654 research outputs found

    Labeling and purification studies on cancer targeting DOTA-TATE labeled with radiolanthanides

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    Abstract only availableMolecular imaging and targeted radiotherapy are emerging fields for cancer treatment. DOTA-Tyr (3)-Thr(9)-octreotate (DOTA-TATE) is used for peptide receptor-mediated radionuclide therapy (PRMRT) in neuroendocrine tumours. These biomolecules can be radiolabeled with an appropriated radioisotope to produce radiopharmaceuticals for diagnostic and therapeutic applications. The DOTA-TATE molecule is comprised of a bifunctional chelate (DOTA) that is capable of stably binding a radiolanthanide as well as being covalently attached to a targeting biomolecule (e.g.,octreotate). Among the radiolanthanides, Ho-166, Tb-161 and Lu-177, that were used to label the peptide, Lu-177 was used to obtain optimum conditions. Direct neutron capture on Lu-176 produces Lu-177. The indirect production of Lu-177 proceeds by neutron capture on Yb-176 producing Yb-177, which beta decays to Lu-177. Chromatographic separation yields high specific activity Lu-177 that minimizes the presence of cold Lu-176. Lanthanides have similar chemical properties that allow further studies to apply similar conditions as those developed for Lu-177. In addition, longevity of half-life of Lu-177 enables longer periods of dose delivery to targeted tumors. This research focused on identifying appropriate buffer solutions and volumes that could neutralize the acidic radioisotope to appropriate pH levels to label the peptide in high yield. The sample was purified from the unlabeled peptide by using HPLC separations methods and adding stabilizing agents (ascorbic and gentisic acid) to prevent radiolysis of the radiolabeled peptide. The results for the labeled peptide with various radioisotopes shows that 0.4 M NH4OAc, 0.4 M NaOAc, and 0.01 M HEPES buffer solution in 500 µL yields 99% labeling at pH ranging from 6.0 to 7.5. The labeled ligand at equimolar ratio with the metal yields 3 mCi/µg of the ligand, whereas as high specific activity sample can label up to 6.68 mCi/µg of the ligand. Carrier free Lu-177-DOTA-TATE was labeled using 0.01 M HEPES buffer at pH 6.0 and remains stable after using ascorbic acid; gentisic acid shows interference on HPLC which may cause some purification problems. (Ho- holmium, Tb- terbium Lu- lutetium)U.S. Dept. of Energy Innovations in Nuclear Infrastructure and Education Summer MURR Undergraduate Research Scholarshi

    Effects of accelerated versus standard care surgery on the risk of acute kidney injury in patients with a hip fracture: a substudy protocol of the hip fracture accelerated surgical treatment and care track (HIP ATTACK) international randomised controlled trial

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    Accelerated surgery; Acute kidney injury; Hip fractureCirugía acelerada; Lesión renal aguda; Fractura de caderaCirurgia accelerada; Lesions renals agudes; Fractura de malucIntroduction: Inflammation, dehydration, hypotension and bleeding may all contribute to the development of acute kidney injury (AKI). Accelerated surgery after a hip fracture can decrease the exposure time to such contributors and may reduce the risk of AKI. Methods and analysis: Hip fracture Accelerated surgical TreaTment And Care tracK (HIP ATTACK) is a multicentre, international, parallel-group randomised controlled trial (RCT). Patients who suffer a hip fracture are randomly allocated to either accelerated medical assessment and surgical repair with a goal of surgery within 6 hours of diagnosis or standard care where a repair typically occurs 24 to 48 hours after diagnosis. The primary outcome of this substudy is the development of AKI within 7 days of randomisation. We anticipate at least 1998 patients will participate in this substudy. Ethics and dissemination: We obtained ethics approval for additional serum creatinine recordings in consecutive patients enrolled at 70 participating centres. All patients provide consent before randomisation. We anticipate reporting substudy results by 2021. Trial registration number: NCT02027896; Pre-results.This work was supported by the following grants: Canadian Institute of Health and Research (CIHR) Foundation Award, CIHR’s Strategy for Patient Oriented Research (SPOR), through the Ontario SPOR Support Unit, which is supported by the CIHR and the Province of Ontario, as well as the Ontario Ministry of Health and Long-Term Care, and a grant from Smith & Nephew to recruit 300 patients in Spain. Grants to support this substudy were provided by the Department of Medicine at Western University. Dr Devereaux was supported by a Tier 1 Canada Research Chair in Perioperative Medicine. Dr Amit Garg was supported by the Dr Adam Linton Chair in Kidney Health Analytics and a CIHR Clinician Investigator Award

