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In the present study, the deposition of silicon nitride (Si3N4) coating on Inconel 738 through plasma spray has been investigated. For producing the Si3N4 coating, different times (6, 8 and 10 s), different distances of the plasma spray torch from the substrate (30, 35 and 40 mm) and different currents for plasma spraying (3000, 3250 and 3500 A) were employed. For the characterisation of the coatings, SEM (thickness), XRD, micro-hardness and adhesion of the samples were measured. The coatings' surface morphology was investigated through SEM. Based on the experimental results, by using a spraying time of 10 s, a distance of the torch of 40 mm and a current of 3500 A, high microhardness and adhesion of the coatings are obtained. On the other hand, the thickness of the coating increased by reducing the distance and increasing spray time and current. [ABSTRACT FROM AUTHOR]

Background: Cytomegalovirus (CMV) infection is the most common complications following kidney transplantation. Natural killer (NK) cells demonstrated critical anti-viral role in controlling and elimination of CMV after transplantation. Interleukin-15 (IL-15) is a pleiotropic cytokine that promotes the activity of NK cells and strengthens the acquired immune system. Also, IP10 (CXCL10) is a chemotactic factor which regulates NK cell recruitment and antiviral immune response. We aimed to determine the correlation between the serum levels of IL-15 and IP-10 cytokines with CMV infection, CMV viral load, and cyclosporine as a major immunosuppressive treatment after transplantation. Methods: Fifty-eight kidney transplant recipient patients without evidence of CMV virus disease before transplantation surgery were included in the study. From the day of transplant surgery, the patients were evaluated based on the presence of CMV Ag pp65, CMV viral load, serum levels of IL-15 & IP-10, Cyclosporine levels (C0 & C2), Glomerular Filtration Rate (GFR), and hematological & biochemical Index, up to 75 days. Results: Comparison analysis of serum levels of IL-15 and IP-10 showed no significant association with CMV infection in kidney transplant recipients. In addition, CMV viral load and cyclosporine levels at C0 and C2 did not affect patients' IL-15 and IP-10 levels. Conclusions: The levels of IP-10 and IL-15 cytokines are not affected with CMV infection, even if a viral infection occurs in the early days after transplantation or long afterwards. In addition, taking the different levels of cyclosporine did not affect the cytokines levels. Other mechanisms may play a role in maintaining the levels of these cytokines. [ABSTRACT FROM AUTHOR]

Diabetic foot ulcer is one of the most common causes of amputation and imposes high social costs. The present study was conducted to evaluate the effect of oral arnebia euchroma extract on wounds in diabetic rats and was compared with oral and topical forms of ANGIPARS.Thirty diabetic male Wistar rats were categorized into different groups with similar wounds, and were treated with oral and topical forms of arnebia euchroma extract and ANGIPARS ointment and capsules, and were compared with each other and the control group. The clinical and statistical results indicate the superior effect of oral and topical forms of arnebia euchroma extract in comparison with oral and topical forms of ANGIPARS.The epithelial thickness(F (4.25) = 4189.10, p<0.01) and complete healing time(F (4.25) = 18.01, p<0.01), were respectively calculated. It is recommended that a human study be conducted to determine the level of blood glucose and its effect on TNFa and myeloperoxidase as the factors affecting tissue repair. [ABSTRACT FROM AUTHOR]

Summary: Recurrent vulvovaginal candidiasis (RVVC) is a common opportunistic, mucosal fungal infection, predominantly caused by the fungus Candida albicans. Mannose‐binding lectin (MBL) is an acute‐phase protein that plays a key role in the innate immunity defence against infectious disease. This study was conducted to evaluate the relationship between the MBL serum level and the relative expression of MBLmRNA in RVVC using real‐time PCR for the first time. The case‐control study included 40 female participants suffering from RVVC and 40 healthy individuals. The MBL serum level was measured using a commercial ELISA kit. The relative mRNA expression of the MBL gene was quantified using real‐time PCR. Data analysis was carried out by spss software. The MBL concentration was significantly higher in the participants suffering from RVVC compared to the control group (0.330 ng/mL vs 0.253 ng/mL). The prognostic value (P < .001) for RVVC diagnosis has been calculated. Quantitative RT‐PCR results from 35 samples showed a low to significant values for mRNA levels corresponding to MBL gene expression (1‐352 folds) (P < .001). The results of this study suggest that MBL plays a main role in the innate immunity and it is also affected by environmental factors and other genetic variations. Therefore, the MBL gene expression profile does not reflect precise phenotypic levels in the serum. [ABSTRACT FROM AUTHOR]

