Bromelain-loaded nanocomposites decrease inflammatory and cytotoxicity effects of gliadin on Caco-2 cells and peripheral blood mononuclear cells of celiac patients.

Enzyme therapy can be an appropriate treatment option for celiac disease (CeD). Here, we developed Bromelain-Loaded Nanocomposites (BLNCs) to improve the stability and retention of bromelain enzyme activity. After the characterization of BLNCs, the cytotoxicity of BLNCs was determined on the Caco-2 cell line. The effect of BLNCs on gliadin degradation and the production of pro-inflammatory cytokines and anti-inflammatory molecules in peripheral blood mononuclear cells (PBMCs) obtained from celiac patients were assessed. Furthermore, the expression of CXCR3 and CCR5 genes was measured in CaCo-2 cells treated with gliadin, gliadin-digested with BLNCs, and bromelain. Our study demonstrated that the Bromelain entrapment efficiency in these nanoparticles was acceptable, and BLNCs have no toxic effect on cells. SDS-PAGE confirmed the digestion effect of bromelain released from nanocomposites. When Caco-2 cells were treated with gliadin digested by free bromelain and BLNCs, the expression of CXCR3 and CCR5 genes was significantly decreased. PBMCs of celiac patients treated with Bromelain and BLNCs decreased inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ) production compared to untreated PBMCs. This treatment also increased IL-10 and CTLA-4 in PBMCs of CeD patients. According to the promising results of this study, we can hope for the therapeutic potential of BLNCs for CeD.

Dependence of trunk muscle size and position on age, height, and weight in a multi-ethnic cohort of middle-aged and older men and women.

Trunk muscle size and location relative to the spine are key factors affecting their capacity to assist in trunk movement, strength, and function. There remains limited information on how age, weight and height affect these measurements across multiple spinal levels, and prior studies had limited samples in terms of size and ethnicity. In this study, we measured trunk muscles in coronal plane slices at T4 - L4 of CT scans acquired in 507 participants, aged 40-90 years, from the community-based Framingham Heart Study. Mixed-effects linear regressions, stratified by sex, determined the contributions of age, height and weight, to muscle cross-sectional area (CSA), the distance from the vertebral body centroid (CD), and the in-plane angle of the line between the vertebral body and the muscle centroids (CA). Muscle CSA decreased with higher age by an average of -0.8% per year, but weight (average 0.8% per kg) and height (average -0.05% per cm) had mixed results, with both positive and negative effects depending on muscle group and level. Muscle CD increased with weight by an average of 0.3% per kg, but had mixed effects for age (average 0.8% per year) and height (average 0.1% per cm). Muscle CA had mixed associations with age (average 0.05% per year), weight (average 0.01% per kg) and height (average -0.05% per cm). A prediction program created with these results provides a simple approach for estimating probable values for trunk muscle size and position in the absence of medical imaging.

In vivo evaluation of bone regeneration using ZIF8-modified polypropylene membrane in rat calvarium defects.

AIM: The profound potential of zeolitic imidazolate framework 8 (ZIF8) thin film for inducing osteogenesis has been previously established under in vitro conditions. As the next step towards the clinical application of ZIF8-modified substrates in periodontology, this in vivo study aimed to evaluate the ability of the ZIF8 crystalline layer to induce bone regeneration in an animal model defect. MATERIALS AND METHODS: Following the mechanical characterization of the membranes and analysing the in vitro degradation of the ZIF8 layer, in vivo bone regeneration was evaluated in a critical-sized (5-mm) rat calvarial bone defect model. For each animal, one defect was randomly covered with either a polypropylene (PP) or a ZIF8-modified membrane (n = 7 per group), while the other defect was left untreated as a control. Eight weeks post surgery, bone formation was assessed by microcomputed tomography scanning, haematoxylin and eosin staining and immunohistochemical analysis. RESULTS: The ZIF8-modified membrane outperformed the PP membrane in terms of mechanical properties and revealed a trace Zn+2 release. Results of in vivo evaluation verified the superior barrier function of the ZIF8-coated membrane compared with pristine PP membrane. Compared with the limited marginal bone formation in the control and PP groups, the defect area was almost filled with mature bone in the ZIF8-coated membrane group. CONCLUSIONS: Our results support the effectiveness of the ZIF8-coated membrane as a promising material for improving clinical outcomes of guided bone regeneration procedures, without using biological components.

