Muscle activation during gait in children with Duchenne muscular dystrophy

The aim of this prospective study was to investigate changes in muscle activity during gait in children with Duchenne muscular Dystrophy (DMD). Dynamic surface electromyography recordings (EMGs) of 16 children with DMD and pathological gait were compared with those of 15 control children. The activity of the rectus femoris (RF), vastus lateralis (VL), medial hamstrings (HS), tibialis anterior (TA) and gastrocnemius soleus (GAS) muscles was recorded and analysed quantitatively and qualitatively. The overall muscle activity in the children with DMD was significantly different from that of the control group. Percentage activation amplitudes of RF, HS and TA were greater throughout the gait cycle in the children with DMD and the timing of GAS activity differed from the control children. Significantly greater muscle coactivation was found in the children with DMD. There were no significant differences between sides. Since the motor command is normal in DMD, the hyper-activity and co-contractions likely compensate for gait instability and muscle weakness, however may have negative consequences on the muscles and may increase the energy cost of gait. Simple rehabilitative strategies such as targeted physical therapies may improve stability and thus the pattern of muscle activity

PReS-FINAL-2232: Long-term follow-up in a national cohort of MKD patients: search for clinical predictors of a spontaneous improvement

No abstract availabl

Histone-Specific CD4+ T Cell Plasticity in Active and Quiescent Systemic Lupus Erythematosus

Objective: The aim of this study was to assess whether circulating histone-specific T cells represent tools for precision medicine in systemic lupus erythematosus (SLE). Methods: Seroprevalence of autoantibodies and HLA-DR beta (DRB) 1 profile were assessed among 185 patients with SLE and combined with bioinformatics and literature evidence to identify HLA–peptide autoepitope couples for ex vivo detection of antigen-specific T cells through flow cytometry. T cell differentiation and polarization was investigated in patients with SLE, patients with Takayasu arteritis, and healthy controls carrying HLA-DRB1*03:01 and/or HLA-DRB1*11:01. SLE Disease Activity Index 2000 and Lupus Low Disease Activity State were used to estimate disease activity and remission. Results: Histone-specific CD4+ T cells were selectively detected in patients with SLE. Among patients with a history of anti-DNA antibodies, 77% had detectable histone-specific T cells, whereas 50% had lymphocytes releasing cytokines or upregulating activation markers after in vitro challenge with histone peptide antigens. Histone-specific regulatory and effector T helper (Th) 1-, Th2-, and atypical Th1/Th17 (Th1*)-polarized cells were significantly more abundant in patients with SLE with quiescent disease. In contrast, total Th1-, Th2-, and Th1*-polarized and regulatory T cells were similarly represented between patients and controls or patients with SLE with active versus quiescent disease. Histone-specific effector memory T cells accumulated in the blood of patients with quiescent SLE, whereas total effector memory T cell counts did not change. Immunosuppressants were associated with expanded CD4+ histone-specific naive T (TN) and terminally differentiated T cells. Conclusion: Histone-specific T cells are selectively detected in patients with SLE, and their concentration in the blood varies with disease activity, suggesting that they represent innovative tools for patient stratification and therapy. (Figure presented.)

Translational implications of Th17-skewed inflammation due to genetic deficiency of a cadherin stress sensor

Desmoglein 1 (Dsg1) is a cadherin restricted to stratified tissues of terrestrial vertebrates, which serve as essential physical and immune barriers. Dsg1 loss-of-function mutations in humans result in skin lesions and multiple allergies, and isolated patient keratinocytes exhibit increased proallergic cytokine expression. However, the mechanism by which genetic deficiency of Dsg1 causes chronic inflammation is unknown. To determine the systemic response to Dsg1 loss, we deleted the 3 tandem Dsg1 genes in mice. Whole transcriptome analysis of embryonic Dsg1–/– skin showed a delay in expression of adhesion/differentiation/ keratinization genes at E17.5, a subset of which recovered or increased by E18.5. Comparing epidermal transcriptomes from Dsg1-deficient mice and humans revealed a shared IL-17–skewed inflammatory signature. Although the impaired intercellular adhesion observed in Dsg1–/– mice resembles that resulting from anti-Dsg1 pemphigus foliaceus antibodies, pemphigus skin lesions exhibit a weaker IL-17 signature. Consistent with the clinical importance of these findings, treatment of 2 Dsg1-deficient patients with an IL-12/IL-23 antagonist originally developed for psoriasis resulted in improvement of skin lesions. Thus, beyond impairing the physical barrier, loss of Dsg1 function through gene mutation results in a psoriatic-like inflammatory signature before birth, and treatment with a targeted therapy significantly improved skin lesions in patients

Compensatory movements during functional activities in ambulatory children with Duchenne muscular dystrophy

Objective: During the transitional phase (ambulatory to non-ambulatory), synergies characterize the evolution of Duchenne muscular dystrophy (DMD). This study was performed to describe and quantify compensatory movements while sitting down on/rising from the floor and climbing up/down steps. Method: Eighty videos (5 children × 4 assessments × 4 tasks) were recorded quarterly in the year prior to gait loss. Compensatory movements from the videos were registered based on the Functional Evaluation Scale for DMD. Results: The most frequently observed compensatory movements were upper limb support on lower limbs/floor/handrail during all the tasks and lumbar hyperlordosis, trunk support on handrail, equinus foot, increased base of support, non-alternated descent, and pauses while climbing up/down steps. Conclusion: Climbing up/down steps showed a higher number of compensatory movements than sitting down on/rising from the floor, which seemed to be lost before climbing up/down steps in ambulatory children with DMD

Osteological peculiarities of Bufo brongersmai (Anura: Bufonidae) and their possible relation to life in an arid environment

Osteological peculiarities of Bufo brongersmai (Anura: Bufonidae) and their possible relation to life in an arid environment. Zoological Studies 48(1): 108-119. The morphology of selected isolated skeletal elements of the northwestern African endemic toad Bufo brongersmai Hoogmoed 1972 is herein described and compared to those of other Bufo species inhabiting the same area and Europe. The osteological morphology of this species clearly differentiates it from others within the genus, and several diagnostic osteological characters are added to the specific diagnosis. In particular, the presence in adult individuals of a rather-large maxillary fontanella, which late in ontogeny is reduced to a few foramina, has not been observed in other species. These fontanellae, as well as the fenestrations on the sphenethmoid, together with other osteological traits, suggest a significant degree of hypo-ossification. This seems likely related to the rapid larval development that allows B. brongersmai to achieve higher reproductive fitness than other species in the highly ephemeral waters of the rocky, arid environment it inhabits. Other peculiar osteological traits could be related to the exploitation of small crevices to protect adults from overheating and desiccation