Abstract This cohort intends to determine the sequential dynamic changes in Toll-like receptor (TLR)-4, TLR-2, and myeloid differentiation primary response gene 88 (MYD88) mRNA expressions in PBMCs and biopsy samples from kidney allograft recipients in relation to graft function. This study enrolled 52 renal transplant patients, 27 with well functioning graft (WFG) and 25 graft dysfunction (GD). Peripheral blood samples pre- and post-transplantation (days 2, 90 and 180) were collected to analyze mRNA expression levels of TLR-2, TLR-4, and MYD88 genes in relation to allograft function during one-year follow up. The mean dynamic changes of post-transplant TLR-2, TLR-4, and MYD88 mRNA expressions were significantly higher in GD compared to WFG patients (P =.001). ROC curve analysis based on glomerular filtration rate (GFR) index showed the area under curve (AUC) values for the genes: TLR-2(0.89;P <.001), TLR-4(0.86;P <.001), and MYD88(0.75;P =.003) in the third month post-transplantation for GD diagnosis. The calculated AUCs for the expressions of genes in allograft biopsies were 0.94(TLR-2), 0.95(TLR-4), and 0.98(MYD88) in the sixth month post-transplant based on pathology report (P <.001). Our results indicate that sequential monitoring of the expression patterns of TLR-2, TLR-4, and MYD88 in PBMCs and biopsy samples could be considered as predictive biomarkers for early and late kidney allograft function. Highlights • TLR-4, TLR-2 and MYD88 involved in alloimmune responses leading to allograft rejection. • Higher expression of TLR-2,4 & MYD88 post-transplant were observed in GD compared to WGF patients. • Higher expressions of all 3 genes were observed in patients with abnormal biopsy compared to NPR. • Monitoring of the expression patterns of TLR-2, TLR-4, and MYD88 suggested as predictive biomarkers for early and late kidney GD. [ABSTRACT FROM AUTHOR]

In the present work, an attempt is made to study the predominant factors of ball burnishing namely, burnishing speed, burnishing feed, burnishing force, and pass number on the surface roughness, surface hardness, and out-of-roundness error of hard-turned AISI 4340 rods. Response surface methodology was used to correlate the empirical relationship between the process factors and responses. Also, the minimum surface roughness, out-of-roundness error, as well as the maximum hardness were taken into consideration for finding the optimal parameter setting. Analysis of variances was also performed to check the adequacy of the developed models. Results indicated that the most influential parameters for the surface roughness and roundness error is the burnishing feed. Also, for surface hardness, it was found that the pass number had the greatest influence. It was further seen that a burnishing speed of 150 r/min, burnishing feed of 0.16 mm/rev, burnishing force of 24.5 N, and pass number 4 yields the desirable burnishing quality characteristics. The obtained results were then validated through performing morphological study and microstructural observation of the burnished surface. [ABSTRACT FROM AUTHOR]

