Down-regulating CD19 surface markers expression correlates with infectious bursal disease virus replication.

The infectious bursal disease virus (IBDV) causes an acute and highly contagious immunosuppressive response in young chickens by targeting B lymphocytes in immune organs. Changes in regulatory T-cell ratio and apoptosis have been demonstrated during IBDV infection in these cells. The possible change in CD19 expression as the precursor of B cells after IBDV replication was detected in this study. Raji cells were infected with an IBDV isolate at MOIs of 1.0 and 3.0. The viral kinetics were determined using the characteristic virus-induced CPE, cell viability, and infectious titer. Induction of apoptosis and also changes in the CD19 expression within the virus infection were assessed by flow cytometry. The Raji cells were found to be susceptible to IBDV infection by producing marked CPEs dependent on MOI. The infectivity titers were determined in intra- and extracellular samples at the defined hours. The kinetics of early IBDV replication in Raji cells were nearly identical for both MOIs, but a significant difference in the infectivity titer was observed at 48 hpi. The quick apoptotic events were observed to be significantly higher in MOI 3.0, which was correlated with the lower virus titer. A significant CD19 expression change in the IBDV-infected Raji cells was revealed. The results suggested that Raji cells mimic the IBDV replication in lymphoid organs and the virus replication is related to CD19 expression frequencies in the lymphoid cells.

Tween 80 improves the infectivity of BCL1 cell-adapted infectious bursal disease virus.

Non-ionic surfactants have the ability to alter the cell membrane's permeability for enhancing virus replication. The impact of non-ionic surfactant Tween 80 (TW80) on the infectivity of infectious bursal disease virus (IBDV) was studied in BCL1 cells. The toxicity of different concentrations of TW80 for BCL1 cells was determined for five-time passages. The confluent monolayer of BCL1 was infected by IBDV and subsequently passaged. The adaptation was confirmed by virus titration and RT-PCR assay. Replication kinetics of the cell-adapted IBDV was evaluated in pre-treatment and simultaneous treatment with TW80 at 0.01% concentration. The IBDV infectivity patterns were determined by virus titration, FRAP assay, and transmission electron microscopy. Sequence analysis, RNA secondary structure, and potential N-glycosylation site were conducted for IBDV VP2. Despite the similar cytopathic effects found in both TW80-treated cells and similar ROS levels, the IBDV titer was higher in TW80 pre-treated cells compared to the simultaneous treatment one. Such an increase in IBDV titer did not associate with changes in the VP2 sequence and RNA secondary structure. The possible antioxidant capacity of TW80 can attenuate the ROS damage and improve the cell viability, thereby improving IBDV infectivity.

Inertial microfluidics: Determining the effect of geometric key parameters on capture efficiency along with a feasibility evaluation for bone marrow cells sorting.

Despite great developments in inertial microfluidics, there is still a lack of knowledge to precisely define the particles' behavior in the microchannels. In the present study, as a prerequisite to experimental studies, numerical simulations have been used to study the capture efficiency of target particles in the contraction-expansion microchannel, aiming to provide an estimation of the conditions at which the channel performs best. Fluid analysis based on Navier-Stokes equations is conducted using the finite element method to determine the streamlines and vortices. The highest capture efficiency for 10, 15, and 19-micron particles occurs when the center of the vortex is approximately in the middle of the wide section (at the flow rate of 0.35 ml/min). In addition to investigating the effect of particle diameter and input flow rate, the effect of channel geometry parameters (channel height and initial length of the channel) on particle trapping has also been studied. Also, to consider great interest in separating different-sized bioparticles from a sample, a three-stage platform has been designed to separate four types of bone marrow cells and evaluate the possibility of using contraction-expansion channels in this application.

Event-Related Potentials of Bottom-Up and Top-Down Processing of Emotional Faces.

