Nitrate Reductase Assay for Rapid Determination of Methicillin-Resistant Staphylococcus aureus Clinical Isolates.

OBJECTIVE: To evaluate the performance of nitrate reductase assay (NRA), a rapid, colorimetric method for the determination of methicillin resistance in Staphylococcus aureus isolates obtained from the culture collection of the Akdeniz University Hospital Central Laboratory, Antalya, Türkiye. MATERIALS AND METHODS: Identification for all 290 S aureus isolates at the species level was performed via matrix-assisted laser desorption/ionization-time of flight. Isolates were tested with NRA for methicillin resistance. The cefoxitin broth microdilution (BMD) method recommended by the Clinical and Laboratory Standards Institute was used as the reference method in the study. S aureus ATCC 29213 and S aureus ATCC 43300 strains were used for quality control. RESULTS: According to Food and Drug Administration criteria, the category agreement between NRA and BMD was found to be 100%. The essential agreement between both methods was determined to be 96.20%. There is no minor, major, or extremely major discrepancy between both methods. CONCLUSION: The results show that NRA is a rapid, practical, and reliable colorimetric method for detecting MRSA.

Analysis of the Relationship between Physical Activity and the Factors Related to Weight Management of Bariatric Surgery Patients.

Background: We aimed to analyze the relationship between physical activity and the factors related to the weight management of bariatric surgery patients. Methods: This descriptive-correlational study was conducted on 87 participants, who underwent bariatric surgery in Cyprus between May and Oct 2020. The International Physical Activity Questionnaire and a questionnaire on socio-demographic and obesity characteristics were used to collect data. Results: Mean age of the participants was 34.7±8.43 and 65.5% were female. A statistically significant difference was found between physical activity levels and weight loss (P=0.021). Post-bariatric surgery physical activity level was low active for 65.5% of the participants. There was a statistically significant difference between the MET scores of the participants according to their gender, and the scores of men were higher than women (2256.9; 1110.9 respectively). Although most of the participants in the study were females, women lost less weight than males (45.5; 54.2 respectively). Conclusion: Being female, married, and having chronic diseases caused less weight loss after bariatric surgery. As the physical activity levels of the patients increased, their weight loss increased. In line with these results, people undergone bariatric surgery and are at risk of regaining weight should be followed closely after surgery and appropriate physical activities should be planned.

Resazurin microplate test method for rapid determination of colistin resistance in carbapenem-resistant Acinetobacter baumanii isolates.

BACKGROUND: Colistin-resistant Acinetobacter baumannii isolates are extremely important pathogens for hospital-acquired infections. OBJECTIVE: To investigate the effectiveness of the resazurin microplate assay (REMA) for the rapid determination of colistin resistance. METHODS: Susceptibility for colistin was investigated in vitro by the broth microdilution method (BMD) and the resazurin microplate assay (REMA) on 106 carbapenem-resistant Acinetobacter baumannii isolates. RESULTS: The results of both test methods were compared, and the categorical agreement between them was found to be 100%. No minor, major, or very major discrepancy was observed between the 2 methods. CONCLUSIONS: The most important advantages of REMA are that the results are obtained within 6 hours compared to the reference method, that it is easy to evaluate because it is colorimetric, and that the susceptibility result can be reported to the clinician on the same day as bacterial identification.

Superior Vena Cava Flow in Children With Attention Deficit Hyperactivity Disorder.

OBJECTIVE: Attention deficit/hyperactivity disorder (ADHD), whose definition, diagnosis and treatment has been the subject of debate in the scientific community for a long time, is the most common neurobehavioral disorder in childhood. There are many studies on the pathophysiology of attention deficit. However, there is no study in the literature based on direct or indirect measurement of cerebral venous circulation in ADHD, and the effect of methylphenidate (MPH) treatment on cerebral venous circulation. Therefore, it was aimed to noninvasively measure superior vena cava (SVC) flow, which is an indirect indicator of cerebral venous flow, by transthoracic echocardiography in patients with ADHD. METHODS: In the study, 44 healthy children, and 40 ADHD patients who were planned to start on osmotic-release oral system (OROS)- MPH were included. SVC flows were measured in healthy children and before and after drug therapy of ADHD patients. RESULTS: SVC flow was found to be higher in ADHD patients compared to healthy children. A significant decrease was found in SVC flow of ADHD patients after OROS-MPH treatment. There was no decrease in SVC flow of patients who did not respond adequately to MPH treatment. CONCLUSION: This first study of SVC flow in children with ADHD showed that ADHD was associated with increased SVC flow and MPH treatment had a reducing effect on this increased SVC flow. We believe that noninvasive, easily measurable, and reproducible SVC flow may be a new focus of interest for future comprehensive studies as a biomarker to support clinical evaluation in the diagnosis and treatment follow-up of ADHD patients.

