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European Journal of Human Genetics :... Apr 2024News stories and patient-facing material about genetic tests are often illustrated by images, but the content of such images and the messages they propagate are rarely...
News stories and patient-facing material about genetic tests are often illustrated by images, but the content of such images and the messages they propagate are rarely scrutinised. Stock image banks were searched to identify a hundred images relating to genetic tests and analysed using a multimodal critical discourse approach, aiming to identify what the images featured, how they were composed, and what they communicated about genetic testing. We found that images tended to focus on technical aspects of sample processing (for example, pipetting) and drew on older technologies (for example slab gel electrophoresis) when representing data arising from genetic tests. Composition choices like focussing images around pipette tips, or emphasising colour or brightness of electrophoretic bands, represented genetic testing as precise, unambiguous and illuminating. Only 7% of images featured a person having a genetic test, and only one image alluded to communication of genetic results. Current popular visual representations of genetic testing rarely highlight the possibility of uncertain or non-diagnostic outcomes, and may contribute to high public expectations of informativeness and certainty from such tests.
Topics: Humans; Genetic Testing; Gels
PubMed: 38066171
DOI: 10.1038/s41431-023-01508-4 -
Diagnostic Microbiology and Infectious... May 2024The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic led to global shortages in laboratory consumables, in particular for automated PCR. The...
The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic led to global shortages in laboratory consumables, in particular for automated PCR. The Technical University of Denmark supported Danish hospitals from 2020 to 2022, conducting SARS-CoV-2 RT-qPCR on around 10,000 patient samples daily. We encountered shortages of disposable pipette tips used with automated liquid handlers that transferred oropharyngeal swab samples to 96-well microplates before RNA extraction. To enable tip reuse, we developed an automated protocol for washing tips with a 0.5 % sodium hypochlorite solution. This effectively eliminated carry-over of genomic material and the wash solution remained effective when stored in an open reservoir at ambient temperatures for 24 h. A three-day validation setup demonstrated the robustness of the tip wash protocol. Reducing the number of tips used for transferring samples to 96-well microplates from 96 to 8 enabled us to mitigate pipette tip shortages, lower costs, and minimize plastic waste generation.
Topics: Humans; SARS-CoV-2; COVID-19; COVID-19 Testing; Laboratories; RNA, Viral
PubMed: 38452555
DOI: 10.1016/j.diagmicrobio.2024.116241 -
The Science of the Total Environment Jul 2023A rapid virus concentration method is needed to get high throughput. Reliable results of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) detection in...
A rapid virus concentration method is needed to get high throughput. Reliable results of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) detection in wastewater are necessary for applications in wastewater-based epidemiology. In this study, an automated filtration method using a concentrating pipette (CP Select; Innovaprep) was applied to detect SARS-CoV-2 in wastewater samples with several modifications to increase its sensitivity and throughput. The performance of the CP Select method was compared to other concentration methods (polyethylene glycol precipitation and direct capture using silica column) to evaluate its applicability to SARS-CoV-2 detection in wastewater. SARS-CoV-2 RNA was successfully detected in six of eight wastewater samples using the CP Select method, whereas other methods could detect SARS-CoV-2 RNA in all wastewater samples. Enteric viruses, such as noroviruses of genogroups I (NoVs-GI) and II (NoVs-GII) and enteroviruses, were tested, resulting in 100 % NoVs-GII detection using all concentration methods. As for NoVs-GI and enteroviruses, all methods gave comparable number of detected samples in wastewater samples. This study showed that the optimized CP Select method was less sensitive in SARS-CoV-2 detection in wastewater than other methods, whereas all methods were applicable to detect or recover other viruses in wastewater.
Topics: Humans; SARS-CoV-2; Wastewater; COVID-19; RNA, Viral; Viruses; Norovirus; Enterovirus
PubMed: 37068668
DOI: 10.1016/j.scitotenv.2023.163487 -
BMC Pediatrics Feb 2024Neonatal jaundice is a condition caused by elevated levels of bilirubin in the bloodstream. Laboratory determination of serum bilirubin concentration by total serum... (Observational Study)
Observational Study
BACKGROUND
Neonatal jaundice is a condition caused by elevated levels of bilirubin in the bloodstream. Laboratory determination of serum bilirubin concentration by total serum bilirubin (TSB) test is still considered as gold standard for clinical guidance and practice. In developed countries, diagnosis of neonatal jaundice is shifting towards point-of-care medical devices. BiliDx is a device developed to allow a fast, blood-based determination of bilirubin levels at the point of care. This study aimed to determine the accuracy of the BiliDx device relative to a standard laboratory total serum bilirubin to diagnose and monitor jaundice among neonates admitted at Muhimbili National Hospital (MNH).
