Low-energy-consumption rapid synthesis of carbon dots at room temperature from combusted food waste with versatile analytical applications

In this study, we developed a low-energy-consumption green method for synthesising carbon dots (CD) at room temperature using watermelon rind as the carbon source through a cutting process based on NaCl crystals. The synthesis process was rapid (<5 min) and facile. The synthesised CD were characterised using photoluminescence (PL) spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy. The results revealed that the synthesised dots exhibited robust adsorption, a spherical shape and a uniform size distribution. The PL intensity of the quantum dots decrease due to the temperature rising, metal ions and ponceau 4R added. In contrast with PH, PL intensity increase, so these CD can serve as multifunctional sensing materials. Overall, this study presents an environmentally friendly method for the rapid synthesis of CD that are suitable for temperature, pH, metal ion and food sensing applications.

A review of analytical parameters in 'rapid' liquid chromatographic methods for bioanalysis: Can we do better?

Rapid bioanalysis is beneficial to many applications. However, how 'rapid' a method is, or could be, is often an unanswered question. In this statistical review, the authors have assessed multiple pre-analytical (i.e. sample preparation), and analytical method parameters specifically for liquid chromatography to assist researchers in developing and validating 'rapid' bioanalytical methods. We restricted the search to urine and plasma matrices only. Data were extracted from over 2,000 recent studies and evaluated to assess how these parameters affected the 'on-instrument' analysis time. In addition to methods using ultra-violet (UV) detection, there were a large number of mass spectrometric (MS) methods, allowing additional review of the differences between high- and low-resolution MS on analysis time. We observed that most (N = 922, 70 %) methods used 5 or 10 cm columns, and that whilst uptake of ultra-high performance (U)HPLC columns was good, the use of sub-5 cm columns and/or flow rates in excess of 1 mL/min was incredibly rare (N = 25, 3 %). The detector of choice for quantitative (U)HPLC-MS remains the triple quadrupole, although a number of groups report the use of high-resolution MS for such methods.

Rapid exome sequencing for children with severe acute encephalopathy - A case series

Increasingly, next-generation sequencing (NGS) is becoming an invaluable tool in the diagnosis of unexplained acute neurological disorders, such as acute encephalopathy/encephalitis. Here, we describe a brief series of pediatric patients who presented at the pediatric intensive care unit with severe acute encephalopathy, initially suspected as infectious or inflammatory but subsequently diagnosed with a monogenic disorder. Rapid exome sequencing was performed during the initial hospitalization of three unrelated patients, and results were delivered within 7-21 days. All patients were previously healthy, 1.5-3 years old, of Muslim Arab descent, with consanguineous parents. One patient presenting with acute necrotizing encephalopathy (ANEC). Her sister presented with ANEC one year prior. Exome sequencing was diagnostic in all three patients. All were homozygous for pathogenic and likely-pathogenic variants associated with recessive disorders; MOCS2, NDUFS8 and DBR1. Surprisingly, the initial workup was not suggestive of the final diagnosis. This case series demonstrates that the use of rapid exome sequencing is shifting the paradigm of diagnostics even in critical care situations and should be considered early on in children with acute encephalopathy. A timely diagnosis can direct initial treatment as well as inform decisions regarding long-term care.

The Society for Pediatric Radiology Magnetic Resonance Imaging and Emergency and Trauma Imaging Committees' consensus protocol recommendation for rapid MRI for evaluating suspected appendicitis in children

The imaging evaluation of acute abdominal pain in children with suspected appendicitis has evolved to include rapid abdominopelvic MRI (rMRI) over recent years. Through a collaborative effort between the Magnetic Resonance Imaging (MRI) and Emergency and Trauma Imaging Committees of the Society for Pediatric Radiology (SPR), we conducted a survey on the utilization of rMRI to assess practice specifics and protocols. Subsequently, we present a proposed consensus rMRI protocol derived from the survey results, literature review, and discussion and consensus between committee members.

A rapid method for DNA Isolation from blood, dried blood spots and rapid diagnosis test

Background & objectives

Malaria is a parasitic disease spread by Plasmodium parasite. Microscopy, lateral flow devices such as the Rapid Diagnostic Test (RDT), molecular methods such as Polymerase Chain Reaction (PCR), isothermal methods such as Loop-mediated isothermal amplification (LAMP), and other diagnostic methods are available for malaria. On the other hand, the accuracy of molecular diagnosis is dependent on genomic DNA isolation. A quick method for isolating and subjectively determining the presence of genomic DNA from blood, dried blood spot (DBS), and rapid diagnostic test (RDT), was identified.

Methods

We have developed a protocol for isolating DNA from blood, DBS, and RDTs using the HUDSON Buffer (TCEP and EDTA). Isolated genomic DNA was seen with SYBR Safe DNA stain (1X) under a UV transilluminator without running in 0.8 percent gel electrophoresis or using a spectrophotometer.

Results

The technique for DNA isolation was accurate for the presence of malaria parasite genomic DNA from positive samples confirmed by microscopy with a sensitivity of 76% and specificity of 78.67% and RDT with a sensitivity of 88% and specificity of 66%. The requirements were minimal, and the process took 30 minutes for a hundred sample processing.

Interpretation & conclusion

Finding a fast and reliable method of separating nucleic acids from many samples is crucial. This approach extracts intact genomic DNA in under ten minutes, making it ideal for large-scale investigations.

Rapid and ratiometric fluorescent detection of hypochlorite by glutathione functionalized molybdenum disulfide quantum dots

We proposed a rapid and ratiometric fluorescent detection method for hypochlorite by glutathione functionalized molybdenum disulfide quantum dots (G-MoS₂ QDs). The G-MoS₂ QDs were obtained through a hydrothermal method and the maximum fluorescence intensity was obtained at 430 nm under excitation of 360 nm. The fluorescence of G-MoS₂ QDs at 430 nm can be weakened by curcumin through the inner filter effect, meanwhile the fluorescence of curcumin at 540 nm appeared. Hypochlorite can fast oxidize curcumin and weaken the inner filter effect, thus the fluorescence of curcumin at 540 nm decreased and the fluorescence of G-MoS₂ QDs at 430 nm increased. This process takes only 30 s at room temperature. This is the rationale behind our rapid ratiometric fluorescent detection model for hypochlorite. Two linear detection ranges for hypochlorite are obtained with concentration from 1 to 20 μM and 20 to 30 μM, the limit of detection (LOD) was 11.5 nM. The standard spike recovery tests on milk and tap water samples showed satisfactory results, which extended the application of G-MoS₂ QDs in the field of ratiometric fluorescence detection assays.

Impedimetric nano-collision Escherichia coli analysis based on Silver-Gold bimetallic nanoparticles

An impedimetric detection of E. coli was developed using chemically synthesised bimetallic Ag-Au (1:2) nanoparticles (NPs). The UV-visible spectra of the NPs had absorption bands at 470 and 580 nm for Ag NPs and Au NPs, respectively. In the presence of E. coli, a negative potential shift and a blue shift was observed in the voltammograms and spectra respectively. The complex formed had an oxidation potential at + 0.95 V. Technique choice was based on sensitivity comparison of Differential pulse voltammetry, cyclic voltammetry and impedance spectroscopy in 0.1 M PBS with Impedance being the best choice. Optimum sensing conditions of the NPs-E. coli complex for NPs concentration, incubation period, method modulation amplitude and applied potential were 5 mM, 20 min, 10 mV and + 0.5 V, respectively. The sensor's linearity range, lower limits of detection and quantification were found to be 10¹-10⁷, 1.88 × 10¹, 2.34 × 10² cells/mL, respectively. The sensor's applicability was validated by repeatability, stability and selectivity studies showing minimum changes in signal. Potential usage of the sensor in real samples was demonstrated by standard addition analysis of sea and River water samples as well as recovery of spiked water and fruit juices with acceptable % RSD < 2%.

