Gas permeability
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Cíl práce: Diferenční sacharidový absorpční test se široce používá pro vyšetření střevní propustnosti. Metodou volby pro stanovení manitolu a laktulózy v moči jsou chromatografické metody (GC, HPLC). V současné době jsou dostupné komerční enzymatické testy pro stanovení těchto cukrů v moči. Srovnávali jsme výsledky plynové chromatografie a enzymatické metody. Metodika: Bylo vyšetřeno 17 vzorků moči pacientů, kteří podstoupili LAMA test, za použití plynové chromatografie a enzymatické metody na stanovení laktulózy a manitolu v moči. Výsledky těchto metod byly srovnány pomocí regrese podle Passinga-Bablocka. Výsledky: Regrese podle Passinga-Bablocka vykazuje přítomnost proporcionální odchylky, pozitivní v případě manitolu (y = 1,1994 x – 0,6512) a negativní v případě laktulózy (y = 0,8125 x – 0,0382). Patologicky zvýšená střevní propustnost byla stanovena v 6 případech GC metodou a v 5 případech enzymatickou metodou. Závěry: Mezi GC a enzymatickou metodou na stanovení manitolu a laktulózy v moči existují proporcionální odchylky. Diagnostická použitelnost obou metod byla v našem souboru pacientů srovnatelná.
Objective: Differential sugar absorption test with lactulose and mannitol is videly used for intestinal permeability investigation. The methods of choice for lactulose and mannitol determination in urine are GC and HPLC methods. At this time commercial enzymatic tests for this sugar determiantion in urine are available. We compared results of GC and enzymatic method. Methods: 17 urine samples from patients undergoing LAMA sugar absorption test were analysed by using of GC and enzymatic method for lactulose and mannitol determination. The results of these methods were compared by Passing- -Bablock regression method. Results: Passing-Bablock regression demostrates the presence of the proportional deviation, positive in case of mannitol (y = 1,1994x – 0,6512), and negative in case of lactulose (y = 0,8125x – 0,0382). Pathological increased intestinal permeability was established in 6 cases by GC method and in 5 cases by enzymatic emthod. Conclusions: The proportional deviation exists between GC and enzymatic method for lactulose and mannitol determination in urine. The diagnostic utility of both analytical methods was in our group of patients comparable.
- MeSH
- chromatografie plynová metody využití MeSH
- finanční podpora výzkumu jako téma MeSH
- klinické enzymatické testy metody využití MeSH
- laktulosa metabolismus moč MeSH
- lidé MeSH
- mannitol metabolismus moč MeSH
- permeabilita MeSH
- střevní sliznice cytologie imunologie metabolismus MeSH
- tenké střevo metabolismus mikrobiologie MeSH
- Check Tag
- lidé MeSH
- MeSH
- chromatografie plynová metody MeSH
- Crohnova nemoc komplikace patofyziologie MeSH
- disacharidy moč MeSH
- finanční podpora výzkumu jako téma MeSH
- idiopatické střevní záněty etiologie patofyziologie MeSH
- lidé MeSH
- permeabilita MeSH
- střevní sliznice fyziologie metabolismus patofyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
Composite membranes containing molecular sieve particles embedded in a polyimide matrix are promising due to their increased permeability and high selectivity in gas separation processes. Determination of permeability of dense membranes is time-consuming and the resulting values are loaded with experimental errors. The impact of uncertainty in various quantities on the reliability of the permeability values measured by the constant volume/ variable pressure method was analyzed. The total uncertainty of the measurements on polyimide/Silicalite-1 membranes is 7–13 %, the errors in membrane thickness and permeation coefficient being the main contributing factors.
