214 research outputs found

    Morphology and Nanomechanics of Sensory Neurons Growth Cones following Peripheral Nerve Injury

    Get PDF
    A prior peripheral nerve injury in vivo, promotes a rapid elongated mode of sensory neurons neurite regrowth in vitro. This in vitro model of conditioned axotomy allows analysis of the cellular and molecular mechanisms leading to an improved neurite re-growth. Our differential interference contrast microscopy and immunocytochemistry results show that conditioned axotomy, induced by sciatic nerve injury, did not increase somatic size of adult lumbar sensory neurons from mice dorsal root ganglia sensory neurons but promoted the appearance of larger neurites and growth cones. Using atomic force microscopy on live neurons, we investigated whether membrane mechanical properties of growth cones of axotomized neurons were modified following sciatic nerve injury. Our data revealed that neurons having a regenerative growth were characterized by softer growth cones, compared to control neurons. The increase of the growth cone membrane elasticity suggests a modification in the ratio and the inner framework of the main structural proteins

    Hypoxic conditioning in Parkinson’s disease: randomized controlled multiple N-of-1 trials

    Get PDF
    Preclinical evidence suggests positive symptomatic and neuroprotective effects of hypoxic conditioning in Parkinson’s disease (PD). This study (NCT05214287) investigated the safety, feasibility, short-term symptomatic and downstream effects of hypoxic conditioning in individuals with PD. 20 individuals with PD (mean age 62, 10 women, Hoehn-Yahr 1.5-3) completed randomized controlled double-blinded multiple N-of-1 trials. Each participant underwent five different 45-minute hypoxia interventions in duplicate: continuous hypoxia at FiO20.163 and 0.127, intermittent (five-minute intervals interspersed with normoxia) at FiO2 0.163 and 0.127, and placebo. Primary outcomes were safety and feasibility as measured by adverse events, vital parameter disturbances, participant-rated discomfort and feasibility questionnaires. Secondary outcomes were short-term participant-rated and assessor-rated symptom scores. Exploratory indicators of target engagement were serum erythropoietin, brain-derived neurotrophic factor (BDNF), glial fibrillary acidic protein (GFAP), neurofilament light-chain (NfL), platelet-derived growth factor-receptor-β (PDGFRβ) and cortisol. Secondary outcomes were evaluated using frequentist and Bayesian analysis. 20 participants completed the protocol. The trial met its primary endpoints for safety and feasibility. 95 adverse events occurred, including one moderate and three serious events. Adverse events were not dose-dependent and occurred at comparable incidence following hypoxia and placebo. Hypoxic conditioning was well-tolerated. Low-FIO2 protocols caused significant oxygen desaturations in two participants. Participants considered longer-term application feasible. Intermittent hypoxia at FIO20.163 modestly improved most participant-rated symptoms for several hours compared to placebo, but not assessor-rated scales. One hour after intervention, serum markers did not differ between interventions. Hypoxic conditioning is safe and feasible in individuals with PD, and specific protocols may be associated with short-term symptom improvement. These findings inform and support follow-up studies of longer-term safety and efficacy of hypoxic conditioning

    Randomized controlled trial of intermittent hypoxia in Parkinson’s disease: study rationale and protocol

    Get PDF
    Background Parkinson’s disease (PD) is a neurodegenerative disease for which no disease-modifying therapies exist. Preclinical and clinical evidence suggest that repeated exposure to intermittent hypoxia might have short- and long-term benefits in PD. In a previous exploratory phase I trial, we demonstrated that in-clinic intermittent hypoxia exposure is safe and feasible with short-term symptomatic effects on PD symptoms. The current study aims to explore the safety, tolerability, feasibility, and net symptomatic effects of a four-week intermittent hypoxia protocol, administered at home, in individuals with PD. Methods/Design: This is a two-armed double-blinded randomized controlled trial involving 40 individuals with mild to moderate PD. Participants will receive 45 min of normobaric intermittent hypoxia (fraction of inspired oxygen 0.16 for 5 min interspersed with 5 min normoxia), 3 times a week for 4 weeks. Co-primary endpoints include nature and total number of adverse events, and a feasibility-tolerability questionnaire. Secondary endpoints include Movement Disorders Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) part II and III scores, gait tests and biomarkers indicative of hypoxic dose and neuroprotective pathway induction. Discussion This trial builds on the previous phase I trial and aims to investigate the safety, tolerability, feasibility, and net symptomatic effects of intermittent hypoxia in individuals with PD. Additionally, the study aims to explore induction of relevant neuroprotective pathways as measured in plasma. The results of this trial could provide further insight into the potential of hypoxia-based therapy as a novel treatment approach for PD

    Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

    Get PDF
    Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics

    Morphometrical analysis of transbronchial cryobiopsies

    Get PDF
    The recent introduction of bronchoscopically recovered cryobiopsy of lung tissue has opened up new possibilities in the diagnosis of neoplastic and non-neoplastic lung diseases in various aspects. Most notably the morphological diagnosis of peripheral lung biopsies promises to achieve a better yield with a high quality of specimens. To better understand this phenomenon, its diagnostic options and perspectives, this study morphometrically compares 15 cryobiopsies and 18 transbronchial forceps biopsies of peripheral lung tissue a priori without considering clinical hit ratio or integration of results in the clinical diagnostic processing. Cryotechnically harvested specimens were significantly larger (mean: 17.1 ± 10.7 mm2 versus 3.8 ± 4.0 mm2) and contained alveolar tissue more often. If present, the alveolar part in cryobiopsies exceeded the one of forceps biopsies. The alveolar tissue of crybiopsy specimens did not show any artefacts. Based on these results cryotechnique seems to open up new perspectives in bronchoscopic diagnosis of lung disease

    Linkage mapping of the Phg-1 and Co-14 genes for resistance to angular leaf spot and anthracnose in the common bean cultivar AND 277

    Get PDF
    The Andean common bean AND 277 has the Co-14 and the Phg-1 alleles that confer resistance to 21 and eight races, respectively, of the anthracnose (ANT) and angular leaf spot (ALS) pathogens. Because of its broad resistance spectrum, Co-14 is one of the main genes used in ANT resistance breeding. Additionally, Phg-1 is used for resistance to ALS. In this study, we elucidate the inheritance of the resistance of AND 277 to both pathogens using F2 populations from the AND 277 × Rudá and AND 277 × Ouro Negro crosses and F2:3 families from the AND 277 × Ouro Negro cross. Rudá and Ouro Negro are susceptible to all of the above races of both pathogens. Co-segregation analysis revealed that a single dominant gene in AND 277 confers resistance to races 65, 73, and 2047 of the ANT and to race 63-23 of the ALS pathogens. Co-14 and Phg-1 are tightly linked (0.0 cM) on linkage group Pv01. Through synteny mapping between common bean and soybean we also identified two new molecular markers, CV542014450 and TGA1.1570, tagging the Co-14 and Phg-1 loci. These markers are linked at 0.7 and 1.3 cM, respectively, from the Co-14/Phg-1 locus in coupling phase. The analysis of allele segregation in the BAT 93/Jalo EEP558 and California Dark Red Kidney/Yolano recombinant populations revealed that CV542014450 and TGA1.1570 segregated in the expected 1:1 ratio. Due to the physical linkage in cis configuration, Co-14 and Phg-1 are inherited together and can be monitored indirectly with the CV542014450 and TGA1.1570 markers. These results illustrate the rapid discovery of new markers through synteny mapping. These markers will reduce the time and costs associated with the pyramiding of these two disease resistance genes

    A core outcome set for future male infertility research: development of an international consensus

