183,573 results match your criteria procedures protocols


Exploring miniaturized sample preparation approaches combined with LC-QToF-MS for the analysis of sulfonamide antibiotic residues in meat- and/or egg-based baby foods.

Food Chem 2021 Jul 14;366:130587. Epub 2021 Jul 14.

Department of Food Science, School of Food Engineering, University of Campinas (UNICAMP), Rua Monteiro Lobato, 80, CEP 13083-862, Campinas, SP, Brazil.

Miniaturized and simplified sample preparation methods with reduced consumption of chemicals and non-halogenated solvents are presented for the determination of 12 sulfonamides in baby foods. Hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was used for the identification and quantification of the compounds based on the acquisition of full spectrum at high resolution with accurate mass for precursor and its fragment ions. Three miniaturized protocols based on QuEChERS, salting-out assisted liquid-liquid extraction or low-temperature cleanup were evaluated regarding the extraction efficiency and removal capability of matrix co-extractives. Read More

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Standard therapy of Mycobacterium avium complex pulmonary disease shows limited efficacy in an open source hollow fiber system that simulates human plasma and epithelial lining fluid pharmacokinetics.

Clin Microbiol Infect 2021 Jul 28. Epub 2021 Jul 28.

Radboudumc Center for Infectious Diseases, Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, the Netherlands.

Objectives: Mycobacterium avium complex (MAC) bacteria can cause chronic pulmonary disease (PD). Current treatment regimens of azithromycin, ethambutol and rifampicin have culture conversion rates of around 65%. Dynamic, pre-clinical models to assess the efficacy of treatment regimens are important to guide clinical trial development. Read More

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The toll of COVID-19 on African children: A descriptive analysis on the COVID-19-related morbidity and mortality among the pediatric population in Sub-Saharan Africa.

Int J Infect Dis 2021 Jul 28. Epub 2021 Jul 28.

WHO Regional Office for Africa, Epidemic Preparedness and Response Programme, Cité du Djoué, P.O. Box 06, Brazzaville, Republic du Congo. Electronic address:

Introduction: Few data on the COVID-19 epidemiological characteristics among the pediatric population in Africa exists. This paper examines the age and sex distribution of the morbidity and mortality rate in children with COVID-19 and compares it to the adult population within 15 Sub-Saharan African countries.

Methods: A merge line listing dataset shared by countries within the Regional Office for Africa was analyzed. Read More

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Optimisation of CT protocols in PET-CT across different scanner models using different automatic exposure control methods and iterative reconstruction algorithms.

EJNMMI Phys 2021 Jul 31;8(1):58. Epub 2021 Jul 31.

King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK.

Background: A significant proportion of the radiation dose from a PET-CT examination is dependent on the CT protocol, which should be optimised for clinical purposes. Matching protocols on different scanners within an imaging centre is important for the consistency of image quality and dose. This paper describes our experience translating low-dose CT protocols between scanner models utilising different automatic exposure control (AEC) methods and reconstruction algorithms. Read More

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Simultaneous LC-MS/MS bioanalysis of alkaloids, terpenoids, and flavonoids in rat plasma through salting-out-assisted liquid-liquid extraction after oral administration of extract from Tetradium ruticarpum and Glycyrrhiza uralensis: a sample preparation strategy to broaden analyte coverage of herbal medicines.

Anal Bioanal Chem 2021 Jul 31. Epub 2021 Jul 31.

Institute of Chinese Materia Medica, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai Key Laboratory of Compound Chinese Medicines, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China.

Herbal medicines have historically been practiced in combinatorial way, which achieves therapeutic efficacy by integrative effects of multi-components. Thus, the accurate and precise measurement of multi bioactive components in matrices is inalienable to understanding the metabolism and disposition of herbal medicines. In this study, aiming to provide a strategy that improves analyte coverage, evaluation of six protocols employing sample pretreatment methods- protein precipitation (PPT), liquid-liquid extraction (LLE), sugaring-out-assisted liquid-liquid extraction (SULLE), and salting-out-assisted liquid-liquid extraction (SALLE)- was performed by LC-MS/MS using rat plasma and a mixture of alkaloid (evodiamine, rutaecarpine, dehydroevodiamine), terpenoid (limonin, rutaevin, obacunone), and flavonoid (liquiritin, isoliquiritin, liquiritigenin) standards isolated from Tetradium ruticarpum and Glycyrrhiza uralensis. Read More

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Do carers and comforters require lead aprons during general radiographic examinations?