Determination of antifungal activity and action mechanism of the modified Aurein 1.2 peptide derivatives.

BACKGROUND: With the emergence of drug-resistant fungi and the increased population prone to fungal infections, more effective antifungal drugs are needed. Aurein 1.2 is a potent antimicrobial peptide. Here, we designed a novel derivative of Aurein 1.2, called Aurein N3, which is a modified form of Aurein N2 (another Aurein 1.2 derivative), in which Lys 8 residue was replaced with Leu 13, and was also modified by creating two other mutations. METHODS: Aurein N3 was designed using several algorithms and docking studies. All peptides were synthesized and some of their bio-activity indices such as antifungal properties on 11 fungi, cytotoxicity, hemolysis, and time of the killing were investigated. Electron microscopy, lived/dead staining, and ergosterol binding assay were performed to study their mechanism of action. RESULTS: In comparison to Aurein 1.2 and N2, the docking studies showed that Aurein N3 has reduced binding energy toward ergosterol. The antifungal assessments showed that both Aurein N2 and N3 had strong activity against many fungi. Aurein N3 had lower cytotoxicity and higher binding capability to ergosterol. The hemolytic activity of Aurein N2 and N3 was less than parental Aurein 1.2. All peptides were able to attack the cell wall/membrane and enter the fungi cells. CONCLUSION: Here we introduced a novel derivative of Aurein 1.2 which has lower cytotoxicity, higher ergosterol-binding capability, and comparable antifungal activity compared to the original peptides. It can bind to ergosterol and can also attack the cell wall/membrane of fungi, although more studies are required to find its accurate mechanism of action.

Walking Biomechanics and Spine Loading in Patients With Symptomatic Lumbar Spinal Stenosis.

Symptomatic lumbar spinal stenosis is a leading cause of pain and mobility limitation in older adults. It is clinically believed that patients with lumbar spinal stenosis adopt a flexed trunk posture or bend forward and alter their gait pattern to improve tolerance for walking. However, a biomechanical assessment of spine posture and motion during walking is broadly lacking in these patients. The purpose of this study was to evaluate lumbar spine and pelvic sagittal angles and lumbar spine compressive loads in standing and walking and to determine the effect of pain and neurogenic claudication symptoms in patients with symptomatic lumbar spinal stenosis. Seven participants with symptomatic lumbar spinal stenosis, aged 44-82, underwent a 3D opto-electronic motion analysis during standing and walking trials in asymptomatic and symptomatic states. Passive reflective marker clusters (four markers each) were attached to participants at T1, L1, and S2 levels of the spine, with additional reflective markers at other spinal levels, as well as the head, pelvis, and extremities. Whole-body motion data was collected during standing and walking trials in asymptomatic and symptomatic states. The results showed that the spine was slightly flexed during walking, but this was not affected by symptoms. Pelvic tilt was not different when symptoms were present, but suggests a possible effect of more forward tilt in both standing (p = 0.052) and walking (p = 0.075). Lumbar spine loading during symptomatic walking was increased by an average of 7% over asymptomatic walking (p = 0.001). Our results did not show increased spine flexion (adopting a trunk-flexed posture) and only indicate a trend for a small forward shift of the pelvis during both symptomatic walking and standing. This suggests that provocation of symptoms in these patients does not markedly affect their normal gait kinematics. The finding of increased spine loading with provocation of symptoms supports our hypothesis that spine loading plays a role in limiting walking function in patients with lumbar spinal stenosis, but additional work is needed to understand the biomechanical cause of this increase.

