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991.
Elisa Haucke PhD Alexander Navarrete‐Santos PhD Andreas Simm PhD Rolf‐Edgar Silber MD Britt Hofmann MD 《Wound repair and regeneration》2014,22(2):239-245
The immune response during aging and diabetes is disturbed and may be due to the altered migration of immune cells in an aged tissue. Our study should prove the hypothesis that age and diabetes‐related advanced glycation end products (AGEs) have an impact on the migration and adhesion of human T‐cells. To achieve our purpose, we used in vitro AGE‐modified proteins (soluble albumin and fibronectin [FN]), as well as human collagen obtained from bypass graft. A Boyden chamber was used to study cell migration. Migrated Jurkat T‐cells were analyzed by flow cytometry and cell adhesion by crystal violet staining. Actin polymerization was determined by phalloidin‐Alexa‐fluor 488‐labeled antibody and fluorescence microscopy. We found that significantly fewer cells (50%, p = 0.003) migrated through methylglyoxal modified FN. The attachment to FN in the presence of AGE‐bovine serum albumin (BSA) was also reduced (p < 0.05). In ex vivo experiments, isolated collagen from human vein graft material negatively affected the migration of the cells depending on the grade of AGE modification of the collagen. Collagen with a low AGE level reduced the cell migration by 30%, and collagen with a high AGE level by 60%. Interaction of the cells with an AGE‐modified matrix, but not with soluble AGEs like BSA‐AGE per se, was responsible for a disturbed migration. The reduced migration was accompanied by an impaired actin polymerization. We conclude that AGEs‐modified matrix protein inhibits cell migration and adhesion of Jurkat T‐cells. 相似文献
992.
David B. Lumenta MD Eva Siepmann MD Lars‐Peter Kamolz MD PhD 《Wound repair and regeneration》2014,22(4):483-491
No universally accepted standard for evaluation, prevention, and treatment of scars, hypertrophic scars, and keloids exists. Following development of a questionnaire, we performed a closed Web‐based survey among burn centers. Server‐based data collection was performed over 4 weeks and closed thereafter. The poll revealed emerging new treatment schemes, but the majority of participants adhered to evaluation (Patient and Observer Scar Assessment Scale, Matching Assessment of Scars and Photographs, Vancouver Scar Scale, two‐dimensional photography) and prevention (silicone gel sheets and compression garments) strategies that were in line with the currently available recommendations from the literature. We noted a low penetration for the use of objective evaluation tools in our poll and detected differences in surgical approaches to keloids. Based on the results of our survey and the power of currently available clinical recommendations, we expect future guidelines to gain more evidence‐based power, especially when more high‐quality clinical trials with objective evaluation support, clearly defined disease entities, and therapeutic outcome factors have become available. 相似文献
993.
994.
Luciana da Fonseca da Silva José Pedro da Silva Aida L R Turquetto Sonia Meiken Franchi Cybelle M Cascudo Rodrigo Moreira Castro Walter José Gomes Christian Schreiber 《Brazilian Journal Of Cardiovascular Surgery》2014,29(2):123-130
Introduction
Congenital heart defects treatment shows progressive reduction in morbidity and mortality, however, the scar, resulting from ventricular (VSD) and atrial septal defect (ASD) repair, may cause discomfort. Right axillary minithoracotomy approach, by avoiding the breast growth region, is an option for correction of these defects that may provide better aesthetic results at low cost. Since October 2011, we have been using this technique for repairing VSD and ASD defects as well as associated defects.Objectives
To evaluate the efficacy of this method in children undergoing correction of VSD and ASD, to compare perioperative clinical outcomes with those repaired by median sternotomy, and to evaluate the aesthetic result.Methods
Perioperative clinical data of 25 patients submitted to axillary thoracotomy were compared with data from a paired group of 25 patients with similar heart defects repaired by median sternotomy, from October 2011 to August 2012.Results
Axillary approach was possible even in infants. There was no mortality and the main perioperative variables were similar in both groups, except for lower use of blood products in the axillary group (6/25) vs. control (13/25), with statistical difference (P =0.04). The VSD size varied from 7 to 15 mm in axillary group. Cannulation of the aorta and vena cavae was performed through the main incision, whose size ranged from 3 to 5 cm in the axillary group, with excellent aesthetic results.Conclusion
The axillary thoracotomy was effective, allowing for a heart defect repair similar to the median sternotomy, with more satisfactory aesthetic results and reduced blood transfusion, and it can be safely used in infants. 相似文献995.
Regulatory T cells (Tregs) are essential for the establishment and maintenance of immune tolerance, suggesting a potential therapeutic role for Tregs in transplantation. However, Treg administration alone is insufficient in inducing long‐term allograft survival in normal hosts, likely due to the high frequency of alloreactive T cells. We hypothesized that a targeted reduction of alloreactive T effector cells would allow a therapeutic window for Treg efficacy. Here we show that preconditioning recipient mice with donor‐specific transfusion followed by cyclophosphamide treatment deleted 70–80% donor‐reactive T cells, but failed to prolong islet allograft survival. However, infusion of either 5 × 106 Tregs with direct donor reactivity or 25 × 106 polyclonal Tregs led to indefinite survival of BALB/c islets in more than 70% of preconditioned C57BL/6 recipients. Notably, protection of C3H islets in autoimmune nonobese diabetic mice required islet autoantigen‐specific Tregs together with polyclonal Tregs. Treg therapy led to significant reduction of CD8+ T cells and concomitant increase in endogenous Tregs among graft‐infiltrating cells early after transplantation. Together, these results demonstrate that reduction of the donor‐reactive T cells will be an important component of Treg‐based therapies in transplantation. 相似文献
996.
