GI transit in a dose-dependent manner, but was devoid of an effect on whole gut transit or colonic propulsion. OEA-induced inhibition of motility was still present in PPARalpha, CB(1) and CB(2) receptor gene-deficient mice and in the presence of GW6471, SB366791 and exendin-3(9-39) amide, suggesting neither PPARalpha nor the cannabinoids and other likely receptors are involved in mediating the effects of OEA. OEA blocked stress-induced accelerated upper GI transit at a dose that had no effect on physiological transit. We show that PPARalpha is found in the enteric nervous system, but our results suggest that PPARalpha is not involved in the suppression of motility by OEA. PMID:19140957

Cluny, N L; Keenan, C M; Lutz, B; Piomelli, D; Sharkey, K A

2009-04-01

122

Intestinal transport of manganese from human milk, bovine milk and infant formula in rats.  

Science.gov (United States)

The transport of manganese from extrinsically labeled human milk, bovine milk and infant formula was studied by the everted intestinal sac method. Tissue/mucosal flux data indicated that transport of manganese into the intestinal tissue was significantly greater with bovine milk and formula than from human milk. Similarly, the total flux of manganese from the mucosal to serosal surface was less when human milk was used. Smaller molecular weight manganese binding ligands isolated from the milk samples enhanced the mucosal to tissue movement of manganese as contrasted to the higher molecular weight manganese binding ligands. Most significantly the data suggest that the transport and uptake of manganese is less in the presence of human milk and its isolated manganese fractions than it is in bovine milk or infant formula. PMID:6513722

Chan, W Y; Bates, J M; Rennert, O M; Mahmood, A; Torres-Pinedo, R

1984-12-10

123

Intestinal transport of manganese from human milk, bovine milk and infant formula in rats  

International Nuclear Information System (INIS)

The transport of manganese from extrinsically labeled human milk, bovine milk and infant formula was studied by the everted intestinal sac method. Tissue/mucosal flux data indicated that transport of manganese into the intestinal tissue was significantly greater with bovine milk and formula than from human milk. Similarly, the total flux of manganese from the mucosal to serosal surface was less when human milk was used. Smaller molecular weight manganese binding ligands isolated from the milk samples enhanced the mucosal to tissue movement of manganese as contrasted to the higher molecular weight manganese binding ligands. Most significantly the data suggest that the transport and uptake of manganese is less in the presence of human milk and its isolated manganese fractions than it is in bovine milk or infant formula. 15 references, 3 tables

1984-12-10

124

Immunocytochemical demonstration that human duodenal Brunner's glands may participate in intestinal defence.  

Science.gov (United States)

The immunocytochemical demonstration of IgA and IgM in some secretory units of human Brunner's glands, associated with the presence of secretory component in all secretory cells, indicates the possibility that these glands assist the function of the intestinal crypts in transporting immunoglobulins into the gut lumen. In addition, the presence of muramidase (lysozyme) in the cells of the secretory units suggests that Brunner's glands continuously secrete bactericidal enzyme, thus reinforcing the function of the Paneth cells as contributors to nonspecific defence (innate immunity) in the intestinal tract. PMID:8771411

Coutinho, H B; Robalinho, T I; Coutinho, V B; Amorin, A M; Almeida, J R; Filho, J T; Walker, E; King, G; Sewell, H F; Wakelin, D

1996-08-01

125

Monocarboxylate Transporter-Mediated Transport of ?-Hydroxybutyric Acid in Human Intestinal Caco-2 Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objectives of this study were to determine mRNA expression of monocarboxylate transporters (MCT) and to evaluate intestinal transport of the MCT substrates ?-hydroxybutyrate (GHB) and d-lactate in human intestinal Caco-2 cells. The presence of mRNA for MCT1, 2, 3, and 4 was observed in Caco-2 cells. The uptake of both GHB and d-lactate in Caco-2 cells was demonstrated to be pH- and concentration-dependent and sodium-independent. The uptake of GHB and d-lactate was best described by a Mic...

Lam, Wing Ki; Felmlee, Melanie A.; Morris, Marilyn E.

2010-01-01

126

Progreso en el conocimiento de la microbiota intestinal humana / Progress in the knowledge of the intestinal human microbiota  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish La aparición de nuevas técnicas de secuenciación así como el desarrollo de herramientas bioinformáticas han permitido no sólo describir la composición de la comunidad bacteriana que habita el tracto gastrointestinal, sino también las funciones metabólicas de las que proveen al huésped. La mayoría de [...] los miembros de esta amplia comunidad bacteriana pertenecen a Dominio Bacteria, aunque encontramos también Archaea y formas eucariotas y virus. Únicamente entre 7 y 9 de las 55 Phyla del Dominio Bacteria conocidos están presentes en flora fecal humana. Su mayoría pertenecen además a las Divisiones Bacteroidetes and Firmicutes, encontrando también Proteobacteria, Actinobacteria, Fusobacteria y Verrucomicrobia. Bacteroides, Faecalibacterium y Bifidobacterium son los Géneros más abundantes aunque su abundancia relativa es muy variable entre individuos. El análisis metagenómico de la flora intestinal ha permitido describir una colección de 5 millones de genes microbianos que codifican para aproximadamente 20.000 funciones biológicas relacionadas con la vida de las bacterias. El ecosistema intestinal humano puede clasificarse en torno a tres grupos de acuerdo a la abundancia relativa de tres Géneros: Bacteroides (enterotipo 1), Prevotella (enterotipo 2) y Ruminococcus (enterotype 3). Estos grupos han sido denominados "enterotipos" y su descripción sugiere que las variaciones entre individuos están estratificadas. Una vez descrita la composición bacteriana sería interesante establecer la relación entre la alteración de equilibrios ecológicos con estados de enfermedad que puedan desembocar en una novedosa vía terapéutica. Abstract in english New sequencing technologies together with the development of bioinformatics allow a description of the full spectrum of the microbial communities that inhabit the human intestinal tract, as well as their functional contributions to host health. Most community members belong to the domain Bacteria, b [...] ut Archaea, Eukaryotes (yeasts and protists), and Viruses are also present. Only 7 to 9 of the 55 known divisions or phyla of the domain Bacteria are detected in faecal or mucosal samples from the human gut. Most taxa belong to just two divisions: Bacteroidetes and Firmicutes, and the other divisions that have been consistently found are Proteobacteria, Actinobacteria, Fusobacteria, and Verrucomicrobia. Bacteroides, Faecalibacterium and Bifidobacterium are the most abundant genera but their relative proportion is highly variable across individuals. Full metagenomic analysis has identified more than 5 million non-redundant microbial genes encoding up to 20,000 biological functions related with life in the intestinal habitat. The overall structure of predominant genera in the human gut can be assigned into three robust clusters, which are known as "enterotypes". Each of the three enterotypes is identifiable by the levels of one of three genera: Bacteroides (enterotype 1), Prevotella (enterotype 2) and Ruminococcus (enterotype 3). This suggests that microbiota variations across individuals are stratified, not continuous. Next steps include the identification of changes that may play a role in certain disease states. A better knowledge of the contributions of microbial symbionts to host health will help in the design of interventions to improve symbiosis and combat disease.

Virginia, Robles-Alonso; Francisco, Guarner.

127

Human Carboxymethylenebutenolidase as a Bioactivating Hydrolase of Olmesartan Medoxomil in Liver and Intestine  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Olmesartan medoxomil (OM) is a prodrug type angiotensin II type 1 receptor antagonist widely prescribed as an antihypertensive agent. Herein, we describe the identification and characterization of the OM bioactivating enzyme that hydrolyzes the prodrug and converts to its pharmacologically active metabolite olmesartan in human liver and intestine. The protein was purified from human liver cytosol by successive column chromatography and was identified by mass spectrometry to be a carboxymethyl...

Ishizuka, Tomoko; Fujimori, Izumi; Kato, Mitsunori; Noji-sakikawa, Chisa; Saito, Motoko; Yoshigae, Yasushi; Kubota, Kazuishi; Kurihara, Atsushi; Izumi, Takashi; Ikeda, Toshihiko; Okazaki, Osamu

2010-01-01

128

Cytosolic and microsomal glutathione S-transferase isoenzymes in normal human liver and intestinal epithelium.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Glutathione S-transferases are a group of drug metabolising and detoxification enzymes. We have studied the distribution of four isoenzymes, acidic, basic, neutral, and microsomal GST in human liver, gall bladder, and small and large intestinal epithelium by immunohistochemistry. Antibodies were raised in rabbits to purified GST subunits and several formalin fixed paraffin sections of each human tissue studied using the peroxidase-antiperoxidase method. Staining density was graded from very s...

Hayes, P. C.; Harrison, D. J.; Bouchier, I. A.; Mclellan, L. I.; Hayes, J. D.

1989-01-01

129

Interaction of Cryptosporidium hominis and Cryptosporidium parvum with Primary Human and Bovine Intestinal Cells  

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Cryptosporidiosis in humans is caused by the zoonotic pathogen Cryptosporidium parvum and the anthroponotic pathogen Cryptosporidium hominis. To what extent the recently recognized C. hominis species differs from C. parvum is unknown. In this study we compared the mechanisms of C. parvum and C. hominis invasion using a primary cell model of infection. Cultured primary bovine and human epithelial intestinal cells were infected with C. parvum or C. hominis. The effects of the carbohydrate lecti...

Hashim, Amna; Mulcahy, Grace; Bourke, Billy; Clyne, Marguerite

2006-01-01

130

The angiogenic effect of probiotic Bacillus polyfermenticus on human intestinal microvascular endothelial cells is mediated by IL-8  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Angiogenesis is required for wound healing and repair, but dysregulated angiogenesis is involved in gastrointestinal inflammation. Bacillus polyfermenticus (B.P.) is a probiotic bacterium clinically used for a variety of intestinal disorders in East Asia. Here we investigated the effect of B.P. on angiogenesis of human intestinal microvascular endothelial cells (HIMECs) and wound healing in intestinal mucosa. Exposure of HIMECs to the conditioned medium of B.P. cultures (B.P. CM) increased ce...

Im, Eunok; Choi, Yoon Jeong; Kim, Cho Hee; Fiocchi, Claudio; Pothoulakis, Charalabos; Rhee, Sang Hoon

2009-01-01

131

PDX1 regulation of FABP1 and novel target genes in human intestinal epithelial Caco-2 cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The transcription factor pancreatic and duodenal homeobox 1 (PDX1) plays an essential role in pancreatic development and in maintaining proper islet function via target gene regulation. Few intestinal PDX1 targets, however, have been described. We sought to define novel PDX1-regulated intestinal genes. Caco-2 human intestinal epithelial cells were engineered to overexpress PDX1 and gene expression profiles relative to control cells were assessed. Expression of 80 genes significantly increased...

Chen, Chin; Fang, Rixun; Chou, Lin-chiang; Lowe, Anson W.; Sibley, Eric

2012-01-01

132

Influence of Camembert consumption on the composition and metabolism of intestinal microbiota: a study in human microbiota-associated rats.  

Science.gov (United States)

The objective of the present study was to evaluate the consequence of Camembert consumption on the composition and metabolism of human intestinal microbiota. Camembert cheese was compared with milk fermented by yoghurt starters and Lactobacillus casei as a probiotic reference. The experimental model was the human microbiota-associated (HM) rat. HM rats were fed a basal diet (HMB group), a diet containing Camembert made from pasteurised milk (HMCp group) or a diet containing fermented milk (HMfm group). The level of micro-organisms from dairy products was measured in faeces using cultures on a specific medium and PCR-temporal temperature gradient gel electrophoresis. The metabolic characteristics of the caecal microbiota were also studied: SCFA, NH3, glycosidase and reductase activities, and bile acid degradations. The results showed that micro-organisms from cheese comprised 10(5)-10(8) bacteria/g faecal sample in the HMCp group. Lactobacillus species from fermented milk were detected in HMfm rats. Consumption of cheese and fermented milk led to similar changes in bacterial metabolism: a decrease in azoreductase activity and NH3 concentration and an increase in mucolytic activities. However, specific changes were observed: in HMCp rats, the proportion of ursodeoxycholic resulting from chenodeoxycholic epimerisation was higher; in HMfm rats, alpha and beta-galactosidases were higher than in other groups and both azoreductases and nitrate reductases were lower. The results show that, as for fermented milk, Camembert consumption did not greatly modify the microbiota profile or its major metabolic activities. Ingested micro-organisms were able to survive in part during intestinal transit. These dairy products exert a potentially beneficial influence on intestinal metabolism. PMID:15469646

Lay, Christophe; Sutren, Malène; Lepercq, Pascale; Juste, Catherine; Rigottier-Gois, Lionel; Lhoste, Evelyne; Lemée, Riwanon; Le Ruyet, Pascale; Doré, Joël; Andrieux, Claude

2004-09-01

133

Exploring the Diversity of the Bifidobacterial Population in the Human Intestinal Tract?  

Science.gov (United States)

Although the health-promoting roles of bifidobacteria are widely accepted, the diversity of bifidobacteria among the human intestinal microbiota is still poorly understood. We performed a census of bifidobacterial populations from human intestinal mucosal and fecal samples by plating them on selective medium, coupled with molecular analysis of selected rRNA gene sequences (16S rRNA gene and internally transcribed spacer [ITS] 16S-23S spacer sequences) of isolated colonies. A total of 900 isolates were collected, of which 704 were shown to belong to bifidobacteria. Analyses showed that the culturable bifidobacterial population from intestinal and fecal samples include six main phylogenetic taxa, i.e., Bifidobacterium longum, Bifidobacterium pseudocatenulatum, Bifidobacterium adolescentis, Bifidobacterium pseudolongum, Bifidobacterium breve, and Bifidobacterium bifidum, and two species mostly detected in fecal samples, i.e., Bifidobacterium dentium and Bifidobacterium animalis subp. lactis. Analysis of bifidobacterial distribution based on age of the subject revealed that certain identified bifidobacterial species were exclusively present in the adult human gut microbiota whereas others were found to be widely distributed. We encountered significant intersubject variability and composition differences between fecal and mucosa-adherent bifidobacterial communities. In contrast, a modest diversification of bifidobacterial populations was noticed between different intestinal regions within the same individual (intrasubject variability). Notably, a small number of bifidobacterial isolates were shown to display a wide ecological distribution, thus suggesting that they possess a broad colonization capacity.

Turroni, Francesca; Foroni, Elena; Pizzetti, Paola; Giubellini, Vanessa; Ribbera, Angela; Merusi, Paolo; Cagnasso, Patrizio; Bizzarri, Barbara; de'Angelis, Gian Luigi; Shanahan, Fergus; van Sinderen, Douwe; Ventura, Marco

2009-01-01

134

Interaction of Campylobacter spp. and human probiotics in chicken intestinal mucus.  

Science.gov (United States)

Campylobacter is the most common cause of bacterial food-borne diarrhoeal disease throughout the world. The principal risk of human contamination is handling and consumption of contaminated poultry meat. To colonize poultry, Campylobacter adheres to and persists in the mucus layer that covers the intestinal epithelium. Inhibiting adhesion to the mucus could prevent colonization of the intestine. The aim of this study was to investigate in vitro the protective effect of defined commercial human probiotic strains on the adhesion of Campylobacter spp. to chicken intestinal mucus, in a search for alternatives to antibiotics to control this food-borne pathogen. The probiotic strains Lactobacillus rhamnosus GG and Propionibacterium freudenreichii ssp. shermanii JS and a starter culture strain Lactococcus lactis ssp. lactis adhered well to chicken intestinal mucus and were able to reduce the binding of Campylobacter spp. when the mucus was colonized with the probiotic strain before contacting the pathogen. Human-intended probiotics could be useful as prophylactics in poultry feeding for controlling Campylobacter spp. colonization. PMID:22672405

Ganan, M; Martinez-Rodriguez, A J; Carrascosa, A V; Vesterlund, S; Salminen, S; Satokari, R

2013-03-01

135

Beneficial effect of recombinant human growth hormone on the intestinal mucosa barrier of septic rats  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The objective of the present study was to investigate the effects of recombinant human growth hormone (rhGH) on the intestinal mucosa barrier of septic rats and explore its possible mechanism. Female Sprague-Dawley rats were randomized into three groups: control, Escherichia coli-induced sepsis (S) [...] and treatment (T) groups. Groups S and T were subdivided into subgroups 1d and 3d, respectively. Expression of liver insulin-like growth factor-1 (IGF-1) mRNA, Bcl-2 and Bax protein levels and the intestinal Bax/Bcl-2 ratio, and plasma GH and IGF-1 levels were determined. Histological examination of the intestine was performed and bacterial translocation was determined. rhGH significantly attenuated intestinal mucosal injuries and bacterial translocation in septic rats, markedly decreased Bax protein levels, inhibited the decrease of Bcl-2 protein expression and maintained the Bax/Bcl-2 ratio in the intestine. rhGH given after sepsis significantly improved levels of plasma GH (T1d: 1.28 ± 0.24; T3d: 2.14 ± 0.48 µg/L vs S1d: 0.74 ± 0.12; S3d: 0.60 ± 0.18 µg/L; P

Yi, C.; Cao, Y.; Wang, S.R.; Xu, Y.Z.; Huang, H.; Cui, Y.X.; Huang, Y..

136

Autoradiographic and enzyme histochemical studies of intestinal metaplasia in human stomach  

International Nuclear Information System (INIS)

The relationship between growth potency and alkaline phosphatase activity of intestinal metaplasia of human stomach was studied using enzyme histochemical and autoradiographic technique. Both alkaline phosphatase positive and negative glands were seen in the intestinal metaplasia. Two types of alkaline phosphatase positive glands were observed, one in which alkaline phosphatase positive cells were distributed from the lower part to the surface of the gland and the other in which alkaline phosphatase positive cells were localized only at the surface of the gland. "3H-Thymidine labelled cells in the former gland were localized only at the bottom but the labelled cells in the latter were distributed in the lower part of the gland. "3H-Thymidine labelled cells in alkaline phosphatase negative gland were distributed from the bottom to middle part of the gland. These results imply that the intestinal metaplasia in which cell proliferative zone was localized at the bottom of the gland showed alkaline phosphatase activity just like the activity in the small intestine, however the gland in which the cell proliferative zone was prolonged showed the alkaline phosphatase activity different from the small intestine. (author)

1982-01-01

137

Characterization of UDP-glucuronosyltransferases involved in glucuronidation of diethylstilbestrol in human liver and intestine.  

Science.gov (United States)

Diethylstilbestrol (DES), a synthetic estrogen, is famous for its carcinogenic effects. Human exposure to this compound can occur frequently through dietary ingestion and medical treatment. Glucuronidation has been demonstrated to be a predominant metabolic pathway for DES in human. Therefore, glucuronidation metabolism may have a significant impact on its toxicities, and it is essential to clarify this metabolic pathway. Accordingly, this in vitro study is designed to characterize the UGTs involved in DES glucuronidation and, furthermore, to identify the roles of individual isoforms in the reaction in liver and intestine. Human liver microsomes (HLM) displayed much higher potential for DES glucuronidation than human intestinal microsomes (HIM). The intrinsic clearances in HLM and HIM were demonstrated to be 459 and 14 ?L/min/mg protein, respectively. Assays with recombinant UGTs demonstrated that UGT1A1, -1A3, -1A8, and -2B7 could catalyze DES glucuronidation, among which UGT2B7 showed the highest affinity. Chemical inhibitors of UGT2B7 and UGT1A1/1A3 both displayed similar inhibition against the reaction in UGT2B7 and HLM. In addition, DES glucuronidation in individual HLM exhibited a large individual variability and strongly correlated to UGT2B7 activity. All evidence indicates that UGT2B7 may act as a major enzyme responsible for DES glucuronidation in human liver. For HIM, both UGT2B7 inhibitor and UGT1A1/1A3/1A8 inhibitor exerted moderate inhibition. It is suggested that although UGT2B7 contributes to DES glucuronidation in intestine, other UGTs may contribute equally. In summary, this study characterizes human UGTs involved in DES glucuronidation in human liver and intestine, which may be helpful for further study about DES-related toxicities. PMID:23126256

Zhu, Liangliang; Ge, Guangbo; Liu, Yong; Guo, Zhimou; Peng, Chengcheng; Zhang, Feng; Cao, Yunfeng; Wu, Jingjing; Fang, Zhongze; Liang, Xinmiao; Yang, Ling

2012-12-17

138

The bioavailability of apigenin-7-glucoside is influenced by human intestinal microbiota in rats.  

Science.gov (United States)

We investigated the impact of human intestinal microbiota on bioavailability of the flavone apigenin-7-glucoside (A7G) by comparing germ-free and human microbiota-associated (HMA) rats. First, the ability of the human intestinal microbiota to convert A7G was proven in vitro by incubating A7G with fecal suspensions. Apigenin, naringenin, and 3-(4-hydroxyphenyl)propionic acid were formed as main metabolites. After application of A7G to germ-free rats, apigenin, luteolin, and their conjugates were detected in urine and feces. In HMA rats, naringenin, eriodictyol, phloretin, 3-(3,4-dihydroxyphenyl)propionic acid, 3-(4-hydroxyphenyl)propionic acid, 3-(3-hydroxyphenyl)propionic acid, and 4-hydroxycinnamic acid in their free and conjugated forms were additionally formed. In whole-blood samples from germ-free and HMA rats, only apigenin conjugates and phloretin, respectively, were detected. The total excretion of A7G and its metabolites within 48 h was similarly low in both germ-free and HMA rats, with 11 and 13% of the A7G dose, respectively. In germ-free rats, A7G metabolites dominated by apigenin and its conjugates were mainly excreted with feces. In contrast, the compounds in HMA rats were predominantly recovered from urine, 3-(4-hydroxyphenyl)propionic acid being the main metabolite. The ability of selected gut bacteria and the host intestinal mucosa to deglycosylate A7G was tested using cell extracts. Apigenin was formed by cytosolic extracts of Eubacterium ramulus and Bacteroides distasonis and by the microsomal fraction of the small intestinal mucosa of rats. Overall, human intestinal microbiota largely contributed to A7G metabolism, indicating its influence on the bioactivity of flavones. PMID:19403720

Hanske, Laura; Loh, Gunnar; Sczesny, Silke; Blaut, Michael; Braune, Annett

2009-06-01

139

Human Intestinal Cells Modulate Conjugational Transfer of Multidrug Resistance Plasmids between Clinical Escherichia coli Isolates.  

DEFF Research Database (Denmark)

Bacterial conjugation in the human gut microbiota is believed to play a major role in the dissemination of antibiotic resistance genes and virulence plasmids. However, the modulation of bacterial conjugation by the human host remains poorly understood and there is a need for controlled systems to study this process. We established an in vitro co-culture system to study the interaction between human intestinal cells and bacteria. We show that the conjugation efficiency of a plasmid encoding an extended spectrum beta-lactamase is reduced when clinical isolates of Escherichia coli are co-cultured with human intestinal cells. We show that filtered media from co-cultures contain a factor that reduces conjugation efficiency. Protease treatment of the filtered media eliminates this inhibition of conjugation. This data suggests that a peptide or protein based factor is secreted on the apical side of the intestinal cells exposed to bacteria leading to a two-fold reduction in conjugation efficiency. These results show that human gut epithelial cells can modulate bacterial conjugation and may have relevance to gene exchange in the gut.

Machado, Ana Manuel; Sommer, Morten

2014-01-01

140

Similarity of hydrolyzing activity of human and rat small intestinal disaccharidases  

Directory of Open Access Journals (Sweden)

Full Text Available Tsuneyuki Oku¹, Kenichi Tanabe¹, Shigeharu Ogawa², Naoki Sadamori¹, Sadako Nakamura¹¹Graduate School of Human Health Science, University of Nagasaki, Siebold, Nagayo, Japan; ²Juzenkai Hospital, Kagomachi, Nagasaki, JapanBackground: The purpose of this study was to clarify whether it is possible to extrapolate results from studies of the hydrolyzing activity of disaccharidases from rats to humans.Materials and methods: We measured disaccharidase activity in humans and rats using identical preparation and assay methods, and investigated the similarity in hydrolyzing activity. Small intestinal samples without malignancy were donated by five patients who had undergone bladder tumor surgery, and homogenates were prepared to measure disaccharidase activity. Adult rat homogenates were prepared using small intestine.Results: Maltase activity was the highest among the five disaccharidases, followed by sucrase and then palatinase in humans and rats. Trehalase activity was slightly lower than that of palatinase in humans and was similar to that of sucrase in rats. Lactase activity was the lowest in humans, but was similar to that of palatinase in rats. Thus, the hydrolyzing activity of five disaccharidases was generally similar in humans and rats. The relative activity of sucrose and palatinase versus maltase was generally similar between humans and rats. The ratio of rat to human hydrolyzing activity of maltase, sucrase, and palatinase was 1.9–3.1, but this was not a significant difference. Leaf extract from Morus alba strongly inhibited the activity of maltase, sucrase, and palatinase, but not trehalase and lactase, and the degree of inhibition was similar in humans and rats. L-arabinose mildly inhibited sucrase activity, but hardly inhibited the activity of maltase, palatinase, trehalase and lactase in humans and rats. The digestibility of 1-kestose, galactosylsucrose, and panose by small intestinal enzymes was very similar between humans and rats.Conclusion: These results demonstrate that the digestibility of newly developed saccharide materials evaluated by rat small intestinal enzymes can substitute for evaluation using human enzymes.Keywords: disaccharidase, maltase, sucrase, trehalase, palatinase, digestibility

Oku T

2011-06-01

 
 
 
 
141

Probiotic supplementation decreases intestinal transit time: Meta-analysis of randomized controlled trials  

Directory of Open Access Journals (Sweden)

Full Text Available AIM: To determine the efficacy of probiotic supplementation on intestinal transit time (ITT and to identify factors that influence these outcomes. METHODS: A systematic review of randomized controlled trials (RCTs of probiotic supplementation that measured ITT in adults was conducted by searching MEDLINE and EMBASE using relevant key word combinations. Main search limits included RCTs of probiotic supplementation in healthy or constipated adults that measured ITT. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference (SMD of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses were conducted to examine the impact of moderator variables on ITT SMD. RESULTS: A total of 11 clinical trials with 13 treatment effects representing 464 subjects were included in this analysis. Probiotic supplementation was associated with decreased ITT in relation to controls, with an SMD of 0.40 (95%CI: 0.20-0.59, P < 0.001. Constipation (r2 = 39%, P = 0.01, higher mean age (r2 = 27%, P = 0.03, and higher percentage of female subjects (r2 = 23%, P < 0.05 were predictive of decreased ITT with probiotics in meta-regression. Subgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation and in older vs younger subjects [both SMD: 0.59 (95%CI: 0.39-0.79 vs 0.17 (95%CI: -0.08-0.42, P = 0.01]. Medium to large treatment effects were identified with Bifidobacterium Lactis (B. lactis HN019 (SMD: 0.72, 95%CI: 0.27-1.18, P < 0.01 and B. lactis DN-173 010 (SMD: 0.54, 95%CI: 0.15-0.94, P < 0.01 while other single strains and combination products yielded small treatment effects. CONCLUSION: Overall, short-term probiotic supplementation decreases ITT with consistently greater treatment effects identified in constipated or older adults and with certain probiotic strains.

Larry E Miller

2013-01-01

142

Purification and fermentation in vitro of sesaminol triglucoside from sesame cake by human intestinal microbiota.  

Science.gov (United States)

Sesaminol triglucoside (STG), the most abundant lignan glycoside existing in sesame cake/meal, has exhibited various biological activities. However, little information about its in vitro fermentation with intestinal microbiota is available. Therefore, the effect of STG from sesame cake on the fermentation of human fecal microbiota was evaluated. First, high-purity STG was successfully prepared from defatted sesame cake by extraction with 80% ethanol and simple purification procedures of polyamide column chromatography and Toyopearl HW-40S column chromatography. Then the influence of STG on intestinal microbiota was conducted by monitoring bacterial populations and analyzing the concentrations of short-chain fatty acids (SCFA). We found that STG could significantly induce an increase in numbers of Lactobacillus - Enterococcus group and Bifidobacterium in fermentation in vitro with human fecal microbiota, while it did not stimulate the bacterial growth of Eubacterium rectale - Clostridium coccoides group, Clostridium histolyticum group, and Bacteroides - Prevotella group. Furthermore, it was found that concentrations of formic, acetic, propionic, and butyric acids in STG culture increased significantly during the fermentation, and its total SCFA concentration was relatively higher than those of the control and glucose cultures at 6 and 12 h fermentation. Our findings provided further evidence for the importance of human intestinal bacteria in the bioactivity of STG and its metabolites in the maintenance of human health. PMID:23387872

Zhu, Xiuling; Zhang, Xin; Sun, Yongkang; Su, Di; Sun, Yi; Hu, Bing; Zeng, Xiaoxiong

2013-02-27

143

Hydrolysis of pyrethroids by human and rat tissues: Examination of intestinal, liver and serum carboxylesterases  

International Nuclear Information System (INIS)

Hydrolytic metabolism of pyrethroid insecticides in humans is one of the major catabolic pathways that clear these compounds from the body. Rodent models are often used to determine the disposition and clearance rates of these esterified compounds. In this study the distribution and activities of esterases that catalyze pyrethroid metabolism have been investigated in vitro using several human and rat tissues, including small intestine, liver and serum. The major esterase in human intestine is carboxylesterase 2 (hCE2). We found that the pyrethroid trans-permethrin is effectively hydrolyzed by a sample of pooled human intestinal microsomes (5 individuals), while deltamethrin and bioresmethrin are not. This result correlates well with the substrate specificity of recombinant hCE2 enzyme. In contrast, a sample of pooled rat intestinal microsomes (5 animals) hydrolyze trans-permethrin 4.5-fold slower than the sample of human intestinal microsomes. Furthermore, it is demonstrated that pooled samples of cytosol from human or rat liver are ? 2-fold less hydrolytically active (normalized per mg protein) than the corresponding microsomal fraction toward pyrethroid substrates; however, the cytosolic fractions do have significant amounts (? 40%) of the total esteratic activity. Moreover, a 6-fold interindividual variation in carboxylesterase 1 protein expression in human hepatic cytosols was observed. Human serum was shown to lack pyrethroid hydrolytic activity, but rat serum has hydrolytic activity that is attributed to a single CE isozyme. We purified the serum CE enzyme to homogeneity to determine its contribution to pyrethroid metabolism in the rat. Both trans-permethrin and bioresmethrin were effectively cleaved by this serum CE, but deltamethrin, esfenvalerate, alpha-cypermethrin and cis-permethrin were slowly hydrolyzed. Lastly, two model lipase enzymes were examined for their ability to hydrolyze pyrethroids. However, no hydrolysis products could be detected. Together, these results demonstrate that extrahepatic esterolytic metabolism of specific pyrethroids may be significant. Moreover, hepatic cytosolic and microsomal hydrolytic metabolism should each be considered during the development of pharmacokinetic models that predict the disposition of pyrethroids and other esterified compounds

2007-05-15

144

Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem  

Science.gov (United States)

The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core genome. Genome mining of the small-intestinal streptococci focused on functions playing an important role in the interaction of these streptococci in the small-intestinal ecosystem, including natural competence and nutrient-transport and metabolism. Analysis of the small-intestinal Streptococcus genomes predicts a high capacity to synthesize amino acids and various vitamins as well as substantial divergence in their carbohydrate transport and metabolic capacities, which is in agreement with observed physiological differences between these Streptococcus strains. Gene-specific PCR-strategies enabled evaluation of conservation of Streptococcus populations in intestinal samples from different human individuals, revealing that the S. salivarius strains were frequently detected in the small-intestine microbiota, supporting the representative value of the genomes provided in this study. Finally, the Streptococcus genomes allow prediction of the effect of dietary substances on Streptococcus population dynamics in the human small-intestine.

Van den Bogert, Bartholomeus; Boekhorst, Jos; Herrmann, Ruth; Smid, Eddy J.; Zoetendal, Erwin G.; Kleerebezem, Michiel

2013-01-01

145

Unique insights into the intestinal absorption, transit, and subsequent biodistribution of polymer-derived microspheres.  

Science.gov (United States)

Polymeric microspheres (MSs) have received attention for their potential to improve the delivery of drugs with poor oral bioavailability. Although MSs can be absorbed into the absorptive epithelium of the small intestine, little is known about the physiologic mechanisms that are responsible for their cellular trafficking. In these experiments, nonbiodegradable polystyrene MSs (diameter range: 500 nm to 5 µm) were delivered locally to the jejunum or ileum or by oral administration to young male rats. Following administration, MSs were taken up rapidly (? 5 min) by the small intestine and were detected by transmission electron microscopy and confocal laser scanning microscopy. Gel permeation chromatography confirmed that polymer was present in all tissue samples, including the brain. These results confirm that MSs (diameter range: 500 nm to 5 µm) were absorbed by the small intestine and distributed throughout the rat. After delivering MSs to the jejunum or ileum, high concentrations of polystyrene were detected in the liver, kidneys, and lungs. The pharmacologic inhibitors chlorpromazine, phorbol 12-myristate 13-acetate, and cytochalasin D caused a reduction in the total number of MSs absorbed in the jejunum and ileum, demonstrating that nonphagocytic processes (including endocytosis) direct the uptake of MSs in the small intestine. These results challenge the convention that phagocytic cells such as the microfold cells solely facilitate MS absorption in the small intestine. PMID:23922388

Reineke, Joshua J; Cho, Daniel Y; Dingle, Yu-Ting; Morello, A Peter; Jacob, Jules; Thanos, Christopher G; Mathiowitz, Edith

2013-08-20

146

Unique insights into the intestinal absorption, transit, and subsequent biodistribution of polymer-derived microspheres  

Science.gov (United States)

Polymeric microspheres (MSs) have received attention for their potential to improve the delivery of drugs with poor oral bioavailability. Although MSs can be absorbed into the absorptive epithelium of the small intestine, little is known about the physiologic mechanisms that are responsible for their cellular trafficking. In these experiments, nonbiodegradable polystyrene MSs (diameter range: 500 nm to 5 µm) were delivered locally to the jejunum or ileum or by oral administration to young male rats. Following administration, MSs were taken up rapidly (?5 min) by the small intestine and were detected by transmission electron microscopy and confocal laser scanning microscopy. Gel permeation chromatography confirmed that polymer was present in all tissue samples, including the brain. These results confirm that MSs (diameter range: 500 nm to 5 µm) were absorbed by the small intestine and distributed throughout the rat. After delivering MSs to the jejunum or ileum, high concentrations of polystyrene were detected in the liver, kidneys, and lungs. The pharmacologic inhibitors chlorpromazine, phorbol 12-myristate 13-acetate, and cytochalasin D caused a reduction in the total number of MSs absorbed in the jejunum and ileum, demonstrating that nonphagocytic processes (including endocytosis) direct the uptake of MSs in the small intestine. These results challenge the convention that phagocytic cells such as the microfold cells solely facilitate MS absorption in the small intestine.

Reineke, Joshua J.; Cho, Daniel Y.; Dingle, Yu-Ting; Morello, A. Peter; Jacob, Jules; Thanos, Christopher G.; Mathiowitz, Edith

2013-01-01

147

Cryptosporidium parvum Infection of Human Intestinal Xenografts in SCID Mice Induces Production of Human Tumor Necrosis Factor Alpha and Interleukin-8  

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The protozoan parasite Cryptosporidium parvum invades intestinal epithelial cells and can cause life-threatening diarrhea in immunocompromised individuals. Despite the clinical importance of this organism, much remains to be learned about the pathogenesis of C. parvum-induced diarrhea. To explore the role of the intestinal inflammatory response in C. parvum disease, using C. parvum oocysts we infected human intestinal xenografts in severe combined immunodeficient (SCID) mice. Seven days after...

Seydel, Karl B.; Zhang, Tonghai; Champion, Gretchen A.; Fichtenbaum, Carl; Swanson, Paul E.; Tzipori, Saul; Griffiths, Jeffrey K.; Stanley, Samuel L.

1998-01-01

148

Antimicrobial resistance in human oral and intestinal anaerobic microfloras.  

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In the present study we determined the resistance patterns of anaerobic bacteria from human saliva and stool specimens and investigated whether there were significant differences in resistance between outpatients and hospitalized patients, regardless of whether they had received antimicrobial agents. No bacterial strains resistant to ampicillin, piperacillin, cefoxitin, cefuroxime, imipenem, clindamycin, doxycycline, chloramphenicol, or metronidazole were isolated from the saliva samples. How...

Stark, C. A.; Edlund, C.; Sjo?stedt, S.; Kristensen, G.; Nord, C. E.

1993-01-01

149

Chemotherapy for cancer causes apoptosis that precedes hypoplasia in crypts of the small intestine in humans  

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BACKGROUND AND AIMS—The mechanism of gastrointestinal damage (mucositis) induced by cancer chemotherapy remains uncertain. The aims of this study were to define the time course and mechanism of small intestinal damage following chemotherapy in humans.?METHODS—Patients receiving chemotherapy underwent upper gastrointestinal endoscopy (a maximum of two per patient) with duodenal biopsy prior to chemotherapy and again at 1, 3, 5, and 16 days after chemotherapy. Tissue was taken for...

Keefe, D.; Brealey, J.; Goland, G.; Cummins, A.

2000-01-01

150

Antigens of gastric and intestinal mucous cells in human colonic tumours.  

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Using immunofluorescence methods, 3 antisera respectively stain 3 groups of mucous cells of the human gastrointestinal tract, showing specific antigens for each group of cells. The antigens of the first group, the M1 antigens, were principally associated with columnar cells of the gastric epithelium, the M2 antigens with mucous cells of gastric and Brünner's glands, and the M3 antigen with the goblet cells of the intestinal mucosa. The gastric M antigens normally detectable in stomach and du...

Bara, J.; Loisillier, F.; Burtin, P.

1980-01-01

151

Effect of vasoactive intestinal polypeptide on active and passive transport in the human jejunum.  

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The effect of intravenous vasoactive intestinal polypeptide (VIP) on normal transport mechanisms in the human jejunum in vivo was examined with the triple-lumen, steady-state perfusion technique. By using special test solutions that revealed different aspects of jejunal transport, we were able to evaluate the effect of VIP on specific transport processes, such as active bicarbonate absorption, active chloride secretion, and passive absorption or secretion of sodium chloride. At an infusion ra...

Davis, G. R.; Santa Ana, C. A.; Morawski, S. G.; Fordtran, J. S.

1981-01-01

152

Stem cell biology and clonal expansion in normal and adenomatous human intestinal crypts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Gastrointestinal cancer is thought to be primarily a disease of stem cells, whereby a tumorigenic stem cell clone can expand within an individual colonic crypt and then within the epithelium to form an adenoma - the pre-malignant lesion of the colon. However, data demonstrating stem cell populations and the dynamics of clonal expansion in human intestinal crypts is lacking. Naturally occurring, somatic clonal mutations in mitochondrial DNA were used to identify the progeny of a...

Humphries, A.

2012-01-01

153

Mapping of liver-enriched transcription factors in the human intestine  

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AIM: To investigate the gene expression pattern of hepatocyte nuclear factor 6 (HNF6) and other liver-enriched transcription factors in various segments of the human intestine to better understand the differentiation of the gut epithelium.METHODS: Samples of healthy duodenum and jejunum were obtained from patients with pancreatic cancer whereas ileum and colon was obtained from patients undergoing right or left hemicolectomy or (recto)sigmoid or rectal resection. All surgical specimens were s...

2010-01-01

154

Use of Stable Isotopes To Measure the Metabolic Activity of the Human Intestinal Microbiota?  

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The human intestinal microbiota is a complex biological system comprising a vast repertoire of microbes with considerable metabolic activity relevant to both bacterial growth and host health. Greater strides have been made in the analysis of microbial diversity than in the measurement of functional activity, particularly in vivo. Stable isotope probing offers a new approach by coupling measurements of metabolic activity with microbial identification. Using a low-enrichment labeling strategy i...

Reichardt, Nicole; Barclay, Andrew R.; Weaver, Lawrence T.; Morrison, Douglas J.

2011-01-01

155

Autoradiographic quantification of vasoactive intestinal peptide binding sites in sections from human blood mononuclear cell pellets  

Energy Technology Data Exchange (ETDEWEB)

Quantitative autoradiographic methods were utilized to characterize specific, high-affinity vasoactive intestinal peptide binding sites (Kd = 310 +/- 60 pmol/L; Bmax = 93 +/- 11 fmol/mg protein) in frozen sections obtained from a mononuclear cell pellet derived from 20 ml of human blood. The method is at least one order of magnitude more sensitive than conventional membrane binding techniques, and it has the potential for wide applications in studies of neuropeptide, biogenic amine, and drug binding in clinical samples.

