Non-invasive measurement of the patellofemoral movements during knee extension–flexion: A validation study

BackgroundThis study compared the difference between patellofemoral kinematics derived simultaneously from patellar bone pin and skin sensors during full range of tibiofemoral joint movement.MethodsMovements at the tibiofemoral and patellofemoral joints during passive full extension–flexion of the knees in three un-embalmed human cadavers were studied with four electromagnetic tracking sensors at a sampling rate of 30 Hz. A total of four sensors were attached on distal femur, proximal tibia, the surface of a tailor-made patella mold and at the tip of a plastic bone pin planted in the patellar body through a window on the mold. Paired-sample Wilcoxon signed rank test was used to compare peak motions computed from different sensors. The correlation of the movement–time curves derived from different sensors was tested by coefficient of multiple correlations (CMC) in different sections of tibiofemoral joint range.ResultsPeak motions detected by skin sensor for patellar lateral tilt (p = 0.045), distal translation (p = 0.021), lateral shift (p = 0.032), and anterior–posterior shift of patella (p = 0.03 and 0.01 respectively) were higher than that by the bone pin sensor. The overall CMC values for anterior–posterior translation and medial–lateral shift were lower than movements in other planes of movement. The CMC values in initial range were higher than that in the middle and end range in all planes of movement.ConclusionsPatellofemoral kinematics derived from skin sensors may not be representative of the underlying patellar motion. Kinematics reported from the skin sensors should be carefully interpreted.     

Determination of backrest inclination based on biodynamic response study for prevention of low back pain

Whole-body vibration experiments with subjects under vertical vibration were performed to examine and evaluate effects of backrest inclination on vibration transmitted through seats to the human body by using biodynamic response parameters represented by apparent mass (APMS) and vibration power absorption (VPA). The biodynamic response parameters of twelve male subjects, exposed to vertical random vibration at 0.8 m/s² r.m.s., were characterized under three different backrest support conditions, with the upper body supported against backrest inclined at angles of 0° (vertical), 10°, and 30° with respect to the vertical axis. An increased backrest inclination angle resulted in reduction of the total power absorption calculated particularly the frequency range of 1–20 Hz. Normalized APMS magnitudes showed a principal resonance at about 5 Hz for each subject for a backrest supported vertically. A second resonant peak appeared at about 7.5 Hz in addition to the primary resonant peak for a backrest inclined at an angle of 10° and then became much steeper for a backrest inclined at angle of 30°. For a backrest inclined at an angle of 30°, the resonant peak at 5 Hz was less apparent than in other backrest inclination postures. All subjects showed the second resonant peak at about 7.5 Hz in the double-normalized VPA for a backrest inclined at an angle of 30°. According to the evaluation of vibration absorption behavior performed in this study, backrest inclination angle is preferable between 10° and 30° from the viewpoint of prevention of low back pain disorder.     

Can a single lower trunk body-fixed sensor differentiate between level-walking and stair descent and ascent in older adults? Preliminary findings

Stair ascent and descent are common forms of ambulation that may be challenging to detect. Here, we propose the first step towards differentiating between stair negotiation and level-walking using a single body-fixed sensor.Seventeen healthy older adults (age: 79.3 ± 4.2 years, 47% women) wore a body-fixed sensor on the lower-back while performing level-walking and stair negotiation. Measures derived from the 3D acceleration and angular-velocity signals included medians, ranges, step duration, step and stride regularity, filtered vertical to horizontal acceleration ratio (VAF/HAF), and wavelet-based features. Friedman's and Wilcoxon tests compared between conditions. Stepwise-binary logistic-regression evaluated classification accuracy.During level-walking, yaw range was lowest and anterior–posterior and vertical step and stride regularity were highest (p ≤ 0.007). Anterior–posterior step regularity (p = 0.003), VAF/HAF (p = 0.094), and yaw range (p = 0.105) identified level-walking (92.2% accuracy). During stair ascent, roll range, median anterior–posterior acceleration and anterior–posterior wavelet-coefficient were lowest (p ≤ 0.006), while VAF/HAF was highest (p = 0.0029). Anterior posterior wavelet coefficient (p = 0.038) and VAF/HAF (p = 0.018) identified stair ascent (94.3% accuracy). During stair descent, vertical and medio-lateral ranges were highest and medio-lateral stride regularity and VAF/HAF were lowest (p ≤ 0.006). VAF/HAF (p = 0.01), medio-lateral acceleration range (p = 0.069), and medio-lateral stride regularity (p = 0.072) identified stair descent (90.2% accuracy).These findings suggest that a single worn body-fixed sensor can be used to differentiate between level-walking and stair negotiation.     

