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91.

Objectives

The present study aims to investigate the relevance of immunohistochemical p53 expression in carcinomas of the oral cavity and of the head and neck region. Long-term clinical and histopathological follow-up findings as well as HPV status are correlated with the results of this examination.

Materials and methods

Sections made from two tissue arrays composed of 222 oral squamous cell carcinomas and 427 squamous cell carcinomas of the head and neck region, respectively, were examined for p53 expression and Ki-67 index by means of immunohistochemistry. Correlation of long-term clinical findings of the patients and pathological features of tumours with laboratory results were examined statistically.

Results

No significant correlation was found between the p53 immunohistochemical expression in the 207 oral carcinomas and features of the tumours and patient outcomes. There was no significant association between the Ki-67 labelling index and the p53 expression.

Discussion

Our failure in detecting any association of the p53 immunohistochemical expression regardless of HPV status with clinical features of these tumours suggests it lacks a prognostic value for squamous cell carcinomas of the oral cavity.

Clinical relevance

The prognostic value of p53 immunostaining in oral squamous carcinoma is not clarified yet. In the present study, there is no impact on any prognostical item nor even a correlation with cell proliferation (Ki-67) regardless of HPV status.  相似文献   
92.
93.
Polypropylene (PP) surgical mesh, used successfully for the surgical repair of abdominal hernias, is associated with serious clinical complications when used in the pelvic floor for repair of stress urinary incontinence or support of pelvic organ prolapse. While manufacturers claim that the material is inert and non-degradable, there is a growing body of evidence that asserts PP fibres are subject to oxidative damage and indeed explanted material from patients suffering with clinical complications has shown some evidence of fibre cracking and oxidation. It has been proposed that a pathological cellular response to the surgical mesh contributes to the medical complications; however, the mechanisms that trigger the specific host response against the material are not well understood. Specifically, this study was constructed to investigate the mechano–chemical effects of oxidation and dynamic distension on polypropylene surgical mesh. To do this we used a novel advanced spectroscopical characterisation technique, secondary electron hyperspectral imaging (SEHI), which is based on the collection of secondary electron emission spectra in a scanning electron microscope (SEM) to reveal mechanical–chemical reactions within PP meshes.

The application of novel SEM-based spectroscopical characterisation techniques reveals the mechano–chemical effects of oxidation and dynamic distension on polypropylene surgical mesh.  相似文献   
94.
Monatsschrift Kinderheilkunde - Eine adäquate Energie- und Nährstoffversorgung ist Grundlage für ein gesundes Wachstum und Voraussetzung für die Erhaltung von Gesundheit und...  相似文献   
95.
Solid tumors exhibit an inversed pH gradient with increased intracellular pH (pHi) and decreased extracellular pH (pHe). This inside-out pH gradient is generated via sodium/hydrogen antiporter 1, vacuolar-type H + ATPases, monocarboxylate transporters, (bi)carbonate (co)transporters and carboanhydrases. Our knowledge on how pHe-signals are sensed and what the respective receptors induce inside cells is scarce. Some pH-sensitive receptors (GPR4, GPR65/TDAG8, GPR68/OGR1, GPR132/G2A, possibly GPR31 and GPR151) and ion channels (acid-sensing ion channels ASICs, transient receptor potential vanilloid receptors TRPVs) transduce signals inside cells. As little is known on the expression and function of these pH sensors, we used immunostainings to study tissue samples from common and rare skin cancers. Our current and future work is directed towards investigating the impact of all the pH-sensing receptors in different skin tumors using cell culture techniques with selective knockdown/knockout (siRNA/CRISPR-Cas9). To study cell migration and proliferation, novel impedance-based wound healing assays have been developed and are used. The field of pH sensing in tumors and wounds holds great promise for the development of pH-targeting therapies, either against pH regulators or sensors to inhibit cell proliferation and migration.  相似文献   
96.
Neurocritical Care - Inflammatory response is the hallmark of secondary brain injury in stroke patients. Neutrophil-to-lymphocyte ratio (NLR) emerged as a marker for functional outcome in several...  相似文献   
97.
European Archives of Oto-Rhino-Laryngology - Hearing performance data was collected from a large heterogeneous group of subjects implanted with the Cochlear™ Nucleus® CI532 with Slim...  相似文献   
98.
99.
Sporadic inclusion body myositis (sIBM) contains non-necrotic myofibers that are surrounded and/or invaded by inflammatory cells. In this study we aimed to identify selective molecules that are present at this site. Myofibers of four biopsies of sIBM that were surrounded and/or invaded by inflammatory cells were microdissected, pooled and profiled by proteomic studies using mass spectrometry. Normal skeletal muscle tissue served as control. Based on the table of proteins that were detected in sIBM only, we selected nine extracellular matrix molecules and validated the results performing immunofluorescence. Seven out of nine proteins that were detected in sIBM by mass spectrometry showed different immunohistochemical results in myositis and normal controls. Of these, the small leucine-rich repeat proteins proline arginine-rich end leucine-rich repeat protein (PRELP) and biglycan were deposited precisely at myofibers surrounded and/or invaded by inflammatory cells both in sIBM and polymyositis. The basement membrane (BM) molecules merosin, perlecan, nidogen-2 and collagen IV were variably destroyed or increased at these sites. P component, which ensheathed all myofibers in normal controls, was absent from invaded myofibers. Similar to BM remodeling, the specific deposition of PRELP and biglycan may represent a mechanism to defend against immune attack. Loss of P component may affect the anchorage of the myofiber in the endomysium.  相似文献   
100.
Abstract

Aim: Undergraduate medical education is currently in a fundamental transition towards competency-based programs around the globe. A major curriculum reform implies a dual challenge: the change of the curriculum and the delivering organization. Both are closely interwoven. In this article, we provide practical insights into our approach of managing such a fundamental reform of the large undergraduate medical program at the Charité – Universitätsmedizin Berlin.

Methods: Members of the project management team summarized the key features of the process with reference to the literature.

Results: Starting point was a traditional, discipline-based curriculum that was reformed into a fully integrated, competency-based program. This change process went through three phases: initiation, curriculum development and implementation, and sustainability. We describe from a change management perspective, their main characteristics, and the approaches that were employed to manage them successfully.

Conclusions: Our report is intended to provide practical insights and guidance for those institutions which are yet considering or have already started to undergo a major reform of their undergraduate programs towards competency medical education.  相似文献   
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