Testing Laboratories Research Articles

The Contribution of Legionella anisa to Legionella Contamination of Water in the Built Environment.

Legionella bacteria can proliferate in poorly maintained water systems, posing risks to users. All Legionella species are potentially pathogenic, but Legionella pneumophila (L. pneumophila) is usually the primary focus of testing. However, Legionella anisa (L. anisa) also colonizes water distribution systems, is frequently found with L. pneumophila, and could be a good indicator for increased risk of nosocomial infection. Anonymized data from three commercial Legionella testing laboratories afforded an analysis of 565,750 water samples. The data covered July 2019 to August 2021, including the COVID-19 pandemic. The results confirmed that L. anisa commonly colonizes water distribution systems, being the most frequently identified non-L. pneumophila species. The proportions of L. anisa and L. pneumophila generally remained similar, but increases in L. pneumophila during COVID-19 lockdown suggest static water supplies might favor its growth. Disinfection of hospital water systems was effective, but re-colonization did occur, appearing to favor L. pneumophila; however, L. anisa colony numbers also increased as a proportion of the total. While L. pneumophila remains the main species of concern as a risk to human health, L. anisa's role should not be underestimated, either as a potential infection risk or as an indicator of the need to intervene to control Legionella's colonization of water supplies.

A hybrid SgDT framework for risk analysis of container-handling operations at automated container terminals

With the booming maritime economy and the steady expansion of port production, automated container terminals (ACTs) have rapidly developed worldwide. The safety and stability of container-handling operations at ACTs are crucial for maintaining high efficiency and performance in maritime transportation and global supply chains. However, few studies have focused on the quantitative risk analysis of container-handling operations at ACTs. This study proposes a hybrid SgDT (STPA-grey-DEMATEL-TAISM) approach to analyze risk factors and their coupling interrelationships within ACT handling operations. Initially, 22 factors influencing ACT handling operations were identified based on the system theoretic process analysis (STPA) model and literature. Subsequently, grey theory and decision-making test and evaluation laboratory (DEMATEL) were fused to visualize the cause-effect relationships of these factors. Finally, the total adversarial interpretive structural model (TAISM) was adopted to extract the hierarchical interrelationships among these factors using an adversarial hierarchical structure. The findings showed that poor supervision, communication network failures, sensor malfunctions, equipment malfunctions, lack of safety awareness, and interruptions of the power supply are the most critical factors influencing ACT handling operations. This study provides theoretical insights and practical implications for managers to enhance ACT handling risk management.

Comparative Evaluation of Commercial Test Kits Cleared for Use in Modified Two-Tiered Testing Algorithms for Serodiagnosis of Lyme Disease.

Modified 2-tiered testing (MTTT) for Lyme disease utilizes automatable, high throughput immunoassays (AHTIs) in both tiers without involving western immunoblots, offering performance and practical advantages over standard 2-tiered testing (STTT; first-tier AHTI followed by immunoglobulin M (IgM) and immunoglobulin G (IgG) western immunoblots). For MTTT, Centers for Disease Control and Prevention recommends using AHTI test kits that have been cleared by Food and Drug Administration (FDA) specifically for this intended use. We evaluated performance of FDA-cleared MTTT commercial test kits from 3 manufacturers by comparing with STTT results. We performed MTTT (total antibody AHTI with reflex to separate IgM and IgG AHTIs) using test kits from Diasorin, Gold Standard Diagnostics (GSD), and Zeus Scientific on 382 excess serum samples submitted to the clinical laboratory for routine Lyme disease serologic testing in July 2018, measuring agreement between MTTT and STTT using the κ statistic. Overall agreement with STTT was 0.87 (95% confidence interval [CI], .77-.97) using Diasorin assays (almost perfect agreement), 0.80 (95% CI, .68-.93) using GSD assays (substantial agreement) and 0.79 (95% CI, .68-.90) using Zeus assays (substantial agreement). For detection of IgM reactivity, agreement between MTTT and STTT was 0.70 (.51-.90; substantial), 0.63 (95% CI, .44-.82; substantial) and 0.56 (95% CI, .38-.73; moderate), respectively. For detection of IgG reactivity, MTTT/STTT agreement was 0.73 (95% CI,.58-.88), 0.78 (95% CI, .62-.94), and 0.75 (95% CI, .60-.90), respectively (substantial agreement in all cases). MTTT results obtained using commercial test kits from 3 different manufacturers had substantial to almost perfect agreement with STTT results overall and moderate to substantial agreement for IgM and IgG detection independently. Commercial MTTT tests can be used broadly for the diagnosis of Lyme disease.