Rapid, sensitive, and specific detection of SARS-CoV-2 in nasopharyngeal swab samples of suspected patients using a novel one-step loop-mediated isothermal amplification (one-step LAMP) technique

BACKGROUND

In the absence of effective antiviral drugs or vaccines, early and accurate detection of SARS-CoV-2 infection is essential to the COVID-19 pandemic. This study developed and evaluated a novel rapid One-Step LAMP assay to directly detect the SARS-CoV-2 RNA from nasopharyngeal (NP) swab samples of patients with suspected SARS-CoV-2 infection living in deprived areas in comparison to One-Step Real-time PCR.

METHODS

Two hundred fifty-four NP swab samples from patients suspected of COVID-19 infection living in deprived western areas of Iran were tested by TaqMan One-Step RT-qPCR and fast One-Step LAMP assays. Tenfold serial dilutions of SARS-CoV-2 RNA standard strain where the viral copy number in each dilution was previously determined using the qPCR and various templates were used to investigate the analytical sensitivity and specificity of the One-Step LAMP assay in triplicate. Also, the efficacy and reliability of the method compared to TaqMan One-Step RT-qPCR were evaluated using SARS-CoV-2 positive and negative clinical samples.

RESULTS

The results of the One-Step RT-qPCR and One-Step LAMP tests were positive in 131 (51.6%) and 127 (50%) participants, respectively. Based on Cohen's kappa coefficient (κ), the agreement between the two tests was 97%, which was statistically significant (P < 0.001). The detection limit for the One-Step LAMP assay was 1 × 10¹ copies of standard SARS-CoV-2 RNA per reaction in less than an hour in triplicates. Negative results in all samples with non-SARS-CoV-2 templates represent 100% specificity.

CONCLUSIONS

The results showed that the One-Step LAMP assay is an efficient consistent technique for detecting SARS-CoV-2 among suspected individuals due to its simplicity, speed, low cost, sensitivity, and specificity. Therefore, it has great potential as a useful diagnostic tool for disease epidemic control, timely treatment, and public health protection, especially in poor and underdeveloped countries.

Rapid administration of Kcentra® during cardiopulmonary arrest

We present a case of cardiopulmonary arrest secondary to rivaroxaban related oropharyngeal hemorrhage, which required rapid intravenous (IV) push administration of 4-factor prothrombin complex concentrate (4F-PCC). Manufacturers recommend administering 4F-PCC IV at a rate of 0.12 mL/kg/min (approximately 3 units/kg/min) up to a maximum rate of 8.4 mL/min (approximately 210 units/min) [1]. The concern with rapid administration is increased potential for thromboembolic complications. There have been small studies assessing infusion rates greater than the manufacturer's recommendation with few reported thromboembolic events [2-5]. Our patient was an 81-year-old female presenting to the emergency department (ED) with sudden onset oropharyngeal hemorrhage. The patient had a pertinent history of oral and esophageal cancer and was prescribed rivaroxaban 20 mg once daily for treatment of deep vein thrombosis. Within moments of the patient arriving, she produced a large volume of blood from her nose and mouth. The source of the bleeding could not be determined, and as suctioning was attempted to clear her airway, the patient became unresponsive and pulseless. Advanced Cardiac Life Support (ACLS) procedures were initiated and 1000 mg of tranexamic acid were administered. Once the patient's active medication list was discovered, 2000 units of 4F-PCC was given as an IV push over roughly 20 s. Bleeding was controlled enough to secure the patient's airway within 5 min after 4F-PCC administration and subsequently return of spontaneous circulation was achieved. Unfortunately, the patient suffered a poor neurologic outcome and the family withdrew care after discussion with the treatment team and the patient's oncologist. This case report demonstrates rapid administration of 4F-PCC may be an effective intervention to treat immediately life threatening rivaroxaban related bleeding.

Reverse transcription recombinase-aided amplification assay for H5 subtype avian influenza virus

Background

The H5 subtype avian influenza virus (AIV) has caused huge economic losses to the poultry industry and is a threat to human health. A rapid and simple test is needed to confirm infection in suspected cases during disease outbreaks.

Methods

In this study, we developed a reverse transcription recombinase-aided amplification (RT-RAA) assay for the detection of H5 subtype AIV. Assays were performed at a single temperature (39 °C), and the results were obtained within 20 min.

Results

The assay showed no cross-detection with Newcastle disease virus or infectious bronchitis virus. The analytical sensitivity was 10³ RNA copies/μL at a 95% confidence interval according to probit regression analysis, with 100% specificity. Compared with published reverse transcription quantitative real-time polymerase chain reaction assays, the κ value of the RT-RAA assay in 420 avian clinical samples was 0.983 (p < 0.001). The sensitivity for avian clinical sample detection was 97.26% (95% CI, 89.56–99.52%), and the specificity was 100% (95% CI, 98.64–100%).

Conclusions

These results indicated that our RT-RAA assay may be a valuable tool for detecting H5 subtype AIV.

The Impact of the Rate of Weight Loss on Body Composition and Metabolism

PURPOSE OF REVIEW

Weight loss has multiple beneficial effects on body composition and metabolism, but whether these depend on the rate at which body weight is lost is not clear. We analyzed data from studies in which the same amount of weight loss was induced rapidly or gradually.

RECENT FINDINGS

Thirteen studies were included in which the same percentage weight loss was achieved at slow or fast rates (range: 0.2 to 3.2 kg/week) by means of dietary calorie restriction, exercise, and bariatric surgery. Faster rates of weight loss may result in more fat-free mass and less fat mass being lost during the dynamic phase of weight reduction compared with slower rates of weight loss, in conjunction with greater declines in resting energy expenditure. However, these differences are attenuated after 2-4 weeks of stabilization at the new, lower body weight, and do not affect the rate and amount of weight regain 9-33 months later (nor the tissue composition of regained weight). Differences in waist circumference, visceral and liver fat contents, resting blood pressure, fasting blood lipid profile, and insulin and adipokine concentrations in response to different rates of weight loss are trivial. The decline in fasting glucose concentration and the improvement in insulin sensitivity after 6-11% weight loss are both greater with rapid than gradual weight loss, but not different after 18-20% weight loss. Changes in body composition and metabolism after losing the same amount of body weight at different rates are largely similar, and occasional differences are likely not meaningful clinically for the long-term management of obesity and cardiometabolic diseases.

A novel rapid LAMP test for identification of cutaneous leishmaniasis: An evaluation and comparative analysis of three molecular methods

Leishmaniasis is a neglected and widespread parasitic disease that can lead to serious health problems. The conventional method in diagnostic health clinics is direct smear preparation of the lesion and staining with standard Giemsa to visualize the amastigote stage and by culturing the organism in an NNN (Novy-MacNeal-Nicolle) to observe the promastigote form of the parasite. In the case of urban-type leishmaniasis, microscopic diagnosis is sometimes not possible due to the reduction of amastigotes in patients' wounds. Because most endemic areas are located in regions that do not have access to laboratories equipped with molecular tools, access to a rapid test to diagnose the disease is essential. In this study, for the first time for DNA extraction, the scalpel used for sampling was washed and extracted by boiling method. Also, the LAMP technique in this study was modified so that the test can be performed in 10 minutes and the results can be recognized by color. We used four microscopic methods, conventional PCR, real-time PCR, and LAMP, to diagnose urban-type leishmaniasis and compared the results of these methods with each other. The sensitivity and specificity of LAMP were higher than other techniques used. Therefore, it allows rapid diagnosis for timely treatment of the disease to control the primary reservoir host more quickly in ACL as humans are the principal source of infection. This test is performed at a high-speed and is cost-effective. For its convenience, this test is highly recommended to be used in endemic areas.