BACKGROUND/AIMS: Measurement of the permeability of gut mucosa may offer a method for objective assessment of mucosal dysfunction during cancer therapy. METHODOLOGY: Gastroduodenal, intestinal and colonic permeability was studied by using capillary gas chromatography and measuring urinary sucralose, sucrose, lactulose, xylose and mannitol levels. A total of 41 patients with metastatic colorectal carcinoma or epithelial ovarian carcinoma were studied before and during chemotherapy with the combinations of cetuximab, irinotecan, 5-fluorouracil and leucovorin; bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin; or paclitaxel/ platinum. RESULTS: Compared to pretreatment values, a significant increase was observed during the first cycle of therapy in the percentage of sucrose, sucrose/mannitol ratio, lactulose and lactulose/ mannitol ratio in patients treated with the combination of bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin. No changes were observed in patients treated with cetuximab, irinotecan, 5-fluorouracil and leucovorin, but these patients had significantly higher baseline percentage of lactulose excretion and sucrose/mannitol and lactulose/ mannitol ratios. CONCLUSIONS: An increase in gastroduodenal and intestinal permeability was observed in patients treated with bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin, but not in patients treated with cetuximab, irinotecan, 5-fluorouracil and leucovorin. No significant increase in colonic permeability was observed, but the present method was insufficient to detect colonic permeability in a significant proportion of patients.
- MeSH
- dospělí MeSH
- duodenum metabolismus MeSH
- kolon metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- permeabilita MeSH
- protinádorové látky farmakokinetika MeSH
- sacharosa analogy a deriváty farmakokinetika MeSH
- senioři MeSH
- střevní sliznice metabolismus MeSH
- žaludeční sliznice metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVE: Gastrointestinal toxicity is one of the most common side effects of anticancer therapy. Measurement of intestinal permeability represents one of the potential methods of noninvasive laboratory assessment of gastrointestinal toxicity. The aim of the present study was to investigate intestinal permeability and vitamin A absorption in patients with chemotherapy-induced diarrhea (CID). METHODS: We have assessed intestinal permeability, by measuring absorption of lactulose, mannitol, xylose, and vitamin A absorption, in 11 patients with CID, 10 healthy controls, and 24 untreated patients with gastrointestinal tumors. Urinary lactulose, mannitol and xylose were measured by capillary gas chromatography and serum retinol and retinyl esters were determined by high performance liquid chromatography. The results obtained in patients and controls were compared by Mann-Whitney U test. RESULTS: Lactulose/mannitol and lactulose/xylose ratios were increased and retinol esters (retinyl palmitate and retinyl stearate) were decreased significantly in patients with CID. CONCLUSIONS: Measurements of intestinal permeability and vitamin A absorption may represent sensitive tools in the assessment of CID.
- MeSH
- dospělí MeSH
- gastrointestinální stromální tumory farmakoterapie komplikace patologie MeSH
- intestinální absorpce MeSH
- laktulosa moč MeSH
- lidé středního věku MeSH
- lidé MeSH
- mannitol moč MeSH
- mladý dospělý MeSH
- nádory rekta farmakoterapie komplikace patologie MeSH
- permeabilita MeSH
- prognóza MeSH
- protokoly protinádorové kombinované chemoterapie škodlivé účinky MeSH
- průjem farmakoterapie chemicky indukované metabolismus MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- studie případů a kontrol MeSH
- vitamin A metabolismus MeSH
- xylosa moč MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
- srovnávací studie MeSH
Measurement of intestinal permeability represents one of the potential methods of noninvasive laboratory assessment of gastrointestinal toxicity of anticancer therapy. We have assessed intestinal permeability (by measuring absorption of lactulose, mannitol, and xylose), vitamin A absorption and serum alpha-tocopherol in patients with non-small cell lung carcinoma or head and neck carcinomas treated with gefitinib. Lactulose, mannitol and xylose were determined by capillary gas chromatography, and retinol, alpha-tocopherol, retinyl stearate and retinyl palmitate were determined by high-performance liquid chromatography. Compared to healthy controls, patients had significantly increased lactulose/mannitol ratio and lower postprandial retinyl palmitate and retinyl stearate concentrations. Compared with pre-treatment values, xylose absorption was decreased and lactulose/mannitol and lactulose/xylose ratios were increased during the therapy. A significant decrease of serum alpha-tocopherol was evident throughout the course of therapy. In contrast, only minor alterations of vitamin A absorption were observed. In conclusion, an alteration in intestinal permeability reflected in increased lactulose/mannitol and lactulose/xylose ratios was observed during gefitinib therapy. Potential association between decreased serum alpha-tocopherol concentrations and the toxicity of gefitinib therapy should be further investigated.
