Commercial Methods Research Articles

Performance of Guava Stem Cutting – A Review of Successful Though Non-commercial Propagation Method

Propagation of Guava (Psidium guajava L.) can be successfully performed by stem cutting as demonstrated by many researchers time to time. Though, guava is found hard to root, use of root inducing hormone (IBA, IAA, NAA etc.), rejuvenating techniques (fungicide, wounding, Girdling etc.), growth supporting media (silt, Sand, cocopeat, vermicompost, vermiculite etc.) and suitable protected environment (mist house, polyhouse, net house etc.) ease the rooting of cutting. Despite of the fact that propagation through cutting is easiest and most convenient method of vegetative propagation to regenerate numerous planting materials in short duration, wedge grafting is still recommended as commercial method of propagation in Guava. This scenario raises the question on potentiality of stem cutting as viable propagation method. This might be due to complex mechanism behind guava stem cutting propagation which results in inconsistent and highly variable results. Moreover, propagation involves multiple factors which have combined influence on the performance of stem cutting viz., preparation of cutting, preconditioning treatment, season of taking cutting, type of cutting, chemical treatment, growing environment, growing media and container. Therefore, to establish guava stem cutting as viable and commercial propagation technique, in depth study of these factors is vital. This paper briefly discusses the research so far has done with relevance to various factors influencing performance of guava stem cutting while indicating possible future research directions for more encouraging and consistent results.

Continuous Lithium‐Ion Extraction From Seawater and Mine Water With a Fuel Cell System and Ceramic Membranes

The demand for electronic devices that utilize lithium is steadily increasing in this rapidly advancing technological world. Obtaining high‐purity lithium in an environmentally friendly way is challenging by using commercialized methods. Herein, we propose the first fuel cell system for continuous lithium‐ion extraction using a lithium superionic conductor membrane and advanced electrode. The fuel cell system for extracting lithium‐ion has demonstrated a twofold increase in the selectivity of Li+/Na+ while producing electricity. Our data show that the fuel cell with a titania‐coated electrode achieves 95% lithium‐ion purity while generating 10.23 Wh of energy per gram of lithium. Our investigation revealed that using atomic layer deposition improved the electrode's uniformity, stability, and electrocatalytic activity. After 2000 cycles determined by cyclic voltammetry, the electrode preserved its stability.

CRISPR/Cas12a and aptamer-chemiluminescence based analysis for the relative abundance determination of tumor-related protein positive exosomes for breast cancer diagnosis

Exosomes, as novel biomarker for liquid biopsy, exhibit huge important potential value for cancer diagnosis. However, various proteins show different expression levels on exosomal membrane, and the absolute concentration of exosomes in clinical samples is easily influenced by a number of factors. Here, we developed a CRISPR/Cas12a and aptamer-chemiluminescence based analysis (CACBA) for the relative abundance determination of tumor-related protein positive exosomes in plasma for breast cancer diagnosis. The total concentration of exosomes was determined through captured CD63 using a CRISPR/Cas12a-based method with the LoD of 8.97 × 103 particles/μl. Meanwhile, EpCAM and MUC1 positive exosomes were quantitatively detected by aptamer-chemiluminescence (ACL) based method with the LoD of 1.45 × 102 and 3.73 × 102 particles/μl, respectively. It showed that the percentages of EpCAM and MUC1 positive exosomes offered an excellent capability to differentiate breast cancer patients and healthy donors. The high sensitivity, strong specificity, outstanding anti-interference capability, and steady recovery rate of this approach offered higher accuracy and robustness than the commercialized method in clinical trial. In addition with good stability, easy preparation and low cost, this method not only provides a new approach to rapid analysis of exosome proteins, it may be quickly extended to the diagnoses of various cancers.