A new automated and putatively versatile synthesis of the PSMA-ligand derivative [18F]DCFPyL using the FASTlabTM synthesizer

Background

Noninvasive molecular imaging using peptides and biomolecules labelled with positron emitters has become important for detection of cancer and other diseases with PET (positron emission tomography). The positron emitting radionuclide fluorine-18 is widely available in high yield from cyclotrons and has favorable decay (t_1/2 109.7 min) and imaging properties. ¹⁸F-Labelling of biomolecules and peptides for use as radiotracers is customarily achieved in a two-step approach, which can be challenging to automate. 6-[¹⁸F]Fluoronicotinic acid 2,3,5,6-tetrafluorophenyl ester ([¹⁸F]F-Py-TFP) is a versatile ¹⁸F-prosthetic group for this purpose, which can be rapidly be produced in an one-step approach on solid support. This work details an automated procedure on the cassette-based GE FASTlab™ platform for the labeling of a peptidomimetic, exemplified by the case of using the Glu-CO-Lys motif to produce [¹⁸F]DCFPyL, a ligand targeting the prostate specific membrane antigen (PSMA).

Results

From fluorine-18 delivery a fully automated two-step radiosynthesis of [¹⁸F]DCFPyL was completed in 56 min with an overall end of synthesis yield as high as 37% using solid phase extraction (SPE) purification on the GE FASTlab™ platform.

Conclusions

Putatively, this radiolabeling methodology is inherently amenable to automation with a diverse set of synthesis modules, and it should generalize for production of a broad spectrum of biomolecule-based radiotracers for use in PET imaging.

The Coris BioConcept COVID 19 Ag Respi-Strip, a field experience feedback

This communication described how the Coris BioConcept COVID-19 Ag Respi-Strip test (Coris-Ag) was implemented in the workflow of our clinical microbiology laboratory for COVID-19 diagnosis. The diagnostic performance statistics (sensitivity, specificity) of the Coris-Ag were evaluated against a gold standard, the RealStar SARS-CoV-2 RT-PCR kit 1.0. Additionally, the effect of reading the Coris-Ag results at 30 min was compared to reading at 15 min. The Coris-Ag was performed on a total of 294 patients during two periods; 158 patients were tested during period 1 at the peak of the pandemic (April 6th to April 10th 2020) which returned a positivity rate of 17.1 %, and 136 patients during period 2 (April 12th to April 16th 2020) which returned a positivity rate of 11 %. Compared to the RT-PCR, the 15-minute Coris-Ag readings resulted in a sensitivity of 59.3 % with a 100 % specificity for the period 1 patients (n = 158) while the sensitivity decreased to 20 % for the period 2 patients (n = 136). The overall sensitivity was 38.1 % for both periods (n = 294). The corresponding 30-minute readings produced a 7 % increase in sensitivity with a specificity of 100 % (n = 294). The sensitivity of the strip test (15-min reading) for high viral loads (Ct <25) was 84.6 %.

Rapid quantitative analysis of hormones in serum by multilayer paper spray MS: Free MS from HPLC

Developing rapid and reliable method for simultaneous hormones quantitation is of great significant because of important roles of hormones in metabolism. However, current methods are faced with problems of low throughput or complicated operation procedure to remove matrices from serum samples in routine clinical diagnosis. In the present work, a multilayer PS-MS method was developed for rapid and simple detection of hormones. In the strategy, multilayer filter paper acted as the Liquid Chromatography in LC-MS/MS for separation of hormones and biological matrices. Qualitative and quantitative analysis of three hormones, testosterone (T), androsterone (ADT) and androstenedione (4-AD) were realized through MS/MS spectra. The method exhibited linearity in the range of 0.02-2 μg/L and the results of recovery and repeatability were satisfactory for standard samples and spiked serum. The time-cost of a whole detection process was less than 3 min. The established multilayer PS-MS realized rapid, simple and reliable quantitative analysis of various hormones and provided broad prospect for clinical analysis of small molecules in different biological samples. Moreover, it provides a novel MS approach with high through-put and free HPLC, meeting the requirements of point-of-care testing (POCT).

Rapid antigen tests for the detection of SARS-CoV-2: A narrative review

The rapid identificationand isolation of COVID-19 patients has become the cornerstone for the control of the recent outbreak. Real-time quantitative polymerase chain reaction is routinely used to confirm COVID-19 diagnosis and is considered the gold standard due to high sensitivity and specificity. Nevertheless, it usually takes several days and a relatively higher cost. Antigen tests based have emerged to cope with such disadvantages, by offering rapid results, an easy-to-use procedure, and low costs. The objective of the narrative review was to provide up-to-date data about CE-marked rapid antigen tests (RATs) for COVID-19. Given their large number, the study only focused on representative and widely used in Spain (Standard Q, Nadal, Panbio, CerTest, and Wondfo). RATs have become a very useful and validated tool for controlling the spread of COVID-19 allowing the rapid identification of active infection and isolation of positive patients. The present revision of the literature has demonstrated that sensitivity and specificity of all available RATs in Spain are high and accomplish European regulations and WHO recommendations.

Evaluation of the rCIM for carbapenemase detection in Enterobacterales and Pseudomonas aeruginosa and description of the TSBrCIM, an optimized variant

OBJECTIVES

The rapid Carbapenem Inactivation Method (rCIM) was evaluated with a strain collection of 164 and 69 carbapenem-resistant Enterobacterales and Pseudomonas aeruginosa, respectively, that produced various carbapenemases. For an improved carbapenemase detection in Enterobacterales, an optimized variant of the rCIM named TSBrCIM was developed.

METHODS

Bacterial isolates were incubated with two meropenem disks in distilled water (rCIM) or tryptic soy broth (TSBrCIM). After centrifugation, the supernatant was incubated with a susceptible E. coli indicator strain in tryptic soy broth. Growth of the indicator strain implied carbapenemase activity in the test strain.

RESULTS

The rCIM detected 100/113 carbapenemase-producing Enterobacterales, resulting in a sensitivity of 88.5% and a specificity of 94.1%. For P. aeruginosa, sensitivity and specificity were 96.0% and 100%, respectively. The TSBrCIM was able to detect 105/113 carbapenemase-producing Enterobacterales, resulting in a sensitivity of 92.9% and a specificity of 96.1%.

CONCLUSION

This study shows that the TSBrCIM can be valuable tool for detection of carbapenemases in Enterobacterales in the clinical laboratory, while the rCIM showed the best results for carbapenemase detection in P. aeruginosa.

A method for high-throughput image-based antifungal screening

Robust antifungal screening is technically challenging particularly for filamentous fungi. We present a method for undertaking antifungal screening assays that builds upon existing broth dilution protocols and incorporates time resolved image-based assessment of fungal growth. We show that the method performs with different fungi, particularly those for which spores can be used as inoculum, and with different compound classes, can accurately assess susceptibility or otherwise in only few hours and can even account for differences in inherent growth properties of strains.