INTRODUCTION: Emotional stimulus is processed automatically in a bottom-up way or can be processed voluntarily in a top-down way. Imaging studies have indicated that bottom-up and top-down processing are mediated through different neural systems. However, temporal differentiation of top-down versus bottom-up processing of facial emotional expressions has remained to be clarified. The present study aimed to explore the time course of these processes as indexed by the emotion-specific P100 and late positive potential (LPP) event-related potential (ERP) components in a group of healthy women. METHODS: Fourteen female students of Alzahra University, Tehran, Iran aged 18-30 years, voluntarily participated in the study. The subjects completed 2 overt and covert emotional tasks during ERP acquisition. RESULTS: The results indicated that fearful expressions significantly produced greater P100 amplitude compared to other expressions. Moreover, the P100 findings showed an interaction between emotion and processing conditions. Further analysis indicated that within the overt condition, fearful expressions elicited more P100 amplitude compared to other emotional expressions. Also, overt conditions created significantly more LPP latencies and amplitudes compared to covert conditions. CONCLUSION: Based on the results, early perceptual processing of fearful face expressions is enhanced in top-down way compared to bottom-up way. It also suggests that P100 may reflect an attentional bias toward fearful emotions. However, no such differentiation was observed within later processing stages of face expressions, as indexed by the ERP LPP component, in a top-down versus bottom-up way. Overall, this study provides a basis for further exploring of bottom-up and top-down processes underlying emotion and may be typically helpful for investigating the temporal characteristics associated with impaired emotional processing in psychiatric disorders.

Association involving serotonin transporter gene linked polymorphic region and bipolar disorder type 1 in Iranian population.

INTRODUCTION: Serotonin transporter gene linked polymorphic region, also called 5HTTLPR, is a candidate in the genetics of bipolar disorder; however, the results of previous association studies are inconsistent. Several explanations have been proposed for that inconsistency; among them are the existing differences both in the genetic basis of bipolar disorder subtypes and the genetic backgrounds of the studied populations. We aimed to investigate the association of 5HTTLPR with bipolar disorder type I (BP-1) in Iranian population. METHODS: In this case-control study, 146 patients with BP-1 and 165 controls were recruited. The patients were selected through the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition. It was required that the patients do not have any present history of general medical conditions, substance abuse, and concurrent major psychiatric disorders. The polymorphism was evaluated by blood sampling and subsequent DNA extraction, polymerase chain reaction, and agarose gel electrophoresis. Chi-square test was used for analyzing allelic and genotype frequencies and two-tailed P values were obtained. RESULTS: The S allele was significantly more frequent in the BP-1 patients compared with the controls (P = 0.02, S allele odds ratio = 1.5, confidence interval 95% = 1.06-2.11). DISCUSSION: Our statistically significant results suggest that the role of 5HTTLPR in the pathogenesis of BP-1 needs to be clarified by further scrutiny in Iranian population and other populations of Near East.

Spectrophotometric determination of sulfide based on peroxidase inhibition by detection of purpurogallin formation.

This paper presents a new method for spectrophotometirc detection of sulfide applying fungal peroxidase immobilized on sodium alginate. The sensing scheme was based on decrease of the absorbance of the orange compound, purpurogallin produced from pyrogallol and H2O2 as substrates, due to the inhibition of peroxidase by sulfide. Absorbance of purpurogallin was detected at 420nm by using a spectrophotometer. The proposed method could successfully detect the sulfide in the concentration range of 0.6-7.0µM with a detection limit of 0.4µM. The kinetic parameters of Michaelis-Menten with and without sulfide were also calculated. Possible inhibition mechanism of peroxidase by sulfide was deduced according to the variation of parameters and uncompetitive mechanism was observed with respect to hydrogen peroxide. The current method provides an easy to use method for sulfide detection in water samples.

Amperometric sulfide detection using Coprinus cinereus peroxidase immobilized on screen printed electrode in an enzyme inhibition based biosensor.

