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991.
Helga Bergmeister Catharina Schreiber Christian Grasl Ingrid Walter Roberto Plasenzotti Martin Stoiber David Bernhard Heinrich Schima 《Acta biomaterialia》2013,9(4):6032-6040
Pore size and porosity control the rate and depth of cellular migration in electrospun vascular fabrics and thus have a strong impact on long-term graft success. In this study we investigated the effect of graft porosity on cell migration in vitro and in vivo. Polyurethane (PU) grafts were fabricated by electrospinning as fine-mesh, low-porosity grafts (void fraction (VF) 53%) and coarse-mesh, high-porosity grafts (VF 80%). The fabricated grafts were evaluated in vitro for endothelial cell attachment and proliferation. Prostheses were investigated in a rat model for either 7 days, 1, 3 or 6 months (n = 7 per time point) and analyzed after retrieval by biomechanical analysis and various histological techniques. Cell migration was calculated by computer-assisted morphometry. In vitro, fine-pore mesh favored early cell attachment. In vivo, coarse mesh grafts revealed significantly higher cell populations at all time points in all areas of the conduit wall. Biomechanical tests indicated sufficient compliance, tensile and suture retention strength before and after implantation. Increased porosity improves host cell ingrowth and survival in electrospun conduits. These conduits show successful natural host vessel reconstitution without limitation of biomechanical properties. 相似文献
992.
Annelies Laeremans Julie Nys Walter Luyten Rudi D’Hooge Melissa Paulussen Lut Arckens 《Brain structure & function》2013,218(1):123-130
AMIGO2, or amphoterin-induced gene and ORF (open reading frame) 2, belongs to the leucine-rich repeats and immunoglobulin superfamilies. The protein is a downstream target of calcium-dependent survival signals and, therefore, promotes neuronal survival. Here, we describe the mRNA distribution pattern of AMIGO2 throughout the mouse brain with special emphasis on the hippocampus. In the Ammon’s horn, a detailed comparison between the subregional mRNA expression patterns of AMIGO2 and Pcp4 (Purkinje cell protein 4)—a known molecular marker of hippocampal CA2 (Cornu Ammonis 2)—revealed a prominent AMIGO2 mRNA expression level in both the CA2 and the CA3a (Cornu Ammonis 3a) subregion of the dorsal and ventral hippocampus. Since this CA2/CA3a region is particularly resistant to neuronal injury and neurotoxicity [Stanfield and Cowan (Brain Res 309(2):299–307 1984); Sloviter (J Comp Neurol 280(2):183–196 1989); Leranth and Ribak (Exp Brain Res 85(1):129–136 1991); Young and Dragunow (Exp Neurol 133(2):125–137 1995); Ochiishi et al. (Neurosci 93(3):955–967 1999)], we suggest that the expression pattern of AMIGO2 indeed fits with its involvement in neuroprotection. 相似文献
993.
Mohammad Hajighasemi‐Ossareh Rachel M. Borthwell Jeremy E. Stevens Walter E. Finkbeiner Jonathan H. Widdicombe 《Anatomical record (Hoboken, N.J. : 2007)》2013,296(11):1768-1774
A transgenic ferret model of cystic fibrosis has recently been generated. It is probable that malfunction of airway mucous glands contributes significantly to the airway pathology of this disease. The usefulness of the ferret model may therefore depend in part on how closely the airway glands of ferrets resemble those of humans. Here, we show that in the ferret trachea glands are commonest in its most ventral aspect and disappear about half way up the lateral walls; they are virtually absent from the dorsal membranous portion. Further, the aggregate volume of glands per unit mucosal surface declines progressively by about 60% between the larynx and the carina. The average frequency of glands openings for the ferret trachea as a whole is only about one‐fifth that in humans (where gland openings are found at approximately the same frequency throughout the trachea). Glands in the ferret trachea are on average about one‐third the size of those in the human. Therefore, the aggregate volume of tracheal glands (per unit mucosal surface area) in the ferret is only about 6% that in humans. As in other mammalian species, airway glands in the ferret disappear at an airway internal diameter of ~1 mm, corresponding approximately in this species to airway generation 6. Anat Rec, 296:1768–1774, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
994.
