1,054 research outputs found

    Machine phenotyping of cluster headache and its response to verapamil

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    Cluster headache is characterized by recurrent, unilateral attacks of excruciating pain associated with ipsilateral cranial autonomic symptoms. Although a wide array of clinical, anatomical, physiological, and genetic data have informed multiple theories about the underlying pathophysiology, the lack of a comprehensive mechanistic understanding has inhibited, on the one hand, the development of new treatments and, on the other, the identification of features predictive of response to established ones. The first-line drug, verapamil, is found to be effective in only half of all patients, and after several weeks of dose escalation, rendering therapeutic selection both uncertain and slow. Here we use high-dimensional modelling of routinely acquired phenotypic and MRI data to quantify the predictability of verapamil responsiveness and to illuminate its neural dependants, across a cohort of 708 patients evaluated for cluster headache at the National Hospital for Neurology and Neurosurgery between 2007 and 2017. We derive a succinct latent representation of cluster headache from non-linear dimensionality reduction of structured clinical features, revealing novel phenotypic clusters. In a subset of patients, we show that individually predictive models based on gradient boosting machines can predict verapamil responsiveness from clinical (410 patients) and imaging (194 patients) features. Models combining clinical and imaging data establish the first benchmark for predicting verapamil responsiveness, with an area under the receiver operating characteristic curve of 0.689 on cross-validation (95% confidence interval: 0.651 to 0.710) and 0.621 on held-out data. In the imaged patients, voxel-based morphometry revealed a grey matter cluster in lobule VI of the cerebellum (–4, –66, –20) exhibiting enhanced grey matter concentrations in verapamil non-responders compared with responders (familywise error-corrected P = 0.008, 29 voxels). We propose a mechanism for the therapeutic effect of verapamil that draws on the neuroanatomy and neurochemistry of the identified region. Our results reveal previously unrecognized high-dimensional structure within the phenotypic landscape of cluster headache that enables prediction of treatment response with modest fidelity. An analogous approach applied to larger, globally representative datasets could facilitate data-driven redefinition of diagnostic criteria and stronger, more generalizable predictive models of treatment responsiveness

    Characterization of tissue inhibitor metalloproteinases in semen and their relationship with vital sperm function tests vis-Ă -vis fertility of breeding buffalo bulls

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    The present study was undertaken to separate and compare the tissue inhibitor metalloproteinases (TIMP) of seminal plasma and frozen-thawed sperm extracts from 30 buffalo bulls by immunoblotting and determine a relationship between various TIMP with post-thaw sperm function tests vis-Ă -vis bull fertility. Seven immunoreactive bands in seminal plasma (65, 55, 48, 33, 31, 24 and 11 kDa) and 5 in frozen-thawed spermatozoa (75, 65, 55, 24 and 16 kDa) were detected in Western blots following incubation (TIMP–140) and subsequent washing in vitro, indicating that TIMP is bound to sperm membranes. The frozen-thawed semen was evaluated for first service conception rate (FSCR), per cent HOST, acrosome reaction, viability, DNA integrity and total motility and linked to TIMP. In seminal plasma, the bulls positive for 48, 33 and 24 kDa TIMP had significantly higher FSCR (57.0 ± 2.6 vs 27.0 ± 2.4%, 55.7 ± 3.0 vs 31.3 ± 3.2% and 45.0 ± 3.8 vs 32.8 ± 4.7%, respectively) as compared to their negative counterparts. Except per cent viability, almost all seminal parameters (acrosome reaction, per cent HOST, DNA integrity and total motility) were significantly higher in bulls positive for TIMP of 48, 33, 31 and 24 kDa than in their negative contemporary mates. In frozen-thawed sperm extracts, the bulls positive for TIMP–24 had significantly higher FSCR (51.7 ± 3.7 vs 27.2 ± 3.0%), higher percentage of acrosome-reacted (55.9 ± 2.8 vs 48.9 ± 2.2%) and HOS-positive (69.2 ± 1.5 vs 65.3 ± 1.9%) spermatozoa in comparison to their negative herd mates. These results suggested that TIMP influences semen quality and subsequent fertility of buffalo bulls through inhibition of metalloprotease activity in semen

    Osteomimetic matrix components alter cell migration and drug response in a 3D tumour-engineered osteosarcoma model

