Structural Basis for Recognition of the FLAG-tag by Anti-FLAG M2.

The FLAG-tag/anti-FLAG system is a widely used biochemical tool for protein detection and purification. Anti-FLAG M2 is the most popular antibody against the FLAG-tag, due to its ease of use, versatility, and availability in pure form or as bead conjugate. M2 binds N-terminal, C-terminal and internal FLAG-tags and binding is calcium-independent, but the molecular basis for the FLAG-tag specificity and recognition remains unresolved. Here we present an atomic resolution (1.17 Å) structure of the FLAG peptide in complex with the Fab of anti-FLAG M2, revealing key binding determinants. Five of the eight FLAG peptide residues form direct interactions with paratope residues. The FLAG peptide adopts a 310 helix conformation in complex with the Fab. These structural insights allowed us to rationally introduce point mutations on both the peptide and antibody side. We tested these by surface plasmon resonance, leading us to propose a shorter yet equally binding version of the FLAG-tag for the M2 antibody.

Alternative splicing controls teneurin-3 compact dimer formation for neuronal recognition.

Neuronal network formation is facilitated by recognition between synaptic cell adhesion molecules at the cell surface. Alternative splicing of cell adhesion molecules provides additional specificity in forming neuronal connections. For the teneurin family of cell adhesion molecules, alternative splicing of the EGF-repeats and NHL domain controls synaptic protein-protein interactions. Here we present cryo-EM structures of the compact dimeric ectodomain of two teneurin-3 isoforms that harbour the splice insert in the EGF-repeats. This dimer is stabilised by an EGF8-ABD contact between subunits. Cryo-EM reconstructions of all four splice variants, together with SAXS and negative stain EM, reveal compacted dimers for each, with variant-specific dimeric arrangements. This results in specific trans-cellular interactions, as tested in cell clustering and stripe assays. The compact conformations provide a structural basis for teneurin homo- and heterophilic interactions. Altogether, our findings demonstrate how alternative splicing results in rearrangements of the dimeric subunits, influencing neuronal recognition and likely circuit wiring.

CT respiratory motion synthesis using joint supervised and adversarial learning.

Objective.Four-dimensional computed tomography (4DCT) imaging consists in reconstructing a CT acquisition into multiple phases to track internal organ and tumor motion. It is commonly used in radiotherapy treatment planning to establish planning target volumes. However, 4DCT increases protocol complexity, may not align with patient breathing during treatment, and lead to higher radiation delivery.Approach.In this study, we propose a deep synthesis method to generate pseudo respiratory CT phases from static images for motion-aware treatment planning. The model produces patient-specific deformation vector fields (DVFs) by conditioning synthesis on external patient surface-based estimation, mimicking respiratory monitoring devices. A key methodological contribution is to encourage DVF realism through supervised DVF training while using an adversarial term jointly not only on the warped image but also on the magnitude of the DVF itself. This way, we avoid excessive smoothness typically obtained through deep unsupervised learning, and encourage correlations with the respiratory amplitude.Main results.Performance is evaluated using real 4DCT acquisitions with smaller tumor volumes than previously reported. Results demonstrate for the first time that the generated pseudo-respiratory CT phases can capture organ and tumor motion with similar accuracy to repeated 4DCT scans of the same patient. Mean inter-scans tumor center-of-mass distances and Dice similarity coefficients were 1.97 mm and 0.63, respectively, for real 4DCT phases and 2.35 mm and 0.71 for synthetic phases, and compares favorably to a state-of-the-art technique (RMSim).Significance.This study presents a deep image synthesis method that addresses the limitations of conventional 4DCT by generating pseudo-respiratory CT phases from static images. Although further studies are needed to assess the dosimetric impact of the proposed method, this approach has the potential to reduce radiation exposure in radiotherapy treatment planning while maintaining accurate motion representation. Our training and testing code can be found athttps://github.com/cyiheng/Dynagan.

Erasmus clinical model of the onset and development of stuttering 2.0.