MATERIAL AND METHODOLOGY
This was a prospective hospital-based observational study conducted at the Neonatal Ward - MNH, Dar-es-Salaam, Tanzania from November 2022 to January 2023. A total of 180 neonates admitted at the neonatal ward with jaundice and whose parents consented were enrolled in the study. Blood samples were collected; 2 ml of venous blood into the vacutainer bottle for standard laboratory measurement of total serum bilirubin (TSB) and 25µL blood collected into a transfer pipette tube and applied to BiliDx. STATA version 15.1 was used for data analysis.
RESULTS
Out of 180 neonates, 39.4% (71/180) had birth weight between 1500 - 2499.9 g, approximately 2/3rd (120/180) were preterm, 92/180 (51.1%) were males and 100/180 (55.6%) were undergoing phototherapy treatment the moment sample taken. The mean bilirubin concentration was 92 mmol/l for BiliDx and 118 mmol/l for standard laboratory TSB. The minimum and maximum values obtained with BiliDx were, 3.4 and 427.5 mmol/l respectively, compared with 10.7 and 382.1 mmol/l using standard laboratory TSB. A linear relationship and correlation coefficient of 0.8408 (p = 0.000) between BiliDx and standard laboratory TSB was found. The regression analysis showed the presence of constant error [coefficient of BiliDx/slope = 0.91, 95% CI (0.82-0.99), p = 0.000] and random error exclusively [coefficient of constant/y-intercept = 48.52, 95%CI (37.70-59.34), p = 0.000]. The Bland-Altman plot showed an acceptable mean difference of 39.1mmol/l, limits of agreement of -48.3mmol/l to 126.4mmol/l, and 179 points (179/180 = 99.4%) lying inside the limits of agreement.
CONCLUSION
The results support the use of BiliDx for rapid and accurate testing of elevated levels of bilirubin in the bloodstream among neonates since 99.4% of the differences between BiliDx and standard laboratory TSB lie between the lines of agreement.
Topics: Infant, Newborn; Male; Humans; Female; Jaundice, Neonatal; Bilirubin; Point-of-Care Systems; Prospective Studies; Jaundice; Phototherapy; Hospitals; Neonatal Screening
PubMed: 38350890
DOI: 10.1186/s12887-024-04565-w -
Biophysical Journal Mar 2024Compaction is the first morphogenetic movement of the eutherian mammals and involves a developmentally regulated adhesion process. Previous studies investigated cellular...
Compaction is the first morphogenetic movement of the eutherian mammals and involves a developmentally regulated adhesion process. Previous studies investigated cellular and mechanical aspects of compaction. During mouse and human compaction, cells spread onto each other as a result of a contractility-mediated increase in surface tension pulling at the edges of their cell-cell contacts. However, how compaction may affect the mechanical stability of cell-cell contacts remains unknown. Here, we used a dual pipette aspiration assay on cell doublets to quantitatively analyze the mechanical stability of compacting mouse embryos. We measured increased mechanical stability of contacts with rupture forces growing from 40 to 70 nN, which was highly correlated with cell-cell contact expansion. Analyzing the dynamic molecular reorganization of cell-cell contacts, we find minimal recruitment of the cell-cell adhesion molecule Cdh1 (also known as E-cadherin) to contacts but we observe its reorganization into a peripheral adhesive ring. However, this reorganization is not associated with increased effective bond density, contrary to previous reports in other adhesive systems. Using genetics, we reduce the levels of Cdh1 or replace it with a chimeric adhesion molecule composed of the extracellular domain of Cdh1 and the intracellular domain of Cdh2 (also known as N-cadherin). We find that reducing the levels of Cdh1 impairs the mechanical stability of cell-cell contacts due to reduced contact growth, which nevertheless show higher effective bond density than wild-type contacts of similar size. On the other hand, chimeric adhesion molecules cannot form large or strong contacts indicating that the intracellular domain of Cdh2 is unable to reorganize contacts and/or is mechanically weaker than the one of Cdh1 in mouse embryos. Together, we find that mouse embryo compaction mechanically strengthens cell-cell adhesion via the expansion of Cdh1 adhesive rings that maintain pre-compaction levels of effective bond density.
PubMed: 38528761
DOI: 10.1016/j.bpj.2024.03.028 -
BMC Chemistry Apr 20246-mercaptopurine (6-MP) is a chemotherapy drug mainly used to treat leukemia. It is a persistent organic pollutant and can remain in the environment for a long period of...