J Med Imaging Radiat Oncol 2021 Jul 31. Epub 2021 Jul 31.

Medical Imaging Department, The Royal Children's Hospital, Melbourne, Victoria, Australia.

Introduction: Carers and comforters frequently remain with children during paediatric general radiographic examinations. As well as improving the likelihood of overall success of the procedure, this can be important for minimising stress and anxiety of the child. Wearing lead aprons can contribute to additional stress and anxiety about the procedure for both carer and child, specifically due to radiation risk. Read More

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Characterizing the relationships between tertiary and community cancer providers: Results from a survey of medical oncologists in Southern California.

Cancer Med 2021 Jul 31. Epub 2021 Jul 31.

Department of Medical Oncology & Experimental Therapeutics, City of Hope Comprehensive Cancer Center, Duarte, CA, USA.

Background: Tertiary cancer centers offer clinical expertise and multi-modal approaches to treatment alongside the integration of research protocols. Nevertheless, most patients receive their cancer care at community practices. A better understanding of the relationships between tertiary and community practice environments may enhance collaborations and advance patient care. Read More

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Multicolor Bioluminescence Imaging of Subcellular Structures and Multicolor Calcium Imaging in Single Living Cells.

Methods Mol Biol 2021 ;2350:229-237

SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Osaka, Ibaraki, Japan.

The recent development of the bright luciferase NanoLuc (Nluc) has greatly improved the sensitivity of bioluminescence imaging, enabling real-time cellular imaging with high spatial resolution. However, the limited color variants of Nluc have restricted its wider application to multicolor imaging of biological phenomena. To address this issue, we developed five new spectral variants of the bright bioluminescent protein with emissions across the visible spectrum. Read More

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January 2021

Out-of-Phase Imaging after Optical Modulation (OPIOM) for Multiplexed Fluorescence Imaging Under Adverse Optical Conditions.

Methods Mol Biol 2021 ;2350:191-227

PASTEUR, Département de Chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, Paris, France.

Fluorescence imaging has become a powerful tool for observations in biology. Yet it has also encountered limitations to overcome optical interferences of ambient light, autofluorescence, and spectrally interfering fluorophores. In this account, we first examine the current approaches which address these limitations. Read More

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January 2021

Isolation of Adult Mouse Cardiomyocytes Using Langendorff Perfusion Apparatus.

Methods Mol Biol 2021 ;2319:143-152

Department of Medical Physiology, Texas A&M University College of Medicine, Brain, TX, USA.

Heart disease is one of the leading causes of death in the United States. Isolation and culture adult cardiomyocytes are important for studying cardiomyocyte contractility, heart hypertrophy, and cardiac failure. In contrast to neonatal cardiomyocyte isolation, adult mice cardiomyocytes isolation is challenging due to firm connections among cardiomyocytes through intercalated discs. Read More

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January 2021

Visualization of Retinal Blood Vessels.

Methods Mol Biol 2021 ;2319:111-117

Department of Medical Physiology, College of Medicine, Texas A&M University Heath Science Center, Bryan, TX, USA.

The retina offers a unique opportunity to directly visualize blood vessels in vivo noninvasively. Over the past few decades, several new imaging techniques have been adapted to study the retinal vasculature in the laboratory in animal models and in the clinic in human subjects. High-contrast, finely detailed fundus images can be acquired by confocal scanning laser ophthalmoscopy (cSLO). Read More

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January 2021

Laser-Induced Choroidal Neovascularization in Rats.

Methods Mol Biol 2021 ;2319:77-85

Department of Medical Physiology, College of Medicine, Texas A&M University Heath Science Center, Bryan, TX, USA.

