370 research outputs found

    Shoulder joint replacement can improve quality of life and outcome in patients with dysmelia: a case series

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    Background: Arthroplasty is a proven treatment option for glenohumeral osteoarthritis. Common indications include primary or posttraumatic osteoarthritis, avascular necrosis of the humeral head, rotator cuff tear arthropathy and rheumatoid osteoarthritis. Arthroplasty is rarely performed among patients with glenohumeral dysmelia. An overuse of the upper limb in patients with thalidomide-induced phocomelia and people with similar congenital deformities like dysmelia results in premature wear of the shoulder joint. This study aims to evaluate our experience with cases of glenohumeral osteoarthritis caused by dysmelia and treated with arthroplasty. To date, few reports on the outcome of shoulder arthroplasty exist on this particular patient group. Case presentation: We included four dysmelic patients (five shoulders) with substantial glenoid dysplasia in a prospective database after approval by the local ethics committee. Once conservative treatment options had been exhausted, the patients were treated with shoulder arthroplasty and assessed clinically and radiographically before and after surgery. The mean patient age at the time of surgery was 50.4 years. The minimum follow-up time was 24 months (24–91 months). All patients experienced a considerable improvement of range of motion (ROM) and a relief of pain. No intra- or postoperative complications appeared. Conclusion: Patients with dysmelia have acceptable short and mid-term results with resurfacing hemiarthroplasty. It is an effective although somewhat complicated method to relieve pain and improve movement. Long-term performance of arthroplasty in patients with dysmelia remains to be seen, particularly with regard to the remaining problem of the altered and often deficient glenoid

    50 Hz X‐Ray Diffraction Stress Analysis and Numerical Process Simulation at Laser Surface Line Hardening of Web Structures

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    In situ synchrotron X-ray diffraction experiments were carried out during laser surface line hardening of the common tempering steel AISI 4140 at beamline P05@PETRA III operated by Helmholtz-Zentrum Geesthacht at the Deutsches Elektronen Synchrotron, Hamburg, Germany. A unique process chamber was used to investigate the phase and transverse surface stress evolution during a laser line hardening processes. Synchrotron radiation, in combination with microstrip line detectors, allows for a time resolution of 50 Hz. Specimen geometries were hardened using a high-power diode laser under control of the surface temperature and constant laser beam feed. Herein, it is focused on web-structured specimens in contrast to a flat geometry. The experimental results are discussed with regard to the workpiece geometry effect of the web structure dimensions on the temporal and spatial stress evolution. In addition, numerical process simulations based on the finite element method were carried out to support the drawn conclusions. The presented model is able to predict the surface transverse stresses inside the process zone center, while providing further 3D information. A heat build-up in the web leads to a wider and deeper process zone, however, the absolute hardness increase and the transverse residual stresses at the surface center are not affected

    Opportunities and challenges for digital morphology

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    Advances in digital data acquisition, analysis, and storage have revolutionized the work in many biological disciplines such as genomics, molecular phylogenetics, and structural biology, but have not yet found satisfactory acceptance in morphology. Improvements in non-invasive imaging and three-dimensional visualization techniques, however, permit high-throughput analyses also of whole biological specimens, including museum material. These developments pave the way towards a digital era in morphology. Using sea urchins (Echinodermata: Echinoidea), we provide examples illustrating the power of these techniques. However, remote visualization, the creation of a specialized database, and the implementation of standardized, world-wide accepted data deposition practices prior to publication are essential to cope with the foreseeable exponential increase in digital morphological data

    3D characterisation of hydrogen environmentally assisted cracking during static loading of AA7449-T7651