Kerry L. Cheesman Robert T. Chatterton Jr. Craig W. Beattie Carl B. Wallemark Walter W. Hauck 《Journal of immunoassay & immunochemistry》2013,34(1-2):59-70
Rat pituitary hormone radioimmunoassays (RIAs) are widely used in reproductive research, yet data on specificity and binding characteristics of many of the antisera are not widely available. This report characterizes one set of rat antisera supplied by the National Institutes of Health (USA). Rat follicle-stimulating hormone (FSH) and thyrotropin-stimulating hormone (TSH) antisera appear specific, but TSH exhibited significant competition in the rat luteinizing hormone (LH) assay. In addition, statistically significant nonparallelism was demonstrable in all three assay systems. This creates further problems in characterizing antisera cross-reactivity and may make potency estimates for pituitary standards inaccurate. 相似文献
995.
996.
Monique Gomes Salles Tiburcio Laís Anversa Kelly Aparecida Kanunfre Antonio Walter Ferreira Virmondes Rodrigues Júnior Luciana de Almeida Silva 《Clinical and Vaccine Immunology : CVI》2013,20(11):1697-1702
IgG avidity tests are used to discriminate acute from chronic infections. There are few reports on the IgG avidity profile of patients with visceral leishmaniasis (VL). This study investigated the anti-Leishmania IgG avidity in patients with classic VL (n = 10), patients showing clinical cure after treatment (n = 18), and asymptomatic subjects with at least one positive Leishmania test (n = 20). All subjects were from areas in Brazil where VL is endemic. Serum samples were collected from each subject on two different occasions. IgG avidity was evaluated by Western blotting. The proportion of high-avidity antibodies was higher in all samples from patients with classic VL. In contrast, low-avidity antibodies predominated in subjects with a history of VL, including 13 cases (72.2%) in the first assessment and 14 (77.8%) in the second. Fifteen (75%) of the asymptomatic subjects presented a predominance of low-avidity antibodies in the first assessment, and the frequency of high-avidity antibodies increased over time in seven subjects (35%) of this group. Antibodies against the 14- and/or 16-kDa antigen fraction were detected in the first assessment in all patients with classic VL, in 10 (55.5%) treated patients, and in 10 (50%) asymptomatic subjects. These were high-avidity antibodies in most cases. In the asymptomatic group, an increase in IgG avidity against the 14- and/or 16-kDa antigen fraction was observed in three cases (15%). The results indicate distinct responses in infected and asymptomatic subjects, probably associated with the length of time after infection. In this respect, IgG avidity tests represent a new approach to better characterize asymptomatic VL. 相似文献
997.
I. Sabolić Pipinić V. M. Varnai R. Turk D. Breljak S. Kezić J. Macan 《International journal of immunogenetics》2013,40(3):192-198
Filaggrin gene (FLG) null mutations are considered associated with atopic dermatitis. This study was conducted to determine the prevalence of FLG null mutations R501X, 2282del4, R2447X and S3247X in the Croatian population and their role in the occurrence of allergic diseases including atopic dermatitis, allergic rhinitis, asthma and allergic contact dermatitis (ACD). Study enrolled 440 freshmen with defined allergic diseases by means of both present symptoms in International Study of Asthma and Allergies in Childhood questionnaire (relevant respiratory and/or skin symptoms) and markers of allergic sensitization (positive skin prick and/or patch test). FLG null mutations were successfully genotyped in 423 students of which 11 (2.6%) were carriers of FLG null mutation: 1/423 (0.2%) was heterozygous for R501X and 10/423 (2.4%) were heterozygous for 2282del4. No carriers of R2447X and S3247X mutations were identified. In wild‐type FLG carriers (412 subjects), atopic dermatitis was present in 45 (11%), allergic rhinitis in 70 (17%) and allergic asthma in 29 (7%) students. Twenty‐five of 393 (7%) patch‐tested wild‐type FLG carriers had ACD. Among 11 FLG null mutation carriers, four had one or more allergic diseases, and five had reported skin symptoms without defined allergic sensitization (positive skin prick test and/or patch test). FLG null mutations were not confirmed as a predictor of analysed allergic diseases, but were confirmed as an independent predictor of skin symptoms (OR 17.19, 95% CI 3.41–86.6, P < 0.001). Our results in general indicate a low frequency of FLG null mutations in the studied Croatian population supporting a theory of a latitude‐dependent distribution of FGL null mutations in Europe, with a decreasing north–south gradient of R501X and 2282del4 mutation frequency. The relation between FLG null mutations and skin disorders was confirmed. 相似文献
998.
