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41.
Whereas in severe burns cultured human epithelial cells may well serve as a life saving method, the true value of tissue-engineered skin products in chronic wound care has yet to be clearly defined. Among other well-known clinical problems, the engraftment rate of commercially available multilayered "sheet grafts" has been shown to vary extremely. Adherence of transplanted cells to the wound bed--especially in the presence of potential wound contamination-- is one of the crucial aspects of this technique. Keratinocyte suspensions in a natural fibrin sealant matrix can potentially treat a variety of skin defects. In acute burn wounds, as well as in chronic wounds the clinical application of this type of tissue-engineered skin substitute demonstrates the capacity of cultured human autologous keratinocytes in a fibrin sealant matrix to adhere to wound beds, attach and spread over the wound resulting in reepithelialization of both acute and chronic wounds. In full thickness burns the combination of this new tool with allogenic dermis is a promising option to achieve complete dermal-epidermal reconstitution by means of tissue engineering and guided tissue repair. When transferring this technique into the treatment of chronic wounds we found an optimal preparation of such recipient wound beds to be crucial to the success. The additional application of continuous negative pressure (vacuum therapy) and preliminary chip skin grafting to optimally prepare the recipient site may be helpful tools to achieve such well-prepared and graftable surfaces. Prospective controlled comparative studies should be designed to further assess the clinical efficacy of this technique. 相似文献
42.
BACKGROUND: IL-18 is a pleiotropic cytokine involved in the polarisation of T-cell response. This study was performed to determine whether or not IL-18 is detectable in phytohemagglutinin (PHA) or betalactoglobulin (BLG) stimulated supernatants of cord blood mononuclear cells (CBMC) and to study the in vitro effect of IL-18 on the interferon (IFN)-gaamma and IL-13 release of CBMC of healthy neonates. METHODS: CBMC of neonates were isolated by Ficoll density centrifugation. The cytokines IFN-gamma, IL-13 and IL-18 in the cell culture supernatants were measured using the ELISA technique following stimulation with a unspecific (PHA 20 microg/ml) and an allergen-specific stimulus (BLG 25 microg/ml). In order to study the in vitro effect of IL-18, CBMC were stimulated either with medium alone or with IL-18, IL-18 + PHA and IL-18 + BLG. RESULTS: IL-18 levels in supernatants of CBMC were low and did not vary significantly between unstimulated and PHA or BLG stimulated cell cultures (median 21.4; 23.5 and 15.5 pg/ml, respectively). IFN-gamma and IL-13 levels were significantly higher in response to PHA and BLG (PHA: IFN-gamma, 6154; IL-13, 4357; BLG: IFN-gamma, 801; IL-13, 249 pg/ml) compared to unstimulated cell cultures. The addition of IL-18 to PHA or BLG stimulated CBMC significantly enhanced the IFN-gamma release (PHA: 6154; PHA + IL-18: 13474, p = 0.0001; BLG: 801; BLG + IL-18: 1077, p = 0.008). In comparison to incubation without IL-18, the release of IL-13 was invariable or even reduced, when CBMC were stimulated with PHA + IL-18 (4026, p = 0.16) or BLG + IL-18 (124, p = 0.0001) compared to stimulation of CBMC with PHA (4357 pg/ml) or BLG (249 pg/ml) alone. CONCLUSIONS: IL-18 is detectable in supernatants of CBMC. We observed a significant effect of IL-18 + PHA as well as IL-18 + BLG on IFN-gamma release in vitro. Based on our findings we conclude that IL-18 could act as a strong TH1-inducing factor on stimulated CBMC also in vivo. 相似文献
43.
Kopp UC Cicha MZ Smith LA 《American journal of physiology. Regulatory, integrative and comparative physiology》2002,282(6):R1618-R1627
Increasing renal pelvic pressure increases afferent renal nerve activity (ARNA) by a PGE(2)-mediated release of substance P (SP) from renal pelvic nerves. The role of cAMP activation in the PGE(2)-mediated release of SP was studied by examining the effects of the adenylyl cyclase (AC) activator forskolin and AC inhibitor dideoxyadenosine (DDA). Forskolin enhanced the bradykinin-mediated release of SP from an isolated rat renal pelvic wall preparation, from 7.3 +/- 1.3 to 15.6 +/- 3.0 pg/min. PGE(2) at a subthreshold concentration for SP release mimicked the effects of forskolin. The EP(2) receptor agonist butaprost, 15 microM, and PGE(2), 0.14 microM, produced similar increases in SP release, from 5.8 +/- 0.8 to 17.0 +/- 2.3 pg/min and from 8.0 +/- 1.3 to 21.6 +/- 2.7 pg/min. DDA blocked the SP release produced by butaprost and PGE(2). The PGE(2)-induced release of SP was also blocked by the PKA inhibitors PKI(14-22) and H-89. Studies in anesthetized rats showed that renal pelvic administration of butaprost, 10 microM, and PGE(2), 0.14 microM, resulted in similar ARNA responses, 1,520 +/- 390 and 1,170 +/- 270%. s (area under the curve of ARNA vs. time) that were blocked by DDA. Likewise, the ARNA response to increased renal pelvic pressure, 7,180 +/- 710%. s, was blocked by DDA. In conclusion, PGE(2) activates the cAMP-PKA pathway leading to a release of SP and activation of renal pelvic mechanosensory nerve fibers. 相似文献
44.
