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Abstract Background The prevalence and death rate arising from malaria infection, and emergence of other diseases showing similar symptoms to malaria require the development of malaria-specific and sensitive devices for its diagnosis. To address this, the design and fabrication of low-cost, rapid, paper-based analytical devices (µPAD) using surface-immobilized aptamers to detect the presence of a recombinant malarial biomarker—Plasmodium falciparum lactate dehydrogenase (rPfLDH)—is reported in this study. Methods Test zones on paper surfaces were created by covalently immobilizing streptavidin to the paper, subsequently attaching biotinylated aptamers to streptavidin. Aptamers selectively bound rPfLDH. The measurement of captured rPfLDH enzyme activity served as the means of detecting this biomarker. Enzyme activity across three replicate sensors was digitally quantified using the colorimetric Malstat assay. Results Screening of several different aptamers reported in the literature showed that aptamers rLDH7 and 2008s immobilized in this manner specifically recognised and captured PfLDH. Using rLDH7, the sensitivity of the µPAD sensor was evaluated and the µPAD sensor was applied for preferential detection of rPfLDH, both in buffered solutions of the protein and in spiked serum and red blood cell lysate samples. In buffered solutions, the test zone of the µPAD sensor exhibited a K D of 24 ± 11 nM and an empirical limit of detection of 17 nM, respectively, a limit similar to commercial antibody-based sensors exposed to rPfLDH. The specific recognition of 133 nM rPfLDH in undiluted serum and blood samples was demonstrated by the µPAD. Conclusion The reported µPAD demonstrates the potential of integrating aptamers into paper-based malarial rapid diagnostic tests. Graphical Abstract The assembly of µPAD sensors using APTEC assay principles for the detection the malarial biomarker, lactate dehydrogenase enzymes from Plasmodium falciparum (PfLDH). The aptamers immobilized at the test zones capture the PfLDH in samples. After washing the unbound sample components from the zones, Malstat assay reagents are added for colour development, proportional to the amount of captured PfLDH.

Paper-based sensors have received increasing attention in the last decade, their use has spread to various application fields, such as clinical diagnostic, food safety, environmental monitoring, etc. Feature inherent to on-side detection is suitable to be used as point-of-care (POC) testing, including avoided sampling, sample preparation, and laborious procedure in the classical clinical lab, which is undoubtedly driving many developments of this lab-on-paper technology. The detection of biomarkers that are related to human health conditions has to play important role in the indication of the risk of diseases. In this review, the development of paper-based sensors for the detection of important biomarkers is presented. The also emphasis on recognition elements, such as chromophores/fluorophores, plasmonic nanoparticles, metal nanoclusters, etc., used to serve suitable selectivity and sensitivity. The performance of paper-based sensors using various techniques, including optical and electrochemical and other detection techniques are addressed. Furthermore, their limitations and prospects are discussed. The review also highlights cutting-edge technologies for further enhancement in the sensor performances for biomarkers detection.

Total bilirubin values have been used as a potential marker to pre-screen and diagnose various liver-based diseases such as jaundice, bile obstruction, liver cancer, etc. A device known as KromaHealth Kit, composed of paper and an acrylic backbone, is developed to quantify total bilirubin in human serum using image processing and machine learning technology. The biochemical assays are deposited on absorbent paper pads that act as reaction zones when serum is added. A dedicated smartphone app captures images of the colorimetric changes on the pad and converts them into quantitative values of bilirubin. The range of bilirubin concentration that can be quantified using the device ranges from 0.5 mg/dl to 7.0 mg/dl. The precision, limit of detection, interference analysis, linearity, stability, and comparison with a predicate are studied in this paper in accordance with clinical and laboratory standards institute. The results indicate that the KromaHealth Kit can be used as an inexpensive alternative to conventional bilirubin testing in clinical settings. With its level of precision, ease-of-use, long shelf-life, and short turnaround time, it will prove to be invaluable in limited-resource settings.