Low frequency of Fabry disease in patients with common heart disease

PurposeTo test the hypothesis that undiagnosed patients with Fabry disease exist among patients affected by common heart disease.MethodsGlobotriaosylceramide in random whole urine using tandem mass spectroscopy, α-galactosidase A activity in dried blood spots, and next-generation sequencing of pooled or individual genomic DNA samples supplemented by Sanger sequencing.ResultsWe tested 2,256 consecutive patients: 852 women (median age 65 years (19–95)) and 1,404 men (median age 65 years (21–92)). The primary diagnoses were coronary artery disease (n = 994), arrhythmia (n = 607), cardiomyopathy (n = 138), and valvular disease (n = 568). Urinary globotriaosylceramide was elevated in 15% of patients and 15 males had low α-galactosidase A activity. GLA variants found included R118C (n = 2), D83N, and D313Y (n = 7); IVS6-22 C>T, IVS4-16 A>G, IVS2+990C>A, 5′UTR-10 C>T (n = 4), IVS1-581 C>T, IVS1-1238 G>A, 5′UTR-30 G>A, IVS2+590C>T, IVS0-12 G>A, IVS4+68A>G, IVS0-10 C>T, IVS2-81–77delCAGCC, IVS2-77delC. Although the pathogenicity of several of these missense mutations and complex intronic haplotypes has been controversial, none of the patients screened in this study were diagnosed definitively with Fabry disease.ConclusionThis population of patients with common heart disease did not contain a substantial number of patients with undiagnosed Fabry disease. GLA gene sequencing is superior to urinary globotriaosylceramide or α-galactosidase A activity in the screening for Fabry disease.     

Adding “hemodynamic and fluid leads” to the ECG. Part I: The electrical estimation of BNP,chronic heart failure (CHF) and extracellular fluid (ECF) accumulation

ObjectivesIn primary care the diagnosis of CHF and ECF accumulation is no triviality. We aimed to predict plasma BNP, CHF and ECF accumulation with segmental impedance spectroscopy while using and extending the electrodes of the conventional electrocardiography.MethodsThree combined multiple electrodes were added to the 15 lead ECG for segmental impedance spectroscopy and for measuring the maximal rate of segmental fluid volume change with heart action at the thorax and the legs. The obtained signals were analyzed by partial correlation analyses in comparison with plasma BNP, CHF classes, ejection fraction by echocardiography and cardiac index by double gas re-breathing. 119 subjects (34 healthy volunteers, 50 patients with CHF, NYHA classes II to IV and 35 patients without CHF) were investigated.ResultsThe maximal rate of volume change with heart action at the thorax and at the legs, as well as the ECF/ICF ratio at the legs contribute equally and independently to the prediction of BNP and heart failure in an unknown test sample of 49 patients (multiple r = 0.88, p < 0.001). The ROC-curve for the predicted plasma BNP > 400 pg/ml gave an AUC = 0.93. The absence or the presence of heart failure could be predicted correctly by a binomial logistic regression in 92.9 and 87.5% of cases, respectively.ConclusionThe methodology, which is based on inverse coupling of BNP release and of maximal blood acceleration and on sensitive detection of ECF overload, could enable the diagnosis of CHF with useful sensitivity and specificity while writing a routine-ECG.     