Evaluation of two commercial diagnostic methods for HHV-8 viral load assessment

ObjectivesHuman herpesvirus-8 (HHV-8) can cause Kaposi's sarcoma or B lymphoproliferative disorders such as multicentric Castleman disease. Patient follow-up is based on assessing the HHV-8 viral load, which is usually achieved using real-time polymerase chain reaction (PCR). The HHV-8 Premix r-gene kit (BioMérieux) was used by some laboratories in the past, but BioMérieux ceased the production and distribution of this kit in 2021-2022. Other kits need to be tested so that they can be used for diagnostic purposes. Here we evaluated two commercial kits: HHV8 ELITe MGB Kit (ELITech) and Quanty HHV-8 (Clonit) and compared them with the HHV-8 Premix r-gene kit. MethodsWe used whole blood samples that had previously been tested with the HHV-8 Premix r-gene kit for diagnostic purposes. Overall, 46 samples (37 HHV-8-positive and 9 HHV-8-negative) were tested with the ELITe MGB Kit and 37 (29 HHV-8-positive and 8 HHV-8-negative) with the Quanty HHV-8 kit. The different methods were compared using Bland-Altman and Passing-Bablok tests with Analyse-it software. ResultsQualitative results were concordant except for one HHV-8 low-positive sample that was found to be negative by the ELITe MGB Kit. The quantitative results were also concordant; both kits showed mean differences of 0.58 log10 copies/ml and 0.73 log10 copies/ml, respectively, compared to the Premix r-gene kit. ConclusionsBoth the methods tested produced acceptable results and could be used for diagnostic purposes. It should be remembered that there is no international standard for HHV-8 quantification and that patients should always be followed using the same method.

Flower-shaped magnetic fluorescent nanoparticles based lateral flow biosensor for highly sensitive detection of cardiac troponin I

Magnetic fluorescent nanoparticles have demonstrated notable advantages as multifunctional immunoassays in lateral flow biosensor (LFB), contributing to the enhancement of both the flexibility and practicability of LFB. Herein, we synthesized flower-shaped magnetic fluorescent Nanoparticles (FMNP@QDs) with heightened fluorescence emission. The distinctive core/shell architecture of FMNP@QDs comprised the high saturation magnetization core encapsulated by oleic acid-modified Fe3O4, the flower-shaped shell made up of polymer colloids, and quantum dots (QDs) uniformly distributed on the outside. After surface modified with PEG-COOH and conjugate with cardiac troponin I (cTnI) antibodies, the FMNP@QDs were successfully applied in LFB for highly sensitive cTnI detection in samples. The limit of detection (LOD) of the proposed LFB for cTnI was 0.0097 ng/mL under fluorescent mode and 0.026 ng/mL under magnetic mode. A high level of concordance was observed between the FMNP@QDs based fluorescent LFB and the commercial CLIA method. The results indicated that the FMNP@QDs based LFB has a substantial potential for point-of-care test (POCT) technology, owing to its simple operating procedures, affordability, and enhanced sensitivity.

Environmental DNA storage and extraction method affects detectability for multiple aquatic invasive species

AbstractEnvironmental DNA (eDNA) refers to genetic material released by organisms into their surrounding environment. Collecting and identifying eDNA has gained popularity for monitoring and surveillance of aquatic invasive species. Invasive species management is most successful when an invasion is identified early while population size is likely to be low, highlighting the importance of eDNA detection sensitivity. Various factors influence DNA yield recovered from environmental samples. Environmental DNA storage and extraction methods, for example, can be adjusted to maximize DNA yield, thereby improving detectability. In this study, we compared the performance of two eDNA storage and extraction methods in detecting three common aquatic invasive species (Bythotrephes longimanus, Dreissena polymorpha, and Faxonius rusticus) across five natural ecosystems of Minnesota, United States. One method involved storing filters in 95% ethanol (EtOH) and extracting DNA using a DNeasy PowerSoil Pro Kit (Qiagen, Hilden, Germany), whereas the other method used cetyl trimethylammonium bromide (CTAB) for storage and a phenol–chloroform–isoamyl (PCI) procedure for DNA extraction. We also investigated the effect of DNA extract volume (1 μL relative to 3 μL) in qPCR reactions on eDNA detections for the commercial kit method. The CTAB‐PCI method yielded significantly more positive detections, across all three species, compared to the EtOH‐Qiagen method. Moreover, we found that using 1 μL of DNA extract in qPCR reactions was equally effective as using 3 μL. To improve detections of aquatic invasive species, we recommend that researchers store eDNA sample filters in CTAB or a similar lysis buffer such as Longmire's solution and extract with PCI when feasible, but note that lower extract volumes might be used without negative effect when either increasing technical replicates or repurposing samples for the detection of multiple species.