The Influence of Kinematic Constraints on Model Performance During Inverse Kinematics Analysis of the Thoracolumbar Spine.

Motion analysis is increasingly applied to spine musculoskeletal models using kinematic constraints to estimate individual intervertebral joint movements, which cannot be directly measured from the skin surface markers. Traditionally, kinematic constraints have allowed a single spinal degree of freedom (DOF) in each direction, and there has been little examination of how different kinematic constraints affect evaluations of spine motion. Thus, the objective of this study was to evaluate the performance of different kinematic constraints for inverse kinematics analysis. We collected motion analysis marker data in seven healthy participants (4F, 3M, aged 27-67) during flexion-extension, lateral bending, and axial rotation tasks. Inverse kinematics analyses were performed on subject-specific models with 17 thoracolumbar joints allowing 51 rotational DOF (51DOF) and corresponding models including seven sets of kinematic constraints that limited spine motion from 3 to 9DOF. Outcomes included: (1) root mean square (RMS) error of spine markers (measured vs. model); (2) lag-one autocorrelation coefficients to assess smoothness of angular motions; (3) maximum range of motion (ROM) of intervertebral joints in three directions of motion (FE, LB, AR) to assess whether they are physiologically reasonable; and (4) segmental spine angles in static ROM trials. We found that RMS error of spine markers was higher with constraints than without (p < 0.0001) but did not notably improve kinematic constraints above 6DOF. Compared to segmental angles calculated directly from spine markers, models with kinematic constraints had moderate to good intraclass correlation coefficients (ICCs) for flexion-extension and lateral bending, though weak to moderate ICCs for axial rotation. Adding more DOF to kinematic constraints did not improve performance in matching segmental angles. Kinematic constraints with 4-6DOF produced similar levels of smoothness across all tasks and generally improved smoothness compared to 9DOF or unconstrained (51DOF) models. Our results also revealed that the maximum joint ROMs predicted using 4-6DOF constraints were largely within physiologically acceptable ranges throughout the spine and in all directions of motions. We conclude that a kinematic constraint with 5DOF can produce smooth spine motions with physiologically reasonable joint ROMs and relatively low marker error.

Construct validity and internal consistency of the modified Persian version of the STarT Back Screening Tool.

BACKGROUND AND AIM: Considering the importance of non-specific low back pain (NSLBP) and its increasing spread, the need for instruments for the accurate diagnosis of back pain is evident in order to offer more effective treatment. One such instrument is the STarT Back Screening Tool (STarT) which is examined by numerous studies, while some of its psychometric dimensions still require attention. Therefore, the objective of this study was to assess the internal consistency and construct validity of this questionnaire to propose a modified version. METHOD: In this cross-sectional study, the data of 295 patients with NSLBP were analyzed. Cronbach's alpha was used to assess internal consistency, and exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to assess construct validity. The Χ2/df, GFI, CFI, and RMSEA indices were also utilized as the goodness-of-fit criteria. Data analysis was performed in SPSS, AMOS, and EQS programs. RESULTS: Goodness-of-fit indicators were calculated for the original Persian version of the questionnaire, showing an improper fit (RMSEA = 0.162). According to the measures of sampling adequacy (MSA) of the questions, Questions 1 and 8 were deleted, resulting in an improved index (RMSEA = 0.062). All the regression coefficients in the CFA model were significant (p < 0.001for all 7 parameters). CONCLUSION: Based on the results, the modified Persian version of the STarT is simpler and more practical than the previous version, serving as a valid and reliable tool for assessing patients with low back pain. With respect to the goodness-of-fit indices, we recommend that more studies with larger samples be conducted on different populations.

Validity of flexicurve and motion capture for measurements of thoracic kyphosis vs standing radiographic measurements.