Evaluation of infrared assisted freeze drying for strawberry snacks: drying kinetics, energy efficiency and quality attributes

Feasibility of infrared assisted freeze drying (IRAFD) was evaluated for production of the strawberry snacks. Infrared (IR) radiation provided the driving force of ice sublimation during freeze drying (FD). Different IRAFD conditions were tested, including the continuous IRAFD-1.6 kW/m² and IRAFD-1.6 kW/m² at different weight reductions (20%, 40%, and 60%). Conventional FD had a total drying time of 691 ± 19 min, whereas continuous IRAFD significantly reduced the drying time to 309 ± 32 min. Continuous IRAFD also reduced the amount of consumed electrical energy by 42% compared to that of FD. A long duration of IR radiation produced a soft texture in the snacks. Drying kinetics were analyzed using various models, including the Page model, exponential model, and Henderson and Pabis model. The Page model provided the best fit to the experimental drying curve. This study showed the potential of IRAFD in producing value-added fruit snacks with good textural quality and efficient use of energy.

Evaluation of a modified rapid viability-polymerase chain reaction method for Bacillus atrophaeus spores in water matrices

A rapid method that provides information on the viability of organisms is needed to protect public health and ensure that remediation efforts following a release of a biological agent are effective. The rapid viability-polymerase chain reaction (RV-PCR) method combines broth culture and molecular methods to provide results on whether viable organisms are present in less than 15 h. In this study, a modified RV-PCR (mRV-PCR) method was compared to a membrane-filtration culture method for the detection of viable Bacillus spores in water matrices. Samples included small and large volumes of chlorine and non‑chlorine treated tap water. Large volume water samples (up to 100 L), were processed by ultrafiltration using a semi-automated waterborne pathogen concentrator, followed by centrifugation as a secondary concentration technique. The concentrated samples were analyzed by mRV-PCR and culture methods. The overall agreement between the mRV-PCR and culture methods when seed concentrations were greater than 10 spores per sample volume analyzed was 96%. The total time from the start of sample processing to the final sample result for the mRV-PCR method was decreased by approximately 2 h, in comparison to the previously published RV-PCR method because of the incorporation of shorter, more efficient primary and secondary concentration steps and a shorter DNA extraction technique. Overall, this study confirmed that RV-PCR is a promising approach for identifying viable Bacillus spores in small- and large-volume water samples and for producing results in less time than traditional culture methods.

Changes over time in latent patterns of childhood-to-adulthood BMI development in Great Britain: evidence from three cohorts born in 1946, 1958, and 1970

BACKGROUND

Most studies on secular trends in body mass index (BMI) are cross-sectional and the few longitudinal studies have typically only investigated changes over time in mean BMI trajectories. We aimed to describe how the evolution of the obesity epidemic in Great Britain reflects shifts in the proportion of the population demonstrating different latent patterns of childhood-to-adulthood BMI development.

METHODS

We used pooled serial BMI data from 25,655 participants in three British cohorts: the 1946 National Survey of Health and Development (NSHD), 1958 National Child Development Study (NCDS), and 1970 British Cohort Study (BCS). Sex-specific growth mixture models captured latent patterns of BMI development between 11 and 42 years. The classes were characterised in terms of their birth cohort composition.

RESULTS

The best models had four classes, broadly similar for both sexes. The 'lowest' class (57% of males; 47% of females) represents the normal weight sub-population, the 'middle' class (16%; 15%) represents the sub-population who likely develop overweight in early/mid-adulthood, and the 'highest' class (6%; 9%) represents those who likely develop obesity in early/mid-adulthood. The remaining class (21%; 29%) reflects a sub-population with rapidly 'increasing' BMI between 11 and 42 years. Both sexes in the 1958 NCDS had greater odds of being in the 'highest' class compared to their peers in the 1946 NSHD but did not have greater odds of being in the 'increasing' class. Conversely, males and females in the 1970 BCS had 2.78 (2.15, 3.60) and 1.87 (1.53, 2.28), respectively, times higher odds of being in the 'increasing' class.

CONCLUSIONS

Our results suggest that the obesity epidemic in Great Britain reflects not only an upward shift in BMI trajectories but also a more recent increase in the number of individuals demonstrating more rapid weight gain, from normal weight to overweight, across the second, third, and fourth decades of life.

A simple magnetic-assisted microfluidic method for rapid detection and phenotypic characterization of ultralow concentrations of bacteria

Isolation and enumeration of bacteria at ultralow concentrations and antibiotic resistance profiling are of great importance for early diagnosis and treatment of bacteremia. In this work, we describe a simple, rapid, and versatile magnetic-assisted microfluidic method for rapid bacterial detection. The developed method enables magnetophoretic loading of bead-captured bacteria into the microfluidic chamber under external static and dynamic magnetic fields in 4 min. A shallow microfluidic chamber design that enables the monolayer orientation and transportation of the beads and a glass substrate with a thickness of 0.17 mm was utilized to allow high-resolution fluorescence imaging for quantitative detection. Escherichia coli (E. coli) with green fluorescent protein (GFP)-expressing gene and streptavidin-modified superparamagnetic microbeads were used as model bacteria and capturing beads, respectively. The specificity of the method was validated using Lactobacillus gasseri as a negative control group. The limit of detection and limit of quantification values were determined as 2 CFU/ml and 10 CFU/ml of E. coli, respectively. The magnetic-assisted microfluidic method is a versatile tool for the detection of ultralow concentrations of viable bacteria with the linear range of 5-5000 CFU/ml E. coli in 1 h, and providing growth curves and phenotypic characterization bead-captured E. coli in the following 5 h of incubation. Our results are promising for future rapid and sensitive antibiotic susceptibility testing of ultralow numbers of viable cells.

Rapid prioritisation of topics for rapid evaluation: the case of innovations in adult social care and social work

BACKGROUND

Prioritisation processes are widely used in healthcare research and increasingly in social care research. Previous research has recommended using consensus development methods for inclusive research agenda setting. This research has highlighted the need for transparent and systematic methods for priority setting. Yet there has been little research on how to conduct prioritisation processes using rapid methods. This is a particular concern when prioritisation needs to happen rapidly. This paper aims to describe and discuss a process of rapidly identifying and prioritising a shortlist of innovations for rapid evaluation applied in the field of adult social care and social work.

METHOD

We adapted the James Lind Alliance approach to priority setting for rapid use. We followed four stages: (1) Identified a long list of innovations, (2) Developed shortlisting criteria, (3) Grouped and sifted innovations, and (4) Prioritised innovations in a multi-stakeholder workshop (n = 23). Project initiation through to completion of the final report took four months.

RESULTS

Twenty innovations were included in the final shortlist (out of 158 suggested innovations). The top five innovations for evaluation were identified and findings highlighted key themes which influenced prioritisation. The top five priorities (listed here in alphabetical order) were: Care coordination for dementia in the community, family group conferencing, Greenwich prisons social care, local area coordination and MySense.Ai. Feedback from workshop participants (n = 15) highlighted tensions from using a rapid process (e.g. challenges of reaching consensus in one workshop).

CONCLUSION

The method outlined in this manuscript can be used to rapidly prioritise innovations for evaluation in a feasible and robust way. We outline some implications and compromises of rapid prioritisation processes for future users of this approach to consider.

Rapid and sensitive detection of melanin using glutathione conjugated gold nanocluster based fluorescence quenching assay

In the present study, a rapid, facile, and highly sensitive assay based on glutathione conjugated gold nanocluster (GSH-AuNCs) is developed for the detection of melanin. The analysis of melanin which is linked to several diseases is crucial. The current methods for melanin estimation are complex and long, thus demands an alternative technology. In general, melanin exhibits photoactive properties, thus, it might have fluorescence quenching properties through the phenomenon of fluorescence resonance energy transfer. To verify our assumption, we have developed the fluorescence quenching assay based on gold nanocluster and melanin interaction. As a result, under the optimized condition, the developed quenching assay demonstrated the high selectivity and sensitivity toward melanin with a limit of detection and correlation coefficient of 0.060 μg/mL and 0.993, respectively. Moreover, the whole process represented the rapid assay time of 30 min to complete. To validate the performance of our assay on real samples, B16F1 cells lysate, and hair samples were tested that provided satisfactory results. Therefore, we believe that our assay due to good sensitivity and short assay time could be beneficial for the clinical diagnosis of melanin in the future study.