Synthesis of weak cation exchange/C18 bifunctional magnetic polymers for pretreatment and determination of glufosinate and its two metabolites in plasma samples

This study focuses on the purification and detection of glufosinate (GLUF) and its metabolites N-acetyl GLUF and MPP in plasma samples. A Dikma Polyamino HILIC column was used for the effective retention and separation of GLUF and its metabolites, and the innovative addition of a low concentration of ammonium fluoride solution to the mobile phase effectively improved the detection sensitivity of the target analytes. Monodisperse core-shell weak cation exchange (WCX)/C18 bifunctional magnetic polymer composites (Fe3O4@WCX/C18) were prepared in a controllable manner, and their morphology and composition were fully characterized. The Fe3O4@WCX/C18 microspheres were used as a magnetic solid-phase extraction (MSPE) adsorbent for the sample purification and detection of GLUF and its metabolites in plasma samples combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The purification conditions of Fe3O4@WCX/C18 microspheres for GLUF and its metabolites in spiked plasma samples were optimized to achieve the best MSPE efficiency. The purification mechanisms of the target analytes in plasma samples include electrostatic attraction and hydrophobic interactions. Furthermore, the effect of the molar ratio of the two functional monomers 4-VBA and 1-octadecene in the adsorbent was optimized and it shows that the bifunctional components WCX/C18 have a synergistic effect on the determination of GLUF and its metabolites in plasma samples. In addition, the present study compared the purification performance of the Fe3O4@WCX/C18 microsphere-based MSPE method with that of the commercial Oasis WCX SPE method, and the results showed that the Fe3O4@WCX/C18 microsphere-based MSPE method established in this work had a stronger ability to remove matrix interferences. Under optimal purification conditions, the recoveries of GLUF and its metabolites in plasma were 87.6–111 % with relative standard deviations (RSDs) ranging from 0.2 % to 4.8 %. The limits of detection (LODs, S/N≥3) and limits of quantification (LOQs, S/N≥10) were 0.10–0.18 μg/L and 0.30–0.54 μg/L, respectively. The MSPE-LC-MS/MS method developed in this study is fast, simple, accurate and sensitive and can be used to confirm GLUF intoxication based not only on the detection of the GLUF prototype but also on the detection of its two metabolites.

부산시 카페 상권 분석; 매장이용 카페와 테이크아웃 카페 비교

The cafe business in Busan exhibits an annual growth trend, driven by an improving economic level and an increasing demand. Trends and consumption patterns in the cafe industry are subject to various influencing factors, and the volatility has intensified, particularly due to unexpected societal changes such as COVID-19. This study aims to analyze and predict trends in Busan's cafe business by considering population trends, the number of COVID cases, and the Consumer Price Index (CPI) of Busan. In particular, according to customer usage patterns, we will classify cafes as in-store cafe and takeout cafe, and analyze trends and forecasts of the number of cafes in a multivariate time series. The data used in this paper is collected and utilized from public data, and the open source Python programming language is used for analysis. The Busan cafe commercial district analysis method uses regression analysis, SARIMAX (Seasonal AutoRegressive Integrated Moving Average with eXogenous), and VAR (Vector Autoregression). Through this, we understand how the two types of cafes are affected by environmental variables and compare the performance and prediction ability of each analysis method. The results derived from this are expected to provide useful insights into the future development direction and prediction of the local cafe commercial area.

Leaf Temperature Measurement Using Low-Resolution Thermal Camera Based on Thresholding and Clustering Techniques

Leaf temperature can indicate photosynthetic rates, leaf water status, and stomata conductance. Leaf temperature can be measured using thermal resistance sensors, thermocouple devices, infrared thermometers, or infrared thermal imaging devices. Additionally, measuring leaf temperature using a thermal camera is simple and efficient. Therefore, the research proposes a leaf temperature measurement method using AMG8833, a low-resolution (64 pixels) thermal camera. The proposed system adopts an image segmentation technique to extract the leaf area from a thermal image. The leaf temperature is then calculated by averaging the temperature values on the leaf area. The proposed system aims to utilize a low-cost and low-resolution thermal camera for measuring the leaf temperature. The proposed approach is evaluated using real images of the Dieffenbachia plant, a popular ornamental plant that can be easily planted. In the experiments, fourteen segmentation methods consisting of eight thresholding techniques and six clustering techniques are evaluated. The experimental findings on the Dieffenbachia plant indicate that the most accurate leaf temperature measurements are obtained using local thresholding with an absolute error of 0.0109 and k-means clustering with an absolute error of 0.0134. The proposed method provides a simple, effective, and low-cost leaf temperature measurement system compared to the existing systems which employ high-cost commercial thermal cameras and complex measurement methods.

