Syndecans are cell surface proteoglycans that bind and modulate various proinflammatory mediators and can be proteolytically shed from the cell surface. Within the lung, syndecan-1 and -4 are expressed as transmembrane proteins on epithelial cells and released in the bronchoalveolar fluid during inflammation. We here characterize the mechanism leading to the generation of soluble syndecan-1 and -4 in cultured epithelial cells and murine lung tissue. We show that the bladder carcinoma epithelial cell line ECV304, the lung epithelial cell line A459 and primary alveolar epithelial cells express and constitutively release syndecan-1 and -4. This release involves the activity of the disintegrin-like metalloproteinase ADAM17 as demonstrated by use of specific inhibitors and lentivirally transduced shRNA. Stimulation of epithelial cells with PMA, thrombin, or proinflammatory cytokines (TNF␣/IFN␥) led to the down-regulation of surface-expressed syndecan-1 and -4, which was associated with a significant increase of soluble syndecans and cell-associated cleavage fragments. The enhanced syndecan release was not related to gene induction of syndecans or ADAM17, but rather due to increased ADAM17 activity. Soluble syndecan-1 and -4 were also released into the bronchoalveolar fluid of mice. Treatment with TNF␣/IFN␥ increased ADAM17 activity and syndecan release in murine lungs. Both constitutive and induced syndecan shedding was prevented by the ADAM17 inhibitor. ADAM17 may therefore be an important regulator of syndecan functions on inflamed lung epithelium.Syndecans are a family of cell surface proteoglycans that play regulatory roles in wound healing, inflammation, angiogenesis, and neuronal patterning. There are four members of the syndecan family (syndecan-1, -2, -3, and -4) each consisting of an ectodomain carrying heparan sulfate-or chondroitin sulfaterich glucosaminoglycan chains, a transmembrane domain, and a short cytoplasmic tail (1). Syndecan-1 is predominantly found on endothelial and epithelial cells whereas syndecan-4 is ubiquitously expressed (2). Syndecans are also released as soluble variants that have been found in various body fluids including serum of cancer patients, wound fluid, or bronchoalveolar fluid of inflamed lungs (3-7).Recent research with syndecan-1 Ϫ/Ϫ and syndecan-4mice has demonstrated that syndecans play an important role in the regulation of inflammation and wound healing (1). Syndecans act as coreceptors modulating binding and signaling of cytokines, chemokines, and adhesion molecules. Syndecan-1 deficiency results in increased acute lung inflammation. Syndecan-1 cleavage by matrix metalloproteinase 7 (MMP7) 2 helps to establish a gradient for the chemokine KC guiding transepithelial migration of neutrophils into the airway (8). These activities can be partially reversed by soluble syndecans competing with transmembrane syndecans for their extracellular ligands (9). Soluble syndecans are generated by proteolytic shedding at the cell surface (4, 10, 11). A basal shedding activity results i...
One major criterion for dental age estimation is the evaluation of third molar mineralization. There are various methods for evaluating tooth mineralization based on classification by stages. The aim of the present work is to assess the validity of the common classification systems. To this end, we analyzed 420 conventional orthopantomograms of German females aged 12-25 years old. The mineralization status of tooth 38 was determined using the stages defined by Gleiser and Hunt, Demirjian et al., Gustafson and Koch, Harris and Nortje and Kullman et al., respectively. Of the methods tested, the most accurate results were obtained with Demirjian et al.'s classification system, which performed best not only for observer agreement but also for the correlation between estimated and true age. It is argued that this is due to the fact that Demirjian et al.'s classification is based on a sufficient number of stages which are defined independently of speculative estimations of length. This leads to the conclusion that the method devised by Demirjian et al. should be used for evaluating the mineralization of third molars for purposes of forensic age determination.
Background and aimsHelicobacter pylori is the causative agent of gastric diseases and the main risk factor in the development of gastric adenocarcinoma. In vitro studies with this bacterial pathogen largely rely on the use of transformed cell lines as infection model. However, this approach is intrinsically artificial and especially inappropriate when it comes to investigating the mechanisms of cancerogenesis. Moreover, common cell lines are often defective in crucial signalling pathways relevant to infection and cancer. A long-lived primary cell system would be preferable in order to better approximate the human in vivo situation.MethodsGastric glands were isolated from healthy human stomach tissue and grown in Matrigel containing media supplemented with various growth factors, developmental regulators and apoptosis inhibitors to generate long-lasting normal epithelial cell cultures.ResultsCulture conditions were developed which support the formation and quasi-indefinite growth of three dimensional (3D) spheroids derived from various sites of the human stomach. Spheroids could be differentiated to gastric organoids after withdrawal of Wnt3A and R-spondin1 from the medium. The 3D cultures exhibit typical morphological features of human stomach tissue. Transfer of sheared spheroids into 2D culture led to the formation of dense planar cultures of polarised epithelial cells serving as a suitable in vitro model of H. pylori infection.ConclusionsA robust and quasi-immortal 3D organoid model has been established, which is considered instrumental for future research aimed to understand the underlying mechanisms of infection, mucosal immunity and cancer of the human stomach.
