Bacterial biosensors have great potential in contaminant detection for sensitivity, specificity, cost-effectiveness, and easy operation. However, the existing cadmium-responsive bacterial biosensors cannot meet the real-world detection requirements due to lack of sensitivity, specificity, and anti-interference capability. This study aimed to develop a bacterial biosensor for detecting the total and extractable cadmium in actual environmental samples. We constructed the cadmium-responsive biosensor with the regulatory element (cadmium resistance transcriptional regulatory, CadR) and the reporting element (GFP) and improved its performance by directed evolution. The mutant libraries of biosensors were generated by error-prone PCR and screened by continuous five-round fluorescence-activated cell sorting (FACS), and a bacteria variant epCadR5 with higher performance was finally isolated. Biosensor fluorescence intensity was measured by a microplate reader, and results showed that the evolved cadmium-responsive bacterial biosensor was of high sensitivity and specificity in detecting trace cadmium, with a detection limit of 0.45 μg/L, which is 6.8 times more specific to cadmium than that of the wild-type. Furthermore, microscopic qualitative analysis results showed that the bacteria could produce fluorescence response in a cadmium-contaminated soil matrix, and quantitative analysis results showed that the values of cadmium from epCadR5 bacteria were close to that from inductively coupled plasma-mass spectrometry. These results suggest that the biosensor may have a broad application prospect in the detection of cadmium-contaminated soil and water.
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http://dx.doi.org/10.1021/acs.est.2c00627 | DOI Listing |
Acta Radiol
January 2025
Department of Radiology, Changi General Hospital, Singapore, Republic of Singapore.
Background: Computed tomography (CT) is the gold standard imaging modality for the assessment of 3D bony morphology but incurs the cost of ionizing radiation exposure. High-resolution 3D magnetic resonance imaging (MRI) with CT-like bone contrast (CLBC) may provide an alternative to CT in allowing complete evaluation of both bony and soft tissue structures with a single MRI examination.
Purpose: To review the technical aspects of an optimized stack-of-stars 3D gradient recalled echo pulse sequence method (3D-Bone) in generating 3D MR images with CLBC, and to present a pictorial review of the utility of 3D-Bone in the clinical assessment of common musculoskeletal conditions.
Afr J Prim Health Care Fam Med
December 2024
Department of Internal Medicine, Prince Mshiyeni Memorial Hospital, Durban.
Background: Tuberculosis (TB) remains a leading cause of mortality in low-resource settings and poses a diagnostic challenge in human immunodeficiency virus (HIV)-negative populations because of limitations in traditional diagnostic methods such as sputum smear microscopy (SSM) and sputum Xpert Ultra. There is a lack of effective, non-invasive diagnostic options for TB diagnosis in HIV-negative populations. This scoping review explores the potential of urinary lipoarabinomannan (ULAM) as a point-of-care diagnostic tool for Mycobacterium tuberculosis (MTB) in HIV-negative individuals.
View Article and Find Full Text PDFHealth Sci Rep
January 2025
Department of Research The Medical Research Circle (MedReC) Goma Democratic Republic of the Congo.
Background And Aim: Epilepsy is a major neurological challenge, especially for pediatric populations. It profoundly impacts both developmental progress and quality of life in affected children. With the advent of artificial intelligence (AI), there's a growing interest in leveraging its capabilities to improve the diagnosis and management of pediatric epilepsy.
View Article and Find Full Text PDFFront Immunol
January 2025
Division of Infectious Diseases, Department of Internal Medicine, State Key Laboratory of Complex Severe and Rare Disease, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Objective: This study aims to evaluate the diagnostic accuracy of a (MTB)-specific triple-color FluoroSpot assay (IFN-γ/IL-2/TNF-α) in the differentiation of tuberculosis (TB) infection status in febrile patients.
Method: Febrile patients with suspected active TB (ATB) were consecutively enrolled. The frequencies and proportions of MTB-specific T cells secreting IFN-γ, IL-2, and TNF-α were detected at the single-cell level by triple-color FluoroSpot assay.
Front Immunol
January 2025
Center for Translational Science, Florida International University, Port Saint Lucie, FL, United States.
Sepsis is a severe and life-threatening medical syndrome that can lead to organ failure and death. Despite advances in medical treatment, current therapies are often inadequate, with high septic mortality rates. Therefore, there is a critical need for reliable prognostic markers to be used in clinical settings to improve the management and outcomes of patients with sepsis.
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