Gutkind, J.S.; Kurihara, M.; Castren, E.; Saavedra, J.M.

1988-09-01

156

Prediction of Human Intestinal Absorption by GA Feature Selection and Support Vector Machine Regression  

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QSAR (Quantitative Structure Activity Relationships) models for the prediction of human intestinal absorption (HIA) were built with molecular descriptors calculated by ADRIANA.Code, Cerius2 and a combination of them. A dataset of 552 compounds covering a wide range of current drugs with experimental HIA values was investigated. A Genetic Algorithm feature selection method was applied to select proper descriptors. A Kohonen's self-organizing Neural Network (KohNN) map was used to split the who...

Aixia Yan; Zhi Wang; Zongyuan Cai

2008-01-01

157

Effect of broad-spectrum parenteral antibiotics on "colonization resistance" of intestinal microflora of humans.  

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Studies with animals have shown that the normal intestinal microflora protects against colonization by new strains ("colonization resistance") and that this protective effect may be related to the anaerobic component of the microflora. However, colonization resistance has not been shown in humans. We administered cefoxitin, piperacillin, cefoperazone, and aztreonam intravenously to healthy subjects for 9 days and monitored the acquisition of new isolates in the fecal flora. Seven of sixteen a...

Barza, M.; Giuliano, M.; Jacobus, N. V.; Gorbach, S. L.

1987-01-01

158

Immunocytochemical demonstration that human duodenal Brunner's glands may participate in intestinal defence.  

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The immunocytochemical demonstration of IgA and IgM in some secretory units of human Brunner's glands, associated with the presence of secretory component in all secretory cells, indicates the possibility that these glands assist the function of the intestinal crypts in transporting immunoglobulins into the gut lumen. In addition, the presence of muramidase (lysozyme) in the cells of the secretory units suggests that Brunner's glands continuously secrete bactericidal enzyme, thus reinforcing ...

Coutinho, H. B.; Robalinho, T. I.; Coutinho, V. B.; Amorin, A. M.; Almeida, J. R.; Filho, J. T.; Walker, E.; King, G.; Sewell, H. F.; Wakelin, D.

1996-01-01

159

Identification of astilbin metabolites produced by human intestinal bacteria using UPLC-Q-TOF/MS.  

Science.gov (United States)

Astilbin, mainly isolated from a commonly used herbal medicine, Smilax glabra Roxb (SGR), exhibits a variety of pharmacological activities and biological effects. It is metabolized by intestinal bacteria after oral administration which leads to the variation of ethnopharmacological profile of this traditional medicine. However, little is known on the interactions of this active compound with intestinal bacteria, which would be very helpful in unravelling how SGR works. In this study, different pure bacteria from human feces were isolated and were used to investigate their conversion capability of astilbin. Ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technique combined with Metabolynx(TM) software was used to analyze astilbin and its metabolites. The parent compound and two metabolites (quercetin and eriodictyol) were detected in the isolated bacterial samples compared with blank samples. Quercetin was present in Enterococcus sp. 8B, 8-2 and 9-2 samples. Eriodictyol was only identified in Enterococcus sp. 8B sample. The metabolic routes and metabolites of astilbin produced by the different intestinal bacteria are reported for the first time. This will be useful for the investigation of the pharmacokinetic study of astilbin in vivo and the role of different intestinal bacteria in the metabolism of natural compounds. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24399635

Zhao, Min; Xu, Jun; Qian, Dawei; Guo, Jianming; Jiang, Shu; Shang, Er-Xin; Duan, Jin-Ao

2014-07-01

160

Azoreductase activity of anaerobic bacteria isolated from human intestinal microflora.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A plate assay was developed for the detection of anaerobic bacteria that produce azoreductases. With this plate assay, 10 strains of anaerobic bacteria capable of reducing azo dyes were isolated from human feces and identified as Eubacterium hadrum (2 strains), Eubacterium spp. (2 species), Clostridium clostridiiforme, a Butyrivibrio sp., a Bacteroides sp., Clostridium paraputrificum, Clostridium nexile, and a Clostridium sp. The average rate of reduction of Direct Blue 15 dye (a dimethoxyben...

Rafii, F.; Franklin, W.; Cerniglia, C. E.

1990-01-01

 
 
 
 
161

Species differences in hepatic and intestinal metabolic activities for 43 human cytochrome P450 substrates between humans and rats or dogs.  

Science.gov (United States)

1. Prediction of human pharmacokinetics might be made more precise by using species with similar metabolic activities to humans. We had previously reported the species differences in intestinal and hepatic metabolic activities of 43 cytochrome P450 (CYP) substrates between cynomolgus monkeys and humans. However, the species differences between humans and rats or dogs had not yet been determined using comparable data sets with sufficient number of compounds. 2. Here, we investigated metabolic stabilities in intestinal and liver microsomes obtained from rats, dogs and humans using 43 substrates of human CYP1A2, CYP2J2, CYP2C, CYP2D6 and CYP3A. 3. Hepatic intrinsic clearance (CLint) values for most compounds in dogs were comparable to those in humans (within 10-fold), whereas in rats, those for the human CYP2D6 substrates were much higher and showed low correlation with humans. In dog intestine, as with human intestine, CLint values for almost all human CYP1A2, CYP2C, CYP2D6 substrates were not determined because they were very low. Intestinal CLint values for human CYP3A substrates in rats and dogs appeared to be lower for most of the compounds and showed moderate correlation with those in humans. 4. In conclusion, dogs showed the most similar metabolic activity to humans. PMID:23593983

Nishimuta, Haruka; Nakagawa, Tetsuya; Nomura, Naruaki; Yabuki, Masashi

2013-11-01

162

Intestinal Coccidia  

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Intestinal Coccidia are a subclass of Apicomplexa phylum. Eucoccidida are facultative heteroxenous, but some of them are monoxenous. They have sexual and asexual life cycle. Some coccidia are human pathogens, for example: Cryptosporidium: Cryptosporidiums has many species that are mammalian intestinal parasites.C. Parvum specie is a human pathogenic protozoa. Cryptosporidum has circle or ellipse shapes and nearly 4-6 mm. It is transmitted in warm seasons. Oocyst is obtained insexual life cycl...

2007-01-01

163

Stability of cephalosporin prodrug esters in human intestinal juice: implications for oral bioavailability.  

Science.gov (United States)

The levels of degradation of cefetamet pivoxil (CAT), cefuroxime axetil (CAE), and cefpodoxime proxetil (CPD) in 0.6 M phosphate buffer (pH 7.4) and human intestinal juice (pH 7.4) at 37 degreesC over 24 h were compared. Significant differences in the time courses of degradation and in the patterns of degradation products were observed. (i) The relative proportions of the Delta2- and Delta3-cephalosporins were roughly reversed in the two incubation media. In phosphate buffer, the major degradation product was the Delta2-cephalosporin (CAT = 61%; CAE = 74%; CPD = 85%), while in intestinal juice it was the Delta3-cephalosporin (CAT = 86%; CAE = 75%; CPD = 87%). (ii) Generally, the degradation of the prodrug esters progressed faster in intestinal juice than in phosphate buffer (e.g., for CAT the half-lives [t1/2s] were 0.78 and 4.3 h, respectively). (iii) The two diastereoisomers of CAE and CPD were degraded at different rates in intestinal juice (for the CAE diasteroisomers, t1/2s = 0.37 and 0.93 h; for the CPD diastereoisomers, t1/2s = 0.18 and 0.98 h) but were degraded at similar rates in phosphate buffer (for the CAE diastereoisomers, t1/2 = 1.6 h; for the CPD t1/2 diastereoisomers, = 2.2 h). It is concluded that (i) the Delta2 isomerization does not significantly affect the bioavailability of prodrug esters since enzymatic hydrolysis in the intestinal fluid proceeds mainly to the active Delta3-cephalosporin and (ii) the high degree of stereoselectivity of the enzymatic ester hydrolysis should make it possible to increase the bioavailabilities of certain prodrug esters (CAE, CPD) by using the more stable diasterioisomer. PMID:9756762

Stoeckel, K; Hofheinz, W; Laneury, J P; Duchene, P; Shedlofsky, S; Blouin, R A

1998-10-01

164

Supplementation transgenic cow's milk containing recombinant human lactoferrin enhances systematic and intestinal immune responses in piglets.  

Science.gov (United States)

Lactoferrin (LF) plays an important role in the body's immune system. However, the immunomodulatory effects of supplementation transgenic cow's milk containing recombinant human LF (rhLF) on the systemic and intestinal immune systems in infants remain unclear. Our laboratory has used genetic engineer to produce transgenic cow secreted rhLF. To assess the immune responses we took piglets as an animal model for infants. Eighteen piglets at 7 days of age were fed ordinary milk, 1:1 mix of ordinary and rhLF milk, or rhLF milk (LFM) for 30 days. The incidence of diarrhea in piglets in natural condition was observed. The protein abundances of immunoglobulin (Ig)G, IgA, IgM, IgE, histamine, interleukin (IL)-1?, IL-2, IL-4, IL-5, IL-8, IL-10, IL-12 interferon, tumor necrosis factor in the plasma, spleen or intestine were measured by enzyme-linked immunosorbent assay. Intestinal structure was assessed by hematoxylin and eosin. The mRNA levels of immune and allergy-related genes were measured by quantitative reverse transcription-polymerase chain reaction. The results showed that LFM-fed significantly reduced incidence of diarrhea, enhanced humoral immunity, T helper (Th) 1, and Th2 cell responses, improved the structure of the intestinal mucosal and did not induce food allergy. LFM increased mRNA levels of toll-like receptor 2 and nuclear factor-?B p65 and decreased that of FC?RI ?. In conclusion, rhLF-enriched formula could improve systematic and intestinal immune responses and did not elicit food allergies in neonatal piglets. PMID:24420858

Li, Qiuling; Hu, Wenping; Zhao, Jie; Wang, Jianwu; Dai, Yunping; Zhao, Yaofeng; Meng, Qingyong; Li, Ning

2014-04-01

165

Correlation between oral drug absorption in humans and apparent drug permeability coefficients in human intestinal epithelial (Caco-2) cells  

International Nuclear Information System (INIS)

Monolayers of a well differentiated human intestinal epithelial cell line, Caco-2, were used as a model to study passive drug absorption across the intestinal epithelium. Absorption rate constants (expressed as apparent permeability coefficients) were determined for 20 drugs and peptides with different structural properties. The permeability coefficients ranged from approximately 5 x 10- 8 to 5 x 10- 5 cm/s. A good correlation was obtained between data on oral absorption in humans and the results in the Caco-2 model. Drugs that are completely absorbed in humans had permeability coefficients greater than 1 x 10- 6 cm/s. Drugs that are absorbed to greater than 1% but less than 100% had permeability coefficients of 0.1-1.0 x 10- 6 cm/s while drugs and peptides that are absorbed to less than 1% had permeability coefficients of less than or equal to 1 x 10- 7 cm/s. The results indicate that Caco-2 monolayers can be used as a model for studies on intestinal drug absorption

1991-03-29

166

Otilonium bromide inhibits calcium entry through L-type calcium channels in human intestinal smooth muscle.  

Science.gov (United States)

Otilonium bromide (OB) is used as an intestinal antispasmodic. The mechanism of action of OB is not completely understood. As Ca(2+) entry into intestinal smooth muscle is required to trigger contractile activity, our hypothesis was that OB blocked Ca(2+) entry through L-type Ca(2+) channels. Our aim was to determine the effects of OB on Ca(2+), Na(+) and K(+) ion channels in human jejunal circular smooth muscle cells and on L-type Ca(2+) channels expressed heterologously in HEK293 cells. Whole cell currents were recorded using standard patch clamp techniques. Otilonium bromide (0.09-9 micromol L(-1)) was used as this reproduced clinical intracellular concentrations. In human circular smooth muscle cells, OB inhibited L-type Ca(2+) current by 25% at 0.9 micromol L(-1) and 90% at 9 micromol L(-1). Otilonium bromide had no effect on Na(+) or K(+) currents. In HEK293 cells, 1 micromol L(-1) OB significantly inhibited the expressed L-type Ca(2+) channels. Truncation of the alpha(1C) subunit C and N termini did not block the inhibitory effects of OB. Otilonium bromide inhibited Ca(2+) entry through L-type Ca(2+) at concentrations similar to intestinal tissue levels. This effect may underlie the observed muscle relaxant effects of the drug. PMID:15086870

Strege, P R; Evangelista, S; Lyford, G L; Sarr, M G; Farrugia, G

2004-04-01

167

The immunohistochemical demonstration of chymase and tryptase in human intestinal mast cells.  

Science.gov (United States)

An immunohistochemical double-labelling technique for the simultaneous identification of mast cells containing tryptase alone (MCT) or chymase together with tryptase (MCTC) was evaluated quantitatively using two monoclonal antibodies, mAb 1222A (antitryptase) and mAb 1254B (antichymase). Saturation conditions were established for the binding of the antibodies to the mast cell enzymes by counting labelled mast cells in consecutive sections of normal human intestine incubated with serial dilutions of the antibodies. When, under such conditions, the antitryptase was applied after saturation with mAb 1254B, the reproducibility of the double-labelling procedure was excellent. MCT were located preferentially in the intestinal mucosa but, in contrast to what has previously been reported, they were not the predominant type of mast cell at this site. The percentage of MCT of the total number of immunopositive mast cells varied considerably in the colonic mucosa (7-67%, average 30%), while this was not the case in the small intestinal mucosa (5-26%, average 10%). Mast cell chymase, unlike tryptase, was not recognized by the antichymase antibody after aldehyde fixation and a higher apparent fraction of MCT therefore occurred after double labelling. These findings suggest that the proteinase composition of human mast cells, unlike that of murine mast cells, should not be taken as evidence of phenotypic heterogeneity. Taken together with previous observations, they suggest instead that the lack of chymase may be related to functional activity or stage of maturation of the mast cells. PMID:7960936

Aldenborg, F; Enerbäck, L

1994-07-01

168

Colonization resistance of the human intestinal microflora: testing the hypothesis in normal volunteers.  

Science.gov (United States)

Colonization resistance is the mechanism whereby the intestinal microflora protects itself against incursion by new and often harmful microorganisms. Some authors have claimed that colonization resistance is related to the integrity of the anaerobic flora, but this point has not been established in humans. In previous studies in our laboratory cefoxitin, piperacillin, cefoperazone or aztreonam were administered intravenously to healthy volunteers in order to study changes in the intestinal flora and acquisition of new strains. Seven of 16 antibiotic-treated subjects were colonized with gram-negative bacilli, but no correlation was observed between this colonization and the suppression of either anaerobes or any other component of the fecal flora. Marked strains of Escherichia coli and Pseudomonas aeruginosa were also administered by mouth in order to test acquisition of new bacteria. The fed bacteria were found in the stools of both antibiotic-treated and control subjects; the antibiotics had no apparent influence on the ability of these strains to colonize the intestinal tract. Our work, along with findings of others, supports the concept that colonization resistance occurs in humans and is diminished by antibiotic administration. However, it does not support the hypothesis that colonization resistance is related to the anaerobic microflora. PMID:3132394

Gorbach, S L; Barza, M; Giuliano, M; Jacobus, N V

1988-02-01

169

Yersinia pseudotuberculosis induces transcytosis of nanoparticles across human intestinal villus epithelium via invasin-dependent macropinocytosis.  

Science.gov (United States)

Crohn's disease is characterized by a defect in intestinal barrier function, where bacteria are considered the most important inflammation-driving factor. Enteric bacteria, including E. coli and Yersinia spp, affect tight junctions in enterocytes, but little is known about bacterial effects on the transcellular pathway. Our objective was to study the short-term effects of Y. pseudotuberculosis on uptake of nanoparticles across human villus epithelium. Monolayers of human colon epithelium-derived Caco-2 cells and biopsies of normal human ileum were studied after 2 h exposure to Y. pseudotuberculosis expressing (inv+) or lacking (inv-) the bacterial adhesion molecule, invasin. Transepithelial transport of fluorescent nanoparticles (markers of transcytosis) was quantified by flow cytometry, and mechanisms explored by using inhibitors of endocytosis. Epithelial expressions of beta1-integrin and particle uptake pathways were studied by confocal microscopy. The paracellular pathway was assessed by electrical resistance (TER), mannitol flux, and expression of tight junction proteins occludin and caludin-4 by confocal microscopy. Inv+ Y. pseudotuberculosis adhered to the apical surface of epithelial cells and induced transcytosis of exogenous nanoparticles across Caco-2 monolayers (30-fold increase, P<0.01) and ileal mucosa (268+/-47% of control; P<0.01), whereas inv bacteria had no effect on transcytosis. The transcytosis was concentration-, particle size- and temperature-dependent, and possibly mediated via macropinocytosis. Y. pseudotuberculosis also induced apical expression of beta1-integrin on epithelial cells. A slight drop in TER was seen after exposure to inv+ Y. pseudotuberculosis, whereas mannitol flux and tight junction protein expression was unchanged. In summary, Y. pseudotuberculosis induced apical expression of beta1-integrin and stimulated uptake of nanoparticles via invasin-dependent transcytosis in human intestinal epithelium. Our findings suggest that bacterial factors may initiate transcytosis of luminal exogenous particles across human ileal mucosa, thus presenting a novel mechanism of intestinal barrier dysfunction. PMID:18810251

Ragnarsson, Eva G E; Schoultz, Ida; Gullberg, Elisabet; Carlsson, Anders H; Tafazoli, Farideh; Lerm, Maria; Magnusson, Karl-Eric; Söderholm, Johan D; Artursson, Per

2008-11-01

170

Studies on the determination of extracellular galactosyltransferase in human intestinal tissue  

International Nuclear Information System (INIS)

The determination of extracellular galactosyl transferase (EC 2.4.1.38) activity in human intestinal tissue by assessment of the incorporation of label after incubation with UDP["3H]galactose was evaluated. Intestinal biopsy specimens were incubated with membrane-permeable L-[1-"1"4C]fucose and non-permeable UDP-D-[6-"3H]galactose (UDP["3H]Gal). Comparison of the amounts of "3H- and "1"4C-label incorporated into subcellular fractions showed uptake and incorporation of galactose formed by the hydrolysis of UDP["3H]Gal by brush-border enzymes. The results indicate that incorporation of galactose after incubation of the tissue with UDP["3H]Gal is not exclusively attributable to extracellular galactosyl transferase. (Auth.)

1981-01-22

171

Human Capital Formation during Communism and Transition: Evidence from Bulgaria  

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Is it true that communist countries had well-developed human capital, or is it just a myth? What were human capital stocks at the beginning of transition to market economy? What happened to human capital formation during the transition? We attempt to answer these questions using evidence from Bulgaria. This is also a story about how a communist government had coped with labour market problems in a small closed economy. Unfortunately, during communism, there had been quite insufficient public ...

2005-01-01

172

Transport of thalidomide by the human intestinal caco-2 monolayers.  

Science.gov (United States)

Studies in patients have indicated that the oral absorption of thalidomide is considerably variable at high doses (>200 mg/day). The aim of this study was to investigate the transport of racemic thalidomide using human colon cancer cell line (Caco-2) monolayers, which have been widely used to investigate drug permeability. A typical 21-day protocol was used to prepare Caco-2 monolayers. Thalidomide was determined by a validated high performance liquid chromatography method with ultraviolet detection. The integrity of Caco-2 monolayer was confirmed when the transepithelial electrical resistance (TEER) exceeded 300 Ohmz . cm2, and the leakage of 14C-manitol was <1% per hour. Uptake of thalidomide by Caco-2 cells was very limited (up to 2.1%). The transport of thalidomide appeared to be linear up to 1 hr. Our study indicated that the permeability coefficients (Papp) of thalidomide at 2.5-300 microM from the apical (AP) to basolateral (BL) and from BL to AP side was 2-6 x 10(-5) cm/sec, with a marked decrease in Papp values from AP to BL at increased thalidomide concentration. The transport of thalidomide was sodium-, temperature- and pH-dependent, as replacement of extracellular sodium chloride or reducing temperature and apical pH can result in significant decreases in the Papp values. Additional data indicated that transport of thalidomide is energy-dependent, as it was significantly (P < 0.05) inhibited by the ATP inhibitors, sodium azide and 2,4-dinitrophenol. In addition, DL-glutamic acid, cytidine, diprodomole, papaverine, quinidine, and cyclophosphamide significantly (P < 0.05) inhibited the transport of thalidomide, while the P-glycoprotein inhibitor verapamil and other nucleosides and nucleotides such as thymidine and guanine had no effect. These results indicated that thalidomide was rapidly transported by Caco-2 monolayers, and this might involve a saturable energy-dependent transporter. PMID:16010862

Zhou, Shufeng; Li, Yan; Kestell, Phillip; Schafer, Peter; Chan, Eli; Paxton, James W

2005-01-01

173

Human intestinal parasites in non-biting synanthropic flies in Ogun State, Nigeria.  

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Filth-feeding and breeding, non-biting synanthropic flies have been incriminated in the dissemination of human enteropathogens in the environment. This study determined the species of non-biting synanthropic flies associated with four filthy sites in Ilishan, Ogun State, southwest Nigeria, and assessed their potentials for mechanical transmission of human intestinal parasites. 7190 flies identified as Musca domestica (33.94%), Chrysomya megacephala (26.01%), Musca sorbens (23.23%), Lucilia cuprina (8.76%), Calliphora vicina (4.59%), Sarcophaga sp. (2.78%) and Fannia scalaris (0.70%) were examined for human intestinal parasites by the formol-ether concentration and modified Ziehl-Neelsen techniques. Eggs of the following parasites: Ascaris lumbricoides (34.08%), Trichuris trichiura (25.87%), hookworms (20.45%), Taenia sp. (2.36%), Hymenolepis nana (1.11%), Enterobius vermicularis (0.56%), Strongyloides stercoralis (larvae; 3.89%) and cysts of Entamoeba histolytica/dispar (27.26%), Entamoeba coli (22.67%), Giardia lamblia (3.34%) and Cryptosporidium sp. (1.81%) were isolated from the body surfaces and or gut contents of 75.24% of 719 pooled fly batches. The helminths A. lumbricoides and T. trichiura and the protozoans, E. histolytica/dispar and E. coli were the dominant parasites detected, both on body surfaces and in the gut contents of flies. C. megacephala was the highest carrier of parasites (diversity and number). More parasites were isolated from the gut than from body surfaces (P < 0.05). Flies from soiled ground often carried more parasites than those from abattoir, garbage or open-air market. Synanthropic fly species identified in this study can be of potential epidemiological importance as mechanical transmitters of human intestinal parasites acquired naturally from filth and carried on their body surfaces and or in the gut, because of their vagility and feeding mechanisms. PMID:23290716

Adenusi, Adedotun Adesegun; Adewoga, Thomas O Sunday

2013-01-01

174

In Vitro Modulation of Human Intestinal Microbiota by Mannoligosaccharides Synthesized from Amorphophallus muelleri Glucomannan  

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Full Text Available The corms of Amorphophallus muelleri Blume contain a large amount of glucomannan, a kind of polysaccharide that are commonly consumed by people as gelly foods. In order to improve the beneficial properties of glucomannan, we previously have established the enzymatic process to produce the mannoligosaccharides from flour of glucomannan using microbial mannanase. The effects of mannoligosaccharides on the growth modulation of human intestinal microbiota were investigated in this study. A set of in vitro single batch culture experiment was conducted to study the effect of mannooligosaccharides on human-origin Lactobacillus fermentum AA0014 and Lactobacillus plantarum FU0811. A modified MRS medium containing 10% (w/v sucrose, glucomannan, and mannoligosaccharide was used instead of glucose as carbon source. The results showed the highest growth rate (0.13 h-1 with both L. fermentum AA0014 and L. plantarum FU0811 in the presence of mannooligosaccharides. We confirmed this result by a similar in vitro experiment using human fecal samples of six healthy adults as innocula and analyzed the microbial population by fluorescence in situ hybridization (FISH. Lactobacilli were proliferated higher in the presence of mannoligosaccharide than other carbon sources, yielding the microbial proportion as much of 10.9% of total microbiota. Overall, this study demonstrated the potential use of mannoligosaccharides synthesized from A. muelleri glucomannan as prebiotic candidate of modulating the beneficial human intestinal microbiota.

ACHMAD DINOTO

2013-11-01

175

Developmental changes in vasoactive intestinal polypeptide immunoreactivity in the human paravertebral ganglia.  

Science.gov (United States)

Vasoactive intestinal polypeptide (VIP) belongs to the glucagon-secretin family of polypeptides and possesses numerous functions. Its existence in the mammalian central and peripheral nervous system has been widely documented. However, there are no reports on the developmental aspects of VIP-like immunoreactivity (VIP-IR) in the human postganglionic sympathetic neurons. In this study the availability and distribution of vasoactive intestinal polypeptide has been localized in human stellate ganglia neurons and nerve fibers from neonates, children and adults using the immunohistochemical method. In neonatal ganglia VIP-immunoreactive postganglionic neurons were revealed in a marked population compared to others age-groups. These nerve cells are both small and large in size and are distributed in small clusters or singly in the area of ganglia sections. In children, VIP-IR in ganglionic neurons decreases. In adult stellate ganglia, VIP-immunoreactive postganglionic neurons rarely occur. In ganglia of an individual human only varicosities of VIP-positive nerve fibers were observed. These results provide the age-dependent reduction of VIP-like immunoreactivity in human stellate ganglia neurons and suggest the different role of this peptide in the function of sympathetic ganglia neurons with age. PMID:10609054

Roudenok, V; Kühnel, W; Rogov, Y; Nerovnja, A

1999-12-01

176

Tryptophan from human milk induces oxidative stress and upregulates the Nrf-2-mediated stress response in human intestinal cell lines.  

Science.gov (United States)

Chemical screening of digested human milk protein using the oxygen radical absorbance capacity (ORAC(FL)) antioxidant assay confirmed the presence of a peptide fraction (PF23) with high antioxidant activity [5.53 mmol Trolox equivalents (TE)/g] that contained tryptophan as a main component. We evaluated the effects of both PF23 and tryptophan alone on the modulation of oxidative stress in cultured intestinal cells using a dichlorofluorescein diacetate probe. Despite the high ORAC(FL) value, PF23 enhanced (P glutathione peroxidase 2. We conclude that tryptophan-induced oxidative stress associated with tryptophan-containing milk peptides induces an adaptive response that involves the activation of the antioxidant responsive signaling pathway in intestinal cells. PMID:21677072

Elisia, Ingrid; Tsopmo, Apollinaire; Friel, James K; Diehl-Jones, William; Kitts, David D

2011-08-01

177

High content analysis of cytotoxic effects of pDMAEMA on human intestinal epithelial and monocyte cultures  

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Poly(2-(dimethylamino ethyl)methacrylate) (pDMAEMA) is a cationic polymer with potential as an antimicrobial agent and as a non-viral gene delivery vector. The aim was to further elucidate the cytotoxicity of a selected pDMAEMA low molecular weight (MW) polymer against human U937 monocytes and Caco-2 intestinal epithelial cells using a novel multi-parameter high content analysis (HCA) assay and to investigate histological effects on isolated rat intestinal mucosae. Seven parameters of cytot...

Rawlinson, Lee-anne Betty; O Brien, Peter J.; Brayden, David James

2010-01-01

178

Allergen-IgE complexes trigger CD23-dependent CCL20 release from human intestinal epithelial cells  

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In food allergic individuals, exposure to food allergens by the oral route can trigger immediate (within minutes) local hypersensitivity reactions in the intestine followed by a late-phase inflammatory response. Previous work has shown that CD23 is constitutively expressed by human intestinal epithelial cells and mediates the uptake of allergen-IgE complexes. We hypothesized that allergen-IgE complexes could also signal via CD23 to trigger an inflammatory cascade in the local environment. Sti...

Li, Hongxing; Chehade, Mirna; Liu, Weicheng; Xiong, Huabao; Mayer, Lloyd; Berin, M. Cecilia

2007-01-01

179

Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem  

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The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core geno...

2013-01-01

180

Regulation of interleukin-8 secretion in human intestinal epithelial Caco-2 cells by alpha-humulene.  

Science.gov (United States)

It is well known that various cytokines such as interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha are expressed and secreted from intestinal epithelial cells and that these cytokines affect the immune cells beneath the intestinal epithelial monolayers. As the secretion of these cytokines is likely to be regulated by food-derived substances, we focused on those food substances which regulate the secretion of IL-8 in human intestinal epithelial Caco-2 cells. 72 food samples extracted with 40% ethanol were tested, and the extracts of peppermint and dokudami significantly increased the IL-8 secretion. Among the compounds known to be contained in peppermint and dokudami, alpha-humulene substantially increased the IL-8 secretion.alpha-Humulene had no significant effect on the secretion of such other soluble factors as TNF-alpha, IL-1beta, IL-6, or NGF, suggesting that the effect of alpha-humulene was specific for IL-8 secretion. The expression level of IL-8 mRNA was significantly increased by treating with alpha-humulene. These results suggest that the secretion of IL-8 by alpha-humulene is regulated at the transcriptional level. PMID:15630185

Satsu, Hideo; Matsuda, Tomoko; Toshimitsu, Takayuki; Mori, Akira; Mae, Tatsumasa; Tsukagawa, Misuzu; Kitahara, Mikio; Shimizu, Makoto

2004-01-01

 
 
 
 
181

Specific-sized Hyaluronan Fragments Promote Expression of Human ?-Defensin 2 in Intestinal Epithelium*  

Science.gov (United States)

Hyaluronan (HA) is a glycosaminoglycan polymer found in the extracellular matrix of virtually all mammalian tissues. Recent work has suggested a role for small, fragmented HA polymers in initiating innate defense responses in immune cells, endothelium, and epidermis through interaction with innate molecular pattern recognition receptors, such as TLR4. Despite these advances, little is known regarding the effect of fragmented HA at the intestinal epithelium, where numerous pattern recognition receptors act as sentinels of an innate defense response that maintains epithelial barrier integrity in the presence of abundant and diverse microbial challenges. Here we report that HA fragments promote expression of the innate antimicrobial peptide human ?-defensin 2 (H?D2) in intestinal epithelial cells. Treatment of HT-29 colonic epithelial cells with HA fragment preparations resulted in time- and dose-dependent up-regulated expression of H?D2 protein in a fragment size-specific manner, with 35-kDa HA fragment preparations emerging as the most potent inducers of intracellular H?D2. Furthermore, oral administration of specific-sized HA fragments promotes the expression of an H?D2 ortholog in the colonic epithelium of both wild-type and CD44-deficient mice but not in TLR4-deficient mice. Together, our observations suggest that a highly size-specific, TLR4-dependent, innate defense response to fragmented HA contributes to intestinal epithelium barrier defense through the induction of intracellular H?D2 protein.

Hill, David R.; Kessler, Sean P.; Rho, Hyunjin K.; Cowman, Mary K.; de la Motte, Carol A.

2012-01-01

182

Metabolism of the benzidine-based azo dye Direct Black 38 by human intestinal microbiota  

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Benzidine-based azo dyes are proven mutagens and have been linked to bladder cancer. Previous studies have indicated that their initial reduction is the result of the azo reductase activity of the intestinal microbiota. Metabolism of the benzidine-based dye Direct Black 38 was examined by using a semicontinuous culture system that simulates the lumen of the human large intestine. The system was inoculated with freshly voided feces, and an active flora was maintained as evidenced by volatile fatty acid and gas production. Within 7 days after exposure to the dye, the following metabolites were isolated and identified by gas chromatography - mass spectrometry: benzidine, 4-aminobiphenyl, monoacetylbenzidine, and acetylaminobiphenyl. Benzidine reached its peak level after 24 h, accounting for 39.1% of the added dye. Its level began to decline, and by day 7 the predominant metabolite was acetylaminobiphenyl, which accounted for 51.1% of the parent compound. Formation of the deaminated and N-acetylated analogs of benzidine, which have enhanced mutagenicity and lipophilicity, previously has not been attributed to the intestinal microbiota.

Manning, B.W.; Cerniglia, C.E.; Federle, T.W.

1985-07-01

183

Exogenous HIV-1 Nef Upsets the IFN-?-Induced Impairment of Human Intestinal Epithelial Integrity  

Science.gov (United States)

Background The mucosal tissues play a central role in the transmission of HIV-1 infection as well as in the pathogenesis of AIDS. Despite several clinical studies reported intestinal dysfunction during HIV infection, the mechanisms underlying HIV-induced impairments of mucosal epithelial barrier are still unclear. It has been postulated that HIV-1 alters enterocytic function and HIV-1 proteins have been detected in several cell types of the intestinal mucosa. In the present study, we analyzed the effect of the accessory HIV-1 Nef protein on human epithelial cell line. Methodology/Principal Findings We used unstimulated or IFN-?-stimulated Caco-2 cells, as a model for homeostatic and inflamed gastrointestinal tracts, respectively. We investigated the effect of exogenous recombinant Nef on monolayer integrity analyzing its uptake, transepithelial electrical resistance, permeability to FITC-dextran and the expression of tight junction proteins. Moreover, we measured the induction of proinflammatory mediators. Exogenous Nef was taken up by Caco-2 cells, increased intestinal epithelial permeability and upset the IFN-?-induced reduction of transepitelial resistance, interfering with tight junction protein expression. Moreover, Nef inhibited IFN-?-induced apoptosis and up-regulated TNF-?, IL-6 and MIP-3? production by Caco-2 cells while down-regulated IL-10 production. The simultaneous exposure of Caco-2 cells to Nef and IFN-? did not affect cytokine secretion respect to untreated cells. Finally, we found that Nef counteracted the IFN-? induced arachidonic acid cascade. Conclusion/Significance Our findings suggest that exogenous Nef, perturbing the IFN-?-induced impairment of intestinal epithelial cells, could prolong cell survival, thus allowing for accumulation of viral particles. Our results may improve the understanding of AIDS pathogenesis, supporting the discovery of new therapeutic interventions.

Quaranta, Maria Giovanna; Vincentini, Olimpia; Felli, Cristina; Spadaro, Francesca; Silano, Marco; Moricoli, Diego; Giordani, Luciana; Viora, Marina

2011-01-01

184

Initiation of an Inflammatory Response in Resident Intestinal Lamina Propria Cells -Use of a Human Organ Culture Model  

Science.gov (United States)

Resident human lamina propria immune cells serve as powerful effectors in host defense. Molecular events associated with the initiation of an intestinal inflammatory response in these cells are largely unknown. Here, we aimed to characterize phenotypic and functional changes induced in these cells at the onset of intestinal inflammation using a human intestinal organ culture model. In this model, healthy human colonic mucosa was depleted of epithelial cells by EDTA treatment. Following loss of the epithelial layer, expression of the inflammatory mediators IL1B, IL6, IL8, IL23A, TNFA, CXCL2, and the surface receptors CD14, TLR2, CD86, CD54 was rapidly induced in resident lamina propria cells in situ as determined by qRT-PCR and immunohistology. Gene microarray analysis of lamina propria cells obtained by laser-capture microdissection provided an overview of global changes in gene expression occurring during the initiation of an intestinal inflammatory response in these cells. Bioinformatic analysis gave insight into signalling pathways mediating this inflammatory response. Furthermore, comparison with published microarray datasets of inflamed mucosa in vivo (ulcerative colitis) revealed a significant overlap of differentially regulated genes underlining the in vivo relevance of the organ culture model. Furthermore, genes never been previously associated with intestinal inflammation were identified using this model. The organ culture model characterized may be useful to study molecular mechanisms underlying the initiation of an intestinal inflammatory response in normal mucosa as well as potential alterations of this response in inflammatory bowel disease.

Schroder-Braunstein, Jutta; Gras, Judith; Brors, Benedikt; Schwarz, Sonja; Szikszai, Timea; Lasitschka, Felix; Wabnitz, Guido; Heidtmann, Antje; Lee, Young-Seon; Schiessling, Serin; Leowardi, Christine; Al-Saeedi, Mohammed; Ulrich, Alexis; Engelke, Antonia; Winter, Johannes; Samstag, Yvonne; Giese, Thomas; Meuer, Stefan

2014-01-01

185

Intestinal parasite co-infection among pulmonary tuberculosis cases without human immunodeficiency virus infection in a rural county in China.  

Science.gov (United States)

Epidemiologic studies of co-infection with tuberculosis (TB) and intestinal parasites in humans have not been extensively investigated in China. A cross-section study was conducted in a rural county of Henan Province, China. Pulmonary TB (PTB) case-patients receiving treatment for infection with Mycobacterium tuberculosis and healthy controls matched for geographic area, age, and sex were surveyed by using questionnaires. Fecal and blood specimens were collected for detection of intestinal parasites, routine blood examination, and infection with human immunodeficiency virus. The chi-square test was used for univariate analysis and multivariate logistic regression models were used to adjust for potential confounding factors. A total of 369 persons with PTB and 366 healthy controls were included; all participants were negative for human immunodeficiency virus. The overall prevalence of intestinal parasites in persons with PTB was 14.9%, including intestinal protozoa (7.9%) and helminthes (7.6%). The infection spectrum of intestinal parasites was Entamoeba spp. (1.4%), Blastocystis hominis (6.2%), Trichomonas hominis (0.3%), Clonorchis sinensis (0.3%), Ascaris lumbricoides (0.5%), Trichuris trichiura (2.2%), and hookworm (4.6%). The prevalence of intestinal parasites showed no significant difference between persons with PTB and healthy controls after adjusting for potential confounding factors. There was no factor that affected infection rates for intestinal parasites between the two groups. Infection with intestinal parasites of persons with PTB was associated with female sex (adjusted odds ratio [AOR] = 2.05, 95% confidence interval [CI] = 1.01-4.17), body mass index ? 19 (AOR = 3.02, 95% CI = 1.47-6.20), and anemia (AOR = 2.43, 95% CI = 1.17-5.03). Infection of healthy controls was only associated with an annual labor time in farmlands > 2 months (AOR = 4.50, 95% CI = 2.03-10.00). In addition, there was no significant trend between rates of infection with intestinal parasites and duration of receiving treatment for infection with M. tuberculosis in persons with PTB. The prevalence of intestinal parasites was not higher in persons with PTB, and there was no evidence that PTB increased susceptibility to intestinal parasites in this study. However, for patients with PTB, women and patients with comorbidities were more likely to be infected with intestinal parasites. PMID:24166044

Li, Xin-Xu; Chen, Jia-Xu; Wang, Li-Xia; Tian, Li-Guang; Zhang, Yu-Ping; Dong, Shuang-Pin; Hu, Xue-Guang; Liu, Jian; Wang, Feng-Feng; Wang, Yue; Yin, Xiao-Mei; He, Li-Jun; Yan, Qiu-Ye; Zhang, Hong-Wei; Xu, Bian-Li; Zhou, Xiao-Nong

2014-01-01

186

Stability of Cephalosporin Prodrug Esters in Human Intestinal Juice: Implications for Oral Bioavailability  

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The levels of degradation of cefetamet pivoxil (CAT), cefuroxime axetil (CAE), and cefpodoxime proxetil (CPD) in 0.6 M phosphate buffer (pH 7.4) and human intestinal juice (pH 7.4) at 37°C over 24 h were compared. Significant differences in the time courses of degradation and in the patterns of degradation products were observed. (i) The relative proportions of the ?2- and ?3-cephalosporins were roughly reversed in the two incubation media. In phosphate buffer, the major degradation produc...

Stoeckel, Klaus; Hofheinz, Werner; Laneury, Jean Paul; Duchene, Patrick; Shedlofsky, Steve; Blouin, Robert A.

1998-01-01

187

Akkermansia muciniphila gen. nov., sp. nov., a human intestinal mucin-degrading bacterium  

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The diversity of mucin-degrading bacteria in the human intestine was investigated by combining culture and 16S rRNA-dependent approaches. A dominant bacterium, strain MucT, was isolated by dilution to extinction of faeces in anaerobic medium containing gastric mucin as the sole carbon and nitrogen source. A pure culture was obtained using the anaerobic soft agar technique. Strain MucT was a Gram-negative, strictly anaerobic, non-motile, non-spore-forming, oval-shaped bacterium that could grow...

