Novel Insights into the Treatment of Complicated Diverticulitis

In this thesis, novel insights into the treatment of the different entities of complicated diverticulitis are described. Moreover, results of research into the treatment and incidence of stoma-related complications are presented

Chorioallantoic membrane assay as model for angiogenesis in tissue engineering : focus on stem cells

Tissue engineering aims to structurally and functionally regenerate damaged tissues, which requires the formation of new blood vessels that supply oxygen and nutrients by the process of angiogenesis. Stem cells are a promising tool in regenerative medicine due to their combined differentiation and paracrine angiogenic capacities. The study of their proangiogenic properties and associated potential for tissue regeneration requires complex in vivo models comprising all steps of the angiogenic process. The highly vascularized extraembryonic chorioallantoic membrane (CAM) of fertilized chicken eggs offers a simple, easy accessible, and cheap angiogenic screening tool compared to other animal models. Although the CAM assay was initially primarily performed for evaluation of tumor growth and metastasis, stem cell studies using this model are increasing. In this review, a detailed summary of angiogenic observations of different mesenchymal, cardiac, and endothelial stem cell types and derivatives in the CAM model is presented. Moreover, we focus on the variation in experimental setup, including the benefits and limitations of in ovo and ex ovo protocols, diverse biological and synthetic scaffolds, imaging techniques, and outcome measures of neovascularization. Finally, advantages and disadvantages of the CAM assay as a model for angiogenesis in tissue engineering in comparison with alternative in vivo animal models are described

Avulsie van bovenfrontelementen in het definitieve gebit, schade na reïmplantatie: een paradigmashift.

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Pleiotropic effects of a rel mutation on stress survival of Rhizobium etli CNPAF512

The rel gene of Rhizobium etli (relRet), the nodulating endosymbiont of the common bean plant, determines the cellular level of the alarmone (p)ppGpp and was previously shown to affect free-living growth and symbiosis. Here, we demonstrate its role in cellular adaptation and survival in response to various stresses.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Cost-effectiveness of sigmoid resection with primary anastomosis or end colostomy for perforated diverticulitis: an analysis of the randomized Ladies trial

Background: Several studies have been published favouring sigmoidectomy with primary anastomosis over Hartmann's procedure for perforated diverticulitis with purulent or faecal peritonitis (Hinchey grade III or IV), but cost-related outcomes were rarely reported. The present study aimed to evaluate costs and cost-effectiveness within the DIVA arm of the Ladies trial. Methods: This was a cost-effectiveness analysis of the DIVA arm of the multicentre randomized Ladies trial, comparing primary anastomosis over Hartmann's procedure for Hinchey grade III or IV diverticulitis. During 12-month follow-up, data on resource use, indirect costs (Short Form Health and Labour Questionnaire) and quality of life (EuroQol Five Dimensions) were collected prospectively, and analysed according to the modified intention-to-treat principle. Main outcomes were incremental cost-effectiveness (ICER) and cost–utility (ICUR) ratios, expressed as the ratio of incremental costs and the incremental probability of being stoma-free or incremental quality-adjusted life-years respectively. Results: Overall, 130 patients were included, of whom 64 were allocated to primary anastomosis (46 and 18 with Hinchey III and IV disease respectively) and 66 to Hartmann's procedure (46 and 20 respectively). Overall mean costs per patient were lower for primary anastomosis (€20 544, 95 per cent c.i. 19 569 to 21 519) than Hartmann's procedure (€28 670, 26 636 to 30 704), with a mean difference of €–8126 (–14 660 to –1592). The ICER was €–39 094 (95 per cent bias-corrected and accelerated (BCa) c.i. –1213 to –116), indicating primary anastomosis to be more cost-effective. The ICUR was €–101 435 (BCa c.i. –1 113 264 to 251 840). Conclusion: Primary anastomosis is more cost-effective than Hartmann's procedure for perforated diverticulitis with purulent or faecal peritonitis

Label-free mapping of microstructural organisation in self-aligning cellular collagen hydrogels using image correlation spectroscopy

Hydrogels have emerged as promising biomaterials for regenerative medicine. Despite major advances, tissue engineers have faced challenges in studying the complex dynamics of cellmediated hydrogel remodelling. Second harmonic generation (SHG) microscopy has been a pivotal tool for non-invasive visualization of collagen type I hydrogels. By taking into account the typical polarization SHG effect, we recently proposed an alternative image correlation spectroscopy (ICS) model to quantify characteristics of randomly oriented collagen fibrils. However, fibril alignment is an important feature in many tissues that needs to be monitored for effective assembly of anisotropic tissue constructs. Here we extended our previous approach to include the orientation distribution of fibrils in cellular hydrogels and show the power of this model in two biologically relevant applications. Using a collagen hydrogel contraction assay, we were able to capture cell-induced hydrogel modifications at the microscopic scale and link these to changes in overall gel dimensions over time. After 24 h, the collagen density was about 3 times higher than the initial density, which was of the same order as the decrease in hydrogel area. We also showed that the orientation parameters recovered from our automated ICS model match values obtained from manual measurements. Furthermore, regions axial to cellular processes aligned at least 1.5 times faster compared with adjacent zones. Being able to capture minor temporal and spatial changes in hydrogel density and collagen fibril orientation, we demonstrated the sensitivity of this extended ICS model to deconstruct a complex environment and support its potential for tissue engineering research