Marchart E Kopp B 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,792(2):363-368
A simple method for the rapid separation and quantification of flavone-O- and C-glycosides in A. setacea W. et K. by capillary zone electrophoresis (CZE) with UV detection is described. Using 25 mM sodium borate with 20% (v/v) of methanol (pH 9.3) as running buffer sufficient separation of the analytes was achieved within 19 min. For the quantitative determination isorhamnetin-3-O-rutinoside was used as internal standard. The method was successfully applied to a rapid characterisation of the flavonoid complex and a precise quantification of the single and total amount of the flavonoids in different samples of A. setacea. 相似文献
45.
Hellström A Aronsson M Axelson C Kyllerman M Kopp S Steffenburg S Strömland K Westphal O Wiklund L Albertsson Wikland K 《Hormone research》2000,53(Z1):19-25
The data in this article are based on investigations performed in 25 children with suspected septo-optic dysplasia (SOD). There are many signs and methods that help in the diagnosis of SOD. In particular, the ocular fundus, abnormalities of the hypothalamo-pituitary axis and other midline brain structures should be described. In order to achieve a more holistic and functional diagnosis, the degree of neurological, neuropsychiatric and psychological involvement should also be stated. It has been suggested that SOD is associated with autosomal recessive inheritance, and it can be speculated that it is the result of genetic and environmental influences early in gestation. An early diagnosis can favourably influence the outcome of the affected child. 相似文献
46.
The Arabidopsis COP1 protein functions as a developmental regulator, in part by repressing photomorphogenesis in darkness. Using complementation of a cop1 loss-of-function allele with transgenes expressing fusions of cop1 mutant proteins and beta-glucuronidase, it was confirmed that COP1 consists of two modules, an amino terminal module conferring a basal function during development and a carboxyl terminal module conferring repression of photomorphogenesis. The amino-terminal zinc-binding domain of COP1 was indispensable for COP1 function. In contrast, the debilitating effects of site-directed mutations in the single nuclear localization signal of COP1 were partially compensated by high-level transgene expression. The carboxyl-terminal module of COP1, though unable to substantially ameliorate a cop1 loss-of-function allele on its own, was sufficient for conferring a light-quality-dependent hyperetiolation phenotype in the presence of wild-type COP1. Moreover, partial COP1 activity could be reconstituted in vivo from two non-covalently linked, complementary polypeptides that represent the two functional modules of COP1. Evidence is presented for efficient association of the two sub-fragments of the split COP1 protein in Arabidopsis and in a yeast two-hybrid assay. 相似文献
47.
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49.
Helena Kopp Kallner Louise Thunell Jan Brynhildsen Mia Lindeberg Kristina Gemzell Danielsson 《PloS one》2015,10(5)
ObjectiveTo describe contraceptive use and attitudes towards contraceptive use in Sweden which has the highest abortion rate in Western Europe. Secondary objectives were to investigate knowledge of contraceptive methods and outcomes of unplanned and unwanted pregnancies.DesignTelephone survey.SettingNational survey of women living in Sweden.PopulationWomen between 16 and 49 years.MethodsThe survey contained 22 questions with free text and multi choice answers on demographics, contraceptive use, knowledge of and attitudes towards contraception, the importance of monthly bleeding and experience of unintended pregnancy.ResultsA total of 1001 women participated in the survey. Of all women, 721/1001 (72.1%) currently used contraception whereas 268/1001 (26.8%) women did not. Long acting reversible contraception, (LARC; implant and intra uterine contraception) was used by 24.3% of women. The unmet need of contraception in Sweden was estimated at 8.9% (89/1001 women). A total of 781 (78%) women had never experienced an unintended pregnancy whereas 220 (22%) women had had at least one unintended pregnancy. Users and non-users alike stated that one of the most important characteristics of a contraceptive method is its effectiveness.ConclusionsSweden has a large unmet need for contraception. Furthermore, a large proportion of women have experienced at least one unintended pregnancy. Increasing contraceptive use and promotion of LARC is a possible way forward in the effort to reduce the rates of unwanted pregnancies. 相似文献
50.
Matthias Hammon Susan Grossmann Peter Linz Christoph Kopp Anke Dahlmann Christoph Garlichs Rolf Janka Alexander Cavallaro Friedrich C. Luft Michael Uder Jens Titze 《PloS one》2015,10(10)