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91.
Brem H Stojadinovic O Diegelmann RF Entero H Lee B Pastar I Golinko M Rosenberg H Tomic-Canic M 《Molecular medicine (Cambridge, Mass.)》2007,13(1-2):30-39
Chronic wounds, such as venous ulcers, are characterized by physiological impairments manifested by delays in healing, resulting in severe morbidity. Surgical debridement is routinely performed on chronic wounds because it stimulates healing. However, procedures are repeated many times on the same patient because, in contrast to tumor excision, there are no objective biological/molecular markers to guide the extent of debridement. To develop bioassays that can potentially guide surgical debridement, we assessed the pathogenesis of the patients' wound tissue before and after wound debridement. We obtained biopsies from three patients at two locations, the nonhealing edge (prior to debridement) and the adjacent, nonulcerated skin of the venous ulcers (post debridement), and evaluated their histology, biological response to wounding (migration) and gene expression profile. We found that biopsies from the nonhealing edges exhibit distinct pathogenic morphology (hyperproliferative/hyperkeratotic epidermis; dermal fibrosis; increased procollagen synthesis). Fibroblasts deriving from this location exhibit impaired migration in comparison to the cells from adjacent nonulcerated biopsies, which exhibit normalization of morphology and normal migration capacity. The nonhealing edges have a specific, identifiable, and reproducible gene expression profile. The adjacent nonulcerated biopsies have their own distinctive reproducible gene expression profile, signifying that particular wound areas can be identified by gene expression profiling. We conclude that chronic ulcers contain distinct subpopulations of cells with different capacity to heal and that gene expression profiling can be utilized to identify them. In the future, molecular markers will be developed to identify the nonimpaired tissue, thereby making surgical debridement more accurate and more efficacious. 相似文献
92.
Jaresová I Rozková D Spísek R Janda A Brázová J Sedivá A 《Microbes and infection / Institut Pasteur》2007,9(11):1359-1367
Toll-like receptors (TLR) are key components of innate immune system. As TLR activation could induce potentially harmful inflammatory response, activation of TLR signaling pathways has to be under tight control. Besides other control mechanisms, an inhibitory function of murine TLR4 splice variants was recently demonstrated. In this study we investigated expression of four TLR4 splice variants in human antigen presenting cells (APC). Furthermore, we studied modification in TLR4 splice variants expression in APC in cystic fibrosis (CF) patients chronically infected by Gram-negative bacteria. We developed a novel reliable real-time PCR detection system that allowed monitoring of individual TLR4 splice variants expression. In APC from healthy donors we detected a characteristic transient increase of two out of four splice variants after lipopolysaccharide (LPS) stimulation. Similarly to murine TLR4, one of these variants, NM 003266, might translate to a potentially inhibitory protein. In contrast to controls, CF monocytes had significantly changed LPS-induced expression of TLR4 gene and its variants including reduced ability to up-regulate the expression of the potentially inhibitory variant upon stimulation. In accordance with this observation, monocytes from CF patients produced significantly more tumor necrosis factor after LPS stimulation than healthy controls. Our results thus describe the kinetics of TLR4 splicing variants expression after LPS stimulation and indicate a possible alteration of its regulation in CF patients. 相似文献
93.
94.
The application of a specific species of willow—Salix amygdalina L., marked by high transpiration ability—is a cheap and effective method of landfill leachate disposal. A 2-year study examined the effectiveness of leachate evapotranspiration from soil–plant systems with willow species S. amygdalina L. Evapotranspiration from soil–plant systems planted with willow was from 1.28 up to 5.12 times higher than evaporation from soil surface barren of vegetation. This proves the usefulness of soil–plant systems with willow in landfill leachate treatment through vaporization. Evapotranspiration efficiency, as opposed to total amount of water added into the lysimeter, was not strong enough to vaporize all input of the landfill leachate in the lysimeters. This may indicate that the ground water requires isolation when soil systems remain under landfill leachate irrigation. Linear dependence between willow biomass growth and transpiration was observed to be significant (p < 0.05). Additionally, the research showed that the application of sewage sludge into the soil caused an increase in vaporization efficiency. 相似文献
95.
Wioleta?Kellmann-Sopy?aEmail author Les?aw?B.?Lahuta Irena?Gie?wanowska Ryszard?J.?Górecki 《Acta Physiologiae Plantarum》2015,37(6):118
The accumulation of soluble carbohydrates in maturing diaspores of flowering plants comprising Arctic populations of Cerastium alpinum, indigenous Antarctic species Colobanthus quitensis and Deschampsia antarctica, and cosmopolitan Poa annua from the Antarctic was investigated. For comparative purposes, the diaspores of two species of flowering plants growing in the area of Olsztyn (Poland), Poa annua (Poaceae) and Cerastium arvense (Caryophyllaceae) were used. A qualitative and quantitative analysis of soluble carbohydrates conducted by means of high-resolution gas chromatography showed that monosaccharides (glucose and fructose), maltose and sucrose, raffinose, myo-inositol and galactinol are ubiquitous in developing and mature diaspores among investigated species. Moreover, D. antarctica and P. annua caryopses additionally contained stachyose and 1-kestose; the seeds of Caryophyllaceae studied were found to contain d-pinitol and d-ononitol. The development and maturation of the seeds of polar Caryophyllaceae and Poaceae were accompanied by the changes in the concentration of their soluble carbohydrates. During maturation, seeds accumulated galactinol and raffinose family of oligosaccharides (RFOs), except C. quitensis. Although seeds of the studied Caryophyllaceae contained d-pinitol and lower amounts of d-ononitol, they did not accumulate α-d-galactoside derivatives of mentioned cyclitols. P. annua caryopses, occurring in the Antarctic, were found to accumulate considerably higher amounts of sucrose and 1-kestose than those developed in Olsztyn. 相似文献
96.