Accuracy of linear measurements using three imaging modalities: two lateral cephalograms and one 3D model from CBCT data

SummaryBackground: The aim of this study was to evaluate the accuracy of linear measurements on three imaging modalities: lateral cephalograms from a cephalometric machine with a 3 m source-to-mid-sagittal-plane distance (SMD), from a machine with 1.5 m SMD and 3D models from cone-beam computed tomography (CBCT) data. Methods: Twenty-one dry human skulls were used. Lateral cephalograms were taken, using two cephalometric devices: one with a 3 m SMD and one with a 1.5 m SMD. CBCT scans were taken by 3D Accuitomo® 170, and 3D surface models were created in Maxilim® software. Thirteen linear measurements were completed twice by two observers with a 4 week interval. Direct physical measurements by a digital calliper were defined as the gold standard. Statistical analysis was performed. Results: Nasion-Point A was significantly different from the gold standard in all methods. More statistically significant differences were found on the measurements of the 3 m SMD cephalograms in comparison to the other methods. Intra- and inter-observer agreement based on 3D measurements was slightly better than others. Limitations: Dry human skulls without soft tissues were used. Therefore, the results have to be interpreted with caution, as they do not fully represent clinical conditions. Conclusions: 3D measurements resulted in a better observer agreement. The accuracy of the measurements based on CBCT and 1.5 m SMD cephalogram was better than a 3 m SMD cephalogram. These findings demonstrated the linear measurements accuracy and reliability of 3D measurements based on CBCT data when compared to 2D techniques. Future studies should focus on the implementation of 3D cephalometry in clinical practic

Therapeutic Potential of Dental Pulp Stem Cells and Leukocyte- and Platelet-Rich Fibrin for Osteoarthritis.

Osteoarthritis (OA) is a degenerative and inflammatory joint disorder with cartilage loss. Dental pulp stem cells (DPSCs) can undergo chondrogenic differentiation and secrete growth factors associated with tissue repair and immunomodulation. Leukocyte- and platelet-rich fibrin (L-PRF) emerges in regenerative medicine because of its growth factor content and fibrin matrix. This study evaluates the therapeutic application of DPSCs and L-PRF in OA via immunomodulation and cartilage regeneration. Chondrogenic differentiation of DPSCs, with or without L-PRF exudate (ex) and conditioned medium (CM), and of bone marrow-mesenchymal stem cells was compared. These cells showed differential chondrogenesis. L-PRF was unable to increase cartilage-associated components. Immature murine articular chondrocytes (iMACs) were cultured with L-PRF ex, L-PRF CM, or DPSC CM. L-PRF CM had pro-survival and proliferative effects on unstimulated and cytokine-stimulated iMACs. L-PRF CM stimulated the release of IL-6 and PGE2, and increased MMP-13, TIMP-1 and IL-6 mRNA levels in cytokine-stimulated iMACs. DPSC CM increased the survival and proliferation of unstimulated iMACs. In cytokine-stimulated iMACs, DPSC CM increased TIMP-1 gene expression, whereas it inhibited nitrite release in 3D culture. We showed promising effects of DPSCs in an in vitro OA model, as they undergo chondrogenesis in vitro, stimulate the survival of chondrocytes and have immunomodulatory effects

Laparoscopic lavage for Hinchey III perforated diverticulitis:factors for treatment failure in two randomized clinical trials

BACKGROUND: The Scandinavian Diverticulitis (SCANDIV) trial and the LOLA arm of the LADIES trial randomized patients with Hinchey III perforated diverticulitis to laparoscopic peritoneal lavage or sigmoid resection. The aim of this analysis was to identify risk factors for treatment failure in patients with Hinchey III perforated diverticulitis.METHODS: This was a post hoc analysis of the SCANDIV trial and LOLA arm. Treatment failure was defined as morbidity requiring general anaesthesia (Clavien-Dindo grade IIIb or higher) within 90 days. Age, sex, BMI, ASA fitness grade, smoking status, previous episodes of diverticulitis, previous abdominal surgery, time to surgery, and surgical competence were all tested in univariable and multivariable logistic regression analyses using an interaction variable.RESULTS: The pooled analysis included 222 patients randomized to laparoscopic lavage and primary resection (116 and 106 patients respectively). Univariable analysis found ASA grade to be associated with advanced morbidity in both groups, and the following factors in the laparoscopic lavage group: smoking, corticosteroid use, and BMI. Significant factors for laparoscopic lavage morbidity in multivariable analysis were smoking (OR 7.05, 95 per cent c.i. 2.07 to 23.98; P = 0.002) and corticosteroid use (OR 6.02, 1.54 to 23.51; P = 0.010).CONCLUSION: Active smoking status and corticosteroid use were risk factors for laparoscopic lavage treatment failure (advanced morbidity) in patients with perforated diverticulitis