Evaluation of glutaraldehyde coagulation test and colostrum BRIX refractometer compared with SNAP foal IgG test in neonatal foals.

BACKGROUND: Prompt diagnosis of passive transfer failure in the neonatal period is important for early treatment. OBJECTIVES: To compare the diagnostic performance of serum glutaraldehyde coagulation test (GCT) and colostrum BRIX% for failure to transfer passive immunity (FTPI) diagnosis with the results of SNAP foal test and to evaluate the results of serum GCT and colostrum BRIX% measurements in foals with diarrhoea in the 0-1 month period. STUDY DESIGN: In vitro experiments. METHODS: Excess serum and colostrum (n: 298) from samples collected from newborn foals and their dams for clinical purposes were used. Foals were classified as FTPI positive (IgG < 8 g/L) or negative (IgG ≥ 8 g/L) using the SNAP foal test. We compared the sensitivity and specificity of serum GCT and colostrum BRIX % for diagnosing FTPI in all foals and in the sub-group of foals which developed diarrhoea within the first month of life was noted. The relationships between the results of the serum GCT and colostrum BRIX% and diarrhoea in foals with and without FTPI were evaluated. RESULTS: Serum GCT and colostrum BRIX % were statistically significantly different (p < 0.05) between the foals without FTPI and with FTPI classified according to the SNAP test. Using a cut-off value for serum GCT of >10, sensitivity was 100% (95% CI 92.9%-100%) and specificity 100% (98.3%-100%) while with a cut-off value of ≤24, with colostrum BRIX% of ≤24 sensitivity was 92% (80.9%-97.8%), and specificity was 98% (95.3-99.3). In the sub-group of foals without FTPI using a colostrum BRIX% cut-off value of ≤26 the sensitivity for prediction of diarrhoea in the 0-1 month period was only 72.4% (52.8-87.3, p < 0.001) with specificity 54.3% (47.6-61.1) but the test performance was not robust (ROC AUC 0.61). MAIN LIMITATIONS: The number of repeated measurements in the evaluation of serum GCT, and colostrum BRIX% was low. More clinical problems could be examined. CONCLUSIONS: The serum GCT, and colostrum BRIX%, both economical and practical to use in the field, gave results comparable with the SNAP foal IgG test. The ability to accurately predict diarrhoea in the first month of life with these tests was limited.

INTRODUCTION/CONTEXTE: Être capable de diagnostiquer rapidement un défaut de transfert d'immunité passive en période néonatale est primordial au prompt traitement des poulains. OBJECTIFS: Comparer la performance diagnostique du test de coagulation au glutaraldéhyde sur sérum (GCT) et du BRIX du colostrum pour le diagnostic de défaut de transfert d'immunité passive (FTPI) avec les résultats de test SNAP Foal. Évaluer les résultats de GCT sur sérum et les mesures de colostrum BRIX chez les poulains âgés de 0-1 mois d'âge souffrant de diarrhée. TYPE D'ÉTUDE: Étude in vitro. MÉTHODES: Les excédents de sérum et colostrum (N = 298) provenant de poulains nouveaux-nés et leur mère à partir d'échantillons cliniques ont été sauvegardés. Les poulains ont été divisés en deux groupes: FTPI négatifs (IgG ≥ 8 g/L) et positifs (IgG ≤ 8 g/L). La spécificité et la sensibilité de GCT sur sérum et le % BRIX du colostrum ont été comparés pour diagnostiquer les défauts de transfert d'immunité passive chez tous les poulains, incluant le sous-groupe ayant développé de la diarrhée. En parallèle, le développement de diarrhée chez les poulains jusqu'à 1 mois d'âge a été noté. La relation entre les résultats de GCT sur sérum et le % BRIX du colostrum et la diarrhée chez les poulains souffrant de diarrhée avec ou sans défaut de transfert d'immunité passive a été évaluée. RÉSULTATS: Le GCT sur sérum et le % BRIX du colostrum ont montré une différence statistiquement significative (p < 0.05) entre les poulains sans FTPI et ceux avec FTPI tel que déterminé par le SNAP Foal test. En utilisant une valeur seuil pour le GCT sur sérum de >10, la sensibilité était de 100% (95% IC 92.9%-100%) et la spécificité de 100% également (98.3%-100%). Avec une valeur seuil à ≤24, avec une valeur au colostrum BRIX% de ≤24, la sensibilité était de 92% (80.9%-97.8%) et la spécificité de 98% (95.3%-99.3%). Dans le groupe de poulains sans défaut de transfert d'immunité passive, en utilisant une valeur seuil de ≤26, la sensibilité pour la détection de diarrhée durant la période de 0-1 mois d'âge était seulement de 72.4% (52.8-87.3%, p < 0.001) avec une spécificité de 54.3% (47.6%-61.1%), mais la performance du teste n'était considérée robuste (ROC AUC 0.61). LIMITES PRINCIPALES: Le nombre de mesures répétées lors de l'évaluation de GCT sur sérum et du % BRIX de colostrum était bas. Davantage de paramètres pourraient être ajoutés. CONCLUSIONS: Le GCT sur sérum et le % BRIX de colostrum, tous deux économique et facile à utiliser en pratique, ont donné des résultats comparables aux résultats de SNAP Foal pour les immunoglobulines G.