    Genome-wide association studies for methane production in dairy cattle

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    © 2019 by the authors. Licensee MDPI, Basel, Switzerland. Genomic selection has been proposed for the mitigation of methane (CH4) emissions by cattle because there is considerable variability in CH4 emissions between individuals fed on the same diet. The genome-wide association study (GWAS) represents an important tool for the detection of candidate genes, haplotypes or single nucleotide polymorphisms (SNP) markers related to characteristics of economic interest. The present study included information for 280 cows in three dairy production systems in Mexico: 1) Dual Purpose (n = 100), 2) Specialized Tropical Dairy (n = 76), 3) Familiar Production System (n = 104). Concentrations of CH4 in a breath of individual cows at the time of milking (MEIm) were estimated through a system of infrared sensors. After quality control analyses, 21,958 SNPs were included. Associations of markers were made using a linear regression model, corrected with principal component analyses. In total, 46 SNPs were identified as significant for CH4 production. Several SNPs associated with CH4 production were found at regions previously described for quantitative trait loci of composition characteristics of meat, milk fatty acids and characteristics related to feed intake. It was concluded that the SNPs identified could be used in genomic selection programs in developing countries and combined with other datasets for global selection

    S100A8 & S100A9: alarmin mediated inflammation in tendinopathy

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    Alarmins S100A8 and S100A9 are endogenous molecules released in response to environmental triggers and cellular damage. They are constitutively expressed in immune cells such as monocytes and neutrophils and their expression is upregulated under inflammatory conditions. The molecular mechanisms that regulate inflammatory pathways in tendinopathy are largely unknown therefore identifying early immune effectors is essential to understanding the pathology. Based on our previous investigations highlighting tendinopathy as an alarmin mediated pathology we sought evidence of S100A8 & A9 expression in a human model of tendinopathy and thereafter, to explore mechanisms whereby S100 proteins may regulate release of inflammatory mediators and matrix synthesis in human tenocytes. Immunohistochemistry and quantitative RT-PCR showed S100A8 & A9 expression was significantly upregulated in tendinopathic tissue compared with control. Furthermore, treating primary human tenocytes with exogenous S100A8 & A9 significantly increased protein release of IL-6, IL-8, CCL2, CCL20 and CXCL10; however, no alterations in genes associated with matrix remodelling were observed at a transcript level. We propose S100A8 & A9 participate in early pathology by modulating the stromal microenvironment and influencing the inflammatory profile observed in tendinopathy. S100A8 and S100A9 may participate in a positive feedback mechanism involving enhanced leukocyte recruitment and release of pro-inflammatory cytokines from tenocytes that perpetuates the inflammatory response within the tendon in the early stages of disease