Derrien, M. M. N.; Vaughan, E. E.; Plugge, C. M.; Vos, W. M.

2004-01-01

188

Transport and epithelial secretion of the cardiac glycoside, digoxin, by human intestinal epithelial (Caco-2) cells.  

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1. Human intestinal epithelial Caco-2 cells have been used to investigate the transepithelial permeation of the cardiac glycoside, digoxin. 2. Transepithelial basal to apical [3H]-digoxin flux exceeds apical to basal flux, a net secretion of [3H]-digoxin being observed. At 200 microM digoxin, net secretory flux (Jnet) was 10.8 +/- 0.6 nmol cm-2 h-1. Maximal secretory flux (Jmax) of vinblastine was 1.3 +/- 0.1 nmol cm-2 h-1. Cellular uptake of digoxin was different across apical and basal cell...

1996-01-01

189

Butyrate stimulates IL-32? expression in human intestinal epithelial cell lines  

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AIM: To investigate the effects of butyrate on interleukin (IL)-32? expression in epithelial cell lines.METHODS: The human intestinal epithelial cell lines HT-29, SW480, and T84 were used. Intracellular IL-32? was determined by Western blotting analyses. IL-32? mRNA expression was analyzed by real-time polymerase chain reaction.RESULTS: Acetate and propionate had no effects on IL-32? mRNA expression. Butyrate significantly enhanced IL-32? expression in all cell lines. Butyrate also up-re...

2010-01-01

190

Structural characterization of BVU_3255, a methyltransferase from human intestine antibiotic resistant pathogen Bacteroides vulgatus.  

Science.gov (United States)

Methylation is important for various cellular activities. To date, there is no report of any methyltransferase structure from the human intestine antibiotic resistant pathogen Bacteroides vulgatus. The protein BVU_3255 from B. vulgatus ATCC 8482 belongs to a SAM-dependent methyltransferase. Here, we report the crystal structure of apo BVU_3255, and its complexes with SAM and SAH, which revealed a typical class I Rossmann Fold Methyltransferase. Isothermal titration calorimetric studies showed that both SAM and SAH bind with equal affinity. The structural and sequence analysis suggested that BVU_3255 is a small molecule methyltransferase and involved in methylating the intermediates in ubiquinone biosynthesis pathway. PMID:21872662

Kumar, Veerendra; Sivaraman, J

2011-12-01

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Spatial heterogeneity and co-occurrence patterns of human mucosal-associated intestinal microbiota.  

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Human gut microbiota shows high inter-subject variations, but the actual spatial distribution and co-occurrence patterns of gut mucosa microbiota that occur within a healthy human instestinal tract remain poorly understood. In this study, we illustrated a model of this mucosa bacterial communities' biogeography, based on the largest data set so far, obtained via 454-pyrosequencing of bacterial 16S rDNAs associated with 77 matched biopsy tissue samples taken from terminal ileum, ileocecal valve, ascending colon, transverse colon, descending colon, sigmoid colon and rectum of 11 healthy adult subjects. Borrowing from macro-ecology, we used both Taylor's power law analysis and phylogeny-based beta-diversity metrics to uncover a highly heterogeneous distribution pattern of mucosa microbial inhabitants along the length of the intestinal tract. We then developed a spatial dispersion model with an R-squared value greater than 0.950 to map out the gut mucosa-associated flora's non-linear spatial distribution pattern for 51.60% of the 188 most abundant gut bacterial species. Furthermore, spatial co-occurring network analysis of mucosa microbial inhabitants together with occupancy (that is habitat generalists, specialists and opportunist) analyses implies that ecological relationships (both oppositional and symbiotic) between mucosa microbial inhabitants may be important contributors to the observed spatial heterogeneity of mucosa microbiota along the human intestine and may even potentially be associated with mutual cooperation within and functional stability of the gut ecosystem. PMID:24132077

Zhang, Zhigang; Geng, Jiawei; Tang, Xiaodan; Fan, Hong; Xu, Jinchao; Wen, Xiujun; Ma, Zhanshan Sam; Shi, Peng

2014-04-01

192

Transepithelial transport of ambroxol hydrochloride across human intestinal Caco-2 cell monolayers.  

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This study aimed i) to characterize the transepithelial transport of the mucolytic agent ambroxol hydrochloride across the intestinal barrier, ii) to classify the ambroxol according to Biopharmaceutics Classification System (BCS) and iii) to predict ambroxol absorption in humans. Transport of ambroxol (100, 300 and 1000 micromol/l) was studied in a human colon carcinoma cell line Caco-2 in apical to basolateral and basolateral to apical direction, under iso-pH 7.4 and pH-gradient (6 vs. 7.4) conditions. The relative contribution of the paracellular route was estimated using Ca2+-free transport medium. Ambroxol samples from receiver compartments were analysed by HPLC with UV detection (242 nm). Results showed that ambroxol transport is linear with time, pH-dependent and direction-independent, displays non-saturable (first-order) kinetics. Thus, the transport seems to be transcellular mediated by passive diffusion. Estimated high solubility and high permeability (P(app) = 45 x 10(-6) cm/s) of ambroxol rank it among well absorbed compounds and class I of BCS. It can be expected that the oral dose fraction of ambroxol absorbed in human intestine is high. PMID:20037197

Stetinová, Vera; Smetanová, Libuse; Kholová, Dagmar; Svoboda, Zbynek; Kvetina, Jaroslav

2009-09-01

193

Intestinal transit in healthy southern Indian subjects and in patients with tropical sprue.  

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Whole gut transit was measured in a group of 21 healthy volunteers and 21 patients with tropical sprue by radio-opaque marker technique, using mean transit time single (MTTS) and single stool transit (SST) method. Mean SST in controls was 25.8 (1.4) (SE) hours, which is considerably shorter than in controls in temperate zones. Mean SST (23.7 (0.6) h) correlated significantly with average MTTS (24.9 (1.6) h) (r = 0.88; p less than 0.001) confirming that SST is a valid method to measure intesti...

Jayanthi, V.; Chacko, A.; Gani, I. K.; Mathan, V. I.

1989-01-01

194

Modulation of stemness in a human normal intestinal epithelial crypt cell line by activation of the WNT signaling pathway.  

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The small intestine consists of two histological compartments composed of the crypts and the villi. The function of the adult small intestinal epithelium is mediated by four different types of mature cells: enterocytes, goblet, enteroendocrine and Paneth. Undifferentiated cells reside in the crypts and produce these four types of mature cells. The niche-related Wnt and Bmp signaling pathways have been suggested to be involved in the regulation and maintenance of the stem cell microenvironment. In our laboratory, we isolated the first normal human intestinal epithelial crypt (HIEC) cell model from the human fetal intestine and in this study we investigated the expression of a panel of intestinal stem cell markers in HIEC cells under normal culture parameters as well as under conditions that mimic the stem cell microenvironment. The results showed that short term stimulation of HIEC cells with R-spondin 1 and Wnt-3a±SB-216763, a glycogen synthase kinase 3? (GSK3?) inhibitor, induced ?-catenin/TCF activity and expression of the WNT target genes, cyclin D2 and LGR5. Treatment of HIEC cells with noggin, an antagonist of BMP signaling, abolished SMAD2/5/8 phosphorylation. Inducing a switch from inactive WNT/active BMP toward active WNT/inactive BMP pathways was sufficient to trigger a robust intestinal primordial stem-like cell signature with predominant LGR5, PHLDA1, PROM1, SMOC2 and OLFM4 expression. These findings demonstrate that even fully established cultures of intestinal cells can be prompted toward a CBC stem cell-like phenotype. This model should be useful for studying the regulation of human intestinal stem cell self-renewal and differentiation. PMID:24534551

Guezguez, Amel; Paré, Fréderic; Benoit, Yannick D; Basora, Nuria; Beaulieu, Jean-François

2014-04-01

195

Intestinal transit, deoxycholic acid and the cholesterol saturation of bile--three inter-related factors.  

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There is considerable evidence that the level of deoxycholic acid in the bile influences biliary cholesterol saturation. Deoxycholic acid is formed in the colon and absorbed slowly. Hence changes in colonic transit rate might influence biliary deoxycholic acid and the cholesterol saturation of bile. When 14 constipated subjects took standardised senna tablets for six weeks in a dose sufficient to lower mean whole gut transit time from 134 to 54 hours, deoxycholic acid as a proportion of bilia...

1986-01-01

196

Sugars Increase Non-Heme Iron Bioavailability in Human Epithelial Intestinal and Liver Cells  

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Previous studies have suggested that sugars enhance iron bioavailability, possibly through either chelation or altering the oxidation state of the metal, however, results have been inconclusive. Sugar intake in the last 20 years has increased dramatically, and iron status disorders are significant public health problems worldwide; therefore understanding the nutritional implications of iron-sugar interactions is particularly relevant. In this study we measured the effects of sugars on non-heme iron bioavailability in human intestinal Caco-2 cells and HepG2 hepatoma cells using ferritin formation as a surrogate marker for iron uptake. The effect of sugars on iron oxidation state was examined by measuring ferrous iron formation in different sugar-iron solutions with a ferrozine-based assay. Fructose significantly increased iron-induced ferritin formation in both Caco-2 and HepG2 cells. In addition, high-fructose corn syrup (HFCS-55) increased Caco-2 cell iron-induced ferritin; these effects were negated by the addition of either tannic acid or phytic acid. Fructose combined with FeCl3 increased ferrozine-chelatable ferrous iron levels by approximately 300%. In conclusion, fructose increases iron bioavailability in human intestinal Caco-2 and HepG2 cells. Given the large amount of simple and rapidly digestible sugars in the modern diet their effects on iron bioavailability may have important patho-physiological consequences. Further studies are warranted to characterize these interactions.

Christides, Tatiana; Sharp, Paul

2013-01-01

197

Cockroaches as carriers of human intestinal parasites in two localities in Ethiopia.  

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A study was undertaken to assess the role of cockroaches as potential carriers of human intestinal parasites in Addis Ababa and Ziway, Ethiopia. A total of 6480 cockroaches were trapped from the two localities from October 2006 to March 2007. All the cockroaches trapped in Addis Ababa (n=2240) and almost 50% (2100/4240) of those trapped in Ziway were identified as Blattella germanica. The rest of the cockroaches trapped in Ziway were identified as Periplaneta brunnea (24.52%), Pycnoscelus surinamensis (16.03%) and Supella longipalpa (9.90%). Microscopic examination of the external body washes of pooled cockroaches and individual gut contents revealed that cockroaches are carriers of Entamoeba coli and Entamoeba histolytica/dispar cysts as well as Enterobius vermicularis, Trichuris trichiura, Taenia spp. and Ascaris lumbricoides ova. Besides their role as a nuisance, the present study further confirms that cockroaches serve as carriers of human intestinal parasites. The possible association of cockroaches with allergic conditions such as asthma is also discussed. Hence, appropriate control measures should be taken particularly to make hotels and residential areas free of cockroaches as they represent a health risk. PMID:18579170

Kinfu, Addisu; Erko, Berhanu

2008-11-01

198

Engineered nanoparticles induced brush border disruption in a human model of the intestinal epithelium.  

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Nanoparticles hold great promise in cell biology and medicine due to the inherent physico-chemical properties when these materials are synthesized on the nanoscale. Moreover, their small size, and the ability to functionalize the outer nanoparticle surface makes them an ideal vector suited to traverse a number of physical barriers in the human body. While nanoparticles hold great promise for applications in cell biology and medicine, their downfall is the toxicity that accompanies exposure to biological systems. This chapter focuses on exposure via the oral route since nanomaterials are being engineered to act as carriers for drugs, contrast agents for specialized imaging techniques, as well as ingested pigments approved by regulatory agencies for human food products. After these nanomaterials are ingested they have the potential to interact with a number of biologically significant tissues, one of which is the epithelium of the small intestine. Within the small intestine exists enterocytes whose principal function is nutrient absorption. The absorptive process is aided by microvilli that act to increase the surface area of the epithelium. Dense arrays of microvilli, referred to as the brush border, have recently been shown to undergo disruption as a consequence of exposure to nanomaterials. This chapter aims to set the stage for detailed mechanistic studies at the cell biology level concerning this newly emerging nanotoxicity research paradigm, as the underlying structural characterization responsible for the existence of microvilli have been elucidated. PMID:24683027

Faust, James J; Masserano, Benjamin M; Mielke, Adam H; Abraham, Anup; Capco, David G

2014-01-01

199

Effect of c-kit ligand, stem cell factor, on mediator release by human intestinal mast cells isolated from patients with inflammatory bowel disease and controls.  

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The regulation of mediator release in human intestinal mast cells is largely unknown. Apart from IgE receptor crosslinking no secretagogues have been described so far. This study examined the effect of two cytokines (c-kit ligand and interleukin 3) and other agonists on human intestinal mast cell function. Cells were isolated from surgery specimens of 47 patients undergoing intestinal resection because of tumours or inflammatory bowel disease. Cell suspensions contained 3.6% mast cells (mean ...

Bischoff, S. C.; Schwengberg, S.; Wordelmann, K.; Weimann, A.; Raab, R.; Manns, M. P.

1996-01-01

200

Isolation and Identification of Intestinal CYP3A Inhibitors from Cranberry (Vaccinium macrocarpon) using Human Intestinal Microsomes  

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Cranberry juice is used routinely, especially among women and the elderly, to prevent and treat urinary tract infections. These individuals are likely to be taking medications concomitantly with cranberry juice, leading to concern about potential drug-dietary substance interactions, particularly in the intestine, which, along with the liver, is rich in expression of the prominent drug metabolizing enzyme, cytochrome P450 3A (CYP3A). Using a systematic in vitro-in vivo approach, a cranberry ju...

Kim, Eunkyung; Sy-cordero, Arlene; Graf, Tyler N.; Brantley, Scott J.; Paine, Mary F.; Oberlies, Nicholas H.

2011-01-01

 
 
 
 
201

Similar uptake profiles of microcystin-LR and -RR in an in vitro human intestinal model  

International Nuclear Information System (INIS)

Highlights: ? First description of in vitro cellular uptake of MCs into intestinal cells. ? OATP 3A1 and OATP 4A1 are expressed in Caco-2 cell membranes. ? MC-LR and MC-RR show similar uptake in Caco-2 cells. ? MCs are probably excreted from Caco-2 cells by an active mechanism. -- Abstract: Microcystins (MCs) are cyclic hepatotoxins produced by various species of cyanobacteria. Their structure includes two variable amino acids (AA) leading to more than 80 MC variants. In this study, we focused on the most common variant, microcystin-LR (MC-LR), and microcystin-RR (MC-RR), a variant differing by only one AA. Despite their structural similarity, MC-LR elicits higher liver toxicity than MC-RR partly due to a discrepancy in their uptake by hepatic organic anion transporters (OATP 1B1 and 1B3). However, even though ingestion is the major pathway of human exposure to MCs, intestinal absorption of MCs has been poorly addressed. Consequently, we investigated the cellular uptake of the two MC variants in the human intestinal cell line Caco-2 by immunolocalization using an anti-MC antibody. Caco-2 cells were treated for 30 min to 24 h with several concentrations (1-50 ?M) of both variants. We first confirmed the localization of OATP 3A1 and 4A1 at the cell membrane of Caco-2 cells. Our study also revealed a rapid uptake of both variants in less than 1 h. The uptake profiles of the two variants did not differ in our immunostaining study neither with respect to concentration nor the time of exposure. Furthermore, we have demonstrated for the first time the nuclear localization of MC-RR and confirmed that of MC-LR. Finally, our results suggest a facilitated uptake and an active excretion of MC-LR and MC-RR in Caco-2 cells. Further investigation on the role of OATP 3A1 and 4A1 in MC uptake should be useful to clarify the mechanism of intestinal absorption of MCs and contribute in risk assessment of cyanotoxin exposure.

2011-11-28

202

Mapping of liver-enriched transcription factors in the human intestine  

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Full Text Available AIM: To investigate the gene expression pattern of hepatocyte nuclear factor 6 (HNF6 and other liver-enriched transcription factors in various segments of the human intestine to better understand the differentiation of the gut epithelium.METHODS: Samples of healthy duodenum and jejunum were obtained from patients with pancreatic cancer whereas ileum and colon was obtained from patients undergoing right or left hemicolectomy or (rectosigmoid or rectal resection. All surgical specimens were subjected to histopathology. Excised tissue was shock-frozen and analyzed for gene expression of liver-enriched transcription factors by semiquantitative reverse transcription polymerase chain and compared to the human colon carcinoma cell line Caco-2. Protein expression of major liver-enriched transcription factors was determined by Western blotting while the DNA binding of HNF6 was investigated by electromobility shift assays.RESULTS: The gene expression patterning of liver-enriched transcription factors differed in the various segments of the human intestine with HNF6 gene expression being most abundant in the duodenum (P < 0.05 whereas expression of the zinc finger protein GATA4 and of the HNF6 target gene ALDH3A1 was most abundant in the jejunum (P < 0.05. Likewise, expression of FOXA2 and the splice variants 2 and 4 of HNF4? were most abundantly expressed in the jejunum (P < 0.05. Essentially, expression of transcription factors declined from the duodenum towards the colon with the most abundant expression in the jejunum and less in the ileum. The expression of HNF6 and of genes targeted by this factor, i.e. neurogenin 3 (NGN3 was most abundant in the jejunum followed by the ileum and the colon while DNA binding activity of HNF4? and of NGN3 was confirmed by electromobility shift assays to an optimized probe. Furthermore, Western blotting provided evidence of the expression of several liver-enriched transcription factors in cultures of colon epithelial cells, albeit at different levels.CONCLUSION: We describe significant local and segmental differences in the expression of liver-enriched transcription factors in the human intestine which impact epithelial cell biology of the gut.

Frank Lehner, Ulf Kulik, Juergen Klempnauer,Juergen Borlak

2010-08-01

203

Utilização do método videolaparoscopico na reconstituição do trânsito intestinal após a operação de Hartmann / The use of videolaparoscopic approach in the intestinal transit restoration after Hartmann's procedure  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo é apresentar a padronização da técnica operatória e os resultados obtidos com a utilização do acesso videolaparoscópico na reconstituição do trânsito intestinal em pacientes previamente submetidos à operação de Hartmann por causas diversas. Foram analisados prospectivamente 32 pacientes, [...] no período de dezembro de 1991 a junho de 1997, com distribuição semelhante com relação ao sexo e com idade média de 42,4 anos. Todos os pacientes foram submetidos ao mesmo preparo pré-operatório e à mesma técnica cirúrgica. Ocorreram três (9,3%) complicações transoperatórias. Uma (3,1 %) anastomose mecânica incompleta, necessitando de endossutura manual, uma (3,1 %) laceração do reto com o grampeador mecânico e uma (3,1 %) lesão da artéria epigástrica direita. Ocorreram ainda três (9,3%) conversões, sendo uma (3,1 %) devido à laceração do reto com o grampeador mecânico, outra (3.1 %) pela invasão tumoral na pelve e outra (3,1 %) pela presença de excessivas aderências intraperitoneais. O tempo operatório variou de 30 a 240 minutos, na média de 126,2 minutos (2,1 horas). A evolução clínica pós-operatória foi satisfatória. Nove (31,0%) pacientes não referiram dor, enquanto 13 (44,8%) a referiram em pequena intensidade, e apenas sete (24,0%) queixaram-se de dor com maior intensidade. A dieta líquida via oral foi instituída no período médio de 1,6 dias, e a primeira evacuação ocorreu na média de 3,2 dias de pós-operatório. O período médio de hospitalização foi de 4,7 dias. Ocorreram complicações pós-operatórias em oito (27,5%) pacientes. Duas (6,8%) infecções da ferida do estoma, dois pacientes (6,8%) com dor no ombro direito, uma (3,4%) deiscência de anastomose, um (3,4%) caso de peritonite por provável contaminação do material cirúrgico, uma coleção líquida pélvica e uma hérnia incisional. Em conclusão, a reconstituição do trânsito intestinal por videolaparoscopia apresentou-se segura e eficaz, podendo constituir-se no método cirúrgico de escolha, pois foi utilizada com sucesso em 90,6% dos pacientes. Abstract in english We present the operative technique and the results of the laparoscopic approach for Hartmann's colostomy reversal. Thirty two patients were prospectively analysed from december 1991 to june 1997. They presented a similar incidence regarding sex distribution, and a median age of 42.4 years old. Ali p [...] atients underwent the same preoperative preparation and operative technique. Three (9.3%) intraoperative complications were observed: an uncompleted anastomosis (3.1%), requiring an endosuture, a rectal perforation by the mechanical stapler and a right epigastric artery lesion. There were convertion to open surgery in three (9.3%) patients: one (3.1%) due to rectal perforation by the mechanical staple1; one (3.1%) for tumoral pelvic invasion and another because of excessive intra-peritoneal adhesions. Operative time varied from 30 to 240 minutes, with a mean time of 126;2 minutes. Nine (31.0%) patients didn't present pain, while 13 (44.8%) referred minimal pain and seven (24.0%) complained severe pain. Oral liquid diet intake occurred within a mean time of 1.6 days and the first evacuation observed after a mean 3.2 postoperative days. Mean hospitalization time was 4.7 days. Postoperative complications occurred in eight (27.5%) patients. Two (6.8%) stoma wound infections, right shoulder pain in two (6.8%) patients, one (3.4%) anastomotic dehiscence, one peritonitis probably due to contaminationfrom surgical instruments, a liquid pelvic coliection and an incisional haernia. 1n conclusion, videolaparoscopic restoration of the intestinal transit demonstrated to be safe and effective. It could be the method of choice because of its success in 90.6 per cent of the patients.

Regadas, Francisco Sérgio P.; Regadas, Sthela M. Murad; Rodrigues, Lusmar Veras.

204

Inhibition of inflammatory mediators by polyphenolic plant extracts in human intestinal Caco-2 cells.  

Science.gov (United States)

The mitogen-activated protein kinases (MAPK) and nuclear factor kappaB (NF-kappaB) are involved in transduction cascades that play a key role in inflammatory response. We tested the ability of preselected natural polyphenolic extracts (grape seed, cocoa, sugar cane, oak, mangosteen and pomegranate) to modulate intestinal inflammation using human intestinal Caco-2 cells treated for 4h with these extracts and then stimulated by cytokines for 24 or 48h. The effect of polyphenolic extracts, at 50 micromol of gallic acid equivalent/l, was investigated on inflammation-related cellular events: (i) NF-kappaB activity (cells transfected with a NF-kappaB-luciferase construct), (ii) activation of Erk1/2 and JNK (western blotting), (iii) secretion of interleukin 8 (IL-8) (ELISA), (iv) secretion of prostaglandin (PG) E(2) (ELISA), (v) production of NO (Griess method). Results show that: (i) sugar cane, oak and pomegranate extracts inhibited NF-kappaB activity (from 1.6 to 1.9-fold) (P<0.001); (ii) pomegranate slightly inhibited Erk1/2 activation (1.3-fold) (P=0.008); (iii) oak and pomegranate decreased NO synthesis by 1.5-fold (P<0.001) and that of IL-8 by 10.3 and 6.7-fold respectively; (iv) pomegranate and cocoa decreased PGE(2) synthesis by 4.6 (P<0.0001) and 2.2-fold (P=0.001), respectively. We suggest that pomegranate extract could be particularly promising in dietary prevention of intestinal inflammation. PMID:19233242

Romier-Crouzet, Béatrice; Van De Walle, Jacqueline; During, Alexandrine; Joly, Aurélie; Rousseau, Charline; Henry, Olivier; Larondelle, Yvan; Schneider, Yves-Jacques

2009-06-01

205

Human intestinal parasites in the past: new findings and a review  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Almost all known human specific parasites have been found in ancient feces. A review of the paleoparasitological helminth and intestinal protozoa findings available in the literature is presented. We also report the new paleoparasitologic findings from the examination performed in samples collected [...] in New and Old World archaeological sites. New finds of ancylostomid, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Trichostrongylus spp., Diphyllobothrium latum, Hymenolepis nana and Acantocephalan eggs are reported. According to the findings, it is probable that A. lumbricoides was originally a human parasite. Human ancylostomids, A. lumbricoides and T. trichiura, found in the New World in pre-Columbian times, have not been introduced into the Americas by land via Beringia. These parasites could not supported the cold climate of the region. Nomadic prehistoric humans that have crossed the Bering Land Bridge from Asia to the Americas in the last glaciation, probably during generations, would have lost these parasites, which life cycles need warm temperatures in the soil to be transmitted from host to host. Alternative routes are discussed for human parasite introduction into the Americas.

Gonçalves, Marcelo Luiz Carvalho; Araújo, Adauto; Ferreira, Luiz Fernando.

206

Vitamin A metabolism in the human intestinal Caco-2 cell line  

International Nuclear Information System (INIS)

The human intestinal Caco-2 cell line, described as enterocyte-like in a number of studies, was examined for its ability to carry out the metabolism of vitamin A normally required in the absorptive process. Caco-2 cells contained cellular retinol-binding protein II, a protein which is abundant in human villus-associated enterocytes and may play an important role in the absorption of vitamin A. Microsomal preparations from Caco-2 cells contained retinal reductase, acyl-CoA-retinol acyltransferase (ARAT), and lecithin-retinol acyltransferase (LRAT) activites, which have previously been proposed to be involved in the metabolism of dietary vitamin A in the enterocyte. When intact Caco-2 cells were provided with ?-carotene, retinyl acetate, or retinyl acetate, or retinol, synthesis of retinyl palmitoleate, oleate, palmitate, and small amounts of stearate resulted. However, exogenous retinyl palmitate or stearate was not used by Caco-2 cells as a source of retinol for ester synthesis. While there was a disproportionate synthesis of monoenoic fatty acid esters of retinol in Caco-2 cells compared to the retinyl esters typically found in human chylomicrons or the esters normally synthesized in rat intestine, the pattern was consistent with the substantial amount of unsaturated fatty acids, particularly 18:1 and 16:1, found in the sn-1 position of Caco-2 microsomal phosphatidylcholine, the fatty acyl donor for LRAT. Both ARAT and LRAT have been proposed to be responsible for retinyl ester synthesis in the enterocyte. These data suggest the LRAT may be the physiologically important enzyme for the esterification of retinol in Caco-2 cells

1990-01-01

207

SREBP-2 negatively regulates FXR-dependent transcription of FGF19 in human intestinal cells.  

Science.gov (United States)

Sterol regulatory element-binding protein-2 (SREBP-2) is a basic helix-loop-helix-leucine zipper transcription factor that positively regulates transcription of target genes involved in cholesterol metabolism. In the present study, we have investigated a possible involvement of SREBP-2 in human intestinal expression of fibroblast growth factor (FGF)19, which is an endocrine hormone involved in the regulation of lipid and glucose metabolism. Overexpression of constitutively active SREBP-2 decreased FGF19 mRNA levels in human colon-derived LS174T cells. In reporter assays, active SREBP-2 overexpression suppressed GW4064/FXR-mediated increase in reporter activities in regions containing the IR-1 motif (+848 to +5200) in the FGF19 gene. The suppressive effect disappeared in reporter activities in the region containing the IR-1 motif when the mutation was introduced into the IR-1 motif. In electrophoretic mobility shift assays, binding of the FXR/retinoid X receptor ? heterodimer to the IR-1 motif was attenuated by adding active SREBP-2, but SREBP-2 binding to the IR-1 motif was not observed. In chromatin immunoprecipitation assays, specific binding of FXR to the IR-1-containing region of the FGF19 gene (+3214 to +3404) was increased in LS174T cells by treatment with cholesterol and 25-hydroxycholesterol. Specific binding of SREBP-2 to FXR was observed in glutathione-S-transferase (GST) pull-down assays. These results suggest that SREBP-2 negatively regulates the FXR-mediated transcriptional activation of the FGF19 gene in human intestinal cells. PMID:24321096

Miyata, Masaaki; Hata, Tatsuya; Yamazoe, Yasushi; Yoshinari, Kouichi

2014-01-10

208

Perfil epidemiológico e morbimortalidade dos pacientes submetidos à reconstrução de trânsito intestinal: experiência de um centro secundário do nordeste Brasileiro Epidemiologic profile and morbimortality of patients undergoing to intestinal transit reconstruction: experience of a secundary health service in Brazil northeast  

Directory of Open Access Journals (Sweden)

Full Text Available Racional- A reconstrução do trânsito intestinal não está isenta de riscos cirúrgicos e apresenta taxas consideráveis de complicações pós-operatórias, sendo que a infecção continua a ser um dos maiores desafios existentes neste procedimento. Métodos- Foram analisados retrospectivamente 86 prontuários de pacientes com colostomia ou ileostomia, através de fatores que tivessem impacto sobre a morbimortalidade após a reconstrução de trânsito intestinal, de janeiro de 2003 a abril de 2009. Resultados- Houve 20 mulheres e 60 homens, com idade média de 43 anos. A colostomia em alça (n: 34 e o trauma abdominal indicando colostomia ou ileostomia foram as condições mais frequentes. O intervalo médio entre a confecção do estoma e a reconstrução de trânsito intestinal foi 15,7 meses. O índice de morbidade foi 56,8%, sendo a infecção incisional a complicação mais comum (27.47%. A permanência hospitalar média foi 7,6 dias. Houve regressão linear positiva entre permanência hospitalar pós-operatória e a idade do paciente. Demonstrou-se associação estatisticamente significativa entre o prolongamento da permanência hospitalar e a ocorrência de complicações (pBackground - The reconstruction of the intestinal tract is not surgical complications risk-free and is associated to postoperative complications high rates; furthermore, infection remains the hardest challenge in this procedure. Methods - Retrospectively, eighty-six patients with intestinal stomas were analyzed through factors that impact on the morbimortality afterwards intestinal transit reconstruction, since January 2003 to April 2009. Results - Loop colostomy (n=34 and abdominal trauma implicating 38.2% of indications to colostomy or ileostomy were the most frequent conditions. The mean interval between stoma confection and intestinal transit reconstruction was 15.7 months. The morbidity frequency was 56.8% and incisional infection was its commonest complication (27.47%. The mean inpatient length of stay was 7.6 days. There was positive linear regression between post-operative inpatient length of stay and inpatient's age. Inpatient length of stay prolongation is associated to occurrence of complications (p<0,001. Conclusion - Post-operative complications and age are associated to inpatient length of stay prolongation.

Jeany Borges e Silva

2010-09-01

209

Shigella flexneri strains produce bacteriocins active against members of the human microbial intestinal flora.  

Science.gov (United States)

The principal aim of this work was to detect the bacteriocinogenic capacity of S. flexneri strains on members of the human intestinal flora. A total of 49 bacteriocinogenic S. flexneri strains were isolated from individuals of both sexes and different ages. The bacteriocins were detected by means of the drop method using E. coli and B. fragilis as target strains. The serotypes of the S. flexneri were determined. The producer capacity of bacteriocins was analysed in 10 different colonies of the same cellular clone and also the arbitrary units were determined. The highest number of bacteriocinogenic S. flexneri strains were obtained from diarrhoeal individuals from 0-10 years old and the S. flexneri serotype 2a was the most abundant. It was demonstrated that E. coli and B. fragilis isolated from the normal intestinal flora of healthy individuals were susceptible to the bacteriocinogenic S. flexneri strains. By means of the determination of arbitrary units per ml of the bacteriocin, it was demonstrated that colonies from a single colony isolate of a same clone of bacteriocinogenic S. flexneri produce different quantities of bacteriocin. PMID:17061528

Padilla, Carlos; Lobos, Olga; Hubert, Elizabeth

2004-01-01

210

Transition State Analysis of Thymidine Hydrolysis by Human Thymidine Phosphorylase*  

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Human thymidine phosphorylase (hTP) is responsible for thymidine (dT) homeostasis and its action promotes angiogenesis. In the absence of phosphate, hTP catalyzes a slow hydrolytic depyrimidination of dT yielding thymine and 2-deoxyribose (dRib). Its transition state was characterized using multiple kinetic isotope effect (KIE) measurements. Isotopically enriched thymidines were synthesized enzymatically from glucose or (deoxy)ribose and intrinsic KIEs were used to interpret the transition st...

Schwartz, Phillip A.; Vetticatt, Mathew; Schramm, Vern L.

2010-01-01

211

Correlation between human papillomavirus infection and bladder transitional cell carcinoma  

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Abstract Background To determine the association of human papillomavirus infection (HPV) and transitional cell carcinoma (TCC). Methods Using polymerase chain reaction, fifty-nine bladder tissue specimens of patients with transitional cell carcinoma of bladder compared with 20 bladder samples of cases with non-neoplastic disorders. Results Male to female ratio was similar in the two groups (50/9 vs. 16/4, P = 0.62). Mean age was 67 ± 10.8...

Barghi MR; Hajimohammadmehdiarbab A; Smm, Moghaddam Hosseini; Kazemi B

2005-01-01

212

Epidermal growth factor upregulates serotonin transporter in human intestinal epithelial cells via transcriptional mechanisms  

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Serotonin transporter (SERT) regulates extracellular availability of serotonin and is a potential pharmacological target for gastrointestinal disorders. A decrease in SERT has been implicated in intestinal inflammatory and diarrheal disorders. However, little is known regarding regulation of SERT in the intestine. Epidermal growth factor (EGF) is known to influence intestinal electrolyte and nutrient transport processes and has protective effects on intestinal mucosa. Whether EGF regulates SE...

Gill, Ravinder K.; Anbazhagan, Arivarasu Natarajan; Esmaili, Ali; Kumar, Anoop; Nazir, Saad; Malakooti, Jaleh; Alrefai, Waddah A.; Saksena, Seema

2011-01-01

213

Digestion of the carbohydrates of banana (Musa paradisiaca sapientum) in the human small intestine.  

Science.gov (United States)

The digestion and absorption from the small bowel of the carbohydrate of banana has been studied by feeding ileostomy subjects banana from six batches of different ripeness and measuring the amounts excreted in the effluent. Starch content of bananas depended on the ripeness being 37% of dry weight in the least ripe and 3% in the most ripe. Excretion of carbohydrate from banana in ileostomy effluent ranged from 4-19 g/day and was directly related to the starch content (r = 0.99). Up to 90% of the starch could be accounted for in the effluent. Complete recovery of nonstarch polysaccharides [NSP (dietary fiber)] was obtained. The amount of banana starch not hydrolyzed and absorbed from the human small intestine and therefore passing into the colon may be up to 8 times more than the NSP present in this food and depends on the state of ripeness when the fruit is eaten. PMID:3014853

Englyst, H N; Cummings, J H

1986-07-01

214

Localization of ABCG5 and ABCG8 proteins in human liver, gall bladder and intestine  

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Full Text Available Abstract Background The molecular mechanisms that regulate the entry of dietary sterols into the body and their removal via hepatobiliary secretion are now beginning to be defined. These processes are specifically disrupted in the rare autosomal recessive disease, Sitosterolemia (MIM 210250. Mutations in either, but not both, of two genes ABCG5 or ABCG8, comprising the STSL locus, are now known to cause this disease and their protein products are proposed to function as heterodimers. Under normal circumstances cholesterol, but not non-cholesterol sterols, is preferentially absorbed from the diet. Additionally, any small amounts of non-cholesterol sterols that are absorbed are rapidly taken up by the liver and preferentially excreted into bile. Based upon the defects in sitosterolemia, ABCG5 and ABCG8 serve specifically to exclude non-cholesterol sterol entry at the intestinal level and are involved in sterol excretion at the hepatobiliary level. Methods Here we report the biochemical and immuno-localization of ABCG5 and ABCG8 in human liver, gallbladder and intestine using cell fractionation and immunohistochemical analyses. Results We raised peptide antibodies against ABCG5 and ABCG8 proteins. Using human liver samples, cell fractionation studies showed both proteins are found in membrane fractions, but they did not co-localize with caveolin-rafts, ER, Golgi or mitochondrial markers. Although their distribution in the sub-fractions was similar, they were not completely contiguous. Immunohistochemical analyses showed that while both proteins were readily detectable in the liver, ABCG5 was found predominately lining canalicular membranes, whereas ABCG8 was found in association with bile duct epithelia. At the cellular level, ABCG5 appeared to be apically expressed, whereas ABCG8 had a more diffuse expression pattern. Both ABCG5 and ABCG8 appeared to localize apically as shown by co-localization with MRP2. The distribution patterns of ABCG5 and ABCG8 in the gallbladder were very similar to each other. In the small intestine both ABCG5 and ABCG8 appear to line the brush border. However, at the level of the enterocyte, the cellular distribution patterns of ABCG5 and ABCG8 differed, such that ABCG5 was more diffuse, but ABCG8 was principally apical. Using standard deglycosylation methods, ABCG5 and ABCG8 do not appear to be glycosylated, suggesting a difference between human and mouse proteins. Conclusion We report the distribution patterns of ABCG5 and ABCG8 in human tissues. Cell fractionation studies showed that both proteins co-fractionated in general, but could also be found independent of each other. As predicted, they are expressed apically in both intestine and liver, although their intracellular expression patterns are not completely congruent. These studies support the concept of heterodimerization of ABCG5 and ABCG8, but also support the notion that these proteins may have an independent function.

Chavin Kenneth D

2004-09-01

215

Primary culture of human keratinocytes planted on pig’s intestine  

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Full Text Available Tissue engineering, in the fields of skin regeneration,seeks to overcome the limitationsassociated with the use of immediate auto-grafts,since choosing the donor region of the patientconstitutes a risk for the patient himself and isinsufficient if the injury that has to be repairedis very large. The use of the pig’s small intestinesubmucosa (SIS has being proved as a fillingbiomaterial to treat injuries, because of its specialcomposition, it lowers pain and inflammationsince its first application and it favours earlymobility to the wounded area. The present studydeveloped a protocol for the primary cultureof human keratinocytes from infant foreskins,and used small intestinal submucosa (SIS likeculture substrate. Cellular adherence potentialand proliferation capability of the keratinocytesover this substrate was evaluated.

Sandra Rocío Ramírez

2008-12-01

216

Substrate specificity and some properties of phenol sulfotransferase from human intestinal Caco-2 cells  

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The phase 2 metabolic reactions, sulfation and glucuronidation, were studied in a human colon carcinoma cell line (Caco-2), which has been developed as a model of intestinal enterocytes. Phenol sulfotransferase was isolated from Caco-2 cells cultured for 7, 14 and 21 days. The enzyme catalyzed the sulfation of both p-nitrophenol and catecholamines as well as most catecholamine metabolites. The affinity (K{sub m}) of PST for dopamine was much higher than for p-nitrophenol, and the specific activity of PST with both substrates increased with the age of the cells. The thermal stability of Caco-2 PST increased with cell age and was not dependent on the acceptor substrate used. The thermolabile PST from 7-day old cells was more sensitive to NEM than was the thermostable enzyme from 21-day old cells. No UDP-glucuronyltransferase activity was detected in 7-, 14- and 21-day old Caco-2 cells with any of the methods used.

Baranczyk-Kuzma, A.; Garren, J.A.; Hidalgo, I.J.; Borchardt, R.T. (Univ. of Kansas, Lawrence (United States))

1991-01-01

217

Intestinal parasitic infections and eosinophilia in an human immunedeficiency virus positive population in Honduras  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The occurrence of intestinal parasites, their regional distribution and their relations to eosinophilia were studied in 133 human immunodeficiency virus (HIV) positive individuals from Honduras. After signing an informed consent, participants answered a socio-demographic and risk factor questionnair [...] e, a complete physical examination, medical history, and a series of laboratory tests. All participants were HIV positive but not acquired immunodeficiency syndrome positive. Of them, 67% were co-infected with pathogen and non pathogen parasites. Overall occurrence of nematodes was: 44.3% for Trichuris trichiura, 24% for Ascaris lumbricoides, 12% for Hookworm and 7.5% for Strongyloides stercoralis. No cases of Giardia lamblia, acute amebiasis or cryptosporidiasis were diagnosed. Mean eosinophil percents for participants were consistently and significantly higher in infected than in non infected individuals: 22% for Hookworm vs 7.2% (p

Rina G, Kaminsky; Ramón J, Soto; Adriana, Campa; Marianna K, Baum.

