The extrusion-based 3D printing system was used to fabricate the bioscaffold with hybrid hydrogels of gelatin and alginate (G/A), with different total solid concentrations (3%, 5%, and 7%) and G/A ...ratios (1:2, 1:1, and 2:1). Rheological properties were related to the 3D printability and shape retention capacity of the hybrid hydrogels. For extrusion-based 3D printing using the current platform, the materials that were considered 3D printable showed shear-thinning flow behavior. Also, the printable materials demonstrated a storage modulus (Gʹ) higher than the loss modulus (Gʹʹ), with a loss factor (tan δ = Gʹʹ/Gʹ) in the range of 0.48–0.58 during the frequency sweep of 15–40 rad/s, which is the corresponding frequency that can be related to our 3D printing settings. Texture profile analysis indicated that among the optimal formulas for 3D printing, the bioscaffold fabricated with the hybrid gels of 7% 1:2 G/A had the highest hardness and adhesiveness. After freeze-drying, the hardness increased significantly (p < 0.05). The 3D printed bioscaffold was also freeze-dried to extend the shelf life and enhance the mechanical properties of the fabricated structure, moisture content, and water activity reduced significantly after freeze-drying. The scanning electron microscopy (SEM) results demonstrated that the 3D printed scaffolds had porous structures, which has the potential to encapsulate and deliver other bioactive compounds, such as enzymes, vitamins, antioxidants, and probiotics.
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•Gelatin-alginate hybrid gels are promising bio-ink material in bioprinting.•Hydrogel's rheology and printability were correlated in extrusion-based 3D printing.•Optimal hybrid gels showed shear-thinning behavior and loss factor from 0.25 to 0.75.•Freeze-drying can improve shape retention and extend shelf-life of printed scaffold.•The integrated technology can be used to fabricate delivery systems in food application.
Abstract Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, leading to hyperthermia and suppression of tumor growths in mice. Herein, we show that in ...addition to the nanomaterial-mediated photothermal effects (NmPTT), gold nanoshells (including, nanocages, nanorod-in-shell and nanoparticle-in-shell) not only are able to absorb NIR light, but can also emit fluorescence, sensitize formation of singlet oxygen and exert nanomaterial-mediated photodynamic therapeutic (NmPDT) complete destruction of solid tumors in mice. The modes of NmPDT and NmPTT can be controlled and switched from one to the other by changing the excitation wavelength. In the in vitro experiments, gold nanocages and nanorod-in-shell show larger percentage of cellular deaths originating from NmPDT along with the minor fraction of NmPTT effects. In contrast, nanoparticle-in-shell exhibits larger fraction of NmPTT-induced cellular deaths together with minor fraction of NmPDT-induced apoptosis. Fluorescence emission spectra and DPBF quenching studies confirm the generation of singlet O2 upon NIR photoirradiation. Both NmPDT and NmPTT effects were confirmed by measurements of reactive oxygen species (ROS) and subsequent sodium azide quenching, heat shock protein expression (HSP 70), singlet oxygen sensor green (SOSG) sensing, changes in mitochondria membrane potential and apoptosis in the cellular experiments. In vivo experiments further demonstrate that upon irradiation at 980 nm under ultra-low doses (∼150 mW/cm2 ), gold nanocages mostly exert NmPDT effect to effectively suppress the B16F0 melanoma tumor growth. The combination of NmPDT and NmPTT effects on destruction of solid tumors is far better than pure NmPTT effect by 808 nm irradiation and also doxorubicin. Overall, our study demonstrates that gold nanoshells can serve as excellent multi-functional theranostic agents (fluorescence imaging + NmPDT + NmPTT) upon single photon NIR light excitation under ultra-low laser doses.
Since early diagnosis of sepsis may assist clinicians in initiating timely, effective, and prognosis-improving antibiotic therapy, we developed an integrated microfluidic chip (IMC) for rapid ...isolation of both Gram-positive and Gram-negative bacteria from blood. The device comprised a membrane-based filtration module (90 min operating time), a bacteria-capturing module using a micro-mixer containing magnetic beads coated with "flexible neck" regions of mannose-binding lectin proteins for bacteria capture (20 min), and a miniature polymerase chain reaction (PCR) module for bacteria identification (90 min
via
TaqMan® probe technology). The filter separated all white blood cells and 99.5% of red blood cells from bacteria, which were captured at rates approaching 85%. The PCR assay's limit of detection was 5 colony-forming units (CFU) per reaction, and the entire process was completed in only 4 h. Since this is far less than that for culture-based approaches, this IMC may serve as a promising device for detection of sepsis.
Isolation and identification of bacteria from human blood were automated on an integrated microfluidic system for sepsis-inducing bacteria.