Determination of Serum Biochemical Profile and Oxidant-Antioxidant Activities in Damascus Goats at Different Ages

This study aimed to research changes in biochemical profile and oxidant-antioxidant activities of Damascus goats of different ages. The 45 non-gravid Damascus goats of different ages were included in the research. They were divided into three groups of 15 goats according to age: goat kids ( - ≤ 6-months age), young goats (2-3-year age) and old goats (5-8-year age). Biochemical parameters and oxidant-antioxidant activities were determined in serum samples using commercial kits and colorimetric methods. The lowest serum urea, blood urea nitrogen, aspartate aminotransferase, total protein, albumin, globulin and magnesium levels were observed in goat kids (P < .05). Concentrations of glucose, inorganic phosphorus, non-esterified fatty acids, albumin/globulin and alanine aminotransferase decreased with age in the goats (P < .05). Serum total oxidant capacity, total antioxidants capacity and oxidative stress index levels were increased in goat kids compared to old goats (P < .05). Furthermore the highest serum glutathione and glutathione preoxidase activities were observed in young goats (P < .05). An increase was determined in concentrations of serum β-carotene and bilirubin in old goats compared to goat kids (P < .05). In contrast, serum catalase activity, arylesterase, ceruloplasmin and uric acid values did not differ between the groups. The results obtained on the biochemical profiles and oxidant-antioxidant activities of Damascus goats will contribute to monitoring this breed's age-related health and nutritional status and establishing reference values.

Aneuploidy detection in pooled polar bodies using rapid nanopore sequencing

PurposeVarious screening techniques have been developed for preimplantation genetic testing for aneuploidy (PGT-A) to reduce implantation failure and miscarriages in women undergoing in vitro fertilisation (IVF) treatment. Among these methods, the Oxford nanopore technology (ONT) has already been tested in several tissues. However, no studies have applied ONT to polar bodies, a cellular material that is less restrictively regulated for PGT-A in some countries.MethodsWe performed rapid short nanopore sequencing on pooled first and second polar bodies of 102 oocytes from women undergoing IVF treatment to screen for aneuploidy. An automated analysis pipeline was developed with the expectation of three chromatids per chromosome. The results were compared to those obtained by array-based comparative genomic hybridisation (aCGH).ResultsONT and aCGH were consistent for 96% (98/102) of sample ploidy classification. Of those samples, 36 were classified as euploid, while 62 were classified as aneuploid. The four discordant samples were assessed as euploid using aCGH but classified as aneuploid using ONT. The concordance of the ploidy classification (euploid, gain, or loss) per chromosome was 92.5% (2169 of 2346 of analysed chromosomes) using aCGH and ONT and increased to 97.7% (2113/2162) without the eight samples assessed as highly complex aneuploid using ONT.ConclusionThe automated detection of the ploidy classification per chromosome and shorter duplications or deletions depending on the sequencing depth demonstrates an advantage of the ONT method over standard, commercial aCGH methods, which do not consider the presence of three chromatids in pooled polar bodies.

The effect of United States commercial airport rate-setting methods on airport bond ratings

PurposeA major source of external funding for US airports comes from issuing municipal bonds. Credit rating agencies evaluate the bonds using multiple factors, but the judgments behind the ratings are not well understood. This paper examines if airport rate-setting methods affect the bond ratings of US airports.Design/methodology/approachUsing a set of unbalanced panel data for 58 hub airports from 2010 to 2019, we examine the effect of the rate-setting methods and other airport characteristics on Fitch’s airport bond rating.FindingsWe find that compensatory airports consistently receive a very high bond rating from Fitch. The probability of getting a very high Fitch rating increases by ∼28 percentage points for a compensatory airport. Additionally, the probability of getting a very high rating is about 33 percentage points higher for a legacy hub.Research limitations/implicationsThe study uses Fitch bond ratings. Future studies could examine if S&P’s and Moody’s ratings are also influenced by airport rate-setting methods and legacy hub status.Practical implicationsThe results uncover the linkage between bond ratings and their determinants for US airports. This information is important for investors when assessing airport creditworthiness and for airport operators as they manage capital project financing.Originality/valueThis is the first study to evaluate the effects of rate-setting methods on airport bond rating and also the first to document a statistically significant relationship between airports’ legacy hub status and bond ratings.