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    In this investigation, synchrotron X-ray microtomography was used to perform 3D in situ observations of crack initiation and growth during hydrogen environmentally assisted cracking (HEAC) in tensile samples of AA7449-T7651. Two smooth tensile samples with a 1 mm diameter gauge section were held at a fixed displacement (≈30% of yield stress) in warm, moist air (≈76∘C, 73% relative humidity). The samples were then imaged repeatedly using X-ray tomography until they fractured completely. The tomograms showing the nucleation and evolution of intergranular cracks were correlated with electron microscopy fractographs. This enabled the identification of crack initiation sites and the characterisation of the crack growth behaviour relative to the microstructure. The samples were found to fracture within an environmental exposure time of 240 min. Some cracks in both samples nucleated within an exposure time of 80 min (33–40% of the total lifetime). Many cracks were found to nucleate both internally and at the sample surface. However, only superficial cracks contributed to the final fracture surface as they grew faster owing to the direct environmental exposure and the larger crack opening. HEAC occurred prominently via brittle intergranular cracking, and cracks were found to slow down when approaching grain boundary triple junctions. Additionally, crack shielding from nearby cracks and the presence of coarse Al–Cu–Fe particles at the grain boundaries were also found to temporarily reduce the crack growth rates. After prolonged crack growth, the HEAC cracks displayed ductile striations and transgranular fracture, revealing a change in the crack growth mechanism at higher stress intensity factors

    Direct access to millions of mutations by whole genome sequencing of an oilseed rape mutant population

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    Induced mutations are an essential source of genetic variation in plant breeding. Ethyl methanesulfonate (EMS) mutagenesis has been frequently applied, and mutants have been detected by phenotypic or genotypic screening of large populations. In the present study, a rapeseed M2 population was derived from M1 parent cultivar 'Express' treated with EMS. Whole genomes were sequenced from fourfold (4×) pools of 1988 M2 plants representing 497 M2 families. Detected mutations were not evenly distributed and displayed distinct patterns across the 19 chromosomes with lower mutation rates towards the ends. Mutation frequencies ranged from 32/Mb to 48/Mb. On average, 284 442 single nucleotide polymorphisms (SNPs) per M2 DNA pool were found resulting from EMS mutagenesis. 55% of the SNPs were C → T and G → A transitions, characteristic for EMS induced ('canonical') mutations, whereas the remaining SNPs were 'non-canonical' transitions (15%) or transversions (30%). Additionally, we detected 88 725 high confidence insertions and deletions per pool. On average, each M2 plant carried 39 120 canonical mutations, corresponding to a frequency of one mutation per 23.6 kb. Approximately 82% of such mutations were located either 5 kb upstream or downstream (56%) of gene coding regions or within intergenic regions (26%). The remaining 18% were located within regions coding for genes. All mutations detected by whole genome sequencing could be verified by comparison with known mutations. Furthermore, all sequences are accessible via the online tool 'EMSBrassica' (http://www.emsbrassica.plantbreeding.uni-kiel.de), which enables direct identification of mutations in any target sequence. The sequence resource described here will further add value for functional gene studies in rapeseed breeding

    Determination of the packing fraction in photonic glass using synchrotron radiation nanotomography

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    Photonic glass is a material class that can be used as photonic broadband reflectors, for example in the infrared regime as thermal barrier coating films. Photonic properties such as the reflectivity depend on the ordering and material packing fraction over the complete film thickness of up to 100 μm. Nanotomography allows acquiring these key parameters throughout the sample volume at the required resolution in a non-destructive way. By performing a nanotomography measurement at the PETRA III beamline P05 on a photonic glass film, the packing fraction throughout the complete sample thickness was analyzed. The results showed a packing fraction significantly smaller than the expected random close packing giving important information for improving the fabrication and processing methods of photonic glass material in the future