Thoracic kyphosis varies among healthy adults and typically increases with age. Excessive kyphosis (hyperkyphosis) is associated with negative health. Spinal alignment also affects spine loading, with implications for conditions such as vertebral fractures and back pain. Valid measurements of kyphosis are necessary for clinical and research assessment of age-related posture changes, and to support improved biomechanical understating of spine conditions. Independent validation of non-radiographic techniques, however, remains limited. The goal of this study was to compare standing radiographic kyphosis measurements with non-radiographic measurements and predictions of thoracic kyphosis using flexicurve and motion analysis markers, in order to determine their validity. Thirteen non-radiographic measures of thoracic kyphosis were obtained in each of 40 adult subjects who also underwent standing radiographs of the thoracic spine. Measures included estimates derived by fitting of polynomials or circles to the non-radiographic data, as well as predictions calculated using previously published methods. Intra-class correlations (ICC) and root-mean square errors (RMSEs) were calculated between radiographic and non-radiographic measures to determine validity. Most non-radiographic estimates of kyphosis show similar, weak to moderate levels of validity when compared to radiographic measurements, and RMSEs ranging from 8.0° to 20.8°. Unbiased estimates of radiographic measurements with moderate to good ICCs were identified, however, based on marker measurements, and new prediction equations were created with similar validity that also account for age and body habitus. Clinical significance: These non-radiographic measurements of thoracic kyphosis can be applied to clinical practice or to clinical studies with recognition of specific limitations.

Design and Synthesis of Lipopolysaccharide-Binding Antimicrobial Peptides Based on Truncated Rabbit and Human CAP18 Peptides and Evaluation of Their Action Mechanism.

Lipopolysaccharide (LPS) is a toxic and immunogenic agent for human. Additionally, LPS is a good target for some antimicrobial compounds, including antimicrobial peptides (AMPs). LPS-binding peptides (LBPs) can recognize and neutralize LPS. Rabbit and human cathelicidins are AMPs with LPS-binding activity. In this study, we designed and synthesized two new truncated LBPs from rabbit and human CAP18 peptides by in silico methods. After synthesis of peptides, the antimicrobial properties and LPS-binding activity of these peptides were evaluated. The parental rabbit and human CAP18 peptides were selected as positive controls. Next, the changes in the secondary structure of these peptides before and after treatment with LPS were measured by circular dichroism (CD). Human cytotoxicity of the peptides was evaluated by MTT and red blood cells (RBCs) hemolysis assays. Finally, field emission scanning electron microscopy (FE-SEM), confocal microscopy, and flow cytometry were performed to study the action mechanism of these peptides. Results indicated that the hCap18 and rCap18 had antibacterial activity (at a MIC of 4-128 µg/mL). The results of the quantitative LAL test demonstrated that LPS-binding activity of hCap18 peptide was better than rCap18, while rCap18 peptide had better antimicrobial properties. Furthermore, rCap18 had less cytotoxicity than hCap18. However, both peptides were nontoxic for normal human skin fibroblast cell in MIC range. In conclusion, rCap18 has good antibacterial properties, while hCap18 can be tested as a diagnostic molecule in our future studies.

AurH1: a new heptapeptide derived from Aurein1.2 antimicrobial peptide with specific and exclusive fungicidal activity.

Due to the increasing incidence of fungal opportunistic infections and emergence of antibiotic-resistant fungal strains, antimicrobial peptides (AMPs) are considered as ideal candidates for antifungal compounds. In silico methods can reduce the limitations of natural AMPs such as toxicity and instability and improve their antimicrobial properties and selectivity. In this study, we designed AurH1, a new truncated peptide, based on the six-amino acid sequence of Aurein1.2. Further, the antimicrobial activities and toxicity effects of AurH1 on human skin fibroblast cells and red blood cells were investigated. Finally, field emission scanning electron microscopy (FE-SEM) and flow cytometry were performed in order to study the mechanism of action of AurH1. The results indicated that AurH1 had only antifungal activity (at a minimal inhibitory concentration (MIC) of 7.3-125 µg/mL) without any antibacterial effects on the selected bacteria, while Aurein1.2 had both antifungal and antibacterial activities as positive control. Furthermore, AurH1 did not show any toxicity on Hu02 cells and human red blood cells at its MIC range. In conclusion, it became clear that AurH1 is a selective peptide against fungi with no toxic effects on the selected bacteria and human cells.