This ENETS guidance paper for well‐differentiated nonfunctioning pancreatic neuroendocrine tumours (NF‐Pan‐NET) has been developed by a multidisciplinary working group, and provides up‐to‐date and practical advice on the management of these tumours. Using the extensive experience of centres treating patients with NF‐Pan‐NEN, the authors of this guidance paper discuss 10 troublesome questions in everyday clinical practice. Our many years of experience in this field are still being verified in the light of the results of new clinical, which set new ways of proceeding in NEN. The treatment of NF‐Pan‐NEN still requires a decision of a multidisciplinary team of specialists in the field of neuroendocrine neoplasms. This ENETS guidance paper provides up‐to‐date practical advice on the NF‐Pan‐NET diagnosis and treatment. Management of NF‐Pan‐NET patients requires a NET‐dedicated MDT decision. ENETS Centres of Excellence should be strongly considered to be involved in the diagnostic‐therapeutic strategy of these patients. Further studies are needed to fulfil the unmet needs in this field focusing on prognostic molecular markers, dilemmas concerning the selection of a therapeutic approach as well as the sequence of their use to achieve success in the management of NF‐Pan‐NETs patients. [ABSTRACT FROM AUTHOR]

Within the last decade, challenges of diagnosis have emerged on the global health agenda, accompanied by an expansion in the use of point-of-care and rapid detection devices in low-resource contexts where laboratory facilities are scarce. Few studies have explored how these changes are shaping people’s diagnostic journeys and their modes of accessing such technologies. In this paper I show how sick people and their families in a peri-urban area in Burkina Faso attempt to access diagnostic technologies and make themselves visible to the healthcare system through papers. In this context, I show how referral papers and diagnostic papers take on significance for people as they attempt to access care and diagnostic technologies and ‘carry’ knowledge between different levels of the healthcare system. The use of papers is often an uncertain undertaking, as they remain unintelligible to the sick and the layperson. I highlight how the form of the papers makes a crucial difference to the ways that sick people are able to use them. Papers and diagnostic technologies present both opportunities and challenges, and simultaneously engender hope, uncertainty, disappointment, and despair for the sick seeking a cure. Uncertainties, especially financial ones, arise with the possibility of new referrals and diagnostic tests, and along the way many give up or are immobilised when faced with diagnostic ambiguity.

Benign conditions of the lower urinary tract, including benign prostatic hyperplasia, overactive bladder syndrome, and stress urinary incontinence, are frequent in the general population. Despite their benign nature, they have major adverse effects on the quality of life of the afflicted patients and their partners. Despite major progress in the diagnosis and treatment of these conditions, improved understanding and management of these patients remain substantial medical needs. This editorial discusses some recent high-quality articles published in the Journal of Clinical Medicine on the understanding of the epidemiology, pathophysiology, diagnostic, and treatment of benign diseases of the lower urinary tract tissues such as the bladder and prostate.

Abstract Background Propensity scores are widely used to deal with confounding bias in medical research. An incorrectly specified propensity score model may lead to residual confounding bias; therefore it is essential to use diagnostics to assess propensity scores in a propensity score analysis. The current use of propensity score diagnostics in the medical literature is unknown. The objectives of this study are to (1) assess the use of propensity score diagnostics in medical studies published in high-ranking journals, and (2) assess whether the use of propensity score diagnostics differs between studies (a) in different research areas and (b) using different propensity score methods. Methods A PubMed search identified studies published in high-impact journals between Jan 1st 2014 and Dec 31st 2016 using propensity scores to answer an applied medical question. From each study we extracted information regarding how propensity scores were assessed and which propensity score method was used. Research area was defined using the journal categories from the Journal Citations Report. Results A total of 894 papers were included in the review. Of these, 187 (20.9%) failed to report whether the propensity score had been assessed. Commonly reported diagnostics were p-values from hypothesis tests (36.6%) and the standardised mean difference (34.6%). Statistical tests provided marginally stronger evidence for a difference in diagnostic use between studies in different research areas (p = 0.033) than studies using different propensity score methods (p = 0.061). Conclusions The use of diagnostics in the propensity score medical literature is far from optimal, with different diagnostics preferred in different areas of medicine. The propensity score literature may improve with focused efforts to change practice in areas where suboptimal practice is most common.

