323 research outputs found

    Human-based fibrillar nanocomposite hydrogels as bioinstructive matrices to tune stem cell behavior

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    The extracellular matrix (ECM)-biomimetic fibrillar structure of platelet lysate (PL) gels along with its enriched milieu of biomolecules has drawn significant interest in regenerative medicine applications. However, PL-based gels have poor structural stability which severely limits its performance as a bioinstructive biomaterial. Here, rod-shaped cellulose nanocrystals (CNC) are used as a novel approach to modulate the physical and biochemical microenvironment of PL gels enabling their effective use as injectable human-based cell scaffolds with a level of biomimicry that is difficult to recreate with synthetic biomaterials. The incorporation of CNC (0 to 0.61 wt.%) into the PL fibrillar network during the coagulation cascade leads to decreased fiber branching, increased interfiber porosity (from 66 to 83%) and modulate fiber (from 1.4 ± 0.7 to 27 ± 12 kPa) and bulk hydrogel (from 18 ± 4 to 1256 ± 82 Pa) mechanical properties. As result of these physicochemical alterations, nanocomposite PL hydrogels resist to the typical extensive clot retraction (from 76 ± 1 to 24 ± 3 at Day 7) and show favored retention of PL bioactive molecules. The feedback of these cues on the fate of human adipose-derived stem cells is evaluated, showing how it can be explored to modulate the commitment of encapsulated stem cells toward different genetic phenotypes without the need for additional external biological stimuli. These fibrillar nanocomposite hydrogels allow therefore to explore the outstanding biological properties of human-based PL as an efficient engineered ECM which can be tailored to trigger specific regenerative pathways in minimal invasive strategies.The authors thank the Hospital da Prelada (Porto, Portugal) for providing adipose tissue samples. The authors acknowledge the financial support from project Recognize (UTAP-ICDT/CTM-BIO/0023/2014), project NORTE-01-0145FEDER-000021 supported by the Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), the European Union Framework Programme for Research and Innovation HORIZON 2020, under the TEAMING Grant agreement No. 739572 – The Discoveries CTR EU, Forecast 668983, Marie Skłodowska-Curie grant agreement No. 706996 (PrinTendon) and CHEM2NATURE 692333; FCT/MCTES (Fundação para a Ciência e a Tecnologia/ Ministério da Ciência, Tecnologia, e Ensino Superior) and the Fundo Social Europeu através do Programa Operacional do Capital Humano (FSE/POCH) in the framework of PhD grant PD/59/2013 – PD/BD/113807/2015 for BBM, Post-Doc grant SFRH/BPD/112459/2015 for R.D.info:eu-repo/semantics/publishedVersio

    Study protocol for a pragmatic randomised controlled trial in general practice investigating the effectiveness of acupuncture against migraine

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    <p>Abstract</p> <p>Background</p> <p>Migraine is a chronic neurologic disease that can severely affect the patient's quality of life. Although in recent years many randomised studies have been carried out to investigate the effectiveness of acupuncture as a treatment for migraine, it remains a controversial issue. Our aim is to determine whether acupuncture, applied under real conditions of clinical practice in the area of primary healthcare, is more effective than conventional treatment.</p> <p>Methods/Design</p> <p>The design consists of a pragmatic multi-centre, three-armed randomised controlled trial, complemented with an economic evaluation of the results achieved, comparing the effectiveness of verum acupuncture with sham acupuncture, and with a control group receiving normal care only.</p> <p>Patients eligible for inclusion will be those presenting in general practice with migraine and for whom their General Practitioner (GP) is considering referral for acupuncture. Sampling will be by consecutive selection, and by randomised allocation to the three branches of the study, in a centralised way following a 1:1:1 distribution (verum acupuncture; sham acupuncture; conventional treatment). Secondly, one patient in three will be randomly selected from each of the acupuncture (verum or sham) groups for a brain perfusion study (by single photon emission tomography). The treatment with verum acupuncture will consist of 8 treatment sessions, once a week, at points selected individually by the acupuncturist. The sham acupuncture group will receive 8 sessions, one per week, with treatment being applied at non-acupuncture points in the dorsal and lumbar regions, using the minimal puncture technique. The control group will be given conventional treatment, as will the other two groups.</p> <p>Discussion</p> <p>This trial will contribute to available evidence on acupuncture for the treatment of migraine. The primary endpoint is the difference in the number of days with migraine among the three groups, between the baseline period (the 4 weeks prior to the start of treatment) and the period from weeks 9 to 12. As a secondary aspect, we shall record the index of laterality and the percentage of change in the mean count per pixel in each region of interest measured by the brain perfusion tomography, performed on a subsample of the patients within the real and sham acupuncture groups.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN98703707.</p

