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991.
Kolakovic R Laaksonen T Peltonen L Laukkanen A Hirvonen J 《International journal of pharmaceutics》2012,430(1-2):47-55
Nanofibrillar cellulose (also referred to as cellulose nanofibers, nanocellulose, microfibrillated or nanofibrillated cellulose) has gained a lot of attention in recent years in different research areas including biomedical applications. In this study we have evaluated the applicability of nanofibrillar cellulose (NFC) as a material for the formation of matrix systems for sustained drug delivery. For that purpose, drug loaded NFC microparticles were produced by a spray drying method. The microparticles were characterized in terms of size and morphology, total drug loading, and physical state of the encapsulated drug. Drug release from the microparticles was assessed by dissolution tests, and suitable mathematical models were used to explain the drug releasing kinetics. The particles had spherical shapes with diameters of around 5 μm; the encapsulated drug was mainly in amorphous form. The controlled drug release was achieved. The drug releasing curves were fitted to a mathematical model describing the drug releasing kinetics from a spherical matrix. Different drugs had different release kinetics, which was a consequence of several factors, including different solubilities of the drugs in the chosen medium and different affinities of the drugs to the NFC. It can be concluded that NFC microparticles can sustain drug release by forming a tight fiber network and thus limit drug diffusion from the system. 相似文献
992.
Tahvanainen M Rotko T Mäkilä E Santos HA Neves D Laaksonen T Kallonen A Hämäläinen K Peura M Serimaa R Salonen J Hirvonen J Peltonen L 《International journal of pharmaceutics》2012,422(1-2):125-131
In this study, indomethacin-loaded thermally oxidized mesoporous silicon microparticles (TOPSi-IMC) were formulated into tablets with excipients in order to improve the dissolution and permeability properties of the poorly soluble drug. Formulations of TOPSi-IMC particles and excipients were prepared at different TOPSi-IMC particle ratios (25, 30 and 35%). The formulations were compressed by direct compression technique with a single punch tablet machine. For comparison, a formulation containing the bulk IMC (indomethacin) and the same excipients without thermally oxidized mesoporous silicon microparticles particles (TOPSi) was prepared and compressed into tablets. The TOPSi-IMC tablets were characterised according to weight, thickness, crushing strength, disintegration time and dissolution rate. The results of this study show that TOPSi-IMC particles can be compressed to a conventional tablet. The release rate of the drug and its permeation across intestinal cells model (Caco-2) from TOPSi-IMC tablets was improved compared to the bulk IMC tablets. The dissolution rate and permeability of IMC from the tablets decreased with increasing ratio of the TOPSi-IMC particles in the formulation. The phenomenon is, presumably, a result of the loss of unique pore structure of the particles due to deformation of the particles under the compression load. 相似文献
993.
He Y Esser P Heinemann A Bruckner-Tuderman L Has C 《The American journal of pathology》2011,178(3):975-982
Kindlins are a novel family of intracellular adaptor proteins in integrin-containing focal adhesions. Kindlin-1 and -2 are expressed in the skin, but whether and how they cooperate in adult epithelial cells have remained elusive. We uncovered the overlapping roles of kindlin-1 and -2 in maintaining epithelial integrity and show that the phenotype of kindlin-1-deficient cells can be modulated by regulating kindlin-2 gene expression and vice versa. The experimental evidence is provided by use of human keratinocyte cell lines that express both kindlins, just kindlin-1 or kindlin-2, or none of them. Double deficiency of kindlin-1 and -2 had significant negative effects on focal adhesion formation and actin cytoskeleton organization, cell adhesion, survival, directional migration, and activation of β(1) integrin, whereas deficiency of one kindlin only showed variable perturbation of these functions. Cell motility and formation of cell-cell contacts were particularly affected by lack of kindlin-2. These results predict that kindlin-1 and -2 can functionally compensate for each other, at least in part. The high physiologic and pathologic significance of the compensation was emphasized by the discovery of environmental regulation of kindlin-2 expression. UV-B irradiation induced loss of kindlin-2 in keratinocytes. This first example of environmental regulation of kindlin expression has implications for phenotype modulation in Kindler syndrome, a skin disorder caused by kindlin-1 deficiency. 相似文献
994.