    A predictive model and risk factors for case fatality of covid-19

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    This study aimed to create an individualized analysis model of the risk of intensive care unit (ICU) admission or death for coronavirus disease 2019 (COVID-19) patients as a tool for the rapid clinical management of hospitalized patients in order to achieve a resilience of medical resources. This is an observational, analytical, retrospective cohort study with longitudinal follow-up. Data were collected from the medical records of 3489 patients diagnosed with COVID-19 using RT-qPCR in the period of highest community transmission recorded in Europe to date: February–June 2020. The study was carried out in in two health areas of hospital care in the Madrid region: the central area of the Madrid capital (Hospitales de Madrid del Grupo HM Hospitales (CH-HM), n = 1931) and the metropolitan area of Madrid (Hospital Universitario Príncipe de Asturias (MH-HUPA) n = 1558). By using a regression model, we observed how the different patient variables had unequal importance. Among all the analyzed variables, basal oxygen saturation was found to have the highest relative importance with a value of 20.3%, followed by age (17.7%), lymphocyte/leukocyte ratio (14.4%), CRP value (12.5%), comorbidities (12.5%), and leukocyte count (8.9%). Three levels of risk of ICU/death were established: low-risk level (20%). At the high-risk level, 13% needed ICU admission, 29% died, and 37% had an ICU–death outcome. This predictive model allowed us to individualize the risk for worse outcome for hospitalized patients affected by COVID-19

    Correcting non cephalic presentation with moxibustion: study protocol for a multi-centre randomised controlled trial in general practice

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    <p>Abstract</p> <p>Background</p> <p>Non cephalic presentation in childbirth involves various risks to both the mother and the foetus. The incidence in Spain is 3.8% of all full-term pregnancies. The most common technique used to end the gestation in cases of non cephalic presentation is that of caesarian section, and although it provokes a lower rate of morbi-mortality than does vaginal delivery in such situations, there remains the possibility of traumatic injury to the foetal head and neck, while maternal morbidity is also increased. The application of heat (moxibustion) to an acupuncture point, in order to correct non cephalic presentation, has been practised in China since ancient times, but as yet there is insufficient evidence of its real effectiveness.</p> <p>Methods/Design</p> <p>The experimental design consists of a multi-centre randomised controlled trial with three parallel arms, used to compare real moxibustion, sham moxibustion and the natural course of events, among pregnant women with a non cephalic presentation and a gestational duration of 33–35 weeks (estimated by echography). The participants in the trial will be blinded to both interventions. The results obtained will be analyzed by professionals, blinded with respect to the allocation to the different types of intervention. In addition, we intend to carry out a economic analysis.</p> <p>Discussion</p> <p>This trial will contribute to the development of evidence concerning moxibustion in the correction of non cephalic presentations. The primary outcome variable is the proportion of cephalic presentations at term. As secondary outcomes, we will evaluate the proportion of cephalic presentations at week 38 of gestation, determined by echography, together with the safety of the technique, the specificity of moxibustion and the control of the blinding process.</p> <p>This study has been funded by the Health Ministry of the Andalusian Regional Government.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN10634508.</p

    Vancomycin wrap for anterior cruciate ligament surgery

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    Background: The use of the vancomycin wrap to pretreat the hamstring graft in anterior cruciate ligament reconstruction (ACLR) has grown in popularity since it was first described in 2012 and has significantly reduced rates of postoperative infection. However, it remains unknown if this antibiotic treatment affects the molecular composition of the graft. Purpose: To establish whether treatment with vancomycin at 5 mg/mL, the most commonly used concentration, alters the molecular function of the hamstring graft in ACLR. Study Design: Controlled laboratory study. Methods: Surplus hamstring tendon collected after routine ACLR surgery was used for in vitro cell culture and ex vivo tissue experiments. Vancomycin was used at 5 mg/mL in RPMI or saline diluent to treat cells and tendon tissue, respectively, with diluent control conditions. Cell viability at 30, 60, and 120 minutes was assessed via colorimetric viability assay. Tendon cells treated with control and experimental conditions for 1 hour was evaluated using semiquantitative reverse transcription analysis, immunohistochemistry staining, and protein quantitation via enzyme-linked immunosorbent assay for changes in apoptotic, matrix, and inflammatory gene and protein expression. Results: Vancomycin treatment at 5 mg/mL significantly reduced tenocyte viability in vitro after 60 minutes of treatment (P &lt; .05); however, this was not sustained at 120 minutes. Vancomycin-treated tendon tissue showed no significant increase in apoptotic gene expression, or apoptotic protein levels in tissue or supernatant, ex vivo. Vancomycin was associated with a reduction in inflammatory proteins from treated tendon supernatants (IL-6; P &lt; .05). Conclusion: Vancomycin did not significantly alter the molecular structure of the hamstring graft. Reductions in matrix protein and inflammatory cytokine release point to a potential beneficial effect of vancomycin in generating a homeostatic environment. Clinical Relevance: Vancomycin ACL wrap does not alter the molecular structure of the ACL hamstring graft and may improve graft integrity