    Methylation Defect in Imprinted Genes Detected in Patients with an Albright's Hereditary Osteodystrophy Like Phenotype and Platelet Gs Hypofunction

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    Pseudohypoparathyroidism (PHP) indicates a group of heterogeneous disorders whose common feature is represented by impaired signaling of hormones that activate Gsalpha, encoded by the imprinted GNAS gene. PHP-Ib patients have isolated Parathormone (PTH) resistance and GNAS epigenetic defects while PHP-Ia cases present with hormone resistance and characteristic features jointly termed as Albright's Hereditary Osteodystrophy (AHO) due to maternally inherited GNAS mutations or similar epigenetic defects as found for PHP-Ib. Pseudopseudohypoparathyroidism (PPHP) patients with an AHO phenotype and no hormone resistance and progressive osseous heteroplasia (POH) cases have inactivating paternally inherited GNAS mutations.We here describe 17 subjects with an AHO-like phenotype that could be compatible with having PPHP but none of them carried Gsalpha mutations. Functional platelet studies however showed an obvious Gs hypofunction in the 13 patients that were available for testing. Methylation for the three differentially methylated GNAS regions was quantified via the Sequenom EpiTYPER. Patients showed significant hypermethylation of the XL amplicon compared to controls (36 ± 3 vs. 29 ± 3%; p<0.001); a pattern that is reversed to XL hypomethylation found in PHPIb. Interestingly, XL hypermethylation was associated with reduced XLalphaS protein levels in the patients' platelets. Methylation for NESP and ExonA/B was significantly different for some but not all patients, though most patients have site-specific CpG methylation abnormalities in these amplicons. Since some AHO features are present in other imprinting disorders, the methylation of IGF2, H19, SNURF and GRB10 was quantified. Surprisingly, significant IGF2 hypermethylation (20 ± 10 vs. 14 ± 7%; p<0.05) and SNURF hypomethylation (23 ± 6 vs. 32 6%; p<0.001) was found in patients vs. controls, while H19 and GRB10 methylation was normal.In conclusion, this is the first report of methylation defects including GNAS in patients with an AHO-like phenotype without endocrinological abnormalities. Additional studies are still needed to correlate the methylation defect with the clinical phenotype

    Sarilumab in patients admitted to hospital with severe or critical COVID-19: a randomised, double-blind, placebo-controlled, phase 3 trial