218

Specific binding of lactoferrin to Escherichia coli isolated from human intestinal infections  

International Nuclear Information System (INIS)

The degrees of human lactoferrin (HLf) and bovine lactoferrin (BLf) binding in 169 Escherichia coli strains isolated from human intestinal infections, and in an additional 68 strains isolated from healthy individuals, were examined in a 125I-labelled protein binding assay. The binding was expressed as a percentage calculated from the total labelled ligand added to bacteria. The HLf and BLf binding to E. coli was in the range 3.7 to 73.4% and 4.8 to 61.6%, respectively. Enterotoxigenic strains demonstrated a significantly higher HLf binding (median = 19%) than enteropathogenic, enteroinvasive, enterohaemorrhagic strains or normal intestinal E. coli isolates (medians 6 to 9). Enteropathogenic strains belonging to serotypes O44 and O127 demonstrated significantly higher HLf binding compared to O26, O55, O111, O119 and O126. No significant differences in the degree of HLf or BLf binding were found between aerobactin-producing and non-producing strains. The interaction was further characterized in a high Lf-binging EPEC strain, E34663 (serotype O127). The binding was stable in the pH range 4.0 to 7.5, did not dissociate in the presence of 2M NaCl or 2M urea, and reached saturation within two h. Unlabelled HLf and BLf displaced the 125I-HLf binding to E34663 in a dose-dependent manner. Apo- and iron-saturated forms of Lf demonstrated similar binding to E34663. Among various unlabelled subephithelial matrix proteins and carbohydrates tested (in 104-fold excess) only fibronectin and fibrinogen caused a moderate inhibition of 125I-HLf binding. According to Scatchard plot analysis, 5,400 HLf-binding sites/cell, with an affinity constant (Ka) of 1.4 x 10-7 M, were estimated in strain E34663. These data establish the presence of a specific Lf-binding mechanism in E. coli. (au)

1991-01-01

219

The Influence of Different Apple Based Supplements on the Intestinal Microbiota of Humans.  

DEFF Research Database (Denmark)

Background and objective: The present project is part of the large ISAFRUIT project, where one of the objectives is to identify effects of apple and apple product on parameters related to gut health. In a previous rat study we observed changes in the intestinal microbiota of rats fed whole apples, pomace or apple pectin ([1], and we were interested in finding out if the same effect can be observed in humans. Method: The study was conducted as a randomized, controlled 5 x 28 days cross-over study with 24 healthy persons of both genders. The persons were following a pectin- and polyphenol free restriction diet during the control period, and in the four other periods it was supplied with four different apple based supplements. Between the diets there was a 2-week wash-out period still on the restriction diet. The four apple based supplements were: 1) whole apples, 2) clear apple juice (pectin-free), 3) cloudy juice (apple juice with pulp), and 4) pomace (press cake from the cloudy juice production process). Fecal samples were taken before and after each diet period. After DNA extraction, Denaturing Gradient Gel Electrophoresis (DGGE) with universal primers and specific primers for bifidobacteria and Clostridium cluster XIVa was performed. Bands differing between the periods were sequenced, and qPCR was performed to verify the changes observed by DGGE. Results: Changes in the microbiota was observed by DGGE in persons consuming whole apples and pomace. In contrast, the two juice supplements did not show any effect on the microbiota by DGGE. Conclusion: Consumption of whole apples or pomace is able to modify the intestinal microbiota of humans.

Bergström, Anders; Wilcks, Andrea

220

Absorption and transport of pachymic acid in the human intestinal cell line Caco-2 monolayers  

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Full Text Available Objective: To study the absorption and transport of pachymic acid (PA isolated from the sclerotium of Poria cocos (Schw. Wolf. in human intestinal epithelium.Methods: By using Caco-2 (the human colonic adenocarcinoma cell lines cell monolayers as an intestinal epithelial cell model, the permeability of PA was studied from apical side (AP side to basolateral side (BL side or from BL side to AP side. The PA was measured by reversed-phase high performance liquid chromatography coupled with UV detector at maximum absorption wavelength of 210 nm. Transport parameters and apparent permeability coefficients (Papp were then calculated and compared with those of propranolol and atenolol, which were the transcellular transport markers for high and poor permeability respectively.Results: The Papp values of PA were (9.50±2.20 10?7 cm/s from AP side to BL side, and (11.30±5.90 10?7 cm/s from BL side to AP side, respectively. Under the condition of this experiment, the Papp values were 1.45×10?5 cm/s for propranolol and 4.22×10?7 cm/s for atenolol.Conclusion: PA is transported through the Caco-2 cell monolayer in a concentration-dependent manner and the transport was linear with time. The absorption in apical to basolateral direction and secretion in basolateral to apical direction were poor and their Papp values were comparable to atenolol. Besides passive diffusion of PA, ATP is partially involved in its transport

Yan ZHENG

2008-07-01

 
 
 
 
221

Responses of Human Intestinal Microvascular Endothelial Cells to Shiga Toxins 1 and 2 and Pathogenesis of Hemorrhagic Colitis  

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Endothelial damage is characteristic of infection with Shiga toxin (Stx)-producing Escherichia coli (STEC). Because Stx-mediated endothelial cell damage at the site of infection may lead to the characteristic hemorrhagic colitis of STEC infection, we compared the effects of Stx1 and Stx2 on primary and transformed human intestinal microvascular endothelial cells (HIMEC) to those on macrovascular endothelial cells from human saphenous vein (HSVEC). Adhesion molecule, interleukin-8 (IL-8), and ...

Jacewicz, Mary S.; Acheson, David W. K.; Binion, David G.; West, Gail A.; Lincicome, Lisa L.; Fiocchi, Claudio; Keusch, Gerald T.

1999-01-01

222

Modulation of pathogen-induced CCL20 secretion from HT-29 human intestinal epithelial cells by commensal bacteria  

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Abstract Background Human intestinal epithelial cells (IECs) secrete the chemokine CCL20 in response to infection by various enteropathogenic bacteria or exposure to bacterial flagellin. CCL20 recruits immature dendritic cells and lymphocytes to target sites. Here we investigated IEC responses to various pathogenic and commensal bacteria as well as the modulatory effects of commensal bacteria on pathogen-induced CCL20 secretion. HT-29 human IECs were incubated with commensal ...

Sibartie Shomik; O'Hara Ann M; Ryan Jude; Fanning Áine; Mahony Jim, O.; Neill Shaun, O.; Sheil Barbara; Mahony Liam, O.; Shanahan Fergus

2009-01-01

223

Modulation of pathogen-induced CCL20 secretion from HT-29 human intestinal epithelial cells by commensal bacteria  

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BACKGROUND: Human intestinal epithelial cells (IECs) secrete the chemokine CCL20 in response to infection by various enteropathogenic bacteria or exposure to bacterial flagellin. CCL20 recruits immature dendritic cells and lymphocytes to target sites. Here we investigated IEC responses to various pathogenic and commensal bacteria as well as the modulatory effects of commensal bacteria on pathogen-induced CCL20 secretion. HT-29 human IECs were incubated with commensal bacteria (Bifidobacterium...

Sibartie, S.; O´hara, A. M.; Ryan, J.; Fanning, A.; O´mahony, J.; O´neill, S.; Sheil, B.; O´mahony, L.; Shanahan, F.

2009-01-01

224

Differential modulation of human intestinal bifidobacterium populations after consumption of a wild blueberry (Vaccinium angustifolium) drink.  

Science.gov (United States)

Bifidobacteria are gaining increasing interest as health-promoting bacteria. Nonetheless, the genus comprises several species, which can exert different effects on human host. Previous studies showed that wild blueberry drink consumption could selectively increase intestinal bifidobacteria, suggesting an important role for the polyphenols and fiber present in wild blueberries. This study evaluated the modulation of the most common and abundant bifidobacterial taxonomic groups inhabiting the human gut in the same fecal samples. The analyses carried out showed that B. adolescentis, B. breve, B. catenulatum/pseudocatelulatum, and B. longum subsp. longum were always present in the group of subjects enrolled, whereas B. bifidum and B. longum subsp. infantis were not. Furthermore, it was found that the most predominant bifidobacterial species were B. longum subsp. longum and B. adolescentis. The results obtained revealed a high interindividual variability; however, a significant increase of B. longum subsp. infantis cell concentration was observed in the feces of volunteers after the wild blueberry drink treatment. This bifidobacterial group was shown to possess immunomodulatory abilities and to relieve symptoms and promote the regression of several gastrointestinal disorders. Thus, an increased cell concentration of B. longum subsp. infantis in the human gut could be considered of potential health benefit. In conclusion, wild blueberry consumption resulted in a specific bifidogenic effect that could positively affect certain populations of bifidobacteria with demonstrated health-promoting properties. PMID:23883473

Guglielmetti, Simone; Fracassetti, Daniela; Taverniti, Valentina; Del Bo', Cristian; Vendrame, Stefano; Klimis-Zacas, Dorothy; Arioli, Stefania; Riso, Patrizia; Porrini, Marisa

2013-08-28

225

A comparative analysis of the intestinal metagenomes present in guinea pigs (Cavia porcellus and humans (Homo sapiens  

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Full Text Available Abstract Background Guinea pig (Cavia porcellus is an important model for human intestinal research. We have characterized the faecal microbiota of 60 guinea pigs using Illumina shotgun metagenomics, and used this data to compile a gene catalogue of its prevalent microbiota. Subsequently, we compared the guinea pig microbiome to existing human gut metagenome data from the MetaHIT project. Results We found that the bacterial richness obtained for human samples was lower than for guinea pig samples. The intestinal microbiotas of both species were dominated by the two phyla Bacteroidetes and Firmicutes, but at genus level, the majority of identified genera (320 of 376 were differently abundant in the two hosts. For example, the guinea pig contained considerably more of the mucin-degrading Akkermansia, as well as of the methanogenic archaea Methanobrevibacter than found in humans. Most microbiome functional categories were less abundant in guinea pigs than in humans. Exceptions included functional categories possibly reflecting dehydration/rehydration stress in the guinea pig intestine. Finally, we showed that microbiological databases have serious anthropocentric biases, which impacts model organism research. Conclusions The results lay the foundation for future gastrointestinal research applying guinea pigs as models for humans.

Hildebrand Falk

2012-09-01

226

Biotransformation of 1-nitropyrene to 1-aminopyrene and N-formyl-1-aminopyrene by the human intestinal microbiota  

International Nuclear Information System (INIS)

The nitropolycyclic aromatic hydrocarbon 1-nitropyrene (1-NP) is an environmental pollutant, a potent bacterial and mammalian mutagen, and a carcinogen. The metabolism of 1-NP by the human intestinal microbiota was studied using a semicontinuous culture system that simulates the colonic lumen. ["3H]-1-Nitropyrene was metabolized by the intestinal microbiota to 1-aminopyrene (1-AP) and N-formyl-1-aminopyrene (FAP) as determined by high-performance liquid chromatography (HPLC) and mass spectrometry. Twenty-four hours after the addition of ["3H]-1-NP, the formylated compound and 1-AP accounted for 20 and 80% of the total metabolism respectively. This percentage increased to 66% for FAP after 24 h following 10 d of chronic exposure to unlabeled 1-NP, suggesting metabolic adaptation to 1-NP by the microbiota. Both 1-AP and FAP have been shown to be nonmutagenic towards Salmonella typhimurium TA98, which indicates that the intestinal microflora may potentially detoxify 1-NP

1986-01-01

227

Biotransformation of 1-nitropyrene to 1-aminopyrene and N-formyl-1-aminopyrene by the human intestinal microbiota  

Energy Technology Data Exchange (ETDEWEB)

The nitropolycyclic aromatic hydrocarbon 1-nitropyrene (1-NP) is an environmental pollutant, a potent bacterial and mammalian mutagen, and a carcinogen. The metabolism of 1-NP by the human intestinal microbiota was studied using a semicontinuous culture system that simulates the colonic lumen. (/sup 3/H)-1-Nitropyrene was metabolized by the intestinal microbiota to 1-aminopyrene (1-AP) and N-formyl-1-aminopyrene (FAP) as determined by high-performance liquid chromatography (HPLC) and mass spectrometry. Twenty-four hours after the addition of (/sup 3/H)-1-NP, the formylated compound and 1-AP accounted for 20 and 80% of the total metabolism respectively. This percentage increased to 66% for FAP after 24 h following 10 d of chronic exposure to unlabeled 1-NP, suggesting metabolic adaptation to 1-NP by the microbiota. Both 1-AP and FAP have been shown to be nonmutagenic towards Salmonella typhimurium TA98, which indicates that the intestinal microflora may potentially detoxify 1-NP.

Manning, B.W.; Cerniglia, C.E.; Federle, T.W.

1986-01-01

228

Solution structure of human intestinal fatty acid binding protein: Implications for ligand entry and exit  

International Nuclear Information System (INIS)

The human intestinal fatty acid binding protein (I-FABP) is a small (131 amino acids) protein which binds dietary long-chain fatty acids in the cytosol of enterocytes. Recently, an alanine to threonine substitution at position 54 in I-FABP has been identified which affects fatty acid binding and transport, and is associated with the development of insulin resistance in several populations including Mexican-Americans and Pima Indians. To investigate the molecular basis of the binding properties of I-FABP, the 3D solution structure of the more common form of human I-FABP (Ala54) was studied by multidimensional NMR spectroscopy.Recombinant I-FABP was expressed from E. coli in the presence and absence of 15N-enriched media. The sequential assignments for non-delipidated I-FABP were completed by using 2D homonuclear spectra (COSY, TOCSY and NOESY) and 3D heteronuclear spectra(NOESY-HMQC and TOCSY-HMQC). The tertiary structure of human I-FABP was calculated by using the distance geometry program DIANA based on 2519 distance constraints obtained from the NMR data. Subsequent energy minimization was carried out by using the program SYBYL in the presence of distance constraints. The conformation of human I-FABP consists of 10 antiparallel ?-strands which form two nearly orthogonal ?-sheets of five strands each, and two short ?-helices that connect the ?-strands A and B. The interior of the protein consists of a water-filled cavity between the two ?-sheets. The NMR solution structure of human I-FABP is similar to the crystal structure of rat I-FABP.The NMR results show significant conformational variability of certain backbone segments around the postulated portal region for the entry and exit of fatty acid ligand

1997-04-01

229

Solution structure of human intestinal fatty acid binding protein: Implications for ligand entry and exit  

Energy Technology Data Exchange (ETDEWEB)

The human intestinal fatty acid binding protein (I-FABP) is a small (131 amino acids) protein which binds dietary long-chain fatty acids in the cytosol of enterocytes. Recently, an alanine to threonine substitution at position 54 in I-FABP has been identified which affects fatty acid binding and transport, and is associated with the development of insulin resistance in several populations including Mexican-Americans and Pima Indians. To investigate the molecular basis of the binding properties of I-FABP, the 3D solution structure of the more common form of human I-FABP (Ala54) was studied by multidimensional NMR spectroscopy.Recombinant I-FABP was expressed from E. coli in the presence and absence of 15N-enriched media. The sequential assignments for non-delipidated I-FABP were completed by using 2D homonuclear spectra (COSY, TOCSY and NOESY) and 3D heteronuclear spectra(NOESY-HMQC and TOCSY-HMQC). The tertiary structure of human I-FABP was calculated by using the distance geometry program DIANA based on 2519 distance constraints obtained from the NMR data. Subsequent energy minimization was carried out by using the program SYBYL in the presence of distance constraints. The conformation of human I-FABP consists of 10 antiparallel {beta}-strands which form two nearly orthogonal {beta}-sheets of five strands each, and two short {alpha}-helices that connect the {beta}-strands A and B. The interior of the protein consists of a water-filled cavity between the two {beta}-sheets. The NMR solution structure of human I-FABP is similar to the crystal structure of rat I-FABP.The NMR results show significant conformational variability of certain backbone segments around the postulated portal region for the entry and exit of fatty acid ligand.

Zhang Fengli [Boston University School of Medicine, Department of Biophysics (United States); Luecke, Christian [Johann Wolfgang Goethe-Universitaet (Germany); Baier, Leslie J. [NIDDK, NIH, Phoenix Epidemiology and Clinical Research Branch (United States); Sacchettini, James C. [Texas A and M University, Department of Biochemistry and Biophysics (United States); Hamilton, James A. [Boston University School of Medicine, Department of Biophysics (United States)

1997-04-15

230

E Durans Strain M4-5 Isolated From Human Colonic Flora Attenuates Intestinal Inflammation  

DEFF Research Database (Denmark)

PURPOSE: The aim of this study was to evaluate in vitro and in vivo effects of a unique high-butyrate-producing bacterial strain from human colonic flora, Enterococcus durans, in prevention and treatment of intestinal inflammation. METHODS: A compartmentalized Caco-2/leukocyte coculture model was used to examine the in vitro effects of E durans and its metabolite butyrate on basal and Escherichia coliâ??stimulated secretion of proinflammatory immune factors (IL-8, IL-6, and TNF-α) and the anti-inflammatory cytokine IL-10. A murine model of dextran sodium sulfate-induced colitis was used to examine in vivo effects of prevention and therapy with E durans on clinical, biochemical, and histologic parameters of inflammation. RESULTS: In the coculture model, treatment with E durans and with butyrate reduced basal as well as E coli stimulated secretion of IL-8, IL-6, and TNF-α and increased secretion of IL-10. In the in vivo murine model, preventive administration of E durans significantly ameliorated clinical disease activity index (weight loss, fecal bleeding, and stool consistency), reduced myeloperoxidase concentration in colon tissue extracts, improved histologic scores of colonic inflammation, and inhibited colonic transcription of proinflammatory immune factors. The effect of therapeutic treatment alone on these parameters was more moderate but still significant. CONCLUSIONS: We conclude that E durans strain M4 to 5 and its metabolic product butyrate induce significant anti-inflammatory effects, mediated by regulation of pro- and anti-inflammatory immune factors as well as preservation of intestine epithelial integrity, suggesting that this novel anti-inflammatory bacterium may be preferentially a useful prophylactic treatment to avoid inflammatory bowel disease.

Avram-Hananel, L.; Stock, J.

2010-01-01

231

Toxic mechanisms induced by fumonisin b1 mycotoxin on human intestinal cell line.  

Science.gov (United States)

The gastrointestinal tract is the main target of exposure to mycotoxin fumonisin B1 (FB1), common natural contaminant in food. Previous studies reported that proliferating cells are more sensitive than confluent cells to the toxic effect of FB1. This study aims to investigate, by dose- and time-dependent experiments on human colon proliferating intestinal cell line (HT-29), the modifications induced by FB1 at concentrations ranging from 0.25 to 69 ?M. The choice of highest FB1 concentration considered the low toxicity previously reported on intestinal cell lines, whereas the lowest one corresponded to the lower FBs levels permitted by European Commission Regulation. Different functional parameters were tested such as cell proliferation, oxidative status, immunomodulatory effect and changes in membrane microviscosity. In addition FB1-FITC localization in this cell line was assessed by using confocal laser scanning microscopy. Lipid peroxidation induction was the main and early (12 h) effect induced by FB1 at concentrations ranging from 0.5 to 69 ?M, followed by inhibition of cell proliferation (up to 8.6 ?M), the immunomodulatory effect (up to 17.2 ?M), by assessing IL-8 secretion, and increase in membrane microviscosity (up to 34.5 ?M). The toxic effects observed in different functional parameters were not dose-dependent and could be the consequence of the FB1 intracytoplasmatic localization as confirmed by confocal microscopy results. The different timescales and concentrations active of different functional parameters could suggest different cellular targets of FB1. PMID:24549592

Minervini, Fiorenza; Garbetta, Antonella; D'Antuono, Isabella; Cardinali, Angela; Martino, Nicola Antonio; Debellis, Lucantonio; Visconti, Angelo

2014-07-01

232

Two-dimensional gel proteome reference map of human small intestine  

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Full Text Available Abstract Background The small intestine is an important human organ that plays a central role in many physiological functions including digestion, absorption, secretion and defense. Duodenal pathologies include, for instance, the ulcer associated to Helicobacter Pylori infection, adenoma and, in genetically predisposed individuals, celiac disease. Alterations in the bowel reduce its capability to absorb nutrients, minerals and fat-soluble vitamins. Anemia and osteopenia or osteoporosis may develop as a consequence of vitamins malabsorption. Adenoma is a benign tumor that has the potential to become cancerous. Adult celiac disease patients present an overall risk of cancer that is almost twice than that found in the general population. These disease processes are not completely known. To date, a two dimensional (2D reference map of proteins expressed in human duodenal tissue is not yet available: the aim of our study was to characterize the 2D protein map, and to identify proteins of duodenal mucosa of adult individuals without duodenal illness, to create a protein database. This approach, may be useful for comparing similar protein samples in different laboratories and for the molecular characterization of intestinal pathologies without recurring to the use of surgical material. Results The enrolled population comprised five selected samples (3 males and 2 females, aged 19 to 42, taken from 20 adult subjects, on their first visit at the gastroenterology unit for a suspected celiac disease, who did not turn to be affected by any duodenal pathology after gastrointestinal and histological evaluations. Proteins extracted from the five duodenal mucosal specimens were singly separated by 2D gel electrophoresis. After image analysis of each 2D gel, 179 protein spots, representing 145 unique proteins, from 218 spots tested, were successfully identified by MALDI-TOF ms analysis. Normalized volumes, for each protein, have been reported for every gel. Proteins have been grouped according to their biological/metabolic functions. Conclusion This study represents to date the first detailed and reproducible 2D protein map of human duodenum. Spots identifications, reported in a database, will be helpful to identify the variability in protein expression levels, in isoforms expression, or in post-translational modifications associated to pathology or to a therapy.

Canzonieri Vincenzo

2009-03-01

233

Effect of absorbable and nonabsorbable sugars on intestinal calcium absorption in humans  

International Nuclear Information System (INIS)

The effects of glucose, galactose, and lactitol on intestinal calcium absorption and gastric emptying were studied in 9, 8, and 20 healthy subjects, respectively. Calcium absorption was measured by using a double-isotope technique and the kinetic parameters were obtained by a deconvolution method. The gastric emptying rate was determined with /sup 99m/Tc-diethylenetriaminepentaacetic acid and was expressed as the half-time of the emptying curve. Each subject was studied under two conditions: (a) with calcium alone and (b) with calcium plus sugar. Glucose and galactose increased the calcium mean transit time and improved the total fractional calcium absorption by 30% (p less than 0.02). Lactitol decreased the mean rate of absorption (p less than 0.001) and reduced the total fractional calcium absorption by 15% (p less than 0.001). The gastric emptying rate did not appear to influence directly the kinetic parameters of calcium absorption. These results show that both glucose and galactose exert the same stimulatory effect as lactose on calcium absorption in subjects with normal lactase whereas lactitol mimics the effects of lactose in lactase-deficient patients. Thus the absorbability of sugars determines their effect on calcium absorption

1989-01-01

234

Regulation of human intestinal mast cells by stem cell factor and IL-4.  

Science.gov (United States)

Mature human mast cells are tissue-residing, key effector cells of immediate allergic reactions. Moreover, mast cells have been recognized as a potent cellular source of multiple cytokines, suggesting an important role in immunoregulation and host defense. Here, we report on the regulation of mature human mast cells isolated from intestinal tissues by stem cell factor (SCF) and interleukin (IL)-4. SCF is substantially necessary for mast cell survival and induces marginal mast cell proliferation in vitro, whereas IL-4 by itself has no effects on mast cell survival or proliferation. Most interestingly, in synergy with SCF, IL-4 strongly enhances mast cell proliferation. In the presence of SCF, mast cells predominantly produce pro-inflammatory cytokines including tumor necrosis factor (TNF)-alpha, IL-1beta, IL-6, IL-8, IL-16, and IL-18. Addition of IL-4 to the culture medium induces the expression of Th2-type cytokines (IL-3, IL-5 and IL-13), and a downregulation of pro-inflammatory cytokines, namely IL-6. Furthermore, SCF by itself supports the predominance of the tryptase/chymase double-positive mast cell subtype MCTC whereas the addition of IL-4 supports the chymase negative MCT subtype. In conclusion, SCF may primarily regulate resident mast cell survival, whereas IL-4 may promote local proliferation of mast cells and their expression of Th2-type cytokines. PMID:11292028

Lorentz, A; Bischoff, S C

2001-02-01

235

Digoxin inhibition of relaxation induced by prostacyclin and vasoactive intestinal polypeptide in small human placental arteries  

DEFF Research Database (Denmark)

Small chorionic plate arteries were obtained from human placentae following normal vaginal delivery. Tubal vascular preparations were dissected, mounted in organ baths, and their isometric tension was recorded. Digoxin (10(-6) M) caused a rise in basic tension, reaching a maximum of 17 per cent of contractions induced by potassium (124 mM) depolarization. Pretreatment with digoxin did not significantly influence the concentration-dependent contractile responses to 5-hydroxytryptamine and prostaglandin F2 alpha (PGF2 alpha). In preparations contracted with PGF2 alpha, cumulative addition of prostacyclin (PGI2) and vasoactive intestinal polypeptide (VIP) produced concentration dependent relaxations. Digoxin (10(-8) to 10(-6) M) inhibited and finally abolished these relaxant effects of PGI2 and VIP in a concentration-dependent fashion. Pretreatment by digoxin (10(-8) to 10(-6) M) diminished the relaxant effect of sodium nitroprusside, but the effect was less pronounced than that on PGI2- and VIP-induced relaxation. As PGI2 and VIP may be of importance for the maintenance of a low resistance of the fetal placental vascular bed, the finding that digoxin decreases the vasodilating effects of these agents might imply effects on placental resistance of cardiac glycosides when used in late human pregnancy.

Maigaard, S; Forman, Axel

1985-01-01

236

Effect of broad-spectrum parenteral antibiotics on "colonization resistance" of intestinal microflora of humans.  

Science.gov (United States)

Studies with animals have shown that the normal intestinal microflora protects against colonization by new strains ("colonization resistance") and that this protective effect may be related to the anaerobic component of the microflora. However, colonization resistance has not been shown in humans. We administered cefoxitin, piperacillin, cefoperazone, and aztreonam intravenously to healthy subjects for 9 days and monitored the acquisition of new isolates in the fecal flora. Seven of sixteen antibiotic-treated subjects but none of four untreated controls became colonized by gram-negative bacilli. However, there was no correlation between colonization and the particular drug given or the extent of suppression of anaerobes or of any other component of the fecal microflora. Cefoxitin and piperacillin were associated with the greatest increases in the numbers of drug-resistant bacteria and in fecal beta-lactamase content. The results of this study support the concept that colonization resistance occurs in humans and is diminished by antibiotic administration but fail to support the hypothesis that resistance is related to the anaerobic microflora. PMID:3496848

Barza, M; Giuliano, M; Jacobus, N V; Gorbach, S L

1987-05-01

237

The Intestinal Archaea Methanosphaera stadtmanae and Methanobrevibacter smithii Activate Human Dendritic Cells  

Science.gov (United States)

The methanoarchaea Methanosphaera stadtmanae and Methanobrevibacter smithii are known to be part of the indigenous human gut microbiota. Although the immunomodulatory effects of bacterial gut commensals have been studied extensively in the last decade, the impact of methanoarchaea in human's health and disease was rarely examined. Consequently, we studied and report here on the effects of M. stadtmanae and M. smithii on human immune cells. Whereas exposure to M. stadtmanae leads to substantial release of proinflammatory cytokines in monocyte-derived dendritic cells (moDCs), only weak activation was detected after incubation with M. smithii. Phagocytosis of M. stadtmanae by moDCs was demonstrated by confocal microscopy as well as transmission electronic microscopy (TEM) and shown to be crucial for cellular activation by using specific inhibitors. Both strains, albeit to different extents, initiate a maturation program in moDCs as revealed by up-regulation of the cell-surface receptors CD86 and CD197 suggesting additional activation of adaptive immune responses. Furthermore, M. stadtmanae and M. smithii were capable to alter the gene expression of antimicrobial peptides in moDCs to different extents. Taken together, our findings strongly argue that the archaeal gut inhabitants M. stadtmanae and M. smithii are specifically recognized by the human innate immune system. Moreover, both strains are capable of inducing an inflammatory cytokine response to different extents arguing that they might have diverse immunomodulatory functions. In conclusion, we propose that the impact of intestinal methanoarchaea on pathological conditions involving the gut microbiota has been underestimated until now.

Bang, Corinna; Weidenbach, Katrin; Gutsmann, Thomas

2014-01-01

238

A layered model of a virtual human intestine for surgery simulation.  

Science.gov (United States)

In this paper, we propose a new approach to simulate the small intestine in a context of laparoscopic surgery. The ultimate aim of this work is to simulate the training of a basic surgical gesture in real-time: moving aside the intestine to reach hidden areas of the abdomen. The main problem posed by this kind of simulation is animating the intestine. The problem comes from the nature of the intestine: a very long tube which is not isotropically elastic, and is contained in a volume that is small when compared to the intestine's length. It coils extensively and collides with itself in many places. To do this, we use a layered model to animate the intestine. The intestine's axis is animated as a linear mechanical component. A specific sphere-based model handles contacts and self-collisions. A skinning model is used to create the intestine's volume around the axis. This paper discusses and compares three different representations for skinning the intestine: a parametric surface model and two implicit surface models. The first implicit surface model uses point skeletons while the second uses local convolution surfaces. Using these models, we obtained good-looking results in real-time. Some videos of this work can be found in the online version at doi: 10.1016/j.media.2004.11.006 and at www-imagis.imag.fr/Publications/2004/FLAMCFC04. PMID:15721228

France, L; Lenoir, J; Angelidis, A; Meseure, P; Cani, M-P; Faure, F; Chaillou, C

2005-04-01

239

Specific binding of lactoferrin to Escherichia coli isolated from human intestinal infections  

Energy Technology Data Exchange (ETDEWEB)

The degrees of human lactoferrin (HLf) and bovine lactoferrin (BLf) binding in 169 Escherichia coli strains isolated from human intestinal infections, and in an additional 68 strains isolated from healthy individuals, were examined in a {sup 125}I-labelled protein binding assay. The binding was expressed as a percentage calculated from the total labelled ligand added to bacteria. The HLf and BLf binding to E. coli was in the range 3.7 to 73.4% and 4.8 to 61.6%, respectively. Enterotoxigenic strains demonstrated a significantly higher HLf binding (median = 19%) than enteropathogenic, enteroinvasive, enterohaemorrhagic strains or normal intestinal E. coli isolates (medians 6 to 9). Enteropathogenic strains belonging to serotypes O44 and O127 demonstrated significantly higher HLf binding compared to O26, O55, O111, O119 and O126. No significant differences in the degree of HLf or BLf binding were found between aerobactin-producing and non-producing strains. The interaction was further characterized in a high Lf-binging EPEC strain, E34663 (serotype O127). The binding was stable in the pH range 4.0 to 7.5, did not dissociate in the presence of 2M NaCl or 2M urea, and reached saturation within two h. Unlabelled HLf and BLf displaced the {sup 125}I-HLf binding to E34663 in a dose-dependent manner. Apo- and iron-saturated forms of Lf demonstrated similar binding to E34663. Among various unlabelled subephithelial matrix proteins and carbohydrates tested (in 10{sup 4}-fold excess) only fibronectin and fibrinogen caused a moderate inhibition of {sup 125}I-HLf binding. According to Scatchard plot analysis, 5,400 HLf-binding sites/cell, with an affinity constant (K{sub a}) of 1.4 x 10{sup -7} M, were estimated in strain E34663. These data establish the presence of a specific Lf-binding mechanism in E. coli. (au).

Naidu, S.S.; Erdei, J.; Forsgren, A.; Naidu, A.S. (Departments of Medical Microbiology, Malmoe General Hospital (Sweden)); Czirok, E.; Gado, I. (National Institute of Hygiene, Budapest (Hungary)); Kalfas, S. (School of Dentistry, University of Lund, Malmoe (Sweden)); Thoren, A. (Infectious Diseases, Malmoe General Hospital (Sweden))

1991-01-01

240

Mast cells modulate transport of CD23/IgE/antigen complex across human intestinal epithelial barrier  

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Full Text Available Background: Food allergy and chronic intestinal inflammation are common in western countries. The complex of antigen/IgE is taken up into the body from the gut lumen with the aid of epithelial cell-derived CD23 (low affinity IgE receptor II that plays an important role in the pathogenesis of intestinal allergy. This study aimed to elucidate the role of mast cell on modulation of antigen/IgE complex transport across intestinal epithelial barrier. Methods: Human intestinal epithelial cell line HT29 cell monolayer was used as a study platform. Transepithelial electric resistance (TER and permeability to ovalbumin (OVA were used as the markers of intestinal epithelial barrier function that were recorded in response to the stimulation of mast cell-derived chemical mediators. Results: Conditioned media from naïve mast cell line HMC-1 cells or monocyte cell line THP-1 cells significantly upregulated the expression of CD23 and increased the antigen transport across the epithelium. Treatment with stem cell factor (SCF, nerve growth factor (NGF, retinoic acid (RA or dimethyl sulphoxide (DMSO enhanced CD23 expression in HT29 cells. Conditioned media from SCF, NGF or RA-treated HMC-1 cells, and SCF, NGF, DMSO or RA-treated THP-1 cells enhanced immune complex transport via enhancing the expression of the CD23 in HT29 cells and the release of inflammatory mediator TNF-?. Nuclear factor kappa B inhibitor, tryptase and TNF-? inhibited the increase in CD23 in HT29 cells and prevents the enhancement of epithelial barrier permeability. Conclusions: Mast cells play an important role in modulating the intestinal CD23 expression and the transport of antigen/IgE/CD23 complex across epithelial barrier.

Ping-Chang Yang

2009-06-01

 
 
 
 
241

Metformin Transport by a Newly Cloned Proton-Stimulated Organic Cation Transporter (Plasma Membrane Monoamine Transporter) Expressed in Human Intestine  

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Metformin is a widely used oral antihyperglycemic drug for the treatment of type II diabetes mellitus. The intestinal absorption of metformin is dose-dependent and involves an active, saturable uptake process. Metformin has been shown to be transported by the human organic cation transporters 1 and 2 (hOCT1–2). We recently cloned and characterized a novel proton-activated organic cation transporter, plasma membrane monoamine transporter (PMAT). We previously showed that PMAT transports many...

Zhou, Mingyan; Xia, Li; Wang, Joanne

2007-01-01

242

A Role for the Epidermal Growth Factor Receptor Signaling in Development of Intestinal Serrated Polyps in Mice and Humans  

Science.gov (United States)

Background & Aims Epithelial cancers can be initiated by activating mutations in components of the mitogen-activated protein kinase (MAPK) signaling pathway such as BRAF, KRAS, or epidermal growth factor receptor (EGFR). Human intestinal serrated polyps are a heterogeneous group of benign lesions, but some progress to colorectal cancer. Tumors that arise from these polyps frequently contain activating mutations in BRAF or KRAS, but little is known about the role of EGFR activation in their development. Methods Polyp samples were obtained from adults during screening colonoscopies at Mount Sinai Hospital in New York. We measured levels of EGFR protein and phosphorylation in human serrated polyps by immunohistochemical and immunoblot analyses. We generated transgenic mice that express the ligand for EGFR, HB-EGF, in the intestine. Results EGFR and the extracellular-regulated kinases (ERK)1/2 were phosphorylated in serrated areas of human hyperplastic polyps (HPPs), sessile serrated adenomas, and traditional serrated adenomas. EGFR and ERK1/2 were phosphorylated in the absence of KRAS or BRAF activating mutations in a subset of HPP. Transgenic expression of the EGFR ligand HB-EGF in the intestines of mice promoted development of small cecal serrated polyps. Mice that expressed a combination of HB-EGF and US28 (a constitutively active, G-protein–coupled receptor that increases processing of HB-EGF from the membrane) rapidly developed large cecal serrated polyps. These polyps were similar to HPPs and had increased phosphorylation of EGFR and ERK1/2 within the serrated epithelium. Administration of pharmacologic inhibitors of EGFR or MAP kinase to these transgenic mice significantly reduced polyp development. Conclusions Activation of EGFR signaling in the intestine of mice promotes development of serrated polyps. EGFR signaling is also activated in human HPPs, sessile serrated adenomas, and traditional serrated adenomas.

Bongers, Gerold; Muniz, Luciana R.; Pacer, Michelle E.; Iuga, Alina C.; Thirunarayanan, Nanthakumar; Slinger, Erik; Smit, Martine J.; Reddy, E. Premkumar; Mayer, Lloyd; Furtado, Glaucia C.; Harpaz, Noam; Lira, Sergio A.

2012-01-01

243

Reduction of azo dyes and nitroaromatic compounds by bacterial enzymes from the human intestinal tract  

Energy Technology Data Exchange (ETDEWEB)

Several anaerobic bacteria from the human intestinal tract are capable of reducing azo dyes and nitropolycyclic aromatic hydrocarbons to the corresponding aromatic amines with enzymes that have azoreductase and nitroreductase activities. The majority of bacteria with these activities belong to the genera Clostridium and Eubacterium. The azoreductases and nitroreductases from three Clostridium strains and one Eubacterium strain were studied. Both enzymes were produced constitutively in each of the bacteria; the enzymes from various bacteria had different electrophoretic mobilities. The azoreductases from all of the bacteria had immunological homology, as was evident from the cross-reactivity of an antibody raised against the azoreductase of C perfringens with azoreductases from other bacteria. Comparison of azoreductases and nitroreductases showed that they both had identical electrophoretic mobilities on polyacrylamide gels and reacted with the antibody against the azoreductase from C. perfringens. Furthermore, the nitroaromatic compounds competitively inhibited the azoreductase activity. The data indicate that the reduction of both nitroaromatic compounds and azo dyes may be carried out by the same enzyme, which is possibly a flavin adenine dinucleotide dehydrogenase that is synthesized throughout the cell and not associated with any organized subcellular structure. 15 refs., 1 fig., 2 tabs.

Rafii, F.; Cerniglia, C.E. [Food and Drug Administration, Jefferson, AR (United States)

1995-06-01

244

Butyrate stimulates IL-32? expression in human intestinal epithelial cell lines  

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Full Text Available AIM: To investigate the effects of butyrate on interleukin (IL-32? expression in epithelial cell lines.METHODS: The human intestinal epithelial cell lines HT-29, SW480, and T84 were used. Intracellular IL-32? was determined by Western blotting analyses. IL-32? mRNA expression was analyzed by real-time polymerase chain reaction.RESULTS: Acetate and propionate had no effects on IL-32? mRNA expression. Butyrate significantly enhanced IL-32? expression in all cell lines. Butyrate also up-regulated IL-1?-induced IL-32? mRNA expression. Butyrate did not modulate the activation of phosphatidylinositol 3-kinase (PI3K, a mediator of IL-32? expression. Like butyrate, trichostatin A, a histone deacetylase inhibitor, also enhanced IL-1?-induced IL-32? mRNA expression.CONCLUSION: Butyrate stimulated IL-32? expression in epithelial cell lines. An epigenetic mechanism, such as histone hyperacetylation, might be involved in the action of butyrate on IL-32? expression.

Ayako Kobori, Shigeki Bamba, Hirotsugu Imaeda, Hiromitsu Ban, Tomoyuki Tsujikawa, Yasuharu Saito, Yoshihide Fujiyama, Akira Andoh

2010-05-01

245

In vitro DNA-damaging effects of intestinal and related tetrapyrroles in human cancer cells.  

Science.gov (United States)

Epidemiological studies report a negative association between circulating bilirubin concentrations and the risk for cancer and cardiovascular disease. Structurally related tetrapyrroles also possess in vitro anti-genotoxic activity and may prevent mutation prior to malignancy. Furthermore, few data suggest that tetrapyrroles exert anti-carcinogenic effects via induction of cell cycle arrest and apoptosis. To further investigate whether tetrapyrroles provoke DNA-damage in human cancer cells, they were tested in the single cell gel electrophoresis assay (SCGE). Eight tetrapyrroles (unconjugated bilirubin, bilirubin ditaurate, biliverdin, biliverdin-/bilirubin dimethyl ester, urobilin, stercobilin and protoporphyrin) were added to cultured Caco2 and HepG2 cells and their effects on comet formation (% tail DNA) were assessed. Flow cytometric assessment (apoptosis/necrosis, cell cycle, intracellular radical species generation) assisted in revealing underlying mechanisms of intracellular action. Cells were incubated with tetrapyrroles at concentrations of 0.5, 5 and 17?M for 24h. Addition of 300?M tertiary-butyl hydroperoxide to cells served as a positive control. Tetrapyrrole incubation mostly resulted in increased DNA-damage (comet formation) in Caco2 and HepG2 cells. Tetrapyrroles that are concentrated within the intestine, including protoporphyrin, urobilin and stercobilin, led to significant comet formation in both cell lines, implicating the compounds in inducing DNA-damage and apoptosis in cancer cells found within organs of the digestive system. PMID:23246570

Mölzer, Christine; Pfleger, Barbara; Putz, Elisabeth; Roßmann, Antonia; Schwarz, Ursula; Wallner, Marlies; Bulmer, Andrew C; Wagner, Karl-Heinz

2013-02-15

246

Mangiferin aglycone attenuates radiation-induced damage on human intestinal epithelial cells.  