997.
We performed a randomised comparison of the i‐gel? and the Laryngeal Mask Airway (LMA) Classic? in children aged less than a year who were undergoing general anaesthesia for elective surgery. Fifty‐four infants were randomly allocated to either the i‐gel or the LMA Classic. We measured performance characteristics, fibreoptic views through the device and complications. Success rate at first insertion attempt was 100% (27/27) in the i‐gel group compared with 88% (23/26) in the LMA Classic group. Insertion of the device was considered easy in 26/27 (96%) patients in the i‐gel group compared with 18/26 (69%) patients in the LMA Classic group (p = 0.009). There were no differences between the groups in insertion times, fibreoptic views through the device, airway leak pressures or complications. We conclude that the i‐gel was considered easier to insert than the LMA Classic in infants. 相似文献
998.
K. Pummer R. Zigeuner S. Brookman‐May W. F. Wieland H. M. Fritsche A. Aziz 《Andrologia》2014,46(2):106-111
The influence of overweight and obesity on sperm quality and reproductive hormone levels is under discussion. The aim of the present retrospective study was to evaluate the influence of body mass index (BMI) on sperm quality and reproductive hormones. We analysed semen samples and serum levels of FSH, LH, T and PRL of a total of 2110 men attending our andrology unit from 1994 to 2010 due to infertility work‐up. Patients were stratified according to their BMI in four groups. Main outcome measures were sperm motility, morphology and concentration. Serum levels of FSH, LH, T and PRL were evaluated as well. No statistically significant difference was found for sperm quality and BMI between patients categorised according to the four BMI levels. T (P < 0.001) and LH (P = 0.006) significantly differed between the four groups. In multivariable analysis, BMI did not have significantly independent influence on all assessed sperm quality parameters, whereas BMI significantly influenced hormone values for LH (P = 0.001), T (P = <0.001) and PRL (P = 0.044). We therefore conclude that BMI has no significant impact on sperm quality parameters. However, serum levels of LH, T and PRL were significantly influenced by BMI. 相似文献
999.
L.‐Y. Jiang J.‐J. Shan X.‐M. Tong H.‐Y. Zhu L.‐Y. Yang Q. Zheng Y. Luo Q.‐X. Shi S.‐Y. Zhang 《Andrologia》2014,46(8):824-830
Cystic fibrosis transmembrane conductance regulator (CFTR) has been demonstrated to be expressed in mature spermatozoa and correlated with sperm quality. Sperm CFTR expression in fertile men is higher than that in infertile men suffering from teratospermia, asthenoteratospermia, asthenospermia and oligospermia, but it is unknown whether CFTR is correlated with sperm parameters when sperm parameters are normal. In this study, 282 healthy and fertile men with normal semen parameters were classified into three age groups, group (I): age group of 20–29 years (98 cases, 27.1 ± 6.2), group (II): age group of 30–39 years (142 cases, 33.7 ± 2.6) and group (III): age group of more than or equal to 40 years (42 cases, 44.1 ± 4.6). Sperm concentration, total count and progressive motility were analysed by computer‐assisted sperm analysis. Sperm morphology was analysed by modified Papanicolaou staining. Sperm CFTR expression was conducted by indirect immunofluorescence staining. There was a significant positive correlation (P < 0.001) between CFTR expression and sperm progressive motility (r = 0.221) and normal morphology (r = 0.202), but there were no correlations between sperm CFTR expression and semen volume, sperm concentration, sperm total count as well as male age (P > 0.05). Our findings show that CFTR expression is associated with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters, but not associated with the number of spermatozoa and male age. 相似文献
1000.
S. Karabulut A. Demiroğlu‐Zergeroğlu E. Yılmaz F. Sağır N. Delikara 《Andrologia》2014,46(10):1113-1117
Sperm or testicular tissue cryopreservation is performed in cases of male infertility as a treatment for the preservation of fertility. When these sperm cells are used in assisted reproductive techniques, fertilisation rates, developmental and implantation potential of embryos decrease and the abortion rates increase. In the present work, differences of both phosphorylation and expression levels of p53 and Mitogen‐activated protein kinases (MAPK) proteins were analysed in 61 individual sperm samples before and after cryopreservation. We observed that p53 protein residue at Ser 15 was phosphorylated after cryopreservation. Because MAPK pathway activations may be involved in p53 phosphorylation, MAPK/ERK, Stress‐activated protein kinases (SAPK)/JNK and p38MAPK proteins were also investigated. Analysis showed that p38MAPK phosphorylations increased significantly. However, ERK and JNK expressions and phosphorylations decreased, although the differences were not statistically significant. According to our results, it may be suggested that cryopreservation process activates p53 via p38 MAPK pathway that subsequently causes apoptosis, which may be related to sperm parameters. 相似文献