- MeSH
- alfa-tokoferol krev MeSH
- chinazoliny farmakologie terapeutické užití MeSH
- dospělí MeSH
- intestinální absorpce účinky léků MeSH
- lidé středního věku MeSH
- lidé MeSH
- permeabilita účinky léků MeSH
- senioři MeSH
- střeva účinky léků MeSH
- studie případů a kontrol MeSH
- vitamin A metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Although gastrointestinal toxicity is one of the most common side effects of anticancer therapy, the diagnosis and assessment of this toxicity still depend mostly on anamnestic data. Measurement of intestinal permeability is one of potential methods of non-invasive laboratory evaluation of gastrointestinal toxicity. The aim of the present study was to investigate intestinal permeability, vitamin A absorption, serum alpha-tocopherol, and urinary neopterin in patients with rectal carcinoma treated with chemoradiation. We have studied intestinal permeability, vitamin A absorption, serum alpha-tocopherol, and urinary neopterin in 17 patients with rectal carcinoma treated with chemoradiation. Urinary lactulose, mannitol, and xylose were measured by capillary gas chromatography, and serum alpha-tocopherol, retinol, retinyl esters, and urinary neopterin were determined by high-performance liquid chromatography. Lactulose/mannitol ratio was increased 5 and 6 weeks after the start of the treatment. Serum alpha-tocopherol was decreased significantly throughout the course of treatment, but no significant changes were observed in postprandial serum concentrations of retinyl esters or in the concentrations of urinary neopterin. A correlation was observed between baseline parameters of intestinal permeability and urinary neopterin. The measurement of intestinal permeability using the lactulose/mannitol test may represent a sensitive tool in the detection of changes associated with chemoradiation in patients with rectal carcinoma. The therapy is also associated with a decrease of alpha-tocopherol.
- MeSH
- adenokarcinom farmakoterapie imunologie metabolismus radioterapie MeSH
- alfa-tokoferol krev MeSH
- antioxidancia metabolismus MeSH
- chromatografie plynová MeSH
- dietní sacharidy diagnostické užití farmakokinetika MeSH
- fluoruracil škodlivé účinky terapeutické užití MeSH
- intestinální absorpce účinky léků účinky záření MeSH
- kombinovaná terapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory rekta farmakoterapie imunologie metabolismus radioterapie MeSH
- neopterin moč MeSH
- protinádorové antimetabolity škodlivé účinky terapeutické užití MeSH
- sacharidy moč MeSH
- senioři MeSH
- vitamin A aplikace a dávkování analogy a deriváty krev farmakokinetika MeSH
- vysokoenergetická radioterapie škodlivé účinky MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Combination of platinum derivatives with paclitaxel is currently the standard front line regimen for patients with epithelial ovarian carcinoma, and represents also an active regimen in patients with metastatic breast or unknown primary carcinomas. Measurement of intestinal permeability represents one of the potential methods of noninvasive laboratory assessment of gastrointestinal mucositis induced by chemotherapy, but little is known about intestinal permeability in patients treated with paclitaxel or platinum. METHODS: Intestinal permeability was assessed in 36 breast and ovarian cancer patients treated with paclitaxel/platinum combination by measuring, using capillary gas chromatography, urinary sucrose, lactulose, xylose and mannitol after oral challenge. The significance of differences during the therapy compared to pre-treatment values was studied by Wilcoxon paired test. The differences between groups of patient were studied by Mann-Whitney U test. Fisher exact test was used to compare the frequency in different subgroups. RESULTS: After administration of the first dose, a significant (p < 0.05) decrease in xylose absorption and increased lactulose/mannitol, sucrose/mannitol, lactulose/xylose and sucrose/xylose ratios were observed, but these parameters returned subsequently to pre-treatment levels. Patients who experienced serious (grade 3 or 4) toxicity had at baseline significantly lower percentages of xylose, mannitol and sucrose, and higher lactulose/mannitol ratio. Nine of 13 (69%) patients with baseline lactulose/mannitol ratio 0.070 or above experienced serious toxicity compared to 4 out of 23 patients (17%) with the ratio below 0.070 (p = 0.002). Post-treatment lactulose, lactulose/mannitol, sucrose/mannitol and lactulose/xylose ratios were significantly increased in patients with serious toxicity. CONCLUSION: A transient significant increase in lactulose/monosaccharide and sucrose/monosaccharide ratios was observed in ovarian and breast cancer patients treated with paclitaxel and platinum. Increased lactulose absorption, lactulose/mannitol, sucrose/mannitol and lactulose/xylose ratios were evident in patients with grade 3 or 4 toxicity, and increased baseline lactulose/mannitol ratio predicted serious toxicity.