Background: Diagnosis of allograft dysfunction by noninvasive biomarker tests is preferable to invasive allograft biopsies and has been extensively considered in recent years. This study aims to evaluate blood and urinary forkhead box P3 (FOXP3) messenger RNA (mRNA) expression in renal transplant recipients in an attempt to determine whether differential diagnosis of graft dysfunction is feasible using mRNA profiles. Methods: We analyzed FOXP3 mRNA expression in paired urinary and peripheral blood mononuclear cell (PBMC) samples. A total of 91 kidney transplant recipients enrolled in this study that were classified into 3 groups: biopsy-proven acute rejection (AR; n = 27), chronic allograft nephropathy (n = 19), and well-functioning graft (n = 45). The FOXP3 mRNA expression was quantified by TaqMan probe real-time polymerase chain reaction. Results: Acute rejection patients had a higher expression level of transcription factor FOXP3 compared to the chronic nephropathy and control groups. Analysis of receiver operating characteristic curves showed that rejection could be diagnosed with 100% sensitivity and 96% specificity in urine, and 92% sensitivity and 86% specificity in PBMC samples using the optimal FOXP3 mRNA cutoff value. We subdivided the AR group into progressive and nonprogressive patients, which showed a significant difference in FOXP3 mRNA expression. This result confirmed the role of FOXP3 as a diagnostic marker in predicting transplantation outcomes. Conclusion: Our results suggested that elevated expression of FOXP3 in blood and urine samples from kidney transplant recipients could be a useful noninvasive biomarker to diagnose graft dysfunction. [ABSTRACT FROM AUTHOR]

In present study, an attempt based on a hybrid approach was made to find optimal tube drawing parameters combination (i.e., die semi-angle, friction coefficient, tube entrance velocity, deformation length, and primary tube diameter) achieving minimum forming force, minimum dimensional error along with maximum thickness in longitudinal and circumferential directions. In order to form a design matrix, Taguchi L27 design was used and required data were derived from finite element model of the process. Adaptive neuro-fuzzy inference system (ANFIS) was then used to correlate process inputs to and responses aforementioned response outputs. Prediction accuracy of created ANFIS models was further checked by FE simulation and experimental testing data. Finally, the models were integrated to form objective function that was optimized by teaching–learning-based optimization (TLBO) algorithm. To check the adequacy of optimization, a finite element run and an experiment were carried out by obtained optimal parameter setting and the results were compared. The findings indicated that that the proposed methodology, that is, FEA-ANFIS-TLBO has superiority in identifying the optimal results. [ABSTRACT FROM AUTHOR]

Metallic bipolar plates are the most important part of proton exchange membrane fuel cell (PEMFC). In order to manufacturing of these plates, various method such as Hydroforming, electromagnet forming and stamping have been used. In this study rubber pad forming process was selected in order to forming metallic bipolar plates with stainless steel 316. At first effect of punch load, thickness and hardness of rubber on channel depth (before fracture) were investigated in order to determinate the maximum channel depth before fracture. After that, a novel method was developed by machining the rubber pad in order to prevent from fracture and increase in channel depth. According to the result, increase in hardness of rubber lead to decrease in channel depth and increase in applied force and thickness of rubber lead to increase in channel depth. Maximum filling percentage (before fracture) in rubber pad forming process was 76% achieved by Shore A 40 rubber pad with thickness of 30 mm and maximum thinning percentage before fracture is about 30%. Using new method was successful to prevent from fracture and formability has been increased by machining the rubber pad. As a result, the filling percentage for bipolar plate increased to 88%. [ABSTRACT FROM AUTHOR]

The aim of this article is the investigation of the effects of tool tilt angle on the friction stir welding of aluminium to the steel butt joint. For this purpose, 1°, 2° and 3° tilt angles are selected to friction stir welding of AA1100 to A441 AISI, while the other process parameters (i.e. tool rotational speed, travelling speed, tool offset and plunge depth) kept constant. The results showed that with increasing tool tilt angle, the interaction between two metals and axial force increased. The increasing tool tilt angle caused more surfaces to mingle, internal mixing and frictional heat generation. The results of the microstructure of joints revealed that the AA1100 microstructure is more thermo-mechanically affected than A441 AISI. The AA1100 average grain sizes at stir zone were 1.2, 1.6 and 2 µm and at A441 AISI were 6, 7 and 9 µm at 1°, 2° and 3° tilt angles, respectively. The maximum tensile strength of joints was 75% of the aluminium base metal, which was produced at 2° tilt angle. The higher heat generation and axial force at upper tilt angle cause separation of the steel fragments on the aluminium matrix and formation of Al-Fe intermetallic compound. These phenomena lead to increase in the micro-hardness of the joint at the upper tool tilt angle. [ABSTRACT FROM AUTHOR]