An inexpensive retrospective standard setting method based on item facilities

BACKGROUND

Standard setting is one of the most challenging aspects of assessment in high-stakes healthcare settings. The Angoff methodology is widely used, but poses a number of challenges, including conceptualisation of the just-passing candidate, and the time-cost of implementing the method. Cohen methodologies are inexpensive and rapid but rely on the performance of an individual candidate. A new method of standard setting, based on the entire cohort and every item, would be valuable.

METHODS

We identified Borderline candidates by reviewing their performance across all assessments in an academic year. We plotted the item scores of the Borderline candidates in comparison with Facility for the whole cohort and fitted curves to the resulting distribution.

RESULTS

It is observed that for any given Item, an equation of the form y ≈ C. e^Fx where y is the Facility of Borderline candidates on that Item, x is the observed Item Facility of the whole cohort, and C and F are constants, predicts the probable Facility for Borderline candidates over the test, in other words, the cut score for Borderline candidates. We describe ways of estimating C and F in any given circumstance, and suggest typical values arising from this particular study: that C = 12.3 and F = 0.021.

CONCLUSIONS

C and F are relatively stable, and that the equation y = 12.3. e^0.021x can rapidly be applied to the item Facility for every item. The average value represents the cut score for the assessment as a whole. This represents a novel retrospective method based on test takers. Compared to the Cohen method which draws on one score and one candidate, this method draws on all items and candidates in a test. We propose that it can be used to standard set a whole test, or a particular item where the predicted Angoff score is very different from the observed Facility.

A rapid GC method coupled with quadrupole or time of flight mass spectrometry for metabolomics analysis

Gas chromatography-mass spectrometry (GC-MS) is an ideal tool for analyzing the intermediates of tricarboxylic acid cycle and glycolysis, sugars, organic acids and amino acids, etc. High-throughput metabolomics methods are required by large-scale clinical researches, and time of flight mass spectrometry (TOF MS) having fast scanning rate is preferable for rapid GC. Quadrupole MS (qMS) instruments have 95% market share, and their potential in rapid metabolomics is worth being studied. In this work, a within 15-min GC program was established and matched by qMS scanning for plasma metabolome analysis after N-methyl-N-(trimethylsilyl)-trifluoroacetamide derivatization. Compared to the longer-time program GC-qMS method, the rapid GC-qMS method had nearly no metabolome information loss, and it had excellent profile performance in repeatability, intra-day and inter-day precision, sampling range, linearity and extraction recovery. Compared to TOF MS, qMS achieved similar results in investigating lung cancer serum metabolic disruptions. Partial least squares-discriminant analysis revealed that the two datasets acquired by qMS and TOF MS had very similar model parameters, and most of top ranked differential metabolites were the same. This study provides a rapid and economical GC-qMS metabolomics method for researchers. Still, MS having faster scanning rate and higher sensitivity are recommended, if possible, to detect more small peaks and some co-eluted peaks.

Mini review: Recent progress in RT-LAMP enabled COVID-19 detection

The coronavirus disease 2019 (COVID-19) pandemic has infected millions of people around the globe. The outbreak caused by the novel coronavirus (SARS-CoV-2) poses a great health risk to the public. Therefore, rapid and accurate diagnosis of the virus plays a crucial role in treatment of the disease and saving lives. The current standard method for coronavirus detection is the reverse transcription polymerase chain reaction (RT-PCR) method. However, laboratory-based RT-PCR test for SARS-COV-2 requires complex facilities and elaborate training of operators, thus suffering from limit testing capacity and delayed results. Consequently, isothermal PCR such as loop-mediated isothermal amplification (LAMP) has been emerging as a great alternative to the RT-PCR method. LAMP possesses some fundamental advantages such as amplification at a constant temperature, exclusion of a thermal cycler, a faster test result, and potentially a larger diagnostic capacity, while maintaining similar sensitivity and specificity, thus making it more suitable than the RT-PCR for monitoring a pandemic. Starting with a brief introduction of the working principle of LAMP method, this review summarizes recent progress in LAMP-enabled SARS-CoV-2 viral RNA detection. Lastly, future research directions are discussed. This critical review will motivate biosensor community in furthering the present research, which may pave the road for rapid and large-scale screening of SARS-CoV-2.

Rapid progression of carotid stenosis was rare in a large integrated healthcare system during an eight-year period

OBJECTIVE

Few studies have evaluated the rapid progression of carotid stenosis on a large scale. We created a custom software algorithm to analyze an electronic medical record database to examine the natural progression of carotid stenosis, identify a subset of patients with rapid progression, and evaluate the specific patient risk factors associated with this rapid progression.

METHODS

Patients in a large integrated healthcare system who had undergone two or more carotid ultrasound scans from August 2010 to August 2018 were identified. We did not distinguish between those with an established carotid stenosis diagnosis and those with a screening ultrasound scan. We used our novel algorithm to extract data from their carotid ultrasound reports. The degrees of carotid stenosis were categorized as follows: level 1, 0% to 39%; level 2, 40% to 59%; level 3, 60% to 79%; level 4, 80% to 99%; and level 5, complete occlusion. The primary endpoint was rapid vs slow progression of carotid stenosis, with rapid progression defined as an increase of two or more levels within any 18-month period of the study, regardless of the date of the initial ultrasound scan. The association of the demographic and clinical characteristics with rapid progression was assessed by univariable and multivariable logistic regression.

RESULTS

From a cohort of 4.4 million patients, we identified 4982 patients with two or more carotid ultrasound scans and a median follow-up period of 13.1 months (range, 0.1-93.7 months). Of the 4982 patients, 879 (17.6%) had shown progression of carotid stenosis. Only 116 patients (2.3%) had had progression to level 4 (80%-99% stenosis) from any starting level during a median of 11.5 months. A total of 180 patients (3.6%) were identified as experiencing rapid progression during a median follow-up of 9.9 months. The final multivariable analysis showed that younger age (P < .01), white race (P = .02), lower body mass index (P = .01), a diagnosis of peripheral arterial disease (P = .03), and a diagnosis of transient ischemic attack (P < .01) were associated with rapid progression.

CONCLUSIONS

Using a novel algorithm to extract data from >4 million patient records, we found that rapid progression of carotid stenosis appears to be rare. Although 17.6% of patients showed any degree of progression, only 3.6% had experienced rapid progression. Among those with any disease progression, 20.5% had experienced rapid progression. Although the overall incidence of rapid progression was low, patients with any progression might warrant close follow-up, especially if they have the associated risk factors for rapid progression. The custom software algorithm might be a powerful tool for creating and evaluating large datasets.

The Evolving Role of the Clinical Microbiology Laboratory in Identifying Resistance in Gram-Negative Bacteria: An Update

The evolution of resistance to antimicrobial agents in gram-negatives has challenged the role of the clinical microbiology laboratory to implement new methods for their timely detection. Recent development has enabled the use of novel methods for more rapid pathogen identification, antimicrobial susceptibility testing, and detection of resistance markers. Commonly used methods improve the rapidity of resistance detection from both cultured bacteria and specimens. This review focuses on the commercially available systems available together with their technical performance and possible clinical impact.

