565 research outputs found

    Aptamer-Based Detection of Ampicillin in Urine Samples

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    The misuse of antibiotics in health care has led to increasing levels of drug resistant infections (DRI's) occurring in the general population. Most technologies developed for the detection of DRI's typically focus on phenotyping or genotyping bacterial resistance rather than on the underlying cause and spread of DRI's; namely the misuse of antibiotics. An aptameric based assay has been developed for the monitoring of ampicillin in urine samples, for use in determining optimal antibiotic dosage and monitoring patient compliance with treatment. The fluorescently labelled aptamers were shown to perform optimally at pH 7, ideal for buffered clinical urine samples, with limits of detection as low as 20.6 nM, allowing for determination of ampicillin in urine in the clinically relevant range of concentrations (100 nM to 100 µM). As the assay requires incubation for only 1 h with a small sample volume, 50 to 150 µL, the test would fit within current healthcare pathways, simplifying the adoption of the technology

    Heterogeneity in Blood Pressure Response to 4 Antihypertensive Drugs: A Randomized Clinical Trial

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    Importance: Hypertension is the leading risk factor for premature death worldwide. Multiple blood pressure-lowering therapies are available but the potential for maximizing benefit by personalized targeting of drug classes is unknown. Objective: To investigate and quantify the potential for targeting specific drugs to specific individuals to maximize blood pressure effects. Design, Setting, and Participants: A randomized, double-blind, repeated crossover trial in men and women with grade 1 hypertension at low risk for cardiovascular events at an outpatient research clinic in Sweden. Mixed-effects models were used to assess the extent to which individuals responded better to one treatment than another and to estimate the additional blood pressure lowering achievable by personalized treatment. Interventions: Each participant was scheduled for treatment in random order with 4 different classes of blood pressure-lowering drugs (lisinopril [angiotensin-converting enzyme inhibitor], candesartan [angiotensin-receptor blocker], hydrochlorothiazide [thiazide], and amlodipine [calcium channel blocker]), with repeated treatments for 2 classes. Main Outcomes and Measures: Ambulatory daytime systolic blood pressure, measured at the end of each treatment period. Results: There were 1468 completed treatment periods (median length, 56 days) recorded in 270 of the 280 randomized participants (54% men; mean age, 64 years). The blood pressure response to different treatments varied considerably between individuals (P <.001), specifically for the choices of lisinopril vs hydrochlorothiazide, lisinopril vs amlodipine, candesartan vs hydrochlorothiazide, and candesartan vs amlodipine. Large differences were excluded for the choices of lisinopril vs candesartan and hydrochlorothiazide vs amlodipine. On average, personalized treatment had the potential to provide an additional 4.4 mm Hg-lower systolic blood pressure. Conclusions and Relevance: These data reveal substantial heterogeneity in blood pressure response to drug therapy for hypertension, findings that may have implications for personalized therapy. Trial Registration: ClinicalTrials.gov Identifier: NCT02774460

    Clinical validation of automated and rapid mariPOC SARS-CoV-2 antigen test

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    Publisher Copyright: © 2021, The Author(s).COVID-19 diagnostics was quickly ramped up worldwide early 2020 based on the detection of viral RNA. However, based on the scientific knowledge for pre-existing coronaviruses, it was expected that the SARS-CoV-2 RNA will be detected from symptomatic and at significant rates also from asymptomatic individuals due to persistence of non-infectious RNA. To increase the efficacy of diagnostics, surveillance, screening and pandemic control, rapid methods, such as antigen tests, are needed for decentralized testing and to assess infectiousness. A novel automated mariPOC SARS-CoV-2 test was developed for the detection of conserved structural viral nucleocapsid proteins. The test utilizes sophisticated optical laser technology for two-photon excitation and individual detection of immunoassay solid-phase particles. We validated the new method against qRT-PCR. Sensitivity of the test was 100.0% (13/13) directly from nasopharyngeal swab specimens and 84.4% (38/45) from swab specimens in undefined transport mediums. Specificity of the test was 100.0% (201/201). The test's limit of detection was 2.7 TCID50/test. It showed no cross-reactions. Our study shows that the new test can detect infectious individuals already in 20 min with clinical sensitivity close to qRT-PCR. The mariPOC is a versatile platform for syndromic testing and for high capacity infection control screening of infectious individuals.Peer reviewe

    EGFR gene amplification is relatively common and associates with outcome in intestinal adenocarcinoma of the stomach, gastro-oesophageal junction and distal oesophagus

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    BACKGROUND Approximately 50 % of gastric adenocarcinomas belong to a molecular subgroup characterised by chromosomal instability and a strong association with the intestinal histological subtype. This subgroup typically contains alterations in the receptor tyrosine kinase-RAS pathway, for example EGFR or HER2 gene amplifications leading to protein overexpression. In clinical practice, HER2 overexpressing metastatic gastric cancer is known to respond to treatment with anti-HER2 antibodies. By contrast, anti-EGFR antibodies have not been able to provide survival benefit in clinical trials, which, however, have not included patient selection based on the histological subtype or EGFR gene copy number analysis of the tumours. To examine the role of EGFR as a potential biomarker, we studied the prevalence, clinicopathological associations as well as prognostic role of EGFR and HER2 expression and gene amplification in intestinal adenocarcinomas of the stomach, gastro-oesophageal junction and distal oesophagus. METHODS Tissue samples from 220 patients were analysed with EGFR and HER2 immunohistochemistry. Those samples with moderate/strong staining intensity were further analysed with silver in situ hybridization to quantify gene copy numbers. The results were associated with clinical patient characteristics and survival. RESULTS Moderate/strong EGFR protein expression was found in 72/220 (32.7 %) and EGFR gene amplification in 31/220 (14.1 %) of the tumours, while moderate/strong HER2 protein expression was detected in 31/220 (14.1 %) and HER2 gene amplification in 29/220 (13.2 %) of the tumours. EGFR and HER2 genes were co-amplified in eight tumours (3.6 %). EGFR gene amplification was more common in tumours of distal oesophagus/gastro-oesophageal junction/cardia than in those of gastric corpus (p = 0.013). It was associated with shortened time to cancer recurrence (p = 0.026) and cancer specific survival (p = 0.033). CONCLUSIONS EGFR gene amplification is relatively common in intestinal adenocarcinomas and associates with decreased survival. It is rarely concurrent with HER2 gene amplification, suggesting that anti-EGFR therapies might be applicable to some patients not eligible for anti-HER2 treatment. Analogous to HER2 testing, determination of EGFR gene amplification status in concert with immunohistochemistry could improve the specificity of patient selection when investigating the possible benefits of anti-EGFR therapies in the treatment of gastric adenocarcinomas