The long leg radiograph is a reliable method of assessing alignment when compared to computer-assisted navigation and computer tomography

BackgroundThe mechanical alignment of the knee is an important factor in planning for, and subsequently assessing the success of a knee replacement. It is most commonly measured using a long-leg anteroposterior radiograph (LLR) encompassing the hip, knee and ankle. Other modalities of measuring alignment include computer tomography (CT) and intra-operative computer navigation (Cas). Recent studies comparing LLRs to Cas in measuring alignment have shown significant differences between the two and have hypothesized that Cas is a more accurate modality. This study aims to investigate the accuracy of the above mentioned modalities.MethodologyA prospective study was undertaken comparing alignment as measured by long-leg radiographs and computer tomography to intra-operative navigation measurements in 40 patients undergoing a primary total knee replacement to test this hypothesis. Alignment was measured three times by three observers. Intra- and inter-observer correlation was sought between modalities.ResultsIntra-observer correlation was excellent in all cases (> 0.98) with a coefficient of repeatability < 1.1°. Inter-observer correlation was also excellent measuring > 0.960 using LLRs and > 0.970 using CT with coefficient of repeatability < 2.8°. Inter-modality correlation proved to be higher when comparing LLRs and CT (> 0.893), than when comparing either of these modalities with Cas (> 0.643 and > 0.671 respectively). Pre-operative values had the greatest variability.ConclusionGiven its availability and reduced radiation dose when compared to CT, LLRs should remain the mainstay of measuring the mechanical alignment of the lower limb, especially post-operatively.Level of evidenceII     

Discrete sensors distribution for accurate plantar pressure analyses

The aim of this study was to determine the distribution of discrete sensors under the footprint for accurate plantar pressure analyses. For this purpose, two different sensor layouts have been tested and compared, to determine which was the most accurate to monitor plantar pressure with wireless devices in research and/or clinical practice. Ten healthy volunteers participated in the study (age range: 23–58 years). The barycenter of pressures (BoP) determined from the plantar pressure system (W-inshoe®) was compared to the center of pressures (CoP) determined from a force platform (AMTI) in the medial-lateral (ML) and anterior-posterior (AP) directions. Then, the vertical ground reaction force (vGRF) obtained from both W-inshoe® and force platform was compared for both layouts for each subject. The BoP and vGRF determined from the plantar pressure system data showed good correlation (SCC) with those determined from the force platform data, notably for the second sensor organization (ML SCC= 0.95; AP SCC = 0.99; vGRF SCC = 0.91). The study demonstrates that an adjusted placement of removable sensors is key to accurate plantar pressure analyses. These results are promising for a plantar pressure recording outside clinical or laboratory settings, for long time monitoring, real time feedback or for whatever activity requiring a low-cost system.     

Prolonged breast-feeding is an independent risk factor for postmenopausal osteoporosis

ObjectivesThis study investigated the effects of parity and age at first pregnancy and breast-feeding, as well as duration of BF for total and per child on postmenopausal osteoporosis.Study designThe study was conducted among 542 cases who were divided based on the presence or absence of osteoporosis. Patients were separated according to their first pregnancy and breast-feeding age as before or after 27 years. Osteoporosis was defined as a T score of ?2.5 or lower.Main outcome measuresParity, age at first pregnancy and breast-feeding, breast-feeding period for total and average duration per child according to a questionnaire were assessed.ResultsOsteoporosis group had significantly lower parity compared to non-osteoporosis group. The age at first pregnancy and breast-feeding < 27 age were significantly more frequent in osteoporosis group. They also had prolonged breast-feeding period. Women who had a breast-feeding period per child > 1 year under age 27 was higher in osteoporosis group. In multivariate analysis, women who breast-fed > 1 year per child had the highest risk for osteoporosis (odds ratio: 12.92; 95% confidence interval, 3.1–52.6) and osteoporosis risk for women who breast-fed > 1 year per child under age 27 was 7.1. Increased parity was associated with a significant protective effect for osteoporosis.ConclusionsExtended breast-feeding period per child > 1 year is the highest risk factor for osteoporosis independent of first breast-feeding age. However, high parity has a protective effect.     

