Multiple cystic echinococcosis mimicking metastatic malignancy

AbstractCystic echinococcosis is seen worldwide. Considerable public health problems are encountered in endemic areas, such as South and Central America, the Middle East, sub-Saharan Africa, Russia, China, Australia and New Zealand. We have presented a case of innumerable cystic echinococcosis of lung and liver. The multiple lesions of cystic echinococcosis in chest X-ray graphy can imitate the metastatic malignancy of lung

Faun Tail Nevus and Spinal Dysraphism: Cosmetic Improvement with Alexandrite Laser Epilation

Faun-tail presents as an abnormal lumbosacral hypertrischosis and may be associated with spinal dysrasphism. In addition to the problems due to spinal anomalies, patient's physico-social life may also be affected. Here, we report a case of 13 years old female patient with Faun-tail in association with sypinal dysraphism, in which cosmetic improvement was achieved with the help of Alexandrite laser. Alexandrite laser can be the method of choice for permanent hair removal method due to its safe, effective and easy to apply properties

Dynamic fracture analysis of functionally graded materials using ordinary state-based peridynamics

Functionally graded materials are regarded as a special kind of composites capable of eliminating material interfaces and the delamination problems. Stress discontinuity can be avoided owing to smooth composition of the functionally graded ingredients. In this study, a recently emerged effective non-local continuum theory for solving fracture problems in solids and structures, peridynamics, is employed to simulate dynamic wave propagation as well as crack propagation in functionally graded materials. Specifically, the ordinary state-based formulation is adopted. The ordinary state-based formulation is slightly modified for the modelling of functionally graded materials. The averaging technique is employed to determine peridynamic parameters associated with the material properties. Firstly, a benchmark problem is considered to validate the present implementation of ordinary state-based peridynamics for brittle fracture of homogeneous materials. Then, the wave propagation in the functionally graded materials under impact loading is simulated. Finally, dynamic crack propagation in the functionally graded materials is studied. The evaluated crack paths and the displacement waves are compared with reference works including numerical and experimental results. Good agreement between the reference and present results is achieved. It is shown that a simple modification of ordinary state-based formulation has led to simulate dynamic fracture of functionally graded materials

Dynamic crack arrest analysis by ordinary state-based peridynamics

Dynamic fracture analysis for the crack arrest phenomenon is performed by ordinary state-based peridynamics formulation and discretization employing transition bond concept. Double cantilever beam specimen is chosen for our numerical evidence purpose. The analysis consists of two main phases namely, generation and application (prediction) phases. In the generation phase, the dynamic stress intensity factors of propagating and arrested cracks are estimated by the present formulation for given crack path histories, and good agreement is achieved. As for the application phase, dynamic stress intensity factors well as total crack lengths after crack arrests are in good agræment with the experiments. Moreover, the influence of transition bond concept on the crack arrest behavior is investigated and it is found that the transition bond is very efficient in the simulation of the crack arrest problem such that premature arrests of cracks are observed without transition bond cases

Mechanical analyses of flat sheet water treatment membranes

In this work, we address the mechanical response of the flat sheet polymeric water treatment membranes under the assumed operational loading conditions. Firstly, we perform quasi-static analyses of the membranes under normal pressure loads, which is the condition that resembles the actual loading for flat sheet membranes in the submerged membrane bioreactors. Then, the long-term deformation of the membranes is studied under the assumed filtration durations for the same loading conditions by utilizing the viscoelastic material models. The quasi-static and viscoelastic membrane simulations are performed by a commercial finite element code ANSYS. Finally, the mechanical fatigue life predictions are carried out based on the stress distributions from the quasi-static analyses and the long-term effects from the viscoelastic analyses

Examination of the effect of xenogeneic mesenchymal stem cells and conditioned medium on cartilage graft viability: a rabbit model

Background Since cartilage, unlike skin, does not contain vessels, it obtains nutrition by diffusion. This reduces graft viability, resulting in problems such as reductions in size, changes in shape, and resorption of the cartilage graft in the late post-graft period. This study aimed to investigate the effects of adipose-derived mesenchymal cells and conditioned medium (CM) on cartilage graft viability. Methods Dissections were performed 4 months after the injection of 0.5 mL of CM or 2×106 mesenchymal stem cells (MSCs) in 0.5 mL after grafting into a control group and two experimental groups (n=21 rabbits in total). Chondrocyte viability and type II collagen expression in the grafted areas were analyzed by hematoxylin-eosin staining and immunohistochemical methods, respectively. Results In the MSC and CM groups, chondrocyte proliferation at the graft tissue incision margin (MSC: P<0.01, CM: P<0.0001), chondrocyte proliferation at the auricular cartilage incision margin (MSC: P<0.05, CM: P<0.0001), integration of the graft with the surrounding cartilage (MSC: P<0.001, CM: P<0.0001) and type II collagen expression levels (MSC: P=0.001, CM: P=0.0002) significantly increased. Conclusions Xenogenic injection of MSCs and CM contributed to new cartilage production without any tumoral effects or immune reactions. In particular, the cell-free nature of CM strengthened its potential for safe use. Since injections of MSC and CM can preserve cartilage graft viability, interest in this technique is expected to increase as long-term results from clinical studies on the subject become available