Kopecki Z Arkell RM Strudwick XL Hirose M Ludwig RJ Kern JS Bruckner-Tuderman L Zillikens D Murrell DF Cowin AJ 《The Journal of pathology》2011,225(3):401-413
Epidermolysis bullosa (EB) is a severe genetic skin fragility syndrome characterized by blister formation. The molecular basis of EB is still largely unknown and wound healing in patients suffering from EB remains a major challenge to their survival. Our previous studies have identified the actin remodelling protein Flightless I (Flii) as an important mediator of wound repair. Here we identify Flii as a novel target involved in skin blistering. Flii expression was significantly elevated in 30 patients with EB, most prominently in patients with recessive dystrophic EB (RDEB) who have defects in production of type VII collagen (ColVII). Using an autoimmune ColVII murine model of EB acquisita (EBA) and an immunocompetent-ColVII-hypomorphic genetic mouse model of RDEB together with murine Flii alleles, we investigated the contribution of Flii to EB. Overexpression of Flii produced severe blistering post-induction of EBA, while decreased Flii reduced blister severity, elevated integrin expression, and improved ColVII production. Flii(+/-) blistered skin showed reduced α-SMA, TGF-β1, and Smad 2/3 expression, suggesting that decreasing Flii may affect fibrosis. In support of this, Flii-deficient fibroblasts from EBA mice were less able to contract collagen gels in vitro; however, addition of TGF-β1 restored collagen contraction, suggesting an interplay between Flii and TGF-β1. Elevated Flii gene and protein expression was further observed in the blisters of ColVII hypomorphic mice, a murine model of RDEB, suggesting that reducing Flii in blistered skin could be a potential new approach for treating patients with EB. 相似文献
995.
Anna-Maija TolppanenSeppo Helisalmi Mikko HiltunenMarjukka Kolehmainen Ursula Schwab Tuula Pirttilä Leena PulkkinenMatti Uusitupa Hilkka Soininen 《Neurobiology of aging》2011,32(3):546
The tenomodulin gene (TNMD, locus Xq-22) encodes an angiogenesis inhibitor. It is an interesting candidate gene for Alzheimer's disease (AD), since it is expressed in brain, alterations in angiogenesis have been linked to AD and in our previous studies we have observed associations between TNMD and phenotypes, which are related to increased risk of AD. The common sequence variation in the TNMD was not associated with prevalence of AD among 526 cases and 672 controls. However, a significant interaction (p = 0.002) between rs5966709 and the APOE ε4-allele status was observed in women. Among the ε4-allele carriers, the women with rs5966709-TT genotype had smaller risk for having AD than those with other genotypes (odds ratio 0.47, p = 0.019, false discovery rate 10.4%). According to these results the sequence variation of TNMD is not associated with AD, but might modify the effect of APOE ε4-allele in women. 相似文献
996.
Prajwal P. Nandekar Khaled M. Tumbi Nitu Bansal Vijay P. Rathod Leena B. Labhsetwar Neelagiri Soumya Sushma Singh Abhay T. Sangamwar 《Medicinal chemistry research》2013,22(8):3728-3742
The benzothiazole scaffold has been reported to have antitumor activity in tumor-sensitive cell lines by proposed mechanism of CYP1A1 induction. CYP1A1 has been shown to participate in metabolism of benzothiazole scaffold to its reactive metabolites. CYP1A1 has also been proposed as drug target for anti-cancer chemotherapy for its differential and selective overexpression in tumor cells. Herein, we have reported NSC745689 from the series of new pyrimidobenzothiazoles (NSC745689) for its promising antitumor activity against non-small cell lung cancer cell line in National Cancer Institute (NCI) 60 human cancer cell line screen. We confirmed CYP1A1 specificity for NSC745689 by ethoxyresorufin-O-dethylase (EROD) assay. Furthermore, we investigated the metabolism of NSC745689 using MetaSite software and quantum mechanical study. The necessary structural changes in NSC745689 scaffold to potentiate its CYP1A1 binding and antitumor activity were suggested using molecular docking and molecular dynamics analysis. 相似文献
997.