Low back pain: Moving toward mechanism-based management.

Low back pain is a complex, multifactorial, and heterogeneous condition, but this does not make it an exception in medicine. Management of low back pain based on a mechanistic approach and developing more effective multidisciplinary treatment is possible and would finally implement the biopsychosocial model of care.

Between-session reliability of opto-electronic motion capture in measuring sagittal posture and 3-D ranges of motion of the thoracolumbar spine.

This study evaluated between-session reliability of opto-electronic motion capture to measure trunk posture and three-dimensional ranges of motion (ROM). Nineteen healthy participants aged 24-74 years underwent spine curvature, pelvic tilt and trunk ROM measurements on two separate occasions. Rigid four-marker clusters were attached to the skin overlying seven spinous processes, plus single markers on pelvis landmarks. Rigid body rotations of spine marker clusters were calculated to determine neutral posture and ROM in flexion, extension, total lateral bending (left-right) and total axial rotation (left-right). Segmental spine ROM values were in line with previous reports using opto-electronic motion capture. Intraclass correlation coefficients (ICC) and standard error of measurement (SEM) were calculated as measures of between-session reliability and measurement error, respectively. Retroreflective markers showed fair to excellent between-session reliability to measure thoracic kyphosis, lumbar lordosis, and pelvic tilt (ICC = 0.82, 0.63, and 0.54, respectively). Thoracic and lumbar segments showed highest reliabilities in total axial rotation (ICC = 0.78) and flexion-extension (ICC = 0.77-0.79) ROM, respectively. Pelvic segment showed highest ICC values in flexion (ICC = 0.78) and total axial rotation (ICC = 0.81) trials. Furthermore, it was estimated that four or fewer repeated trials would provide good reliability for key ROM outcomes, including lumbar flexion, thoracic and lumbar lateral bending, and thoracic axial rotation. This demonstration of reliability is a necessary precursor to quantifying spine kinematics in clinical studies, including assessing changes due to clinical treatment or disease progression.

Effects of cognitive load on the amount and temporal structure of postural sway variability in stroke survivors.

This study aimed to investigate the variability in postural sway patterns during quiet standing in stroke survivors. The postural sway was measured in 19 stroke survivors, as well as 19 healthy demographically matched participants, at 3 levels of postural difficulty (rigid surface with closed and open eyes, and foam surface with closed eyes), and 3 levels of cognitive difficulty (without a cognitive task, easy and difficult cognitive tasks). Both linear analyses (the amount of postural sway variability, including the standard deviation of the COP velocity in both the anteroposterior (AP) and mediolateral (ML) directions), as well as non-linear analyses [the temporal structure of the COP variability, including % Recurrence, % Determinism, Shannon Entropy, Trend and the maximum diagonal line (D max)] were employed. The results revealed that the amount of variability of the postural sway of stroke survivors was significantly greater than that of healthy participants, along both the ML and AP directions, with the highest obtained during standing on foam with closed eyes. All measures of the temporal structure of the COP variability were significantly greater in stroke survivors, as compared to the control group, along the ML direction, but not along the AP direction. The cognitive error was significantly higher during difficult cognitive tasks, although it was neither affected by postural difficulty nor by group. The different results obtained for the amount and temporal structure of the COP variability in the AP and ML directions shed light on the intricate mechanisms employed by the CNS in post-stroke balance control, and suggest that effective rehabilitative and therapeutic strategies should be patient-specific, taking both the environment/surface as well as the specific protocols into consideration.