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    Background: Elevated proinflammatory cytokines are associated with greater COVID-19 severity. We aimed to assess safety and efficacy of sarilumab, an interleukin-6 receptor inhibitor, in patients with severe (requiring supplemental oxygen by nasal cannula or face mask) or critical (requiring greater supplemental oxygen, mechanical ventilation, or extracorporeal support) COVID-19. Methods: We did a 60-day, randomised, double-blind, placebo-controlled, multinational phase 3 trial at 45 hospitals in Argentina, Brazil, Canada, Chile, France, Germany, Israel, Italy, Japan, Russia, and Spain. We included adults (≥18 years) admitted to hospital with laboratory-confirmed SARS-CoV-2 infection and pneumonia, who required oxygen supplementation or intensive care. Patients were randomly assigned (2:2:1 with permuted blocks of five) to receive intravenous sarilumab 400 mg, sarilumab 200 mg, or placebo. Patients, care providers, outcome assessors, and investigators remained masked to assigned intervention throughout the course of the study. The primary endpoint was time to clinical improvement of two or more points (seven point scale ranging from 1 [death] to 7 [discharged from hospital]) in the modified intention-to-treat population. The key secondary endpoint was proportion of patients alive at day 29. Safety outcomes included adverse events and laboratory assessments. This study is registered with ClinicalTrials.gov, NCT04327388; EudraCT, 2020-001162-12; and WHO, U1111-1249-6021. Findings: Between March 28 and July 3, 2020, of 431 patients who were screened, 420 patients were randomly assigned and 416 received placebo (n=84 [20%]), sarilumab 200 mg (n=159 [38%]), or sarilumab 400 mg (n=173 [42%]). At day 29, no significant differences were seen in median time to an improvement of two or more points between placebo (12·0 days [95% CI 9·0 to 15·0]) and sarilumab 200 mg (10·0 days [9·0 to 12·0]; hazard ratio [HR] 1·03 [95% CI 0·75 to 1·40]; log-rank p=0·96) or sarilumab 400 mg (10·0 days [9·0 to 13·0]; HR 1·14 [95% CI 0·84 to 1·54]; log-rank p=0·34), or in proportions of patients alive (77 [92%] of 84 patients in the placebo group; 143 [90%] of 159 patients in the sarilumab 200 mg group; difference −1·7 [−9·3 to 5·8]; p=0·63 vs placebo; and 159 [92%] of 173 patients in the sarilumab 400 mg group; difference 0·2 [−6·9 to 7·4]; p=0·85 vs placebo). At day 29, there were numerical, non-significant survival differences between sarilumab 400 mg (88%) and placebo (79%; difference +8·9% [95% CI −7·7 to 25·5]; p=0·25) for patients who had critical disease. No unexpected safety signals were seen. The rates of treatment-emergent adverse events were 65% (55 of 84) in the placebo group, 65% (103 of 159) in the sarilumab 200 mg group, and 70% (121 of 173) in the sarilumab 400 mg group, and of those leading to death 11% (nine of 84) were in the placebo group, 11% (17 of 159) were in the sarilumab 200 mg group, and 10% (18 of 173) were in the sarilumab 400 mg group. Interpretation: This trial did not show efficacy of sarilumab in patients admitted to hospital with COVID-19 and receiving supplemental oxygen. Adequately powered trials of targeted immunomodulatory therapies assessing survival as a primary endpoint are suggested in patients with critical COVID-19. Funding: Sanofi and Regeneron Pharmaceuticals

    First observation and branching fraction measurement of the Λb0Dsp\Lambda_b^0\to D_s^- p decay

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    The first observation of the Λb0Dsp\Lambda_b^0\to D_s^- p decay is presented using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of s=13TeV{\sqrt{s}=13 \,\textrm{TeV}}, corresponding to a total integrated luminosity of 6fb16\,\textrm{fb}^{-1}. Using the Λb0Λc+π\Lambda_b^0\to\Lambda_c^+\pi^- decay as the normalisation mode, the branching fraction of the Λb0Dsp\Lambda_b^0\to D_s^- p decay is measured to be B(Λb0Dsp)=(12.6±0.5±0.3±1.2)×106{\mathcal{B}(\Lambda_b^0\to D_s^- p)=(12.6 \pm 0.5 \pm 0.3 \pm 1.2 )\times 10^{-6}}, where the first uncertainty is statistical, the second systematic and the third due to uncertainties in the branching fractions of the Λb0Λc+π\Lambda_b^0\to\Lambda_c^+\pi^-, DsKK+πD_s^- \to K^-K^+\pi^- and Λc+pKπ+\Lambda_c^+\to p K^- \pi^+ decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-038.html (LHCb public pages

    Study of charmonium decays to KS0KπK^0_S K \pi in the B(KS0Kπ)KB \to (K^0_S K \pi) K channels

