Publications by authors named "Hellwich M"

Objectives: To assess the performances of three commonly used antigen rapid diagnostic tests used as self-tests in asymptomatic individuals in the Omicron period.

Methods: We performed a cross-sectional diagnostic test accuracy study in the Omicron period in three public health service COVID-19 test sites in the Netherlands, including 3600 asymptomatic individuals aged ≥ 16 years presenting for SARS-CoV-2 testing for any reason except confirmatory testing after a positive self-test. Participants were sampled for RT-PCR (reference test) and received one self-test (either Acon Flowflex [Flowflex], MP Biomedicals (MPBio), or Siemens-Healthineers CLINITEST [CLINITEST]) to perform unsupervised at home.

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Background: The diagnostic accuracy of unsupervised self-testing with rapid antigen diagnostic tests (Ag-RDTs) is mostly unknown. We studied the diagnostic accuracy of a self-performed SARS-CoV-2 saliva and nasal Ag-RDT in the general population.

Methods: This large cross-sectional study consecutively included unselected individuals aged ≥ 16 years presenting for SARS-CoV-2 testing at three public health service test sites.

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Objective: To assess the performance of rapid antigen tests with unsupervised nasal and combined oropharyngeal and nasal self-sampling during the omicron period.

Design: Prospective cross sectional diagnostic test accuracy study.

Setting: Three public health service covid-19 test sites in the Netherlands, 21 December 2021 to 10 February 2022.

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Objectives: To evaluate the performance of nasal mid-turbinate self-testing using rapid antigen detection tests (RDT) for persons with suspected coronavirus disease 2019 (COVID-19) in the community. Self-testing for COVID-19 infection with lateral flow assay severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RDT, provides rapid results and could enable frequent and extensive testing in the community, thereby improving the control of SARS-CoV-2.

Methods: Participants visiting a municipal SARS-CoV-2 testing centre, received self-testing kits containing either the BD Veritor System (BD-RDT) or Roche SARS-CoV-2 antigen detection test (Roche-RDT).

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Occlusion of the middle cerebral artery (MCAo) is among the most common causes of ischemic stroke in humans. Cerebral ischemia leads to brain lesions existing of an irreversibly injured core and an ischemic boundary zone, the penumbra, containing damaged but potentially salvageable tissue. Using a transient occlusion (30 min) of the middle cerebral artery (tMCAo) mouse model in this cross-institutional study we investigated the neurorestorative efficacy of a dietary approach (Fortasyn) comprising docosahexaenoic acid, eicosapentaenoic acid, uridine, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium as therapeutic approach to counteract neuroinflammation and impairments of cerebral (structural+functional) connectivity, cerebral blood flow (CBF), and motor function.

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A total of 24 patients showing predominantly urticarial and/or anaphylactic reactions to analgesics were exposed to the suspicious agents by means of skin testing and oral provocation. Only two patients, who had already shown mild anaphylactic symptoms during the skin test, were excluded from the oral provocation test. In 19 out of 24 cases, the presumed intolerance of analgesics could be confirmed by oral provocations, i.

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Itchy pink plaques have been developing on the trunk of a 29-year-old patient for two years. After a few weeks, these plaques usually change into atropic scars. Both types of efflorescence occur simultaneously.

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In case of uncharacteristic patient complaints or slightly pathologic BSR or liver enzyme levels in patients, suffering from melanoma, the determination of 5-S-cysteinyldopa in the 24-h-urine may be of great diagnostic value. If the complaints and the pathologic values are early symptoms and signs of generalized metastases being clinically not yet manifest, the excretion of 5-S-cysteinyldopa in the urine is often increased. In such cases, a thorough and possibly invasive search for metastases is indicated.

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In reticulocyte-rich suspensions of red blood cells from rats extrusion of cAMP as a regulatory mechanism of intracellular cAMP was investigated. In response to isoprenaline and/or the phosphodiesterase inhibitors Ro 20-1724 and rolipram extrusion of cAMP increases dependent on the concentration of the drugs and time of exposure. However, these drugs exert their effects on the extrusion of cAMP only indirectly, i.

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When increasing reticulocytosis (up to 80%) was induced in rats by treatment with acetyl-phenylhydrazine (up to 70 mg/kg on 3 consecutive days) synthesis of cAMP stimulated by isoprenaline in intact red blood cells and in the related membrane preparations increased up to 100-fold. At the same time the density of beta-adrenoreceptor sites (measured by ligand binding with (3H)(-)-dihydroalprenolol) in the related membrane preparations was only increased about 5-fold. There was however a linear correlation between the increase of isoprenaline-stimulated enzyme activity and the receptor density in membrane preparations.

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