Comprehensive FRP-concrete bond behavior: Impact of test methods and the innovative UBoT

The lack of a standardized bond test method for fiber-reinforced polymer (FRP)-concrete interfaces leads to variations in forms of the popular single-lap shear, double-lap shear, beam, mixed-mode, and pull-off tests. Recognizing the limitations of each bond test technique and the importance of analyzing all results as complementary, a detailed evaluation of these variations is essential for accurate bond behavior assessment prior to design and field deployment, to avoid subjective decisions and predictions. This study pioneers the evaluation of FRP-concrete bond test methods, offering the industry a consistent dataset for informed decision-making. Single- and double-lap shear tests yield trilinear bond-slip responses; however, the single-lap test’s lack of symmetry reduces bond strength by 15% compared to the double-lap test. The beam test, unsuitable for bond-slip modeling, shows comparable average bond strength to the single- and double-lap tests. The mixed-mode test better simulates field applications, while the pull-off test provides the most consistent results. Given that each test method reflects only one field scenario, the Universal Bond Tester (UBoT) was developed. This device can convert to all FRP-concrete bond test types. It also addresses the modified double-lap shear test’s limitations (e.g., inapplicability to pultruded laminate and FRP rupture in wet layup systems) and present a modified ASTM D7958 beam and mixed-mode tests cost-effectively. The UBoT captures full bond behavior and variabilities, overcoming the limitations of existing methods which fail to capture all failure modes in bond-critical applications. It reduces specimen sizes, weight, and data acquisition needs by half for most tests. This study allows test laboratories to use any preferred testing method with the UBoT. Link to video demonstrations for all tested specimens are provided in the supplementary material.

Burden of rare genetic disorders in India: twenty-two years’ experience of a tertiary centre

BackgroundRare disorders comprise of ~ 7500 different conditions affecting multiple systems. Diagnosis of rare diseases is complex due to dearth of specialized medical professionals, testing labs and limited therapeutic options. There is scarcity of data on the prevalence of rare diseases in different populations. India being home to a large population comprising of 4600 population groups, of which several thousand are endogamous, is likely to have a high burden of rare diseases. The present study provides a retrospective overview of a cohort of patients with rare genetic diseases identified at a tertiary genetic test centre in India.ResultsOverall, 3294 patients with 305 rare diseases were identified in the present study cohort. These were categorized into 14 disease groups based on the major organ/ organ system affected. Highest number of rare diseases (D = 149/305, 48.9%) were identified in the neuromuscular and neurodevelopmental (NMND) group followed by inborn errors of metabolism (IEM) (D = 47/305; 15.4%). Majority patients in the present cohort (N = 1992, 61%) were diagnosed under IEM group, of which Gaucher disease constituted maximum cases (N = 224, 11.2%). Under the NMND group, Duchenne muscular dystrophy (N = 291/885, 32.9%), trinucleotide repeat expansion disorders (N = 242/885; 27.3%) and spinal muscular atrophy (N = 141/885, 15.9%) were the most common. Majority cases of β-thalassemia (N = 120/149, 80.5%) and cystic fibrosis (N = 74/75, 98.7%) under the haematological and pulmonary groups were observed, respectively. Founder variants were identified for Tay-Sachs disease and mucopolysaccharidosis IVA diseases. Recurrent variants for Gaucher disease (GBA:c.1448T > C), β-thalassemia (HBB:c.92.+5G > C), non-syndromic hearing loss (GJB2:c.71G > A), albinism (TYR:c.832 C > T), congenital adrenal hyperplasia (CYP21A2:c.29–13 C > G) and progressive pseudo rheumatoid dysplasia (CCN6:c.298T > A) were observed in the present study.ConclusionThe present retrospective study of rare disease patients diagnosed at a tertiary genetic test centre provides first insight into the distribution of rare genetic diseases across the country. This information will likely aid in drafting future health policies, including newborn screening programs, development of target specific panel for affordable diagnosis of rare diseases and eventually build a platform for devising novel treatment strategies for rare diseases.

The efficacy of integrated vermifiltration technology for treatment of food analysis laboratory wastewater

The macrophyte-assisted vermifiltration (MAVF) technology was applied for treatment of food analysis laboratory wastewater at Industrial Technology Institute (ITI), Sri Lanka for the first time. Three laboratory-scale sub-surface vertical flow units were established:1) without earthworms and plants (Control unit), 2) with earthworms (Eisenia fetida) (vermi-filtration unit (VF unit), 3) with both earthworms and macrophytes (Canna indica) (MAVF unit). Wastewater was fed batch-wise with a feeding rate of 10 mL/min and seven days hydraulic retention time (HRT) for eight consecutive batches. Physiochemical parameters, Chemical Oxygen Demand (COD), Total Phosphorus (TP), Total Nitrogen (TN), pH, of the influent and effluent of all three units were analyzed to investigate the treatment efficiencies. One-Way ANOVA was performed to evaluate the significant differences in treatment efficiencies. The mean COD removal efficiencies of the control unit, VF unit, and MAVF unit were 60.2 % ± 10.7, 71.6± 8.07 %, and 72.0 % ± 8.86, respectively. Average TN removal efficiencies of the control unit, VF unit, and MAVF unit were 8.05 % ± 5.75, 10.9±6.4 %, and 24.9 % ±12.84, respectively. Average TP removal efficiencies were 35.84 % ± 17.5, 35.84 % ± 17.5 %, and 40.0 % ±16.76, respectively. The COD removal displayed promising results, whereas the means for enhancing TP and TN removal should be further studied. The findings of this study sensitizes the testing laboratories to go green by adopting in-house cost effective laboratory wastewater treatment systems.

Development of Ecotourism Scenario Based on Seawater Quality Evaluation

There were various activities in the Bungkutoko Island Kali Biru Bathing area by PT. Pelindo Nusantara and community settlements can unwittingly impact the quality of the water environment. This study aimed to determine the quality of seawater in the Kali Biru bathing area and develop a sustainable tourism-based environmental engineering concept. This research method uses surveys and laboratory analysis. Examination of water samples is carried out directly. Seawater analysis is descriptive with quality data from the results of water quality tests in testing laboratories whose feasibility levels were determined based on Indonesia's government rule number 22 of 2012. The results showed that three elements had laboratory test values exceeding the threshold value, namely: nitrite (NO2-N), sulfate (SO4), and iron (Fe), which should not be present, but during the study, there were already values for nitrite (NO2-N) of 0.12, 0.006, and 0.0006, sulfate (SO4) of 2.3, 1.4, and 4.8 and iron (Fe) of 0.0012, 0.0019, and 0.001 while the other six elements starting from pH (degree of acidity), salinity (%), nitrate (NO3-N), oil and grease, arsenic (As), and total coliform were within the regional quality threshold sea tourism. Scenarios for developing tourism activities through ecotourism activities.

Whole-genome sequencing for antimicrobial surveillance: species-specific quality thresholds and data evaluation from the network of the European Union Reference Laboratory for Antimicrobial Resistance genomic proficiency tests of 2021 and 2022.