Male lower urinary tract dysfunction represents a common problem in the community. Physicians should approach these patients based on the best available evidence. This summary provides the up-to-date recommendations for the evaluation and the management of men with lower urinary tract symptoms. Lower urinary tract symptoms (LUTS) are common, often bothersome, and have multifactorial aetiology. To present a summary of the 2023 version of the European Association of Urology guidelines on the management of male LUTS. A structured literature search from 1966 to 2021 selected the articles with the highest certainty evidence. The Delphi technique consensus approach was used to develop the recommendations. The assessment of men with LUTS should be practical. A careful medical history and physical examination are essential. Validated symptom scores, urine test, uroflowmetry, and postvoid urine residual, as well as frequency-volume charts for patients with nocturia or predominately storage symptoms should be used. Prostate-specific antigen should be ordered if a diagnosis of prostate cancer changes the treatment plan. Urodynamics should be performed for selected patients. Men with mild symptoms are candidates for watchful waiting. Behavioural modification should be offered to men with LUTS prior to, or concurrent with, treatment. The choice of medical treatment depends on the assessment findings, predominant type of symptoms, ability of the treatment to change the findings, and the expectations to be met in terms of the speed of onset, efficacy, side effects, and disease progression. Surgery is reserved for men with absolute indications, and for patients who fail or prefer not to receive medical therapy. Surgical management has been divided into five sections: resection, enucleation, vaporisation, and alternative ablative and nonablative techniques. The choice of surgical technique depends on patient's characteristics, expectations, and preferences; surgeon's expertise; and availability of modalities. The guidelines provide an evidence-based approach for the management of male LUTS. A clinical assessment should identify the cause(s) of symptoms and define the clinical profile and patient's expectations. The treatment should aim to ameliorate symptoms and reduce the risk of complications. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the bibliometric data of the most common publication types of the neuroimaging literature.Methods: PubMed was searched to identify all published papers with “neuroimaging” as their MeSH Major Topics, and they were further searched by the following publication types: case report, clinical trial, comparative study, editorial, evaluation study, guideline, meta-analysis, multicenter study, randomized controlled trial, review, technical report, and validation study. The proportion of papers belonging to each publication type published in neuroimaging journals was calculated. Year-adjusted mean citation counts for each publication type were computed using data from Web of Science. Publication trend and its correlation with citation performance were assessed.Results: Review and comparative study were the most common publication types. Publication types with the highest proportion in neuroimaging journals were guideline, validation study, and technical reports. Since the year 2000, multicenter study, review, and meta-analysis showed the strongest linear increase in annual publication count. These publication types also had the highest year-adjusted citation counts (4.7–10.0). Publication types with the lowest year-adjusted citation counts were editorial and case report (0.5–1.0). It was estimated that 12.5% of the publications labeled as case reports were incorrectly labeled.Conclusions: Neuroimaging literature has been expanding with papers of higher levels of evidence, such as meta-analyses, multicenter studies, and randomized controlled trials.

The following article summarizes United States Patent Application No. US20180052155A1, titled ‘Assay Devices and Methods’ (filed 16 August 2016, published 22 February 2018). While lateral flow assays (LFAs) have revolutionized point-of-care diagnostics by enabling accurate, inexpensive, and rapid detection of biomarkers, they typically do not provide quantitative results. Hence, there is a significant need for quantitative assays at the point of care. This patent summary describes a novel method of chronometric biomarker quantitation via enzymatic degradation of a metastable gelatin-based biomatrix, principally suited for use in paper-based microfluidic devices (microPADs). This new quantitation mechanism was designed to meet the ASSURED criteria for point-of-care diagnostic devices laid forth by the World Health Organization and may ultimately provide increased access to healthcare, at a significantly reduced cost, around the world.