A clinical, evidence-based model to inform clients and their parents about the nature of stuttering is indispensable for the field. In this paper, we propose the Erasmus Clinical Model of Stuttering 2.0 for children who stutter and their parents, and adult clients. It provides an up-to-date, clinical model summary of current insights into the genetic, neurological, motoric, linguistic, sensory, temperamental, psychological and social factors (be it causal, eliciting, or maintaining) related to stuttering. First a review is presented of current insights in these factors, and of six scientific theories or models that have inspired the development of our current clinical model. Following this, we will propose the model, which has proven to be useful in clinical practice. The proposed Erasmus Clinical Model of Stuttering visualizes the onset and course of stuttering, and includes scales for stuttering severity and impact, to be completed by the (parent of) the person who stutters. The pathway of the model towards stuttering onset is based on predisposing and mediating factors. In most children with an onset of stuttering, stuttering is transient, but if stuttering continues, its severity and impact vary widely. The model includes the circle of Engel (1977), which visualizes unique interactions of relevant biological, psychological, and social factors that determine the speaker's experience of stuttering severity and its impact. Discussing these factors and their interaction with an individual client can feed into therapeutic targets. The model is supplemented by a lifeline casus.

Muscle MRI in Patients With Oculopharyngeal Muscular Dystrophy: A Longitudinal Study

BACKGROUND AND OBJECTIVES: Oculopharyngeal muscular dystrophy (OPMD) is a rare progressive neuromuscular disease. MRI is one of the techniques that is used in neuromuscular disorders to evaluate muscle alterations. The aim of this study was to describe the pattern of fatty infiltration of orofacial and leg muscles using quantitative muscle MRI in a large national cohort and to determine whether MRI can be used as an imaging biomarker of disease progression in OPMD. METHODS: Patients with OPMD (18 years or older) were invited from the national neuromuscular database or by their treating physicians and were examined twice with an interval of 20 months, with quantitative MRI of orofacial and leg muscles to assess fatty infiltration which were compared with clinical measures. RESULTS: In 43 patients with genetically confirmed OPMD, the muscles that were affected most severely were the tongue (mean fat fraction: 37.0%, SD 16.6), adductor magnus (31.9%; 27.1), and soleus (27.9%; 21.5) muscles. The rectus femoris and tibialis anterior muscles were least severely affected (mean fat fractions: 6.8%; SD 4.7, 7.5%; 5.9). Eleven of 14 significant correlations were found between fat fraction and a clinical task in the corresponding muscles (r = -0.312 to -0.769, CI = -0.874 to -0.005). At follow-up, fat fractions had increased significantly in 17 of the 26 muscles: mean 1.7% in the upper leg muscles (CI = 0.8-2.4), 1.7% (1.0-2.3) in the lower leg muscles, and 1.9% (0.6-3.3) in the orofacial muscles (p < 0.05). The largest increase was seen for the soleus (3.8%, CI = 2.5-5.1). Correlations were found between disease duration and repeat length vs increased fat fraction in 7 leg muscles (r = 0.323 to -0.412, p < 0.05). DISCUSSION: According to quantitative muscle MRI, the tongue, adductor magnus and soleus show the largest fat infiltration levels in patients with OPMD. Fat fractions increased in several orofacial and leg muscles over 20 months, with the largest fat fraction increase seen in the soleus. This study supports that this technique is sensitive enough to show worsening in fat fractions of orofacial and leg muscles and therefore a responsive biomarker for future clinical trials.

Contactin 2 homophilic adhesion structure and conformational plasticity.

The cell-surface attached glycoprotein contactin 2 is ubiquitously expressed in the nervous system and mediates homotypic cell-cell interactions to organize cell guidance, differentiation, and adhesion. Contactin 2 consists of six Ig and four fibronectin type III domains (FnIII) of which the first four Ig domains form a horseshoe structure important for homodimerization and oligomerization. Here we report the crystal structure of the six-domain contactin 2Ig1-6 and show that the Ig5-Ig6 combination is oriented away from the horseshoe with flexion in interdomain connections. Two distinct dimer states, through Ig1-Ig2 and Ig3-Ig6 interactions, together allow formation of larger oligomers. Combined size exclusion chromatography with multiangle light scattering (SEC-MALS), small-angle X-ray scattering (SAXS) and native MS analysis indicates contactin 2Ig1-6 oligomerizes in a glycan dependent manner. SAXS and negative-stain electron microscopy reveals inherent plasticity of the contactin 2 full-ectodomain. The combination of intermolecular binding sites and ectodomain plasticity explains how contactin 2 can function as a homotypic adhesion molecule in diverse intercellular environments.