    The Role of ICG in Robot-Assisted Liver Resections

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    Introduction: Robotic-assisted liver surgery (RALS) with its known limitations is gaining more importance. The fluorescent dye, indocyanine green (ICG), is a way to overcome some of these limitations. It accumulates in or around hepatic masses. The integrated near-infrared cameras help to visualize this accumulation. We aimed to compare the influence of ICG staining on the surgical and oncological outcomes in patients undergoing RALS. Material and Methods: Patients who underwent RALS between 2014 and 2021 at the Department of General Surgery at the University Hospital Schleswig-Holstein, Campus Kiel, were included. In 2019, ICG-supported RALS was introduced. Results: Fifty-four patients were included, with twenty-eight patients (50.9%) receiving preoperative ICG. Hepatocellular carcinoma (32.1%) was the main entity resected, followed by the metastasis of colorectal cancers (17%) and focal nodular hyperplasia (15.1%). ICG staining worked for different tumor entities, but diffuse staining was noted in patients with liver cirrhosis. However, ICG-supported RALS lasted shorter (142.7 ± 61.8 min vs. 246.4 ± 98.6 min, p < 0.001), tumors resected in the ICG cohort were significantly smaller (27.1 ± 25.0 mm vs. 47.6 ± 35.2 mm, p = 0.021) and more R0 resections were achieved by ICG-supported RALS (96.3% vs. 80.8%, p = 0.075). Conclusions: ICG-supported RALS achieve surgically and oncologically safe results, while overcoming the limitations of RALS