- MeSH
- adenokarcinom farmakoterapie metabolismus patologie MeSH
- cisplatina aplikace a dávkování MeSH
- dospělí MeSH
- financování organizované MeSH
- gastrointestinální trakt metabolismus MeSH
- intestinální absorpce účinky léků MeSH
- karboplatina aplikace a dávkování MeSH
- laktulosa metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- mannitol metabolismus MeSH
- monoklonální protilátky aplikace a dávkování MeSH
- nádory glandulární a epitelové farmakoterapie metabolismus patologie MeSH
- nádory prsu farmakoterapie metabolismus patologie MeSH
- nádory vaječníků farmakoterapie metabolismus patologie MeSH
- paclitaxel aplikace a dávkování MeSH
- permeabilita buněčné membrány účinky léků MeSH
- protokoly protinádorové kombinované chemoterapie terapeutické užití MeSH
- sacharasa metabolismus MeSH
- senioři MeSH
- xylosa metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
Pericellular oxygen concentration represents an important factor in the regulation of cell functions, including cell differentiation, growth and mitochondrial energy metabolism. Hypoxia in adipose tissue has been associated with altered adipokine secretion profile and suggested as a possible factor in the development of type 2 diabetes. In vitro experiments provide an indispensable tool in metabolic research, however, physical laws of gas diffusion make prolonged exposure of adherent cells to desired pericellular O2 concentrations questionable. The aim of this study was to investigate the direct effect of various O2 levels (1%, 4% and 20% O2) on the proteomic profile and triglyceride accumulation in 3T3-L1 differentiated preadipocytes using gas-permeable cultureware. Following differentiation of cells under desired pericellular O2 concentrations, cell lysates were subjected to two-dimensional gel electrophoresis and protein visualization using Coomassie blue staining. Spots showing differential expression under hypoxia were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. All identified proteins were subjected to pathway analysis. We observed that protein expression of 26 spots was reproducibly affected by 4% and 1% O2 (17 upregulated and 9 downregulated). Pathway analysis showed that mitochondrial energy metabolism and triglyceride synthesis were significantly upregulated by hypoxia. In conclusion, this study demonstrated the direct effects of pericellular O2 levels on adipocyte energy metabolism and triglyceride synthesis, probably mediated through the reversed tricarboxylic acid cycle flux.
- MeSH
- 2D gelová elektroforéza MeSH
- buněčná diferenciace účinky léků MeSH
- buňky 3T3-L1 MeSH
- citrátový cyklus účinky léků MeSH
- down regulace účinky léků MeSH
- kultivované buňky MeSH
- kyslík farmakologie MeSH
- lipidy biosyntéza MeSH
- lipogeneze účinky léků MeSH
- myši MeSH
- permeabilita MeSH
- plyny chemie MeSH
- počet buněk MeSH
- proteomika * MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- triglyceridy metabolismus MeSH
- tukové buňky cytologie účinky léků metabolismus MeSH
- upregulace účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
