Elucidating the Mechanisms Surrounding H2A.X Monoubiquitylation Marks in the DNA Damage Response Pathway

In response to DNA double-strand breaks (DSBs), H2A.X undergoes three post-translational modifications (PTMs) reported to be important for DSB signaling: phosphorylation at serine 139, monoubiquitylation at lysines 118/119 and monoubiquitylation at lysines 13/15. We aimed to gain a better understanding of the mechanisms surrounding H2A.X monoubiquitylation marks and their relationship to H2A.X phosphorylation. We have developed and tested a novel purification method for the isolation of ubiquitylated H2A.X-containing nucleosomes, which can be used to co-purify DNA damage-response proteins that interact with ubiquitylated H2A.X-containing nucleosomes. Our data show that monoubiquitylation of lysines 118/119 is not required for phosphorylation at serine 139, nor for monoubiquitylation at lysines 13/15 in cis (on the same H2A.X molecule). Our data also suggests that monoubiquitylation of lysines 118/119 may have an antagonistic effect on monoubiquitylation of lysines 13/15. Lastly, we saw that different DSB-inducing agents can have different effects on H2A.X monoubiquitylation

Caracterização de caqui'kakimel' submetido ao choque de frio após destanização em Campina Grande do Sul - PR

Resumo: O caqui ‘Kakimel’ é cultivado principalmente em Campina Grande do Sul – Paraná e é muito apreciado pela doçura de sua polpa. Pertencente ao grupo dos caquis taninosos (adstringentes), os frutos necessitam passar por um processo de destanização para serem consumidos e isto também causa o amolecimento da polpa. Entre os métodos de destanização do caqui, a exposição ao vapor de álcool etílico é o mais utilizado na região de produção. Entretanto, segundo os produtores da Cooperativa dos Produtores de Campina Grande do Sul (CPCamp), há recuperação da adstringência após a destanização, o que eles atribuem ao estresse causado por um choque de frio durante o transporte destes frutos. Pesquisas sobre as características deste cultivar e seu processo de destanização são escassas no meio científico. Desta forma, surge a necessidade de se desenvolver tecnologias que promovam um eficiente processo de destanização do ‘Kakimel’, mantendo a qualidade destes frutos. Objetivou-se com esta pesquisa caracterizar os caquis ‘Kakimel’, remover a adstringência destes frutos com o uso de vapor de álcool etílico e medir a eficiência da manutenção da destanização nos frutos submetidos ao choque de frio após o tratamento. Os frutos foram expostos ao vapor de álcool etílico durante 12, 24, 36 e 48 horas e armazenados sob temperatura de 22 °C e 95% de umidade relativa. Após o tratamento, 50% dos frutos foram submetidos a um choque de frio a 6 °C por duas horas e retornaram às mesmas condições de armazenamento. Os outros 50% foram mantidos a uma temperatura de 22 °C e 95% de umidade relativa durante todo o período após a exposição ao vapor de álcool etílico. O experimento foi repetido nas safras de 2012 e 2013. A caracterização dos frutos foi realizada logo após a colheita e após os tratamentos (3, 5, 7, 9 e 11 dias de armazenamento). As variáveis analisadas foram: teor de taninos solúveis, massa fresca, pH, teor de sólidos solúveis, acidez titulável, firmeza e coloração da casca e da polpa. Os caquis ‘Kakimel’ produzidos em Campina Grande do Sul tem altos teores de taninos solúveis, com valores de 1,33 a 1,44%, sólidos solúveis variando de 17,61 a 16,48 °Brix, acidez titulável de 0,15 a 0,13% e pH de 5,54 a 5,50, com a coloração da casca passando de amarelo-alaranjado no momento da colheita para amarelo-avermelhado aos 11 dias após a colheita. A adstringência dos frutos foi removida após 3 dias nos frutos expostos ao vapor de álcool etílico por um período de 24 horas e após 5 dias nos frutos expostos ao vapor de álcool etílico por um período de 12 horas. O choque de frio não ocasiona a recuperação da adstringência dos frutos de caquizeiro ‘Kakimel’

Virtual consultation (VC) in fertility and obstetrics and gynaecology services: An analysis of patient and clinician satisfaction

Objective: To assess patient and clinician satisfaction and identify any differences between the two with the use of video consulting (VC) in the fields of obstetrics and gynaecology (O&G) and fertility in Wales. Design: A retrospective electronic survey study. Setting: All public hospitals in Wales that used virtual methods for delivery of fertility and/or O&G appointments during and after the COVID‐19 pandemic between August 2020 and March 2022. Population: Patients awaiting an appointment on the National Health Service, who have attended virtual fertility or O&G appointments in Wales, and fertility and O&G clinicians who have conducted appointments virtually. Methods: Analysis of patient and clinician responses to a VC satisfaction survey delivered after their consultation taking place between August 2020 and March 2022. Main Outcome Measures: Patient and clinician satisfaction rates with the use of virtual consultation in fertility and O&G appointments. Results: In satisfaction data collected from 420 patients and 161 clinicians, 83% of patients and 63% of clinicians reported their VC quality to be ‘very good’ or ‘excellent’. Difficulties when using VC were experienced by a minority of patients (1%–9%) and clinicians (1%–8%) and most patients (52v82%) and clinicians (34%–67%) found several aspects of VC to be ‘very beneficial’. Fertility patients rated their VC experience more positively than O&G patients. Conclusions: Most patients and clinicians were satisfied with their VC experience. Patients were more satisfied with the use of VC than clinicians. Fertility patients were more satisfied with the use of VC than O&G patients

Single Bead Affinity Detection (SINBAD) for the Analysis of Protein-Protein Interactions

We present a miniaturized pull-down method for the detection of protein-protein interactions using standard affinity chromatography reagents. Binding events between different proteins, which are color-coded with quantum dots (QDs), are visualized on single affinity chromatography beads by fluorescence microscopy. The use of QDs for single molecule detection allows the simultaneous analysis of multiple protein-protein binding events and reduces the amount of time and material needed to perform a pull-down experiment

The role of the cerebellum in multiple sclerosis—150 years after Charcot

Despite its functional importance and well known clinical impact in Multiple Sclerosis (MS), the cerebellum has only received significant attention over the past few years. It is now established that the cerebellum plays a key role not only in various sensory-motor networks, but also in cognitive-behavioural processes, domains primarily affected in patients with MS. Evidence from histopathological and magnetic resonance imaging (MRI) studies on cerebellar involvement in MS is increasingly available, however linking these pathological findings with clinical dysfunction remains challenging. There are promising advances in technology that are likely to improve the detection of pathological changes within the cerebellum, which may elucidate how pathology relates to disability

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM