Local Magnetic Properties of Antiferromagnetic FeBr2

The antiferromagnet FeBr2 has been studied by Mössbauer spectroscopy in external fields both in the metamagnetic region below the multicritical temperature TMCP and in the second-order transition region above. The local magnetization shows that the metamagnetic transition occurs by spin flips, as in simple models. However, in the second-order transition region, the local magnetization of the sublattice oriented antiparallel to the external field varies continuously but remains parallel to the c axis. This can only be understood if the external magnetic field induces strong transversal spin precession of the moments on the antiparallel sublattice. This shows that the anomalous maxima in the imaginary part χ\u27\u27 recently found in the ac susceptibility [M.M. Pereira de Azevedo et al., J. Magn. Magn. Mater. 140-144, 1557 (1995)] and denoted H_ below the critical field HC(T), and H+ above, can be understood as being caused by noncritical transversal spin fluctuations

Poor prognostic clinicopathologic features correlate with VEGF expression but not with PTEN expression in squamous cell carcinoma of the larynx

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to assess the relationship between expression of vascular endothelial growth factor (VEGF) and phosphatase and tensin homolog deleted in chromosome ten (PTEN), angiogenesis and clinicopathological parameters of squamous cell carcinoma of the larynx.</p> <p>Methods</p> <p>We examined immunohistochemical expression of VEGF and PTEN and CD34 for microvessel density (MVD) in sections of formalin-fixed, paraffin embedded tissue blocks of 140 patients with squamous cell carcinoma of the larynx. The intensity of VEGF and PTEN staining and the proportion of cells staining were scored.</p> <p>Results</p> <p>The tumor grade was not significantly related to PTEN expression, but it was to VEGF expression (p = 0.400; p = 0.015, respectively). While there was no significant relationship between PTEN expression and tumor size and cartilage invasion (p = 0.311, p = 0.128), there was a significant relationship between the severity of VEGF expression and tumor size (p = 0.006) and lymph node metastasis (p = 0.048) but not cartilage invasion (p = 0.129). MVD was significantly higher in high-grade tumors (p = 0.003) but had no significant relationship between MVD, lymph node metastasis, and cartilage invasion (p = 0.815, p = 0.204). There was also no significant relationship between PTEN and VEGF expression (p = 0.161) and between PTEN and VEGF expression and the MVD (p = 0.120 and p = 0.175, respectively).</p> <p>Conclusions</p> <p>Increased VEGF expression may play an important role in the outcome of squamous cell carcinoma of the larynx. PTEN expression was not related to VEGF expression and clinicopathological features of squamous cell carcinoma of the larynx.</p

The use of mesenchymal stem cells for cartilage repair and regeneration: a systematic review.

BACKGROUND: The management of articular cartilage defects presents many clinical challenges due to its avascular, aneural and alymphatic nature. Bone marrow stimulation techniques, such as microfracture, are the most frequently used method in clinical practice however the resulting mixed fibrocartilage tissue which is inferior to native hyaline cartilage. Other methods have shown promise but are far from perfect. There is an unmet need and growing interest in regenerative medicine and tissue engineering to improve the outcome for patients requiring cartilage repair. Many published reviews on cartilage repair only list human clinical trials, underestimating the wealth of basic sciences and animal studies that are precursors to future research. We therefore set out to perform a systematic review of the literature to assess the translation of stem cell therapy to explore what research had been carried out at each of the stages of translation from bench-top (in vitro), animal (pre-clinical) and human studies (clinical) and assemble an evidence-based cascade for the responsible introduction of stem cell therapy for cartilage defects. This review was conducted in accordance to PRISMA guidelines using CINHAL, MEDLINE, EMBASE, Scopus and Web of Knowledge databases from 1st January 1900 to 30th June 2015. In total, there were 2880 studies identified of which 252 studies were included for analysis (100 articles for in vitro studies, 111 studies for animal studies; and 31 studies for human studies). There was a huge variance in cell source in pre-clinical studies both of terms of animal used, location of harvest (fat, marrow, blood or synovium) and allogeneicity. The use of scaffolds, growth factors, number of cell passages and number of cells used was hugely heterogeneous. SHORT CONCLUSIONS: This review offers a comprehensive assessment of the evidence behind the translation of basic science to the clinical practice of cartilage repair. It has revealed a lack of connectivity between the in vitro, pre-clinical and human data and a patchwork quilt of synergistic evidence. Drivers for progress in this space are largely driven by patient demand, surgeon inquisition and a regulatory framework that is learning at the same pace as new developments take place

ICAR: endoscopic skull‐base surgery

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A survey of cross-infection control procedures: knowledge and attitudes of Turkish dentists

OBJECTIVES: The objective of this study was to investigate the knowledge, attitudes and behavior of Turkish dentists in Samsun City regarding cross-infection control. MATERIAL AND METHODS: A questionnaire was designed to obtain information about procedures used for the prevention of cross-infection in dental practices and determine the attitudes and perceptions of respondent dental practitioners to their procedures. The study population included all dentists in the city of Samsun, Turkey, in April 2005 (n=184). The questionnaire collected data on sociodemographic characteristics, knowledge and practice of infection control procedures, sterilization, wearing of gloves, mask, use of rubber dam, method of storing instruments and disposal methods of contaminated material, etc. Questionnaire data was entered into a computer and analyzed by SPSS statistical software. RESULTS: From the 184 dentists to whom the questionnaires were submitted, 135 participated in the study (overall response rate of 73.36%). As much as 74.10% dentists expressed concern about the risk of cross-infection from patients to themselves and their dental assistants. Forty-three percent of the participants were able to define "cross-infection" correctly. The greatest majority of the respondents (95.60%) stated that all patients have to be considered as infectious and universal precautions must apply to all of them. The overall responses to the questionnaire showed that the dentists had moderate knowledge of infection control procedures. CONCLUSIONS: Improved compliance with recommended infection control procedures is required for all dentists evaluated in the present survey. Continuing education programs and short-time courses about cross-infection and infection control procedures are suitable to improve the knowledge of dentists