The laser-induced choroidal neovascularization (CNV) model has been widely used for research on wet age-related macular degeneration (wet-AMD) and other ocular neovascular diseases. In this model, the Bruch membrane is perforated by laser injury, resulting in neovascularization formed from the choroidal capillaries. It has become a standard method to evaluate the effect of different treatments on CNV progression in preclinical studies. Read More

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January 2021

Optimizing the Differentiation of Cardiomyocytes from Human Induced Pluripotent-Derived Stem Cells.

Methods Mol Biol 2021 ;2319:51-60

Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA.

Cardiovascular disease is a worldwide health issue that affects millions of lives every year, and thus, researchers are in need of high-throughput model systems with which to investigate mechanisms of disease and to develop and test potential therapies. The use of human-derived induced pluripotent stem cells (iPSCs) differentiated into cardiomyocytes aims to address this need. While cardiac differentiation protocols have been established previously in iPSCs, optimization of cardiac differentiation remains crucial to obtaining high quality cardiomyocytes for future experimental analyses. Read More

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January 2021

Preparation of Neonatal Rat Papillary Muscles for Contractile Studies.

Methods Mol Biol 2021 ;2319:31-44

Department of Medical Physiology, College of Medicine, Texas A&M University, Bryan, TX, USA.

Isolated cardiac tissue allows investigators to study mechanisms underlying normal and pathological conditions, which would otherwise be difficult or impossible to perform in vivo. In contrast to ventricular muscle strip preparations, papillary muscles can be prepared without severely damaging the muscle tissue. In this preparation, the isolated papillary muscle is fixed in an environmentally controlled organ bath chamber and electrically stimulated. Read More

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January 2021

Neuropsychological Assessment in Autism Spectrum Disorder.

Curr Psychiatry Rep 2021 Jul 30;23(10):63. Epub 2021 Jul 30.

Seaver Autism Center for Research and Treatment, Icahn School of Medicine At Mount Sinai, New York, NY, USA.

Purpose Of Review: Neuropsychological assessment involves the comprehensive evaluation of intellectual, attentional, executive, social-cognitive, language, and motor functioning. Such assessments are used to characterize areas of strength and weakness, inform differential diagnosis, guide treatment planning, and evaluate change over time. Individuals with autism spectrum disorder (ASD) present with varied clinical presentations, which can make the design of testing batteries and subsequent interpretation of results challenging. Read More

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Single-direction diffusion-weighted imaging may be a simple complementary sequence for evaluating fetal corpus callosum.

Eur Radiol 2021 Jul 30. Epub 2021 Jul 30.

Department of Radiology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.

Objectives: To explore the feasibility of single-direction diffusion-weighted imaging (DWI) for assessing the fetal corpus callosum (CC).

Methods: This prospective study included 67 fetuses with normal CC and 35 fetuses suspected with agenesis of the corpus callosum (ACC). The MR protocols included HASTE, TrueFISP, and single-direction DWI. Read More

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Site-specific Umpolung amidation of carboxylic acids via triplet synergistic catalysis.

Nat Commun 2021 Jul 30;12(1):4637. Epub 2021 Jul 30.

State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.

Development of catalytic amide bond-forming methods is important because they could potentially address the existing limitations of classical methods using superstoichiometric activating reagents. In this paper, we disclose an Umpolung amidation reaction of carboxylic acids with nitroarenes and nitroalkanes enabled by the triplet synergistic catalysis of FeI, P(V)/P(III) and photoredox catalysis, which avoids the production of byproducts from stoichiometric coupling reagents. A wide range of carboxylic acids, including aliphatic, aromatic and alkenyl acids participate smoothly in such reactions, generating structurally diverse amides in good yields (86 examples, up to 97% yield). Read More

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Clinical utility of peptide microarrays in the serodiagnosis of neglected tropical diseases in sub-Saharan Africa: protocol for a diagnostic test accuracy systematic review.

BMJ Open 2021 Jul 30;11(7):e042279. Epub 2021 Jul 30.

Biotechnology and Biochemistry, University of Zimbabwe Faculty of Science, Harare, Zimbabwe.