Association of inhibin α gene promoter polymorphisms with risk of idiopathic primary ovarian insufficiency in Korean women

ObjectiveThe aim of this study was to investigate whether two polymorphisms in the promoter region of inhibin alpha (INHA) are associated with risk of idiopathic primary ovarian insufficiency (POI) in Korean women, which is a controversial topic.Study designWe genotyped the INHA polymorphisms c.-16C > T (rs35118453) and c.-124A > G (rs11893842) of 136 POI patients and 225 controls in Korean women by polymerase chain reaction and restriction fragment length polymorphism analysis. We then compared differences in genotype and allele frequencies (AF) of the polymorphisms between the two groups to determine odds ratios (OR) and 95% confidence intervals (CI) as measures of the strength of association between genotype and POI.ResultsThere were no significant differences in genotype or AF of the polymorphisms between the POI patients and controls. Haplotype analysis revealed that the T–G haplotype of the two variant alleles was more frequent in POI patients than in the controls (OR = 1.630, 95% CI = 1.081–2.457). Combination genotype analysis showed that the CT + TT/GG genotype frequency was higher in POI patients than in the controls (OR = 2.414, 95% CI = 1.190–4.895).ConclusionsWe provide evidence to suggest that when the two variant alleles are combined, the c.-16C > T and c.-124A > G polymorphisms are associated with increased POI risk in Korean women. We postulate that interactions between the INHA polymorphisms may affect POI risk.     

The effect of vertical whole-body vibration on lower limb muscle activation in elderly adults: Influence of vibration frequency,amplitude and exercise

ObjectiveThis study aimed to investigate how whole-body vibration (WBV) and exercise and their interactions influenced leg muscle activity in elderly adults.Study designAn experimental study with repeated measures design that involved a group of ambulatory, community-dwelling elderly adults (n = 30; 23 women; mean age = 61.4 ± 5.3 years).Main outcome measuresMuscle activity of the vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), and gastrocnemius (GS) was measured by surface electromyography (EMG), while participants were performing seven different exercises during 4 WBV conditions (condition 1: frequency = 30 Hz, amplitude = 0.6 mm, intensity = 2.25 units of Earth’s gravity (g); condition 2: 30 Hz, 0.9 mm, 3.40 g; condition 3: 40 Hz, 0.6 mm, 3.65 g; condition 4: 40 Hz, 0.9 mm, 5.50 g) and a no-WBV condition in a single experimental session.ResultsSignificantly greater muscle activity was recorded in VL (3%–148%), BF (16%–202%), and GS (19% –164%) when WBV was added to the exercises, compared with the same exercises without WBV (p ≤ 0.015). The effect of vibration intensity on EMG amplitude was exercise-dependent in VL (p = 0.002), and this effect was marginally significant in GS (p = 0.052). The EMG activity induced by the four WBV intensities was largely similar, and was the most pronounced during static erect standing and static single-leg standing.ConclusionsThe EMG amplitude of majority of leg muscles tested was significantly greater during WBV exposure compared with the no-WBV condition. Low-intensity WBV can induce muscle activity as effectively as higher-intensity protocols, and may be the preferred choice for frail elderly adults.     

Relationship between perilipin gene polymorphisms and body weight and body composition during weight loss and weight maintenance

BackgroundGenetic variation in the perilipin (PLIN) gene may play a role in the etiology and treatment of obesity.ObjectiveTo examine different polymorphisms in the PLIN gene in relation to body-weight regulation.Methods118 subjects followed a 6 wk VLCD, followed by 1 year weight maintenance. Body-weight (BW), body-composition, leptin concentration, and polymorphisms of the PLIN gene: PLIN1:rs2289487, PLIN4:rs894160, PLIN6:rs1052700, PLIN5:rs2304795 and PLIN7:rs 2304796 were determined.ResultsBW loss during VLCD was 7.0 ± 3.1 kg (p < 0.05), and BW regain was 3.7 ± 1.4 kg (p < 0.05), including changes in body mass index (BMI), waist-circumference, body-composition and leptin concentrations (p < 0.05).Linkage disequilibria were observed between PLIN1 and PLIN4: D' > 0.9, r² = 0.72; PLIN5 and PLIN7: D' > 0.9, r² = 0.85.In men, body weight, BMI, waist circumference, body fat, leptin concentrations were significantly lower for the haplotype of PLIN1 (C-alleles) and PLIN4 (A-alleles). In women weight loss and loss of fat mass were larger for the haplotype of PLIN1 (C-alleles) and PLIN4 (A-alleles). For PLIN6 genotypes body weight and body fat were lower for homozygotes of the minor allele (T/T) in the men; in the women leptin concentrations were lower.The haplotype of PLIN5 and PLIN7 consisting of A/G and G/G of PLIN5 and A/A of PLIN7 showed a reduction in FM: 5.9 ± 0.6 kg vs 3.1 ± 0.4 kg, % body fat: 5.5 ± 0.6% vs 2.2 ± 0.2%, and leptin: 20.5 ± 10.8 ng/ml vs 12.9 ± 6.7 ng/ml over time in the women (p < 0.05).ConclusionSince the haplotype of the minor alleles PLIN1–4, PLIN5–7 and PLIN6, was related to body-weight regulation at a lower level of body-weight in the men as well in the women we conclude that the PLIN1–4, 6, and 5–7 locus appears as a genetic influencer of obesity risk in humans.     

