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Spatial chromatin organization is crucial for transcriptional regulation and might be particularly important in neurons since they dramatically change their transcriptome in response to external stimuli. We show that stimulation of neurons causes condensation of large chromatin domains. This phenomenon can be observed in vitro in cultured rat hippocampal neurons as well as in vivo in the amygdala and hippocampal neurons. Activity-induced chromatin condensation is an active, rapid, energy-dependent, and reversible process. It involves calcium-dependent pathways but is independent of active transcription. It is accompanied by the redistribution of posttranslational histone modifications and rearrangements in the spatial organization of chromosome territories. Moreover, it leads to the reorganization of nuclear speckles and active domains located in their proximity. Finally, we find that the histone deacetylase HDAC1 is the key regulator of this process. Our results suggest that HDAC1-dependent chromatin reorganization constitutes an important level of transcriptional regulation in neurons., This work was supported by the National Science Centre grant nos. UMO-2015/18/E/NZ3/00730 (A.M., A.G., H.S.N., E.J. and Y.Y.), 2014/15/N/NZ2/00379 and 2017/24/T/NZ2/00307 (P.T.), 2019/35/O/ST6/02484 (D.P. and G.B.), and 2014/14/M/NZ4/00561 (K.H.O. and R.K.F.). B.W. and B.G. were supported by the Foundation for Polish Science TEAM-TECH Core Facility project “NGS platform for comprehensive diagnostics and personalized therapy in neuro-oncology,” Foundation for Polish Science co-financed by the European Union under the European Regional Development Fund (TEAM to D.P.). A.M.G. was supported by the H2020-MSCA-COFUND-2014 grant Bio4Med (GA no. 665735).

Cancer patients often experience loss in body weight and also a decrease in muscle mass, which results in the reduction of physical activity and mobilization of the patient. To decelerate the loss of muscle mass, as part of the cancer treatment patients frequently undergo physical therapy and considering the physical capabilities of the patients, with moderate loads. Moreover, frequent studies also observed for cancer patients, together with the decrease in muscle mass a shift into fast-twitch muscle fibers from slow-twitch fibers. The aim of our study therefore was to determine how motor fibers behave under moderate isometric load executed until total exhaustion. 11 university students (G1), and 14 elite athletes (G2) participated in the study. 65% of the maximal voluntary contraction (MVC) was determined for the biceps brachii muscle, and with this load holding a weight, participants had to sustain a 90 deg. isometric elbow flexion in a standing posture until complete fatigue occurred. EMG activity for the biceps brachii muscle was measured and frequency analysis was performed. 3 windows were determined in the fatiguing protocol: the first (W1), middle (W2), and last (W3) 5 s, and also frequency analysis for MVC was performed (MAX) between 0 and 260 Hz with 20 Hz wide frequency bands. The results indicate, that as the protocol progressed in time and the effect of fatigue increased (from W1 to W3) the activity of low frequency muscle fibers significantly increased (0-40 Hz) while activity of high frequency muscle fibers (60-260 Hz) significantly decreased for G1 and G2 groups identically. We can conclude, that training applied with constant moderate tension as fatigue increases will result in the increased activation of the lower frequency slow–twitch muscle fibers, but the increase of fatigue in the lower frequency fibers will not result in the increase in the activation level of the higher frequency fast-twitch fibers. Consequently, because as slow-twitch fibers are being used at moderate loads and even when fatigue occurs in these fibers the fast-twitch fibers will not work, higher muscle loads are needed if the aim is to activate fast-twitch fibers. Considering the shift into fast-twitch muscle fibers from slow-twitch fibers for cancer patients, in some cases if the patient’s age and physical status allows during the physical treatment, higher loads and consequently higher levels of activation might be beneficial for the retardment of loss concerning the fast-twitch fiber mass.

Jednym z fundamentalnych pytań w dziedzinie biologii jest to, w jaki sposób dwumetrowa nić DNA upakowana jest w jądrze o średnicy około 10 µm. Odpowiedzi na to pytanie udzielić może mikroskopia XXI w. Choć pierwsze mikroskopy powstały już w XVI w., to dopiero od kilkunastu lat (dzięki obejściu bariery dyfrakcyjnej ograniczającej rozdzielczość) możemy mówić o mikroskopii superrozdzielczej. Z każdym rokiem zaawansowane techniki mikroskopowe, wraz z rozwojem metod biochemicznych oraz obliczeniowych, przybliżają nas do odpowiedzi na to pytanie. Niniejsza praca ma na celu przedstawienie Czytelnikowi wstępu do badań nad organizacją chromatyny oraz przegląd technik mikroskopowych stosowanych w tych badaniach, z uwzględnieniem ich zalet oraz ograniczeń. Przy każdej z metod przedstawiono przykłady prac i odkryć uzyskanych dzięki nim. Ponieważ mikroskopia rozwija się bardzo dynamicznie w przeciągu ostatnich kilkunastu lat, opisane zostały w większości przypadków prace najnowsze. Przykłady te pozwalają Czytelnikowi zorientować się w postępie w badaniach nad organizacją chromatyny, a także (w połączeniu z opisem samych technik) w wybraniu odpowiednich metod obrazowania na etapie planowania własnych badań.

