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Enterobacterales carrying bla NDM represent an emerging challenge in treating infectious diseases. In this study, we aimed to investigate the characteristics of bla NDM -producing Enterobacterales from three hospitals in southern Taiwan. Enterobacterales strains that were nonsusceptible to more than one carbapenem (ertapenem, meropenem, imipenem, or doripenem) were collected from hospitalized patients. Molecular typing for New Delhi metallo-β-lactamase (NDM) and antibiotic susceptibility tests were performed, followed by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and plasmid analysis by PCR-based replicon typing. A total of 1311 carbapenem-nonsusceptible Enterobacterales were isolated from 2017 to 2021. bla NDM -encoding genes were detected in 108 isolates, with 53 (49.1%) harboring bla NDM-1 and 55 (50.9%) harboring bla NDM-5. The rate of bla NDM-1 detection among isolates decreased to 2% in 2021. However, the rate of E. coli harboring bla NDM-5 increased from 1% to 12% of total isolates during the study period. Of 47 NDM-5-positive E. coli isolates, 44 (93.6%) were ST8346 with high genetic relatedness. E. coli ST8346 isolates showed high-level resistance to both carbapenems and aminoglycosides. Most (38 out of 47, 80.9%) bla NDM-5 -harboring E. coli isolates co-harbored bla OXA-181. We analyzed the regions harboring bla NDM-5 in E. coli ST8346 via PCR amplification. bla NDM-5 and bla OXA-181 were located on two separate plasmids, IncF and IncX3, respectively. The dissemination of E. coli ST8346 caused an increase in bla NDM-5 and bla OXA-181 co-harboring Enterobacterales in southern Taiwan, which show high-level resistance to both carbapenems and aminoglycosides. We identified a distinct IncF plasmid encoding bla NDM-5 that has the potential for rapid spread and needs further surveillance. [ABSTRACT FROM AUTHOR]

Glucocorticoid-induced osteoporosis (GIOP) changes the microarchitecture of bones and often leads to the reduction of bone-mineral density (BMD) and increased fracture rates. Zebrafish has been used as an alternative model for GIOP, however, the interaction of GIOP, and its treatment, with zebrafish bone morphometrics and mechanical properties, remains a challenge. Thus, this study aimed to evaluate the effects of prednisolone and alendronate on the properties of zebrafish vertebrae. Adult 7-month-old zebrafish were distributed into four groups: control (CTRL), prednisolone-only (PN), alendronate-only (ALN), and the sequential use of both medicines (PN + ALN). Fish skeletons were scanned via micro-tomography (n = 3) to obtain vertebra morphometrics (e.g., BMD). Bone morphology was assessed using scanning electron microscopy (n = 4) and the biomechanical behaviour with nanoindentation technique (n = 3). The BMD decreased in PN (426.08 ± 18.58 mg/cm3) and ALN (398.23 ± 10.20 mg/cm3) groups compared to the CTRL (490.43 ± 41.96 mg/cm3) (p < 0.001); however, administering the medicines in sequence recovered the values to healthy levels (495.43 ± 22.06 mg/cm3) (p > 0.05). The bone layered structures remain preserved in all groups. The vertebrae of the groups that received ALN and PN + ALN, displayed higher modulus of elasticity (27.27 ± 1.59 GPa and 25.68 ± 2.07 GPa, respectively) than the CTRL (22.74 ± 1.60 GP) (p < 0.001). ALN alone increased the hardness of zebrafish vertebrae to the highest value among the treatments (1.32 ± 0.13 GPa) (p < 0.001). Conversely, PN + ALN (1.25 ± 0.11 GPa) showed unaltered hardness from the CTRL (1.18 ± 0.13 GPa), but significantly higher than the PN group (1.08 ± 0.12 GPa) (p < 0.001). ALN administered after GIOP development, rescued osteoporotic condition by recovering the BMD and bone hardness in zebrafish vertebrae. [Display omitted] • The intake of prednisolone-only decreased the BMD of zebrafish vertebrae. • Neither prednisolone nor alendronate altered the morphology of zebrafish backbone. • Bone hardness was not affected by the sequential use of medicines. • Osteoporosis showed no influence on zebrafish vertebrae elastic modulus. • Prednisolone followed by alendronate intake rescued osteoporosis phenotype. [ABSTRACT FROM AUTHOR]