As antimicrobial resistance (AMR) surveillance shifts to genomics, ensuring the quality of whole-genome sequencing (WGS) data produced across laboratories is critical. Participation in genomic proficiency tests (GPTs) not only increases individual laboratories' WGS capacity but also provides a unique opportunity to improve species-specific thresholds for WGS quality control (QC) by repeated resequencing of distinct isolates. Here, we present the results of the EU Reference Laboratory for Antimicrobial Resistance (EURL-AR) network GPTs of 2021 and 2022, which included 25 EU national reference laboratories (NLRs). A total of 392 genomes from 12 AMR-bacteria were evaluated based on WGS QC metrics. Two percent (n = 9) of the data were excluded, due to contamination, and 11% (n = 41) of the remaining genomes were identified as outliers in at least one QC metric and excluded from computation of the adjusted QC thresholds (AQT). Two QC metric correlation groups were identified through linear regression. Eight percent (n = 28) of the submitted genomes, from 11 laboratories, failed one or more of the AQTs. However, only three laboratories (12%) were identified as underperformers, failing across AQTs for uncorrelated QC metrics in at least two genomes. Finally, new species-specific thresholds for "N50" and "number of contigs > 200 bp" are presented for guidance in routine laboratory QC. The continued participation of NRLs in GPTs will reveal WGS workflow flaws and improve AMR surveillance data. GPT data will continue to contribute to the development of reliable species-specific thresholds for routine WGS QC, standardizing sequencing data QC and ensure inter- and intranational laboratory comparability.IMPORTANCEIllumina next-generation sequencing is an integral part of antimicrobial resistance (AMR) surveillance and the most widely used whole-genome sequencing (WGS) platform. The high-throughput, relative low-cost, high discriminatory power, and rapid turnaround time of WGS compared to classical biochemical methods means the technology will likely remain a fundamental tool in AMR surveillance and public health. In this study, we present the current level of WGS capacity among national reference laboratories in the EU Reference Laboratory for AMR network, summarizing applied methodology and statistically evaluating the quality of the obtained sequence data. These findings provide the basis for setting new and revised thresholds for quality metrics used in routine WGS, which have previously been arbitrarily defined. In addition, underperforming participants are identified and encouraged to evaluate their workflows to produce reliable results.

Etiology, risk factors and antibiotic resistance in neonatal sepsis.

Objective: To determine the etiology, risk factors and antibiotic resistance in neonatal sepsis. Study Design: Cross-sectional study. Setting: Department of Pediatric Medicine, National Institute of Child Health, Karachi, Pakistan. Period: October 2023 to March 2024. Methods: A total of 174 neonates of both genders, with suspected neonatal sepsis were analyzed. Neonatal and maternal characteristics were noted. Blood sample was collected in aseptic environment and sent to institutional laboratory for blood culture and drug susceptibility testing. Results: In a total of 174 neonates, 101 (58.0%) were boys. The mean age, and weight were 9.61±7.86 years, and 2.25±0.85 kg, respectively. Neonatal sepsis on the basis of positive blood culture was reported in 38 (21.8%) neonates. Preterm birth had significant association with neonatal sepsis (44.7% vs. 26.5%, p=0.019). History of maternal UTI during pregnancy had significant linkage with neonatal sepsis (36.8% vs. 11.0%, p<0.001). History of maternal fever during pregnancy had statistically significant association with neonatal sepsis (34.2% vs/ 19.1%, p=0.049). E. Coli, and Klebsiella were the most commonly found bacterial isolates, noted in 8 (21.1%), and 4 (10.5%) neonates, respectively. Most commonly used antimicrobial drugs were found to have high resistance rates against most frequent bacterial isolates. Conclusion: E. Coli, and Klebsiella were the most commonly found bacterial isolates in neonatal sepsis. Preterm birth, maternal history of UTI, and maternal history of fever were found to be significant factors linked to neonatal sepsis. Most commonly used antimicrobial drugs were found to have high resistance patterns which should raise alarms.

TakeMeHome: A Novel Method for Reaching Previously Untested People Through Online Ordering and Self-Collect HIV and STI Testing.

Despite national testing guidelines, rates of testing for HIV, sexually transmitted infections (STIs), and hepatitis C remain lower than recommended for men who have sex with men in the United States. To help address this, the TakeMeHome (TMH) program was started in March 2020 by Building Healthy Online Communities, a consortium of public health organizations and dating apps, to work with health departments to increase access to HIV testing for men who have sex with men on dating apps. Users of participating dating apps were sent messages about opportunities for testing with self-collected specimens through TMH. Program users were eligible to receive test kits if they lived in a participating zip code and were aged at least 18 years. Users who were interested in testing could order kits to be mailed to them for laboratory-based testing of HIV, hepatitis C, chlamydia, gonorrhea, and/or syphilis, depending on risk and availability in their zip code. Orders were sent via application programming interface to Molecular Testing Labs for fulfillment; kits were provided at no cost to the program user. Within approximately 24 hours of order receipt, Molecular Testing Labs mailed program users a kit with required collection supplies, directions, and a link to a video instruction for self-collection. Program users received an automated email after testing was complete with a link to access results through their online account. Individuals with positive results on any of the relevant tests were directed to additional information and to local providers for linkage to additional testing or treatment, depending on local protocols. The positivity rate of specimens processed through TMH was 1.4% for HIV, 0.6% for hepatitis C, and 2.9% for all STIs combined. The per-person positivity rate was 15.3% across all STIs. The TMH program demonstrates that self-collected laboratory-processed testing is feasible and effective at identifying new HIV and STI cases.

