The influence of various conditions of freezing in liquid nitrogen on the motility, virulence, antigens, and immunogenicity of Treponema pallidum was studied. The suspending medium, rate of freezing, kind and concentration of cryprotector, and duration of preincubation with cryoprotector were found to be critical. On the basis of the results obtained the optimal conditions of freezing of T. pallidum in liquid nitrogen were established. These are: the Nelson-Diesendruck medium with the addition of 10% DMSO; freezing rate 1 degree per min, and thawing rate between 12.6 degrees and 120 degrees per min.
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Rev Argent Microbiol
January 2025
Instituto De Química Biológica de la Facultad de Ciencias Exactas y Naturales-CONICET, Buenos Aires, Argentina; Departamento de Química Biológica, FCEyN-UBA, Buenos Aires, Argentina. Electronic address:
DNA extraction is crucial for conducting procedures, such as whole-genome sequencing, which demand methods that are reproducible and cost-effective. Lysing Staphylococcus aureus cells is particularly challenging due to their peptidoglycan layer that is resistant to common treatments. Traditional methods involve costly enzymatic lysis using lysostaphin.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006 China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, School of Advanced Manufacturing, Guangdong University of Technology, Jieyang 515200 China. Electronic address:
Extrusion-based printing of macroscopic architectures layer-by-layer offers new opportunities for constructing customized electromagnetic interference (EMI) shielding materials. However, current research primarily focuses on improving the printability of material inks by increasing contents and adding various modifiers, controllable construction of ultralight and robust macro-architectures with structural design at both macro- and micro-scales is still challenging. Herein, we develop a graphene oxide foaming ink enriched with air bubbles for direct-ink writing, enabling the creation of macroscopic graphene architectures with arbitrary geometries.
View Article and Find Full Text PDFMicrobiol Spectr
January 2025
College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.
The rumen microbiota plays a vital role in the nutrient metabolism affecting the growth of velvet antler. However, the fermentation patterns and dynamics of the rumen microbiota across growth stages of velvet antler remain largely unexplored. Here, we employed an fermentation approach to assess fermentation parameters and microbial composition in the rumen liquid of sika deer during the early growth (EG), metaphase growth (MG), and fast growth (FG) phases .
View Article and Find Full Text PDFSci Rep
January 2025
Chemistry Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt.
Three composites based on Poly (meta-aminophenol) (PmAP), (3-aminopropyl) triethoxysilane (APTES) and graphene oxide (GO) were synthesized with initial GO dispersion of 3.3, 6.6, and 9.
View Article and Find Full Text PDFCryobiology
January 2025
ICAR-National Bureau of Plant Genetic Resources, New Delhi-110 012 INDIA.
Ex situ conservation of plant genetic resources (PGR) plays a crucial role in sustainable growth and development, as highlighted by the Global Strategy for Plant Conservation (GSPC). Seed genebanks, a key component of ex situ conservation, have been instrumental in preserving plant diversity. However, challenges arise with the conservation of non-orthodox (recalcitrant and intermediate) seeds and vegetative tissues, which are not amenable to storage in traditional genebanks at temperatures of -20°C.
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