BackgroundBioimaging techniques offer a robust tool for studying molecular pathways and morphological phenotypes of cell populations subjected to various conditions. As modern high resolution 3D microscopy provides access to an ever-increasing amount of high quality images, there arises a need for their analysis in an automated, unbiased and simple way.Segmentation of structures within cell nucleus, which is the focus of this paper, presents a new layer of complexity in the form of dense packing and significant signal overlap.At the same time the available segmentation tools provide a steep learning curve for new users with limited technical background. This is especially apparent in bulk processing of image sets, which requires the use of some form of programming notation.ResultsIn this paper, we present PartSeg, a tool for segmentation and reconstruction of 3D microscopy images, optimised for the study of cell nucleus. PartSeg integrates refined versions of several state-of-the-art algorithms, including a new multi-scale approach for segmentation and quantitative analysis of 3D microscopy images.The features and user-friendly interface of PartSeg were carefully planned with biologists in mind, based on analysis of multiple use cases and difficulties encountered with other tools, to offer ergonomic interface with a minimal entry barrier. Bulk processing in an ad-hoc manner is possible without the need for programmer support. As the size of datasets of interest grows, such bulk processing solutions become essential for proper statistical analysis of results.Advanced users can use PartSeg components as a library within Python data processing and visualisation pipelines, for example within Jupyter notebooks. The tool is extensible so that new functionality and algorithms can be added by the use of plugins.For biologists the utility of PartSeg is presented in several scenarios, showing the quantitative analysis of nuclear structures.ConclusionsIn this paper, we have presented PartSeg which is a tool for precise and verifiable segmentation and reconstruction of 3D microscopy images. PartSeg is optimised for cell nucleus analysis and offers multiscale segmentation algorithms best-suited for this task. PartSeg can also be used for bulk processing of multiple images and its components can be reused in other systems or computational experiments.Contactg.bokota@cent.uw.edu.pl, a.magalska@nencki.edu.pl, d.plewczynski@cent.uw.edu.pl

Spatial chromatin organization is crucial for transcriptional regulation and might therefore be particularly dynamic in neurons since these terminally differentiated cells dramatically change their transcriptome in response to external stimuli. Here, we show that stimulation of neurons causes condensation of large chromatin domains. We find that this phenomenon is not only induced in rat hippocampal neurons cultured in vitro, but is also present in vivo in amygdala neurons of rats subjected to fear conditioning, and hippocampal neurons of animals subjected to kainate evoked seizures or High-Frequency Stimulation (HFS). The activity-induced chromatin condensation is an active, very rapid, and reversible process, that is independent of transcription and precedes the expression of Immediate Early Genes (IEG). It is accompanied by the redistribution of posttranslational modifications of histones, and rearrangements in the spatial organization of chromosome territories. Moreover, it leads to the reorganization of nuclear speckles and active domains located in their proximity. Finally, we find that neurons depleted of the histone deacetylase HDAC1 fail to condense chromatin upon stimulation, a phenomenon that can be fully reversed by the introduction of human HDAC1. Taken together, our results suggest that the HDAC1-dependent chromatin reorganization might constitute an important level of fine-tuning of transcriptional regulation in stimulated neurons.

Purpose The multidimensional role of hamstring muscle group strength in athletic performance and injury prevention is well documented, and nordic hamstring exercise (NHE) is a popular method for the development of hamstring strength. Our aim was to examine the EMG characteristics of the eccentric NHE as well as the effects of long-term eccentric NHE training on muscle strength and vertical jump performance in 10- to 11-year-old female handball players. Methods Players from the same handball team were randomly assigned to an eccentric NHE training (13 players) or a control group (10 players). Both groups continued their regular handball training routine, but the NHE group performed additional eccentric NHE exercises once or twice a week, with progressively increasing volume, over 20 weeks. To test training effects, countermovement jump (CMJ) height, eccentric hamstring impulse, peak torque, and angle of peak torque were evaluated before, during and after the training period. In the pre-exercise test, EMG activity of the medial and lateral hamstring muscle was also assessed during NHE. Results Hamstring activities ranged between 98 and 129%. Lateral hamstring activity was greater than medial only in the right leg during NHE. Eccentric hamstring impulse improved in both legs at 10 weeks in both groups. Then, at 20 weeks, it remained unchanged in the NHE but decreased in controls. A similar adaptation was seen in eccentric hamstring torque, without change in the optimum knee angle. CMJ height improved only in the NHE. Conclusion It is concluded that NHE activates the hamstring musculature effectively, and a favourable mechanical adaptation to long-term NHE exercise in girls can be triggered as early as 11 years of age.