Science.gov (United States)

Recent studies suggest that mangiferin aglycone (norathyriol) has great potential as a novel radioprotector without any known toxic side effects. In this study, we assessed the protective effects of mangiferin aglycone against radiation-induced injuries on normal human intestinal epithelial cells (HIECs), while using mangiferin as a reference compound. The in vitro experiments showed that pretreatment of either mangiferin aglycone or mangiferin could inhibit cytotoxic effects of ionizing irradiation (IR) on HIECs. Cellular changes were estimated by measuring cell viability, clonogenic surviving rate, and apoptotic rate. Compared to mangiferin, we found mangiferin aglycone had greater radioprotective effects of mangiferin aglycone on HIECs. It has been demonstrated that the cytotoxicity of ionizing radiation relates to its capacity to induce DNA damage. In view of this, we monitored DNA double-strand breaks (DSBs) using ?H2AX foci formation to test whether mangiferin aglycone and mangiferin could modulate genotoxic effects of radiation. It shows that mangiferin aglycone could eliminate 46.8% of the total DSBs of the cells exposed to 2 Gy IR, which is significantly better than mangiferin. Complementing earlier results from our group, it appears possible to conclude that mangiferin aglycone presents potential useful effects on IR-induced damage and may be a better radioprotective agent than mangiferin therapeutically. PMID:22422649

Lei, Jixiao; Zhou, Chuanfeng; Hu, Honggang; Hu, Lina; Zhao, Meijia; Yang, Yanyong; Chuai, Yunhai; Ni, Jin; Cai, Jianming

2012-08-01

247

Prediction of Human Intestinal Absorption by GA Feature Selection and Support Vector Machine Regression  

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Full Text Available QSAR (Quantitative Structure Activity Relationships models for the prediction of human intestinal absorption (HIA were built with molecular descriptors calculated by ADRIANA.Code, Cerius2 and a combination of them. A dataset of 552 compounds covering a wide range of current drugs with experimental HIA values was investigated. A Genetic Algorithm feature selection method was applied to select proper descriptors. A Kohonen's self-organizing Neural Network (KohNN map was used to split the whole dataset into a training set including 380 compounds and a test set consisting of 172 compounds. First, the six selected descriptors from ADRIANA.Code and the six selected descriptors from Cerius2 were used as the input descriptors for building quantitative models using Partial Least Square (PLS analysis and Support Vector Machine (SVM Regression. Then, another two models were built based on nine descriptors selected by a combination of ADRIANA.Code and Cerius2 descriptors using PLS and SVM, respectively. For the three SVM models, correlation coefficients (r of 0.87, 0.89 and 0.88 were achieved; and standard deviations (s of 10.98, 9.72 and 9.14 were obtained for the test set.

Zongyuan Cai

2008-10-01

248

Human intestinal spirochetosis is significantly associated with sessile serrated adenomas/polyps.  

Science.gov (United States)

It remains unclear whether or not human intestinal spirochetosis (HIS) has any associated symptoms or lesions. In this study, we assessed the prevalence of HIS in sessile serrated adenomas/polyps (SSA/Ps) and their possible association. Following identification of early cecal cancer with SSA/P accompanied by a colonization of HIS, we went on to conduct a retrospective case-control study using endoscopically resected SSA/P specimens to examine the frequency of HIS infection in SSA/Ps. Nineteen SSA/P cases and 172 controls were obtained. The rate of HIS infection was significantly higher at 52.6% (10/19) in the SSA/P cases compared to the controls at 8.1% (14/172). Our SSA/P series were associated with a remarkably higher rate of HIS than controls or than previously reported. This is the first report to provide evidence for potential association between HIS and SSA/Ps. PMID:24767254

Omori, Saori; Mabe, Katsuhiro; Hatanaka, Kanako; Ono, Masayoshi; Matsumoto, Mio; Takahashi, Masakazu; Yoshida, Takeshi; Ono, Shoko; Shimizu, Yuichi; Sugai, Nozomi; Suzuki, Akira; Katsuki, Shinichi; Fujii, Takahiro; Kato, Mototsugu; Asaka, Masahiro; Sakamoto, Naoya

2014-07-01

249

Regioselective Glucuronidation of Oxyresveratrol, a Natural Hydroxystilbene, by Human Liver and Intestinal Microsomes and Recombinant UGTs.  

Science.gov (United States)

Oxyresveratrol (OXY) is a natural hydroxystilbene that shows similar bioactivity but better water solubility than resveratrol. This study aims to characterize its glucuronidation kinetics in human liver (HLMs) and intestinal (HIMs) microsomes and identify the main UDP-glucuronosyltransferase (UGT) isoforms involved. Three and four mono-glucuronides of OXY were generated in HIMs and HLMs, respectively, with oxyresveratrol-2-O-?-d-glucuronosyl (G4) as the major metabolite in both organs. The kinetics of G4 formation fit a sigmoidal model in HLMs and biphasic kinetics in HIMs. Multiple UGT isoforms catalyzed G4 formation with the highest activity observed with UGT1A9 followed by UGT1A1. G4 formation by both isoforms followed substrate inhibition kinetics. Propofol (UGT1A9 inhibitor) effectively blocked G4 generation in HLMs (IC50 63.7 ± 11.6 µM), whereas the UGT1A1 inhibitor bilirubin only produced partial inhibition in HLMs and HIMs. These findings shed light on the metabolic mechanism of OXY and arouse awareness of drug interactions. PMID:24256624

Hu, Nan; Mei, Mei; Ruan, Jianqing; Wu, Wenjin; Wang, Yitao; Yan, Ru

2014-06-25

250

Modulation of chromatin remodelling induced by the freshwater cyanotoxin cylindrospermopsin in human intestinal caco-2 cells.  

Science.gov (United States)

Cylindrospermopsin (CYN) is a cyanotoxin that has been recognised as an emerging potential public health risk. Although CYN toxicity has been demonstrated, the mechanisms involved have not been fully characterised. To identify some key pathways related to this toxicity, we studied the transcriptomic profile of human intestinal Caco-2 cells exposed to a sub-toxic concentration of CYN (1.6 µM for 24hrs) using a non-targeted approach. CYN was shown to modulate different biological functions which were related to growth arrest (with down-regulation of cdkn1a and uhrf1 genes), and DNA recombination and repair (with up-regulation of aptx and pms2 genes). Our main results reported an increased expression of some histone-modifying enzymes (histone acetyl and methyltransferases MYST1, KAT5 and EHMT2) involved in chromatin remodelling, which is essential for initiating transcription. We also detected greater levels of acetylated histone H2A (Lys5) and dimethylated histone H3 (Lys4), two products of these enzymes. In conclusion, CYN overexpressed proteins involved in DNA damage repair and transcription, including modifications of nucleosomal histones. Our results highlighted some new cell processes induced by CYN. PMID:24921660

Huguet, Antoine; Hatton, Aurélie; Villot, Romain; Quenault, Hélène; Blanchard, Yannick; Fessard, Valérie

2014-01-01

251

Intestinal parasitic infections and eosinophilia in an human immunedeficiency virus positive population in Honduras  

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Full Text Available The occurrence of intestinal parasites, their regional distribution and their relations to eosinophilia were studied in 133 human immunodeficiency virus (HIV positive individuals from Honduras. After signing an informed consent, participants answered a socio-demographic and risk factor questionnaire, a complete physical examination, medical history, and a series of laboratory tests. All participants were HIV positive but not acquired immunodeficiency syndrome positive. Of them, 67% were co-infected with pathogen and non pathogen parasites. Overall occurrence of nematodes was: 44.3% for Trichuris trichiura, 24% for Ascaris lumbricoides, 12% for Hookworm and 7.5% for Strongyloides stercoralis. No cases of Giardia lamblia, acute amebiasis or cryptosporidiasis were diagnosed. Mean eosinophil percents for participants were consistently and significantly higher in infected than in non infected individuals: 22% for Hookworm vs 7.2% (p < 0.001, 11% for Trichuris compared to 5.2% (p < 0.001, 13.2% compared to 7.5% for S. stercoralis (p < 0.05, and 12% compared to 6% for Ascaris cases (p < 0.05. Helminths and non pathogenic protozoa, as single or mixed infections, occurred among the participants. There was a strong correlation between eosinophilia and helminthiasis infections; however, none was identified between CD4 levels and eosinophilia. Because parasitic infections aggravate malnutrition and promote a disbalanced Th2 response in a potentially immuno-compromised host, their effect on HIV disease progression needs further study, mainly in countries were HIV and parasitic infections are highly prevalent.

Rina G Kaminsky

2004-11-01

252

Human Capital Externalities: Evidence from the Transition Economy of Russia  

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The paper tests for the existence of human capital externalities, more precisely those stemming from higher education, using a micro-level approach: the Mincerian wage regression augmented with the average level of education in a local geographical area (city). To solve identification problems arising due to endogeneity of average education the study exploits a natural experiment provided by the process of economic transition in the former communist economies. We argue that the educational st...

Muravyev, Alexander

2006-01-01

253

Long-lived plasma cells from human small intestine biopsies secrete immunoglobulins for many weeks in vitro.  

Science.gov (United States)

To understand the biology of Ab-secreting cells in the human small intestine, we examined Ab production of intestinal biopsies kept in culture. We found sustained IgA and IgM secretion as well as viable IgA- or IgM-secreting cells after >4 wk of culture. The Ab-secreting cells were nonproliferating and expressing CD27 and CD138, thus having a typical plasma cell phenotype. Culturing of biopsies without tissue disruption gave the highest Ab production and plasma cell survival suggesting that the environment regulates plasma cell longevity. Cytokine profiling of the biopsy cultures demonstrated a sustained presence of IL-6 and APRIL. Blocking of the activity of endogenous APRIL and IL-6 with BCMA-Fc and anti-human IL-6 Ab demonstrated that both these factors were essential for plasma cell survival and Ab secretion in the biopsy cultures. This study demonstrates that the human small intestine harbors a population of nonproliferating plasma cells that are instructed by the microenvironment for prolonged survival and Ab secretion. PMID:21841131

Mesin, Luka; Di Niro, Roberto; Thompson, Keith M; Lundin, Knut E A; Sollid, Ludvig M

2011-09-15

254

The angiogenic effect of probiotic Bacillus polyfermenticus on human intestinal microvascular endothelial cells is mediated by IL-8  

Science.gov (United States)

Angiogenesis is required for wound healing and repair, but dysregulated angiogenesis is involved in gastrointestinal inflammation. Bacillus polyfermenticus (B.P.) is a probiotic bacterium clinically used for a variety of intestinal disorders in East Asia. Here we investigated the effect of B.P. on angiogenesis of human intestinal microvascular endothelial cells (HIMECs) and wound healing in intestinal mucosa. Exposure of HIMECs to the conditioned medium of B.P. cultures (B.P. CM) increased cell migration, permeability, and tube formation. Production of the proangiogenic cytokine IL-8 was increased by B.P. CM, and neutralizing antibodies against IL-8 or IL-8 receptor CXCR2 reduced tube formation as well as actin stress fiber formation. B.P. CM also increased NF-?B activation, and inhibitors of NF-?B suppressed B.P. CM-induced tube formation and IL-8 production. Furthermore, B.P. facilitated recovery of mice from colitis as shown by increased body weight and reduced rectal bleeding and histological severity. B.P. also increased angiogenesis and mouse IL-8 production in the mucosal layer. Collectively, these results show that B.P. increases angiogenesis of HIMECs in a NF-?B/IL-8/CXCR2-dependent manner. Moreover, B.P. promotes angiogenesis in the mucosa during recovery of mice from colitis, suggesting that this probiotic may be clinically used to facilitate intestinal wound healing.

Choi, Yoon Jeong; Kim, Cho Hee; Fiocchi, Claudio; Pothoulakis, Charalabos

2009-01-01

255

Animal models of intestinal fibrosis: new tools for the understanding of pathogenesis and therapy of human disease.  

Science.gov (United States)

Fibrosis is a serious condition complicating chronic inflammatory processes affecting the intestinal tract. Advances in this field that rely on human studies have been slow and seriously restricted by practical and logistic reasons. As a consequence, well-characterized animal models of intestinal fibrosis have emerged as logical and essential systems to better define and understand the pathophysiology of fibrosis. In point of fact, animal models allow the execution of mechanistic studies as well as the implementation of clinical trials with novel, pathophysiology-based therapeutic approaches. This review provides an overview of the currently available animal models of intestinal fibrosis, taking into consideration the methods of induction, key characteristics of each model, and underlying mechanisms. Currently available models will be classified into seven categories: spontaneous, gene-targeted, chemical-, immune-, bacteria-, and radiation-induced as well as postoperative fibrosis. Each model will be discussed in regard to its potential to create research opportunities to gain insights into the mechanisms of intestinal fibrosis and stricture formation and assist in the development of effective and specific antifibrotic therapies. PMID:22878121

Rieder, Florian; Kessler, Sean; Sans, Miquel; Fiocchi, Claudio

2012-10-01

256

The kinetic, mechanistic and cytomorphological effects of palytoxin in human intestinal cells (Caco-2) explain its lower-than-parenteral oral toxicity  

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Palytoxin is one of the most toxic marine toxins known. Distributed worldwide, it poses a potential human health risk linked to the consumption of contaminated seafood. Despite its high parenteral toxicity, the lethal oral dose of palytoxin is several times higher than the intraperitoneal lethal dose. In the present study, we investigated the passage of palytoxin through the human intestinal barrier by employing a well-characterized and accepted in vitro model of intestinal permeability that ...

2013-01-01

257

Comparison of DNA extraction kits for PCR-DGGE analysis of human intestinal microbial communities from fecal specimens  

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Full Text Available Abstract Background The influence of diet on intestinal microflora has been investigated mainly using conventional microbiological approaches. Although these studies have advanced knowledge on human intestinal microflora, it is imperative that new methods are applied to facilitate scientific progress. Culture-independent molecular fingerprinting method of Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis (PCR-DGGE has been used to study microbial communities in a variety of environmental samples. However, these protocols must be optimized prior to their application in order to enhance the quality and accuracy of downstream analyses. In this study, the relative efficacy of four commercial DNA extraction kits (Mobio Ultra Clean® Fecal DNA Isolation Kit, M; QIAamp® DNA Stool Mini Kit, Q; FastDNA® SPIN Kit, FSp; FastDNA® SPIN Kit for Soil, FSo were evaluated. Further, PCR-DGGE technique was also assessed for its feasibility in detecting differences in human intestinal bacterial fingerprint profiles. Method Total DNA was extracted from varying weights of human fecal specimens using four different kits, followed by PCR amplification of bacterial 16S rRNA genes, and DGGE separation of the amplicons. Results Regardless of kit, maximum DNA yield was obtained using 10 to 50 mg (wet wt of fecal specimens and similar DGGE profiles were obtained. However, kits FSp and FSo extracted significantly larger amounts of DNA per g dry fecal specimens and produced more bands on their DGGE profiles than kits M and Q due to their use of bead-containing lysing matrix and vigorous shaking step. DGGE of 16S rRNA gene PCR products was suitable for capturing the profiles of human intestinal microbial community and enabled rapid comparative assessment of inter- and intra-subject differences. Conclusion We conclude that extraction kits that incorporated bead-containing lysing matrix and vigorous shaking produced high quality DNA from human fecal specimens (10 to 50 mg, wet wt that can be resolved as bacterial community fingerprints using PCR-DGGE technique. Subsequently, PCR-DGGE technique can be applied for studying variations in human intestinal microbial communities.

Nakatsu Cindy H

2010-05-01

258

Conversion of 5-fluorocytosine to 5-fluorouracil by human intestinal microflora  

International Nuclear Information System (INIS)

5-Fluorocytosine (FC) is used to treat systemic fungal infections in man. Its clinical effectiveness has been limited by hematologic toxicity which may be secondary to the formation of 5-fluorouracil (FU). It is unclear how FU is formed since human cells lack cytosine deaminase. The present study examined if intestinal microflora (IMF) could convert FC to FU in man. An in vitro semicontinuous culture system was inoculated with human feces and maintained with sterile nutrient suspension. The microbial community was assessed for cell count and anaerobes as well as formation of volatile fatty acids and CH_4. The system approximated that believed to occur in vivo. The study was initiated with addition of purified [6-"1"4C]-FC. Unlabelled FC was then added to the system daily for 2 weeks following which [6-"1"4C]-FC was again added. Following each addition of [6-"1"4C]-FC, samples were removed at 2,4,8,24,48,72, and 96 hr. Utilizing HPLC, FC and FU could be separated with quantitation of radioactivity in each peak. Following the initial dose, no detectable FU was observed during the first 8 hr, but after 24 hr increasing levels were detected (9.42 ?g FU/ml after 4 days). Following chronic administration of FC, increased levles of FU were noted without an 8 hr lag time in the production of FU (31.86 ?g FU/ml after 4 days). In summary, these studies demonstrate that IMF can convert FC to FU possibly accounting for toxicity observed following administration of FC

1986-03-01

259

Rapid generation of rotavirus-specific human monoclonal antibodies from small-intestinal mucosa.  

Science.gov (United States)

The gut mucosal surface is efficiently protected by Abs, and this site represents one of the richest compartments of Ab-secreting cells in the body. A simple and effective method to generate Ag-specific human monoclonal Abs (hmAbs) from such cells is lacking. In this paper, we describe a method to generate hmAbs from single Ag-specific IgA- or IgM-secreting cells of the intestinal mucosa. We found that CD138-positive plasma cells from the duodenum expressed surface IgA or IgM. Using eGFP-labeled virus-like particles, we harnessed the surface Ig expression to detect rotavirus-specific plasma cells at low frequency (0.03-0.35%) in 9 of 10 adult subjects. Single cells were isolated by FACS, and as they were viable, further testing of secreted Abs by ELISPOT and ELISA indicated a highly specific selection procedure. Ab genes from single cells of three donors were cloned, sequenced, and expressed as recombinant hmAbs. Of 26 cloned H chain Ab genes, 22 were IgA and 4 were IgM. The genes were highly mutated, and there was an overrepresentation of the VH4 family. Of 10 expressed hmAbs, 8 were rotavirus-reactive (6 with K(d) < 1 × 10(-10)). Importantly, our method allows generation of hmAbs from cells implicated in the protection of mucosal surfaces, and it can potentially be used in passive vaccination efforts and for discovery of epitopes directly relevant to human immunity. PMID:20935207

Di Niro, Roberto; Mesin, Luka; Raki, Melinda; Zheng, Nai-Ying; Lund-Johansen, Fridtjof; Lundin, Knut E A; Charpilienne, Annie; Poncet, Didier; Wilson, Patrick C; Sollid, Ludvig M

2010-11-01

260

miR-802 regulates human angiotensin II type 1 receptor expression in intestinal epithelial C2BBe1 cells.  

Science.gov (United States)

Studies have demonstrated that angiotensin II (Ang II) can regulate intestinal fluid and electrolyte transport and control intestinal wall muscular activity. Ang II is also a proinflammatory mediator that participates in inflammatory responses such as apoptosis, angiogenesis, and vascular remodeling; accumulating evidence suggests that this hormone may be involved in gastrointestinal (GI) inflammation and carcinogenesis. Ang II binds to two distinct G protein-coupled receptor subtypes, the AT(1)R and AT(2)R, which are widely expressed in the GI system. Together these studies suggest that Ang II-AT(1)R/-AT(2)R actions may play an important role in GI tract physiology and pathophysiology. Currently it is not known whether miRNAs can regulate the expression of the human AT(1)R (hAT(1)R) in the GI system. PCR and in situ hybridization experiments demonstrated that miR-802 was abundantly expressed in human colon and intestine. Luciferase reporter assays demonstrated that miR-802 could directly interact with the bioinformatics-predicted target site harbored within the 3'-untranslated region of the hAT(1)R mRNA. To validate that the levels of miR-802 were physiologically relevant in the GI system, we demonstrated that miR-802 "loss-of-function" experiments resulted in augmented hAT(1)R levels and enhanced Ang II-induced signaling in a human intestinal epithelial cell line. These results suggest that miR-802 can modulate the expression of the hAT(1)R in the GI tract and ultimately play a role in regulating the biological efficacy of Ang II in this system. PMID:20558762

Sansom, Sarah E; Nuovo, Gerard J; Martin, Mickey M; Kotha, Sainath R; Parinandi, Narasimham L; Elton, Terry S

2010-09-01

 
 
 
 
261

Indirect evidence for cholinergic inhibition of intestinal bicarbonate absorption in humans  

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BACKGROUND—The aim of the study was to test the hypothesis that in the fasting state, proximal intestinal HCO3 absorption, which depends on villus Na+/H+ exchanger activity, is tonically inhibited by a cholinergic atropine sensitive mechanism. ?SUBJECTS—The experiments were performed in 34 healthy volunteers and in eight patients with intestinal villus atrophy. ?METHODS—HCO3 absorption was measured with a modified triple lumen perfusion technique in th...

Mellander, A.; Sjovall, H.

1999-01-01

262

Identification of Hypoxia-induced Metabolic Changes in Human Intestinal Epithelial Cells  

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BACKGROUND: Inflammatory Bowel Disease (IBD) is an intestinal inflammatory process resulting in abnormal gut barrier function; reduced oxygen delivery within the epithelium has been correlated with shifts in tissue metabolism. The goal of this study was to investigate the utility of high-resolution mass spectrometry coupled with full-coverage fragmentation for analysis of metabolite changes induced by hypoxia. METHODS: T84 intestinal epithelial cells were cultured and exposed to either 24 hou...

Ladak, Adam; Kominsky, Douglas; Colgan, Sean; Jonscher, Karen

2012-01-01

263

Human intestinal epithelial cells in innate immunity : interactions with normal microbiota and pathogenic bacteria  

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Rod-shaped bacteria were previously shown to be associated with the small intestinal epithelium of children with celiac disease (CD). Using culture-dependent and independent methods, we characterized the microbiota of small intestine in children with CD and controls. The normal microbiota constitutes an unique organ-specific biofilm. Dominant bacteria are Streptococcus, Neisseria, Veillonella, Gemella, Actinomyces, Rothia and Haemophilus. Altogether 162 Genus Level Operational Taxonomic Units...

Ou, Gangwei

2009-01-01

264

Human intestinal microbiota composition is associated with local and systemic inflammation in obesity (online first)  

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OBJECTIVE: Intestinal microbiota have been suggested to contribute to the development of obesity, but the mechanism remains elusive. The relationship between microbiota composition, intestinal permeability, and inflammation in nonobese and obese subjects was investigated. DESIGN AND METHODS: Fecal microbiota composition of 28 subjects (BMI 18.6-60.3 kg m-2 ) was analyzed by a phylogenetic profiling microarray. Fecal calprotectin and plasma C-reactive protein levels were determined to e...

2013-01-01

265

Heparan sulfate and syndecan-1 are essential in maintaining murine and human intestinal epithelial barrier function  

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Patients with protein-losing enteropathy (PLE) fail to maintain intestinal epithelial barrier function and develop an excessive and potentially fatal efflux of plasma proteins. PLE occurs in ostensibly unrelated diseases, but emerging commonalities in clinical observations recently led us to identify key players in PLE pathogenesis. These include elevated IFN-?, TNF-?, venous hypertension, and the specific loss of heparan sulfate proteoglycans from the basolateral surface of intestinal epit...

2008-01-01

266

Disease-Dependent Adhesion of Lactic Acid Bacteria to the Human Intestinal Mucosa  

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Their adhesion to the intestinal mucosa is considered one of the main reasons for the beneficial health effects of specific lactic acid bacteria (LAB). However, the influence of disease on the mucosal adhesion is largely unknown. Adhesion of selected LAB to resected colonic tissue and mucus was determined in patients with three major intestinal diseases (i.e., diverticulitis, rectal carcinoma, and inflammatory bowel disease) and compared to healthy control tissue. All strains were observed to...

Ouwehand, Arthur C.; Salminen, Seppo; Roberts, Peter J.; Ovaska, Jari; Salminen, Eeva

2003-01-01

267

Small intestinal CD103+ dendritic cells display unique functional properties that are conserved between mice and humans  

DEFF Research Database (Denmark)

A functionally distinct subset of CD103(+) dendritic cells (DCs) has recently been identified in murine mesenteric lymph nodes (MLN) that induces enhanced FoxP3(+) T cell differentiation, retinoic acid receptor signaling, and gut-homing receptor (CCR9 and alpha4beta7) expression in responding T cells. We show that this function is specific to small intestinal lamina propria (SI-LP) and MLN CD103(+) DCs. CD103(+) SI-LP DCs appeared to derive from circulating DC precursors that continually seed the SI-LP. BrdU pulse-chase experiments suggested that most CD103(+) DCs do not derive from a CD103(-) SI-LP DC intermediate. The majority of CD103(+) MLN DCs appear to represent a tissue-derived migratory population that plays a central role in presenting orally derived soluble antigen to CD8(+) and CD4(+) T cells. In contrast, most CD103(-) MLN DCs appear to derive from blood precursors, and these cells could proliferate within the MLN and present systemic soluble antigen. Critically, CD103(+) DCs with similar phenotype and functional properties were present in human MLN, and their selective ability to induce CCR9 was maintained by CD103(+) MLN DCs isolated from SB Crohn's patients. Thus, small intestinal CD103(+) DCs represent a potential novel target for regulating human intestinal inflammatory responses.

Jaensson, Elin; Uronen-Hansson, Heli

2008-01-01

268

Correlation between human papillomavirus infection and bladder transitional cell carcinoma  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background To determine the association of human papillomavirus infection (HPV and transitional cell carcinoma (TCC. Methods Using polymerase chain reaction, fifty-nine bladder tissue specimens of patients with transitional cell carcinoma of bladder compared with 20 bladder samples of cases with non-neoplastic disorders. Results Male to female ratio was similar in the two groups (50/9 vs. 16/4, P = 0.62. Mean age was 67 ± 10.8 years and 52 ± 20.3 years in the case and control groups, respectively (P = 0.6. Of the 59 tissue specimens with diagnosis of transitional cell carcinoma, HPV DNA was detected in 21 (35.6% samples, while it was present in only one sample (5% in the control group (P = 0.008. HPV18 was the most common type of virus with the incidence rate of 17/21(81%. Conclusion HPV might play a causative role in transitional cell carcinoma of bladder in our geographic area.

Moghaddam SMM Hosseini

2005-11-01

269

PKQuest: measurement of intestinal absorption and first pass metabolism – application to human ethanol pharmacokinetics  

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Full Text Available Abstract Background PKQuest, a new physiologically based pharmacokinetic (PBPK program, is applied to human ethanol data. The classical definition of first pass metabolism (FPM based on the differences in the area under the curve (AUC for identical intravenous and oral doses is invalid if the metabolism is non-linear (e.g. ethanol. Uncertainties in the measurement of FPM have led to controversy about the magnitude of gastric alcohol metabolism. PKQuest implements a new, rigorous definition of FPM based on finding the equivalent intravenous input function that would produce a blood time course identical to that observed for the oral intake. This input function equals the peripheral availability (PA and the FPM is defined by: FPM = Total oral dose – PA. PKQuest also provides a quantitative measurement of the time course of intestinal absorption. Methods PKQuest was applied to previously published ethanol pharmacokinetic data. Results The rate of ethanol absorption is primarily limited by the rate of gastric emptying. For oral ethanol with a meal: absorption is slow (? 3 hours and the fractional PKQuest FPM was 36% (0.15 gm/Kg dose and 7% (0.3 gm/Kg. In contrast, fasting oral ethanol absorption is fast (? 50 minutes and FPM is small. Conclusions The standard AUC and one compartment methods significantly overestimate the FPM. Gastric ethanol metabolism is not significant. Ingestion of a coincident meal with the ethanol can reduce the peak blood level by about 4 fold at low doses. PKQuest and all the examples are freely available on the web at http://www.pkquest.com.

Levitt David G

2002-08-01

270

Human intestinal absorption of imidacloprid with Caco-2 cells as enterocyte model  

International Nuclear Information System (INIS)

In order to assess the risk to mammals of a chronic exposure to imidacloprid (IMI), we investigated its absorption with the human intestinal Caco-2 cell line. Measurements of transepithelial transport revealed an apparent permeability coefficient of 21.6 x 10-6 ± 3.2 x 10-6 cm/s reflecting a 100% absorption. The comparison of apical to basal (A-B) and basal to apical (B-A) transports showed that the monolayer presents a basal to apical polarized transport. Studies of apical uptake demonstrated that the transport was concentration-dependent and not saturable from 5 to 200 ?M. Arrhenius plot analysis revealed two apparent activation energies, Ea(4-12deg.C) = 63.8 kJ/mol and Ea(12-37deg. C) 18.2 kJ/mol, suggesting two temperature-dependent processes. IMI uptake was equivalent when it was performed at pH 6.0 or 7.4. Depletion of Na+ from the transport buffer did not affect the uptake, indicating that a sodium-dependent transporter was not involved. Decrease of uptake with sodium-azide or after cell surface trypsin (Ti) treatment suggested the involvement of a trypsin-sensitive ATP-dependent transporter. Investigations on apical efflux demonstrated that initial velocities paralleled the increase of loading concentrations. A cell surface trypsin treatment did not affect the apical efflux. The lack of effect when the efflux was performed against an IMI concentration gradient suggested that an energy-dependent transporter was involved. However, the inhibition of P-glycoproteins (P-gp) and multidrug resistance-associated proteins (MRP) by taxol, vincristine, and daunorubicine had no effect on IMI intracellular accumulation suggesting the involvement of transporters distinct from classical ATP binding cassette transport (ABC-transport) systems. All results suggest that IMI is strongly absorbed in vivo by inward and outward active transporters

2004-01-01

271

Exopolysaccharides produced by probiotic strains modify the adhesion of probiotics and enteropathogens to human intestinal mucus.  

Science.gov (United States)

Exopolysaccharides (EPSs) are exocellular polymers present in the surface of many bacteria, including Lactobacillus and Bifidobacterium. The genome sequence of several strains revealed the presence of EPS-encoding genes. However, the physiological role that EPSs play in the bacterial ecology still remains uncertain. In this study, we have assessed the effect of EPSs produced by Lactobacillus rhamnosus GG, Bifidobacterium longum NB667, and Bifidobacterium animalis IPLA-R1 on the adhesion of probiotic and enteropathogen strains to human intestinal mucus. The EPS fraction GG had no significant effect on the adhesion of L. rhamnosus GG and B. animalis IPLA-R1. However, the EPS fractions NB667 and IPLA-R1 significantly reduced the adherence of both probiotic strains. In contrast, the three EPS fractions increased the adhesion of Enterobacter sakazakii ATCC 29544 and Escherichia coli NCTC 8603. Higher adherence of Salmonella enterica serovar Typhimurium ATCC 29631 and Clostridium difficile ATCC 9689 was detected in the presence of the EPS fractions GG and NB667. In general, these effects were obtained at EPS concentrations of up to 5 mg/ml, and they were EPS dose dependent. The competitive exclusion of probiotics in the presence of EPS could suggest the involvement of these biopolymers in the adhesion to mucus. The increase in the adherence of enteropathogens could be explained if components of the pathogen surface are able to bind to specific EPSs and the bound EPSs are able to adhere to mucus. To the best of our knowledge, this is the first work reporting the effect of EPSs from probiotics on bacterial adhesion properties. PMID:16924934

Ruas-Madiedo, Patricia; Gueimonde, Miguel; Margolles, Abelardo; de los Reyes-Gavilán, Clara G; Salminen, Seppo

2006-08-01

272

In Vivo Transfer of the vanA Resistance Gene from an Enterococcus faecium Isolate of Animal Origin to an E. faecium Isolate of Human Origin in the Intestines of Human Volunteers  

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Transient colonization by vancomycin-resistant enterococci of animal origin has been documented in the intestines of humans. However, little is known about whether transfer of the vanA gene occurs in the human intestine. Six volunteers ingested a vancomycin-resistant Enterococcus faecium isolate of chicken origin, together with a vancomycin-susceptible E. faecium recipient of human origin. Transconjugants were recovered in three of six volunteers. In one volunteer, not only was vancomycin res...

Lester, Camilla H.; Frimodt-møller, Niels; Sørensen, Thomas Lund; Monnet, Dominique L.; Hammerum, Anette M.

2006-01-01

273

Dipeptide model prodrugs for the intestinal oligopeptide transporter. Affinity for and transport via hPepT1 in the human intestinal Caco-2 cell line  

DEFF Research Database (Denmark)

The human intestinal di/tri-peptide carrier, hPepT1, has been suggested as a drug delivery target via increasing the intestinal transport of low permeability compounds by designing peptidomimetic prodrugs. Model ester prodrugs using the stabilized dipeptides D-Glu-Ala and D-Asp-Ala as pro-moieties for benzyl alcohol have been shown to maintain affinity for hPepT1. The primary aim of the present study was to investigate if modifications of the benzyl alcohol model drug influence the corresponding D-Glu-Ala and D-Asp-Ala model prodrugs' affinity for hPepT1 in Caco-2 cells. A second aim was to investigate the transepithelial transport and hydrolysis parameters for D-Asp(BnO)-Ala and D-Glu(BnO)-Ala across Caco-2 cell monolayers. In the present study, all investigated D-Asp-Ala and D-Glu-Ala model prodrugs retained various degrees of affinity for hPepT1 in Caco-2 cells. These affinities are used to establish a QSAR of our benzyl alcohol modified model prodrugs, aided at elucidating the observed differences in model prodrug affinity for hPepT1; additionally, these data suggest that the hydrophobicity of the side-chain model drug is the major determinant in the compounds affinity for hPepT1. Transepithelial transport studies performed using Caco-2 cells of D-Asp(BnO)-Ala and D-Glu(BnO)-Ala showed that the K(m) for transepithelial transport was not significantly different for the two compounds. The maximal transport rate of the carrier-mediated flux component does not differ between the two model prodrugs either. The transepithelial transport of D-Asp(BnO)-Ala and D-Glu(BnO)-Ala follows simple kinetics, and the release of benzyl alcohol is pH-dependent, but unaffected by 1 mM of the esterase inhibitor Paraoxon in 80% human plasma and Caco-2 cell homogenate.

Nielsen, C U; Andersen, R

2001-01-01

274

Comparison of intestinal metabolism of CYP3A substrates between rats and humans: application of portal-systemic concentration difference method.  

Science.gov (United States)

Abstract 1.?Rats are frequently used in pharmacokinetic studies during drug discovery. However, there is limited information regarding species differences in intestinal availability (Fg) between rats and humans. 2.?Here, we directly estimated the fraction of dose absorbed in the portal vein (FaFg) of rats for nine CYP3A substrates using portal-systemic concentration difference method and compared them with human FaFg. No distinct difference in FaFg between the two species was observed, and seven of the nine compounds were within a two-fold difference. Given that their net fraction of dose absorbed (Fa) are expected to be high, this result indicates a moderate correlation in Fg between the two species. 3.?In contrast, the in vitro intrinsic clearance (CLint,u) in rat intestinal microsomes tended to be lower than that in humans, and the correlation between intestinal CLint,u and FaFg in rats was poor compared with that in humans. 4.?Our finding indicates that rats are appropriate animals for evaluation of the intestinal absorption and metabolism of CYP3A substrates. However, a degree of caution is required when estimating rat Fg from rat intestinal microsomes due to the low metabolic activity and the poor correlation between in vitro and in vivo intestinal metabolism. PMID:24329478

Kadono, Keitaro; Koakutsu, Akiko; Naritomi, Yoichi; Terashita, Shigeyuki; Tabata, Kenji; Teramura, Toshio

2014-06-01

275

Transition state structure of human 5?-methylthioadenosine phosphorylase†  

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Kinetic isotope effects (KIEs) and computer modeling using density functional theory were used to approximate the transition state of human 5?-methylthioadenosine phosphorylase (MTAP). KIEs were measured on the arsenolysis of 5?-methylthioadenosine (MTA) catalyzed by MTAP and were corrected for the forward commitment to catalysis. Intrinsic KIEs were obtained for [1?-3H], [1?-14C], [2?-3H], [4?-3H], [5?-3H], [9-15N] and [Me-3H3] MTAs. The primary intrinsic KIEs (1?-14C and 9-1...

2006-01-01

276

Geometrical guidance and trapping transition of human sperm cells  

CERN Document Server

The guidance of human sperm cells under confinement in quasi 2D microchambers is investigated using a purely physical method to control their distribution. Transport property measurements and simulations are performed with dilute sperm populations, for which effects of geometrical guidance and concentration are studied in detail. In particular, a trapping transition at convex angular wall features is identified and analyzed. We also show that highly efficient microratchets can be fabricated by using curved asymmetric obstacles to take advantage of the spermatozoa specific swimming strategy.

Guidobaldi, A; Berdakin, I; Moshchalkov, V V; Condat, C A; Marconi, V I; Giojalas, L; Silhanek, A V

2014-01-01

277

In vivo gene expression profiling of human intestinal epithelial cells: analysis by laser microdissection of formalin fixed tissues  

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Full Text Available Abstract Background The small intestinal epithelium mediates vital functions of nutrient absorption and host defense. The spatial organization of the epithelial cells along the crypt-villus axis segregates them into regions of specialized function. However, the differences in transcriptional programming and the molecular machinery that governs the migration, adhesion, and differentiation of intestinal epithelial cell lineages in humans remain under-explored. To increase our understanding of these mechanisms, we have evaluated gene expression patterns of ileal epithelial cells isolated by laser capture microdissection from either the villus epithelial or crypt cell regions of healthy human small intestinal mucosa. Expression profiles in villus and crypt epithelium were determined by DNA microarray, quantitative real-time PCR, and immunohistochemistry based methods. The expression levels of selected epithelial biomarkers were also compared between gastrointestinal tissues. Results Previously established biomarkers as well as a novel and distinct set of genes believed to be linked to epithelial cell motility, adhesion, and differentiation were found to be enriched in each of the two corresponding cell populations (GEO accession: GSE10629. Additionally, high baseline expression levels of innate antimicrobials, alpha defensin 5 (HD5 and regenerating islet-derived 3 alpha (Reg3A, were detected exclusively within the small bowel crypt, most notably in the ileum in comparison to other sites along the gastrointestinal tract. Conclusion The elucidation of differential gene expression patterns between crypt and villus epithelial cell lineages in human ileal tissue provides novel insights into the molecular machinery that mediates their functions and spatial organization. Moreover, our findings establish an important framework of knowledge for future investigations of human gastrointestinal diseases.

Sabir Sadiah

2008-05-01

278

Transcriptional response of HT-29 intestinal epithelial cells to human and bovine milk oligosaccharides.  

Science.gov (United States)

Human milk oligosaccharides (HMO) have been shown to interact directly with immune cells. However, large quantities of HMO are required for intervention or clinical studies, but these are unavailable in most cases. In this respect, bovine milk is potentially an excellent source of commercially viable analogues of these unique molecules. In the present study, we compared the transcriptional response of colonic epithelial cells (HT-29) to the entire pool of HMO and bovine colostrum oligosaccharides (BCO) to determine whether the oligosaccharides from bovine milk had effects on gene expression that were similar to those of their human counterparts. Gene set enrichment analysis of the transcriptional data revealed that there were a number of similar biological processes that may be influenced by both treatments including a response to stimulus, signalling, locomotion, and multicellular, developmental and immune system processes. For a more detailed insight into the effects of milk oligosaccharides, the effect on the expression of immune system-associated glycogenes was chosen as a case study when performing validation studies. Glycogenes in the current context are genes that are directly or indirectly regulated in the presence of glycans and/or glycoconjugates. RT-PCR analysis revealed that HMO and BCO influenced the expression of cytokines (IL-1?, IL-8, colony-stimulating factor 2 (granulocyte-macrophage) (GM-CSF2), IL-17C and platelet factor 4 (PF4)), chemokines (chemokine (C-X-C motif) ligand 1 (CXCL1), chemokine (C-X-C motif) ligand 3 (CXCL3), chemokine (C-C motif) ligand 20 (CCL20), chemokine (C-X-C motif) ligand 2 (CXCL2), chemokine (C-X-C motif) ligand 6 (CXCL6), chemokine (C-C motif) ligand 5 (CCL5), chemokine (C-X3-C motif) ligand 1 (CX3CL1) and CXCL2) and cell surface receptors (interferon ? receptor 1 (IFNGR1), intercellular adhesion molecule-1 (ICAM-1), intercellular adhesion molecule-2 (ICAM-2) and IL-10 receptor ? (IL10RA)). The present study suggests that milk oligosaccharides contribute to the development and maturation of the intestinal immune response and that bovine milk may be an attractive commercially viable source of oligosaccharides for such applications. PMID:23710626

Lane, Jonathan A; O'Callaghan, John; Carrington, Stephen D; Hickey, Rita M

2013-12-01

279

Selective antimicrobial modulation of the intestinal tract by norfloxacin in human volunteers and in gnotobiotic mice associated with a human fecal flora.  

