A direct, sensitive, near-real-time, handheld optical immunoassay device was developed to detect Salmonella typhimurium in the naturally occurring liquid from fresh poultry packages (hereafter "chicken matrix"), with just single pipetting of sample (i.e., no filtration, culturing and/or isolation, thus reducing the assay time and the error associated with them). Carboxylated, polystyrene microparticles were covalently conjugated with anti-Salmonella, and the immunoagglutination due to the presence of Salmonella was detected by reading the Mie scatter signals from the microfluidic channels using a handheld device. The presence of chicken matrix did not affect the light scatter signal, since the optical parameters (particle size d, wavelength of incident light λ and scatter angle θ) were optimized to minimize the effect of sample matrix (animal tissues and blood proteins, etc.). The sample was loaded into a microfluidic chip that was split into two channels, one pre-loaded with vacuum-dried, antibody-conjugated particles and the other with vacuum-dried, bovine serum albumin-conjugated particles. This eliminated the need for a separate negative control, effectively minimizing chip-to-chip and sample-to-sample variations. Particles and the sample were diffused in-channel through chemical agitation by Tween 80, also vacuum-dried within the microchannels. Sequential mixing of the sample to the reagents under a strict laminar flow condition synergistically improved the reproducibility and linearity of the assay. In addition, dried particles were shown to successfully detect lower Salmonella concentrations for up to 8 weeks. The handheld device contains simplified circuitry eliminating unnecessary adjustment stages, providing a stable signal, thus maximizing sensitivity. Total assay time was 10 min, and the detection limit 10 CFU mL(-1) was observed in all matrices, demonstrating the suitability of this device for field assays.
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http://dx.doi.org/10.1016/j.bios.2012.07.076 | DOI Listing |
Radiol Med
January 2025
Department of Radiology, University Hospital, LMU Munich, Marchioninistr. 15, 81377, Munich, Germany.
Purpose: To develop an artificial intelligence (AI) algorithm for automated measurements of spinopelvic parameters on lateral radiographs and compare its performance to multiple experienced radiologists and surgeons.
Methods: On lateral full-spine radiographs of 295 consecutive patients, a two-staged region-based convolutional neural network (R-CNN) was trained to detect anatomical landmarks and calculate thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), and sagittal vertical axis (SVA). Performance was evaluated on 65 radiographs not used for training, which were measured independently by 6 readers (3 radiologists, 3 surgeons), and the median per measurement was set as the reference standard.
Plant Cell Rep
January 2025
MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou, 510631, China.
The three SDEs of CLas were expressed in citrus leaves by AuNPs-PEI mediated transient expression system, and promoted the proliferation of CLas and inhibited citrus immunity. Huanglongbing (HLB) is the most severe bacterial disease of citrus caused by Candidatus Liberibacter asiaticus (CLas). CLas suppress host immune responses and promote infection by sec-dependent effectors (SDEs), thus insight into HLB pathogenesis is urgently needed to develop effective management strategies.
View Article and Find Full Text PDFEJNMMI Phys
January 2025
Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Solna, Sweden.
Background: System calibration is essential for accurate SPECT/CT dosimetry. However, count losses due to dead time and pulse pileup may cause calibration errors, in particular for I, where high count rates may be encountered. Calibration at low count rates should also be avoided to minimise detrimental effects from e.
View Article and Find Full Text PDFCytotherapy
January 2025
Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain. Electronic address:
Background/aims: Human mesenchymal stromal cells (hMSC) are multipotent adult cells commonly used in regenerative medicine as advanced therapy medicinal products. The expansion of these cells in xeno-free supplements is highly encouraged by regulatory agencies due to safety concerns. However, the number of supplements with robust performance and consistency for hMSC expansion are limited.
View Article and Find Full Text PDFJ Adolesc Health
January 2025
The National Alliance to Advance Adolescent Health/Got Transition, Washington, D.C.
Purpose: There is a paucity of evidence examining clinician experiences with structured health-care transition (HCT) programs. Among HCT Learning Collaborative participants, this study describes clinician experiences with implementation of a structured HCT process: Got Transition's 6 Core Elements.
Methods: Representative members from 6 health systems designed a survey to collect clinician feedback regarding HCT and demographic and practice information.
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