    Enhanced cosmic-ray flux toward zeta Persei inferred from laboratory study of H3+ - e- recombination rate

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    The H3+ molecular ion plays a fundamental role in interstellar chemistry, as it initiates a network of chemical reactions that produce many interstellar molecules. In dense clouds, the H3+ abundance is understood using a simple chemical model, from which observations of H3+ yield valuable estimates of cloud path length, density, and temperature. On the other hand, observations of diffuse clouds have suggested that H3+ is considerably more abundant than expected from the chemical models. However, diffuse cloud models have been hampered by the uncertain values of three key parameters: the rate of H3+ destruction by electrons, the electron fraction, and the cosmic-ray ionisation rate. Here we report a direct experimental measurement of the H3+ destruction rate under nearly interstellar conditions. We also report the observation of H3+ in a diffuse cloud (towards zeta Persei) where the electron fraction is already known. Taken together, these results allow us to derive the value of the third uncertain model parameter: we find that the cosmic-ray ionisation rate in this sightline is forty times faster than previously assumed. If such a high cosmic-ray flux is indeed ubiquitous in diffuse clouds, the discrepancy between chemical models and the previous observations of H3+ can be resolved.Comment: 6 pages, Nature, in pres

    What do European women know about their female cancer risks and cancer screening? A cross-sectional online intervention survey in five European countries

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    OBJECTIVES: Informed decisions about cancer screening require accurate knowledge regarding cancer risks and screening. This study investigates: (1) European women's knowledge of their risk of developing breast, ovarian, cervical or endometrial cancer, (2) their knowledge about mammography screening and (3) whether an evidence-based leaflet improves their knowledge. DESIGN: Cross-sectional online intervention survey. SETTING: National samples from five European countries (Czech Republic, Germany, UK, Italy and Sweden)-drawn from the Harris Interactive and the Toluna panel, respectively, in January 2017-were queried on their knowledge of age-specific risks of developing breast, cervical, ovarian or endometrial cancer within the next 10 years and of mammography screening before and after intervention. PARTICIPANTS: Of 3629 women (inclusion criteria: age 40-75 years) invited, 2092 responded and 1675 completed the survey (response rate: 61.4%). INTERVENTION: Evidence-based leaflet summarising information on age-adjusted female cancer risks, mammography and aspects of cancer prevention. PRIMARY OUTCOME MEASURES: Proportion of women (1) accurately estimating their risk of four female cancers, (2) holding correct assumptions of mammography screening and (3) changing their estimations and assumptions after exposure to leaflet. FINDINGS: Across countries, 59.2% (95% CI 56.8% to 61.6%) to 91.8% (95% CI 90.3% to 93.0%) overestimated their female cancer risks 7-33 fold (mediansacross tumours: 50.0 to 200.0). 26.5% (95% CI 24.4% to 28.7%) were aware that mammography screening has both benefits and harms. Women who accurately estimated their breast cancer risk were less likely to believe that mammography prevents cancer (p<0.001). After leaflet intervention, knowledge of cancer risks improved by 27.0 (95% CI 24.9 to 29.2) to 37.1 (95% CI 34.8 to 39.4) percentage points and of mammography by 23.0 (95% CI 21.0 to 25.1) percentage points. CONCLUSION: A considerable number of women in five European countries may not possess the prerequisites for an informed choice on cancer screening. Evidence-based information in patient leaflets can improve this situation

    Clinical validation of automated and rapid mariPOC SARS-CoV-2 antigen test

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    COVID-19 diagnostics was quickly ramped up worldwide early 2020 based on the detection of viral RNA. However, based on the scientific knowledge for pre-existing coronaviruses, it was expected that the SARS-CoV-2 RNA will be detected from symptomatic and at significant rates also from asymptomatic individuals due to persistence of non-infectious RNA. To increase the efficacy of diagnostics, surveillance, screening and pandemic control, rapid methods, such as antigen tests, are needed for decentralized testing and to assess infectiousness. A novel automated mariPOC SARS-CoV-2 test was developed for the detection of conserved structural viral nucleocapsid proteins. The test utilizes sophisticated optical laser technology for two-photon excitation and individual detection of immunoassay solid-phase particles. We validated the new method against qRT-PCR. Sensitivity of the test was 100.0% (13/13) directly from nasopharyngeal swab specimens and 84.4% (38/45) from swab specimens in undefined transport mediums. Specificity of the test was 100.0% (201/201). The test's limit of detection was 2.7 TCID50/test. It showed no cross-reactions. Our study shows that the new test can detect infectious individuals already in 20 min with clinical sensitivity close to qRT-PCR. The mariPOC is a versatile platform for syndromic testing and for high capacity infection control screening of infectious individuals.</p
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