    Anal Sac Adenocarcinoma with Vertebromedullary Metastasis in a Cocker Spaniel

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    Background: Several neoplasms can affect the perianal region, being the hepatic adenoma and the anal sac adenocarcinoma (ASAC), which is considered the most frequent. The ASAC is a malignant neoplasm originating from the secretory epithelium of the perianal apocrine glands and is rarely seen in veterinary medicine. The ASAC occurs mainly in adult to elderly canines with high metastasis rates. Patients may be asymptomatic or manifest discomfort and behavioral changes. In the presence of metastasis, the most frequent clinical signs are inappetence, coughing, dyspnea, and colorectal obstruction. Given this scenario, this paper aims to describe the clinical presentation, diagnostic examination, and necropsy findings of a Cocker Spaniel with ASAC and metastasis in the vertebral body, spinal cord, and cauda equina. Case: A 8-year-old neutered male Cocker Spaniel (12 kg of body mass) with a clinical history of non-ambulatory paraparesis was evaluated. The patient also presented tenesmus, difficulty to defecate, and the presence of nodules in the anal sac area. On the neurological examination, asymmetrical changes compatible with injury between L4-S3 were found. A complete blood count, serum biochemistry, and imaging exams such as plain radiography, abdominal ultrasonography (US), and magnetic resonance imaging (MRI) were requested. Blood count revealed anemia and neutrophilic leukocytosis and hypercalcemia. The liver showed increased echogenicity and thickened pancreas in the abdominal US scan. A slightly heterogeneous, vascularized mass with irregular borders was identified in the topographic region of the sublumbar lymph nodes; MRI images demonstrated an expansile formation in the ventral region of the lumbosacral spine, corresponding to the sublumbar lymph nodes and interruption of the cerebrospinal fluid at L5, suggestive of compression of the spinal cord and cauda equina. A presumptive diagnosis of perianal neoplasm with metastasis was made based on the complementary exams. The dog was referred to necropsy, which revealed a 4 cm tumor in the perianal region that invaded the pelvic canal. Multifocal nodules were present on the lung surface, liver, and kidneys, suggesting metastasis. On the cross-section of the spine, one could note the presence of the tumor in the vertebral bodies, spinal cord, and cauda equina from L5 to S3. Even with histopathological evaluation of the tumor, only the immunohistochemical analysis allowed us to confirm the anal sac adenocarcinoma. Discussion: Adenomas and carcinomas are perianal gland neoplasms common in adult and elderly male dogs; the Cocker Spaniel breed is among the most affected. The clinical signs presented by the patient, such as tenesmus and difficulty in adopting the posture of defecation, are common, although neurological changes are rare. As for metastasis, carcinomas of the perianal region present high chances of metastasis to organs including the liver, kidneys, and lungs, both lymphatically and hematogenously, but few studies have related these factors to neurological alterations  due to metastasis. We concluded that metastases from carcinomas to the spine must be considered a possible differential diagnosis in cases of patients presenting clinical signs that are compatible with spinal cord compression and a history of previous neoplasm. Keywords: canine perianal carcinoma, neoplasm, spinal cord metastasis. Título: Adenocarcinoma de saco anal com metástase vertebro-medular em um Cocker Spaniel Descritores: carcinoma perianal canino, neoplasma, metástase medula espinhal.Introdução: Diversas neoplasias podem acometer a região perianal, sendo o adenoma hepático e o adenocarcinoma do saco anal (ASA), considerados os mais frequentes. O ASAC é uma neoplasia maligna originada do epitélio secretor das glândulas apócrinas perianais e raramente é visto na medicina veterinária. O ASA ocorre principalmente em cães adultos a idosos com altas taxas de metástase. Os pacientes podem ser assintomáticos ou manifestar desconforto e alterações comportamentais. Na presença de metástase, os sinais clínicos mais frequentes são inapetência, tosse, dispneia e obstrução colorretal. Diante desse cenário, este trabalho tem como objetivo descrever a apresentação clínica, exame diagnóstico e achados de necropsia de um Cocker Spaniel com ASAC e metástase no corpo vertebral, medula espinhal e cauda equina.Caso: Foi avaliado um macho castrado da raça Cocker Spaniel (12 kg de massa corporal) de oito anos de idade com história clínica de paraparesia não deambulatória. A paciente também apresentava tenesmo, dificuldade para defecar e presença de nódulos na região do saco anal. Ao exame neurológico, foram encontradas alterações assimétricas compatíveis com lesão entre L4-S3. Foram solicitados hemograma completo, bioquímica sérica e exames de imagem como radiografia simples, ultrassonografia (US) abdominal e ressonância magnética (RM). O hemograma revelou anemia e leucocitose neutrofílica e hipercalcemia. O fígado mostrou ecogenicidade aumentada e pâncreas espessado na US abdominal. Identificou-se massa pouco heterogênea, vascularizada e de contornos irregulares na região topográfica dos linfonodos sublombares; As imagens de RM demonstraram formação expansiva na região ventral da coluna lombossacral, correspondendo aos linfonodos sublombares e interrupção do líquido cefalorraquidiano em L5, sugestiva de compressão da medula espinhal e cauda equina. O diagnóstico presuntivo de neoplasia perianal com metástase foi feito com base nos exames complementares. A cadela foi encaminhada para necropsia, que revelou tumoração de 4 cm na região perianal que invadia o canal pélvico. Nódulos multifocais estavam presentes na superfície pulmonar, fígado e rins, sugerindo metástase. No corte transversal da coluna, notou-se a presença do tumor nos corpos vertebrais, medula espinhal e cauda equina de L5 a S3. Mesmo com a avaliação histopatológica do tumor, apenas a análise imuno-histoquímica permitiu confirmar o adenocarcinoma do saco anal.Discussão: Adenomas e carcinomas são neoplasias das glândulas perianais comuns em cães machos adultos e idosos; a raça Cocker Spaniel está entre as mais afetadas. Os sinais clínicos apresentados pelo paciente, como tenesmo e dificuldade em adotar a postura de defecar, são comuns, embora alterações neurológicas sejam raras. Quanto à metástase, os carcinomas da região perianal apresentam grandes chances de metástase para órgãos como fígado, rins e pulmões, tanto por via linfática quanto hematogênica, porém poucos estudos relacionam esses fatores às alterações neurológicas decorrentes da metástase. Concluímos que metástases de carcinomas para a coluna devem ser consideradas um possível diagnóstico diferencial em pacientes que apresentam sinais clínicos compatíveis com compressão medular e história de neoplasia prévia

    Bringing Dicynodonts Back to Life: Paleobiology and Anatomy of a New Emydopoid Genus from the Upper Permian of Mozambique