Preface of the proceeding of 12th International Symposium on Current Research in Hydropower Technologies

Current Research in Hydropower Technologies, CRHT-XII conference is taking place at Kathmandu University every year since 2012. It is an annual event of Turbine Testing Lab, where researchers and students in the field of hydraulic turbines and hydropower technologies share their experiences and research outcomes in a common platform. The event used to take place among the Masters and PhD students of Kathmandu University and Norwegian University of Science and Technology. However, there has also been an active participation from researchers and students around the world who are engaged in the similar fields in recent times. The conference has now taken an international recognition, as the selected papers from this conference will be published in journal proceedings. This year in the conference, 37 papers were presented in the topics of hydraulic turbines and pumps, computational and experimental techniques, hydropower and other renewable energy technologies, as well as the problems of erosion and cavitations. This year, we also saw many papers in the field of fish migration, fish passing technologies in hydropower, tunnel engineering and EV technologies, which show the broad topics covered within the hydropower. After receiving comments from the presentations and a peer review process, 24 papers have been selected for publication in this proceeding. We hope that the papers will be beneficial for the researchers and students involved in the sector of hydropower. We would like to thank all the participants, organizing team and the technical committee for the valuable contributions to make this a successful event. Editors Sailesh Chitrakar, PhD (sailesh@ku.edu.np) Prajwal Sapkota (prajwal.sapkota@ku.edu.np)

Vibrational Analysis on Cooling Fan with Induced Mechanical Faults

Abstract This paper reports the investigation of different mechanical faults such as unbalanced loading, broken blades, and deformed blades induced in a fan using vibration analysis. The fan used in this study was a CPU cooling fan as a representation of a basic fan system giving an idea of vibration signatures when it is subjected to faults conditions. This study assists in developing the techniques of condition monitoring for the diagnosis of failures and faults in fan systems while logging the operating status and trend in performance. The investigation is carried out in the turbine testing lab using a Tri-axial accelerometer and a commercial Intel® CPU cooling fan consisting of 7 blades. The fan was run at different RPMs with normal and fault conditions like unbalanced loading conditions induced by adding mass of different weights, breakage of blades, deformation of blades, and holes in the blades. These faults are induced to simulate various mechanical faults that frequently occur in fan-based systems. The vibration data obtained from the accelerometer are filtered and the time series of acceleration values are plotted using MATLAB. For further analysis of data, the Fast Fourier Transform is done to evaluate the peaks of vibration signals in normal and fault conditions. Vibrational amplitude in fault conditions like Hole-2 has 4.5 times higher amplitude than normal and Cut-2 has 31.5 times higher amplitude.

Scalable approaches for generating, validating and incorporating data from high-throughput functional assays to improve clinical variant classification

As the adoption and scope of genetic testing continue to expand, interpreting the clinical significance of DNA sequence variants at scale remains a formidable challenge, with a high proportion classified as variants of uncertain significance (VUSs). Genetic testing laboratories have historically relied, in part, on functional data from academic literature to support variant classification. High-throughput functional assays or multiplex assays of variant effect (MAVEs), designed to assess the effects of DNA variants on protein stability and function, represent an important and increasingly available source of evidence for variant classification, but their potential is just beginning to be realized in clinical lab settings. Here, we describe a framework for generating, validating and incorporating data from MAVEs into a semi-quantitative variant classification method applied to clinical genetic testing. Using single-cell gene expression measurements, cellular evidence models were built to assess the effects of DNA variation in 44 genes of clinical interest. This framework was also applied to models for an additional 22 genes with previously published MAVE datasets. In total, modeling data was incorporated from 24 genes into our variant classification method. These data contributed evidence for classifying 4043 observed variants in over 57,000 individuals. Genetic testing laboratories are uniquely positioned to generate, analyze, validate, and incorporate evidence from high-throughput functional data and ultimately enable the use of these data to provide definitive clinical variant classifications for more patients.