Be it animals or plants, most of the organism's offspring come into existence after their embryos develop inside a protective shell. In plants, these hard protective shells are called endocarps. They serve the function of nourishing and protecting the seeds from external mechanical damage. Through evolution, endocarps of plants have developed various structural strategies to protect the enclosed seeds from external threats, and these strategies can vary according to the habitat or lifestyle of a particular plant. One such intriguing hard plant shell is the endocarp of the Elaeocarpus ganitrus fruit. It mostly grows in South Asia's mountainous forests, and its endocarps are known in the local communities as unbreakable and everlasting prayer beads. We report an in-depth investigation on microstructure, tomography, and mechanical properties to cast light on its performance and the underlying structure-property relation. The 3D structural quantifications by micro-CT demonstrate that the endocarp has gradient microarchitecture. In addition, the endocarp also exhibits gradient hardness and stiffness. The toughening mechanisms arising from the layered cellular structure enable the endocarps to withstand higher loads up to 5000 N before they fracture. Our findings provide experimental evidence of outstanding fracture tolerance and seed protection strategies developed by Elaeocarpus ganitrus endocarp that encourage the design of synthetic fracture tolerant structures. Endocarps are low-density plant shells that exhibit remarkable fracture resistance and energy absorption when they encounter impact by falling from high trees and prolonged compression and abrasion by the predators. Such outstanding mechanical performance originates through structural design strategies developed to protect their seeds. Here we demonstrate previously undiscovered structural features and mechanical properties of Elaeocarpus ganitrus endocarp. We scrutinize the microstructure using high-resolution x-ray tomography scans and the 3D structural quantifications reveal a gradient microstructure which is in agreement with the gradient hardness and stiffness. The multiscale hierarchical structures combined with the gradient motif yield impressive fracture tolerance in Elaeocarpus ganitrus endocarp. These findings advance the knowledge of the structure-property relation in hard plant shells, and the procured structural design strategies can be utilized to design fracture-resistant structures. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The TSIC model facilitates the design of complex interface composites with stiff and compliant materials. • Control of the tensile and shear interface thickness allows tuning of the composites' stiffness and strength, respectively. • Fracture analysis reveals non-columnar fractures as a key to enhancing interface hardening in TSICs. • UV curing during printing results in a gradient elastic modulus at stiff-soft interfaces, enhancing strength compared to non-UV-cured samples. The rapid growth of polyjet additive manufacturing has propelled the 3D printing of multi-material polymer composites toward unprecedented applications. Interfaces in such composites play a paramount role in determining mechanical performance. This study delves into the crucial role of interfaces, employing VeroWhite and Agilus30Black materials to scrutinize the tensile and shear properties of stiff-soft interfaces. By applying these layers strategically, composites with multi-oriented interfaces were created, revealing the impact of soft material thickness and orientation on stiffness and strength. We identified columnar and non-columnar fracture mechanisms, shedding light on their correlation with interface hardening. Nanoindentation tests unveil the local interface properties, emphasizing the gradient change in elastic modulus when printed on the x -axis and the sharp drop on the z -axis. These findings offer valuable insights into material selection and interface optimization, providing a roadmap for achieving tailored mechanical properties in complex interface composites. [ABSTRACT FROM AUTHOR]

Many physically immobile plants develop passive yet ingenious strategies for active seed dispersal through self-deformation in response to external stimuli, such as humidity. These hygroscopic deformations are usually driven by the internal heterogeneous architecture, which provides valuable, inspiring information for the development of novel actuating systems. The Daucus carota compound umbel is an interesting structure showing a distinct hygroscopic deformation that operates at hierarchical levels among these plants. Here, we investigate the structure of the primary and secondary rays of the umbel associated with their deformation through mechanical analyses. We reveal that through controlling both the cellulose microfibril angle (MFA) and lignification, the multi-level bending behavior of the umbel is achieved, which contributes to efficient seed protection and dispersal. The primary rays generally show more significant bending curvature changes than the secondary rays, and within each level, the outer rays exhibit a larger motion amplitude than the middle and inner rays. Mechanical testing and theoretical analysis support that adjusting the lignin content within the ray structure compensates for the effect of the small differences in cellulose MFA on its bending behavior, which contributes to the overall hygroscopic deformation. Findings also show that the primary outer ray can generate reaction forces that are more than 700 times its weight, which is higher than that for the pine cone scales. The new insights from this work are instructive for bioinspired designs of complex, self-deforming structures and devices. The carrot (Daucus carota) compound umbels exhibit a unique hierarchical, hygroscopic deformation for seed dispersal among immobile plants. In this work, we elucidate that the multi-level bending behavior of the umbel is achieved through manipulating the cellulose microfibril angle (MFA) and lignification of the primary and secondary rays for the first time. We also discover that adjusting the degree of lignification compensates for the effect of small cellulose MFA differences on the bending behavior theoretically and experimentally. The primary outer rays deform in a highly efficient manner, in which reactions forces about more than 700 times its weight are generated. The findings presented are instructive for bioinspired designs of complex, self-deforming structures and devices. [ABSTRACT FROM AUTHOR]