Proteomic investigation of cultivated fibroblasts from patients with mitochondrial short-chain acyl-CoA dehydrogenase deficiency

Short-chain acyl-CoA dehydrogenase (SCAD) deficiency is a rare inherited autosomal recessive disorder with not yet well established mechanisms of disease. In the present study, the mitochondrial proteome of five symptomatic patients homozygous for missense variations in the SCAD gene ACADS was investigated in an extensive large-scale proteomic study to map protein perturbations linked to the disease.Fibroblast cultures of patient cells homozygous for either c.319C>T/p.Arg107Cys (n = 2) or c.1138C>T/p.Arg380Trp (n = 3) in ACADS, and healthy controls (normal human dermal fibroblasts), were studied. The mitochondrial proteome derived from these cultures was analyzed by label free proteomics using high mass accuracy nanoliquid chromatography tandem mass spectrometry (nanoLC–MS/MS).More than 300 mitochondrial proteins were identified and quantified. Thirteen proteins had significant alteration in protein levels in patients carrying variation c.319C>T in ACADS compared to controls and they belonged to various pathways, such as the antioxidant system and amino acid metabolism. Twenty-two proteins were found significantly altered in patients carrying variation c.1138C>T which included proteins associated with fatty acid β-oxidation, amino acid metabolism and protein quality control system. Three proteins were found significantly regulated in both patient groups: adenylate kinase 4 (AK4), nucleoside diphosphate kinase A (NME1) and aldehyde dehydrogenase family 4 member A1 (ALDH4A1). Proteins AK4 and NME1 deserve further investigation because of their involvement in energy reprogramming, cell survival and proliferation with relevance for SCAD deficiency and related metabolic disorders.     

Spatial summation of vibrotactile sensations at the foot

Thresholds for the perception of vibration on the hand reduce with increasing area of excitation when the thresholds are mediated by the Pacinian channel (a phenomenon known as spatial summation) but thresholds are generally independent of the area of excitation when they are mediated by non-Pacinian channels. The effect of the area of excitation on vibrotactile thresholds at the sole of the foot has not been thoroughly investigated. In the study reported in this paper, thresholds for the perception of 20 Hz vibration and 160 Hz vibration were determined on the foot (at the big toe (hallux), the medial (inside) ball, the lateral (outside) ball, and the heel) and on the hand (at the thenar eminence and at the fingertip) in 12 male subjects using four probe diameters: 1 mm (0.19 cm² excitation area), 3 mm (0.38 cm²), 6 mm (0.78 mm²) and 10 mm (1.53 cm²) with a 2 mm gap between the vibrating probe and a fixed surround. On both the hand and the foot, thresholds for the perception of 160 Hz vibration decreased as the probe diameter increased. There was no overall consistent change in thresholds for the perception of 20 Hz vibration. Thresholds for the perception of 160 Hz vibration were lowest at the fingertip and highest at the big toe. Thresholds for 20 Hz vibration were also lowest at the fingertip. It is concluded that on the sole of the foot there is evidence of spatial summation in the perception of 160 Hz vibration, mediated by the Pacinian channel, but not in the perception of 20 Hz vibration, mediated by a non-Pacinian channel. The findings show that vibrotactile thresholds at the foot obtained with different areas of excitation, or an unknown area of excitation, should not be compared. It is concluded that there is a need to standardise methods of measuring the vibrotactile thresholds at the foot that are obtained for clinical applications.     