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    Dicynodontia represent the most diverse tetrapod group during the Late Permian. They survived the Permo-Triassic extinction and are central to understanding Permo-Triassic terrestrial ecosystems. Although extensively studied, several aspects of dicynodont paleobiology such as, neuroanatomy, inner ear morphology and internal cranial anatomy remain obscure. Here we describe a new dicynodont (Therapsida, Anomodontia) from northern Mozambique: Niassodon mfumukasi gen. et sp. nov. The holotype ML1620 was collected from the Late Permian K5 formation, Metangula Graben, Niassa Province northern Mozambique, an almost completely unexplored basin and country for vertebrate paleontology. Synchrotron radiation based micro-computed tomography (SRµCT), combined with a phylogenetic analysis, demonstrates a set of characters shared with Emydopoidea. All individual bones were digitally segmented allowing a 3D visualization of each element. In addition, we reconstructed the osseous labyrinth, endocast, cranial nerves and vasculature. The brain is narrow and the cerebellum is broader than the forebrain, resembling the conservative, "reptilian-grade" morphology of other non-mammalian therapsids, but the enlarged paraflocculi occupy the same relative volume as in birds. The orientation of the horizontal semicircular canals indicates a slightly more dorsally tilted head posture than previously assumed in other dicynodonts. In addition, synchrotron data shows a secondary center of ossification in the femur. Thus ML1620 represents, to our knowledge, the oldest fossil evidence of a secondary center of ossification, pushing back the evolutionary origins of this feature. The fact that the specimen represents a new species indicates that the Late Permian tetrapod fauna of east Africa is still incompletely known.Mozambique (Ministério dos Recursos Minerais), National Geographic Society, TAP airlines and other anonymous patrons, financial support from DESY through the I-20110184 EC project

    Relative impacts of land-use and climate change on grasshopper range shifts have changed over time

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    CITATION: Poniatowski, D. et al. 2020. Relative impacts of land-use and climate change on grasshopper range shifts have changed over time. Global Ecology and Biogeography 29(12): 2190– 2202. doi:10.1111/geb.13188The original publication is available at https://onlinelibrary.wiley.com/journal/14668238Aim: Stopping the decline of biodiversity is one of today’s greatest challenges. To help address this, we require studies that disentangle the effects of the most important drivers behind species range losses and shifts. In this large-scale study, we aim to evaluate the relative impacts of changes in land use and climate on distributional changes in grasshoppers. Location: Central Europe. Time period: Historical (pre-1990 vs. 1990–1999); recent (1990–1999 vs. 2000–2017). Major taxa studied: Orthoptera (hereafter referred to as grasshoppers). Methods: We used an advanced modelling approach within the framework of spatial point pattern analysis (SPPA) to calculate distributional changes of 58 grasshopper species based on > 100,000 aggregated observational records. Historical and recent range shifts were compared among four functional groups and analysed against: (a) the species temperature index (STI); and (b) the species farmland index (SFI). Results: During the earlier historical period, most species suffered from large range losses, with habitat specialists declining more than generalists with equal mobility. Range retractions were related to species with high SFI values; that is, species associated with farmland having a high natural value. In contrast, during the recent period the distribution of less mobile species generally remained stable, whereas highly mobile species even expanded their ranges, irrespective of their habitat specificity. Additionally, range expansions occurred mostly among thermophilic species; that is, those with high STI values. Main conclusions: This is the first large-scale study world-wide that quantifies both historical and recent range shifts of numerous grasshopper species. Our results suggest that historical range losses were mainly caused by severe loss of semi-natural habitats pre-1990. Recently, global warming has led to range expansions of several grasshopper species. The challenge now is to ensure the persistence of species that might not be able to evade future climate change owing to the increasing lack of suitable refuge habitats in intensive agricultural landscapes.https://onlinelibrary.wiley.com/doi/full/10.1111/geb.1318
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