An integrated target recognition and polymerase primer probe for microRNA detection

Extremely sensitive and visual measurements of microRNA (miRNA) in situ for early detection and monitoring of diseases remains a major challenge. To address this issue, this work reports a rapid, highly sensitive and selective microRNA (miRNA) biosensing strategy based on isothermal circular strand-displacement polymerization (ICSDP), and miRNA imaging was performed inside cells. In this work, a double hairpin DNA probe (HP1/HP2 complex) embedded with a sensing region and polymerase primer region was designed. Briefly, after the specific binding of target miRNA with the HP1/HP2 probe, HP1/HP2 itself can function as a primer to initiate the ICSDP with the help of Klenow Fragment (KF), yielding target miRNA for new rounds of ICSDP. In this process, one target can produce multiple signal outputs (1: n), achieving low abundance of miRNA detection. Under optimized conditions, the proposed strategy showed high sensitivity with a detection limit of 5 pM within 15 min and can also easily distinguish the control miRNA from the target miRNA. This method can be further applied to image the intracellular miRNA of interest in situ inside the cancer cells.

Rapid detection of Enterobacterales that produce carbapenemases

PURPOSE

The rapid detection of carbapenemases among Enterobacterales in clinical laboratories is critical for management of patients, and infection prevention and control efforts.

METHODS

A study was designed to evaluate the performances of the RAPIDEC CARBA NP®, β-CARBA®, NG-Test CARBA 5®, modified carbapenem-inactivation method, and EDTA version (eCIM) assays against a global collection of Enterobacterales (n = 216) with diverse carbapenemases.

RESULTS

The RAPIDEC CARBA NP® assay had a sensitivity of 98.6% and specificity of 19.6% and β-CARBA® a sensitivity of 94% and specificity of 97.8%, but showed low sensitivity with Klebsiella Pneumoniae Carbapenemase (KPC)-containing isolates. The NG-Test CARBA 5® had an overall sensitivity of 96.3% and specificity of 100% and failed to detect isolates with bla_IMP-13, bla_IMP-14. The eCIM gave false- positive results with Oxacillinase (OXA)-48-like enzymes.

CONCLUSION

The NG-Test CARBA 5® assay was technically simple and provided rapid accurate results on the types of carbapenemases. Such information has potential treatment benefits for patients.

Predicting antioxidant activity of wood vinegar using color and spectrophotometric parameters

Wood vinegar can be produced from many types of raw materials using different pyrolysis methods resulting in potentially different antioxidant activity. Therefore, this study developed a rapid method to predict the antioxidant activity of wood vinegar based on color using the CIELAB system and spectrophotometric parameters. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP) exhibited significant correlations with the L* and b* values of the color parameters and the UV absorbance polyphenol index (I280), European Brewing Convention (EBC) and Institute of Brewing (IOB) color units, color intensity and Linner Hue index of the spectrophotometric parameters. As a result, DPPH radical scavenging activity and FRAP could be predicted by measuring color and spectrophotometric parameters. Overall, this study provide a simple, rapid and no chemical reaction involved method to predict antioxidant activity. Furthermore, models with a set of spectrophotometric parameters could be used to predict antioxidant activities. •Whole new method for predicting wood vinegar antioxidant activity was developed.•The method was models developed by using color and spectrophotometric parameters used in beverage industry.•The models were simple, rapid and involved no chemical reaction.

A clinic-based direct real-time fluorescent reverse transcription loop-mediated isothermal amplification assay for influenza virus

Seasonal influenza virus causes acute respiratory tract infections, which can be severe in children and the elderly. At present, rapid influenza diagnostic tests (RIDTs) are popular at clinical sites because they enable early diagnosis and avoid unnecessary use of antibiotics; in addition, high risk patients with underlying disease can be given antiviral drugs. However, the sensitivity and specificity of some of those tests are relatively poor. To overcome these problems, nucleic acid-based molecular point-of-care tests have been developed; however, they are significantly more expensive than RIDTs. Previously, the authors developed real-time reverse transcription loop-mediated isothermal amplification (rRT-LAMP) assays using a quenching primer to detect influenza viruses. However, the assay is limited to laboratory use because it requires a nucleic acid purification step and preparation of reaction mixtures on ice. Therefore, the authors developed and validated direct rRT-LAMP assays that require no nucleic acid purification steps using commercial RNA isolation kits, and no storage and handling of reagents on ice. These assays can be performed within 10-30 min and require only mixing a clinical specimen with extraction reagent followed by addition of a lyophilized detection reagent. The established assay showed high sensitivity and specificity when validated using 310 clinical specimens. Thus, the assay is a powerful tool for molecular diagnosis of seasonal influenza virus infection in the clinic.

Molecular method for rapid detection of the red tide dinoflagellate Karenia mikimotoi in the coastal region of Xiangshan Bay, China

The species Karenia mikimotoi is a common nearshore red tide alga that can secrete hemolytic exotoxin and ichthyotoxin, which can induce the death of fish and shellfish, causing severe economic losses. In this study, loop-mediated isothermal amplification (LAMP) was employed in combination with the lateral flow dipstick (LFD) visual detection method to establish the LAMP-LFD rapid detection method for K. mikimotoi. The internal transcribed spacer ITS1-5.8S-ITS2 of K. mikimotoi was used as the target sequence and was amplified with specific primers designed in this study. The results indicated that the amplification optimal reaction conditions for LAMP in this paper were for 20 min at 65 °C. Moreover, LAMP had excellent specificity, showing negative results for other common red tide causing algal species. In field samples, we successfully reduced the total time, with only 23 min needed from LAMP amplification to LFD result display, which was shorter than that of conventional PCR. Consequently, LAMP-LFD should be useful for rapid field detection of low-density K. mikimotoi and for the early prevention of red tide induced by such algae.

Biomarkers of Infection and Sepsis

The role of biomarkers for detection of sepsis has come a long way. Molecular biomarkers are taking front stage at present, but machine learning and other computational measures using bigdata sets are promising. Clinical research in sepsis is hampered by lack of specificity of the diagnosis; sepsis is a syndrome with no uniformly agreed definition. This lack of diagnostic precision means there is no gold standard for this diagnosis. The final conclusion is expert opinion, which is not bad but not perfect. Perhaps machine learning will displace expert opinion as the final and most accurate definition for sepsis.

Rapid multiplex microfiber-based immunoassay for anti-MERS-CoV antibody detection

On-site multiplex biosensors for innate immunity antibodies are ideal tools for monitoring health status of individuals against various diseases. This study introduces a novel antibody immunoassay testing platform incorporating microfiber-based arrays of antigens to capture specific antibodies. The fabrication and setup of the device revolved around electrospun polystyrene (ESPS) microfibers that act as three-dimensional membrane filters, capable of rapid and multifold analyte capture. In particular, the ESPS microfibers were patterned through localized oxygen plasma to create hydrophilic zones that facilitate fluid flows and immobilizations of antigens. The bulk of this robust antibody immunoassay platform could be installed into a compact syringe-driven cassette device, which could perform multiplex antibody immunoassay for antibodies specifically against Middle East respiratory syndrome coronavirus (MERS-CoV) with rapid preparation amounting to a total of 5 min, as well as high sensitivity and specificity for the MERS-CoV down to 200 μg/mL.

Nongenomic glucocorticoid effects and their mechanisms of action in vertebrates

Glucocorticoids (GC) act on multiple organ systems to regulate a variety of physiological processes in vertebrates. Due to their immunosuppressive and anti-inflammatory actions, glucocorticoids are an attractive target for pharmaceutical development. Accordingly, they are one of the most widely prescribed classes of therapeutics. Through the classical mechanism of steroid action, glucocorticoids are thought to mainly affect gene transcription, both in a stimulatory and suppressive fashion, regulating de novo protein synthesis that subsequently leads to the physiological response. However, over the past three decades multiple lines of evidence demonstrate that glucocorticoids may work through rapid, nonclassical mechanisms that do not require alterations in gene transcription or translation. This review assimilates evidence across the vertebrate taxa on the diversity of nongenomic actions of glucocorticoids and the membrane-associated cellular mechanisms that may underlie rapid glucocorticoid responses to include potential binding sites characterized to date.