BACKGROUND
6-mercaptopurine (6-MP) is a chemotherapy drug mainly used to treat leukemia. It is a persistent organic pollutant and can remain in the environment for a long period of time. The presence of 6-MP in the environment poses a number of hazards and needs to be assessed to monitor its potential risk to human health and the environment. However, due to its trace amount in complicated matrices, a clean-up and preconcentration step before its determination is compulsory.
RESULTS
As a highly efficient adsorbent for the extrication of 6-mercaptopurine (6-MP), a novel carbon nanotube doped with camphor: decanoic acid deep eutectic solvent was synthesized and applied as a packing material for the pipette-tip micro solid phase extraction sorbent of 6-MP from tap, wastewater and seawater samples before its spectrophotometric determination. Characteristics and structure of this adsorbent was fully investigated. Factors affecting extraction, including type and volume of the eluent, ionic strength and pH of the sample solution, amount of adsorbent, and number of extraction and elution cycles were optimized using one-factor-at-a-time and response surface methodologies. The method was found to be linear in the range of 1 to 1000 µg/L with a limit of detection and quantification of 0.2 and 0.7 µg/L, respectively. Reproducibility as relative standard deviation was better than 4.6%.
CONCLUSION
Application of deep eutectic solvent modified carbon nanotube indicated suitable microextraction results and good potential for rapid extraction of trace amounts of 6-MP from different aqueous samples. The amount of sample required for the analysis was less than 10 mL and only 1.5 mg of the adsorbent was used. The total analysis time, including extraction was less than 15 min and the adsorbent could be used for at least 10 times, without significantly losing its adsorption ability. Compared to using unmodified usual carbon nanotubes, deep eutectic solvent doped carbon nanotubes showed 19.8% higher extraction ability.
PubMed: 38654336
DOI: 10.1186/s13065-024-01199-y -
Neuroscience Research May 2024The gramicidin-perforated patch-clamp technique is indispensable for recording neuronal activities without changing the intracellular Cl concentration. Conventionally,...
The gramicidin-perforated patch-clamp technique is indispensable for recording neuronal activities without changing the intracellular Cl concentration. Conventionally, gramicidin contained in the pipette fluid is delivered to the cell membrane by passive diffusion. Gramicidin deposited on the pipette orifice sometimes hampers giga-seal formation, and perforation progresses only slowly. These problems may be circumvented by delivering a high concentration of gramicidin from an intra-pipette capillary after a giga-seal is formed. We herein describe the detailed protocol of this improved method. This protocol would greatly facilitate the investigation of Cl gradient-dependent neuronal activities.
PubMed: 38740268
DOI: 10.1016/j.neures.2024.05.002 -
BioRxiv : the Preprint Server For... May 2024Sperm cryopreservation is important for individuals undergoing infertility treatment, and for those who wish to preserve fertility potential, prior to treatments like...
Sperm cryopreservation is important for individuals undergoing infertility treatment, and for those who wish to preserve fertility potential, prior to treatments like chemotherapy, radiation therapy, gender-affirming medical interventions, elective fertility delay, or individuals in high-risk professions such as the military. Current methods for sperm cryopreservation result in approximately 30-50% decrease in sperm motility. However, recent studies have shown that ultra-rapid freezing (vitrification) is a valuable approach for maintaining sperm quality after freeze-thawing processes in the clinical laboratory setting and requires submicroliter to microliter volumes. A major challenge for the adoption of vitrification in fertility laboratories is the ability to pipette small volumes of sample. Here, we present a method that leverages open-channel droplet microfluidics to autonomously generate sub-microliter to microliter volumes of purified human sperm samples. Using a novel, open-channel droplet generator, we found no change in sperm movement and kinematic data after exposure to device and reagents in our platform. We conclude that our platform is compatible with human sperm, an important foundation for future implementation of vitrification in fertility laboratories.
PubMed: 38798664
DOI: 10.1101/2024.05.09.593416 -
Advanced Science (Weinheim,... Jun 2024Digital PCR (dPCR) holds immense potential for precisely detecting nucleic acid markers essential for personalized medicine. However, its broader application is hindered...
Digital PCR (dPCR) holds immense potential for precisely detecting nucleic acid markers essential for personalized medicine. However, its broader application is hindered by high consumable costs, complex procedures, and restricted multiplexing capabilities. To address these challenges, an all-in-one dPCR system is introduced that eliminates the need for microfabricated chips, offering fully automated operations and enhanced multiplexing capabilities. Using this innovative oscillation-induced droplet generation technique, OsciDrop, this system supports a comprehensive dPCR workflow, including precise liquid handling, pipette-based droplet printing, in situ thermocycling, multicolor fluorescence imaging, and machine learning-driven analysis. The system's reliability is demonstrated by quantifying reference materials and evaluating HER2 copy number variation in breast cancer. Its multiplexing capability is showcased with a quadruplex dPCR assay that detects key EGFR mutations, including 19Del, L858R, and T790M in lung cancer. Moreover, the digital stepwise melting analysis (dSMA) technique is introduced, enabling high-multiplex profiling of seven major EGFR variants spanning 35 subtypes. This innovative dPCR system presents a cost-effective and versatile alternative, overcoming existing limitations and paving the way for transformative advances in precision diagnostics.