Introduction: Neglected tropical diseases tend to cluster in the same poor populations and, to make progress with their control, they will have to be dealt with in an integrated manner. Peptide microarrays may be a solution to these problems, where diagnosis for co-infection can be detected simultaneously using the one tool. A meta-analysis using hierarchical models will be performed to assess the diagnostic accuracy of peptide microarrays for detecting schistosomiasis ( and ), soil-transmitted helminths (, and ), trachoma (), lymphatic filariasis () and onchocerciasis () in people residing in sub-Saharan Africa. Read More

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Preoperative weight loss is linked to improved mortality and leaks following elective bariatric surgery: an analysis of 548,597 patients from 2015-2018.

Surg Obes Relat Dis 2021 Jul 7. Epub 2021 Jul 7.

Department of Surgery, University of Alberta, Edmonton, Alberta, Canada.

Background: The effects of preoperative weight loss on bariatric surgery outcomes are still unclear, despite the practice being adopted by bariatric centers worldwide. Ongoing studies are needed for routine adoption of this practice given the multiple issues patients face with following difficult preoperative weight loss protocols.

Objectives: The aim of this study was to characterize the prevalence of preoperative weight loss and evaluate its impact on outcomes following elective bariatric surgery. Read More

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Characterizing Baclofen Withdrawal: A National Survey of Physician Experience.

Pediatr Neurol 2021 Jul 27. Epub 2021 Jul 27.

Center for Orphan Drug Research, Experimental & Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota.

Objective: We studied physicians' opinions and experiences concerning clinical concerns, perceived severity, occurrence, and management of baclofen withdrawal due to abrupt discontinuation.

Methods: A nationwide 26-question electronic survey was distributed via e-mail to physicians (N = 952) representing varying specialties who manage spasticity with baclofen. A total of 110 physicians provided responses to the survey (response rate = 11. Read More

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Prevalence and risk factors for acute stress disorder and posttraumatic stress disorder after burn injury.

Am J Surg 2021 Jul 26. Epub 2021 Jul 26.

Firefighters' Burn and Surgical Research Laboratory, MedStar Health Research Institute, Washington, DC, USA; The Burn Center, Department of Surgery, MedStar Washington Hospital Center, USA; Department of Surgery, Georgetown University School of Medicine, Washington, DC, USA. Electronic address:

Background: Psychological consequences of burn injury can be profound. Acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) are known sequelae, but routine identification is challenging. This study aims to identify patient characteristics associated with outpatient positive screens. Read More

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Pre-cementation procedures' effect on dental zirconias with different yttria content.

Dent Mater 2021 Jul 27. Epub 2021 Jul 27.

NIOM, Nordic Institute of Dental Materials, Oslo, Norway.

Objectve: Several pre-cementation procedures have been advocated to enhance adhesion between zirconia and resin-based cement. There is, however, limited documentation on how these pre-treatments affect the strength of zirconia crowns as most tests are performed on discs or bars. The aim was to assess the effect of pre-cementation procedures on fracture mode, fracture strength and cement retention on zirconia. Read More

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The effect of timing of enteral nutrition support on feeding outcomes and dysphagia in patients with head and neck cancer undergoing radiotherapy or chemoradiotherapy: A systematic review.

Clin Nutr ESPEN 2021 Aug 3;44:96-104. Epub 2021 Jun 3.

School of Human Movement and Nutrition Sciences, University of Queensland, Queensland, Australia. Electronic address:

Background & Aims: Patients with head and neck cancer (HNC) often require enteral nutrition (EN). This systematic review reports the effect of EN timing in patients with HNC undergoing curative-intent and definitive or adjuvant radiotherapy or chemoradiotherapy on tube feeding duration, tube-related complications and dysphagia.

Methods: Randomised controlled trials (RCTs) published between January 2015-April 2020 were obtained from Medline, CINAHL and Embase. Read More

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Distinct approaches to language pathway tractography: comparison of anatomy-based, repetitive navigated transcranial magnetic stimulation (rTMS)-based, and rTMS-enhanced diffusion tensor imaging-fiber tracking.