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    A study of the B+KS0K+Kπ+B^+\to K^0_SK^+K^-\pi^+ and B+KS0K+K+πB^+\to K^0_SK^+K^+\pi^- decays is performed using proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV at the LHCb experiment. The KS0KπK^0_SK \pi invariant mass spectra from both decay modes reveal a rich content of charmonium resonances. New precise measurements of the ηc\eta_c and ηc(2S)\eta_c(2S) resonance parameters are performed and branching fraction measurements are obtained for B+B^+ decays to ηc\eta_c, J/ψJ/\psi, ηc(2S)\eta_c(2S) and χc1\chi_{c1} resonances. In particular, the first observation and branching fraction measurement of B+χc0K0π+B^+ \to \chi_{c0} K^0 \pi^+ is reported as well as first measurements of the B+K0K+Kπ+B^+\to K^0K^+K^-\pi^+ and B+K0K+K+πB^+\to K^0K^+K^+\pi^- branching fractions. Dalitz plot analyses of ηcKS0Kπ\eta_c \to K^0_SK\pi and ηc(2S)KS0Kπ\eta_c(2S) \to K^0_SK\pi decays are performed. A new measurement of the amplitude and phase of the KπK \pi SS-wave as functions of the KπK \pi mass is performed, together with measurements of the K0(1430)K^*_0(1430), K0(1950)K^*_0(1950) and a0(1700)a_0(1700) parameters. Finally, the branching fractions of χc1\chi_{c1} decays to KK^* resonances are also measured.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-051.html (LHCb public pages

    Measurement of lepton universality parameters in B+K++B^+\to K^+\ell^+\ell^- and B0K0+B^0\to K^{*0}\ell^+\ell^- decays

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    A simultaneous analysis of the B+K++B^+\to K^+\ell^+\ell^- and B0K0+B^0\to K^{*0}\ell^+\ell^- decays is performed to test muon-electron universality in two ranges of the square of the dilepton invariant mass, q2q^2. The measurement uses a sample of beauty meson decays produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 99 fb1\text{fb}^{-1}. A sequence of multivariate selections and strict particle identification requirements produce a higher signal purity and a better statistical sensitivity per unit luminosity than previous LHCb lepton universality tests using the same decay modes. Residual backgrounds due to misidentified hadronic decays are studied using data and included in the fit model. Each of the four lepton universality measurements reported is either the first in the given q2q^2 interval or supersedes previous LHCb measurements. The results are compatible with the predictions of the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-045.html (LHCb public pages

    First observation of the B+Ds+DsK+B^+ \rightarrow D_s^+ D_s^- K^+ decay

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    The B+Ds+DsK+B^+ \rightarrow D_s^+ D_s^- K^+ decay is observed for the first time using proton-proton collision data collected by the LHCb detector at centre-of-mass energies of 77, 88 and 13TeV13\, \text{TeV}, corresponding to an integrated luminosity of 9fb19\,\text{fb}^{-1}. Its branching fraction relative to that of the B+D+DK+B^{+} \rightarrow D^{+} D^{-} K^{+} decay is measured to be B(B+Ds+DsK+)B(B+D+DK+)=0.525±0.033±0.027±0.034,\frac{B\left(B^{+} \rightarrow D_s^{+} D_s^{-} K^{+}\right)}{B\left(B^{+} \rightarrow D^{+} D^{-} K^{+}\right)}=0.525 \pm 0.033 \pm 0.027 \pm 0.034, where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the Ds±KK±π±D_s^{\pm} \rightarrow K^{\mp} K^{\pm} \pi^{\pm} and D±Kπ±π±D^{\pm} \rightarrow K^{\mp} \pi^{\pm} \pi^{\pm} decays. This measurement fills an experimental gap in the knowledge of the family of Cabibbo-favoured bˉcˉcsˉ\bar{b} \rightarrow \bar{c} c \bar{s} transitions and opens the path for unique studies of spectroscopy in future.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-019.html (LHCb public pages
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