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In this paper a numerical investigation of replacement implant for partial hip arthroplasty is presented. The long-term stability of hip implants depends, among other things, on the loads acting across the joint. Forces occurring in vivo can be much greater than the recommended test values, because a typical gait cycle generates forces up to 6–7 times the body weight in the hip joint. A finite element analysis (FEA) was performed using 3-dimensional models to examine the mechanical behaviour of the femoral component at forces ranging from 2.5 to 6.3 kN. This implant design was chosen for numerical analysis because stress concentration in femoral component lead to implant fracture. Results show that the force magnitudes acting on the implant are of interest, and that they can cause implant stress field changes and implant stability problems, which can lead to implant failure. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports a precise, live cell-patterning method by means of patterning a silicon or glass substrate with alternating cytophilic and cytophobic self-assembled monolayers (SAMs) deposited via molecular vapor deposition. Specifically, a stack of hydrophobic heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane SAMs and a silicon oxide adhesion layer were patterned on the substrate surface, and a hydrophilic SAM derived from 3-trimethoxysilyl propyldiethylenetriamine was coated on the remaining non-treated areas on the substrate surface to promote cell growth. The primary characteristics of the reported method include: (i) single-cell resolution; (ii) easy alignment of the patterns with the pre-existing patterns on the substrate; (iii) easy formation of nanoscale patterns (depending on the exposure equipment); (iv) long shelf life of the substrate pattern prior to cell culturing; (v) compatibility with conventional, inverted, optical microscopes for simple visualization of patterns formed on a glass wafer; and (vi) the ability to support patterned cell (osteoblast) networks for at least 2weeks. Here, we describe the deposition technique and the characterization of the deposited layers, as well as the application of this method in the fabrication of multielectrode arrays supporting patterned neuronal networks. [Copyright &y& Elsevier]

Summary: Thyroperoxidase and galectin-3 have been reported as useful immunohistochemical markers of thyroid malignancy. In this study, we evaluated the relationship between immunohistochemical staining results for these markers and clinicopathologic features of patients with differentiated thyroid cancer. A total of 193 archival thyroid samples including 28 follicular adenomas, 18 follicular carcinomas, and 147 papillary carcinomas with 114 adjacent thyroid tissues were analyzed by immunohistochemistry. Thyroperoxidase was underexpressed (<50% stained thyrocytes), and galectin-3 was expressed (>5% stained thyrocytes) in most carcinomas. The sensitivity for diagnosis of differentiated thyroid carcinoma was 86.1% for thyroperoxidase and 82.4% for galectin-3, whereas the combination of both markers increased the sensitivity up to 94.5%. Thus, the combination of thyroperoxidase and galectin-3 immunohistochemistry may help to ascertain the malignant nature of the lesion. Furthermore, tumor size, nodal involvement, extrathyroidal invasion, and high tumor-node-metastasis stage in patients with papillary carcinoma were related to thyroperoxidase absence and high galectin-3 expression in most cases (P < .05). In patients with follicular carcinoma, the extent of invasiveness was associated with galectin-3 positivity. Thus, expression of these markers is related to more or less aggressive biological behavior of differentiated thyroid carcinomas. Although thyroperoxidase presence may indicate favorable prognosis of papillary cancer, expression of galectin-3 illustrates the potential importance of this protein in the pathogenesis and/or progression of differentiated thyroid carcinomas. [Copyright &y& Elsevier]

Abstract: This paper describes the design of a thermal inchworm device to realize precision in-package positioning. The inchworm actuation mechanism includes two metallic actuators facing each other and a workpiece between them. Electrothermal actuation is used to move the workpiece in the desired direction by inputting electric currents in a particular sequence. Nickel is chosen as the material of the actuators due to its desirable electrical, thermal and mechanical properties and availability in fabrication facilities. ANSYS theoretical modeling shows the proposed design can achieve high actuation resolution (0.1μm) with large driving force and will provide power-free latching as well. The transient analysis defines the current input sequence needed to move the workpiece. The design has been carried out for specific application to optical fiber alignment but has potential for a wide range of other applications. [Copyright &y& Elsevier]

Abstract: The micro-arheometer (micro-array of rheometers) is a multi-functional system on a chip. It is capable of cell manipulation and sorting utilizing dielectrophoresis, as well as measuring frequency-dependent viscoelastic cell properties by applying a known force with the desired frequency (piezoelectric actuation) and measuring displacement using a piezoresistive read-out. The micro-arheometer will accelerate biomedical research generating a larger statistical data set in a shorter amount of time by automating the process of micro-rheology on multiple cells at a time. [Copyright &y& Elsevier]