Evaluation of a new rapid fluorescence immunoassay for the diagnosis of dengue and Zika virus infection

BACKGROUND

Dengue (DENV) and Zika virus (ZIKV) are important mosquito-transmitted viruses.

OBJECTIVES

To investigate the performance of Standard F, Fluorescence Immunoassay (FIA, SD Biosensor Inc., Suwon, South Korea) providing results in 15 min to detect DENV IgG, IgM and NS1Ag, and ZIKV IgG, IgM, and Ag.

STUDY DESIGN

A well-characterized panel of patient samples (11 acute DENV, 11 acute ZIKV, 10 past DENV, 10 past ZIKV infection, 36 with other conditions) were tested with the FIA test.

RESULTS

In acute DENV infection, the combination of FIA-NS1Ag and/or IgM positivity showed a sensitivity of 100%. In past DENV, FIA-IgG test showed a sensitivity of 70%. Specificity of FIA-DENV NS1Ag, IgG, and IgM was 87.5%, 83.5%, and 91.7%, respectively. The sensitivity of FIA-ZIKV IgM and FIA-ZIKV Ag, in confirmed acute infection, was 72.7% and 9.1%, respectively. FIA-ZIKV Ag did not improve the sensitivity in detecting acute ZIKV infection, being positive only in one IgM positive sample. In past ZIKV infection (32-183 days after symptom onset), FIA-ZIKV IgG and IgM showed a sensitivity of 40% and 80% respectively, generating an overall 90% sensitivity. Specificity of FIA-ZIKV Ag, IgM, and IgG was 92.6%, 100%, and 97%, respectively.

CONCLUSION

FIA test, a rapid and easy to perform assay, showed high sensitivity to detect acute DENV infection, but lower in acute ZIKV infection. In past ZIKV infections, the best performance of FIA test is obtained by combining detection of IgG and IgM.

Rapid Screening of CRISPR/Cas9-Induced Mutants Using the ACT-PCR Method

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system provides a technological breakthrough in targeted mutagenesis. However, a significant amount of time and cost is required to screen for the CRISPR/Cas9-induced mutants from a typically large number of initial samples. Here, we describe a cost-effective and sensitive screening technique based on conventional polymerase chain reaction (PCR), termed "annealing at critical temperature PCR" (ACT-PCR), for identifying mutants. ACT-PCR requires only a single PCR step followed by agarose gel electrophoresis. The simplicity of ACT-PCR makes it particularly suitable for rapid, large-scale screening of CRISPR/Cas9-induced mutants.

Prospective gating control for highly efficient cardio-respiratory synchronised short and constant TR MRI in the mouse

PURPOSE

Cardiac and respiratory motion derived image artefacts are reduced when data are acquired with cardiac and respiratory synchronisation. Where steady state imaging techniques are required in small animals, synchronisation is most commonly performed using retrospective gating techniques but these invoke an inherent time penalty. This paper reports the development of prospective gating techniques for cardiac and respiratory motion desensitised MRI with significantly reduced minimum scan time compared to retrospective gating.

METHODS

Prospective gating incorporating the automatic reacquisition of data corrupted by motion at the entry to each breath was implemented in short TR 3D spoiled gradient echo imaging. Motion sensitivity was examined over the whole mouse body for scans performed without gating, with respiratory gating, and with cardio-respiratory gating. The gating methods were performed with and without automatic reacquisition of motion corrupted data immediately after completion of the same breath. Prospective cardio-respiratory gating, with acquisition of 64 k-space lines per cardiac R-wave, was used to enable whole body DCE-MRI in the mouse.

RESULTS

Prospective cardio-respiratory gating enabled high fidelity steady state imaging of physiologically mobile organs such as the heart and lung. The automatic reacquisition of data corrupted by motion at the entry to each breath minimised respiratory motion artefact and enabled a highly efficient data capture that was adaptive to changes in the inter-breath interval. Prospective cardio-respiratory gating control enabled DCE-MRI to be performed over the whole mouse body with the acquisition of successive image volumes every 12-15 s at 422 μm isotropic resolution.

CONCLUSIONS

Highly efficient cardio-respiratory motion desensitised steady state MRI can be performed in small animals with prospective synchronisation, centre-out phase-encode ordering, and the automatic reacquisition of data corrupted by motion at the entry to each breath. The method presented is robust against spontaneous changes in the breathing rate. Steady state imaging with prospective cardio-respiratory gating is much more efficient than with retrospective gating, and enables the examination of rapidly changing systems such as those found when using DCE-MRI.

Point of Care Policy for Eliminating Hepatitis C, its Applicability and Acceptability

Chronic infection with hepatitis C virus (HCV), can now be safely treated with oral, well-tolerated medications with >90% success rates, however, currently <5% of the infected individuals have been diagnosed and <1% have received treatment. This is believed to be due to the complicated, time-consuming and expensive disease management processes that require several referrals to specialized laboratories and hospital-based clinics, and also the epidemic of HCV infection among populations who have low uptake for evaluation, appointments, and treatment. Point of care (POC) policy emphasizes on delivering healthcare tests and services to patients at or near the place and time of patient care. A reasonable design for POC policy should contain all parts of the HCV management continuum including screening, diagnosis of viremia, genotyping, cirrhosis evaluation and treatment. Furthermore, successful implementation of this policy requires acceptability from the perspectives of healthcare providers, target populations, and policymakers. In this letter, we discuss the current applicability, acceptability, and cost-effectiveness of POC policy for the management of HCV infection.

Comparison of Rapid Centrifugation Technique with Conventional Centrifugation for Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT) Testing

Prothrombin Time (PT) and activated partial thromboplastin time (APTT) are frequently performed coagulation tests in patients with coagulation disorders especially in critical care areas and in monitoring patients on anticoagulation therapy. In coagulation testing, sample processing especially centrifugation is one of the most critical steps that affect turnaround time (TAT). This study was carried out over a period of 1 year. Three hundred paired samples from patients sent for PT and APTT estimation were included. One sample was centrifuged in a regular bench top centrifuge at 1500g for 20 min. The other sample was divided into two polypropylene aliquots and centrifuged in a microcentrifuge at 13000g for 3 min. The plasma obtained from both methods was tested for PT and APTT using the automated method on STA Compact coagulometer (Stago) using commercial thromboplastin STA^R-Neoplastine^R C1 Plus and phospholipid (cephalin), STA^R-C K PREST^R 5 respectively. Data were analyzed using descriptive statistics, Student t test, correlation coefficient and Bland-Altman plots. Mean PT, INR and APTT for both centrifugation methods was comparable with no statistically significant difference (p > 0.05). PT, INR and APTT also showed good correlation (r > 0.98) when compared between the two methods of centrifugation. Bland-Altman comparison between rapid and conventional methods of centrifugation for PT, INR and APTT also showed acceptable agreement. Rapid centrifugation technique for routine coagulation testing can be used safely with a significant reduction in the TAT. This can benefit patients in critical care settings and those on outpatient oral anticoagulant therapy.