Inconsistencies between prenatal diagnostic and genetic testing laboratories on variant validation of rare monogenic diseases.

The advent of next-generation sequencing (NGS) has enhanced the diagnostic efficacy for monogenic diseases, while presenting challenges in achieving consistent diagnoses. We retrospectively analyzed the concordance rate and reasons for the inconsistency between the original diagnostic result from the genetic testing laboratory and the variant validation result from the prenatal diagnostic center. The validation procedure comprised three stages: validation of variant detection, reevaluation of variant classification, and assessment of recurrence risk, which involved verifying the mode of inheritance and parental carriage. In total, 17 (6%) of the 286 families affected by rare monogenic diseases showed different results during the variant validation procedure. These cases comprised four (23.5%) with variant detection errors, 12 (70.5%) with inconsistent interpretation, and one (6%) with non-Mendelian inheritance patterns. False-positive NGS results confirmed by Sanger sequencing were related to pseudogenes and GC-rich regions. The classification of the 17 variants was altered in the 12 cases owing to various factors. The case with an atypical inheritance pattern was originally considered autosomal recessiveinheritance, but was diagnosed as maternal uniparental disomy after additional genetic analysis. We underscored the significance of variant validation by prenatal diagnostic centers. Families affected by monogenic diseases with reproductive plans should be referred to prenatal genetic centers as early as possible to avoid different results that may postpone subsequent prenatal diagnosis.

Biochemical indicators, quality and safety of domestic and wild pig slaughter products

Animal husbandry is one of the important branches of agricultural production, which plays an important role in the formation of food security of Ukraine and providing the population with important types of food. The correct methodical approach to the inspection of organs and tissues of slaughtered animals allows to avoid errors in the diagnosis of various diseases, in the sanitary assessment of slaughter products, to prevent meat losses and the release of food products that are dangerous for humans. Analyzing the requirements of the modern market and the priority directions for the development of trade relations between the countries of the European Union for our country, it should be noted that the responsibility for the export and import of products of animal origin and the control of the production of high-quality and safe products is entrusted to the specialist of the state veterinary service. Organoleptic analysis of slaughter products is an important component of inspection. In addition, it should be noted that determining the degree of freshness of meat for a long time was carried out only with the help of the organoleptic method. It has been proven that organoleptic indicators provide comprehensive information for determining the good quality of meat. The quality of meat or its nutritional value refers to the chemical composition of the fleshy part, which includes muscle, fat and connective tissue. The chemical composition, energy value, digestibility, taste, culinary and other properties of meat depend on the ratio of these tissues. The quality of meat is influenced by the breed of animals, sex, age, fatness, the nature of fattening, conditions of transportation and pre-slaughter aging, methods of stunning, degree of exsanguination, etc. The article presents materials related to the inspection of animal slaughter products in the Zhytomyr region (agro-food market in the city of Olevsk). The study was carried out as part of the research work of the department of normal and pathological morphology, hygiene and expertise “Monitoring the content of toxic substances in drinking water, feed and their impact on the body of cattle and the quality and safety of products”, state registration number – 0120U101318. The purpose of the study is to inspect the slaughter products of domestic and wild pigs in the agro-food market of the Zhytomyr region. The task of the work was to determine the organoleptic, physico-chemical and microbiological indicators of slaughter products of domestic and wild pigs. The testing laboratory of veterinary and sanitary examination in the market carries out significant work on the inspection of animal slaughter products, which ensures the release of good-quality products for the population. As a result of the inspection of the slaughter products of domestic and wild pigs, it was established that all meat samples according to organoleptic parameters corresponded to the parameters of fresh high-quality meat, the reaction to peroxidase was positive, the pH of the meat ranged from 5.9 to 6.1. No trichinella was detected during trichinoscopy of pork samples. Veterinary and sanitary examination of livestock products on the markets is carried out only by veterinary medicine specialists of state laboratories or other state institutions of veterinary medicine. The laboratory carries out mandatory quality and safety control of all controlled products sold, including food products of animal origin intended for human consumption. In this regard, it is important to carry out inspection, sanitary evaluation of slaughter products of slaughter animals and determination of morphological characteristics of meat of domestic and wild pigs.