    Get PDF
    \ua9 The Author(s). Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology.STUDY QUESTION: Can a core outcome set be developed through a global consensus to standardize outcome selection, collection, comparison, and reporting in future male infertility trials? SUMMARY ANSWER: A minimum dataset, known as a \u27core outcome set\u27, has been developed for randomized controlled trials (RCTs) and systematic reviews evaluating potential interventions for male infertility. WHAT IS KNOWN ALREADY: Numerous factors, including a failure to consider the perspectives of men with lived experiences of infertility or their partners when developing and conducting RCTs can limit their clinical utility. Selection of outcomes, variations in outcome definitions, and the selective reporting of outcomes based on statistical analysis make the results of infertility research challenging to interpret, compare, and implement. For male infertility, this is further compounded by there being potentially three participants, the male, their female partner, and any offspring born, all with outcomes to be reported. This has led to significant heterogeneity in trial design and reporting. While a core outcome set for general infertility trials has been developed, there is no such outcome set for male infertility trials. STUDY DESIGN, SIZE, DURATION: A two-round Delphi survey (334 participants from 39 countries) and consensus development workshops (44 participants from 21 countries). PARTICIPANTS/MATERIALS, SETTING, METHODS: Healthcare professionals, researchers, and men and women with infertility were brought together in a transparent process using formal consensus science methods. MAIN RESULTS AND THE ROLE OF CHANCE: The core outcome set for male infertility trials has been developed by the inclusion of specific male-factor outcomes in addition to the general infertility core outcome set. These outcomes include assessment of semen using the World Health Organization recommendations for semen analysis; viable intrauterine pregnancy confirmed by ultrasound (accounting for singleton, twin, and higher multiple pregnancies); pregnancy loss (accounting for ectopic pregnancy, miscarriage, stillbirth, and termination of pregnancy); live birth; gestational age at delivery; birthweight; neonatal mortality; and major congenital anomaly. Although not a requirement as part of the core outcome set, other outcomes were identified as potentially useful in certain study settings. LIMITATIONS, REASONS FOR CAUTION: We used consensus development methods in this work, which have inherent limitations, including the representativeness of the participant sample, Delphi survey attrition, and an arbitrary consensus threshold. WIDER IMPLICATIONS OF THE FINDINGS: Embedding the core outcome set within RCTs and systematic reviews should ensure the comprehensive selection, collection, and reporting of core outcomes, which are inconsistently reported at present. Research funding bodies, the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) statement, and over 80 specialty journals, including the Cochrane Gynaecology and Fertility Group, Fertility and Sterility and Human Reproduction, have committed to implementing this core outcome set for male infertility trials

    A combined functional and structural genomics approach identified an EST-SSR marker with complete linkage to the Ligon lintless-2 genetic locus in cotton (Gossypium hirsutum L.)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Cotton fiber length is an important quality attribute to the textile industry and longer fibers can be more efficiently spun into yarns to produce superior fabrics. There is typically a negative correlation between yield and fiber quality traits such as length. An understanding of the regulatory mechanisms controlling fiber length can potentially provide a valuable tool for cotton breeders to improve fiber length while maintaining high yields. The cotton (<it>Gossypium hirsutum </it>L.) fiber mutation Ligon lintless-2 is controlled by a single dominant gene (<it>Li<sub>2</sub></it>) that results in significantly shorter fibers than a wild-type. In a near-isogenic state with a wild-type cotton line, <it>Li<sub>2 </sub></it>is a model system with which to study fiber elongation.</p> <p>Results</p> <p>Two near-isogenic lines of Ligon lintless-2 (<it>Li<sub>2</sub></it>) cotton, one mutant and one wild-type, were developed through five generations of backcrosses (BC<sub>5</sub>). An F<sub>2 </sub>population was developed from a cross between the two <it>Li<sub>2 </sub></it>near-isogenic lines and used to develop a linkage map of the <it>Li<sub>2 </sub></it>locus on chromosome 18. Five simple sequence repeat (SSR) markers were closely mapped around the <it>Li<sub>2 </sub></it>locus region with two of the markers flanking the <it>Li<sub>2 </sub></it>locus at 0.87 and 0.52 centimorgan. No apparent differences in fiber initiation and early fiber elongation were observed between the mutant ovules and the wild-type ones. Gene expression profiling using microarrays suggested roles of reactive oxygen species (ROS) homeostasis and cytokinin regulation in the <it>Li<sub>2 </sub></it>mutant phenotype. Microarray gene expression data led to successful identification of an EST-SSR marker (NAU3991) that displayed complete linkage to the <it>Li<sub>2 </sub></it>locus.</p> <p>Conclusions</p> <p>In the field of cotton genomics, we report the first successful conversion of gene expression data into an SSR marker that is associated with a genomic region harboring a gene responsible for a fiber trait. The EST-derived SSR marker NAU3991 displayed complete linkage to the <it>Li<sub>2 </sub></it>locus on chromosome 18 and resided in a gene with similarity to a putative plectin-related protein. The complete linkage suggests that this expressed sequence may be the <it>Li<sub>2 </sub></it>gene.</p
    corecore