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Intestinal endogenous members of the family Enterobacteriaceae were eliminated in 12 human volunteers treated with 400 or 800 mg of oral norfloxacin per day for 5 days. No clones resistant to quinolone derivatives were isolated. Counts of aerotolerant streptococci were affected to various degrees, depending on their susceptibility to norfloxacin. During treatment, counts of anaerobes remained above 9.8 log10 CFU/g of feces. A total of 932 anaerobic isolates from the predominant flora (over 10...

Pecquet, S.; Andremont, A.; Tancre?de, C.

1986-01-01

280

[Human infection by intestinal protozoa and helminths in Calbuco County, X Region, Chile, 1997].  

Science.gov (United States)

By the performance of parasitological examination of one fecal sample per individual, a total of 256 persons from a rural county in the X Region (41 degrees 50 minutes South lat., 73 degrees 05 minutes West long.) were studied. The general rates of infection by intestinal parasite and/or commensal protozoa and helminths found were: Giardia intestinalis 14.1%, Entamoeba histolytica 11.7%, Blastocystis hominis 36.0%, Entamoeba coli 9.8%, Endolimax nana 16.4%, Iodamoeba buetschlii 1.2%, Chilomastix mesnili 0.8%, Ascaris lumbricoides 13.7% and Trichuris trichiura 9.8%. The prevalence rates of intestinal infection led us to conclude that environmental conditions favorable for its transmission remain and show that intestinal parasitoses are still a public health problem in this region, affecting mostly children. PMID:9497539

Mercado, R; Otto, J P; Musleh, M; Pérez, M

1997-01-01

 
 
 
 
281

Blastocystis ratti Contains Cysteine Proteases That Mediate Interleukin-8 Response from Human Intestinal Epithelial Cells in an NF-?B-Dependent Manner?  

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Blastocystis is a ubiquitous enteric protozoan found in the intestinal tracts of humans and a wide range of animals. Evidence accumulated over the last decade suggests association of Blastocystis with gastrointestinal disorders involving diarrhea, abdominal pain, constipation, nausea, and fatigue. Clinical and experimental studies have associated Blastocystis with intestinal inflammation, and it has been shown that Blastocystis has potential to modulate the host immune response. Blastocystis ...

Puthia, Manoj K.; Lu, Jia; Tan, Kevin S. W.

2008-01-01

282

Characterization of In Vitro Glucuronidation Clearance of a Range of Drugs in Human Kidney Microsomes: Comparison with Liver and Intestinal Glucuronidation and Impact of Albumin  

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Previous studies have shown the importance of the addition of albumin for characterization of hepatic glucuronidation in vitro; however, no reports exist on the effects of albumin on renal or intestinal microsomal glucuronidation assays. This study characterized glucuronidation clearance (CLint, UGT) in human kidney, liver, and intestinal microsomes in the presence and absence of bovine serum albumin (BSA) for seven drugs with differential UDP-glucuronosyltransferase (UGT) 1A9 and UGT2B7 spec...

Gill, Katherine L.; Houston, J. Brian; Galetin, Aleksandra

2012-01-01

283

Anti-inflammatory effects of pomegranate (Punica granatum L.) husk ellagitannins in Caco-2 cells, an in vitro model of human intestine  

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This study aimed at evaluating the anti-inflammatory properties of a pomegranate fruit husk (PomH) polyphenolic extract, rich in punicalagin, using Caco-2 cells, an in vitro model of human intestinal epithelium. Differentiated cells in bicameral inserts were pretreated or not with a PomH extract or punicalagin, as reference, at the apical side, representing the intestinal lumen. Inflammation was then induced with a cocktail of cytokines (Il-1?, TNF? and IFN?) and LPS. After 24 h incubation...

Hollebeeck, Sylvie; Winand, Julie; Herent, Marie-france; During, Alexandrine; Quetin-leclercq, Joe?lle; Larondelle, Yvan; Schneider, Yves-jacques

2012-01-01

284

DNA–Methylome Analysis of Mouse Intestinal Adenoma Identifies a Tumour-Specific Signature That Is Partly Conserved in Human Colon Cancer  

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Aberrant CpG methylation is a universal epigenetic trait of cancer cell genomes. However, human cancer samples or cell lines preclude the investigation of epigenetic changes occurring early during tumour development. Here, we have used MeDIP-seq to analyse the DNA methylome of APCMin adenoma as a model for intestinal cancer initiation, and we present a list of more than 13,000 recurring differentially methylated regions (DMRs) characterizing intestinal adenoma of the mouse. We show that Polyc...

Grimm, Christina; Chavez, Lukas; Vilardell, Mireia; Farrall, Alexandra L.; Tierling, Sascha; Bo?hm, Julia W.; Grote, Phillip; Lienhard, Matthias; Dietrich, Jo?rn; Timmermann, Bernd; Walter, Jo?rn; Schweiger, Michal R.; Lehrach, Hans; Herwig, Ralf; Herrmann, Bernhard G.

2013-01-01

285

Intestinal Coccidia  

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Full Text Available Intestinal Coccidia are a subclass of Apicomplexa phylum. Eucoccidida are facultative heteroxenous, but some of them are monoxenous. They have sexual and asexual life cycle. Some coccidia are human pathogens, for example: Cryptosporidium: Cryptosporidiums has many species that are mammalian intestinal parasites.C. Parvum specie is a human pathogenic protozoa. Cryptosporidum has circle or ellipse shapes and nearly 4-6 mm. It is transmitted in warm seasons. Oocyst is obtained insexual life cycle that has 20% thin layer and 80% thick layer. Oocyst with thick layer is able to live a long time in nature. They are the third or forth of gastroentritis disease that have digestive disorder like anorexia, nausea, persistent diarrhoea, malabsorption and leanness. The disease forms choronic and acute stages and it is able to kill the immunodeficiency cases. Sometimes it has HIV symptoms similar to pneumonia and respiratory track infection. Laboratory diagnosis is based on Oocyst finding in stool exam and that shitter floatation and Cr (KOH2 are the best methods. Modified zyh-lnelson and fleocroum are the best staining methods too. This parasite is transmitted by zoonotic and Antroponotic origin. Molecular studies have shown two Genotypes (I&II. Genotype I is aquatic and II is zoonotic. The prevalence rate is 3% in infants and 10% in calves. Cyclospora: This parasite is novel and is bigger than cryptosporidium.It isn't known a clear life cycle but is transmitted by water, vegetables and fruits as raspberries. and mulberries. Human is a specific host. When a parasite is in the intestine it causes inflammatory reaction in Entrocyte.The patient shows watery diarrhoea with nausea, vomitting, pain, Stomach cramp, anorexia, malabsorption and cachexia. The disease period is 3 monthes in immunodeficiency cases but it is selflimited in normal cases. Autofluorescence characteristic is differential diagnosis, prevalence rate of disease is unknown. Isospora: This intestinal parasite is in most parts of the world. Sometimes it is noun traveller diarrhea Syndrom. The egg shapes of Oocyst are disporic tetrazoic. It is transmitted by vegetables and fruits. Trophozoite pass through schizogony step and repeats it several times. In the end of the cycle gametogony is done and the sexual forms will be repelled the human intestine. Symptoms are persistent diarrhoea, epigastric pain, headache, fever, vomitting and leanness, especially when physiologic disorder condition is seen in patient or they are in traveling. Misdiagnosis is a problem in laboratories but floatation method with zinc sulfate or sugar syrup is recommended. Sarcocystis: Sporocyst of S.hominis and S. suihominis is in the human feces, and the cyst form is in pig and cow muscles. It founds in tha tongue, pharynx and oesophagus muscles of habitant buffalo in Iran. Because of the large size of the cyst (1cm, it is seen with naked eyes and the risk of human infection is rare. If human eats raw or uncooked cow and pig meat, he will be infected with it. Sexual cycle is in the human body and sporocyst is repelled by the intestine. The disease may or may not have any symptoms. The symptoms are diarrhoea, stomach cramp, jejenuom and ileum necrosis. Diagnosis is based on concentrated floatation. The prevalence rate is too much in domestic animals.

MJ Ggaravi

2007-06-01

286

Ontogeny of Human Hepatic and Intestinal Transporter Gene Expression during Childhood: Age Matters.  

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Many drugs prescribed to children are drug transporter substrates. Drug transporters are membrane-bound proteins that mediate the cellular uptake or efflux of drugs and are important to drug absorption and elimination. Very limited data are available on the effect of age on transporter expression. Our study assessed age-related gene expression of hepatic and intestinal drug transporters. Multidrug resistance protein 2 (MRP2), organic anion transporting polypeptide 1B1 (OATP1B1), and OATP1B3 expression was determined in postmortem liver samples (fetal n = 6, neonatal n = 19, infant n = 7, child n = 2, adult n = 11) and multidrug resistance 1 (MDR1) expression in 61 pediatric liver samples. Intestinal expression of MDR1, MRP2, and OATP2B1 was determined in surgical small bowel samples (neonates n = 15, infants n = 3, adults n = 14). Using real-time reverse-transcription polymerase chain reaction, we measured fetal and pediatric gene expression relative to 18S rRNA (liver) and villin (intestines), and we compared it with adults using the 2(-??Ct) method. Hepatic expression of MRP2, OATP1B1, and OATP1B3 in all pediatric age groups was significantly lower than in adults. Hepatic MDR1 mRNA expression in fetuses, neonates, and infants was significantly lower than in adults. Neonatal intestinal expressions of MDR1 and MRP2 were comparable to those in adults. Intestinal OATP2B1 expression in neonates was significantly higher than in adults. We provide new data that show organ- and transporter-dependent differences in hepatic and intestinal drug transporter expression in an age-dependent fashion. This suggests that substrate drug absorption mediated by these transporters may be subject to age-related variation in a transporter dependent pattern. PMID:24829289

Mooij, Miriam G; Schwarz, Ute I; de Koning, Barbara A E; Leeder, J Steven; Gaedigk, Roger; Samsom, Janneke N; Spaans, Edwin; van Goudoever, Johannes B; Tibboel, Dick; Kim, Richard B; de Wildt, Saskia N

2014-08-01

287

Intestinal invagination Invaginación intestinal.  

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Full Text Available Intestinal intussusceptions are the most frequent cause of acute surgical occlusive syndrome in infants; it is idiopathic in more than 90% of cases. Their treatment can be conservative, with reduction by means of imaging and hydrostatic procedures, or surgical. We presented the Good Clinical Practices Guideline for Intestinal intussusceptions, approved by consensus in the 3th National Good Clinical Practices Workshop in Pediatric Surgery (Camagüey, Cuba; February 23 – 26, 2004.
La invaginación intestinal es la causa más frecuente del síndrome de abdomen agudo quirúrgico oclusivo en lactantes y es idiopática en más del 90 % de los casos. Su tratamiento puede ser conservador, con reducción mediante procedimientos hidrostáticos combinados con vigilancia imaginológica, o quirúrgico. Se presenta la Guía de Buenas Prácticas Clínicas para invaginación intestinal, aprobada por consenso en el 3er Taller Nacional de Buenas Prácticas Clínicas en Cirugía Pediátrica (Camagüey, 23 al 26 de febrero de 2004.

Dayamnelys Aguilar Atanay

288

Intestinal Obstruction  

Science.gov (United States)

An intestinal obstruction occurs when food or stool cannot move through the intestines. The obstruction can be complete or partial. ... abdomen Inability to pass gas Constipation A complete intestinal obstruction is a medical emergency. It often requires surgery. ...

289

Intestinal invagination Invaginación intestinal.  

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Intestinal intussusceptions are the most frequent cause of acute surgical occlusive syndrome in infants; it is idiopathic in more than 90% of cases. Their treatment can be conservative, with reduction by means of imaging and hydrostatic procedures, or surgical. We presented the Good Clinical Practices Guideline for Intestinal intussusceptions, approved by consensus in the 3th National Good Clinical Practices Workshop in Pediatric Surgery (Camagüey, Cuba; February 23 – 26, 2004).

2005-01-01

290

Pro-inflammatory flagellin proteins of prevalent motile commensal bacteria are variably abundant in the intestinal microbiome of elderly humans.  

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Some Eubacterium and Roseburia species are among the most prevalent motile bacteria present in the intestinal microbiota of healthy adults. These flagellate species contribute "cell motility" category genes to the intestinal microbiome and flagellin proteins to the intestinal proteome. We reviewed and revised the annotation of motility genes in the genomes of six Eubacterium and Roseburia species that occur in the human intestinal microbiota and examined their respective locus organization by comparative genomics. Motility gene order was generally conserved across these loci. Five of these species harbored multiple genes for predicted flagellins. Flagellin proteins were isolated from R. inulinivorans strain A2-194 and from E. rectale strains A1-86 and M104/1. The amino-termini sequences of the R. inulinivorans and E. rectale A1-86 proteins were almost identical. These protein preparations stimulated secretion of interleukin-8 (IL-8) from human intestinal epithelial cell lines, suggesting that these flagellins were pro-inflammatory. Flagellins from the other four species were predicted to be pro-inflammatory on the basis of alignment to the consensus sequence of pro-inflammatory flagellins from the ?- and ?- proteobacteria. Many fliC genes were deduced to be under the control of ?(28). The relative abundance of the target Eubacterium and Roseburia species varied across shotgun metagenomes from 27 elderly individuals. Genes involved in the flagellum biogenesis pathways of these species were variably abundant in these metagenomes, suggesting that the current depth of coverage used for metagenomic sequencing (3.13-4.79 Gb total sequence in our study) insufficiently captures the functional diversity of genomes present at low (?1%) relative abundance. E. rectale and R. inulinivorans thus appear to synthesize complex flagella composed of flagellin proteins that stimulate IL-8 production. A greater depth of sequencing, improved evenness of sequencing and improved metagenome assembly from short reads will be required to facilitate in silico analyses of complete complex biochemical pathways for low-abundance target species from shotgun metagenomes. PMID:23935906

Neville, B Anne; Sheridan, Paul O; Harris, Hugh M B; Coughlan, Simone; Flint, Harry J; Duncan, Sylvia H; Jeffery, Ian B; Claesson, Marcus J; Ross, R Paul; Scott, Karen P; O'Toole, Paul W

2013-01-01

291

Ginsenoside-mediated blockade of 1?,25-dihydroxyvitamin D3 inactivation in human liver and intestine in vitro.  

Science.gov (United States)

The beneficial effects of vitamin D3 are exerted through 1?,25-dihydroxyvitamin D3 [1?,25(OH)2D3], the dihydroxy metabolite of vitamin D3. Hepatic and intestinal biotransformation of 1?,25(OH)2D3 and modifiers of metabolic capacity could be important determinants of bioavailability in serum and tissues. Ginsenosides and their aglycones, mainly 20(S)-protopanaxadiol (aPPD) and 20(S)-protopanaxatriol (aPPT), are routinely ingested as health supplements. The purpose of the present study was to investigate the potential of ginsenosides and their aglycones to block hepatic and intestinal inactivation of 1?,25(OH)2D3, which is the most potent ligand of vitamin D receptor. In vitro biotransformation reactions were initiated with NADPH regenerating solutions following initial preincubation of pooled human hepatic or intestinal microsomal protein or human recombinant CYP3A4 supersomes with 1?,25(OH)2D3 or midazolam. Formation of hydroxylated metabolites of 1?,25(OH)2D3 or midazolam was analyzed using liquid chromatography-mass spectrometry. Co-incubation of 1?,25(OH)2D3 with various ginsenosides (Rg1, Rh2, aPPD, aPPT and total ginsenosides) led to differential inhibition (30-100%) of its hydroxylation. Results suggest that aPPD, aPPT and Rh2 strongly attenuated the hydroxylation of 1?,25(OH)2D3. Follow up inhibition studies with aPPD and aPPT at varying concentrations (0.5-100?M) led to up to 91-100% inhibition of formation of hydroxylated metabolites of 1?,25(OH)2D3 thus preventing inactivation of active vitamin D3. The IC50 values of aPPD or aPPT for the most abundant hydroxylated metabolites of 1?,25(OH)2D3 ranged from 3.3 to 9.0?M in human microsomes. The inhibitory mechanism of aPPD or aPPT for CYP3A4-mediated biotransformation of 1?,25(OH)2D3 was competitive in nature (apparent Ki: 1.7-2.9?M). Similar inhibitory effects were also observed upon addition of aPPD or aPPT into midazolam hydroxylation assay. In summary, our results suggest that ginsenosides, specifically aPPD and aPPT, inhibit the CYP3A4-mediated catabolism of active vitamin D3 in human liver and intestine, potentially providing additional vitamin D-related benefits to patients with cancer, neurodegenerative and metabolic diseases. PMID:24486455

Deb, Subrata; Chin, Mei Yieng; Adomat, Hans; Guns, Emma S Tomlinson

2014-05-01

292

Potentiation of cytokine induced iNOS expression in the human intestinal epithelial cell line, DLD-1, by cyclic AMP  

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BACKGROUND—Nitric oxide production by the inducible isoform of nitric oxide synthase (iNOS) is thought to play a role in the pathogenesis of inflammatory bowel disease along with other proinflammatory mediators.?AIMS—To examine the effects of cAMP, an intracellular mediator of several proinflammatory mediators, on iNOS expression in the human intestinal epithelial cell line, DLD-1.?METHODS—iNOS activity was assessed by measuring the NO stable oxidative product NO2 . iNOS pro...

Cavicchi, M.; Whittle, B.

1999-01-01

293

Expression of vasoactive intestinal polypeptide and calcitonin gene-related peptide in human stellate ganglia after acute myocardial infarction.  

Science.gov (United States)

Using the method of indirect immunofluorescence the distribution of vasoactive intestinal polypeptide (VIP) and calcitonin gene-related peptide (CGRP) was investigated in autopsy specimens of human stellate ganglia following acute myocardial infarction (AMI). The dramatic increase of both VIP- and CGRP-immunoreactivities in principal ganglionic neurons as well as of calcitonin gene-related peptide in perineuronal nets was revealed. It was concluded that hypoxia and myocardial ischaemia following AMI are the main inducing factors for activation of both vasoactive regulatory neuropeptide synthesis. The upregulation of VIP and CGRP expression in sympathetic ganglionic neurons may provide regulatory and trophic support to the ischaemic heart. PMID:11508359

Roudenok, V; Gutjar, L; Antipova, V; Rogov, Y

2001-07-01

294

Transcriptional regulation of the human Na+/H+ exchanger NHE3 by serotonin in intestinal epithelial cells  

International Nuclear Information System (INIS)

Serotonin (5-HT) decreases NHE2 and NHE3 activities under acute conditions in human intestinal epithelial cells. Here, we have investigated the effects of 5-HT on expression of the human NHE3 gene and the mechanisms underlying its transcriptional regulation in differentiated C2BBe1 cells. Treatment of the human intestinal epithelial cell line, C2BBe1, with 5-HT (20 ?M) resulted in a significant decrease in NHE3 mRNA and protein expression. In transient transfection studies, 5-HT repressed the NHE3 promoter activity by ?55%. The repression of the NHE3 promoter activity in response to 5-HT was accompanied by reduced DNA-binding activity of transcription factors Sp1 and Sp3 to the NHE3 promoter without alteration in their nuclear levels. Pharmacological inhibitors of protein kinase C reversed the inhibitory effect of 5-HT on the promoter activity. Our data indicate that 5-HT suppresses the transcriptional activity of the NHE3 promoter and this effect may be mediated by PKC? and modulation of DNA-binding affinities of Sp1 and Sp3.

2009-05-08

295

Transcriptional regulation of the human Na+/H+ exchanger NHE3 by serotonin in intestinal epithelial cells.  

Science.gov (United States)

Serotonin (5-HT) decreases NHE2 and NHE3 activities under acute conditions in human intestinal epithelial cells. Here, we have investigated the effects of 5-HT on expression of the human NHE3 gene and the mechanisms underlying its transcriptional regulation in differentiated C2BBe1 cells. Treatment of the human intestinal epithelial cell line, C2BBe1, with 5-HT (20 microM) resulted in a significant decrease in NHE3 mRNA and protein expression. In transient transfection studies, 5-HT repressed the NHE3 promoter activity by approximately 55%. The repression of the NHE3 promoter activity in response to 5-HT was accompanied by reduced DNA-binding activity of transcription factors Sp1 and Sp3 to the NHE3 promoter without alteration in their nuclear levels. Pharmacological inhibitors of protein kinase C reversed the inhibitory effect of 5-HT on the promoter activity. Our data indicate that 5-HT suppresses the transcriptional activity of the NHE3 promoter and this effect may be mediated by PKCalpha and modulation of DNA-binding affinities of Sp1 and Sp3. PMID:19303862

Amin, Md Ruhul; Ghannad, Leda; Othman, Ahmad; Gill, Ravinder K; Dudeja, Pradeep K; Ramaswamy, Krishnamurthy; Malakooti, Jaleh

2009-05-01

296

A comparison of the efficiency of human embryo intestine, Hep 2 cells, and human embryo kidney cells for the primary isolation of ophthalmic viruses.  

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A comparison has been made of the efficiency of 3 cell systems, human embryo kidney (HEK), Hep 2, and a continuous line of human embryo intestine (HEI), for the isolation of ophthalmic viruses. A total of 40 herpes simplex, 51 adenoviruses, and 2 vaccinia viruses were isolated from 323 specimens. HEK cells were found to be the optimal system, 85 out of 93 (91%) of the viruses being detected in these cells alone. However, HEK cells are difficult to obtain, and therefore the use of a combinatio...

Cubitt, W. D.; Mcswiggan, D. A.; Thaker, U.; Darougar, S.

1981-01-01

297

Calorimetric studies of the structural transitions of the human erythrocyte membrane. Studies of the B and C transitions.  

Science.gov (United States)

Differential scanning calorimetry has been used to study several structural transitions of the human erythrocyte membrane. Earlier studies have shown that one of these transitions (the A transition) is due to the thermal unfolding of spectrin on the membrane. In this paper, it is shown that two of the other transitions (B and C) exhibit a high sensitivity to a local anesthetic, benzyl alcohol. Increasing the ionic strength of the suspending medium results in a splitting of the B transition into two indepent transitions (B1 and B2). It is found that one of these (B2) is associated with titrating groups, since the midpoint for the transitions shifts by about 20 degrees C, with an apparent pK near 7.5 Extensive bilateral proteolysis by papain causes a drastic decrease in the size of all transitions except the C transition, which remains unaltered. On the other hand, treatment with phospholipase by A2 largely affects the C transition, causing its disappearance. Because of the lack of sensitivity to proteolysis and the high sensitivity to phospholipase, it appears that the C transition has a large extent of 'lipid involvement'. It might result from the melting of a small fraction of phospholipid which exists in a crystalline state under physiological conditions. Alternatively, the C transition could arise from changes in protein-lipid interactions or from lipid-dependent changes in protein-protein interactions, providing one assumes that only protease-resistant portions of membrane proteins are participating. PMID:708733

Brandts, J F; Taverna, R D; Sadasivan, E; Lysko, K A

1978-10-01

298

The inhibitory effects of alpha(2)-adrenoceptor agonists on gastrointestinal transit during croton oil-induced intestinal inflammation.  

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1. The peripheral effects of alpha(2)-adrenoceptor agonists were investigated in a model of intestinal inflammation induced by intragastric administration of croton oil (CO). Our hypothesis was that inflammation would 'sensitize' adrenoceptors in peripheral and/or central terminals of myenteric and submucous plexus neurones, and enhance systemic effects of alpha(2)-adrenoceptor agonists. 2. Male swiss CD-1 mice, received intragastrically CO (0.05 ml), castor oil (CA, 0.1 ml) or saline (SS) 3 ...

Pol, O.; Valle, L.; Ferrer, I.; Puig, M. M.

1996-01-01

299

Sitagliptin, a DPP-4 Inhibitor, Acutely Inhibits Intestinal Lipoprotein Particle Secretion in Healthy Humans.  

Science.gov (United States)

The dipeptidyl peptidase-4 inhibitor sitagliptin, an antidiabetic agent, which lowers blood glucose levels, also reduces postprandial lipid excursion after a mixed meal. The underlying mechanism of this effect, however, is not clear. This study examined the production and clearance of triglyceride-rich lipoprotein particles from the liver and intestine in healthy volunteers in response to a single oral dose of sitagliptin. Using stable isotope tracer techniques and with control of pancreatic hormone levels, the kinetics of lipoprotein particles of intestinal and hepatic origin were measured. Compared with placebo, sitagliptin decreased intestinal lipoprotein concentration by inhibiting particle production, independent of changes in pancreatic hormones, and circulating levels of glucose and free fatty acids. Fractional clearance of particles of both intestinal and hepatic origin, and production of particles of hepatic origin, were not affected. This pleiotropic effect of sitagliptin may explain the reduction in postprandial lipemia seen in clinical trials of this agent and may provide metabolic benefits beyond lowering of glucose levels. PMID:24584549

Xiao, Changting; Dash, Satya; Morgantini, Cecilia; Patterson, Bruce W; Lewis, Gary F

2014-07-01

300

Mucin Degradation by Bifidobacterium Strains Isolated from the Human Intestinal Microbiota? †  

Science.gov (United States)

The presence of the genes engBF (endo-?-N-acetylgalactosaminidase) and afcA (1,2-?-l-fucosidase) was detected in several intestinal Bifidobacterium isolates. Two strains of Bifidobacterium bifidum contained both genes, and they were able to degrade high-molecular weight porcine mucin in vitro. The expression of both genes was highly induced in the presence of mucin.

Ruas-Madiedo, Patricia; Gueimonde, Miguel; Fernandez-Garcia, Maria; de los Reyes-Gavilan, Clara G.; Margolles, Abelardo

2008-01-01

 
 
 
 
301

Antimicrobial activity of Phyllanthus amarus on some human intestinal facultatively anaerobic flora  

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Full Text Available Background: Phyllanthus amarus is an economic plant grown in West Africa that has antimicrobial properties. Aim: We investigated antimicrobial activity of aqueous extract of Phyllanthus amarus against some intestinal flora that are facultative anaerobes. Methods: The leaves were washed thoroughly in clean water, and rinsed in sterile distilled water, allowed to dry at room temperature for several days. It was oven dried at 45OC for about an hour until considered brittle enough to bleed. Final dilutions used were 500 mg/ml, 400 mg/ml, 300 mg/ml, 250 mg/ml and 200 mg/ml. Six intestinal organisms were isolated and identified: K. pneumoniae, P. aeruginosa, S. aureus, E. coli. P. mirabilis and E. faecalis. Both agar diffusion and broth dilution methods were used to assay antimicrobial activity against the organisms. Results: The result indicated that the growth of the organisms were inhibited at 50 mg/ml of aqueous extract by agar diffusion and broth dilution methods but varied at lower concentration. Phyllanthus amarus showed bacteriostatic action at this concentration because sub-culture yielded growth except on plate of K. pneumoniae. Consumption of cold or hot aqueous herbal preparations can alter microbial balance. The implication of ingestion of cold or hot aqueous herbal preparations against the normal intestinal flora was discussed. Conclusion: P. amarus possesses significant antimicrobial activity against normal intestinal flora.

Babatunde S.K

2014-03-01

302

Human umbilical cord blood cell transplantation improves cardiac function in a myoardial infarction rat model but induces intestinal graft versus host disease.  

Science.gov (United States)

Human umbilical cord blood cell (HUCBC) has low immunity. In the present study we investigated intestinal graft—versus—host disease (GVHD) induced by HUCBC transplantation in a myocardial infarction (MI) rat model. MI was established by using left anterior descending coronary artery (LAD) ligation. HUCBCs were injected into the animals 5 days post MI. Four weeks after the HUCBC transplantation, histology changes in small intestine were observed under an optical microscope. In addition, cardiac functions were tested. Further, factor VIII, vascular endothelial growth factor (VEGF) in the myocardium and small intestine were assayed. The HUCBC transplantation significantly induced intestinal GVHD in the MI rats. The HUCBC implantation remarkably improved ejection fraction (EF), fractional shortening (FS), and dp/dtmax in the MI rats (P<0.05). In the myocardium, the capillary density was larger in the small intestine of the HUCBC—transplanted rats compared to the controls. Real—time PCR and western blotting revealed that VEGF mRNA and protein levels in the myocardium and the small intestine dramatically significantly upregulated in the HUCBC—transplanted rats (P<0.05). The HUCBC transplantation significantly improves aggravated cardiac function of MI rats, but it induces intestinal GVHD. PMID:24929007

Xing, Y; Wu, Y; Wang, L; Meng, X

2014-01-01

303

Dietary fibers affect viscosity of solutions and simulated human gastric and small intestinal digesta.  

Science.gov (United States)

Two experiments were conducted to determine the viscosities of both soluble and insoluble dietary fibers. In Expt. 1, corn bran, defatted rice bran, guar gum, gum xanthan, oat bran, psyllium, soy hulls, stabilized rice bran, wheat bran, wood cellulose, and 2 methylcellulose controls (Ticacel 42, Ticacel 43) were hydrated in water overnight at 0.5, 1, 1.5, or 2% concentrations. In Expt. 2, guar gum, oat bran, psyllium, rice bran, wheat bran, and wood cellulose were subjected to a 2-stage in vitro gastric and small intestinal digestion simulation model. Viscosity was measured every 2 and 3 h during gastric and small intestinal simulation, respectively. Viscosities in both experiments were measured at multiple shear rates. Viscosities of all fiber solutions were concentration- and shear rate-dependent. Rice brans, soy hulls, and wood cellulose had the lowest viscosities, whereas guar gum, psyllium, and xanthan gum had the highest viscosities, regardless of concentration. During gastric simulation, viscosity was higher (P < 0.05) at 4 h than at 0 h for guar gum, psyllium, rice bran, and wheat bran. During small intestinal simulation, viscosities were higher (P < 0.05) between 3 and 9 h compared with 18 h for guar gum, oat bran, and rice bran. Guar gum, psyllium, and oat bran exhibited viscous characteristics throughout small intestinal simulation, indicating potential for these fibers to elicit blood glucose and lipid attenuation. Wheat and rice brans and wood cellulose did not exhibit viscous characteristics throughout small intestinal digestion; thus, they may be beneficial for laxation. PMID:16549450

Dikeman, Cheryl L; Murphy, Michael R; Fahey, George C

2006-04-01

304

Mouse gastric tumor models with prostaglandin E2 pathway activation show similar gene expression profiles to intestinal-type human gastric cancer  

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Full Text Available Abstract Background Gastric cancers are generally classified into better differentiated intestinal-type tumor and poorly differentiated diffuse-type one according to Lauren's histological categorization. Although induction of prostaglandin E2 pathway promotes gastric tumors in mice in cooperation with deregulated Wnt or BMP signalings, it has remained unresolved whether the gastric tumor mouse models recapitulate either of human gastric cancer type. This study assessed the similarity in expression profiling between gastric tumors of transgenic mice and various tissues of human cancers to find best-fit human tumors for the transgenic mice models. Results Global expression profiling initially found gastric tumors from COX-2/mPGES-1 (C2mE-related transgenic mice (K19-C2mE, K19-Wnt1/C2mE, and K19-Nog/C2mE resembled gastric cancers among the several tissues of human cancers including colon, breast, lung and gastric tumors. Next, classification of the C2mE-related transgenic mice by a gene signature to distinguish human intestinal- and diffuse-type tumors showed C2mE-related transgenic mice were more similar to intestinal-type compared with diffuse one. We finally revealed that induction of Wnt pathway cooperating with the prostaglandin E2 pathway in mice (K19-Wnt1/C2mE mice further reproduce features of human gastric intestinal-type tumors. Conclusion We demonstrated that C2mE-related transgenic mice show significant similarity to intestinal-type gastric cancer when analyzed by global expression profiling. These results suggest that the C2mE-related transgenic mice, especially K19-Wnt1/C2mE mice, serve as a best-fit model to study molecular mechanism underlying the tumorigenesis of human gastric intestinal-type cancers.

Oshima Masanobu

2009-12-01

305

Detection of human intestinal catalase-negative, Gram-positive cocci by rRNA-targeted reverse transcription-PCR.  

Science.gov (United States)

An analytical system based on rRNA-targeted reverse transcription-quantitative PCR (RT-qPCR) for enumeration of catalase-negative, Gram-positive cocci was established. Subgroup- or species-specific primer sets targeting 16S or 23S rRNA from Enterococcus, Streptococcus, and Lactococcus were newly developed. The RT-qPCR method using these primers together with the previously reported primer sets specific for the Enterococcus genus, the Streptococcus genus, and several Streptococcus species was found to be able to quantify the target populations with detection limits of 10(3) to 10(4) cells per gram feces, which was more than 100 times as sensitive as the qPCR method (10(6) to 10(8) cells per gram feces). The RT-qPCR analysis of fecal samples from 24 healthy adult volunteers using the genus-specific primer sets revealed that Enterococcus and Streptococcus were present as intestinal commensals at population levels of log(10) 6.2 +/- 1.4 and 7.5 +/- 0.9 per gram feces (mean +/- standard deviation [SD]), respectively. Detailed investigation using species- or subgroup-specific primer sets revealed that the volunteers harbored unique Enterococcus species, including the E. avium subgroup, the E. faecium subgroup, E. faecalis, the E. casseliflavus subgroup, and E. caccae, while the dominant human intestinal Streptococcus species was found to be S. salivarius. Various Lactococcus species, such as L. lactis subsp. lactis or L. lactis subsp. cremoris, L. garvieae, L. piscium, and L. plantarum, were also detected but at a lower population level (log(10) 4.6 +/- 1.2 per gram feces) and prevalence (33%). These results suggest that the RT-qPCR method enables the accurate and sensitive enumeration of human intestinal subdominant but still important populations, such as Gram-positive cocci. PMID:20581195

Kubota, Hiroyuki; Tsuji, Hirokazu; Matsuda, Kazunori; Kurakawa, Takashi; Asahara, Takashi; Nomoto, Koji

2010-08-01

306

Identification of human cytochrome P450 enzymes involved in the hepatic and intestinal biotransformation of 20(S)-protopanaxadiol.  

Science.gov (United States)

20(S)-Protopanaxadiol (aPPD), a ginseng sapogenin, has been shown to be a promising anti-cancer compound and anti-depressant agent. Although the bacterial biotransformation of ginsenosides has been studied thoroughly, few have reported on the cytochrome P450 (P450) mediated metabolism of aPPD. Taken orally, aPPD must first undergo absorption and metabolism in the intestine before further metabolism in the liver. The present study investigated the comparative biotransformation profile of aPPD in human intestinal microsomes (HIM) and human liver microsomes (HLM) and characterized the human P450 enzymes involved in aPPD metabolism. Three major monooxygenated metabolites and five minor dioxygenated metabolites were identified as the predominant products in aPPD incubations with HIM and HLM using liquid chromatography-mass spectrometry. Reaction phenotyping studies were performed with a panel of specific P450 chemical inhibitors, antibody inhibition and human recombinant P450 enzymes. Ketoconazole, a CYP3A inhibitor, blocked the formation of oxygenated metabolites of aPPD in both HIM and HLM in a concentration dependent manner. Among the human recombinant P450 enzymes assayed, CYP3A4 exhibited the highest activity towards aPPD oxidative metabolite formation, followed by CYP3A5. In summary, the results have shown that aPPD is extensively metabolized by HIM and the metabolite profile following in vitro incubations is similar in HIM and HLM. CYP3A4 and CYP3A5 isoforms are the predominant enzymes responsible for oxygenation of aPPD in HIM and HLM. The characterization of aPPD as a CYP3A substrate may facilitate better prediction of drug-herb interactions when aPPD is taken concomitantly with other therapeutic agents. PMID:24151189

Chiu, Nga Ting Colette; Tomlinson Guns, Emma S; Adomat, Hans; Jia, William; Deb, Subrata

2014-03-01

307

Oxidative damage and transforming growth factor beta 1 expression in pretumoral and tumoral lesions of human intestine.  

Science.gov (United States)

The aim of this study was to evaluate a possible relationship between oxidative stress and transforming growth factor beta 1 (TGF beta 1) expression in human colon adenocarcinoma. Crohn's disease, an inflammatory pathology of the intestine often regarded to as precancerous, was also examined. Indices of impaired redox balance were monitored in blood and in bioptic samples from 10 adult patients with adenocarcinoma of the colon and from five patients with Crohn's disease. On tissue samples TGF beta 1 mRNA expression was also determined. Ten healthy adults provided normal reference values for plasma indices of oxidative stress, and normal tissue distant from the lesions was used for comparative analysis. Fluorescent adducts with plasma proteins of malonaldehyde (MDA) and 4-hydroxynonenal (HNE) were significantly lower than controls in the plasma from cancer patients and significantly higher in the plasma from Crohn's patients. In adenocarcinoma biopsies, susceptibility to lipid peroxidation processes and TGF beta 1 expression were below the relative control; in Crohn's disease, lipid peroxidation and cytokine expression were both above the relative control. The findings obtained suggest the existence of an association between oxidative damage and fibrogenic cytokine expression in the human intestine. Further studies are needed to conclusively prove the correlation between the two events. PMID:9119258

Chiarpotto, E; Scavazza, A; Leonarduzzi, G; Camandola, S; Biasi, F; Teggia, P M; Garavoglia, M; Robecchi, A; Roncari, A; Poli, G

1997-01-01

308

Study on human intestinal bacterium Blautia sp. AUH-JLD56 for the conversion of arctigenin to (-)-3'-desmethylarctigenin.  

Science.gov (United States)

Arctium lappa L. (A. lappa) is a popularly used vegetable as well as herbal medicine. Human intestinal microflora was reported to convert arctiin, the lignan compound with highest content in the dried fruits of Arctium lappa, to a series of metabolites. However, the specific bacterium responsible for the formation of 3'-desmethylarctigenin (3'-DMAG), the most predominant metabolite of arctiin by rat or human intestinal microflora, has not been isolated yet. In the present study, we isolated one single bacterium, which we named Blautia sp. AUH-JLD56, capable of solely biotransforming arctiin or arctigenin to (-)-3'-DMAG. The structure of the metabolite 3'-DMAG was elucidated by electrospray ionization mass spectrometry (ESI-MS) and (1)H and (13)C nuclear magnetic resonance spectroscopy. The biotransforming kinetics and maximum biotransforming capacity of strain AUH-JLD56 was investigated. In addition, the metabolite 3'-DMAG showed significantly higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity than that of the substrate arctigenin at the concentrations tested. PMID:24236649

Liu, Ming-Yue; Li, Meng; Wang, Xiu-Ling; Liu, Peng; Hao, Qing-Hong; Yu, Xiu-Mei

2013-12-11

309

Comparative effects of the immediate and the extended release formulations of ciprofloxacin on normal human intestinal microflora.  

Science.gov (United States)

Ciprofloxacin is a well-known fluoroquinolone, active in vitro against most Gram-negative and Gram-positive bacteria. The purpose of the present study was to evaluate the ecological effects of an orally administered extended-release formulation of ciprofloxacin in comparison with an immediate-release formulation of ciprofloxacin on the normal human intestinal microflora. Thirty-six healthy female subjects were included in the study. the extended-release formulation of ciprofloxacin was given as 500 mg once daily and the immediate-release formulation as 250 mg twice daily. The treatment period was 3 days. the microbiological investigation was blinded with respect to treatment. Mean fecal concentration in the volunteers receiving the extended-release formulation ciprofloxacin was 453 mg/kg and in the immediate-release formulation ciprofloxacin volunteers, the mean fecal concentration was 392 mg/kg. The numbers of Escherichia coli were significantly suppressed while the enterococci decreased moderately in both treatment groups. No toxigenic Clostridium difficile strains were found. No major differences were observed between the two studied formulations on the normal human intestinal microflora. PMID:21742583

Rashid, M; Weintraub, A; Nord, C E

2011-06-01

310

Metabolism of constituents in Huangqin-Tang, a prescription in traditional Chinese medicine, by human intestinal flora.  