Listeria monocytogenes is the third most deadly foodborne pathogen in the United States. The bacterium is found in soil and water, contaminating raw food products and the processing environment, where it can persist for an extended period. Currently, testing of food contact and non-food contact surfaces is performed using an array of sampling devices and endpoint technologies, offering various levels of sensitivity, cost, user skill, and time to detection. Paper-based microfluidic devices (µPADs) are a rapid detection platform amenable to low-cost, user-friendly, and portable diagnostics. In this study, we developed and evaluated a µPAD platform specific for the colorimetric detection of the Listeria genus following recovery from food contact and non-food contact surfaces. For detection, four colorimetric substrates specific for the detection of β-glucosidase, two broths selective for the detection of Listeria spp., and a nonselective broth were evaluated to facilitate detection of Listeria spp. The limit of detection and time to detection were determined by using pure bacterial cultures. After 8 h enrichment, L. monocytogenes (102 Colony Forming Units (CFU)/coupon) was detected on every surface. After 18 h enrichment, L. monocytogenes (102 CFU/coupon) was detected on all surfaces with all swabbing devices. This study demonstrated the ability of the µPAD-based method to detect potentially stressed cells at low levels of environmental contamination.

Benign conditions of the lower urinary tract, including benign prostatic hyperplasia, overactive bladder syndrome, and stress urinary incontinence, are frequent in the general population. Despite their benign nature, they have major adverse effects on the quality of life of the afflicted patients and their partners. Despite major progress in the diagnosis and treatment of these conditions, improved understanding and management of these patients remain substantial medical needs. This editorial discusses some recent high-quality articles published in the Journal of Clinical Medicine on the understanding of the epidemiology, pathophysiology, diagnostic, and treatment of benign diseases of the lower urinary tract tissues such as the bladder and prostate. [ABSTRACT FROM AUTHOR]

Paper-based sensors are a new alternative technology for fabricating simple, low-cost, portable and disposable analytical devices for many application areas including clinical diagnosis, food quality control and environmental monitoring. The unique properties of paper which allow passive liquid transport and compatibility with chemicals/biochemicals are the main advantages of using paper as a sensing platform. Depending on the main goal to be achieved in paper-based sensors, the fabrication methods and the analysis techniques can be tuned to fulfill the needs of the end-user. Current paper-based sensors are focused on microfluidic delivery of solution to the detection site whereas more advanced designs involve complex 3-D geometries based on the same microfluidic principles. Although paper-based sensors are very promising, they still suffer from certain limitations such as accuracy and sensitivity. However, it is anticipated that in the future, with advances in fabrication and analytical techniques, that there will be more new and innovative developments in paper-based sensors. These sensors could better meet the current objectives of a viable low-cost and portable device in addition to offering high sensitivity and selectivity, and multiple analyte discrimination. This paper is a review of recent advances in paper-based sensors and covers the following topics: existing fabrication techniques, analytical methods and application areas. Finally, the present challenges and future outlooks are discussed.

Reagent pencils allow for solvent-free deposition of reagents onto paper-based microfluidic devices. The pencils are portable, easy to use, extend the shelf-life of reagents, and offer a platform for customizing diagnostic devices at the point of care. In this work, reagent pencils were characterized by measuring the wear resistance of pencil cores made from polyethylene glycols (PEGs) with different molecular weights and incorporating various concentrations of three different reagents using a standard pin abrasion test, as well as by measuring the efficiency of reagent delivery from the pencils to the test zones of paper-based microfluidic devices using absorption spectroscopy and digital image colorimetry. The molecular weight of the PEG, concentration of the reagent, and the molecular weight of the reagent were all found to have an inverse correlation with the wear of the pencil cores, but the amount of reagent delivered to the test zone of a device correlated most strongly with the concentration of the reagent in the pencil core. Up to 49% of the total reagent deposited on a device with a pencil was released into the test zone, compared to 58% for reagents deposited from a solution. The results suggest that reagent pencils can be prepared for a variety of reagents using PEGs with molecular weights in the range of 2000 to 6000 g/mol.

