Reconsidering assumptions in the analysis of muscle fibre cross-sectional area.

Cross-sectional area (CSA) is a fundamental variable in characterizing muscle mechanical properties. Typically, the CSA of a single muscle fibre is assessed by measuring either one or two diameters, and assuming the cross-section is either circular or elliptical in shape. However, fibre cross-sections have irregular shapes.

Direct and indirect costs of idiopathic inflammatory myopathies in adults: A systematic review.

Idiopathic inflammatory myopathies (IIMs) are rare disorders characterized by inflammation of skeletal muscle, which can result in fatty replacement of muscle, muscle atrophy, and subsequent weakness. Therapeutic advancements have improved clinical outcomes but impose an economic impact on healthcare systems. We aimed to summarize the direct and indirect costs associated with IIMs in a systematic review (PROSPERO Registration #CRD42023443143).

Qualitative Analysis of Initial Palliative Care Consultations in Amyotrophic Lateral Sclerosis.

Background: Palliative care (PC) benefits patients with amyotrophic lateral sclerosis (ALS), however the needs of patients and caregivers and the optimal timing of PC discussions remains unclear. This study reports the analysis of PC consult notes from a larger feasibility trial. The specific aims of this analysis were to i) identify the PC needs of patients with ALS via qualitative analysis and ii) identify characteristics of patients and caregivers that could predict specific PC needs.

Congenital tremor and myopathy secondary to novel MYBPC1 variant.

Congenital myopathy with tremor (MYOTREM) is a recently described disorder characterized by mild myopathy and a postural and intention tremor present since early infancy. MYOTREM is associated with pathogenic variants in MYBPC1 which encodes slow myosin-binding protein C, a sarcomere protein with regulatory and structural roles. Here, we describe a family with three generations of variably affected members exhibiting a novel variant in MYBPC1 (c.

Emerging and established biomarkers of oculopharyngeal muscular dystrophy.

Oculopharyngeal muscular dystrophy (OPMD) is a rare, primarily autosomal dominant, late onset muscular dystrophy commonly presenting with ptosis, dysphagia, and subsequent weakness of proximal muscles. Although OPMD diagnosis can be confirmed with high confidence by genetic testing, the slow progression of OPMD poses a significant challenge to clinical monitoring and a barrier to assessing the efficacy of treatments during clinical trials. Accordingly, there is a pressing need for more sensitive measures of OPMD progression, particularly those which do not require a muscle biopsy.

Palliative care at any stage of amyotrophic lateral sclerosis: a prospective feasibility study.

Introduction: Many patients with amyotrophic lateral sclerosis (ALS) receive palliative care (PC) very late or not at all. The impact of PC on patients with ALS and caregivers has not been quantified. Study goals included (1) measuring the impact of early PC on quality of life and mood of patients/caregivers and (2) describing patient/caregiver satisfaction with PC.

Assumptions about the cross-sectional shape of skinned muscle fibers can distort the relationship between muscle force and cross-sectional area.

Comparisons of muscle force output are often performed after normalization to muscle physiological cross-sectional area (CSA). Differences in force per CSA (i.e.

Novel Homozygous Variant in in Siblings With Hereditary Motor Neuropathy.

Background And Objectives: Coenzyme Q (CoQ) is an important electron carrier and antioxidant. The COQ7 enzyme catalyzes the hydroxylation of 5-demethoxyubiquinone-10 (DMQ), the second-to-last step in the CoQ biosynthesis pathway. We report a consanguineous family presenting with a hereditary motor neuropathy associated with a homozygous c.

Case Report: Severe Peripartum Cardiac Disease in Myotonic Dystrophy Type 1.

Background: Myotonic dystrophy type 1 (DM1) is a hereditary muscular dystrophy affecting ∼2.1-14.3/100,000 adults.

Effect of Active Lengthening and Shortening on Small-Angle X-ray Reflections in Skinned Skeletal Muscle Fibres.

Our purpose was to use small-angle X-ray diffraction to investigate the structural changes within sarcomeres at steady-state isometric contraction following active lengthening and shortening, compared to purely isometric contractions performed at the same final lengths. We examined force, stiffness, and the 1,0 and 1,1 equatorial and M3 and M6 meridional reflections in skinned rabbit psoas bundles, at steady-state isometric contraction following active lengthening to a sarcomere length of 3.0 µm (15.

Contractility of permeabilized rat vastus intermedius muscle fibres following high-fat, high-sucrose diet consumption.

Obesity is a worldwide health concern associated with impaired physical function. It is not clear if contractile protein dysfunction contributes to the impairment of muscle function observed with obesity. The purpose of this study was to examine if diet-induced obesity affects contractile function of chemically permeabilized vastus intermedius fibres of male Sprague-Dawley rats expressing fast myosin heavy chain (MHC) IIa or slow MHC I.

The experiences of therapists providing psychological treatment for adults with depression and intellectual disabilities as part of a randomised controlled trial.

Background: Health professionals were trained to deliver adapted psychological interventions for depression to people with learning disabilities and depression alongside a supporter. Exploring the delivery of psychological interventions can help increase access to therapy.

Method: Twenty-seven participants took part in six focus groups, and the data were subject to a Framework Analysis.