In the present work, an amperometric inhibition biosensor for the determination of sulfide has been fabricated by immobilizing Coprinus cinereus peroxidase (CIP) on the surface of screen printed electrode (SPE). Chitosan/acrylamide was applied for immobilization of peroxidase on the working electrode. The amperometric measurement was performed at an applied potential of -150 mV versus Ag/AgCl with a scan rate of 100 mV in the presence of hydroquinone as electron mediator and 0.1M phosphate buffer solution of pH 6.5. The variables influencing the performance of sensor including the amount of substrate, mediator concentration and electrolyte pH were optimized. The determination of sulfide can be achieved in a linear range of 1.09-16.3 µM with a detection limit of 0.3 µM. Developed sensor showed quicker response to sulfide compared to the previous developed sulfide biosensors. Common anions and cations in environmental water did not interfere with sulfide detection by the developed biosensor. Cyanide interference on the enzyme inhibition caused 43.25% error in the calibration assay which is less than the amounts reported by previous studies. Because of high sensitivity and the low-cost of SPE, this inhibition biosensor can be successfully used for analysis of environmental water samples.

Association of P1635 and P1655 polymorphisms in dysbindin (DTNBP1) gene with schizophrenia.

OBJECTIVES: Schizophrenia (SCZ) is a severe psychiatric disorder with a lifetime prevalence of approximately 1% in most of the populations studied. SCZ is multifactorial with the contribution of multiple susceptibility genes that could act in conjunction with epigenetic processes and environmental factors. There is some evidence supporting the association between genetic variants in dysbindin (DTNBP1) gene and SCZ in populations. In this study, we investigated the association between polymorphisms P1635 and P1655 in dysbindin gene with SCZ. METHODS: Totally, 115 unrelated patients with SCZ and 117 unrelated healthy volunteers were studied. Genomic DNA was extracted from blood. Genotyping was done with the PCR-RFLP method. The allele and genotype associations were analysed with X 2 test. The Benjamini-Hochberg procedure was used to correct p values for multiple comparisons. RESULTS: The results showed no significant difference between patients and controls in allelic frequencies or genotypic distributions of SNP P1635 (p = 0.809), but a significant difference between the case and control groups for SNP P1655 (p = 0.009) was found. We could also find a significant positive association between A-C haplotype and SCZ (OR = 1.7, 95% CI 1.18-2.42; p = 0.004, p c = 0.02) and a protective effect for A-G haplotype (p = 0.003, OR = 0.57, 95% CI 1.18-2.42; p = 0.003, p c = 0.02). CONCLUSION: This study may provide further support for the association between SNP polymorphisms in DTNBP1 and SCZ in the Iranian population. Studies with more markers and subjects for various populations will be necessary to understand the genetic contribution of the gene to the development of SCZ.

Efficacy and safety of naloxone in the management of postseizure complaints of tramadol intoxicated patients: a self-controlled study.

BACKGROUND AND AIMS: Tramadol has become a major cause of drug-induced seizure recently. Naloxone is reported to attenuate the seizurogenic activity of tramadol. Thus, the authors aimed to study the efficacy and safety of naloxone in the management of postseizure complaints. METHODS: This self-controlled study was conducted from August 2006 to August 2008. 59 tramadol intoxicated patients who did have postseizure complaints entered the study. After initial resuscitation and work-up, they received intravenous naloxone 0.05 mg every 3-5 min, and the presence of symptoms, presence of abnormal waves in cerebral state monitor (CSM), cerebral state index (CSI) and optical density (OD) were assessed. RESULTS: 47 participants completed the study, of whom 43 (91%) had symptom resolution after the intervention, and the presence of symptoms was significantly different before and after the intervention (p<0.001). 47 patients had abnormal waves in the CSM before the intervention, while 15 had abnormal waves in the CSM after intervention (p<0.001). The baseline mean of CSI was 81 (SD: 5.17), which was significantly increased to 92 (SD: 2.35) after naloxone injection (p<0.001). The baseline mean of OD was 7.1 (SD: 0.23), which was significantly increased to 7.7 (SD: 0.29) after naloxone injection (p<0.001). CONCLUSION: Naloxone can be considered in the management of postseizure complaints of tramadol toxicity, but further rigorous studies are needed to provide sufficient evidence to support its routine use.