Automated Urine Cell Image Classification Model Using Chaotic Mixer Deep Feature Extraction.

Microscopic examination of urinary sediments is a common laboratory procedure. Automated image-based classification of urinary sediments can reduce analysis time and costs. Inspired by cryptographic mixing protocols and computer vision, we developed an image classification model that combines a novel Arnold Cat Map (ACM)- and fixed-size patch-based mixer algorithm with transfer learning for deep feature extraction. Our study dataset comprised 6,687 urinary sediment images belonging to seven classes: Cast, Crystal, Epithelia, Epithelial nuclei, Erythrocyte, Leukocyte, and Mycete. The developed model consists of four layers: (1) an ACM-based mixer to generate mixed images from resized 224 × 224 input images using fixed-size 16 × 16 patches; (2) DenseNet201 pre-trained on ImageNet1K to extract 1,920 features from each raw input image, and its six corresponding mixed images were concatenated to form a final feature vector of length 13,440; (3) iterative neighborhood component analysis to select the most discriminative feature vector of optimal length 342, determined using a k-nearest neighbor (kNN)-based loss function calculator; and (4) shallow kNN-based classification with ten-fold cross-validation. Our model achieved 98.52% overall accuracy for seven-class classification, outperforming published models for urinary cell and sediment analysis. We demonstrated the feasibility and accuracy of deep feature engineering using an ACM-based mixer algorithm for image preprocessing combined with pre-trained DenseNet201 for feature extraction. The classification model was both demonstrably accurate and computationally lightweight, making it ready for implementation in real-world image-based urine sediment analysis applications.

The Effect of Inoculum Size on Antimicrobial Susceptibility Testing of Mycobacterium tuberculosis.

Phenotypic drug susceptibility testing (DST) requires a standardized amount of inoculum to produce reproducible susceptibility results. The most critical step in the application of DST in Mycobacterium tuberculosis isolates is the preparation of the bacterial inoculum. In this study, the effect of bacterial inoculum prepared in various McFarland turbidities on primary antituberculosis drug susceptibility of M. tuberculosis strains was investigated. Five standard ATCC strains (ATCC 27294 [H37Rv], ATCC 35822 [izoniazid-resistant], ATCC 35838 [rifampicin-resistant], ATCC 35820 [streptomycin-resistant], ATCC 35837 [ethambutol-resistant]) were tested. Inoculums of McFarland standard of 0.5, 1, 2, 3, and 1:100 dilutions of 1 McFarland standard of each strain were used. The effect of inoculum size on DST results was determined by the proportion method in Lowenstein-Jensen (LJ) medium and nitrate reductase assay (NRA) in the LJ medium. In both test methods, the increase in inoculum size did not affect the DST results of the strains. On the contrary, DST results were obtained more rapidly as a result of the use of dense inoculum. DST results obtained in all McFarland turbidities were found to be 100% compatible with the recommended amount of inoculum, 1:100 dilution of 1 McFarland standard (inoculum size of gold standard method). In conclusion, the use of a high amount of inoculum did not change the drug susceptibility profile of tuberculosis bacilli. Minimizing manipulations during the inoculum preparation phase of susceptibility testing, this outcome will decrease the need for equipment and make the test application easier, particularly in developing countries. IMPORTANCE During DST application, it can be challenging to evenly homogenize TB cell clumps with lipid-rich cell walls. These experiments must be carried out under Biosafety Level-3 (BSL-3) laboratory conditions with personal protective equipment and taking safety precautions because the procedures applied at this stage cause the formation of bacillus-laden aerosols and carry a serious risk of transmission. Considering this situation, this stage is important given that it is not possible to establish a BSL-3 laboratory in poor and developing countries. Reducing the manipulations to be applied during the preparation of bacterial turbidity will minimize the risk of aerosol formation. Perhaps there will be no need to do these steps for susceptibility tests in these countries or even in developed countries.