Ylikontiola L Sundqvuist K Sàndor GK Törmälä P Ashammakhi N 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2004,97(3):312-317
OBJECTIVE: Bioresorbable osteofixation devices are being increasingly used in orthognathic surgery and in cases of trauma to avoid problems associated with conventional metal osteofixation devices. The aim of this clinical study was to assess the reliability and efficacy of bioresorbable self-reinforced poly-L/DL-lactide (SR-P(L/DL)LA 70/30) plates and screws in the fixation of mandibular fractures in adults. STUDY DESIGN: Ten patients (20 to 49 years old) with isolated anterior mandibular parasymphyseal fractures were treated by means of open reduction and internal fixation using SR-P(L/DL)LA 70/30 bioresorbable plates and screws. RESULTS: During the minimum of 6 months of follow-up, no problems were encountered except for 1 case where a plate became exposed intraorally and infected. This required debridement and later excision of the exposed part of the plate. Despite this setback the fractured bone healed well. CONCLUSIONS: SR-P(L/DL)LA 70/30 plates and screws are reliable for internal fixation of anterior mandibular fractures in adults. Proper soft tissue coverage should be ensured to avoid plate exposure. Should implant exposure occur, it might be necessary to excise the exposed part after fracture healing (6-8 weeks postoperatively). 相似文献
998.
999.
D Turner A Levine JC Escher AM Griffiths RK Russell A Dignass JA Dias J Bronsky CP Braegger S Cucchiara L de Ridder UL Fagerberg S Hussey JP Hugot S Kolacek KL Kolho P Lionetti A Pærregaard A Potapov R Rintala DE Serban A Staiano B Sweeny G Veerman G Veres DC Wilson FM Ruemmele 《Journal of pediatric gastroenterology and nutrition》2012,55(3):340-361
BACKGROUND AND AIMS:: Pediatric ulcerative colitis (UC) shares many features with adult-onset disease but there are some unique considerations; therefore, therapeutic approaches have to be adapted to these particular needs. We aimed to formulate guidelines for managing UC in children based on a systematic review (SR) of the literature and a robust consensus process. The present article is a product of a joint effort of the European Crohn's and Colitis Organization (ECCO) and the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN). METHODS:: A group of 27 experts in pediatric IBD participated in an iterative consensus process including 2 face-to-face meetings, following an open call to ESPGHAN and ECCO members. A list of 23 predefined questions were addressed by working subgroups based on a SR of the literature. RESULTS:: A total of 40 formal recommendations and 68 practice points were endorsed with a consensus rate of at least 89% regarding initial evaluation, how to monitor disease activity, the role of endoscopic evaluation, medical and surgical therapy, timing and choice of each medication, the role of combined therapy, and when to stop medications. A management flowchart, based on the Pediatric Ulcerative Colitis Activity Index (PUCAI), is presented. CONCLUSIONS:: These guidelines provide clinically useful points to guide the management of UC in children. Taken together, the recommendations offer a standardized protocol that allows effective, timely management and monitoring of the disease course, while acknowledging that each patient is unique. 相似文献
1000.
Despite extensive experience over the past 25 y in managing growth failure with growth hormone (rhGH), predicting treatment
efficacy in individual children remains a challenge. In this paper, the authors present the methods that are currently available
to clinicians for predicting the growth response, and other more sophisticated techniques which have the potential to pave
the way for individualised therapy in the future. 相似文献