27. Somatic genomic testing and variant curation practices in Australian and New Zealand diagnostic testing laboratories

27. Somatic genomic testing and variant curation practices in Australian and New Zealand diagnostic testing laboratories

Comparison of Water and DTPA Extractants for Testing of Greenhouse Soilless Substrates

ABSTRACT The main purpose of this study was to improve the accuracy and reliability of nutrient analysis on soilless substrates by comparing two different saturated medium extract (SME) methods, using either water (SMEW) or DTPA (diethylenetriamine-pentaacetic acid, SMED) as extractants. A series of analyses were performed to compare ion levels quantified from either SMEW or SMED. Substrate pH, electrical conductivity (EC) and nutrient data were analyzed from a survey of substrate components (coconut coir, peat, bark, perlite, vermiculite), and blended greenhouse propagation substrates using the SMEW and SMED methods. In addition, a series of SMEW and SMED extracted samples were sent to three commercial soil testing laboratories for nutrient analysis. The objectives of these analyses were to (1) validate that published relationships between SMEW and SMED methods were consistent with correlation curves for pH, EC and nutrient levels across a wide range of soilless substrates, (2) compare statistical variability of results from SMEW and SMED methods and (3) compare variability in results between different laboratories. The results validated that previously published standards for interpreting SMEW extractions can be used for SMED method for macronutrients and EC due to an approximately 1:1 relationship for test results between extraction methods. Up to 2 orders of magnitude higher levels of micronutrients were extracted for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) using SMED compared with SMEW, with low correlation between extractants. Concentrations of ions from SMED extractions were less variable than SMEW for micronutrient analysis but were comparable for macronutrient analysis. Results from this study were combined with published research to provide suggested ranges using SMED for soilless substrates.

Comparative Evaluation of Colistin-Susceptibility Testing in Carbapenem-Resistant Klebsiella pneumoniae Using VITEK, Colistin Broth Disc Elution, and Colistin Broth Microdilution.

The study aimed to compare the results of colistin-susceptibility testing performed using the automated VITEK system, colistin broth microdilution (BMD), and colistin broth disk elution (CBDE) methods. This exploratory study was conducted in a tertiary care center in South India. Carbapenem-resistant Klebsiella pneumoniae (n = 49) isolates collected from a clinical microbiology laboratory over six months (March-September 2023) were used for the study. Among the 49 carbapenem-resistant Klebsiella pneumoniae isolates, 42 were found to be susceptible to carbapenem by all three methods. Seven isolates were found to be resistant to colistin using BMD and CBDE methods. Two isolates were incorrectly detected as colistin-susceptible, and one isolate was wrongly categorized as colistin-resistant using the automated VITEK system. CBDE is a reliable and cost-effective method that can be adopted in the routine microbiology laboratory for colistin-susceptibility testing, as it does not require any specialized equipment or techniques and is 100% consistent with the gold standard BMD method. Although the automated VITEK system is used in most routine microbiological laboratories for antibiotic-susceptibility testing, it cannot be reliably used for colistin-susceptibility testing due to its high error rates (very major error rate of 28.5%; major error rate of 2.4%).

Challenges of Integrating Artificial Intelligence into Testing Laboratories

Challenges of Integrating Artificial Intelligence into Testing Laboratories

Comparative assessment of three commercial kits and in house optimized PCR assays for GMO screening in food and feed

Screening strategies for GMO detection in food and feed are a crucial aspect in GMO testing laboratories for streamlining the analytical workflow and reducing turnaround time and costs. These strategies can be more or less complex or even be targeted according to the ingredients in the product, but whatever the choice, a good basic approach is generally based on the search for 35S promoter (P35S), nos-terminator (T-nos) and FMV promoter (P-FMV). In this study, we compare the singleplex real time PCR method for P35S, T-nos and P-FMV detection currently adopted by the Italian National Reference Laboratory for GM food and feed (NRL) with three commercial kits available on the market for giving a greater choice to consider the best approach suitable to the official control laboratories that are different from each other.•The NRL optimized singleplex PCR methods and the three commercial kits fully respect all the validation parameters criteria according to the minimum performance requirements (MPR) of ENGL [1]•Screening strategies for GMO detection in food and feed are a crucial aspect in GMO testing laboratories and being the commercial kits different from each other, the laboratory can choose the methods best suit their needs reducing turnaround time and costs.