Agreement of skin test with IL-4 production and CD40L expression by T cells upon immunotherapy of subjects with systemic reactions to Hymenoptera stings

Venom immunotherapy is the only curative intervention for subjects with Hymenoptera venom allergy who suffering systemic reactions upon bee or wasp stings. Venom immunotherapy can restore normal immunity against venom allergens, as well as providing to allergic subjects a lifetime tolerance against venoms. Nevertheless, it is necessary using safety assays to monitoring the development of tolerance in the VIT protocols to avoid fatal anaphylactic reactions. The purpose of this study was to assess the modifications in several markers of tolerance induction in subjects with Hymenoptera venom allergy undergoing immunotherapy. The studies were performed at baseline time and after six month of VIT. Intradermal skin tests, basophil activation tests, specific IgE levels; and the T-cell markers (IL-4 and IFN-γ producing cells; and expression of the surface activation markers CD40L and CTLA-4) were assayed. At six month of imunotherapy all parameters studied had significant alterations. All decreased, except the IFN-γ producing cells. In addition, modifications in intradermal skin test showed a significant correlation with both, CD40L expression on CD4 T lymphocytes (p = 0.043) and IL-4 producing T lymphocytes (p = 0.012). Neither basophil activation test nor serum levels of sIgE demonstrated any correlation with the immunological parameters studied nor among them. These results suggest that both IL-4 production and CD40L expression could be two good indicators of the beneficial effects of venom immunotherapy which translate into skin tests.     

Filtering and thresholding the analytic signal envelope in order to improve peak and spike noise reduction in EEG signals

To remove peak and spike artifacts in biological time series has represented a hard challenge in the last decades. Several methods have been implemented mainly based on adaptive filtering in order to solve this problem. This work presents an algorithm for removing peak and spike artifacts based on a threshold built on the analytic signal envelope. The algorithm was tested on simulated and real EEG signals that contain peak and spike artifacts with random amplitude and frequency occurrence. The performance of the filter was compared with commonly used adaptive filters. Three indexes were used for testing the performance of the filters: Correlation coefficient (ρ), mean of coherence function (C), and rate of absolute error (RAE). All these indexes were calculated between filtered signal and original signal without noise. It was found that the new proposed filter was able to reduce the amplitude of peak and spike artifacts with ρ > 0.85, C > 0.8, and RAE < 0.5. These values were significantly better than the performance of LMS adaptive filter (ρ < 0.85, C < 0.6, and RAE > 1).     

Association of nitric oxide synthase gene polymorphisms (−786T>C, 4a4b, 894G>T) with primary ovarian insufficiency in Korean women

ObjectivesThe aim of our study was to investigate whether the endothelial nitric oxide synthase (eNOS) gene polymorphisms ?786T>C, 4a4b, and 894G>T that affect nitric oxide (NO) generation confer a risk for primary ovarian insufficiency (POI) in Korean women.Study designWe genotyped 136 POI patients and 236 controls among Korean women for the three single nucleotide polymorphism sites with PCR-RFLP analysis. Differences in the eNOS ?786T>C (rs2070744), 4a4b (rs61722009), and 894G>T (rs1799983) genotype frequencies between patients and controls were compared, and odds ratios and 95% confidence intervals were determined as a measure of the strength of the association between the genotypes and POI.ResultsThe POI patients had significantly decreased frequencies of the eNOS 894GT and ?786TT/894GT genotypes (P = 0.025 and 0.027, respectively). However, the significant association between these eNOS polymorphisms and POI disappeared after adjustment for multiple comparisons (adjusted P = 0.075 and 0.081, respectively). The eNOS ?786T/894G haplotype is more frequent in patients than controls (P = 0.030), whereas the ?786T/894T haplotype was less frequent in patients (P = 0.031). The associations between ?786/894 haplotypes and POI were confirmed by permutation tests. We did not find associations between the eNOS ?786T>C or 4a4b polymorphisms and POI.ConclusionsOur data suggest that the eNOS ?786T/894T haplotype is associated with a decreased POI risk, and we postulate that the eNOS ?786T/894T haplotype may confer less risk on POI occurrence by reducing pathologically increased NO generation by eNOS in POI. Further study is warranted to elucidate the effect of the eNOS 894G>T polymorphism and POI occurrence.     