    Simulating magnetized neutron stars with discontinuous Galerkin methods

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    Discontinuous Galerkin methods are popular because they can achieve high order where the solution is smooth, because they can capture shocks while needing only nearest-neighbor communication, and because they are relatively easy to formulate on complex meshes. We perform a detailed comparison of various limiting strategies presented in the literature applied to the equations of general relativistic magnetohydrodynamics. We compare the standard minmod/ΛΠN\Lambda\Pi^N limiter, the hierarchical limiter of Krivodonova, the simple WENO limiter, the HWENO limiter, and a discontinuous Galerkin-finite-difference hybrid method. The ultimate goal is to understand what limiting strategies are able to robustly simulate magnetized TOV stars without any fine-tuning of parameters. Among the limiters explored here, the only limiting strategy we can endorse is a discontinuous Galerkin-finite-difference hybrid method

    Zero-Knowledge Arguments for Matrix-Vector Relations and Lattice-Based Group Encryption

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    International audienceGroup encryption (GE) is the natural encryption analogue of group signatures in that it allows verifiably encrypting messages for some anonymous member of a group while providing evidence that the receiver is a properly certified group member. Should the need arise, an opening authority is capable of identifying the receiver of any ciphertext. As introduced by Kiayias, Tsiounis and Yung (Asiacrypt'07), GE is motivated by applications in the context of oblivious retriever storage systems, anonymous third parties and hierarchical group signatures. This paper provides the first realization of group encryption under lattice assumptions. Our construction is proved secure in the standard model (assuming interaction in the proving phase) under the Learning-With-Errors (LWE) and Short-Integer-Solution (SIS) assumptions. As a crucial component of our system, we describe a new zero-knowledge argument system allowing to demonstrate that a given ciphertext is a valid encryption under some hidden but certified public key, which incurs to prove quadratic statements about LWE relations. Specifically, our protocol allows arguing knowledge of witnesses consisting of X ∈ Z m×n q , s ∈ Z n q and a small-norm e ∈ Z m which underlie a public vector b = X · s + e ∈ Z m q while simultaneously proving that the matrix X ∈ Z m×n q has been correctly certified. We believe our proof system to be useful in other applications involving zero-knowledge proofs in the lattice setting

    The spectrum and clinical impact of epigenetic modifier mutations in myeloma

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    Epigenetic dysregulation is known to be an important contributor to myeloma pathogenesis but, unlike in other B cell malignancies, the full spectrum of somatic mutations in epigenetic modifiers has not been previously reported. We sought to address this using results from whole-exome sequencing in the context of a large prospective clinical trial of newly diagnosed patients and targeted sequencing in a cohort of previously treated patients for comparison.Whole-exome sequencing analysis of 463 presenting myeloma cases entered in the UK NCRI Myeloma XI study and targeted sequencing analysis of 156 previously treated cases from the University of Arkansas for Medical Sciences. We correlated the presence of mutations with clinical outcome from diagnosis and compared the mutations found at diagnosis with later stages of disease.In diagnostic myeloma patient samples we identify significant mutations in genes encoding the histone 1 linker protein, previously identified in other B-cell malignancies. Our data suggest an adverse prognostic impact from the presence of lesions in genes encoding DNA methylation modifiers and the histone demethylase KDM6A/UTX. The frequency of mutations in epigenetic modifiers appears to increase following treatment most notably in genes encoding histone methyltransferases and DNA methylation modifiers.Numerous mutations identified raise the possibility of targeted treatment strategies for patients either at diagnosis or relapse supporting the use of sequencing-based diagnostics in myeloma to help guide therapy as more epigenetic targeted agents become available
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