Comparative assessment of treatment efficacy and adverse effects during nonextraction orthodontic treatment of Class I malocclusion patients with direct and indirect bonding: A parallel randomized clinical trial.

INTRODUCTION: The objective of this 2-arm parallel trial was to compare the effects of direct and indirect bonding techniques on the orthodontic treatment process and outcomes. METHODS: Thirty patients were randomly assigned to undergo bonding of brackets indirectly (group A, n = 15) or directly (group B, n = 15). Eligibility criteria included permanent dentition with bilateral Angle Class I molar and canine relationships, no previous orthodontic treatment, no skeletal discrepancy, and mild or moderate crowding. The main outcome was the orthodontic treatment results assessed using the American Board of Orthodontics Objective Grading System; the secondary outcomes were times taken to perform the laboratory and clinical steps, total treatment duration, plaque accumulation, formation of white spot lesions, bond failures, and need for additional archwire bending and bracket repositioning. The randomization sequence was created using an online randomization software. The patients were allocated with a 1:1 ratio using a block size of 4. The sequence generator was contacted by phone for group assignment after a patient was enrolled for allocation concealment. Blinding was implemented during the dental cast and radiographic evaluations, data entry, and data analysis. Patients were evaluated before treatment, and 1, 2, and 6 months after the start of treatment, and at the end of treatment. RESULTS: All patients completed the study and were analyzed. There were no dropouts. Marginal ridge (median difference, -1.000; 95% confidence interval [CI], -2.99 to -0.001; P = 0.03) and total Objective Grading System scores (median difference, -3.999; 95% CI, -6.000 to -0.005; P = 0.03) were significantly higher in group B than in group A; other Objective Grading System categories did not differ significantly between the groups. The clinical time was significantly longer in group B than in group A (mean difference, -26.51; 95% CI, -29.57 to -23.46; P <0.001), and the total time was significantly longer in group A than in group B (mean difference, 19.03; 95% CI, 15.32 to 22.74; P <0.001). There were no significant between-group differences in treatment duration, plaque accumulation, formation of white spot lesions, bond failure, or need for additional archwire bending or bracket repositioning. No harms were encountered. CONCLUSIONS: Indirect bonding was significantly faster than direct bonding in the clinical stage and yielded better marginal ridge and total scores. Both techniques showed similar rates of plaque accumulation, formation of white spot lesions, bond failure, and additional archwire bending and bracket repositioning. REGISTRATION: The trial was not registered. PROTOCOL: The protocol was not published before trial commencement.

Leptin induces ADAMTS-4, ADAMTS-5, and ADAMTS-9 genes expression by mitogen-activated protein kinases and NF-ĸB signaling pathways in human chondrocytes.

Elucidation of the causes of inflammation has vital importance in the development of new approaches for the treatment of arthritic diseases. The degradation of aggrecan by upregulated disintegrin and metalloproteinase with trombospondin motifs (ADAMTSs) is the key event in the development of both rheumatoid arthritis (RA) and osteoarthritis (OA). Increased levels of leptin in both RA and OA have been demonstrated, thus linking leptin to arthritic diseases, but the mechanism has not been clarified. This study investigated the putative role of signaling pathways (p38, JNK, MEK1, NF-ĸB, and PI3) involved in leptin-induced cartilage destruction. Normal human articular chondrocytes were cultured with recombinant human leptin at 100, 250, 500, and 1000 ng/mL doses for 6, 12, 24, and 48 h, after which ADAMTS-4, -5, and -9 genes expression were determined by real time-polymerase chain reaction (RT-PCR) and Western Blot methods. The signaling pathways involved in leptin-induced ADAMTSs upregulation were also investigated by using inhibitors of signaling pathways. It was demonstrated that ADAMTSs expression level was peaked at 1000 ng/mL doses for 48 hours, and MAPKs (p38, JNK, and MEK) and NF-ĸB signaling pathways involving in leptin triggered ADAMTSs upregulation. Obesity as a risk for RA and OA may contribute to the inflammation of both RA and OA diseases by secreting adipokines like leptin. We hypothesize that leptin is involved in the development of RA and OA accompanied with obesity by increasing ADAMTS-4, -5, and -9 genes expression via MAPKs and NF-ĸB signaling pathways.