Is There a Relationship Between Lumbar Proprioception and Low Back Pain? A Systematic Review With Meta-Analysis.

OBJECTIVE: To systematically review the relationship between lumbar proprioception and low back pain (LBP). DATA SOURCES: Four electronic databases (PubMed, EMBASE, CINAHL, SPORTDiscus) and reference lists of relevant articles were searched from inception to March-April 2014. STUDY SELECTION: Studies compared lumbar proprioception in patients with LBP with controls or prospectively evaluated the relationship between proprioception and LBP. Two reviewers independently screened articles and determined inclusion through consensus. DATA EXTRACTION: Data extraction and methodologic quality assessment were independently performed using standardized checklists. DATA SYNTHESIS: Twenty-two studies (1203 participants) were included. Studies measured lumbar proprioception via active or passive joint repositioning sense (JRS) or threshold to detection of passive motion (TTDPM). Data from 17 studies were pooled for meta-analyses to compare patients with controls. Otherwise, descriptive syntheses were performed. Data were analyzed according to measurement method and LBP subgroup. Active JRS was worse in patients compared with controls when measured in sitting (standard mean difference, .97; 95% confidence interval [CI], .31-1.64). There were no differences between groups measured via active JRS in standing (standard mean difference, .41; 95% CI, -.07 to .89) or passive JRS in sitting (standard mean difference, .38; 95% CI, -.83 to 1.58). Patients in the O'Sullivan flexion impairment subgroup had worse proprioception than the total LBP cohort. The TTDPM was significantly worse in patients than controls. One prospective study found no link between lumbar proprioception and LBP. CONCLUSIONS: Patients with LBP have impaired lumbar proprioception compared with controls when measured actively in sitting positions (particularly those in the O'Sullivan flexion impairment subgroup) or via TTDPM. Clinicians should consider the relationship between sitting and proprioception in LBP and subgroup patients to guide management. Further studies focusing on subgroups, longitudinal assessment, and improving proprioception measurement are needed.

Video-game based exercises for older people with chronic low back pain: a protocol for a feasibility randomised controlled trial (the GAMEBACK trial).

OBJECTIVES: To investigate the feasibility of implementing a video-game exercise programme for older people with chronic low back pain (LBP). DESIGN: Single-centred single-blinded randomised controlled trial (RCT). SETTING: Physiotherapy outpatient department in a public hospital in Western Sydney, Australia. PARTICIPANTS: We will recruit 60 participants over 55 years old with chronic LBP from the waiting list. INTERVENTIONS: Participants will be randomised to receive video-game exercise (n=30) or to remain on the waiting list (n=30) for 8 weeks, with follow up at 3 and 6 months. Participants engaging in video-game exercises will be unsupervised and will complete video-game exercise for 60minutes, 3 times per week. Participants allocated to remain on the waiting list will be encouraged to maintain their usual levels of physical activity. MAIN OUTCOME MEASURE: The primary outcomes for this feasibility study will be study processes (recruitment and response rates, adherence to and experience with the intervention, and incidence of adverse events) relevant to the future design of a large RCT. Estimates of treatment efficacy (point estimates and 95% confidence intervals) on pain self-efficacy, care seeking, physical activity, fear of movement/re-injury, pain, physical function, disability, falls-efficacy, strength, and walking speed, will be our secondary outcome measures. RESULTS: Recruitment for this trial began in November 2015. CONCLUSION: This study describes the rationale and processes of a feasibility study investigating a video-game exercise programme for older people with chronic LBP. Results from the feasibility study will inform on the design and sample required for a large multicentre RCT. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12615000703505.

Mental health status following severe sulfur mustard exposure: a long-term study of Iranian war survivors.