This paper presents a lateral flow assay (LFA) for the quantitative, fluorescence-based detection of the cardiac biomarker troponin I (cTnI) that features an analytical strip made of cellulose filter paper. The results show that the wicking and test time are comparable to those obtained with conventional nitrocellulose (NC)-based LFAs. Further, the cellulose paper provides an excellent background with no auto-fluorescence that is very adequate in detecting fluorescent lines. While fluorescence that was generated with cellulose strips was lower when compared to that generated in NC strips, signals could be improved by layering carbon nanofibers (CNF) on the cellulose. A nonlinear behavior of the concentration–response relationship was observed for the LFA architectures with NC, cellulose, and cellulose-CNF in the 0 to 200 ng/mL cTnI concentration range. The measurements were consistent and characterized by coefficients of variation lower than 2.5%. Detection and quantitation limits that were in the range 1.28–1.40 ng/mL and 2.10–2.75 ng/mL were obtained for LFA with cellulose and cellulose CNF strips that are equivalent to the limits obtained with the standard NC LFA. Overall, we showed that commercially available filter paper can be used in the analytical strip of LFA.

Objective: Computerized neglect tests could significantly deepen our disorder-specific knowledge by effortlessly providing additional behavioral markers that are hardly or not extractable from existing paper-and-pencil versions. This study investigated how testing format (paper versus digital), and screen size (small, medium, large) affect the Center of cancelation (CoC) in right-hemispheric stroke patients in the Letters and the Bells cancelation task. Our second objective was to determine whether a machine learning approach could reliably classify patients with and without neglect based on their search speed, search distance, and search strategy. Method: We compared the CoC measure of right hemisphere stroke patients with neglect in two cancelation tasks across different formats and display sizes. In addition, we evaluated whether three additional parameters of search behavior that became available through digitization are neglect-specific behavioral markers. Results: Patients' CoC was not affected by test format or screen size. Additional search parameters demonstrated lower search speed, increased search distance, and a more strategic search for neglect patients than for control patients without neglect. Conclusion: The CoC seems robust to both test digitization and display size adaptations. Machine learning classification based on the additional variables derived from computerized tests succeeded in distinguishing stroke patients with spatial neglect from those without. The investigated additional variables have the potential to aid in neglect diagnosis, in particular when the CoC cannot be validly assessed (e.g., when the test is not performed to completion). [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and user-friendly diagnostics to detect the hypervirulent K. pneumoniae. • CRISPR-assisted point-of-need tool that stands worthy of the ASSURED criteria. • Species-specific detection of solely the test-strains of K. pneumoniae. • No cross-reactivity observed when tested on different genera besides the test strains. • Instrument-free readout to extend the reach of the technology to remote locations. Klebsiella pneumoniae , a prevalent healthcare-associated pathogen, poses a significant challenge to diagnosis and treatment due to its virulence and antimicrobial resistance. The demand for more efficient, precise and accessible diagnostic methods is imperative, as current approaches are labor-intensive and resource-dependent. In this study, a CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-based diagnostic tool for rapid detection of hypervirulent K. pneumoniae infections was proposed. We integrated recombinase polymerase amplification (RPA) coupled with a lateral flow assay and Cas13a (CRISPR associated protein 13a) to target the housekeeping rpoB gene for species-specific detection and the capsular polysaccharide regulating gene rmpA for identification of hypervirulent strains of K. pneumoniae. Tested on 18 K. pneumoniae strains, the devised tool successfully detected hypervirulent strains K. pneumoniae M59 and K. pneumoniae KP109 showing presence of rmpA. This study allows to develop an instrument-free platform for routine diagnosis of K. pneumoniae from serum, urine, and saliva samples that would empower healthcare personnel to facilitate proper and timely treatment of infections caused by the K. pneumoniae. [ABSTRACT FROM AUTHOR]