Comparing traditional and commercial nixtamalization of three maize landraces: impact on pozole quality and consumer acceptance

One of the most typical dishes of traditional Mexican cuisine is pozole, made with nixtamalized maize. This dish has a special place as part of the identity of Mexican culture. However, it is time-consuming to prepare. With an increasing demand for precooked maize for pozole and the limited information on its preparation process, this study aims to assess the impact of both traditional (TN) and commercial nixtamalization (CN) on the quality of processed maize and its reception by consumers, focusing on the three most popular maize landraces used in pozole recipes. This study was carried out with the Cacahuacintle (‘CAC’), Elotes Occidentales (‘EO’) and Ancho (‘AN’) landraces, which were nixtamalized using the traditional method (only lime) and the commercial method (lime + additives) and the grain was flowered. The quality of the flowered grain was determined, and a sensory analysis consisting of magnitude of difference tests, a descriptive analysis, affective test and evaluation of consumer preferences was carried out. The ‘CAC’ landrace, when processed traditionally, yielded the highest sensory and commercial quality. The ‘EO’ landrace demanded a longer flowering time, resulting in less volume but retaining the aleurone layer. This characteristic helped preserved a portion of the anthocyanins. Consistently, maize landraces subjected to traditional nixtamalization displayed higher ratings for attributes related to masa and nejayote aroma. The ‘CAC’ landrace subjected to CN faced challenges in acceptability due to odors of acetic acid and sulfuric acid. These findings underscore the importance and advantages the TN techniques. They also emphasize the need to preserve grain quality and meeting consumer preferences when exploring alternative maize processing methods for emerging markets.

Impact of Type 1 Diabetes on Renal Parameters in Children Aged One to 17 at the Mother and Child University Hospital in N'Djamena, Chad.

Background Diabetes is a metabolic disease caused by a defect in the secretion of insulin or its misuse.It is a major public health problem worldwide. While type 2 diabetes generally affects people of advanced age, type 1 diabetes generally occurs in people of younger ages and its prevalence is increasingly high among children in Chad. When it is poorly managed, it can be accompanied by several functional complicationsincluding renal failure. In order to have an overview of the incidence of this complication in children suffering from type 1 diabetesand to contribute to its better follow-up, a study was conducted at the Mother and Child University Hospital in N'Djamena whose objective was to assess the impact of type 1 diabetes on renal parameters in children aged one to 17 years. Methodology A cross-sectional study was conducted from April to June 2023 at the Mother and Child University Hospital Center in N'Djamena on 61 children with type 1 diabetes aged one to 17 years.A questionnaire sheet was submitted to the parents of the participants and the data from this sheet were analyzed while biochemical parameters were evaluated using standard commercial kit methods, the IONIX SFRI automated ion analyzer, HemoCue HbA1c501® hemoglobinometer, and spectrophotometer (BioSystems). Results Participants were ranked according to glycemic control and duration of diabetes discovery. 73.61% of the children showed alterations in renal parameters, some of which increased and others decreased; 86.9% had poor glycemic control, whichis associated with alterations in renal parameters in study participants.Multiple logistic regression showed hypercreatinemia, hyperuremia, hyperglycemia, hyperhemoglobinemia, hyperchloremia, hyponatremia, hypokalemia, hyperglycemia, hyperketonuria, hyperproteinuria, and decreased glomerular filtration rate (GFR). Conclusion It appears from this study that type 1 diabetes through glycemic control and the duration of discovery has an increasing impact on certain renal parameters and a decrease in others, leading to impaired renal function.