INTRODUCTION: This study aimed to describe the mental health status of sulfur mustard-exposed survivors suffering from severe respiratory and ophthalmological problems. METHODS: Out of 450 invited Iran-Iraq War survivors of sulfur mustard exposure with severe symptoms, 350 participated in this cross-sectional study. Mental health status was assessed using the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, criteria. Fisher exact test, Pearson chi-square test, and chi-square test were used to assess any relationship, and the independent-sample t test was employed to compare differences between the veterans with ocular and pulmonary injuries. RESULTS: There were 60.9% (n = 213) survivors who suffered from mental disorders. Among them, 39.7% (n = 139) were previously untreated and required the initiation of psychiatric treatment. The prevalence of anxiety and mood disorders among all survivors was 40.6% (n = 142) and 32.0% (n = 112), respectively. The most common anxiety and mood disorders were posttraumatic stress disorder (32.9%, n = 115) and major depressive disorder (22.3%, n = 78), respectively. Psychiatric disorders were more prevalent in cases with severe pulmonary chemical injury than in subjects with severe ophthalmologic chemical injury. Significant relationships were found between the types of psychiatric disorders and age, education, and occupation (P < .05). CONCLUSION: The psychiatric morbidity in the chemically injured populations was remarkable and significantly different between the populations. The prevalence of mental illness in these groups highlights the need for the appropriate provision of mental health services.

Molecular and Immunohistochemical Study of Platelet Derived Growth Factor Receptor Alpha in KIT Negative Gastrointestinal Stromal Tumors; the First Report from Iran.

BACKGROUND Gastrointestinal stromal tumors (GISTs) are potentially malignant tumors; however their behavior and response to treatment is dependent on the type of mutation and immunohistochemical expression of antigens. It is recommended to perform routine molecular and immunohistochemical tests in KIT and platelet derived growth factor receptor alpha (PDGFRA) molecules for making decision regarding targeted therapy and prediction of the behavior of the tumor. OBJECTIVES: There has been no study from Iran regarding the PDGFRA mutational analysis in GISTs. In this study, for the first time from Iran, we performed immunohistochemical and molecular analysis of PDGFRA molecule on GISTs. METHODS In a cross-sectional study during 7 years (2008-2014) on 50 untreated non-recurrent non-metastatic newly diagnosed GISTs, molecular analysis and immunohistochemical staining for PDGFRA were performed and findings were compared with different clinicopathological characteristics.. RESULTS During the 7 years, 50 cases of GISTs according to the above mentioned criteria were found. 17 cases were negative for KIT mutation. Of them, 15 (30%) were positive for either exon 12 or 18 mutation of PDGFRA. These cases showed more epithelioid morphology and the number of mitotic figures were lower than PDFRA negative GISTs. Also according to the criteria for risk assessment, it seems that PDGFRA mutant GISTs are rarely in the high risk category. CONCLUSION PDGFRA mutant GISTs are common in Iranian population and it is recommended to perform mutation analysis for PDGFRA in every GIST with wild type KIT and epithelioid morphology.

Is there a reliable and invariant set of muscle synergy during isometric biaxial trunk exertion in the sagittal and transverse planes by healthy subjects?

It has been suggested that the central nervous system simplifies muscle control through basic units, called synergies. In this study, we have developed a novel target-matching protocol and used non-negative matrix factorization (NMF) technique to extract trunk muscle synergies and corresponding torque synergies. Isometric torque data at the L5/S1 level and electromyographic patterns of twelve abdominal and back muscles from twelve healthy participants (five females) were simultaneously recorded. Each participant performed a total number of 24 isometric target-matching tasks using 12 different angular directions and 2 levels of uniaxial and biaxial exertions. Within- and between-subject similarities were assessed by considering both the data of different pairs of participants, where the activation coefficients of one participant were used in the NMF analysis of another participant, and the Pearson's correlation coefficients (R) between muscle synergy vectors. The results showed that, for a healthy person, a set of four muscles (overall variance accounted for (VAF) of 97.9 ± 0.53%) and four corresponding torque synergies (overall VAF of 92.2 ± 3.03%) could efficiently decompose the sagittal and transverse torque planes into their main directions. Furthermore, the correlation coefficients were 0.77 ± 0.12, 0.86 ± 0.08, 0.78 ± 0.12, and 0.93 ± 0.04, for all synergies, reflecting the consistency of muscle synergies across participants. Overall, our results suggest that by taking advantage of muscle synergies we could potentially overcome the redundancy inherent to control strategies of the trunk neuromuscular system. In future studies, the synergies identified in patients with low back pain could be compared with those extracted from healthy participants towards various clinical and rehabilitation applications.