J Neurosurg 2021 Jul 30:1-12. Epub 2021 Jul 30.

Departments of1Neurosurgery and.

Objective: Visualization of subcortical language pathways by means of diffusion tensor imaging-fiber tracking (DTI-FT) is evolving as an important tool for surgical planning and decision making in patients with language-suspect brain tumors. Repetitive navigated transcranial magnetic stimulation (rTMS) cortical language mapping noninvasively provides additional functional information. Efforts to incorporate rTMS data into DTI-FT are promising, but the lack of established protocols makes it hard to assess clinical utility. Read More

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A meta-epidemiological study found lack of transparency and poor reporting of disproportionality analyses for signal detection in pharmacovigilance databases.

J Clin Epidemiol 2021 Jul 27. Epub 2021 Jul 27.

Pharmacovigilance Unit, Grenoble Alpes University Hospital, F-38000 Grenoble, France; HP2 Laboratory, INSERM U1300, Univ. Grenoble Alpes, F-38000 Grenoble, France.

Objective: To review and appraise methods and reporting characteristics of pharmacovigilance disproportionality analyses.

Study Design And Setting: We randomly selected 100 disproportionality analyses indexed in Medline found during a systematic literature search. We then extracted and synthetized methodological and reporting characteristics using 7 key items: 1) title transparency; 2) protocol pre-registration; 3) date of data extraction and analysis; 4) outcome, population, exposure and comparator definitions; 5) adjustment and stratification of results; 6) method and threshold for signal detection; 7) secondary and sensitivity analyses. Read More

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Experimental measurement-device-independent quantum key distribution with the double-scanning method.

Opt Lett 2021 Aug;46(15):3729-3732

The measurement-device-independent quantum key distribution (MDI-QKD) can be immune to all detector side-channel attacks. Moreover, it can be easily implemented combining with the matured decoy-state methods under current technology. It, thus, seems a very promising candidate in practical implementation of quantum communications. Read More

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30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries.

Obes Surg 2021 Jul 30. Epub 2021 Jul 30.

Bariatric Unit, South Tyneside and Sunderland NHS Trust, Sunderland, UK.

Background: There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2019 (COVID-19) pandemic and to determine the efficacy of perioperative COVID-19 protective strategies on postoperative symptomatic COVID-19 rates. Read More

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Hospital antenatal admissions for threatened preterm labor: how long should we be "observing"?

Arch Gynecol Obstet 2021 Jul 30. Epub 2021 Jul 30.

Department of Obstetrics and Gynecology, Jewish General Hospital, McGill University, Montreal, Canada.

Purpose: We sought to describe temporal trends in hospital admissions for threatened preterm labor (TPTL) and to examine hospital admission duration among women delivered or discharged undelivered.

Methods: We carried out a cohort study on all TPTL admissions among pregnancies with a live singleton fetus and intact membranes between 1999 and 2015 using the United States' Healthcare Cost and Utilization Project-Nationwide Inpatient Sample. ICD-9 codes were used to identify women with TPTL. Read More

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Biomechanics of Ophthalmic Crosslinking.

Transl Vis Sci Technol 2021 Apr;10(5)

Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.

Crosslinking involves the formation of bonds between polymer chains, such as proteins. In biological tissues, these bonds tend to stiffen the tissue, making it more resistant to mechanical degradation and deformation. In ophthalmology, the crosslinking phenomenon is being increasingly harnessed and explored as a treatment strategy for treating corneal ectasias, keratitis, degenerative myopia, and glaucoma. Read More

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Self-guided Cognitive Behavioral Therapy Apps for Depression: Systematic Assessment of Features, Functionality, and Congruence With Evidence.

J Med Internet Res 2021 Jul 30;23(7):e27619. Epub 2021 Jul 30.

Centre for Population Health Sciences, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore, Singapore.

Background: Mental health disorders affect 1 in 10 people globally, of whom approximately 300 million are affected by depression. At least half of the people affected by depression remain untreated. Although cognitive behavioral therapy (CBT) is an effective treatment, access to mental health specialists, habitually challenging, has worsened because of the COVID-19 pandemic. Read More

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