T cell immunoglobulin and mucin domain 3 (TIM-3), as a co-inhibitory receptor expressed on Th1, Th17, CD8T, FoxP3 + Treg and innate immune cells, plays an important role in suppression of T cell-mediated immune responses, tolerance induction and T cell exhaustion. In this study, we evaluated sequential alterations of TIM-3 mRNA expression level in blood and urine samples of renal transplant recipients to predict approaching clinical episodes. A total of 52 adult renal transplant recipients (31 male and 21 female) were enrolled in this study. All the patients received kidney transplant from living unrelated donors. TIM-3 mRNA expression in peripheral blood mononuclear cells (PBMCs) and urinary cells were quantified using Real Time TaqMan polymerase chain reaction (PCR) at 4 different time points (pre-transplantation, 2, 90 and 180 days post-transplantation). TIM-3 mRNA expression level on days 2, 90 and 180 after transplantation was significantly higher in blood and urine samples of patients with graft dysfunction (GD) compared with patients with well-functioning graft (WFG). Our results also showed a high correlation between blood and urinary level of TIM-3 mRNA expression. The data from Receiver Operating Characteristic (ROC) Curve Analysis showed that blood and urinary TIM-3 mRNA expression level at month 3 and 6 could discriminate graft dysfunction (GD) from well-functioning graft (WFG) with high specificity and sensitivity. Our data suggested that serial monitoring of TIM-3 mRNA level in the blood and urine samples of renal transplant recipients could be a useful non-invasive biomarker for prediction and diagnosis of allograft dysfunction. [ABSTRACT FROM AUTHOR]

Background T cell immunoglobulin and mucin domain 3 (TIM-3) is involved in alloimmune and autoimmune responses, as well as tolerance induction in kidney transplantation. Kidney injury molecule-1 (KIM-1) is highly expressed in epithelial cells of the injured proximal tubule. In this study, we have investigated both urinary and blood TIM-3 mRNA expressions, urinary KIM-1 mRNA expression, and urinary and serum KIM-1 proteins in renal allograft recipients diagnosed with acute allograft rejection (AR) and chronic allograft dysfunction (CAD), as well as those with well-functioning transplants (WFG). Methods We divided 85 patients into the following groups: AR (n = 24), CAD (n = 19), and WFG (n = 42). TIM-3 and KIM-1 mRNA expressions were quantified using real-time reverse-transcription TaqMan probe polymerase chain reaction (RT-PCR). An ELISA test was used to measure the amount of KIM-1 protein in serum and urine samples. Results AR and CAD patients had significantly greater urinary and blood TIM-3 mRNA expressions, urinary KIM-1 mRNA expression, and urinary and serum KIM-1 proteins compared to WFG patients. Receiver operating characteristic (ROC) analysis showed that these molecules discriminated Allograft rejections from WFG. Conclusion Quantification of TIM-3 and KIM-1 mRNA expressions, along with KIM-1 protein measurements in urine and blood could be employed as promising tools for noninvasive diagnosis of allograft dysfunction. [ABSTRACT FROM AUTHOR]