Homologous alignment cloning: a rapid, flexible and highly efficient general molecular cloning method

Homologous alignment cloning (HAC) is a rapid method of molecular cloning that facilitates low-cost, highly efficient cloning of polymerase chain reaction products into any plasmid vector in approximately 2 min. HAC facilitates insert integration due to a sequence alignment strategy, by way of short, vector-specific homology tails appended to insert during amplification. Simultaneous exposure of single-stranded fragment ends, utilising the 3′→5′ exonuclease activity of T4 DNA polymerase, creates overlapping homologous DNA on each molecule. The exonuclease activity of T4 polymerase is quenched simply by the addition of EDTA and a simple annealing step ensures high yield and high fidelity vector formation. The resultant recombinant plasmids are transformed into standard E. coli cloning strains and screened via established methods as necessary. HAC exploits reagents commonly found in molecular research laboratories and achieves efficiencies that exceed conventional cloning methods, including another ligation-independent method we tested. HAC is also suitable for combining multiple fragments in a single reaction, thus extending its flexibility.

An ambient temperature stable and ready-to-use loop-mediated isothermal amplification assay for detection of toxigenic Vibrio cholerae in outbreak settings

Cholera, caused by Vibrio cholerae is a foodborne disease that frequently reported in food and water related outbreak. Rapid diagnosis of cholera infection is important to avoid potential spread of disease. Among available diagnostic platforms, loop-mediated isothermal amplification (LAMP) is regarded as a potential diagnostic tool due to its rapidity, high sensitivity and specificity and independent of sophisticated thermalcycler. However, the current LAMP often requires multiple pipetting steps, hence is susceptible to cross contamination. Besides, the strict requirement of cold-chain during transportation and storage make its application in low resource settings to be inconvenient. To overcome these problems, the present study is aimed to develop an ambient-temperature-stable and ready-to-use LAMP assay for the detection of toxigenic Vibrio cholerae in low resource settings. A set of specific LAMP primers were designed and tested against 155 V. cholerae and non-V. cholerae strains. Analytical specifity showed that the developed LAMP assay detected 100% of pathogenic V. cholerae and did not amplified other tested bacterial strains. Upon testing against stool samples spiked with toxigenic V. cholerae outbreak isolates, the LAMP assay detected all of the spiked samples (n = 76/76, 100%), in contrast to the conventional PCR which amplified 77.6% (n = 59/76) of the tested specimens. In term of sensitivity, the LAMP assay was 100-fold more sensitive as compared to the conventional PCR method, with LOD of 10 fg per μL and 10 CFU per mL. Following lyophilisation with addition of lyoprotectants, the dry-reagent LAMP mix has an estimated shelf-life of 90.75 days at room temperature.

CCD Camera Detection of HIV Infection

Rapid and precise quantification of the infectivity of HIV is important for molecular virologic studies, as well as for measuring the activities of antiviral drugs and neutralizing antibodies. An indicator cell line, a CCD camera, and image-analysis software are used to quantify HIV infectivity. The cells of the P4R5 line, which express the receptors for HIV infection as well as β-galactosidase under the control of the HIV-1 long terminal repeat, are infected with HIV and then incubated 2 days later with X-gal to stain the infected cells blue. Digital images of monolayers of the infected cells are captured using a high resolution CCD video camera and a macro video zoom lens. A software program is developed to process the images and to count the blue-stained foci of infection. The described method allows for the rapid quantification of the infected cells over a wide range of viral inocula with reproducibility, accuracy and at relatively low cost.

Establishment of a multiplex real-time RT-PCR assay for rapid identification of H6 subtype avian influenza viruses

The H6 subtype avian influenza viruses (AIVs) possess the capacity for zoonotic transmission from avian species to humans. Establishment of a specific, rapid and sensitive method to screen H6 AIVs is necessary. Based on the conserved domain of the matrix and H6 AIV hemagglutinin genes, two TaqMan minor-groove-binder probes and multiplex real-time RT-PCR primers were designed in this study. The multiplex real-time RT-PCR assay developed in this study had high specificity and repeatability and a detection limit of 30 copies per reaction. This rapid diagnostic method will be useful for clinical detection and surveillance of H6 AIVs in China.

Clinical decision making in the emergency department setting using rapid PCR: Results of the CLADE study group

•

The influence of an influenza diagnosis on patient managed during ED visits is examined.

•

An influenza diagnosis in the ED is actionable, impacting empiric management in 61% of cases.

•

The clinical diagnosis of influenza, based on presenting symptoms, lacks sensitivity at 36%.

•

A 30 min result from collection to report could be achieved in the ED for 91.7%, of cases tested.

•

ED testing resulted in savings of $200.40/ED visit but is dependent on avoiding planned admissions.

Background

Emergency Departments (ED) are challenged during influenza season by patients who present acutely during sporadic ED visits. ED management is largely empiric, often occurring without reliable diagnostics needed for targeted therapies, safe outpatient discharge, or hospital admissions.

Objective

To evaluate the impact of the influenza diagnosis on physician decision making during ED visits using the Cobas Liat^® influenza A + B assay.

Study design

Prospective study assessing the impact of rapid (<30 min), reverse-transcriptase polymerase chain reaction (RT-PCR) influenza testing on physician decision making in the ED. Physician responses established pre-and post-diagnosis management courses which required confirmation via secondary documentation in the medical record. Changes in physician decision making were analyzed across four clinical touchpoints: (i) admission/discharge status, (ii) medical procedures, (iii) antiviral and antibiotic prescribing, and (iv) laboratory studies.

Results

An influenza diagnosis changed patient management courses, relative to empiric, pre-diagnosis plans, in in 61% of the cases resulting in cost savings of $49,420-to-$42,270 over 143 patients and 104 days during influenza season resulting in a cost savings of $200.40/ED visit. Evaluation over 2000 ED patient visits projects cost savings > $578,000 due to deferred admissions, and reduction in antiviral prescribing. Sensitivity of ED-based influenza testing using the Cobas Liat^® assay was equivalent to centralized lab testing at 98.8% sensitivity and 98.5% specificity respectively.

Conclusion

Providing rapid, RT-PCR influenza testing to ED settings is actionable and used to guide patient care decisions. Understanding the cascade of events linked to the influenza diagnosis in the ED provides overall cost savings which offset the cost of providing ED-based testing.

An advanced uracil DNA glycosylase-supplemented loop-mediated isothermal amplification (UDG-LAMP) technique used in the sensitive and specific detection of Cryptosporidium parvum, Cryptosporidium hominis, and Cryptosporidium meleagridis in AIDS patients

The rapid and accurate detection of Cryptosporidium spp. is critically important for the prevention and timely treatment of cryptosporidiosis in AIDS patients (APs). This study was conducted to examine a UDG-LAMP technique for the first time to diagnose cryptosporidiosis in APs. After collecting demographic and clinical data, three stool samples were collected from the participants (120 volunteering APs). The microscopic examination of stained smears using the acid-fast method and the UDG-LAMP assay were performed for each sample. 10% of APs were infected with Cryptosporidium spp. The number of detected cryptosporidiosis cases using the acid-fast staining and UDG-LAMP methods were significantly different (P < 0.001). Diarrhea and weight loss were found to be significantly associated with cryptosporidiosis in patients (P < 0.05). The pretreatment of LAMP reagents with UDG successfully eliminated the likelihood of product re-amplification remaining from previous reactions. The UDG-LAMP technique could detect cryptosporidiosis in APs with high sensitivity and rapidity without carryover contamination.

The Changing Role of the Clinical Microbiology Laboratory in Defining Resistance in Gram-negatives

The evolution of resistance in Gram-negatives has challenged the clinical microbiology laboratory to implement new methods for their detection. Multidrug-resistant strains present major challenges to conventional and new detection methods. More rapid pathogen identification and antimicrobial susceptibility testing have been developed for use directly on specimens, including fluorescence in situ hybridization tests, automated polymerase chain reaction systems, microarrays, mass spectroscopy, next-generation sequencing, and microfluidics. Review of these methods shows the advances that have been made in rapid detection of resistance in cultures, but limited progress in direct detection from specimens.