Abstract: Aims: The objective of the study was to report a series of patients with Hürthle cell tumours. Methods: We reviewed medical records of single institution from January 1982 to December 2002, including follow-up information. Results: We identified 199 patients with Hürthle cell tumours (HCT), 88 patients with Hürthle cell carcinoma (HCC) and 111 patients with Hürthle cell adenoma (HCA). The HCC group had significantly longer duration of the disease and larger tumours (4.8 vs 3.8cm) compared with HCA group. Gender appeared to play significant role in patients with HCT (women outnumbered man by 7:1; p<0.01). Surgical management for 80% of patients with HCA consisted of hemithyroidectomy and total thyroidectomy in 87% patients in the HCC group. Temporary laryngeal nerve palsy and temporary hypoparathyroidismus were not seen in HCA group, in HCC group were confirmed in 2.27 and 3.41%, respectively. Four patients with HCC relapsed and two died of HCC. Conclusions: HCC has outlook for favorable outcome when treated radically with total thyroidectomy. [Copyright &y& Elsevier]

VEGF is prototypic marker of neovascularization, repeatedly proposed as intrinsic characteristic of peri-implantitis. This study aimed to assess pattern of VEGF in peri-implantitis, its correlation with titanium particles (TPs) and capacity as respective biomarker. Pathological specificity of VEGF was assessed in peri-implant granulations using immunohistochemistry, periodontal granulations represented Ti-free positive controls. VEGF was correlated to TPs, identified using scanning electron microscopy coupled with dispersive x-ray spectrometry. Diagnostic accuracy, sensitivity and specificity of VEGF were estimated in PICF specimens from peri-implantitis, peri-implant mucositis (PIM) and healthy peri-implant tissues (HI) using machine learning algorithms. Peri-implantitis exhibited rich neovascular network with expressed density in contact zones toward neutrophil infiltrates without specific pattern variations around TPs, identified in all peri-implantitis specimens (mean particle size 8.9 ± 24.8 µm2; Ti-mass (%) 0.380 ± 0.163). VEGF was significantly more expressed in peri-implantitis (47,065 ± 24.2) compared to periodontitis (31,14 ± 9.15), and positively correlated with its soluble concentrations in PICF (p = 0.01). VEGF was positively correlated to all clinical endpoints and significantly increased in peri-implantitis compared to both PIM and HI, but despite high specificity (96%), its overall diagnostic capacity was average. Two patient clusters were identified in peri-implantitis, one with 8-fold higher VEGF values compared to HI, and second with lower values comparable to PIM. VEGF accurately reflects neovascularization in peri-implantitis that was expressed in contact zones toward implant surface without specific histopathological patter variation around TPs. VEGF answered requests for biomarker of peri-implantitis but further research is necessary to decrypt its exact underlying cause. [Display omitted] • Neovascularization was expressed in contact zones toward implant surface. • VEGF is highly specific to peri-implantitis and accurately reflects neovascularization. • VEGF could not be directly associated to titanium particles. • In-depth research is required to decipher the specific VEGF pattern in peri-implantitis. [ABSTRACT FROM AUTHOR]

Abstract: We present the first Romanian study on the epidemiological characteristics of MDS, based on the data existing in Fundeni Clinical Institute, Hematological Department, Bucharest. The files at diagnosis of the adult patients with primary MDS admitted during the period 1982–2005, recorded in the registration forms provided by the MDS Foundation (USA), represented the primary database. This study indicates an increase in the number of new MDS cases over the period of time investigated. Also, a 10 years lower median age of the patients, a noticeable proportion of young patients and a low proportion of patients ≥81years have been found, which situates our findings in the middle between the Eastern and Western epidemiological reported data on MDS. [Copyright &y& Elsevier]

Conventional karyotype is one of the most relevant prognostic factors in MDS. However, about 50% of patients with MDS have a normal karyotype. Usually, 20–25 normal metaphases (nMP) are considered to be optimal to exclude small abnormal clones which might be associated with poor prognosis. This study evaluated the impact of examining a suboptimal number of metaphases in patients recruited to the EUMDS Registry with low and intermediate-1 risk according to IPSS. Only 179/1049 (17%) of patients with a normal karyotype had a suboptimal number of nMP, defined as less than 20 metaphases analyzed. The outcome (overall survival and progression-free survival) of patients with suboptimal nMP was not inferior to those with higher numbers of analyzed MP both in univariate and multivariate analyses. For patients with an abnormal karyotype, 224/649 (35%) had a suboptimal number of MP assessed, but this did not impact on outcome. For patients with a normal karyotype and suboptimal numbers of analyzable metaphases standard evaluation might be acceptable for general practice, but we recommend additional FISH-analyses or molecular techniques, especially in candidates for intensive interventions. [ABSTRACT FROM AUTHOR]

Abstract: The syntheses of five novel 2-oxyalkyl-cyclohex-2-enones, structurally related to the natural products COTC and antheminone A, are described. The target structures were selected in order to probe the influence of several key structural parameters on in vitro anti-cancer bioactivity. The results of a cytotoxicity bioassay of the compounds against non-small-cell lung cancer cell lines A549 and H460 are reported. The biological data provides useful information, which will help guide the future design of compounds in this class with enhanced anti-cancer activity. [ABSTRACT FROM AUTHOR]

Abstract: Syntheses of three novel analogues of the Streptomyces metabolite COTC are described, using the versatile chiral pool starting material, (−)-quinic acid. The results of bioassays of the target compounds against two lung cancer cell lines, A549 and H460, are presented. [Copyright &y& Elsevier]