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    vulnerable to recurring disease and pulmonary metastases. Developing 3D in vitro disease models to serve as a test bed for personalised treatment is a promising approach to address this issue. This study describes the generation of 3D osteosarcoma models termed “tumouroids”, which are geometrically compartmentalised to reproduce the bone cancer mass and its surrounding. Although the tumour microenvironment impacts osteosarcoma in many ways, this model focussed on interrogating the influence of a biomimetic matrix on tumour cell behaviour. The 3D matrix was supplemented with the bone-marrow proteins laminin, fibronectin and NuOss¼ bone granules. This led to increased invasion of osteosarcoma cell aggregates from within the bone-like matrix into the surrounding acellular bone marrow-like ECM. The presence of bone granules also yielded an atypical molecular profile of osteosarcoma cells, suggesting malignant metabolic reprogramming. Changes include decreased MMP-9 (p < 0.05) and increased PTEN (p < 0.05), MCP-1 (p < 0.01) and MCT-4 (p < 0.05) gene expression. This complex 3D biomimetic composition also changed cellular responses to doxorubicin, a common chemotherapeutic agent used to treat osteosarcoma, and reproduced key issues of in vivo treatment like drug penetrance and doxorubicin-induced bone toxicity. This work highlights the importance of a biomimetic matrix in 3D osteosarcoma models for both basic and translational research

    A CO Funnel in the Galactic Centre: Molecular Counterpart of the Northern Galactic Chimney?

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    We report the discovery of a velocity coherent, funnel shaped ^13CO emission feature in the Galactic centre (GC) using data from the SEDIGISM survey. The molecular cloud appears as a low velocity structure (V_LSR=[-3.5, +3.5] km/s) with an angular extent of 0.95{\deg} x 1{\deg}, extending toward positive Galactic latitudes. The structure is offset from Sgr A* toward negative Galactic longitudes and spatially and morphologically correlates well with the northern lobe of the 430 pc radio bubble, believed to be the radio counterpart of the multiwavelength GC chimney. Spectral line observations in the frequency range of 85-116 GHz have been carried out using the IRAM 30 metre telescope toward 12 positions along the funnel-shaped emission. We examine the ^12C/^13C isotopic ratios using various molecules and their isotopologues. The mean ^12C/^13C isotope ratio (30.6+-2.9) is consistent with the structure located within inner 3 kpc of the Galaxy and possibly in the GC. The velocity of the molecular funnel is consistent with previous radio recombination line measurements of the northern lobe of radio bubble. Our multiwavelength analysis suggests that the funnel shaped structure extending over 100 pc above the Galactic plane is the molecular counterpart of the northern GC chimney.Comment: Accepted for publication in A&A Letter

    Prediction of buffalo bull fertility on the basis of sperm motion traits, viability, membrane integrity, heat shock protein (HSP70) expression and fertility associated antigen (FAA)

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    The present study was conducted on 20 buffalo bulls to predict the fertility on the basis of: (a) Computer assisted semen analysis (CASA) based sperm motion traits, (b) viability, (c) membrane integrity, (d) expression for HSP70, and (e) assessment of fertility associated antigen (FAA). Six frozen semen straws from each buffalo bulls were analyzed for sperm motion traits, viz. individual motility, progressive motility, average path velocity (VAP), straight line velocity (VSL), curvilinear velocity (VCL), amplitude of lateral head deviation (ALH), beat cross frequency (BCF), straightness (STR), linearity (LIN) and sperm size. Viability and hypoosmotic swelling tests (HOST) were also conducted. Heat shock protein 70 (HSP70) expression and quantification was conducted using a real time PCR. Fertility associated antigen (FAA) was assessed in fresh semen from buffalo bulls using test. Fertility trial was conducted on 250 normal cycling buffaloes following estrus synchronization with GnRH-PGF- GnRH protocol. It was concluded that buffalo bull fertility could be best predicted on the basis of sperm motion traits (VCL, VAP, VSL, ALH, LIN), motility, viability, HOST and HSP70 expression. However, FAA assessment in fresh semen did not indicate fertility

    1281O Atezolizumab (atezo) vs platinum-based chemo in blood-based tumour mutational burden-positive (bTMB+) patients (pts) with first-line (1L) advanced/metastatic (m)NSCLC: Results of the Blood First Assay Screening Trial (BFAST) phase III cohort C

