The role of hip abductor strength on the frontal plane of gait in subjects with medial knee osteoarthritis

Objective: This study aimed to investigate the relationship of hip abductor strength with external hip and knee adduction moments, pain and physical function, and trunk, pelvis, and hip kinematics in the frontal plane during walking in subjects with medial knee osteoarthritis. Methods: Twenty-five subjects with medial knee osteoarthritis were evaluated through an isokinetic strength test for hip abductor, three-dimensional gait analysis (kinetics and kinematics), pain and physical function scores. Regression models were used to control the influence of other parameters such as pain, age, gender, severity, walking speed, mass and height. Results: No relationship was found of hip abductor strength with peak of external knee adduction moment and knee adduction angular impulse. Hip abductor strength explained 17% of contralateral pelvic drop and 21% of hip adduction angle. In addition, hip abductor strength explained 4% and 1% of the variance in the WOMAC physical function score and 40 meter fast paced walk test, respectively. Conclusion: Considering the relationship of hip abductor strength with contralateral pelvic drop and hip adduction angle, specific exercises might improve physical function and lower limb dynamic alignment during gait

The relationship between urinary C-Telopeptide fragments of type II collagen, knee joint load, pain, and physical function in individuals with medial knee osteoarthritis

Objective: Considering the osteoarthritis (OA) model that integrates the biological, mechanical, and structural components of the disease, the present study aimed to investigate the association between urinary C-Telopeptide fragments of type II collagen (uCTX-II), knee joint moments, pain, and physical function in individuals with medial knee OA. Methods: Twenty-five subjects radiographically diagnosed with knee OA were recruited. Participants were evaluated through three-dimensional gait analysis, uCTX-II level, the WOMAC pain and physical function scores, and the 40m walk test. The association between these variables was investigated using Pearson´s product-moment correlation, followed by a hierarchical linear regression, controlled by OA severity and body mass index (BMI). Results: No relationship was found between uCTX-II level and knee moments. A significant correlation between uCTX-II level and pain, physical function, and the 40m walk test was found. The hierarchical linear regression controlling for OA severity and BMI showed that uCTX-II level explained 9% of the WOMAC pain score, 27% of the WOMAC physical function score, and 7% of the 40m walk test. Conclusion: Greater uCTX-II level is associated with higher pain and reduced physical function and 40m walk test performance in individuals with medial knee OA

DirtyGenes: testing for significant changes in gene or bacterial population compositions from a small number of samples

High throughput genomics technologies are applied widely to microbiomes in humans, animals, soil and water, to detect changes in bacterial communities or the genes they carry, between different environments or treatments. We describe a method to test the statistical significance of differences in bacterial population or gene composition, applicable to metagenomic or quantitative polymerase chain reaction data. Our method goes beyond previous published work in being universally most powerful, thus better able to detect statistically significant differences, and through being more reliable for smaller sample sizes. It can also be used for experimental design, to estimate how many samples to use in future experiments, again with the advantage of being universally most powerful. We present three example analyses in the area of antimicrobial resistance. The first is to published data on bacterial communities and antimicrobial resistance genes (ARGs) in the environment; we show that there are significant changes in both ARG and community composition. The second is to new data on seasonality in bacterial communities and ARGs in hooves from four sheep. While the observed differences are not significant, we show that a minimum group size of eight sheep would provide sufficient power to observe significance of similar changes in further experiments. The third is to published data on bacterial communities surrounding rice crops. This is a much larger data set and is used to verify the new method. Our method has broad uses for statistical testing and experimental design in research on changing microbiomes, including studies on antimicrobial resistance

A transcriptome-wide association study among 97,898 women to identify candidate susceptibility genes for epithelial ovarian cancer risk

Large-scale genome-wide association studies (GWAS) have identified approximately 35 loci associated with epithelial ovarian cancer (EOC) risk. The majority of GWAS-identified disease susceptibility variants are located in non-coding regions, and causal genes underlying these associations remain largely unknown. Here we performed a transcriptome-wide association study to search for novel genetic loci and plausible causal genes at known GWAS loci. We used RNA sequencing data (68 normal ovarian-tissue samples from 68 individuals and 6,124 cross-tissue samples from 369 individuals) and high-density genotyping data from European descendants of the Genotype-Tissue Expression (GTEx V6) project to build ovarian and cross-tissue models of genetically regulated expression using elastic net methods. We evaluated 17,121 genes for their cis-predicted gene expression in relation to EOC risk using summary statistics data from GWAS of 97,898 women, including 29,396 EOC cases. With a Bonferroni-corrected significance level of P<2.2×10-6, we identified 35 genes including FZD4 at 11q14.2 (Z=5.08, P=3.83×10-7, the cross-tissue model; 1 Mb away from any GWAS-identified EOC risk variant), a potential novel locus for EOC risk. All other 34 significantly-associated genes were located within 1 Mb of known GWAS-identified loci, including 23 genes at 6 loci not previously linked to EOC risk. Upon conditioning on nearby known EOC GWAS-identified variants, the associations for 31 genes disappeared and 3 genes remained (P<1.47 x 10-3). These data identify one novel locus (FZD4) and 34 genes at 13 known EOC risk loci associated with EOC risk, providing new insights into EOC carcinogenesis

Relação entre a lesão condral e o pico de torque após reconstrução do ligamento cruzado anterior do joelho: estudo de casos Relationship between chondral lesion and peak torque following anterior cruciate ligament reconstruction of the knee: case study

CONTEXTUALIZAÇÃO: A associação entre lesão do ligamento cruzado anterior (LCA) e desenvolvimento de osteoartrite (OA) secundária tem sido objeto de vários estudos. A lesão ligamentar predispõe a lesões da cartilagem articular, influenciando, assim, o controle motor e o pico de torque. OBJETIVO: Avaliar a influência do grau de lesão condral no pico de torque da musculatura anterior e posterior da coxa após lesão e reconstrução do LCA. MÉTODO: Seis sujeitos do sexo masculino com lesão total e unilateral do LCA foram avaliados pré-cirurgia (24 horas antes da cirurgia) e pós-cirurgia em dois momentos distintos, 4,66 ± 1,03 e 15,83 ± 2,63 meses, respectivamente. As avaliações isocinéticas foram realizadas no modo concêntrico de flexão e extensão do joelho, nas velocidades de 60º/s e 180º/s, em que foram a analisadas as variáveis PT dos isquiotibiais (PTI), PT do quadríceps (PTQ) e a relação entre eles (I/Q). A escala histológica de Mankin modificada foi utilizada para avaliar o grau macroscópico de lesão condral. O teste estatístico ANOVA (p< 0,05) comparou os resultados nos três períodos estudados e o post-hoc teste de Newman Keuls foi utilizado como pós-teste. Posteriormente, foi aplicado o teste de Correlação de Spearman para avaliar a influência do grau de lesão condral com o PT da musculatura da coxa. RESULTADOS: Os resultados mostraram diferenças estatisticamente significativas na relação entre I/Q na velocidade de 60º/s (p= 0,01). O grau de lesão condral variou de 1 a 5, entretanto não houve correlação com os achados isocinéticos. CONCLUSÃO: Identificamos que ocorreu desequilíbrio na relação agonista/antagonista, no que se refere ao torque, entre os grupos musculares do joelho após reconstrução do LCA, entretanto o grau da lesão condral secundária não influenciou o ganho progressivo desse mesmo grupo muscular dentro do período estudado.<br>CONTEXT: The association between anterior cruciate ligament (ACL) injury and the development of secondary osteoarthritis has been the subject of several studies. Ligament injury predisposes joint cartilage lesions, thus influencing motor control and peak torque. OBJECTIVE: To evaluate the influence of the degree of chondral lesion on peak torque of the anterior and posterior musculature of the thigh following ACL injury and reconstruction. METHOD: Six male subjects with total unilateral ACL injury were evaluated 24 hours before surgery and at two times after surgery (4.66 ± 1.03 and 15.83 ± 2.63 months, respectively). Isokinetic evaluations of knee flexion and extension were made in concentric mode, at velocities of 60º/s and 180º/s, and the variables of hamstring peak torque (HPT) and quadriceps peak torque (QPT) and hamstring/quadriceps ratio (H/Q) were analyzed. The modified Mankin histological scale was used to evaluate the macroscopic degree of chondral injury. The ANOVA statistical test (p< 0.05) was used to compare the results between the three times studied, with the Newman-Keuls post-hoc test. Spearman's correlation test was then applied to evaluate the influence of the degree of chondral injury on the peak torque of the thigh musculature. RESULTS: There were statistically significant differences in the H/Q ratio at the velocity of 60º/s (p= 0.01). The degree of chondral injury degree ranged from 1 to 5, although there was no correlation with the isokinetic findings. CONCLUSION: There was an imbalance in agonist/antagonist relationship, with regard to torque, between muscle groups of the knee following ACL reconstruction. However, the degree of secondary chondral lesion did not influence the progressive gains in this muscle groups over the study period