The authors retrospectively analyzed 629 CT images of patients aged between 15 and 30 years produced during multiple trauma diagnostics at the Unfallkrankenhaus Berlin. For the purposes of this study, the authors reliably determined the ossification status of the medial epiphysis of the clavicle in 556 cases, using the classification of stages by Schmeling et al. In both sexes, stage 2 was first noted at age 15. In male patients, the earliest occurrence of stage 3 was noted at age 17, in female patients at age 16. Stage 4 was first achieved by both sexes at age 21. Stage 5 was first noted in female patients at age 21 and in male patients at age 22, which is 4 or 5 years earlier than was observed by a comparable study using conventional radiographs. The partial-volume effect in computed tomography using the thick slice scanning mode was discussed as a possible explanation for this early visualization. The question of how slice thickness affects the age intervals between ossification stages identified by CT examinations should be examined in additional studies.
Thin-slice computed tomography provides the imaging modality of choice in analysing the ossification process of the medial clavicular epiphysis for the purpose of forensic age diagnostics in the living in the course of criminal proceedings. The classification of the ossification stages by Schmeling et al. compass the emergence of an epiphyseal ossification centre (stage 2), the partial fusion of the epiphysis with the metaphysis (stage 3), the complete fusion of these osseous elements including a visible epiphyseal scar (stage 4), and the complete fusion without a visible epiphyseal scar (stage 5). In the present study, each of the ossification stages 2 and 3 was divided into an early, intermediate and late phase. The authors evaluated the thin-slice CT scans of 185 patients aged between 13 and 26 years. In all these cases, a stage 2 or 3 had been determined in a previous study. The late stage 3, which is characterized by a fusion between metaphysis and epiphysis completing more than two thirds of the former epiphyseal gap, first appeared at age 19 in both sexes. If a late stage 3 is found, it is therefore possible to substantiate that an individual has already reached the legally important age threshold of 18 years.
Summary Chronic allograft injury (CAI) is the most common cause of graft failure after the first year of transplantation. To date, only protocol biopsies can reveal subclinical disease. Transient elastography (TE) is a novel noninvasive technique that has demonstrated high reliability in the assessment of liver fibrosis. This study evaluates the feasibility of TE for the assessment of renal allograft fibrosis. Fifty‐seven patients underwent TE by the FibroScan® device. Biopsies were performed in 20 patients. Measurement of parenchymal stiffness by TE was successful in 55 of 57 patients (96.5%). Stiffness was significantly correlated to the extent of interstitial fibrosis (Pearson r: 0.67, P: 0.002, R2: 0.45) and inversely related to estimated glomerular filtration rate (eGFR) (Pearson r: −0.47, P: 0.0003, R2: 0.22). Stiffness values of patients with an eGFR >50 ml/min were significantly lower than in patients with an eGFR ≤50 ml/min (22.2 ± 11.0 vs. 37.1 ± 14.2 kPa, P: 0.0005). The stiffness values of CAI Banff grades 0–1 differed significantly from grade 2 (P: 0.008) and grade 3 (P: 0.046). Parenchymal stiffness measured by TE reflects interstitial fibrosis in kidney allografts. A longitudinal assessment of parenchymal stiffness might be a powerful tool to identify patients with CAI who benefit from biopsy and consequent adaptation of the immunosuppressive regime.
Intravenous methylprednisolone administration before hepatic resection significantly reduced systemic inflammatory cytokine release. No adverse effect on immunity was noted due to the methylprednisolone. We found no significant difference in the convalescence score, but a significantly shorter hospital stay in the steroid group. Further studies with more patients are needed to elucidate the clinical impact of preoperative steroid bolus therapy in liver surgery.
Determination of the stage of ossification of the medial clavicular epiphysis is a crucial part of age estimation in criminal proceedings when evaluating individuals with completed hand ossification. In order to ensure a maximum of accuracy in forensic age estimation practise, it is recommended to perform thin-slice CT scans; but to date there exist no reference data on the bone development of the region in question based on thin-slice computed tomography. In this retrospective study, the authors evaluated thin-slice multidetector CT images of 592 individuals aged between 10 and 35 years produced in the University Hospital of Münster. The ossification status of the medial epiphysis of the clavicle could be reliably determined in 502 cases using the classification of stages by Schmeling et al. In male individuals, stage 2 was first noted at age 14, in female individuals at age 13. Stage 3 was first achieved by male individuals at age 17, by female individuals at age 16. The occurrence of stage 4 was first found in both sexes at the age of 21. In either sex, the earliest observation of stage 5 was at age 26. The findings are basically in line with those from the only CT-based study on the subject in question using the same classification of five stages, except from the fact that in the present study, stage 5 first occurs at age 26, which is 4 or 5 years later than what was found in the CT study using 7 mm slices in the majority of cases. This vast difference may be explained through the partial volume effect occurring with thick-slice CT images by a visual deception of the epiphyseal scar occurring with stage 4.
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