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    Background: TMB is a promising biomarker for immunotherapy in NSCLC, but current data are mostly retrospective. As not all pts may have sufficient tissue for comprehensive biomarker testing, bTMB was prospectively tested as a novel biomarker using targeted next-generation sequencing. BFAST (NCT03178552), a global, open-label, multi-cohort trial, evaluated safety and efficacy of targeted therapies or immunotherapy in biomarker-selected pts with unresectable mNSCLC. Here we present results from Cohort C of 1L atezo vs platinum-based chemo in pts with bTMB+ mNSCLC. Methods: We planned to randomise ≈440 pts with 1L mNSCLC with measurable disease per RECIST 1.1 and bTMB ≄10 (9.1 mut/Mb; FMI bTMB assay) 1:1 to atezo 1200 mg IV every 3 weeks or chemo and stratified by tissue availability, ECOG PS, bTMB and histology. The primary endpoint was INV-PFS per RECIST 1.1 in bTMB ≄16 (14.5 mut/Mb) pts. Key secondary endpoints included OS in bTMB ≄10 (intent to treat, ITT) and bTMB ≄16 pts, and INV-PFS in ITT pts. Results: 471 pts were assigned to atezo (n=234) or chemo (n=237). At baseline, 72% had non-squamous histology, 2% never smoked and median SLD was 103 mm. 145 pts with bTMB ≄16 were assigned to atezo and 146 to chemo. At data cutoff (21 May 2020) minimum follow up was 6 mo. INV-PFS difference in bTMB ≄16 pts for atezo vs chemo was not significant (P=0.053; Table). Grade 3-4 TRAEs occurred in 18% (atezo) vs 46% (chemo) of pts. Serious TRAEs occurred in 12% (atezo) vs 14% (chemo). Results at other bTMB thresholds and by F1L CDx will also be presented as an exploratory analysis. Conclusions: The primary PFS endpoint in bTMB ≄16 pts was not met. OS was numerically better with atezo vs chemo but the difference was not statistically significant. The safety profile of atezo vs chemo was favourable and consistent with atezo monotherapy across indications

    Vertical transport and electroluminescence in InAs/GaSb/InAs structures: GaSb thickness and hydrostatic pressure studies

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    We have measured the current-voltage (I-V) of type II InAs/GaSb/InAs double heterojunctions (DHETs) with 'GaAs like' interface bonding and GaSb thickness between 0-1200 \AA. A negative differential resistance (NDR) is observed for all DHETs with GaSb thickness >> 60 \AA below which a dramatic change in the shape of the I-V and a marked hysteresis is observed. The temperature dependence of the I-V is found to be very strong below this critical GaSb thickness. The I-V characteristics of selected DHETs are also presented under hydrostatic pressures up to 11 kbar. Finally, a mid infra-red electroluminescence is observed at 1 bar with a threshold at the NDR valley bias. The band profile calculations presented in the analysis are markedly different to those given in the literature, and arise due to the positive charge that it is argued will build up in the GaSb layer under bias. We conclude that the dominant conduction mechanism in DHETs is most likely to arise out of an inelastic electron-heavy-hole interaction similar to that observed in single heterojunctions (SHETs) with 'GaAs like' interface bonding, and not out of resonant electron-light-hole tunnelling as proposed by Yu et al. A Zener tunnelling mechanism is shown to contribute to the background current beyond NDR.Comment: 8 pages 12 fig

    Latent HIV-1 Infection of Resting CD4+ T Cells in the Humanized Rag2-/-  c-/- Mouse

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    Persistent human immunodeficiency virus type 1 (HIV-1) infection of resting CD4+ T cells, unaffected by antiretroviral therapy (ART), provides a long-lived reservoir of HIV infection. Therapies that target this viral reservoir are needed to eradicate HIV-1 infection. A small-animal model that recapitulates HIV-1 latency in resting CD4+ T cells may accelerate drug discovery and allow the rational design of nonhuman primate (NHP) or human studies. We report that in humanized Rag2−/− γc−/− (hu-Rag2−/− γc−/−) mice, as in humans, resting CD4+ T cell infection (RCI) can be quantitated in pooled samples of circulating cells and tissue reservoirs (e.g., lymph node, spleen, bone marrow) following HIV-1 infection with the CCR5-tropic JR-CSF strain and suppression of viremia by ART. Replication-competent virus was recovered from pooled resting CD4+ T cells in 7 of 16 mice, with a median frequency of 8 (range, 2 to 12) infected cells per million T cells, demonstrating that HIV-1 infection can persist despite ART in the resting CD4+ T cell reservoir of hu-Rag2−/− γc−/− mice. This model will allow rapid preliminary assessments of novel eradication approaches and combinatorial strategies that may be challenging to perform in the NHP model or in humans, as well as a rigorous analysis of the effect of these interventions in specific anatomical compartments
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