Guidelines for the establishment and functioning of Animal Ethics Commitees (Institutional Animal Care and Use Committees) in Africa.

Animals are used for scientific purposes across Africa to benefit humans, animals or the environment. Nonetheless, ethical and regulatory oversight remains limited in many parts of the continent. To strengthen this governance framework, the Pan-African Network for Laboratory Animal Science and Ethics brought together experts from 12 African countries to create an Africa-centric practical guide to facilitate the establishment and appropriate functioning of Institutional Animal Ethics Committees across Africa. The Guidelines are based on universal principles for the care and use of sentient animals for scientific purposes, with consideration of the cultural, religious, political and socio-economic diversity in Africa. They focus on 11 key elements, including responsibilities of institutions and of the Institutional Official; composition of the Committee; its responsibilities, functioning and authority; ethical application and review processes; oversight and monitoring of animal care and use and of training and competence; quality assurance; and the roles of other responsible parties. The intent is for African institutions to adopt and adapt the guidelines, aligning with existing national legislation and standards where relevant, thus ensuring incorporation into practice. More broadly, the Guidelines form an essential component of the growing discourse in Africa regarding moral considerations of, and appropriate standards for, the care and use of animals for scientific purposes. The increased establishment of appropriately functioning animal ethics committees and robust ethical review procedures across Africa will enhance research quality and culture, strengthen societal awareness of animals as sentient beings, improve animal well-being, bolster standards of animal care and use, and contribute to sustainable socio-economic development.

Genomic Diversity and Phenotypic Variation in Fungal Decomposers Involved in Bioremediation of Persistent Organic Pollutants.

Fungi work as decomposers to break down organic carbon, deposit recalcitrant carbon, and transform other elements such as nitrogen. The decomposition of biomass is a key function of wood-decaying basidiomycetes and ascomycetes, which have the potential for the bioremediation of hazardous chemicals present in the environment. Due to their adaptation to different environments, fungal strains have a diverse set of phenotypic traits. This study evaluated 320 basidiomycetes isolates across 74 species for their rate and efficiency of degrading organic dye. We found that dye-decolorization capacity varies among and within species. Among the top rapid dye-decolorizing fungi isolates, we further performed genome-wide gene family analysis and investigated the genomic mechanism for their most capable dye-degradation capacity. Class II peroxidase and DyP-type peroxidase were enriched in the fast-decomposer genomes. Gene families including lignin decomposition genes, reduction-oxidation genes, hydrophobin, and secreted peptidases were expanded in the fast-decomposer species. This work provides new insights into persistent organic pollutant removal by fungal isolates at both phenotypic and genotypic levels.

Online monitoring of focal spasticity treatment with botulinum toxin in people with chronic stroke or hereditary spastic paraplegia: a feasibility study.

OBJECTIVE: To investigate the feasibility and usability of an online spasticity monitoring tool amongst people with hereditary spastic paraplegia or chronic stroke receiving botulinum toxin treatment, and their healthcare providers. METHODS: Mixed methods cohort study, measuring recruitment success and adherence to the monitoring in 3 rehabilitation institutions. In addition, the System Usability Scale (SUS) and interviews with patients and their healthcare providers were used for quantitative and qualitative analysis, respectively. A deductive directed content analysis was used for qualitative evaluation. RESULTS: Of the 19 persons with hereditary spastic paraplegia and 24 with stroke who enrolled in the study, recruitment success and adherence were higher amongst people with hereditary spastic paraplegia compared with stroke. Usability was found "marginal" by rehabilitation physicians and "good" by patients and physical therapists (SUS scores 69, 76, and 83, respectively). According to all participant groups, online monitoring potentially contributes to spasticity management if it is tailored to the actual needs and capabilities of patients, and if it can easily be integrated into the daily/working routines of all users. CONCLUSION: Online monitoring of spasticity in people with hereditary spastic paraplegia or stroke receiving treatment with botulinum toxin may be feasible, provided that the monitoring tool is tailored to the needs of all users.

Nanoplastics causes extensive congenital malformations during embryonic development by passively targeting neural crest cells.