Mycobacterium tuberculosis complex and detection of rifampicin and isoniazid resistance, with phenotypic study and massive genome sequencing

Objective: The objective of this study is to compare the results obtained from the detection of MTBC (Mycobacterium tuberculosis Complex) and drug resistances between two commercial molecular methods, phenotypic Drug Susceptibility Testing (DST) and whole-genome sequencing. Materials and methods: Clinical samples positive for MTBC were selected. Identification and study of mutations associated with rifampicin and isoniazid resistance were carried out using 2 commercial molecular techniques and phenotypic DST, using critical concentration in liquid medium. In parallel, the analysis of Mycobacterium tuberculosis complex genome was performed by sequencing complete genomes.

Formation of the model for the commercialization of the company's digital intellectual assets

Purpose: of the study is algorithmic modeling of the commercialization of digital intellectual assets (CIAS), taking into account pricing factors, risk and the level of commercial potential, based on the identifi cation of CIAS and determination of their specifics. Methods: general scientific methods of comparative analysis, systematization and generalization, identifi cation of distinctive features and price-forming factors that take into account the specifics of the objects of research are used. To form a model of the commercialization of digital intellectual assets, the algorithmic approach, the method of expert assessments in calculating the indicator of commercial potential, approaches and methods of valuation in determining the initial value of assets were used.Results: the author formulated the defi nition of a digital intellectual asset (DIA), establishes its relationship with related categories of assets, identifi es two categories of DIA indicating common and distinctive properties. Based on the results of the identifi cation of DIA, the factors aff ecting the value and commercial potential of various types of DIA are determined. The method for calculating the indicator of the commercial potential, taking into account the factors considered, is proposed. The tools of the commercialization, as well as approaches and methods of estimating the initial cost for various categories of DIA are disclosed. The algorithmic model of the DIA commercialization is constructed. Conclusions and Relevance: the algorithmic model of commercialization of new types of assets, digital intellectual assets, proposed in the article takes into account their specifi cs and factors aff ecting the initial cost and commercial potential. The model can be used by Russian companies to increase their competitiveness in the context of the development of the digital rights and technologies market. Further research should be devoted to the specifi cation of the commercialization algorithm for certain categories of DIA: 1) intellectual property objects in digital form; 2) digital (digital utilitarian) rights to such objects and their use, implemented exclusively according to the rules of the information system (investment platform).

EFFECT OF WHITE SUGAR, BROWN SUGAR AND JAGGERY POWDER SYRUP ON BIOCHEMICAL AND HISTOPATHOLOGICAL MARKERS OF SPRAGUE-DAWLEY RATS

Hypertension accounts for 10% of the total annual health budget in developed countries.1 By 2025, the number of people living with hypertension is expected to reach 1.56 billion people.2Dietary factors that increase blood pressure (BP) are of interest to public health authorities.3,4Twenty adult male Sprague-Dawley rats were taken. All groups received standard chow ad libitum. Controls (A), received plain drinking water, and the Sucrose treatment rats received 10% sucrose solution prepared daily for 12 weeks. Non-invasive blood pressure was recorded using computer based data recording system power lab model: M-ML 856, Australia with rat tail cuff attachment.Blood samples were collected. Serum aliquots were frozen at ?80°C for: ALT, AST, TG, total cholesterol (TC), and high-density lipoprotein (HDL) were determined using commercial enzymatic methods (CELM diagnosis, São Paulo, Brazil). The concentration of VLDL and low-density lipoprotein was measured. ANOVA and Post-Hoc Tukey tests were applied to determine statistical difference among the study groups. The results showed variable effects on biochemical and histopathological findings in rat liver, kidney and pancreas. The pancreas and kidneys of the rats showed adverse inflammatory histopathological changes maximally in rats taking jaggery syrup (Shakkar) flowed by white sugar and minimal in Shakkar. The adverse effects on liver cells were maximally seen on rats given brown sugar. This study enabled us to better understand the biochemical and histopathological effects of various types of sugars available in Pakistani market in order to create awareness regarding their effects on health.