Contractile history affects sag and boost properties of unfused tetanic contractions in human quadriceps muscles.

Purpose: A period of extra-efficient force production ("boost") followed by a decline in force ("sag") is often observed at the onset of unfused tetanic contractions. We tested the hypothesis that in human muscle boost and sag are diminished in repeated contractions separated by short rest periods and are re-established or enhanced following long rest periods.

Methods: Two sets of 3 unfused tetanic contractions were evoked in the right quadriceps muscle group of 29 participants via percutaneous stimulation of the femoral nerve.

The effects of inorganic phosphate on contractile function of slow skeletal muscle fibres are length-dependent.

Muscle operates across a wide range of sarcomere lengths. Inorganic phosphate (P) diminishes force output of striated muscle, with greater influence at short relative to long sarcomere lengths in fast skeletal and cardiac muscle fibres. The purpose of this study was to fill a gap in the literature regarding the length-dependent effects of P on contractile function of slow skeletal muscle fibres.

Abemaciclib Combined With Endocrine Therapy for the Adjuvant Treatment of HR+, HER2-, Node-Positive, High-Risk, Early Breast Cancer (monarchE).

Purpose: Many patients with HR+, HER2- early breast cancer (EBC) will not experience recurrence or have distant recurrence with currently available standard therapies. However, up to 30% of patients with high-risk clinical and/or pathologic features may experience distant recurrence, many in the first few years. Superior treatment options are needed to prevent early recurrence and development of metastases for this group of patients.

Initial force production before sag is enhanced by prior contraction followed by a 3-minute rest period in fast motor units of the rat medial gastrocnemius.

Unfused tetanic contractions evoked in fast motor units exhibit extra-efficient force production at the onset of contraction, an effect called "boost". Boost is diminished in subsequent contractions if there is a short rest period between contractions, but can be re-established with a longer period of rest. We tested the hypothesis that contractile activity and rest could enhance boost-related metrics.

A brief contraction has complex effects on summation of twitch pairs in human adductor pollicis.

New Findings: What is the central question of this study? How do contraction-induced reductions in twitch duration, without changes in twitch force, affect summation of twitch pairs into higher force contractions in skeletal muscle? What is the main finding and its importance? Abbreviating twitch duration with a brief contraction resulted in enhanced summation of fully fused twitch pairs, but impaired summation in partially fused twitch pairs even after accounting for the differences in relaxation of the first twitch. An inherent mechanism which enhances relaxation without sacrificing force generation in forceful contractions would benefit cyclic muscle activities, such as locomotion.

Abstract: During electrically evoked contractions of skeletal muscle, the interplay between twitch duration and the time between electrical stimuli (inter-pulse interval, IPI) determines how effectively twitch forces summate into high force contractions.

How service-users with intellectual disabilities understand challenging behaviour and approaches to managing it.

Background: This study explored understandings that service-users with intellectual disabilities and challenging behaviour held around their behaviour, what shaped these understandings, and the relationship between how behaviours are managed and well-being.

Methods: Eight participants (three female, five male) partook in individual semi-structured qualitative interviews. Interviews were transcribed and analysed using interpretative phenomenological analysis.

Adapting dialectical behaviour therapy in forensic learning disability services: A grounded theory informed study of "what works".

Background: Emerging evidence indicates effectiveness of dialectical behaviour therapy (DBT) for people with intellectual disabilities (PWID) in forensic settings; however, little is known about "what works" facilitating engagement and change.

Methods: Eleven interviews were conducted with nine service users across two secure inpatient services. Grounded theory was used to develop a model of perceived engagement and change.

Caffeine attenuates contraction-induced diminutions of the intracellular calcium transient in mouse lumbrical muscle ex vivo.

The amount of calcium released from the sarcoplasmic reticulum in skeletal muscle rapidly declines during repeated twitch contractions. In this study, we test the hypothesis that caffeine can mitigate these contraction-induced declines in calcium release. Lumbrical muscles were isolated from male C57BL/6 mice and loaded with the calcium-sensitive indicator, AM-furaptra.

Prognostic characteristics in hormone receptor-positive advanced breast cancer and characterization of abemaciclib efficacy.

CDK4 & 6 inhibitors have enhanced the effectiveness of endocrine therapy (ET) in patients with advanced breast cancer (ABC). This paper presents exploratory analyses examining patient and disease characteristics that may inform in whom and when abemaciclib should be initiated. MONARCH 2 and 3 enrolled women with HR+, HER2- ABC.

Acoustic phonon lifetimes limit thermal transport in methylammonium lead iodide.

Hybrid organic-inorganic perovskites (HOIPs) have become an important class of semiconductors for solar cells and other optoelectronic applications. Electron-phonon coupling plays a critical role in all optoelectronic devices, and although the lattice dynamics and phonon frequencies of HOIPs have been well studied, little attention has been given to phonon lifetimes. We report high-precision momentum-resolved measurements of acoustic phonon lifetimes in the hybrid perovskite methylammonium lead iodide (MAPI), using inelastic neutron spectroscopy to provide high-energy resolution and fully deuterated single crystals to reduce incoherent scattering from hydrogen.