Nanomaterials are widespread in the human environment as pollutants, and are being actively developed for use in human medicine. We have investigated how the size and dose of polystyrene nanoparticles affects malformations in chicken embryos, and have characterized the mechanisms by which they interfere with normal development. We find that nanoplastics can cross the embryonic gut wall. When injected into the vitelline vein, nanoplastics become distributed in the circulation to multiple organs. We find that the exposure of embryos to polystyrene nanoparticles produces malformations that are far more serious and extensive than has been previously reported. These malformations include major congenital heart defects that impair cardiac function. We show that the mechanism of toxicity is the selective binding of polystyrene nanoplastics nanoparticles to neural crest cells, leading to the death and impaired migration of those cells. Consistent with our new model, most of the malformations seen in this study are in organs that depend for their normal development on neural crest cells. These results are a matter of concern given the large and growing burden of nanoplastics in the environment. Our findings suggest that nanoplastics may pose a health risk to the developing embryo.

Using the Generic Analysis Method to Analyze Sentinel Event Reports Across Hospitals: A Retrospective Cross-Sectional Study.

OBJECTIVES: Improving patient safety by investigating sentinel events (SEs) is hampered by the focus on isolated events within hospitals and a narrow scope of traditional root cause analysis methods. We aimed to examine if performing cross-hospital aggregate analysis of SEs applying a novel generic analysis method (GAM) bearing a human factor perspective can enhance learning from SEs. METHODS: A retrospective cross-sectional review of SE reports from 28 Dutch general hospitals using the GAM to reanalyze events was performed. A qualitative approach was used to identify contributing factors and system issues. Findings were discussed with a patient safety expert panel. Descriptive statistics and measures of associations between domains were calculated. RESULTS: Sixty-nine SE reports were reviewed. Applying the GAM provided a more holistic SE analysis than a traditional method. Of the 405 identified contributing factors in all SEs, the majority was related to the persons involved (patients and professionals, n = 146 [36.2%]) and the organization (n = 121 [30%]). The most frequently recurring pattern was the combination of factors related to the persons involved, the technology used, the tasks of professionals, and organizational factors influencing the event. Cross-hospital aggregate GAM analysis of SEs helped to identify system issues and propose more system-oriented overarching recommendations. CONCLUSIONS: This study found that applying the GAM to analyze SEs across hospitals can help to improve learning from SEs and may result in proposing stronger recommendations. The method can support hospitals, working together in a network of hospitals, to jointly learn from SEs.

Clinimetric Evaluation of the Experienced Communication in Dementia Questionnaire.

BACKGROUND AND OBJECTIVES: Tools to measure self-perceived communication between persons with early-stage dementia and their caregivers are lacking. Therefore, we developed a questionnaire for Experienced Communication in Dementia (ECD) with a patient version (ECD-P) and a caregiver version (ECD-C), which contains items on (a) caregiver competence, (b) social communication, (c) communication difficulties, and (d) experienced emotions. This article describes the feasibility and clinimetric evaluation of this instrument. RESEARCH DESIGN AND METHODS: A prospective observational cohort study was conducted with 57 dyads (community-dwelling person with dementia and primary caregiver). ECD-P, ECD-C, and measures on quality of life, caregiver burden, cognitive functioning, physical functioning, and functional independence were administered. After 2 weeks, the dyads filled out the ECD again. Feasibility (completion time and missing values per item), internal consistency (Cronbach's α), test-retest reliability (intraclass correlation coefficients [ICCs]), and construct validity (hypotheses testing with Spearman's r) were evaluated. RESULTS: Mean completion time was 10 min per questionnaire. ICCs for test-retest reliability ranged from 0.67 to 0.78, except for ECD-P2 (ICC = 0.31). Internal consistency ranged from α = 0.75 to 0.82 for ECD-P1 and all parts of ECD-C, except for ECD-P2 (α = 0.66). Correlation coefficients for convergent validity ranged from r = 0.31 to 0.69 and correlation coefficients for divergent validity were r < 0.20 and statistically insignificant. DISCUSSION AND IMPLICATIONS: Pending future research, the ECD, except part ECD-P2, seems to be a promising tool to measure experienced communication between persons with early-stage dementia and their caregivers.

A large family with MSH3-related polyposis.