Modelling of Eulerian incompressible fluid flows by using peridynamic differential operator

This study presents a novel method for modelling of Eulerian incompressible fluid flow by using peridynamic differential operator. The peridynamic differential operator is used to calculate partial derivatives in the Navier-Stokes equations. The pressure Poisson equation is used to obtain the pressure field whereas the velocity field is obtained by solving momentum equations. The numerical procedure to solve Navier-Stokes equations in peridynamics for the incompressible fluid is also provided. The capability of the proposed peridynamic incompressible fluid model is demonstrated by considering problems of two-dimensional cavitation, a flow inside an open channel, and a flow over a cylinder. Moreover, to demonstrate the capabilities of the proposed model, the problems of two-dimensional cavitation and a flow over a cylinder are investigated for different Reynolds numbers. The vortex shedding is also captured for the problem of a flow over a cylinder at Reynolds number of 푅푒 = 100. For verification purposes, the peridynamic results are compared with the results obtained by ANSYS Fluent, a commercial fluid dynamics software

Fatigue crack prediction in ceramic material and its porous media by using peridynamics

Peridynamics is a nonlocal reformulation of the classical continuum mechanics using integro-differential equations. Since the integro-differential equations used in peridynamics are valid in both continuous and discontinuous models, the theory is suitable for predicting progressive damages. In this study, fatigue crack growth in a ceramic material and its porous media is predicted by using the peridynamic model for fatigue cracking. First, the fatigue crack propagation in compact specimen of a non-porous ceramic material is considered. The predicted fatigue crack growth rate is compared with experimental results. Next, the fatigue crack growths in ceramic material with different porosity levels are investigated. The fatigue crack growth rate of porous materials is compared with the non-porous material to analyse the effects of porosity on fatigue crack growth. A linear relation between the relative change of fatigue crack growth rate, stress intensity factor range and porosity level is obtained by using linear regression analysis

Chronic hyperglycemia induces trans-differentiation of human pancreatic stellate cells and enhances the malignant molecular communication with human pancreatic cancer cells

BACKGROUND: Diabetes mellitus is linked to pancreatic cancer. We hypothesized a role for pancreatic stellate cells (PSC) in the hyperglycemia induced deterioration of pancreatic cancer and therefore studied two human cell lines (RLT-PSC, T3M4) in hyperglycemic environment. METHODOLOGY/PRINCIPAL FINDINGS: The effect of chronic hyperglycemia (CHG) on PSCs was studied using mRNA expression array with real-time PCR validation and bioinformatic pathway analysis, and confirmatory protein studies. The stress fiber formation (IC: αSMA) indicated that PSCs tend to transdifferentiate to a myofibroblast-like state after exposure to CHG. The phosphorylation of p38 and ERK1/2 was increased with a consecutive upregulation of CDC25, SP1, cFOS and p21, and with downregulation of PPARγ after PSCs were exposed to chronic hyperglycemia. CXCL12 levels increased significantly in PSC supernatant after CHG exposure independently from TGF-β1 treatment (3.09-fold with a 2.73-fold without TGF-β1, p<0.05). The upregualtion of the SP1 transcription factor in PSCs after CHG exposure may be implicated in the increased CXCL12 and IGFBP2 production. In cancer cells, hyperglycemia induced an increased expression of CXCR4, a CXCL12 receptor that was also induced by PSC's conditioned medium. The receptor-ligand interaction increased the phosphorylation of ERK1/2 and p38 resulting in activation of MAP kinase pathway, one of the most powerful stimuli for cell proliferation. Certainly, conditioned medium of PSC increased pancreatic cancer cell proliferation and this effect could be partially inhibited by a CXCR4 inhibitor. As the PSC conditioned medium (normal glucose concentration) increased the ERK1/2 and p38 phosphorylation, we concluded that PSCs produce other factor(s) that influence(s) pancreatic cancer behaviour. CONCLUSIONS: Hyperglycemia induces increased CXCL12 production by the PSCs, and its receptor, CXCR4 on cancer cells. The ligand-receptor interaction activates MAP kinase signaling that causes increased cancer cell proliferation and migration