Snežana Minić Dušan Trpinac Heinz Gabriel Martin Gencik Miljana Obradović 《Clinical oral investigations》2013,17(1):1-8
Objectives
Incontinentia pigmenti (IP) is an X-linked genodermatosis caused by a mutation of the IKBKG gene. The objective of this study was to present a systematic review of the dental and oral types of anomalies, to determine the total number and sex distribution of the anomalies, and to analyze possible therapies.Materials and methods
We analyzed the literature data from 1,286 IP cases from the period 1993–2010.Results
Dental and/or oral anomalies were diagnosed for 54.38% of the investigated IP patients. Most of the anomaly types were dental, and the most frequent of these were dental shape anomalies, hypodontia, and delayed dentition. The most frequent oral anomaly types were cleft palate and high arched palate. IKBKG exon 4–10 deletion was present in 86.36% of genetically confirmed IP patients.Conclusions
According to the frequency, dental and/or oral anomalies represent the most frequent and important IP minor criteria. The most frequent mutation was IKBKG exon 4–10 deletion. The majority of dental anomalies and some of the oral anomalies could be corrected.Clinical relevance
Because of the presence of cleft palate and high arched palate in IP patients, these two anomalies may be considered as diagnostic IP minor criteria as well. 相似文献999.
Aleksa Marković DDS PhD José Luís Calvo‐Guirado DDS PhD MSc Zoran Lazić DDS PhD Gerardo Gómez‐Moreno DDS PhD MSc Dejan Ćalasan DDS MSc Javier Guardia DDS PhD Snježana Čolic DDS PhD Antonio Aguilar‐Salvatierra DDS Bojan Gačić DDS PhD Rafael Delgado‐Ruiz DDS PhD MSc Bojan Janjić DDS MSc Tijana Mišić DDS 《Clinical implant dentistry and related research》2013,15(3):341-349
Purpose: The aim of this study was to investigate the relationship between surgical techniques and implant macro‐design (self‐tapping/non‐self‐tapping) for the optimization of implant stability in the low‐density bone present in the posterior maxilla using resonance frequency analysis (RFA). Materials and Methods: A total of 102 implants were studied. Fifty‐six self‐tapping BlueSkyBredent® (Bredent GmbH&Co.Kg®, Senden, Germany) and 56 non‐self‐tapping Standard Plus Straumann® (Institut Straumann AG®, Waldenburg, Switzerland) were placed in the posterior segment of the maxilla. Implants of both types were placed in sites prepared with either lateral bone‐condensing or with bone‐drilling techniques. Implant stability measurements were performed using RFA immediately after implant placement and weekly during a 12‐week follow‐up period. Results: Both types of implants placed after bone condensing achieved significantly higher stability immediately after surgery, as well as during the entire 12‐week observation period compared with those placed following bone drilling. After bone condensation, there were no significant differences in primary stability or in implant stability after the first week between both implant types. From 2 to 12 postoperative weeks, significantly higher stability was shown by self‐tapping implants. After bone drilling, self‐tapping implants achieved significantly higher stability than non‐self‐tapping implants during the entire follow‐up period. Conclusions: The outcomes of the present study indicate that bone drilling is not an effective technique for improving implant stability and, following this technique, the use of self‐tapping implants is highly recommended. Implant stability optimization in the soft bone can be achieved by lateral bone‐condensing technique, regardless of implant macro‐design. 相似文献
1000.
Ricardo Walter DDS MS 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2013,25(1):72-76
Recent developed flowable composite resins have been marketed for bulk filling of preparations or replacement of dentin in a single increment. The obvious attraction of these materials—quicker placement of restorations—has rapidly made them very popular despite the limited in vitro data and lack of clinical studies. This Critical Appraisal will review some of the available in vitro literature on the topic and summarize the available knowledge in this new category of restorative materials. 相似文献