Comparison of Colistin Susceptibility Tests

Introduction: Polymyxins are important antimicrobial agents for the treatment of infections caused by Gram-negative bacteria. The susceptibility testing for polymyxins is a challenge for clinical laboratories due to the difficulty of performance, reproducibility, and accuracy of available methods. Aim: To compare the performance of the colistin susceptibility test of an automated system and a gradient test with the gold standard broth microdilution method (BMD). Materials and Methods: Multidrug-resistant isolates of Acinetobacter baumannii (n=102), Klebsiella pneumoniae (n=40), and Pseudomonas aeruginosa(n=11) were included. The VITEK 2 systems and gradient test were studied according to the manufacturer’s instructions. Broth microdilution tests were performed according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Commercial susceptibility testing methods were compared to BMD. Results: Rates of essential agreement of colistin test results between BMD, VITEK 2, and gradient test were 96.1% and 79.7%, respectively. The VITEK 2 and gradient test showed 95.4% and 94.8% of categorial agreement. The very major error rate of VITEK 2 was 3.2%, and the gradient test was 5.2%. The major error rate of VITEK 2 was 1.3%, and there was no major error for the gradient test. Conclusion and Suggestions: The very major error rate was higher in the gradient test (5.2%) than VITEK 2 (3.2%). Even if the very major error rate of VITEK 2 was lower, both resistance and susceptility results of VITEK 2 should be confirmed with the BMD test. Further studies for susceptibility testing are needed with a focus on the correlation of MIC’s results of different tests.

Denaturing and dNTPs reagents improve SARS-CoV-2 detection via single and multiplex RT-qPCR

Background The COVID-19 pandemic, caused by the SARS-CoV-2, can be effectively managed with diagnostic tools such as RT-qPCR. However, it can produce false-negative results due to viral mutations and RNA secondary structures from the target gene sequence. Methods With High Performance Computing, the complete SARS-CoV-2 genome was obtained from the GenBank/GISAID to generate consensus sequences to design primers/probes for RT-qPCR. ORF8 gene was selected, meanwhile, E and N and RNAse P were according to CDC protocol. Nasopharyngeal swab samples were collected from patients diagnosed with SARS-CoV-2. Total RNA was purified according MagMAX kit, it was used in single, and multiplex RT-qPCR. To avoid templated secondary structures, compensate nucleotide proportions and improve Ct values, a solution composed of tetraethylammonium chloride and dimethyl sulfoxide and other with corresponding to dNTPs proportions in accordance SARS-CoV-2 genome were included. Sensitivity and specificity according to Ct values were determined with the Caret package in R software. Results 126,576 SARS-CoV-2 genomes from January to December 2020 comprised a database. From this, a region near of 5′ ORF8 gene showed three stem-loops was used for primers/FAM-probe. 49 samples were obtained, from them, 22 were positive to gene selected regions. Interestingly, samples from October to November 2020 were positive for all regions, however, in January 2021 different results were observed in ORF8. An improvement in Ct with the adjuvant solutions was determined in all samples with others SARS-CoV-2 primers/probes, for both single and multiplex RT-qPCR. The inclusion of the denaturing solution in single RT-qPCR increased its sensitivity with respect to the commercial method, while in multiplex the opposite was generated. Conclusions Including adjuvant solutions to prevent the formation of RNA secondary structures and the adjustment of the nucleotide ratios of SARS-CoV-2 improved single and multiplex RT-qPCR for viral identification, demonstrating its potential application in health public.

Overview of Modern Commercial Kits for Laboratory Diagnosis of African Swine Fever and Swine Influenza A Viruses.

Rapid and early detection of infectious diseases in pigs is important, especially for the implementation of control measures in suspected cases of African swine fever (ASF), as an effective and safe vaccine is not yet available in most of the affected countries. Additionally, analysis for swine influenza is of significance due to its high morbidity rate (up to 100%) despite a lower mortality rate compared to ASF. The wide distribution of swine influenza A virus (SwIAV) across various countries, the emergence of constantly new recombinant strains, and the danger of human infection underscore the need for rapid and accurate diagnosis. Several diagnostic approaches and commercial methods should be applied depending on the scenario, type of sample and the objective of the studies being implemented. At the early diagnosis of an outbreak, virus genome detection using a variety of PCR assays proves to be the most sensitive and specific technique. As the disease evolves, serology gains diagnostic value, as specific antibodies appear later in the course of the disease (after 7-10 days post-infection (DPI) for ASF and between 10-21 DPI for SwIAV). The ongoing development of commercial kits with enhanced sensitivity and specificity is evident. This review aims to analyse recent advances and current commercial kits utilised for the diagnosis of ASF and SwIAV.