Science.gov (United States)

In the course of studies on the metabolism of active components of Huangqin-Tang by human intestinal flora (HIF), Huangqin-Tang and all individual herbs in the decoctions were incubated with a human fecal suspension separately. By using a high-performance liquid chromatographic (HPLC) method which was previously established in our laboratory, the metabolites in both the compound prescription and all the single herb decoctions were identified and determined both qualitatively and quantitatively. We found that the constituents of Huangqin-Tang, incluing baicalin (baicalein 7-glucuronide; BG), wogonoside (wogoninoglucuronide; WG), oroxylin-A-glucuronide (OG) from Scutellariae Radix, paeoniflorin (PF) from Paeoniae Radix, liquiritin (liquiritigenin 4'-O-glucoside; LG), isoliquirtin (isoliquiritigenin 4-glucoside; ILG) and glycyrrhizic acid (GL) from Glycyhhizea Radix, were converted to their metabolites baicalein (B), wogonin (W), oroxylin-A (O), paeonimetabolin-I (PM-I), liquiritigenin (L), isoliquiritigenin (IL) and glycyrrhetinic acid (GA) by HIF. The contents of the metabolites in Huangqin-Tang and in each single herb decoction increased significantly after incubation with intestinal flora. Comparing with single herb decoctions, the transformation of BG, WG, OG, LG and ILG in the compound prescription was promoted, however, that of PF and GL was inhibited. All the results suggested that the glycosides of many medicinal herbs could be converted to aglycones by HIF, and the metabolism of most glycosides was improved in the compound prescription. PMID:12033492

Zuo, Feng; Zhou, Zhong-Ming; Yan, Mei-Zhen; Liu, Mei-Lan; Xiong, Yu-Lan; Zhang, Qing; Song, Hong-Yue; Ye, Wen-Hua

2002-05-01

311

Cyanidin-3-Glucoside Suppresses Cytokine-Induced Inflammatory Response in Human Intestinal Cells: Comparison with 5-Aminosalicylic Acid  

Science.gov (United States)

The potential use of polyphenols in the prevention and treatment of chronic inflammatory diseases has been extensively investigated although the mechanisms involved in cellular signaling need to be further elucidated. Cyanidin-3-glucoside is a typical anthocyanin of many pigmented fruits and vegetables widespread in the human diet. In the present study, the protection afforded by cyanidin-3-glucoside against cytokine-triggered inflammatory response was evaluated in the human intestinal HT-29 cell line, in comparison with 5-aminosalicylic acid, a well-established anti-inflammatory drug, used in inflammatory bowel disease. For this purpose, some key inflammatory mediators and inflammatory enzymes were examined. Our data showed that cyanidin-3-glucoside reduced cytokine-induced inflammation in intestinal cells, in terms of NO, PGE2 and IL-8 production and of iNOS and COX-2 expressions, at a much lower concentration than 5-aminosalicylic acid, suggesting a higher anti-inflammatory efficiency. Interestingly, cyanidin-3-glucoside and 5-aminosalicylic acid neither prevented IkB-? degradation nor the activation of NF-kB, but significantly reduced cytokine-induced levels of activated STAT1 accumulated in the cell nucleus. In addition, we established that phosphorylated p38 MAPK was not involved in the protective effect of cyanidin-3-glucoside or 5-aminosalicylic acid. Taking into account the high concentrations of dietary anthocyanins potentially reached in the gastrointestinal tract, cyanidin-3-glucoside may be envisaged as a promising nutraceutical giving complementary benefits in the context of inflammatory bowel disease.

Serra, Diana; Paixao, Joana; Nunes, Carla; Dinis, Teresa C. P.; Almeida, Leonor M.

2013-01-01

312

Phase transitions in human IgG solutions  

Science.gov (United States)

Protein condensations, such as crystallization, liquid-liquid phase separation, aggregation, and gelation, have been observed in concentrated antibody solutions under various solution conditions. While most IgG antibodies are quite soluble, a few outliers can undergo condensation under physiological conditions. Condensation of IgGs can cause serious consequences in some human diseases and in biopharmaceutical formulations. The phase transitions underlying protein condensations in concentrated IgG solutions is also of fundamental interest for the understanding of the phase behavior of non-spherical protein molecules. Due to the high solubility of generic IgGs, the phase behavior of IgG solutions has not yet been well studied. In this work, we present an experimental approach to study IgG solutions in which the phase transitions are hidden below the freezing point of the solution. Using this method, we have investigated liquid-liquid phase separation of six human myeloma IgGs and two recombinant pharmaceutical human IgGs. We have also studied the relation between crystallization and liquid-liquid phase separation of two human cryoglobulin IgGs. Our experimental results reveal several important features of the generic phase behavior of IgG solutions: (1) the shape of the coexistence curve is similar for all IgGs but quite different from that of quasi-spherical proteins; (2) all IgGs have critical points located at roughly the same protein concentration at ~100 mg/ml while their critical temperatures vary significantly; and (3) the liquid-liquid phase separation in IgG solutions is metastable with respect to crystallization. These features of phase behavior of IgG solutions reflect the fact that all IgGs have nearly identical molecular geometry but quite diverse net inter-protein interaction energies. This work provides a foundation for further experimental and theoretical studies of the phase behavior of generic IgGs as well as outliers with large propensity to condense. The investigation of the phase diagram of IgG solutions is of great importance for the understanding of immunoglobulin deposition diseases as well as for the understanding of the colloidal stability of IgG pharmaceutical formulations.

Wang, Ying; Lomakin, Aleksey; Latypov, Ramil F.; Laubach, Jacob P.; Hideshima, Teru; Richardson, Paul G.; Munshi, Nikhil C.; Anderson, Kenneth C.; Benedek, George B.

2013-09-01

313

Phase transitions in human IgG solutions.  

Science.gov (United States)

Protein condensations, such as crystallization, liquid-liquid phase separation, aggregation, and gelation, have been observed in concentrated antibody solutions under various solution conditions. While most IgG antibodies are quite soluble, a few outliers can undergo condensation under physiological conditions. Condensation of IgGs can cause serious consequences in some human diseases and in biopharmaceutical formulations. The phase transitions underlying protein condensations in concentrated IgG solutions is also of fundamental interest for the understanding of the phase behavior of non-spherical protein molecules. Due to the high solubility of generic IgGs, the phase behavior of IgG solutions has not yet been well studied. In this work, we present an experimental approach to study IgG solutions in which the phase transitions are hidden below the freezing point of the solution. Using this method, we have investigated liquid-liquid phase separation of six human myeloma IgGs and two recombinant pharmaceutical human IgGs. We have also studied the relation between crystallization and liquid-liquid phase separation of two human cryoglobulin IgGs. Our experimental results reveal several important features of the generic phase behavior of IgG solutions: (1) the shape of the coexistence curve is similar for all IgGs but quite different from that of quasi-spherical proteins; (2) all IgGs have critical points located at roughly the same protein concentration at ~100 mg/ml while their critical temperatures vary significantly; and (3) the liquid-liquid phase separation in IgG solutions is metastable with respect to crystallization. These features of phase behavior of IgG solutions reflect the fact that all IgGs have nearly identical molecular geometry but quite diverse net inter-protein interaction energies. This work provides a foundation for further experimental and theoretical studies of the phase behavior of generic IgGs as well as outliers with large propensity to condense. The investigation of the phase diagram of IgG solutions is of great importance for the understanding of immunoglobulin deposition diseases as well as for the understanding of the colloidal stability of IgG pharmaceutical formulations. PMID:24089716

Wang, Ying; Lomakin, Aleksey; Latypov, Ramil F; Laubach, Jacob P; Hideshima, Teru; Richardson, Paul G; Munshi, Nikhil C; Anderson, Kenneth C; Benedek, George B

2013-09-28

314

Isquemia intestinal / Intestinal ischemia  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish La isquemia intestinal está considerada como la causa más letal del síndrome de abdomen agudo; su consecuencia, el infarto del intestino delgado, ocurre por fenómenos tromboembólicos e isquemia no oclusiva. El objetivo del presente artículo es proporcionar una revisión bibliográfica actualizada acer [...] ca del tema y facilitar la actuación del cirujano ante este problema de salud de repercusión sistémica y que no es tan infrecuente como se piensa Abstract in english The intestinal ischemia is considered as the most lethal cause in the acute abdomen syndrome; its consequence, the small intestine infarction, takes place due to thromboembolic phenomena and non occlusive ischemia. The objective of the present work is to provide an updated literature review about th [...] e topic and to facilitate the surgeon's performance in front of this health problem of systemic repercussion which is not as uncommon as it is thought

Ileana, Guerra Macías; Zenén, Rodríguez Fernández.

315

Pilot study of diet and microbiota: interactive associations of fibers and polyphenols with human intestinal bacteria.  

Science.gov (United States)

Several studies have addressed the use of dietary fibers in the modulation of intestinal microbiota; however, information about other highly correlated components in foods, such as polyphenols, is scarce. The aim of this work was to explore the association between the intake of fibers and polyphenols from a regular diet and fecal microbiota composition in 38 healthy adults. Food intake was recorded using an annual food frequency questionnaire (FFQ). Quantification of microbial populations in feces was performed by quantitative PCR. A negative association was found between the intake of pectins and flavanones from oranges and the levels of Blautia coccoides and Clostridium leptum. By contrast, white bread, providing hemicellulose and resistant starch, was directly associated with Lactobacillus. Because some effects on intestinal microbiota attributed to isolated fibers or polyphenols might be modified by other components present in the same food, future research should be focused on diet rather than individual compounds. PMID:24877654

Cuervo, Adriana; Valdés, Lorena; Salazar, Nuria; de Los Reyes-Gavilán, Clara G; Ruas-Madiedo, Patricia; Gueimonde, Miguel; González, Sonia

2014-06-11

316

Inhibition of the NF-?B Pathway in Human Intestinal Epithelial Cells by Commensal Streptococcus salivarius ? †  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Streptococcus salivarius exhibited an anti-inflammatory effect on intestinal epithelial cells (IECs) and monocytes. Strains were screened using a reporter clone, HT-29/kB-luc-E, induced by tumor necrosis factor alpha (TNF-?). Supernatant from each strain downregulated NF-?B activation. The two most efficient strains produced an active metabolite (<3 kDa) which was able to downregulate the secretion of the proinflammatory chemokine interleukin-8 (IL-8).

Kaci, Ghalia; Lakhdari, Omar; Dore?, Joe?l; Ehrlich, S. Dusko; Renault, Pierre; Blottie?re, Herve? M.; Delorme, Christine

2011-01-01

317

MUC-2 human small intestinal mucin gene structure. Repeated arrays and polymorphism.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

MUC-2, the first described intestinal mucin gene, has become important as a prototype for secreted mucins in several organ systems. However, little is known about its protein backbone structure and hence its role in diseases such as colon cancer, ulcerative colitis, and cystic fibrosis, which are known to have mucin abnormalities. Studies in this manuscript show that MUC-2 contains two distinct regions with a high degree of internal homology, but the two regions bear no significant homology t...

Toribara, N. W.; Gum, J. R.; Culhane, P. J.; Lagace, R. E.; Hicks, J. W.; Petersen, G. M.; Kim, Y. S.

1991-01-01

318

Adherence of Giardia lamblia trophozoites to Int-407 human intestinal cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Attachment of Giardia lamblia trophozoites to enterocytes is essential for colonization of the small intestine and is considered a prerequisite for parasite-induced enterocyte dysfunction and clinical disease. In this work, coincubation of Giardia with Int-407 cells, was used as an in vitro model to study the role of cytoskeleton and surface lectins involved in the attachment of the parasite. This interaction was also studied by scanning and transmission electron microscopy. Adherence was dep...

Sousa, M. Ce?u; Gonc?alves, C. A.; Bairos, V. A.; Poiares-da-silva, J.

2001-01-01

319

Human intestinal P-glycoprotein activity estimated by the model substrate digoxin  

DEFF Research Database (Denmark)

P-glycoprotein (Pgp) plays a part in the intestinal uptake of xenobiotics and has been associated with susceptibility to ulcerative colitis. The aim of this study was to examine Pgp activity in relation to age, gender, medical treatment (rifampicin or ketoconazole) and the multidrug resistance (MDR1) gene single nucleotide polymorphisms (SNPs) G2677T and C3435T using the model drug digoxin.

Larsen, U L; Hyldahl Olesen, L

2007-01-01

320

The Effect of Rifampin Treatment on Intestinal Expression of Human MRP Transporters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The importance of the ATP-dependent transporter P-glycoprotein, which is expressed in the brush border membrane of enterocytes and in other tissues with excretory function, for overall drug disposition is well recognized. For example, induction of intestinal P-glycoprotein by rifampin appears to be the underlying mechanism of decreased plasma concentrations of P-glycoprotein substrates such as digoxin with concomitant rifampin therapy. The contribution of transporter proteins other than P-gly...

Fromm, Martin F.; Kauffmann, Hans-martin; Fritz, Peter; Burk, Oliver; Kroemer, Heyo K.; Warzok, Rolf W.; Eichelbaum, Michel; Siegmund, Werner; Schrenk, Dieter

2000-01-01

 
 
 
 
321

Conversion of 5-fluorocytosine to 5-fluorouracil by human intestinal microflora.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mechanism of toxicity from 5-fluorocytosine chemotherapy is unclear. However, recent evidence suggests that the generation of 5-fluorouracil by a host may play an important role in the development of this toxicity. Using an in vitro semicontinuous culture system to mimic the intestinal microflora, we examined the capacity of this complex microbial community to convert 5-fluorocytosine to 5-fluorouracil. The system was dosed initially and after 2 weeks of chronic exposure to 5-fluorocytosi...

Harris, B. E.; Manning, B. W.; Federle, T. W.; Diasio, R. B.

1986-01-01

322

Effect of Metals on ?-Actin and Total Protein Synthesis in Cultured Human Intestinal Epithelial Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

As an important structural protein, ?-actin is associated with anchoring of tight junctions (TJs) to the cell scaffold. Caco-2 cells, an immortal intestinal epithelial cell line, rely on ?-actin to form intact monolayers with high transepithelial electrical resistance in cell culture inserts. We examined the effect of six metals on expression of ?-actin mRNA and ?-actin synthesis, on total and net production of newly synthesized proteins, on paracellular transport of TJ markers, and on ce...

Calabro, Anthony R.; Gazarian, Dmitry I.; Barile, Frank A.

2011-01-01

323

PUMA-mediated intestinal epithelial apoptosis contributes to ulcerative colitis in humans and mice  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Intestinal epithelial cell (IEC) apoptosis contributes to the development of ulcerative colitis (UC), an inflammatory bowel disease (IBD) that affects the colon and rectum. Therapies that target the inflammatory cytokine TNF have been found to inhibit IEC apoptosis in patients with IBD, although the mechanism of IEC apoptosis remains unclear. We therefore investigated the role of p53-upregulated modulator of apoptosis (PUMA), a p53 target and proapoptotic BH3-only protein, in colitis and IEC ...

2011-01-01

324

Effect of broad-spectrum parenteral antibiotics on composition of intestinal microflora of humans.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We compared the effects of four beta-lactam drugs with widely differing antibacterial and pharmacological properties on the composition of the intestinal flora. Cefoxitin, piperacillin, cefoperazone, and aztreonam were given intravenously for 9 days to healthy volunteers. Cefoperazone reduced the numbers of aerobic and anaerobic bacteria to undetectable levels. At the other extreme, cefoxitin had little effect on the normal flora. Aztreonam markedly reduced the numbers of aerobes, whereas pip...

Giuliano, M.; Barza, M.; Jacobus, N. V.; Gorbach, S. L.

1987-01-01

325

Human Intestinal Lumen and Mucosa-Associated Microbiota in Patients with Colorectal Cancer  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Recent reports have suggested the involvement of gut microbiota in the progression of colorectal cancer (CRC). We utilized pyrosequencing based analysis of 16S rRNA genes to determine the overall structure of microbiota in patients with colorectal cancer and healthy controls; we investigated microbiota of the intestinal lumen, the cancerous tissue and matched noncancerous normal tissue. Moreover, we investigated the mucosa-adherent microbial composition using rectal swab samples because the s...

2012-01-01

326

Adherence of Probiotic Bacteria to Human Intestinal Mucus in Healthy Infants and during Rotavirus Infection  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The concentration of fecal mucin and the adhesion of specific probiotics and their combinations in the intestinal mucus of infants during and after rotavirus diarrhea and in healthy children were determined. Mucus was prepared from fecal samples from 20 infants during and after rotavirus diarrhea and from 10 healthy age-matched children. Mucin concentration was determined, and the adhesion of five probiotics—Lactobacillus rhamnosus GG, Lactobacillus casei Shirota, Lactobacillus paracasei F1...

Juntunen, M.; Kirjavainen, P. V.; Ouwehand, A. C.; Salminen, S. J.; Isolauri, E.

2001-01-01

327

Expression and function of the lipocalin-2 (24p3/NGAL) receptor in rodent and human intestinal epithelia  

DEFF Research Database (Denmark)

The lipocalin 2//NGAL/24p3 receptor (NGAL-R/24p3-R) is expressed in rodent distal nephron where it mediates protein endocytosis. The mechanisms of apical endocytosis and transcytosis of proteins and peptides in the intestine are poorly understood. In the present study, the expression and localization of rodent 24p3-R (r24p3-R) and human NGAL-R (hNGAL-R) was investigated in intestinal segments by immunofluorescence and confocal laser scanning microscopy, immunohistochemistry and immunoblotting. r24p3-R/hNGAL-R was also studied in human Caco-2 BBE cells and CHO cells transiently transfected with r24p3-R by immunofluorescence microscopy, RT-PCR and immunoblotting of plasma membrane enriched vesicles (PM). To assay function, endocytosis/transcytosis of putative ligands phytochelatin (PCâ??), metallothionein (MT) and transferrin (Tf) was assayed by measuring internalization of fluorescence-labelled ligands in Caco-2 BBE cells grown on plastic or as monolayers on Transwell inserts. The binding affinity of Alexa 488-PCâ?? to colon-like Caco-2 BBE PM was quantified by microscale thermophoresis (MST). r24p3-R/hNGAL-R expression was detected apically in all intestinal segments but showed the highest expression in ileum and colon. Colon-like, but not duodenum-like, Caco-2 BBE cells expressed hNGAL-R on their surface. Colon-like Caco-2 BBE cells or r24p3-R transfected CHO cells internalized fluorescence-labelled PCâ?? or MT with half-maximal saturation at submicromolar concentrations. Uptake of PCâ?? and MT (0.7 µM) by Caco-2 BBE cells was partially blocked by hNGAL (500 pM) and an ECâ??â?? of 18.6 ± 12.2 nM was determined for binding of Alexa 488-PCâ?? to PM vesicles by MST. Transwell experiments showed rapid (0.5-2 h) apical uptake and basolateral delivery of fluorescent PCâ??/MT/Tf (0.7 µM). Apical uptake of ligands was significantly blocked by 500 pM hNGAL. hNGAL-R dependent uptake was more prominent with MT but transcytosis efficiency was reduced compared to PCâ?? and Tf. Hence, r24p3-R/hNGAL-R may represent a high-affinity multi-ligand receptor for apical internalization and transcytosis of intact proteins/peptides by the lower intestine.

Langelueddecke, Christian; Roussa, Eleni

2013-01-01

328

[Blastocystosis and other intestinal protozoan infections in human riverside communities of the Valdivia River basin, Chile].  

Science.gov (United States)

Between March and October 1987, the prevalence of infection by Blastocystis hominis and other intestinal protozoan, their relationship with the age and sex of the hosts, and the percentage of infected persons in family groups were determined in riverside communities of Valdivia River Basin, Chile. One or more intestinal protozoan species were determined in 72.5% of the examined persons. The prevalence was greater for B. hominis (61.8%). The prevalences of B. hominis, Endolimax nana and Entamoeba coli were greater in relation to the age of the host. The sex of the host and prevalence of infections by B. hominis and other species of intestinal protozoans did not show association. Prevalence of B. hominis was greater in persons from houses with no sanitary faeces disposal. Over 60% of the members of family groups showed infection by B. hominis in 53.1% of the groups compared to 2.4%-21.8% of infections by other protozoan species. Faecal samples of 45 pigs revealed 22.2% of infection by Blastocystis. PMID:1342125

Torres, P; Miranda, J C; Flores, L; Riquelme, J; Franjola, R; Pérez, J; Auad, S; Hermosilla, C; Riquelme, S

1992-01-01

329

Polarity of fatty acid uptake and metabolism in a human intestinal cell line (CACO-2)  

International Nuclear Information System (INIS)

Free fatty acids (ffa) can enter the intestinal cell via the apical (AP) or basolateral (BL) membrane. The authors are using the Caco-2 intestinal cell line to examine the polarity of ffa uptake and metabolism in the enterocyte. Cells are grown on permeable polycarbonate Transwell filters in order to obtain access to both AP and BL compartments. Differentiated Caco-2 cells form tight polarized monolayers which express small intestine-specific enzymes and are impermeable to the fluid phase marker Lucifer Yellow. Submicellar concentrations of 3H-palmitic acid (2uM) were added to AP or BL sides of Caco-2 monolayers at 37 degrees C and cells were incubated for various times between 2 and 120 minutes. Total AP and BL uptake is similar; however, when relative membrane surface areas are accounted for, AP uptake is about 2-fold higher. The metabolism of AP and BL ffa is not significantly different: triacylglycerol and phosphatidylcholine account for most of the metabolites (32±4 and 24±2% respectively at 5 minutes). Little ffa oxidation is observed. Preincubation with albumin-bound 2-monoolein (100uM) and palmitate (50uM) increases the level of TG metabolites. The results suggest that in this cell line the uptake of AP ffa may be greater than BL ffa, but that AP (dietary) ffa and BL (plasma) ffa are metabolized similarly

1990-02-26

330

Polarity of fatty acid uptake and metabolism in a human intestinal cell line (CACO-2)  

Energy Technology Data Exchange (ETDEWEB)

Free fatty acids (ffa) can enter the intestinal cell via the apical (AP) or basolateral (BL) membrane. The authors are using the Caco-2 intestinal cell line to examine the polarity of ffa uptake and metabolism in the enterocyte. Cells are grown on permeable polycarbonate Transwell filters in order to obtain access to both AP and BL compartments. Differentiated Caco-2 cells form tight polarized monolayers which express small intestine-specific enzymes and are impermeable to the fluid phase marker Lucifer Yellow. Submicellar concentrations of {sup 3}H-palmitic acid (2uM) were added to AP or BL sides of Caco-2 monolayers at 37{degrees}C and cells were incubated for various times between 2 and 120 minutes. Total AP and BL uptake is similar; however, when relative membrane surface areas are accounted for, AP uptake is about 2-fold higher. The metabolism of AP and BL ffa is not significantly different: triacylglycerol and phosphatidylcholine account for most of the metabolites (32{plus minus}4 and 24{plus minus}2% respectively at 5 minutes). Little ffa oxidation is observed. Preincubation with albumin-bound 2-monoolein (100uM) and palmitate (50uM) increases the level of TG metabolites. The results suggest that in this cell line the uptake of AP ffa may be greater than BL ffa, but that AP (dietary) ffa and BL (plasma) ffa are metabolized similarly.

Trotter, P.J.; Storch, J. (Harvard School of Public Health, Boston, MA (United States))

1990-02-26

331

Stability of Related Human and Chicken Campylobacter jejuni Genotypes after Passage through Chick Intestine Studied by Pulsed-Field Gel Electrophoresis  

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The genomic stability of 12 Campylobacter jejuni strains consisting of two groups of human and chicken isolates was studied by analysis of their PFGE (pulsed-field gel electrophoresis) patterns after passage through newly hatched chicks’ intestines. The patterns of SmaI, SalI, and SacII digests remained stable after intestinal passage, except for those of two strains. One originally human strain, FB 6371, changed its genotype from II/A (SmaI/SacII) to I/B. Another strain, BTI, originally is...

Ha?nninen, Marja-liisa; Hakkinen, Marjaana; Rautelin, Hilpi

1999-01-01

332

Insulin-like growth factor-binding protein-5 stimulates growth of human intestinal muscle cells by activation of G?i3  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In human intestinal smooth muscle cells, endogenous insulin-like growth factor-I (IGF-I) regulates growth and IGF-binding protein-5 (IGFBP-5) expression. The effects of IGF-I are facilitated by IGFBP-5. We previously showed that IGFBP-5 acts independently of IGF-I in human intestinal muscle to stimulate proliferation and upregulate IGF-I production by activation of Erk1/2 and p38 MAPK. Thus a positive feedback loop exists between IGF-I and IGFBP-5, whereby both stimulate muscle growth and pro...

Flynn, Robert S.; Mahavadi, Sunila; Murthy, Karnam S.; Kellum, John M.; Kuemmerle, John F.

2009-01-01

333

Effects of zinc on epithelial barrier properties and viability in a human and a porcine intestinal cell culture model.  

Science.gov (United States)

Zinc is an essential trace element with a variety of physiological and biochemical functions. Piglets are commonly supplemented, during the weaning period, with doses of zinc above dietary requirements with positive effects on health and performance that might be attributed to anti-secretory and barrier-enhancing effects in the intestine. For a better understanding of these observations increasing zinc sulfate (ZnSO4; 0-200?M) concentrations were used in an in vitro culture model of porcine (IPEC-J2) and human (Caco-2) intestinal epithelial cells and effects on barrier function, viability, and the mRNA expression of one selected heat shock protein (Hsp) were assessed. When treated apically with zinc sulfate, the transepithelial electrical resistance (TEER) did not change significantly. In contrast, cell viability measured by lactate dehydrogenase (LDH) leakage, by ATP and by WST-1 conversion in postconfluent IPEC-J2 monolayers was affected after a 24-h treatment with 200?M ZnSO4. Caco-2 cells were more resistant to Zn. ZnSO4 did not induce any effect on viability, except when it was used at the highest concentration (200?M), and only in preconfluent cells. Furthermore, ZnSO4 induced Hsp70 mRNA expression at 200?M and was more pronounced in preconfluent cells. The observed dose-related effects of zinc are cell-line specific and depended on the differentiation status of the cells. The IPEC-J2 cell line appears to be a suitable in vitro model to characterize specific effects on porcine intestinal cells. PMID:23274768

Lodemann, U; Einspanier, R; Scharfen, F; Martens, H; Bondzio, A

2013-03-01

334

Interaction of PHM, PHI and 24-glutamine PHI with human VIP receptors from colonic epithelium: comparison with rat intestinal receptors  

International Nuclear Information System (INIS)

PHM, the human counterpart of porcine Peptide Histidine Isoleucine amide (PHI), is shown to be a VIP agonist with low potency on human VIP receptors located in colonic epithelial cell membranes. Its potency is identical to that of PHI but by 3 orders of magnitude lower than that of VIP itself in inhibiting "1"2"5I-VIP binding and in stimulating adenylate cyclase activity. This contrasts markedly with the behavior of PHI on rat VIP receptors located in intestinal epithelial cell membranes where PHI is a potent agonist with a potency that is 1/5 that of VIP. In another connection, the authors show that 24-glutamine PHI has the same affinity as 24-glutamic acid PHI (the natural peptide) for rat or human VIP receptors. These results indicate that while PHI may exert some physiological function through its interaction with VIP receptors in rodents, its human counterpart PHM is a very poor agonist of VIP in human. Furthermore, they show that the drastic change in position 24 of PHI (neutral versus acid residue) does not affect the activity of PHI, at least on VIP receptors. 21 references, 1 figure

1985-03-11

335

Analysis of the human intestinal epithelial cell transcriptional response to Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium lactis and Escherichia coli  

DEFF Research Database (Denmark)

The complex microbial population residing in the human gastrointestinal tract consists of commensal, potential pathogenic and beneficial species, which are probably perceived differently by the host and consequently could be expected to trigger specific transcriptional responses. In this study, a comparative analysis of the global in vitro transcriptional response of human intestinal epithelial cells to Lactobacillus acidophilus NCFMTM, L. salivarius Ls-33, Bifidobacterium animalis subsp. lactis 420 and enterohaemorrhagic Escherichia coli O157:H7 (EHEC) was conducted. Of particular note, L. salivarius Ls-33 DCE-induced changes were overall more similar to those of B. lactis 420 than to L. acidophilus NCFMTM, which was consistent with previously observed in vivo immunomodulation properties. In gene ontology and pathway analyses, both specific and unspecific changes were observed. Common to all was the regulation of apoptosis and adipogenesis, and lipid metabolism related regulation by the probiotics. Specific changes, such as regulation of cell-cell adhesion by B. lactis 420, superoxide metabolism by L. salivarius Ls-33 and regulation of MAPK pathway by L. acidophilus NCFMTM, were noted. Furthermore, fundamental differences were observed between the pathogenic and probiotic treatments in the Toll-like receptor pathway, especially for adapter molecules with a lowered level of transcriptional activation of MyD88, TRIF, IRAK1 and TRAF6 by probiotics compared to EHEC. Results provided insights into the relationship between probiotics and human intestinal epithelial cells, notably with regard to strain-specific responses, and highlighted the differences between transcriptional responses to pathogenic and probiotic bacteria. Keyword: Epithelial cells,Microarray,Probiotics,Escherichia coli,Cell line models

Putaala, H.; Barrangou, R.

2010-01-01

336

Analysis of the human intestinal epithelial cell transcriptional response to Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium lactis and Escherichia coli.  

Science.gov (United States)

The complex microbial population residing in the human gastrointestinal tract consists of commensal, potential pathogenic and beneficial species, which are probably perceived differently by the host and consequently could be expected to trigger specific transcriptional responses. Here, we provide a comparative analysis of the global in vitro transcriptional response of human intestinal epithelial cells to Lactobacillus acidophilus NCFM™, Lactobacillus salivarius Ls-33, Bifidobacterium animalis subsp. lactis 420, and enterohaemorrhagic Escherichia coli O157:H7 (EHEC). Interestingly, L. salivarius Ls-33 DCE-induced changes were overall more similar to those of B. lactis 420 than to L. acidophilus NCFM™, which is consistent with previously observed in vivo immunomodulation properties. In the gene ontology and pathway analyses both specific and unspecific changes were observed. Common to all was the regulation of apoptosis and adipogenesis, and lipid-metabolism related regulation by the probiotics. Specific changes such as regulation of cell-cell adhesion by B. lactis 420, superoxide metabolism by L. salivarius Ls-33, and regulation of MAPK pathway by L. acidophilus NCFM™ were noted. Furthermore, fundamental differences were observed between the pathogenic and probiotic treatments in the Toll-like receptor pathway, especially for adapter molecules with a lowered level of transcriptional activation of MyD88, TRIF, IRAK1 and TRAF6 by probiotics compared to EHEC. The results in this study provide insights into the relationship between probiotics and human intestinal epithelial cells, notably with regard to strain-specific responses, and highlight the differences between transcriptional responses to pathogenic and probiotic bacteria. PMID:21831765

Putaala, H; Barrangou, R; Leyer, G J; Ouwehand, A C; Hansen, E Bech; Romero, D A; Rautonen, N

2010-09-01

337

Hes1 promotes the IL-22-mediated antimicrobial response by enhancing STAT3-dependent transcription in human intestinal epithelial cells  

Energy Technology Data Exchange (ETDEWEB)

Highlights: •Hes1 enhances IL-22-STAT3 signaling in human intestinal epithelial cells. •Hes1 enhances REG family gene induction by IL-22-STAT3 signaling. •Protein level of Hes1 restricts the response to IL-22. •Present regulation of a cytokine signal represents a new mode of Hes1 function. -- Abstract: Notch signaling plays an essential role in the proliferation and differentiation of intestinal epithelial cells (IECs). We have previously shown that Notch signaling is up-regulated in the inflamed mucosa of ulcerative colitis (UC) and thereby plays an indispensable role in tissue regeneration. Here we show that in addition to Notch signaling, STAT3 signaling is highly activated in the inflamed mucosa of UC. Forced expression of the Notch target gene Hes1 dramatically enhanced the IL-22-mediated STAT3-dependent transcription in human IECs. This enhancement of STAT3-dependent transcription was achieved by the extended phosphorylation of STAT3 by Hes1. Microarray analysis revealed that Hes1-mediated enhancement of IL-22-STAT3 signaling significantly increased the induction of genes encoding antimicrobial peptides, such as REG1A, REG3A and REG3G, in human IECs. Conversely, the reduction of Hes1 protein levels with a ?-secretase inhibitor significantly down-regulated the induction of those genes in IECs, resulting in a markedly poor response to IL-22. Our present findings identify a new role for the molecular function of Hes1 in which the protein can interact with cytokine signals and regulate the immune response of IECs.

Murano, Tatsuro [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Okamoto, Ryuichi, E-mail: rokamoto.gast@tmd.ac.jp [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Department of Advanced GI Therapeutics, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Ito, Go; Nakata, Toru; Hibiya, Shuji; Shimizu, Hiromichi; Fujii, Satoru; Kano, Yoshihito; Mizutani, Tomohiro; Yui, Shiro; Akiyama-Morio, Junko; Nemoto, Yasuhiro [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Tsuchiya, Kiichiro; Nakamura, Tetsuya [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Department of Advanced GI Therapeutics, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Watanabe, Mamoru [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan)

2014-01-17

338

Hes1 promotes the IL-22-mediated antimicrobial response by enhancing STAT3-dependent transcription in human intestinal epithelial cells  

International Nuclear Information System (INIS)

Highlights: •Hes1 enhances IL-22-STAT3 signaling in human intestinal epithelial cells. •Hes1 enhances REG family gene induction by IL-22-STAT3 signaling. •Protein level of Hes1 restricts the response to IL-22. •Present regulation of a cytokine signal represents a new mode of Hes1 function. -- Abstract: Notch signaling plays an essential role in the proliferation and differentiation of intestinal epithelial cells (IECs). We have previously shown that Notch signaling is up-regulated in the inflamed mucosa of ulcerative colitis (UC) and thereby plays an indispensable role in tissue regeneration. Here we show that in addition to Notch signaling, STAT3 signaling is highly activated in the inflamed mucosa of UC. Forced expression of the Notch target gene Hes1 dramatically enhanced the IL-22-mediated STAT3-dependent transcription in human IECs. This enhancement of STAT3-dependent transcription was achieved by the extended phosphorylation of STAT3 by Hes1. Microarray analysis revealed that Hes1-mediated enhancement of IL-22-STAT3 signaling significantly increased the induction of genes encoding antimicrobial peptides, such as REG1A, REG3A and REG3G, in human IECs. Conversely, the reduction of Hes1 protein levels with a ?-secretase inhibitor significantly down-regulated the induction of those genes in IECs, resulting in a markedly poor response to IL-22. Our present findings identify a new role for the molecular function of Hes1 in which the protein can interact with cytokine signals and regulate the immune response of IECs

2014-01-17

339

Absorção intestinal de D-xilose em crianças infectadas pelo vírus da imunodeficiência humana Intestinal absorption of D-xilose in children infected with the human immunodeficiency virus  

Directory of Open Access Journals (Sweden)

Full Text Available Objetivos - Avaliar a absorção intestinal em crianças de 18 meses a 14 anos infectadas pelo HIV, atendidas em uma unidade de ambulatório e verificar se existe associação entre má absorção, diarréia, estado nutricional, alteração imunológica, parasitas entéricos clássicos e Cryptosporidium. Metodologia - A absorção intestinal foi investigada utilizando-se a medida da D-xilose sérica. Amostras fecais foram colhidas para a pesquisa de pátogenos entéricos clássicos e Cryptosporidium. O tamanho da amostra foi calculado considerando a prevalência de 30% com precisão de 5% de alteração na absorção da D-xilose em crianças infectadas pelo HIV. Os procedimentos estatísticos utilizados foram: medidas descritivas, análise de correspondência múltipla e regressão logística. Resultados - Das 104 crianças estudadas, somente 8 (7,7% apresentaram o teste da D-xilose alterado e 33 (31,73% foram positivas para Cryptosporidium. A análise de correspondência múltipla aplicada aos dados encontrados sugeriu a associação entre o teste da D-xilose alterado e a presença de Cryptosporidium. Não se encontrou associação entre o teste alterado e diarréia, estado nutricional, alteração imunológica e parasistas entéricos clássicos. Conclusões - A má absorção intestinal avaliada pelo teste da D-xilose foi infreqüente nas crianças HIV positivas estudadas. O comprometimento intestinal, quando presente, parece estar relacionado com a presença de Cryptosporidium, porém não com diarréia, estado nutricional, alteração imunológica e parasistas entéricos clássicos.Aim - To evaluate the intestinal absorption in HIV-infected children children 14 months to 14 years and to investigate its relationship to diarrhea, nutritional status, immune dysfunction, classical enteric parasites and Cryptosporidium. Methods - Intestinal absorption was investigated by measuring serum D-xylose. Fecal samples were investigated for classical pathogens and Cryptosporidium. The sample size was calculated considering a 30% prevalence of altered D-xylose absorption in HIV-infected children with a 5% accuracy. Statistical procedures used were: descriptive measurements, multiple correspondence analysis and logistic regression. Results - D-xylose absorption was altered in only 8 out of 104 (7,7% and Cryptosporidium was positive in 33 out of 104 (31,73% HIV-infected children. The multiple correspondence analysis suggested an association between an altered D-xylose test and Cryptosporidium. D-xylose malabsorption was not associated with diarrhea, nutritional status, immune disfunction and classic enteric parasites. Conclusions - Intestinal malabsorption evaluated through the D-xylose test was an uncommon finding in HIV-infected children. Intestinal dysfunction when present seems to be related to Cryptosporidium, but not to diarrhea, nutritional status, immune disfunction and classic enteric parasites.

Nilza Medeiros PERIN

2001-10-01

340

Absorção intestinal de D-xilose em crianças infectadas pelo vírus da imunodeficiência humana / Intestinal absorption of D-xilose in children infected with the human immunodeficiency virus  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Objetivos - Avaliar a absorção intestinal em crianças de 18 meses a 14 anos infectadas pelo HIV, atendidas em uma unidade de ambulatório e verificar se existe associação entre má absorção, diarréia, estado nutricional, alteração imunológica, parasitas entéricos clássicos e Cryptosporidium. Metodolog [...] ia - A absorção intestinal foi investigada utilizando-se a medida da D-xilose sérica. Amostras fecais foram colhidas para a pesquisa de pátogenos entéricos clássicos e Cryptosporidium. O tamanho da amostra foi calculado considerando a prevalência de 30% com precisão de 5% de alteração na absorção da D-xilose em crianças infectadas pelo HIV. Os procedimentos estatísticos utilizados foram: medidas descritivas, análise de correspondência múltipla e regressão logística. Resultados - Das 104 crianças estudadas, somente 8 (7,7%) apresentaram o teste da D-xilose alterado e 33 (31,73%) foram positivas para Cryptosporidium. A análise de correspondência múltipla aplicada aos dados encontrados sugeriu a associação entre o teste da D-xilose alterado e a presença de Cryptosporidium. Não se encontrou associação entre o teste alterado e diarréia, estado nutricional, alteração imunológica e parasistas entéricos clássicos. Conclusões - A má absorção intestinal avaliada pelo teste da D-xilose foi infreqüente nas crianças HIV positivas estudadas. O comprometimento intestinal, quando presente, parece estar relacionado com a presença de Cryptosporidium, porém não com diarréia, estado nutricional, alteração imunológica e parasistas entéricos clássicos. Abstract in english Aim - To evaluate the intestinal absorption in HIV-infected children children 14 months to 14 years and to investigate its relationship to diarrhea, nutritional status, immune dysfunction, classical enteric parasites and Cryptosporidium. Methods - Intestinal absorption was investigated by measuring [...] serum D-xylose. Fecal samples were investigated for classical pathogens and Cryptosporidium. The sample size was calculated considering a 30% prevalence of altered D-xylose absorption in HIV-infected children with a 5% accuracy. Statistical procedures used were: descriptive measurements, multiple correspondence analysis and logistic regression. Results - D-xylose absorption was altered in only 8 out of 104 (7,7%) and Cryptosporidium was positive in 33 out of 104 (31,73%) HIV-infected children. The multiple correspondence analysis suggested an association between an altered D-xylose test and Cryptosporidium. D-xylose malabsorption was not associated with diarrhea, nutritional status, immune disfunction and classic enteric parasites. Conclusions - Intestinal malabsorption evaluated through the D-xylose test was an uncommon finding in HIV-infected children. Intestinal dysfunction when present seems to be related to Cryptosporidium, but not to diarrhea, nutritional status, immune disfunction and classic enteric parasites.