OBJECTIVE Constitutional delay of growth and puberty (CDGP) is a tempo variant with a good prognosis. Healthy late-maturing adolescents grow slower than postulated by age-related references, and therefore, CDGP is frequently confused with growth hormone deficiency (GHD). For differential diagnosis, height velocity references for CDGP are needed. DESIGN AND PATIENTS Here, we provide height velocity data for late-maturing boys based on mixed longitudinal and cross-sectional observations in a group of 38 German adolescents with proven CDGP and compare them with cross-sectional observations in a group of 164 adolescents with organic GHD from the National Cooperative Growth Study registry. RESULTS In the critical age interval from 13.4 to 14.9 years, the growth of prepubertal adolescents with CDGP was faster (mean/median height velocity, 5.2/5.4 cm/years; quartiles, 4.4-6.2 cm/years) than that of prepubertal adolescents with organic GHD (3.5/3.2 cm/years; quartiles, 2.0-4.4 cm/years) in the cross-sectional analysis (p

The human genome is extensively folded into 3-dimensional organization, yet the detailed 3D chromatin folding structures have not been fully visualized due to the lack of robust and ultra- resolution imaging capability. Here, we report the development of a novel electron microscopy method that combines serial block-face scanning electron microscopy with in situ hybridization (3D-EMISH) to visualize 3D chromatin folding at targeted genomic regions with ultra-resolution (5×5×30 nm in xyz dimensions, respectively). We applied 3D-EMISH to human lymphoblastoid cells at a 1.7 Mb segment of the genome and visualized a large number of distinctive 3D chromatin folding structures in high ultra-resolution. We further quantitatively characterized the reconstituted chromatin folding structures by identifying sub-domains, and uncovered a high level of heterogeneity in chromatin folding ultrastructures, suggestive of extensive dynamic fluidity in 3D chromatin states.

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Background Recent efficacy studies of asthma biologics have included highly enriched patient populations. Using a similar approach, we examined factors that predict response to omalizumab to facilitate selection of patients most likely to derive the greatest clinical benefit from therapy. Methods Data from two phase III clinical trials of omalizumab in patients with allergic asthma were examined. Differences in rates of asthma exacerbations between omalizumab and placebo groups during the 16-week inhaled corticosteroid (ICS) dose-stable phase were evaluated with respect to baseline blood eosinophil counts (eosinophils

Asthma is one of the most common chronic diseases of childhood. Allergen sensitization and high frequencies of comorbid allergic diseases are characteristic of severe asthma in children. Omalizumab, an anti-IgE mAb, is the first targeted biologic therapeutic approved for the treatment of moderate-to-severe persistent allergic asthma (AA) that remains uncontrolled despite high-dose inhaled corticosteroids plus other controller medications. Since its initial licensing for use in adults and adolescents 12 years of age and older, the clinical efficacy, safety, and tolerability of omalizumab have been demonstrated in several published clinical trials in children aged 6 to less than 12 years with moderate-to-severe AA. These studies supported the approval of the pediatric indication (use in children aged ≥6 years) by the European Medicines Agency in 2009 and the US Food and Drug Administration in 2016. After this most recent change in licensing, we review the outcomes from clinical trials in children with persistent AA receiving omalizumab therapy and observational studies from the past 7 years of clinical experience in Europe. Data sources were identified by using PubMed in 2016. Guidelines and management recommendations and materials from the recent US Food and Drug Administration's Pediatric Advisory Committee meeting are also reviewed.

The aim of this study was to review the literature dealing with the force-time characteristics of different forms of physical activity performed with upper limbs by the elderly and the disabled (Nordic Walking and using a wheelchair, respectively) and of manual techniques used by physiotherapists. Values of work and power were analysed as well. Based on the analysis of the literature concerning the substantive areas included in this article, we believe that objective measurements will expand the present knowledge about values of force developed by upper limbs during different forms of human activity. It seems to be of particular significance in the application of manual therapy techniques, because currently values of force exerted upon the patient while applying these techniques are selected by a physiotherapist intuitively and are neither objective nor systematically controlled. The identification of the values of force developed with upper limbs by the elderly, the disabled and physiotherapists during the aforementioned forms of activity will make an original contribution to the broadly defined physical culture, especially rehabilitation and health promotion.