97.
Erebia aethiops is an aberrant lowland representative of a predominately arctic and alpine butterfly genus. We used behavioral records obtained
during a mark-recapture study (MR) to extract information about its adult diurnal and within-season activity, and to compare its activity with previously studied mountain Erebia species. Similarly to them, maintenance activities (nectaring, basking) increased with season. Contrary to mountain relatives,
E. aethiops nectars in morning hours and spends the hottest parts of the day in the shade. Therefore, high rather than low temperatures
seem to be limiting E. aethiops activity. We also compared microhabitat preferences of sexes, finding that females preferred grassy patches, whereas males
often entered scrub and sparse canopy forest. The study illustrates the utility of auxiliary MR data to analyze butterfly
activity, and points to the necessity of finely structured habitat mosaics for E. aethiops, an open woodland species that retracted to abandoned grasslands and has become vulnerable in Central Europe. 相似文献
98.
The aim of this study was to investigate the influence of experimental conditions on levothyroxine sodium release from two
immediate-release tablet formulations which narrowly passed the standard requirements for bioequivalence studies. The in vivo study was conducted as randomised, single-dose, two-way cross-over pharmacokinetic study in 24 healthy subjects. The in vitro study was performed using various dissolution media, and obtained dissolution profiles were compared using the similarity
factor value. Drug solubility in different media was also determined. The in vivo results showed narrowly passing bioequivalence. Considering that levothyroxine sodium is classified as Class III drug according
to the Biopharmaceutics Classification System, drug bioavailability will be less sensitive to the variation in its dissolution
characteristics and it can be assumed that the differences observed in vitro in some of investigated media probably do not have significant influence on the absorption process, as long as rapid and
complete dissolution exists. The study results indicate that the current regulatory criteria for the value of similarity factor
in comparative dissolution testing, as well as request for very rapid dissolution (more than 85% of drug dissolved in 15 min),
are very restricted for immediate-release dosage forms containing highly soluble drug substance and need further investigation.
The obtained results also add to the existing debate on the appropriateness of the current bioequivalence standards for levothyroxine
sodium products. 相似文献
99.
Wnt-signalling is involved in a number of biological processes in the course of embryonic development, cell fate determination, proliferation, stem cell maintenance and oncogenesis. Wnt ligands are secreted glycoproteins and the number of Wnt isoforms varies between five in nematodes and 27 in fish. The highly conserved group of Wnt7 genes has been found to signal via at least three Wnt-signalling pathways dependent on the developmental context. These ligands have been identified as important regulators in a number of processes ranging from formation of bones, lungs, kidneys, reproductive organs and placenta to vasculogenesis and synaptogenesis in the brain. The importance of Wnt7 function is underscored by their implication in disease syndromes in man. Unlike the single Wnt7a and Wnt7b mammalian genes we find that the zebrafish genome contains two paralogues genes for each Wnt7 ligand. Here, we compare these four Wnt7 genes evolutionarily and analyse their expression during the first two days of embryonic development. We find Wnt7 genes mainly expressed in a number of CNS structures at developmental stages at which patterning and neural specification takes place. The timely and spatially overlapping as well as complementary gene expression suggests diverse as well as redundant involvements during brain development. 相似文献
100.
Baranowska I Magiera S Baranowski J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(9-10):615-626
A rapid-resolution ultra high-performance liquid chromatography separation method (UHPLC) for the simultaneous determination of the following β-blockers: milrinone, sotalol, metoprolol, propranolol and carvedilol, and their metabolites: 5′-hydroxylphenyl-carvedilol, O-desmethylcarvedilol, 4-hydroxypropranolol, α-hydroxy-metoprolol, O-desmethyl-metoprolol; the following isoflavones: genistein, daidzein, glycitin, glycitein, puerarin and biochanin A; as well as their metabolites: dihydrogenistein, desmethylglycitein, 8-hydroxygenistein, daidzein-7,4′-diglucoside, 8-hydroxydaidzein, dihydrobiochanin A in human urine was optimized. The analysed compounds were extracted from human urine by means of solid phase extraction (SPE). The effective UHPLC separation of the examined compounds was applied on a Hypersil GOLD? (50 mm × 2.1 mm, 1.9 μm) column with a gradient mobile phase system and a UV detector. The complete separation of all analytes was achieved within 8.0 min. The method was validated for the determination of the aforementioned substances in human urine. The linear ranges, limits of detection (LOD) and limits of quantification (LOQ) for β-blockers, isoflavones and their metabolites were determined. The intra- and inter-day precision (%C.V.) was less than 4.48%, and the intra-day and inter-day accuracy was less than 4.74%. The tested SPE sorbent proved that appropriate absolute recoveries can be obtained for Oasis HLB (Waters). The mean recovery of the analytes, using the new SPE procedure, amounted from 70.14% to 99.85%. The present paper reports, for the first time, the method for the determination of β-blockers, isoflavones and their metabolites in human urine samples. The newly developed method was suitably validated and successfully applied for the analysis of the certain of the aforementioned analytes in human urine samples obtained from the patients suffering cardiovascular disease. 相似文献