Biallelic MSH3 germline variants are a rare cause of adenomatous polyposis as yet reported in two small families only. We describe the phenotype of a third family, the largest thus far, with adenomatous polyposis related to compound heterozygous MSH3 pathogenic variants. The index patient was a 55-years old male diagnosed with rectal cancer and adenomatous polyposis (cumulatively 52 polyps), with a family history of colorectal polyposis with unknown cause. Next-generation sequencing and copy number variation analysis of a panel of genes associated with colorectal cancer and polyposis revealed compound heterozygous germline pathogenic variants in the MSH3 gene. Nine out of 11 siblings were genotyped. Three siblings carried the same compound heterozygous MSH3 variants. Colonoscopy screening showed predominantly right-sided adenomatous polyposis in all compound heterozygous siblings, with a cumulative number of adenomas ranging from 18 to 54 in an average of four colonoscopies, and age at first adenoma detection ranging from 46 to 59. Microsatellite analysis demonstrated alterations at selected tetranucleotide repeats (EMAST) in DNA retrieved from the rectal adenocarcinoma, colorectal adenomas as well as of normal colonic mucosa. Gastro-duodenoscopy did not reveal adenomas in any of the four patients. Extra-intestinal findings included a ductal adenocarcinoma in ectopic breast tissue in one female sibling at the age of 46, and liver cysts in three affected siblings. None of the three heterozygous or wild type siblings who previously underwent colonoscopy had adenomatous polyposis. We conclude that biallelic variants in MSH3 are a rare cause of attenuated adenomatous polyposis with an onset in middle age.

Com-mens: a home-based logopaedic intervention program for communication problems between people with dementia and their caregivers - a single-group mixed-methods pilot study.

BACKGROUND: Communication difficulties are common in people with dementia, and often present from an early stage. However, direct treatment options for people with dementia that positively influence their daily communication are scarce. AIMS: To evaluate the potential impact and feasibility of a personalized logopaedic intervention. METHODS & PROCEDURES: A total of 40 community-dwelling persons with dementia and their caregivers were recruited. Five experienced speech and language therapists (SLTs) delivered the six-session Com-mens intervention at home. Com-mens aims to improve positive communication between people with dementia and their primary caregivers and comprises five elements: interactive history-taking, dynamic observational assessment, education about the consequences of dementia on communication, development and use of personalized communication tools, use motivational, and person-centred strategies by the SLT. We conducted a single-group mixed-methods pilot study with five measurements: baseline, directly after intervention, and at 3, 6 and 9 months follow-up. Semi-structured interviews and questionnaires for Experienced Communication in Dementia, quality of life, psychological well-being and caregiver burden were conducted. Process evaluation was performed by interviewing participants, drop-outs, SLTs and other stakeholders. OUTCOMES & RESULTS: A total of 32 dyads completed the intervention. Repeated measures analyses revealed no significant changes over time. In the interviews, participants reported a positive impact on their feelings, increased communication skills and better coping with the diagnosis. Participants would recommend the intervention to others. Facilitators were timely delivery, personalized content and adequate reimbursement. Barriers were unfamiliarity with Com-mens among referrers, an overburdened caregiver or disrupted family relationships. CONCLUSIONS & IMPLICATIONS: This newly developed logopaedic intervention is feasible and has a perceived positive impact on both people with dementia and their caregivers, which is confirmed by a stable pattern over a period of 1 year. Future comparative studies are needed to test the effectiveness of personalized interventions in this patient population. WHAT THIS PAPER ADDS: What is already known on the subject? SLTs are experts in the field of communication, but even though communication problems are common between people with dementia and their caregivers, there is a lack of logopaedic guidelines and materials for the direct treatment for this population. Interventions that are available either focus on (professional) caregivers only or aim to enhance cognitive functioning and do not target on joined communication. What this paper adds to the existing knowledge? A newly developed intervention called Com-mens can be provided by trained SLTs and takes an average of six 1-h sessions. The intervention is perceived to be valuable and feasible for people with dementia and their caregivers, by the participants themselves, as well as by healthcare professionals and other stakeholders. What are the potential or actual clinical implications of this work? Dissemination of this intervention will give SLTs skills, tools and materials to provide meaningful care to home-dwelling persons with dementia and their caregivers. Also, persons with dementia and their caregivers will receive education and materials that can help them increase their understanding of communication problems, enhance their communication skills and better cope with the communication problems that result from dementia. We consider the Com-mens intervention to be a valuable addition to the field of speech language therapy and dementia.