Background: In Taiwan, infective native aortic aneurysms (INAAs) are relatively common, so the aim of present study was to demonstrate the comparative outcomes of endovascular repair for thoracic and ...abdominal INAAs.Methods and Results: Patients with naïve thoracic or abdominal INAAs managed with endovascular repair between 2001 and 2018 were included in this multicenter retrospective cohort. The confounding factors were adjusted with propensity score (PS). Of the 39 thoracic and 43 abdominal INAA cases, 41 (50%) presented with aneurysmal rupture, most of which were at the infrarenal abdominal (n=35, 42.7%) or descending thoracic aorta (n=25, 30.5%). Salmonella spp. was the most frequently isolated pathogen. The overall in-hospital mortality rate was 18.3%. The risks of in-hospital death and death due to rupture were significantly lower with thoracic INAAs (12.8% vs. 23.3%; PS-adjusted odds ratio (OR) 0.24, 95% confidence interval (CI) 0.06–0.96; 0.1% vs. 9.3%; PS-adjusted OR 0.11, 95% CI 0.01–0.90). During a mean follow-up of 2.5 years, the risk of all-cause death was significantly higher with thoracic INAAs (35.3% vs. 15.2%; PS-adjusted HR 6.90, 95% CI 1.69–28.19). Chronic kidney disease (CKD) was associated with death.Conclusions: Compared with thoracic INAAs, endovascular repair of abdominal INAAs was associated with a significantly higher in-hospital mortality rate. However, long-term outcomes were worse for thoracic INAAs, with CKD and infections being the most important predictor and cause of death, respectively.
Self-supporting designs that eliminate the need for structural supports can reduce manufacturing complexity caused by overhanging parts in additive manufacturing (AM). Traditionally, 45° is the ...minimum overhang angle required to ensure that designs can be manufactured without requiring any supporting structure. In this paper, a new self-supporting design method of AM based on topology optimization with overhang angle constraint is proposed. A self-supporting index established using a continuous logistic aggregate function is introduced to assess the supporting status of the specimen for AM process. This proposed self-supporting index is continuous and can be directly differentiated for sensitivity analysis without further mathematical transformations in the optimization formulation. Furthermore, it can be easily extended to a high-dimension aggregate (i.e., it can easily adapt to different overhang angles or self-supporting design domains). Numerical and fused deposition modeling (FDM) of a cantilever and MBB beam reveal that the self-supporting design can satisfy either general overhang angles or arbitrary orientation of AM deposition direction.
A novel integrated manufacturing approach of encapsulation, extrusion-based 3D printing, and freeze-drying was applied to develop a shelf-stable, convenient product that maintained the viability of ...probiotics. The two selected strains of probiotic organisms, including Bifidobacterium lactis and Lactobacillus acidophilus, were encapsulated at 109–1010 CFU/g within 3, 5, and 7 g/100 g alginate-gelatin (A/G) hydrogels in different A/G ratios (1/2, 1/1, and 2/1). The B. lactis cell viability exceeded 109 CFU/g after 3D printing, with less than 1 log reduction throughout the integrated manufacturing process. The viability of B. lactis was maintained at a level larger than 6 log CFU/g upon 8 weeks of storage at room temperature. While L. acidophilus showed lower viability, with 106 CFU/g after printing, and up to 2.5 log reduction by the end of the integrated manufacturing processes. After freeze-drying, the 3D-printed products changed from a semi-solid to a solid-like state, confirmed by increased hardness and decreased water activity. This study demonstrated that an integrated manufacturing consisting of encapsulation, 3D printing, and freeze-drying has the potential to produce a shelf-stable, convenient snack food or supplement product that can deliver live probiotics with customized strains and dosage.
•The integrated process was a feasible technology to protect probiotics in gel matrix.•Viable counts of the bacteria were above 6 log CFU/g after the integrated process.•The viability of B. lactis was maintained >6 log CFU/g upon 8 weeks of storage.
Package designs stimulate consumers visually and give rise to a sense of aesthetism, thus improving product visibility. In this study, emotions related to color combinations in packaging were ...addressed, cake packaging designs were tested, and affective design elements regarding styles and colors along with the diverse emotions that resulted were assessed and researched. Four experiments were conducted: Experiment 1 was on the affective characteristics related to types of colored boxes in packaging design; the best type of colored box for cakes was tested. In experiment 2, adjectives for emotions were compiled to identify adjectives for emotional responses to package designs. Experiment 3 was used to examine the fitness of single‐color boxes in packaging design; the colors of single‐color boxes were examined. In experiment 4, the focus was the fitness of dual‐color boxes in packaging design; an experiment on the best color combination was conducted with dual‐color boxes, and the results were then collected and analyzed to determine the fittest color combination for cake packaging design. According to the research findings, in the experiment on colored box types used in packaging design, the design with a five‐sided trapezoidal design was the most popular, followed by the colored box type with a rectangular handle in the middle; the selection of and experimentation on the adjectives for emotions revealed that Exquisite‐Rough was the fittest for the experiment, followed by Lively‐Dull; the fittest single‐color box was orange (Pantone715 C,L69.6,A37.0,B65.8), followed by gray (Pantone Gray Cool Gray 1C,L86.4,A0.1,B1.1); the fittest dual‐color box was in orange and orange red (Pantone Orange 021C, C,L60.0,A65.2,B71.4), followed by orange and black (Pantone Black C,L17.3,A0.8,B3.1). The experiment in this study focused on the color packaging of boxes for cakes; its results provide theoretical and practical references, for future research and orientation, regarding colors and types of colored boxes used for various products.