PERIN, Nilza Medeiros; PIRES, Maria Marlene de Souza; NASSAR, Sílvia Modesto.

 
 
 
 
341

Glycosphingolipid composition of epithelial cells isolated along the villus axis of small intestine of a single human individual.  

Science.gov (United States)

A 6-cm fresh proximal ileum surgical specimen from a blood group A(1)Le(a-b+) secretor individual was used for stepwise isolation of epithelial cells from villus tip to crypt bottom by gentle washing with ethylenediaminetetraacetic acid-containing buffer. Acid and non-acid sphingolipids were prepared from the epithelial cell fractions and the non-epithelial intestinal residue. Molecular information on the sphingolipid composition was obtained without further isolation of individual species by applying thin-layer chromatography using chemical and biological (monoclonal antibodies, cholera toxin, Escherichia coli) detection reagents, mass spectrometry and proton NMR spectroscopy of derivatized glycolipids. In this way, the structure of major and minor saccharides, ceramide components and their relative amounts were obtained. Epithelial cells and non-epithelial residue were distinctly different in their sphingolipid composition. Sphingomyelin was the major single component in both compartments. Characteristic for epithelial cells was the dominance of monoglycosylceramides, sulphatides and blood group fucolipids (mainly Le(b) hexaglycosylceramides and ALe(b) heptaglycosylceramides). The non-epithelial residue had about five times less glycolipids mainly mono-, di-, tri- and tetra-glycosylceramides and gangliosides, including the GM1 ganglioside. The ceramides were more hydroxylated (1-2 additional hydroxyls) in epithelial cell glycolipids compared with the non-epithelial residue. Combined with a separate detailed study on the glycoproteins of the same epithelial cell preparation, this human intestinal sample is the only epithelial cell preparation where both protein- and lipid-linked saccharides are characterized in detail. PMID:22833314

Breimer, Michael E; Hansson, Gunnar C; Karlsson, Karl-Anders; Larson, Göran; Leffler, Hakon

2012-12-01

342

Association between the human herpesvirus 8 and the diffuse nodular lymphoid hyperplasia of the small intestine in common variable immunodeficiency  

International Nuclear Information System (INIS)

The common variable immunodeficiency (CVID) is the more frequent primary immunodeficiency in clinical field and its presentation forms are very variable. We describe the case of a women presenting with adult CVID with chronic diarrhea syndrome, weight loss and diffuse lymphadenopathies, where the more marked immunologic features were a deep hypogammaglobulinemia of the three major kinds of immunoglobulins and numerical decrease of B cells (CD19+) and NK cells (CD3-CD56+) in peripheral blood. Biopsy of small intestine obtained by video-assisted panendoscope, showed the presence of a multinodular lymphoid hyperplasia with partial atrophy of hairinesses. Immunohistochemistry showed that nodules were high germinal centers with distribution of B cells (CD20+) and T cells (CD3+), similar to that of normal follicle. There was not differential expression of the K and ? light chains. The real time polymerase chain reaction (QRT-PCR) method detected many copies from the genome of type 8 human herpesvirus (VHH-8) (133 copies/?L of DNA) in biopsy of intestinal nodule DNA. VHH-8 infection may to be a significant factor in pathogenesis of lymphoproliferative disorders in patients presenting with CVID

2009-01-01

343

The human intestinal fatty acid binding protein (hFABP2) gene is regulated by HNF-4?  

International Nuclear Information System (INIS)

The cytosolic human intestinal fatty acid binding protein (hFABP2) is proposed to be involved in intestinal absorption of long-chain fatty acids. The aim of this study was to investigate the regulation of hFABP2 by the endodermal hepatocyte nuclear factor 4? (HNF-4?), involved in regulation of genes of fatty acid metabolism and differentiation. Electromobility shift assays demonstrated that HNF-4? binds at position -324 to -336 within the hFABP2 promoter. Mutation of this HNF-4 binding site abolished the luciferase reporter activity of hFABP2 in postconfluent Caco-2 cells. In HeLa cells, this mutation reduced the activation of the hFABP2 promoter by HNF-4? by about 50%. Thus, binding element at position -336/-324 essentially determines the transcriptional activity of promoter and may be important in control of hFABP2 expression by dietary lipids and differentiation. Studying genotype interactions of hFABP2 and HNF-4?, that are both candidate genes for diabetes type 2, may be a powerful approach

2007-04-27

344

A modular organization of the human intestinal mucosal microbiota and its association with inflammatory bowel disease.  

Science.gov (United States)

Abnormalities of the intestinal microbiota are implicated in the pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC), two spectra of inflammatory bowel disease (IBD). However, the high complexity and low inter-individual overlap of intestinal microbial composition are formidable barriers to identifying microbial taxa representing this dysbiosis. These difficulties might be overcome by an ecologic analytic strategy to identify modules of interacting bacteria (rather than individual bacteria) as quantitative reproducible features of microbial composition in normal and IBD mucosa. We sequenced 16S ribosomal RNA genes from 179 endoscopic lavage samples from different intestinal regions in 64 subjects (32 controls, 16 CD and 16 UC patients in clinical remission). CD and UC patients showed a reduction in phylogenetic diversity and shifts in microbial composition, comparable to previous studies using conventional mucosal biopsies. Analysis of weighted co-occurrence network revealed 5 microbial modules. These modules were unprecedented, as they were detectable in all individuals, and their composition and abundance was recapitulated in an independent, biopsy-based mucosal dataset 2 modules were associated with healthy, CD, or UC disease states. Imputed metagenome analysis indicated that these modules displayed distinct metabolic functionality, specifically the enrichment of oxidative response and glycan metabolism pathways relevant to host-pathogen interaction in the disease-associated modules. The highly preserved microbial modules accurately classified IBD status of individual patients during disease quiescence, suggesting that microbial dysbiosis in IBD may be an underlying disorder independent of disease activity. Microbial modules thus provide an integrative view of microbial ecology relevant to IBD. PMID:24260458

Tong, Maomeng; Li, Xiaoxiao; Wegener Parfrey, Laura; Roth, Bennett; Ippoliti, Andrew; Wei, Bo; Borneman, James; McGovern, Dermot P B; Frank, Daniel N; Li, Ellen; Horvath, Steve; Knight, Rob; Braun, Jonathan

2013-01-01

345

Grapefruit juice increases felodipine oral availability in humans by decreasing intestinal CYP3A protein expression.  

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The increase in oral availability of felodipine and other commonly used medications when taken with grapefruit juice has been assumed to be due to inhibition of CYP3A4, a cytochrome P450 that is present in liver and intestine. To evaluate the effect of repeated grapefruit juice ingestion on CYP3A4 expression, 10 healthy men were given 8 oz of grapefruit juice three times a day for 6 d. Before and after receiving grapefruit juice, small bowel and colon mucosal biopsies were obtained endoscopic...

Lown, K. S.; Bailey, D. G.; Fontana, R. J.; Janardan, S. K.; Adair, C. H.; Fortlage, L. A.; Brown, M. B.; Guo, W.; Watkins, P. B.

1997-01-01

346

The magnitude and risk factors of intestinal parasitic infection in relation to Human Immunodeficiency Virus infection and immune status, at ALERT Hospital, Addis Ababa, Ethiopia.  

Science.gov (United States)

Human Immunodeficiency Virus (HIV) and intestinal parasitic infections are among the main health problems in developing countries like Ethiopia. Particularly, co-infections of these diseases would worsen the progression of HIV to Acquired Immunodeficiency Syndrome (AIDS). The purpose of this study was to determine the magnitude and risk factors for intestinal parasites in relation to HIV infection and immune status. The study was conducted in (1) HIV positive on antiretroviral therapy (ART) and (2) ART naïve HIV positive patients, and (3) HIV-negative individuals, at All African Leprosy and Tuberculosis (TB) Eradication and Rehabilitation Training Center (ALERT) hospital in Addis Ababa, Ethiopia. Study participants were interviewed using structured questionnaires to obtain socio-demographic characteristics and assess risk factors associated with intestinal parasitic infection. Intestinal parasites were identified from fecal samples by direct wet mount, formol ether concentration, and modified Ziehl-Neelsen staining techniques. The immune status was assessed by measuring whole blood CD4 T-cell count. The overall magnitude of intestinal parasite was 35.08%. This proportion was different among study groups with 39.2% (69/176), 38.83% (40/103) and 27.14% (38/140) in ART naïve HIV positives patients, in HIV negatives, and in HIV positive on ART patients respectively. HIV positive patients on ART had significantly lower magnitude of intestinal parasitic infection compared to HIV negative individuals. Intestinal helminths were significantly lower in HIV positive on ART and ART naïve patients than HIV negatives. Low monthly income, and being married, divorced or widowed were among the socio-demographic characteristics associated with intestinal parasitic infection. No association was observed between the magnitude of intestinal parasites and CD4 T-cell count. However, Cryptosporidium parvum, and Isospora belli were exclusively identified in individuals with CD4 T-cell count of ? 350 cells/mm(3). Regular provision of mass preventive chemotherapy and extended health education will curb the burden of intestinal parasitic infection in the community. Emphasis should also be given to laboratory diagnosis and identification of opportunistic intestinal parasites in patients with lower CD4-Tcell count. PMID:24603288

Taye, Biruhalem; Desta, Kassu; Ejigu, Selamawit; Dori, Geme Urge

2014-06-01

347

DNA-methylome analysis of mouse intestinal adenoma identifies a tumour-specific signature that is partly conserved in human colon cancer.  

Science.gov (United States)

Aberrant CpG methylation is a universal epigenetic trait of cancer cell genomes. However, human cancer samples or cell lines preclude the investigation of epigenetic changes occurring early during tumour development. Here, we have used MeDIP-seq to analyse the DNA methylome of APC(Min) adenoma as a model for intestinal cancer initiation, and we present a list of more than 13,000 recurring differentially methylated regions (DMRs) characterizing intestinal adenoma of the mouse. We show that Polycomb Repressive Complex (PRC) targets are strongly enriched among hypermethylated DMRs, and several PRC2 components and DNA methyltransferases were up-regulated in adenoma. We further demonstrate by bisulfite pyrosequencing of purified cell populations that the DMR signature arises de novo in adenoma cells rather than by expansion of a pre-existing pattern in intestinal stem cells or undifferentiated crypt cells. We found that epigenetic silencing of tumour suppressors, which occurs frequently in colon cancer, was rare in adenoma. Quite strikingly, we identified a core set of DMRs, which is conserved between mouse adenoma and human colon cancer, thus possibly revealing a global panel of epigenetically modified genes for intestinal tumours. Our data allow a distinction between early conserved epigenetic alterations occurring in intestinal adenoma and late stochastic events promoting colon cancer progression, and may facilitate the selection of more specific clinical epigenetic biomarkers. PMID:23408899

Grimm, Christina; Chavez, Lukas; Vilardell, Mireia; Farrall, Alexandra L; Tierling, Sascha; Böhm, Julia W; Grote, Phillip; Lienhard, Matthias; Dietrich, Jörn; Timmermann, Bernd; Walter, Jörn; Schweiger, Michal R; Lehrach, Hans; Herwig, Ralf; Herrmann, Bernhard G; Morkel, Markus

2013-01-01

348

Absorption of 3(2H)-furanones by human intestinal epithelial Caco-2 cells.  

Science.gov (United States)

A number of 3(2H)-furanones are synthesized by fruits and have been found in cooked foodstuffs, where they impart flavor and odor because of their low perception thresholds. They show genotoxic properties in model studies but are also ranked among the antioxidants and anticarcinogens. This study examined the efficiency of intestinal absorption and metabolic conversion of 3(2H)-furanones by using Caco-2 cell monolayers as an intestinal epithelial cell model. The permeability of each agent was measured in both the apical to basal and basal to apical directions. 2,5-Dimethyl-4-methoxy-3(2H)-furanone (DMMF) showed the highest absorption rate in all experiments, while similar amounts of 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF), and 4-hydroxy-5-methyl-3(2H)-furanone (HMF) were taken up. HDMF-glucoside was almost not absorbed but was hydrolyzed to a small extent. The transport of 3(2H)-furanones could not be saturated even at levels of 500 microM and occurred in both directions. Because the uptake was only slightly reduced by apical hyperosmolarity, passive diffusion by paracellular transport is proposed. PMID:19338346

Stadler, Nicole Christina; Somoza, Veronika; Schwab, Wilfried

2009-05-13

349

Epidemiological study of human intestinal parasitosis in the Hospital of Oran (Algeria  

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Full Text Available Objective: This investigation was undertaken to evaluate the prevalence of intestinal parasitosis in patient addressed to the hospital of Oran and to identify parasites causing this infection. Design: The survey was made on 1042 individuals, external and hospitalized, having between one month and 80 years old, addressed te H.U.C. of Oran. For every patient, an analysis of stool sample was done including direct and complementary methods. Results: The prevalence is about 19,96%. Adultes (71,15% are more parasited than children (28,84%. The sex ratio is equal to 1. It is essentially Protozoa parasitism with 95,7% and Helminth represent only 4,3%. The intestinal parasites founded are : Blastocystis hominis 47,17% Entamoeba coli 18,95%, Giardia intestinalis 15,32%, Endolimax nana 5,24%, Entamoeba histolytica 4 ,83%, Pseudolimax butschlii 4,43%, Enterobius vermicularis 2,82%, Cryptosporidium sp 0,4%, Ascaris lumbricoides 0,4% and Taenia saginata 0,4%. Statistically, it was no significant to the distribution of parasites species by sex. But according to age, it was significant for Giardia intestinalis which infects more children than adults, for Endolimax nana and Blastocystis hominis with the most infection of adults. Conclusion: The majority of parasites listed are not pathological. Their epidemiology is linked to faulty hygiene; this is why developing countries are the most concerned.

A. Benouis

2013-04-01

350

Perfil epidemiológico e morbimortalidade dos pacientes submetidos à reconstrução de trânsito intestinal: experiência de um centro secundário do Nordeste Brasileiro Epidemiologic profile and morbimortality of patients undergoing reconstruction intestinal transit: experience of a secundary health service in the Northeast of Brazil  

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Full Text Available RACIONAL: A reconstrução do trânsito intestinal não está isenta de riscos cirúrgicos e apresenta taxas consideráveis de complicações pós-operatórias, sendo que a infecção continua a ser um dos maiores desafios existentes neste procedimento. OBJETIVO: Perfil epidemiológico e morbimortalidade dos pacientes submetidos à reconstrução de trânsito intestinal. MÉTODOS: Foram analisados retrospectivamente 86 prontuários de pacientes com colostomia ou ileostomia, através de fatores que tivessem impacto sobre a morbimortalidade após a reconstrução de trânsito intestinal, de janeiro de 2003 a abril de 2009. RESULTADOS: Houve 20 mulheres e 60 homens, com idade média de 43 anos. A colostomia em alça (n=34 e o trauma abdominal indicando colostomia ou ileostomia foram as condições mais frequentes. O intervalo médio entre a confecção do estoma e a reconstrução de trânsito intestinal foi 15,7 meses. O índice de morbidade foi 56,8%, sendo a infecção incisional a complicação mais comum (27.47%. A permanência hospitalar média foi 7,6 dias. Houve regressão linear positiva entre permanência hospitalar pós-operatória e a idade do paciente. Demonstrou-se associação estatisticamente significativa entre o prolongamento da permanência hospitalar e a ocorrência de complicações (pBACKGROUND: The reconstruction of the intestinal tract is not surgical complications risk-free and is associated to postoperative complications high rates; furthermore, infection remains the hardest challenge in this procedure. AIM: Epidemiological profile and mortality and morbidity in patients undergoing reconstruction of intestinal transit. METHODS: Retrospectively, 86 patients with intestinal stomas were analyzed through factors that impact on the morbimortality afterwards intestinal transit reconstruction, since January 2003 to April 2009. RESULTS: Loop colostomy (n=34 and abdominal trauma implicating 38.2% of indications to colostomy or ileostomy, were the most frequent conditions. The mean interval between stoma confection and intestinal transit reconstruction was 15.7 months. The morbidity frequency was 56.8% and incisional infection was its commonest complication (27.47%. The mean inpatient length of stay was 7.6 days. There was positive linear regression between post-operative inpatient length of stay and inpatient's age. Inpatient length of stay prolongation is associated to occurrence of complications (p<0,001. CONCLUSION: It can be inferred that the occurrence of postoperative complications and age were associated with prolonged hospital stay.

Jeany Borges e Silva

2010-09-01

351

METABOLISM OF 1-NITROPYRENE BY HUMAN, RAT, AND MOUSE INTESTINAL FLORA: NYTAGENICITY OF ISOLATED METABOLITES BY DIRECT ANALYSIS OF HPLC FRACTIONS WITH A MICROSUSPENSION REVERSE MUTATION ASSAY  

Science.gov (United States)

Among the nitro-substituted polycyclic aromatic hydrocarbons identified in environmental samples and known to be genotoxic, 1-nitropyrene is one of the most abundant. he biotransformation of 1-nitro[14C]pyrene by human, rat, and mouse intestinal microflora and the mutagenicity of...

352

Endometriosis intestinal Intestinal endometriosis  

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Full Text Available La endometriosis es un trastorno ginecológico crónico, benigno y frecuente entre las mujeres en edad fértil, estimándose que existe algún grado de endometriosis hasta en el 15% de las mujeres premenopáusicas, asociándose a historia de infertilidad, antecedente de cesárea, dismenorrea y anormalidad en el sangrado uterino. Se cree que es debida al ascenso por las trompas de Falopio de contenido menstrual (menstruación retrógrada. En la afectación intestinal, el colon es el segmento más frecuentemente afectado, sobre todo a nivel rectosigmodeo. La clínica de presentación es inespecífica, siendo lo más frecuente el dolor abdominal y/o pélvico de tipo cólico que coincide o se exacerba con la menstruación. El diagnóstico diferencial incluye la enfermedad inflamatoria intestinal, diverticulitis, colitis isquémica y procesos neoplásicos, siendo el diagnóstico definitivo anatomopatológico. En cuanto al tratamiento, éste dependerá de la clínica y de la edad de la paciente, así como de sus deseos de embarazo.Endometriosis is a chronic, benign gynaecological disorder that is frequent in women of a child-bearing age. It is estimated that there is some degree of endometriosis in as many as 15% of pre-menopausal women, associated with a history of infertility, caesarean antecedents, dysmenorrhoea and abnormality in uterine bleeding. It is believed to be due to the rise of menstrual contents through the Fallopian tubes (retrograde menstruation. In the intestinal affectation, the colon is the segment most frequently affected, above all at the rectosigmoidal level. The clinical features are unspecific, with abdominal pain the most frequent and/or pelvic pain of a cholic type that coincides with, or is exacerbated by, menstruation. Differential diagnosis includes intestinal inflammatory disease, diverticulitis, ischemic colitis and neoplastic processes, with the definitive diagnosis being anatomopathological. With respect to treatment, this will depend on the clinical features and the age of the patient, as well as her wishes with regard to pregnancy.

C.I. González

2008-08-01

353

Activation of AMP-activated protein kinase by a plant-derived dihydroisosteviol in human intestinal epithelial cell.  

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Our previous study has shown that dihydroisosteviol (DHIS), a derivative of stevioside isolated from Stevia rebaudiana (Bertoni), inhibits cystic fibrosis transmembrane conductance regulator (CFTR)-mediated transepithelial chloride secretion across monolayers of human intestinal epithelial (T84) cells and prevents cholera toxin-induced intestinal fluid secretion in mouse closed loop models. In this study, we aimed to investigate a mechanism by which DHIS inhibits CFTR activity. Apical chloride current measurements in Fisher rat thyroid cells stably transfected with wild-type human CFTR (FRT-CFTR cells) and T84 cells were used to investigate mechanism of CFTR inhibition by DHIS. In addition, effect of DHIS on AMP-activated protein kinase (AMPK) activation was investigated using Western blot analysis. Surprisingly, it was found that DHIS failed to inhibit CFTR-mediated apical chloride current in FRT-CFTR cells. In contrast, DHIS effectively inhibited CFTR-mediated apical chloride current induced by a cell permeable cAMP analog CPT-cAMP and a direct CFTR activator genistein in T84 cell monolayers. Interestingly, this inhibitory effect of DHIS on CFTR was significantly (p<0.05) reduced by pretreatment with compound C, an AMPK inhibitor. AICAR, a known AMPK activator, was able to inhibit CFTR activity in both FRT-CFTR and T84 cells. Western blot analysis showed that DHIS induced AMPK activation in T84 cells, but not in FRT-CFTR cells. Our results indicate that DHIS inhibits CFTR-mediated chloride secretion in T84 cells, in part, by activation of AMPK activity. DHIS therefore represents a novel candidate of AMPK activators. PMID:23343619

Muanprasat, Chatchai; Sirianant, Lalida; Sawasvirojwong, Sutthipong; Homvisasevongsa, Sureeporn; Suksamrarn, Apichart; Chatsudthipong, Varanuj

2013-01-01

354

Tick-Borne Encephalitis Virus Replication, Intracellular Trafficking, and Pathogenicity in Human Intestinal Caco-2 Cell Monolayers  

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Tick-borne encephalitis virus (TBEV) is one of the most important vector-borne viruses in Europe and Asia. Its transmission mainly occurs by the bite of an infected tick. However, consuming milk products from infected livestock animals caused TBEV cases. To better understand TBEV transmission via the alimentary route, we studied viral infection of human intestinal epithelial cells. Caco-2 cells were used to investigate pathological effects of TBEV infection. TBEV-infected Caco-2 monolayers showed morphological changes including cytoskeleton rearrangements and cytoplasmic vacuolization. Ultrastructural analysis revealed dilatation of the rough endoplasmic reticulum and further enlargement to TBEV containing caverns. Caco-2 monolayers maintained an intact epithelial barrier with stable transepithelial electrical resistance (TER) during early stage of infection. Concomitantly, viruses were detected in the basolateral medium, implying a transcytosis pathway. When Caco-2 cells were pre-treated with inhibitors of cellular pathways of endocytosis TBEV cell entry was efficiently blocked, suggesting that actin filaments (Cytochalasin) and microtubules (Nocodazole) are important for PI3K-dependent (LY294002) virus endocytosis. Moreover, experimental fluid uptake assay showed increased intracellular accumulation of FITC-dextran containing vesicles. Immunofluorescence microscopy revealed co-localization of TBEV with early endosome antigen-1 (EEA1) as well as with sorting nexin-5 (SNX5), pointing to macropinocytosis as trafficking mechanism. In the late phase of infection, further evidence was found for translocation of virus via the paracellular pathway. Five days after infection TER was slightly decreased. Epithelial barrier integrity was impaired due to increased epithelial apoptosis, leading to passive viral translocation. These findings illuminate pathomechanisms in TBEV infection of human intestinal epithelial cells and viral transmission via the alimentary route.

Moller, Lars; Schulzke, Joerg D.; Niedrig, Matthias; Bucker, Roland

2014-01-01

355

A comparison of the efficiency of human embryo intestine, Hep 2 cells, and human embryo kidney cells for the primary isolation of ophthalmic viruses.  

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A comparison has been made of the efficiency of 3 cell systems, human embryo kidney (HEK), Hep 2, and a continuous line of human embryo intestine (HEI), for the isolation of ophthalmic viruses. A total of 40 herpes simplex, 51 adenoviruses, and 2 vaccinia viruses were isolated from 323 specimens. HEK cells were found to be the optimal system, 85 out of 93 (91%) of the viruses being detected in these cells alone. However, HEK cells are difficult to obtain, and therefore the use of a combination of the continuous cell lines HEI and Hep 2 is recommended as an alternative. 89% of the viruses were detected by this combination. The use of either HEI or Hep 2 cells alone was unsatisfactory. PMID:6271166

Cubitt, W D; McSwiggan, D A; Thaker, U; Darougar, S

1981-08-01

356

Vasoactive intestinal polypeptide and peptide histidine methionine. Presence in human follicular fluid and effects on DNA synthesis and steroid secretion in cultured human granulosa/lutein cells.  

DEFF Research Database (Denmark)

Vasoactive intestinal polypeptide (VIP) and peptide histidine methionine (PHM) originate from the same precursor molecule, prepro VIP. In the present study we examined the concentrations of VIP and PHM in human follicular fluid and their effects on cultured human granulosa/lutein cells. Follicular fluid and cells were obtained from patients undergoing in-vitro fertilization for tubal infertility. The concentrations of VIP and PHM in pre-ovulatory human follicular fluid were measured radioimmunochemically. Granulosa/lutein cells isolated from follicular fluid were cultured under serum-free conditions with VIP and PHM in varying concentrations (0.1, 10, 1000 nmol/l). [3H]Thymidine incorporation in the cells and oestradiol as well as progesterone concentrations in the culture medium were measured. The mean (+/- SEM) concentrations of VIP and PHM were 6.8 +/- 0.1 and 7.7 +/- 0.8 pmol/l, respectively. VIP at a concentration of 10 nmol/l caused a significant increase in [3H]thymidine incorporation, and at 1000 nmol/l a significant increase in oestradiol secretion was observed. VIP had no effect on progesterone secretion. PHM at the concentrations tested did not influence any of the activities. We conclude that VIP and PHM are present in human preovulatory follicular fluid and that VIP stimulates DNA synthesis and oestradiol secretion in cultured human granulosa/lutein cells. This indicates that VIP and perhaps PHM participate in the local nervous regulation of human ovarian function.

Gräs, S; Ovesen, P

1994-01-01

357

The human neonatal small intestine has the potential for arginine synthesis; developmental changes in the expression of arginine-synthesizing and -catabolizing enzymes  

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Full Text Available Abstract Background Milk contains too little arginine for normal growth, but its precursors proline and glutamine are abundant; the small intestine of rodents and piglets produces arginine from proline during the suckling period; and parenterally fed premature human neonates frequently suffer from hypoargininemia. These findings raise the question whether the neonatal human small intestine also expresses the enzymes that enable the synthesis of arginine from proline and/or glutamine. Carbamoylphosphate synthetase (CPS, ornithine aminotransferase (OAT, argininosuccinate synthetase (ASS, arginase-1 (ARG1, arginase-2 (ARG2, and nitric-oxide synthase (NOS were visualized by semiquantitative immunohistochemistry in 89 small-intestinal specimens. Results Between 23 weeks of gestation and 3 years after birth, CPS- and ASS-protein content in enterocytes was high and then declined to reach adult levels at 5 years. OAT levels declined more gradually, whereas ARG-1 was not expressed. ARG-2 expression increased neonatally to adult levels. Neurons in the enteric plexus strongly expressed ASS, OAT, NOS1 and ARG2, while varicose nerve fibers in the circular layer of the muscularis propria stained for ASS and NOS1 only. The endothelium of small arterioles expressed ASS and NOS3, while their smooth-muscle layer expressed OAT and ARG2. Conclusion The human small intestine acquires the potential to produce arginine well before fetuses become viable outside the uterus. The perinatal human intestine therefore resembles that of rodents and pigs. Enteral ASS behaves as a typical suckling enzyme because its expression all but disappears in the putative weaning period of human infants.

Ruijter Jan M

2008-11-01

358

Significance of System L Amino Acid Transporter 1 (LAT-1) and 4F2 Heavy Chain (4F2hc) Expression in Human Developing Intestines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

To clarify the significance of expression of system L amino acid transporter 1 (LAT1) and 4F2 heavy chain (4F2hc) in the developing intestine, immunohistochemical investigation and molecular analysis were performed in the human embryonic and/or fetal intestines, ranging from 28–30 days to 34–35 weeks gestation. The molecular analysis for the expression of LAT1 and 4F2hc mRNAs was done in the pure epithelial cell samples prepared after laser assisted microdissection. The immunoreactivities...

2009-01-01

359

Inhibition of intestinal absorption and decorporation of radiocaesium in humans by hexacyanoferrates(II)  

International Nuclear Information System (INIS)

The effect of hexacyanoferrate (II) preparations, KFe[Fe(CN)6], (KFeHCF) anol Fe4[Fe(N)6 ]3, (FeHCF) on intestinal radiocaesium absorption was studied in two male volunteers. The 134Cs absorption was decreased from 100 to 3-10% when 500-1000 mg KFeHCF or FeHCF were administered 10 min before the 134Cs-labelled test meal. However, when HCF was administered simultaneously with the test meal, the 134Cs absorption was decreased to only 38-63%. The biological half-time of previously absorbed 134Cs was reduced from 106 (73) to 44 (46) days by daily administration of 3 times 0.5 g KFeHCF. The 134Cs dose conversion factors lie below the values recommended by IRCP 30, indicating that the IRCP model represents a cautious description of the Cs biokinetics in our study. (author)

1991-01-01

360

Systematic and intestinal antibody-secreting cell responses and correlates of protective immunity to human rotavirus in a gnotobiotic pig model of disease.  

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Neonatal gnotobiotic pigs orally inoculated with virulent (intestinal-suspension) Wa strain human rotavirus (which mimics human natural infection) developed diarrhea, and most pigs which recovered (87% protection rate) were immune to disease upon homologous virulent virus challenge at postinoculation day (PID) 21. Pigs inoculated with cell culture-attenuated Wa rotavirus (which mimics live oral vaccines) developed subclinical infections and seroconverted but were only partially protected agai...

Yuan, L.; Ward, L. A.; Rosen, B. I.; To, T. L.; Saif, L. J.

1996-01-01

 
 
 
 
361

Effect of Clostridium difficile toxin A on human intestinal epithelial cells: induction of interleukin 8 production and apoptosis after cell detachment.  

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Clostridium difficile is the aetiological agent of pseudomembranous colitis, and animal studies suggest the essential role of secreted toxin A in inducing disease. This study examined the biological responses to toxin A by human intestinal epithelial cells. Confluent monolayers of Caco2, HT29, and T84 cells and primary epithelial cells in organ cultures of human colonic biopsy specimens and after detachment with EDTA were studied. Interleukin 8 was assayed using enzyme linked immunosorbent as...

Mahida, Y. R.; Makh, S.; Hyde, S.; Gray, T.; Borriello, S. P.

1996-01-01

362

A third P-domain peptide gene (TFF3), human intestinal trefoil factor, maps to 21q22.3.  

Science.gov (United States)

Small peptides displaying a cysteine-rich module (termed P-domain or trefoil motif) form a recently increasing group of peptides abundantly expressed at mucosal surfaces of specific tissues and are associated with the maintenance of surface integrity. The estrogen-inducible pS2 gene (BCEI) and the human homolog to the porcine spasmolytic peptide (hsP) gene (SML1) appear synchronously expressed in healthy stomach mucosa and several carcinomas of the gastrointestinal tract. Both genes were shown to be located at 21q22.3. A new trefoil peptide from human intestinal mucosa (hITF/hP1.B) and its gene (TFF3) were described recently. By PCR analysis of a somatic cell hybrid panel and FISH using two large genomic recombinants (110 kb, 210 kb) cloned in the Bacterial Artificial Chromosome (BAC) system, we show that this gene coding for the new member of human P-domain/trefoil peptides also maps to chromosome region 21q22.3 suggesting a physical linkage of all three trefoil peptide genes. PMID:8641134

Schmitt, H; Wundrack, I; Beck, S; Gött, P; Welter, C; Shizuya, H; Simon, M I; Blin, N

1996-01-01

363

Actin reorganization is involved in vasoactive intestinal peptide induced human mast cells priming to fraktalkine-induced chemotaxis  

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Full Text Available Amr E El-ShazlyDepartment of Oto-Rhino-Laryngology and Head and Neck Surgery, Liege University Hospital (Centre hospitalier Universaitaire-C.H.U., Liege, BelgiumAbstract: We recently reported a novel neuro-immuno co-operation between vasoactive intestinal peptide (VIP and fraktalkine (FKN in recruiting human mast cells to the asthmatic airway that provided a classical example of priming effect on mast cells migratory function, but the role of the F-actin in human mast cell chemotaxis’ priming is poorly defined. Therefore the aim of this study was to further investigate the biophysical role of the cytoskeletal element; the F-actin, intracellular reorganization and its polymerization in mast cell priming of chemotaxis function. In the present communication it is shown by immunofluoresence confocal microscopy analysis that physical F-actin intracellular reorganization in a membrane bound manner on uman mast cell is involved in VIP-induced priming of human mast cell chemotaxis against FKN. The F-actin reorganization was calcium independent and without modifi cation of its contents as assessed by fluorescence-activated cell scanning analysis. These results identify a novel role for the biophysical association of F-actin in the crosstalk between neuro-inflammatory mediators and mast cells and may be an important target for therapeutic modalities in allergic inflammation.Keywords: mast cells, chemotaxis, neuroimmuno-axis, F-actin intracellular reorganization, VIP, priming

Amr E El-Shazly

2008-08-01

364

The prevalence and diversity of intestinal parasitic infections in humans and domestic animals in a rural Cambodian village.  

Science.gov (United States)

In Cambodia, intestinal parasitic infections are prevalent in humans and particularly in children. Yet, information on potentially zoonotic parasites in animal reservoir hosts is lacking. In May 2012, faecal samples from 218 humans, 94 dogs and 76 pigs were collected from 67 households in Dong village, Preah Vihear province, Cambodia. Faecal samples were examined microscopically using sodium nitrate and zinc sulphate flotation methods, the Baermann method, Koga Agar plate culture, formalin-ether concentration technique and Kato Katz technique. PCR was used to confirm hookworm, Ascaris spp., Giardia spp. and Blastocystis spp. Major gastrointestinal parasitic infections found in humans included hookworms (63.3%), Entamoeba spp. (27.1%) and Strongyloides stercoralis (24.3%). In dogs, hookworm (80.8%), Spirometra spp. (21.3%) and Strongyloides spp. (14.9%) were most commonly detected and in pigs Isospora suis (75.0%), Oesophagostomum spp. (73.7%) and Entamoeba spp. (31.6%) were found. Eleven parasite species were detected in dogs (eight helminths and three protozoa), seven of which have zoonotic potential, including hookworm, Strongyloides spp., Trichuris spp., Toxocara canis, Echinostoma spp., Giardia duodenalis and Entamoeba spp. Five of the parasite species detected in pigs also have zoonotic potential, including Ascaris spp., Trichuris spp., Capillaria spp., Balantidium coli and Entamoeba spp. Further molecular epidemiological studies will aid characterisation of parasite species and genotypes and allow further insight into the potential for zoonotic cross transmission of parasites in this community. PMID:24704609

Schär, Fabian; Inpankaew, Tawin; Traub, Rebecca J; Khieu, Virak; Dalsgaard, Anders; Chimnoi, Wissanuwat; Chhoun, Chamnan; Sok, Daream; Marti, Hanspeter; Muth, Sinuon; Odermatt, Peter

2014-08-01

365

Associations between the human intestinal microbiota, Lactobacillus rhamnosus GG and serum lipids indicated by integrated analysis of high-throughput profiling data  

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Full Text Available Accumulating evidence indicates that the intestinal microbiota regulates our physiology and metabolism. Bacteria marketed as probiotics confer health benefits that may arise from their ability to affect the microbiota. Here high-throughput screening of the intestinal microbiota was carried out and integrated with serum lipidomic profiling data to study the impact of probiotic intervention on the intestinal ecosystem, and to explore the associations between the intestinal bacteria and serum lipids. We performed a comprehensive intestinal microbiota analysis using a phylogenetic microarray before and after Lactobacillus rhamnosus GG intervention. While a specific increase in the L. rhamnosus-related bacteria was observed during the intervention, no other changes in the composition or stability of the microbiota were detected. After the intervention, lactobacilli returned to their initial levels. As previously reported, also the serum lipid profiles remained unaltered during the intervention. Based on a high-resolution microbiota analysis, intake of L. rhamnosus GG did not modify the composition of the intestinal ecosystem in healthy adults, indicating that probiotics confer their health effects by other mechanisms. The most prevailing association between the gut microbiota and lipid profiles was a strong positive correlation between uncultured phylotypes of Ruminococcus gnavus-group and polyunsaturated serum triglycerides of dietary origin. Moreover, a positive correlation was detected between serum cholesterol and Collinsella (Coriobacteriaceae. These associations identified with the spectrometric lipidome profiling were corroborated by enzymatically determined cholesterol and triglyceride levels. Actinomycetaceae correlated negatively with triglycerides of highly unsaturated fatty acids while a set of Proteobacteria showed negative correlation with ether phosphatidylcholines. Our results suggest that several members of the Firmicutes, Actinobacteria and Proteobacteria may be involved in the metabolism of dietary and endogenous lipids, and provide a scientific rationale for further human studies to explore the role of intestinal microbes in host lipid metabolism.

Willem M. de Vos

2013-02-01

366

Associations between the human intestinal microbiota, Lactobacillus rhamnosus GG and serum lipids indicated by integrated analysis of high-throughput profiling data.  

Science.gov (United States)

Accumulating evidence indicates that the intestinal microbiota regulates our physiology and metabolism. Bacteria marketed as probiotics confer health benefits that may arise from their ability to affect the microbiota. Here high-throughput screening of the intestinal microbiota was carried out and integrated with serum lipidomic profiling data to study the impact of probiotic intervention on the intestinal ecosystem, and to explore the associations between the intestinal bacteria and serum lipids. We performed a comprehensive intestinal microbiota analysis using a phylogenetic microarray before and after Lactobacillus rhamnosus GG intervention. While a specific increase in the L. rhamnosus-related bacteria was observed during the intervention, no other changes in the composition or stability of the microbiota were detected. After the intervention, lactobacilli returned to their initial levels. As previously reported, also the serum lipid profiles remained unaltered during the intervention. Based on a high-resolution microbiota analysis, intake of L. rhamnosus GG did not modify the composition of the intestinal ecosystem in healthy adults, indicating that probiotics confer their health effects by other mechanisms. The most prevailing association between the gut microbiota and lipid profiles was a strong positive correlation between uncultured phylotypes of Ruminococcus gnavus-group and polyunsaturated serum triglycerides of dietary origin. Moreover, a positive correlation was detected between serum cholesterol and Collinsella (Coriobacteriaceae). These associations identified with the spectrometric lipidome profiling were corroborated by enzymatically determined cholesterol and triglyceride levels. Actinomycetaceae correlated negatively with triglycerides of highly unsaturated fatty acids while a set of Proteobacteria showed negative correlation with ether phosphatidylcholines. Our results suggest that several members of the Firmicutes, Actinobacteria and Proteobacteria may be involved in the metabolism of dietary and endogenous lipids, and provide a scientific rationale for further human studies to explore the role of intestinal microbes in host lipid metabolism. PMID:23638368

Lahti, Leo; Salonen, Anne; Kekkonen, Riina A; Salojärvi, Jarkko; Jalanka-Tuovinen, Jonna; Palva, Airi; Oreši?, Matej; de Vos, Willem M

2013-01-01

367

Glycan-modifying bacteria-derived soluble factors from Bacteroides thetaiotaomicron and Lactobacillus casei inhibit rotavirus infection in human intestinal cells.  

Science.gov (United States)

Rotaviruses attach to intestinal cells in a process that requires glycan recognition. Some bacteria from the gut microflora have been shown to modify cell-surface glycans. In this study, human intestinal cultured cells were incubated with bacteria-derived soluble factors and infected with rotavirus. Results show that only bacterial soluble factors that increase cell-surface galactose namely, those of Bacteroides thetaiotaomicron and Lactobacillus casei were able to efficiently block rotavirus infections. Increasing cell-surface galactose using galactosyltransferase resulted in a similar blockage of rotavirus infections. These results indicate that manipulation of cell-surface intestinal glycans by bacterial soluble factors can prevent rotavirus infection in a species-specific manner, and should now be considered a potential therapeutic approach against rotavirus infection. PMID:22079149