Sustainable education and training in laboratory animal science and ethics in low- and middle-income countries in Africa - challenges, successes, and the way forward.

Despite the recognised need for education and training in laboratory animal science (LAS) and ethics in Africa, access to such opportunities has historically been limited. To address this, the Pan-African Network for Laboratory Animal Science and Ethics (PAN-LASE) was established to pioneer a support network for the development of education and training in LAS and ethics across the African continent.In the 4.5 years since the establishment of PAN-LASE, 3635 individuals from 28 African countries have participated in our educational activities. Returning to their home institutions, they have both established and strengthened institutional and regional hubs of knowledge and competence across the continent. Additionally, PAN-LASE supported the development of guidelines for establishment of institutional Animal Ethics Committees, a critical step in the implementation of ethical review processes across the continent, and in enhancing animal welfare and scientific research standards.Key challenges and opportunities for PAN-LASE going forward include the formalisation of the network; the sustainability of education and training programmes; implementation of effective hub-and-spoke models of educational provision; strengthening governance frameworks at institutional, national and regional levels; and the availability of Africa-centric open access educational resources.Our activities are enhancing animal welfare and the quality of animal research undertaken across Africa, enabling African researchers to undertake world-leading research to offer solutions to the challenges facing the continent. The challenges, successes and the lessons learnt from PAN-LASE's journey are applicable to other low- and middle-income countries across the world seeking to enhance animal welfare, research ethics and ethical review in their own country or region.

Structural insights into the contactin 1 - neurofascin 155 adhesion complex.

Cell-surface expressed contactin 1 and neurofascin 155 control wiring of the nervous system and interact across cells to form and maintain paranodal myelin-axon junctions. The molecular mechanism of contactin 1 - neurofascin 155 adhesion complex formation is unresolved. Crystallographic structures of complexed and individual contactin 1 and neurofascin 155 binding regions presented here, provide a rich picture of how competing and complementary interfaces, post-translational glycosylation, splice differences and structural plasticity enable formation of diverse adhesion sites. Structural, biophysical, and cell-clustering analysis reveal how conserved Ig1-2 interfaces form competing heterophilic contactin 1 - neurofascin 155 and homophilic neurofascin 155 complexes whereas contactin 1 forms low-affinity clusters through interfaces on Ig3-6. The structures explain how the heterophilic Ig1-Ig4 horseshoe's in the contactin 1 - neurofascin 155 complex define the 7.4 nm paranodal spacing and how the remaining six domains enable bridging of distinct intercellular distances.

Enhancing the role of the social network in activity (re)engagement post-stroke: a focus group study with rehabilitation professionals.

BACKGROUND: People post-stroke are at risk of not being able to participate in valued activities. It is important that rehabilitation professionals prepare people post-stroke for the transition home and provide needed support when they live at home. Several authors have suggested that members of the broad social network should play an active role in rehabilitation. This includes informing them about the importance of activity (re)engagement post-stroke and learning strategies to provide support. It is not clear when and how the broad social network can best be equipped to provide adequate activity support. This study aimed to explore stroke professionals' perspectives on strategies that establish a social network that supports activity (re)engagement of people post-stroke, when strategies are best implemented, and the factors that influence the implementation of these strategies. METHODS: Two focus groups were executed. Content analysis was used to analyze the transcripts of the recorded conversations. RESULTS: Eighteen professionals with various professional backgrounds and roles in treating people post-stroke participated. Strategies to establish a supportive social network included identifying, expanding, informing, and actively engaging network members. Working with the network in the immediate post-stroke phase was regarded as important for improving long-term activity outcomes. Participants expressed that most strategies to equip the social network to support people post-stroke need to take place within community care. However, the participants experienced difficulties in implementing network strategies. Perceived barriers included interprofessional collaboration, professional knowledge, self-efficacy, and financial structures. CONCLUSIONS: Strategies to involve the social network of people post-stroke are not fully implemented. Although identifying members of a social network should begin during inpatient rehabilitation, the main part of actively engaging the network will have to take place when the people post-stroke return home. Implementing social network strategies requires a systematic process focusing on collaboration, knowledge, attitude, and skill development.