Browsing webpages on display devices such as computer monitors and smart phone screens has become commonplace. Color is the major visual mode to express the quality and sentiment of a webpage, and ...the most suitable webpage colors for viewing can be explored through the experimental analysis of different psychological perception of these colors. This study was divided into four experiments. Experiment 1 involved color emotion adjectives: participants selected the most suitable emotion adjectives for webpages. Experiment 2 concerned the color emotion characteristics of webpage color matching with a black background—participants selected the most popular color for a dynamic webpage with a black background. Experiment 3 focused on the visual fitness of the color scheme in webpages with a white background: participants selected the most popular color for a dynamic webpage with a white background. Experiment 4 concerned the optimal visual effect design of webpage composition; the researchers selected five geometric composition images to conduct a dynamic image webpage experiment to determine the influence of shapes on users' psychological response to webpages and identify the most popular dynamic image composition style. Semantic differential analysis was adopted to conduct psychological tests and investigate the psychological response of the respondents to different webpage colors and compositions. The results indicated that the most popular colors for webpages with a black background and white background were dodger blue (#1e90ff) and cyan (#00ffff), respectively, whereas the most suitable dynamic image composition was an elliptical design.
Non-covalent functionalization was used to functionalize graphene nanosheets (GNSs) through π–π stacking of pyrene molecules with a functional segmented polymer chain, which results in a remarkable ...improvement in the thermal conductivity of GNS-filled polymer composites. The functional segmented poly(glycidyl methacrylate) containing localized pyrene groups (Py-PGMA) was prepared by atom transfer radical polymerization, and Py-PGMA was characterized by nuclear magnetic resonance spectroscopy. Raman spectra, X-ray photoelectron spectroscopy and thermogravimetric analysis reveal the characteristics of Py-PGMA–GNS. Differential scanning calorimetry indicated that the functional groups on Py-PGMA–GNSs can generate covalent bonds with the epoxy matrix, and further form a cross-linked structure in Py-PGMA–GNS/epoxy composites. The Py-PGMA on the GNS surface not only plays an important role to facilitate a homogeneous dispersion in the polymer matrix but also improves the GNS–polymer interaction, which results in a high contact area. Consequently, the thermal conductivity of integrated Py-PGMA–GNS/epoxy composites exhibited a remarkable improvement and is much higher than epoxy reinforced by multi-walled carbon nanotubes or GNSs. The thermal conductivity of 4
phr Py-PGMA–GNS/epoxy has about 20% (higher than that of pristine GNS/epoxy) and 267% (higher than pristine MWCNT/epoxy).
Background The aim of this prospective study was to use direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to rapidly diagnose periprosthetic joint ...infections (PJIs). Method Synovial fluid was taken from 77 patients (80 joints, 41 hips and 39 knees) who met the International Consensus Meeting criteria for PJI, and inoculated into blood culture bottles (BCBs) and onto conventional swabs. Positive blood cultures were analyzed using either direct or routine MALDI-TOF MS. Pathogen identification and the time to identification was recorded. Differences between groups were analyzed using the Kruskal-Wallis test and Bonferroni's post-hoc test. Results Direct and routine MALDI-TOF MS both detected 64 positive results (80%), compared to 47 (59%) by conventional swabs (p = 0.002). Direct MALDI-TOF MS identified 85.3% of the gram-positive organisms and 92.3% of the gram-negative organisms. No fungi were identified by direct MALDI-TOF MS. In 17 BCBs that were flagged positive, identification by direct MALDI-TOF MS failed. Among the positive results in the direct MALDI-TOF MS group, Staphylococcus aureus accounted for 47%, followed by Staphylococcus epidermidis (17%), Escherichia coli (9%) and Klebsiella pneumoniae (9%). The median time to microorganism identification was significantly shorter with direct MALDI-TOF MS (12.7 h, IQR: 8.9-19.6 h) than with routine MALDI-TOF MS (39.5 h, IQR: 22.8-46.0 h) or swabs (44.4 h, IQR: 27.2-72.6 h) (p 0.0001). In pairwise comparisons, there were significant differences in the time of microorganism identification between direct MALDI-TOF MS and routine MALDI-TOF MS (p 0.0001) or swab culture (p 0.0001). There was no significant difference between routine MALDI-TOF MS and swab culture (p = 0.0268). Conclusion Compared with current laboratory practice, direct MALDI-TOF MS shortened the time to microorganism identification and had superior results compared to conventional swabs, except for fungi. Further studies should investigate whether the earlier administration of appropriate antimicrobial agents can improve the treatment outcomes of PJIs.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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