Background Leukocyte infiltration into the graft has pivotal effects on kidney transplantation outcome. The present study sought to determine whether the expression of sequential chemokine receptors on CD4 + and CD8 + T cells in human renal allograft can predict clinical episodes. Methods Blood samples from 52 consecutive renal transplant patients were evaluated at the time of transplantation and at three times (2, 90 and 180 days) after transplantation to analyze the expression of CCR1 and CXCR3 on CD4 + and CD8 + T cells by flowcytometry. A total of 30 biopsies, including protocol biopsy (n = 24) and cause biopsy (n = 6), were investigated according to the Banff criteria. Results The mean percentage of CD4 + and CD8 + T cells expressing CCR1 was significantly increased in patients with allograft dysfunction (n = 25) (p = 0.006, p = 0.004). The mean fluorescence intensity of CXCR3 on CD4 + and CD8 + T cells were found to be significantly higher in graft dysfunction than that in well-functioning grafts. (p < 0.001, p = 0.007). Receiver Operating Characteristic (ROC) Curve Analysis showed that the calculated AUC was 0.86 at the third month for CD4 + CCR1 + and CD8 + CCR1 + (p < 0.001). Multiple logistic regression analysis showed that an increase in CD4 + expressing CXCR3 leads to a lower risk of graft dysfunction (OR = 0.37), while an increase in CD8 + expressing CCR1 results in a higher risk of graft dysfunction (OR = 3.66). Conclusion During renal transplantation, CD4 + and CD8 + T cells expressing CCR1 were increased in patients who developed graft dysfunction. These findings may prospectively predict allograft dysfunction, and help elucidate the underlying pathogenic mechanisms. [ABSTRACT FROM AUTHOR]

Background MicroRNAs (miRNAs) regulate most of encoding genes and protein. In this study, we aimed to investigate the expression levels of miR-142-5p, miR-142-3p, miR-155 and miR-223 in paired biopsy and peripheral blood mononuclear cell (PBMC) samples of renal allograft recipients with acute T-cell mediated rejection (ATCMR), compared with normal allografts (NA). Methods In this study, the expression levels of individual miRNAs were determined in biopsy and PBMC samples of 17 recipients with ATCMR and 18 recipients with NA. Results Our results showed that the intragraft expression levels of all studied miRNAs were significantly higher in ATCMR than NA. However, regarding the PBMC samples, miR-142-3p and miR-223 were significantly increased in ATCMR than NA. Receiver operating characteristic (ROC) analysis showed that miR-142-5p, miR-142-3p, miR-155 and miR-223 in biopsy samples and miR-142-3p and miR-223 in PBMC samples could discriminate ATCMR from NA recipients. Conclusion It has been reported that high intragraft expressions of miRNAs have a profound role in the pathogenesis of ATCMR process. Our results showed that high expression of all the studied miRNAs in biopsies and miR-142-3p and miR-223 in PBMC samples could be used as suggestive diagnostic tools to discriminate ATCMR patients from NA. [ABSTRACT FROM AUTHOR]

Introduction: Migraine can cause headache in different communities so that 12-15% are suffering worldwide. Recently the relationship between infectious diseases such as Helicobacter pylori infection and migraine headache has been the focus of many studies. The current study was designed to evaluate IgG and IgM antibodies to H. pylori in patients suffering from migraine headaches., Material and Methods: Patients who had diagnostic criteria for migraine were chosen as cases compared to some healthy individuals as the control group amongst which immunoglobulin G (IgG), immunoglobulin M (IgM), age, job, gastro-intestinal (GI) disorders, history of migraine, special meals, medications, sleeping disorders, stress, environmental factors etc were analysed., Results: The prevalence of disease was 38.6%. Household women had the highest prevalence (40%). Among them menstruation was related to high prevalence of migraine. 75.6% of patients had gastrointestinal disorders of which the gastric reflux was the most important sign (47.1%). The mean optical density (OD) value of IgG and IgM antibody to H. pylori was 60.08 ±7.7 and 32.1 ±8.7 for the case group, 21.82 ±6.2 and 17.6 ±9.4 for the control group, respectively., Conclusions: There was a significant difference in mean OD value of both antibodies to H. pylori amongst the case and control groups. As a result, active H. pylori infection is strongly related to the outbreak and severity of migraine headaches, and H. pylori treatment reduces migraine headaches significantly. Hopefully, the definite treatment and eradication of this infection can cure or reduce the severity and course of migraine headaches significantly if not totally.