Topics: Humans; Breast Neoplasms; Molecular Diagnostic Techniques; Reproducibility of Results; Polymerase Chain Reaction; Pathology, Molecular; ErbB Receptors; DNA Copy Number Variations; Lung Neoplasms; Receptor, ErbB-2; Multiplex Polymerase Chain Reaction; Mutation; Female
PubMed: 38516754
DOI: 10.1002/advs.202309557 -
Se Pu = Chinese Journal of... Mar 2024Algal toxins are secondary metabolites produced by harmful algae; these metabolites are characterized with strong toxicity, diverse structure and bioaccumulation....
Algal toxins are secondary metabolites produced by harmful algae; these metabolites are characterized with strong toxicity, diverse structure and bioaccumulation. Aquatic organisms that feed on harmful algae can accumulate algal toxins in their bodies, and the consumption of these organisms by humans can cause symptoms of paralysis, diarrhea, and even death. The onset of poisoning can occur within as little as 30 min; in many cases, no suitable antidote for algal toxins is available. Thus, algal toxins present significant threats to human health, the aquaculture industry, and aquatic ecosystems. Because the potential risks of algal toxins are a critical issue, these toxins have become a research hotspot. The water environment and various types of aquatic products should be monitored and analyzed to ensure their safety. However, because of possible matrix effects and the low content of algal toxins in actual samples, an efficient pretreatment method is necessary prior to instrumental analyses. Efficient sample pretreatment techniques can not only reduce or eliminate interferences from the sample matrix during analysis but also enrich the target analytes to meet the detection limit of the analytical instrument, thereby ensuring the sensitivity and accuracy of the detection method. In recent years, sample pretreatment techniques such as solid-phase extraction (SPE), solid-phase microextraction (SPME), magnetic SPE (MSPE), dispersive SPE (DSPE), and pipette tip-based SPE (PT-SPE) have gained wide attention in the field of algal-toxin separation and analysis. The performance of these pretreatment techniques largely depends on the characteristics of the extraction materials. Given the diverse physicochemical properties of algal toxins, including their different molecular sizes, hydrophobicity/hydrophilicity, and charges, the design and preparation of materials suitable for algal-toxin extraction is an essential undertaking. The optimal extraction material should be capable of reversible algal-toxin adsorption and preferably possess a porous structure with a large surface area to allow for high recovery rates and good interfacial contact with the toxins. Additionally, the extraction material should exhibit good chemical stability in the sample solution and elution solvent within the working pH range; otherwise, it may dissolve or lose its functional groups. Many research efforts have sought to develop novel adsorbent materials with these properties in the separation and analysis of algal toxins, focusing on carbon-based materials, metal organic frameworks (MOFs), covalent organic frameworks (COFs), molecularly imprinted polymers (MIPs), and their functionalized counterparts. Carbon-based materials, MOFs, and COFs have advantages such as large surface areas and abundant adsorption sites. These extraction materials are widely used in the separation and analysis of target substances in complex environmental, biological, and food samples owing to their excellent performance and unique microstructure. They are also the main adsorbents used for the extraction of algal toxins. These extraction materials play an essential role in the extraction of algal toxins, but they also present a number of limitations: (1) Carbon-based materials, MOFs, and COFs have relatively poor selective-adsorption ability towards target substances; (2) Most MOFs are unstable in aqueous solutions and challenging to apply during extraction from water-based sample solutions; (3) COFs mainly consist of lightweight elements, rendering them difficult to completely separate from sample solutions using centrifugal force, which limits their application range; (4) Although MIPs have good selectivity, issues such as template-molecule loss, slow mass-transfer rates, and low adsorption capacity must be addressed. Therefore, the design and preparation of novel functionalized extraction materials specifically tailored for algal toxins and studies on new composite extraction materials are highly desirable. This article collects representative literature from domestic and international research on algal-toxin analysis over the past decade, summarizes the relevant findings, categorizes the applications of novel functional materials in algal-toxin-extraction processes, and provides an outlook on their future development prospects.
Topics: Humans; Ecosystem; Adsorption; Aquaculture; Carbon; Water; Solid Phase Extraction
PubMed: 38503699
DOI: 10.3724/SP.J.1123.2023.10006