Isolated linear blaschkoid psoriasis

Linear psoriasis (LPs) is considered a rare clinical presentation of psoriasis, which is characterized by linear erythematous and scaly lesions along the lines of Blaschko. We report the case of a 20‐year‐old man who presented with asymptomatic linear and S‐shaped erythematous, scaly plaques on right side of his trunk. The plaques were arranged along the lines of Blaschko with a sharp demarcation at the midline. Histological examination of a skin biopsy confirmed the diagnosis of psoriasis. Topical calcipotriol and betamethasone dipropionate ointments were prescribed for 2 months. A good clinical improvement was achieved, with reduction in lesion thickness and scaling. In patients with linear erythematous and scaly plaques along the lines of Blaschko, the diagnosis of LPs should be kept in mind, especially in patients with asymptomatic lesions of late onset.     

Association between miRNA-146a rs2910164 (G/C) polymorphism with the susceptibility to chronic HBV infection and spontaneous viral clearance in an Iranian population

Hepatitis B virus (HBV) infection is one of the clinical dilemmas in chronic liver diseases. MicroRNAs (miRNAs) are small noncoding RNA molecules that play an important role in the pathogenesis of liver diseases and single nucleotide polymorphisms (SNPs) in miRNA genes affect the clinical course of HBV infection. Previous studies have shown that miRNA-146a rs2910164 polymorphism can be associated with the pathogenesis of liver diseases such as hepatocellular carcinoma. The present study investigated the association between miRNA-146a rs2910164 polymorphism and susceptibility to HBV infection in an Iranian population. The study comprised 266 patients with chronic HBV infection, 172 patients with spontaneous viral clearance (SVC) after acute HBV infection, and 266 healthy control adjusted for sex and age. The genotyping of the miRNA-146a rs2910164 polymorphism was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Our data revealed that GG genotype and G allele of miRNA-146a rs2910164 SNP is dominated (P < 0.001) in patients with chronic HBV infection (Odds ratio [OR] = 3.92; 95% confidence interval [CI] = 2.1-7.32). miRNA-146a rs2910164 polymorphism showed a statistically significant association (P < 0.001) between CC genotype and allele C with SVC (OR = 2.92; 95% CI = 1.56-546). Our findings suggest miRNA-146a SNP (C/G) in our population may be associated with the susceptibility to HBV infection and CC genotype is associated with SVC. Also, the GG genotype and G allele at miRNA-146a rs2910164 is associated with chronic HBV infection in our population.     

Computational Flow Modeling of the Left Ventricle Based on In Vivo MRI Data: Initial Experience

A combined computational fluid dynamics (CFD) and magnetic resonance imaging (MRI) methodology has been developed to simulate blood flow in heart chambers, with specific application in the present study to the human left ventricle. The proposed framework employs MRI scans of a human heart to obtain geometric data, which are then used for the CFD simulations. These latter are accomplished by geometrical modeling of the ventricle using time-resolved anatomical slices of the ventricular geometry and imposition of inflow/outflow conditions at orifices notionally representing the mitral and aortic valves. The predicted flow structure evolution and physiologically relevant flow characteristics were examined and compared to existing information. The CFD model convincingly captures the three-dimensional contraction and expansion phases of endocardial motion in the left ventricle, allowing simulation of dominant flow features, such as the vortices and swirling structures. These results were qualitatively consistent with previous physiological and clinical experiments on in vivo ventricular chambers, but the accuracy of the simulated velocities was limited largely by the anatomical shortcomings in the valve region. The study also indicated areas in which the methodology requires improvement and extension. © 2001 Biomedical Engineering Society. PAC01: 8719Hh, 4711+j, 8761Lh, 8719Uv     

Low scolicidal effect of Ocimum bacilicum and Allium cepa on protoccoleces of hydatid cyst: an in vitro study

Hydatidosis in humans and animals is an economic and public health treat in many parts of the world, and surgery is still the main treatment for hydatid disease. One of the most important endpoints of hydatid cyst surgery is recurrence. The main cause of recurrence is dissemination of protoscolices during the surgical operation. Preoperative destruction of the cyst’s contents through instillation of a scolicidal agent into the hydatid cyst is the most commonly used approach to prevent this complication. Various scolicidal agents have been used for inactivation of the cyst content, but most are accompanied by adverse side effects. In the present study, the scolicidal effect of methanolic extract of Ocimum bacilicum and Allium cepa is investigated. Protoscoleces were aseptically collected from sheep livers containing hydatid cyst and were used in the experiments. O. bacilicum and A. cepa extracts were used in 2.5, 5, and 10 % concentration for 10, 20, 30, 40, 50, and 60 min. Viability of protoscoleces was confirmed by 0.1 % eosin staining. The scolicidal effect of O. bacilicum and A. cepa extracts was not satisfactory and a 10 % concentration of these extracts after 60 min of application, killed only 24.1 and 16.8 % of protoscolices, respectively. Result of this study showed that, as opposed to the fact that these extracts have a strong antibacterial effect, they have low scolicidal activity and cannot be used as scolicidal agent; on the contrary of in vitro inefficacy, the in vivo efficacy of these extracts and also their possible side effects remained to be examined.     

A New Template and Teleoperation System for Human‐Guided Spine Surgery

Fluoroscopy‐guided placement of pedicle screws is usually used to position pedicle screws, although it is highly risky due to lack of accuracy during operation and surgeon’s intensive labor requirement during surgery. In this study, a new method was introduced to consider the issues and we tried to reduce the risk of pedicle screw placement and drilling process. To put pedicle screws in the correct position and orientation, a specific drill guide is designed and fabricated by additive manufacturing technology. In addition, since the drilling process is remarkably important and it is usually dependent on surgeon skill, therefore a teleoperation system is proposed to perform this task. In order to let the surgeon to have better control on the patient, a control scheme including position and velocity signals along with surgeon force and reaction force of vertebra was proposed. This helped the surgeon for proper control on the patient during surgery. A force estimation algorithm was presented to eliminate measuring external force signal. Consequently, 10 vertebras were used to evaluate specific drill guide and teleoperation system simultaneously. Then, the computed tomography evaluation demonstrated that Kirschner wire trajectories followed the planned axes with an error between 1 and 2 mm in 20% of cases and less than 1 mm in 80% of cases. The results obtained by the teleoperation system showed that the surgeon, in the master side, has proper control over the patient body in the slave side because the slave robot followed the master position. Furthermore, the surgeon in the master side sensed the reaction force of vertebra in the slave side appropriately.