High concentrations of anti-caspase-8 antibodies in Chilean patients with type 1 diabetes

IntroductionDeregulation of apoptosis across the Fas–FasL pathway is an increasingly relevant phenomenon in the pathogenic mechanisms associated with autoimmune diseases. Caspase-8 initiates the activation of the apoptotic process and interacts directly with Fas in the membrane of the T lymphocyte.ObjectivesTo standardize an Elisa essay to measure the concentration of anti-caspase-8 antibodies in plasma of Type 1 Diabetes (T1D) patients and analyze their possible distribution and association with characteristics of the disease.Methods and subjects124 patients newly diagnosed with T1D and 132 controls: children and youngsters. ELISA test was standardized to detect anti-caspase-8 antibodies in plasma. It correlated the concentration of this antibody with classical markers of autoimmunity as anti-IA-2 and anti-GAD65, and the clinical characteristics at onset of diabetes mellitus. The statistical analysis was performed using logistic regression.ResultsPatients with T1D showed a higher concentration of anti-caspase-8 antibodies regarding the controls (87.5 ng/ml versus 24.3 ng/ml, p < 0.0001, values expressed as median). The proportion of patients with T1D and high concentrations of anti-caspase-8 (percentile 50–75) was significantly different from the control group (p < 0.0001). Anti-caspase-8 showed a strong association with positive anti-GAD65 (OR = 3.48, p < 0.035) and ketoacidosis (OR = 10.74, p < 0.0001) events, with glycemia and age at diagnosis as contributing variables.ConclusionThis is the first report in the literature of levels of anti-caspase-8 antibodies in T1D through ELISA. The high concentration in patients with T1D, and its strong correlation with anti-GAD65 auto-antibodies, suggests a potential role of anti-caspase-8 auto-antibodies as surrogate marker autoimmunity in T1D patients.     

The association of PTPN22 (rs2476601) and IL2RA (rs11594656) polymorphisms with T1D in Egyptian children

BackgroundType 1 diabetes mellitus (T1D) is a T cell-mediated autoimmune disease characterized by the destruction of pancreatic β cells. PTPN22 and IL2RA polymorphisms have been found to be associated with several autoimmune diseases including T1D.AimsWe aimed to elucidate the role of PTPN22 and IL2RA polymorphisms in predisposition of T1D in Egyptian children.MethodsWe studied 150 children and adolescents with T1D and 165 healthy controls. The PTPN22 (rs2476601) and IL2RA (rs11594656) polymorphisms were genotyped using polymerase chain reaction.ResultsWe found that carriers of the T allele of PTPN22 were significantly more likely to develop T1D (OR = 2.2, 95% CI = 1.2–4, P = 0.01). Also, the carrier of TT genotype and T allele of IL2RA more likely to develop T1D (OR = 2.8, 1.4, respectively, P = 0.03). There was a statistically significant association between T allele of PTPN22 gene and females ⩽10 years old at the onset of diabetes (OR = 4, 95% CI = 1.2–13.4, P = 0.019).ConclusionThis study suggests a possible association between the T allele of PTPN22 gene and TT genotype of IL2RA with T1D in studied Egyptian children, especially, females with early onset diabetes who carried the 1858T allele.     

Reliability,validity, and precision of an active stereophotogrammetry system for three-dimensional evaluation of the human torso

To determine the reliability, stability, validity and precision of a stereophotogrammetry (SP) system for use in quantifying the complex three-dimensional structure of the human torso, we performed assessments of the system using images of geometric solids and a human-form mannequin. Analysis of geometric solids revealed excellent intra- and interrater reliability of the system for linear, surface area and volume measurements (r > 0.99, P < 0.001). Overall, no significant difference was found between SP and manual measurements (F = 4.23, P > 0.06). The system exhibited excellent stability in images of the mannequin over time (r > 0.99). The limit of precision (error > 5%) of the system to detect objects on the surface of the mannequin was estimated at an object size of 23.5 cm² for surface area and 32 mL for volume. These results demonstrate the capability of SP of the torso to be used as a reliable, stable and valid measure of torso morphology to be applied as a clinical outcome tool in studies of bony and soft tissue pathologies such as scoliosis, rib deformities, obesity or edema.