Introduction: Emicizumab is a subcutaneously administered, bispecific, humanized monoclonal antibody that bridges factor (F)IXa and FX to restore the function of missing activated FVIII in persons with hemophilia A (PwHA). This study (NCT03361137) was designed to evaluate the safety and efficacy of emicizumab prophylaxis in PwHA with or without FVIII inhibitors undergoing minor surgical procedures without additional prophylaxis with bypassing agents (BPAs; for patients with FVIII inhibitors) or FVIII (for patients without FVIII inhibitors). Methods: This Phase IV, multicenter, single-arm, open-label study enrolled PwHA of any age, with or without FVIII inhibitors, who were scheduled to undergo minor surgical procedures. Patients were required to have received a minimum of four loading doses of emicizumab (3mg/kg once weekly for 4 weeks) prior to surgical procedure; subsequent maintenance doses of emicizumab were 1.5mg/kg once weekly, 3mg/kg every 2 weeks, or 6mg/kg every 4 weeks. Patients were required to be adherent to emicizumab prophylaxis. Treatment with emicizumab was scheduled to continue for at least 1 month after surgery. No other prophylactic treatment with coagulation factor was permitted. Outcome measures included incidence of excessive bleeding intra-operatively and until discharge from surgery, use of BPAs or FVIII to control bleeding (intra- and post-operatively), incidence of adverse events (AEs), and the percentage of patients with complications requiring hospitalization or return to surgery. Excessive bleeding was defined as a rating of fair to poor on the hemostatic rating scale and translates to an intra- and/or post-operative blood loss of ≥25% over expectation for a patient without hemophilia prior to discharge from surgery. Patients were followed for 28 days following discharge from surgery. Results: Between June 28, 2018 and March 13, 2020, 14 PwHA undergoing minor surgeries were enrolled (with FVIII inhibitors n=11; without FVIII inhibitors n=3); one PwHA with FVIII inhibitors enrolled but did not have surgery and discontinued prematurely, therefore the surgery analysis population comprised 13 patients (with FVIII inhibitors n=10; without FVIII inhibitors n=3). The majority (78.6%) of those enrolled were Conclusions: In this study of mostly pediatric PwHA with and without FVIII inhibitors receiving emicizumab prophylaxis, minor surgeries were safely performed. The majority of surgeries were performed without additional prophylactic coagulation factor, however the small sample size should be considered here. There were no serious AEs, TEs, TMAs, or deaths. These findings are consistent with results from previous studies of patients undergoing minor surgery while receiving emicizumab prophylaxis. Disclosures Escobar: National Hemophilia Foundation: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genentech, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees. Dunn:Genentech, Inc.: Consultancy; Nationwide Children's Hospital: Current Employment; World Federation of Hemophilia USA: Membership on an entity's Board of Directors or advisory committees; Medscape: Honoraria; Spire: Honoraria; ATHN: Research Funding; Takeda: Research Funding; BioMarin: Research Funding; uniQure: Consultancy. Quon:Octapharma: Honoraria; Bayer: Honoraria; Biomarin: Honoraria, Speakers Bureau; Bioverativ/Sanofi: Honoraria, Speakers Bureau; Genentech, Inc./F. Hoffmann-La Roche Ltd: Honoraria, Speakers Bureau; Novo Nordisk: Honoraria, Speakers Bureau; Shire/Takeda: Speakers Bureau; Orthopaedic Institute for Children: Current Employment. Trzaskoma:Genentech, Inc.: Current Employment, Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months. Lee:Genentech, Inc.: Current Employment; F. Hoffmann-La Roche Ltd: Current equity holder in publicly-traded company. Ko:Genentech, Inc.: Current Employment; F. Hoffmann-La Roche Ltd: Current equity holder in publicly-traded company. Carpenter:Novo Nordisk: Honoraria; Genentech, Inc.: Honoraria; American Thrombosis and Hemostasis Network: Membership on an entity's Board of Directors or advisory committees; CSL Behring: Research Funding; Shire: Research Funding; Hemostasis & Thrombosis Research Society: Membership on an entity's Board of Directors or advisory committees; American Academy of Pediatrics: Other: PREP Heme/Onc editorial board; Kedrion: Honoraria.