A desiccation compound as a biofilm- and necrosis-removing agent: a case series.

OBJECTIVE: A new compound, Debrichem (DEBx Medical BV, the Netherlands), a topical desiccation agent (TDA), is an active gel that contains an acidic species with a potent hygroscopic action. When in contact with microorganisms and necrosis, rapid desiccation and carbonisation of the proteins in these microorganisms, as well as of the extracellular matrix of biofilms and necrosis, occurs. The resulting 'precipitate' rapidly dislodges from the wound bed, resulting in a clean wound which granulates, which is a prerequisite for healing by secondary intention. METHOD: In a retrospective study, a series of mostly large and hard-to-heal lesions of different aetiologies were treated with a one-time application of the TDA, followed by weekly dressing changes. RESULTS: Of the total of 54 lesions included in this case series, 22 were diagnosed as venous leg ulcers (VLUs), 20 as diabetic foot ulcers (DFUs), nine as post-traumatic, hard-to-heal lesions, two as vascular ulcers and one as an ischaemic ulcer. All of the VLUs, 75% of the DFUs and all of the other lesions reached complete granulation. CONCLUSION: The use of a TDA may contribute to the consistent, fast and easy removal of both biofilms and necrosis, and hence to wound healing.

Muscle ultrasound is a sensitive biomarker in oculopharyngeal muscular dystrophy.

INTRODUCTION/AIMS: Oculopharyngeal muscular dystrophy (OPMD) is a late-onset, progressive muscle disease. Quantitative muscle ultrasound (QMUS) assesses structural changes in muscles and is a sensitive biomarker in neuromuscular disorders. Our aim of this study was to determine whether QMUS can detect muscle pathology and can be used as longitudinal imaging biomarker in OPMD. METHODS: Genetically confirmed OPMD patients, recruited by their treating physicians or from the national neuromuscular database, were examined twice, 20 months apart, using QMUS of orofacial and limb muscles, and measurements of functional capacity and muscle strength. Absolute echo intensity (AEI) and muscle thickness of all muscles were analyzed and correlated with clinical data. RESULTS: The tongue, deltoid, iliopsoas, rectus femoris, and soleus muscles showed increased AEI at baseline compared with normal values in 43 OPMD patients, with the rectus femoris being most often affected (51%).The AEI and muscle thickness of 9 of 11 muscles correlated significantly with the motor function measure, 10-step stair test, swallowing capacity, dynamometry, Medical Research Council grade, tongue strength, and bite force (r = 0.302 to -0.711). Between baseline and follow-up, deterioration in AEI was found for the temporalis, tongue, and deltoid muscles, and decreased muscle thickness was detected for the temporalis, masseter, digastric, tongue, deltoid, iliopsoas, and soleus muscles (P < .05). No relation was found between the change in AEI and repeat length or disease duration. DISCUSSION: QMUS detected muscle pathology and disease progression in OPMD over 20 months. We conclude that QMUS should be considered as a biomarker in treatment trials.

Mechanistic insights into the C55-P targeting lipopeptide antibiotics revealed by structure-activity studies and high-resolution crystal structures.

The continued rise of antibiotic resistance is a global concern that threatens to undermine many aspects of modern medical practice. Key to addressing this threat is the discovery and development of new antibiotics that operate by unexploited modes of action. The so-called calcium-dependent lipopeptide antibiotics (CDAs) are an important emerging class of natural products that provides a source of new antibiotic agents rich in structural and mechanistic diversity. Notable in this regard is the subset of CDAs comprising the laspartomycins and amphomycins/friulimicins that specifically target the bacterial cell wall precursor undecaprenyl phosphate (C55-P). In this study we describe the design and synthesis of new C55-P-targeting CDAs with structural features drawn from both the laspartomycin and amphomycin/friulimicin classes. Assessment of these lipopeptides revealed previously unknown and surprisingly subtle structural features that are required for antibacterial activity. High-resolution crystal structures further indicate that the amphomycin/friulimicin-like lipopeptides adopt a unique crystal packing that governs their interaction with C55-P and provides an explanation for their antibacterial effect. In addition, live-cell microscopy studies provide further insights into the biological activity of the C55-P targeting CDAs highlighting their unique mechanism of action relative to the clinically used CDA daptomycin.