Translation and validation of the Persian version of the STarT Back Screening Tool in patients with nonspecific low back pain.

OBJECTIVE: To translate the STarT Back Screening Tool (SBT) into Persian and to investigate the psychometric properties of the new version in a group of patients with Non-Specific Low Back Pain (NSLBP). BACKGROUND: The STarT is a validated questionnaire used for subgrouping LBP patients at three levels of low-, medium-, and high-risk, based on the risk of chronicity. It has previously been translated and validated in different languages. METHODS: The translation and validation of the original questionnaire were carried out in accordance with the standard guidelines. To approve the construct validity, 295 patients with NSLBP completed a questionnaire package. The package comprised of the STarT, Roland-Morris Disability questionnaire (RMDQ), Tampa Scale for Kinesiophobia (TSK), Coping Strategies Questionnaire (CSQ), and Hospital Anxiety and Depression Scale (HADS). To evaluate test-retest reliability, 35 randomly selected NSLBP patients completed the STarT questionnaire within min. 24-hour interval. RESULTS: Factor analysis confirmed two subscales of the STarT. The Cronbach α was .83 and .81 for the STarT and the subscale, respectively. This questionnaire showed excellent test-retest reliability (ICC = .85) (p < 0.01). The correlations between the STarT and RMDQ, CSQ, TSK, and the two subscales of HADS were estimated to be .81, .70, .71, .74, and .71, respectively. The Area under the Curve was also calculated for 6 items and the range was between .734 and .860. CONCLUSIONS: The Persian version of the STarT is reliable and valid, and consistent with the original questionnaire. Therefore, clinicians to subgroup Persian-speaking NSLBP patients can use it.

The effect of chronic low back pain on trunk accuracy in a multidirectional isometric tracking task.

STUDY DESIGN: A cross-sectional study to quantify trunk motor control during multidirectional isometric tracking tasks. OBJECTIVE: To investigate the effect of chronic low back pain (LBP) on trunk neuromuscular performance while participants performed isometric exertions of trunk muscles to track targets in different angles with various magnitudes. SUMMARY OF BACKGROUND DATA: Tracking tasks especially in multidirectional activities are among the common research methods to quantify human motor control in different conditions. However, little information is available on trunk motor control during these tasks. There is no study investigating trunk accuracy during multidirectional isometric tracking tasks in patients with LBP. MATERIALS AND METHODS: Twelve patients with chronic LBP and 16 asymptomatic participants performed isometric target tracking tasks in 12 different directions with varying magnitude, from 0% to 80% of individual maximum voluntary exertion, in upright standing posture. The tracking system included a moving target object that moved on a straight line in a predefined angle with the rate of 6% maximum voluntary exertion/s. Trunk accuracy was quantified by computing constant error and variable error during each trial. A mixed model repeated measure analysis of variance was conducted to assess statistical analysis. RESULTS: Patients with chronic LBP track the target object with higher error compared with healthy controls across almost all of the target angles (P < 0.01). Trunk accuracy decreased significantly in higher level of exertions (P < 0.01). CONCLUSION: The results provided additional evidence of a change in trunk control strategies in patients with chronic LBP. Decreased accuracy of trunk during isometric tracking tasks especially in higher levels of asymmetric exertions may explain higher risk of low back injuries in these activities. LEVEL OF EVIDENCE: 4.