3D printed scaffolds of biosilica and spongin from marine sponges: analysis of genotoxicity and cytotoxicity for bone tissue repair.

Biosilica (BS) and spongin (SPG) from marine sponges are highlighted for their potential to promote bone regeneration. Moreover, 3D printing is introduced as a technology for producing bone grafts with optimized porous structures, allowing for better cell attachment, proliferation, and differentiation. Thus, this study aimed to characterize the BS and BS/SPG 3D printed scaffolds and to evaluate the biological effects in vitro. The scaffolds were printed using an ink containing 4 wt.% of sodium alginate. The physicochemical characteristics of BS and BS/SPG 3D printed scaffolds were analyzed by SEM, EDS, FTIR, porosity, evaluation of mass loss, and pH measurement. For in vitro analysis, the cellular viability of the MC3T3-E1 cell lineage was assessed using the AlamarBlue® assay and confocal microscopy, while genotoxicity and mineralization potential were evaluated through the micronucleus assay and Alizarin Red S, respectively. SEM analysis revealed spicules in BS, the fibrillar structure of SPG, and material degradation over the immersion period. FTIR indicated peaks corresponding to silicon oxide in BS samples and carbon oxide and amine in SPG samples. BS-SPG scaffolds exhibited higher porosity, while BS scaffolds displayed greater mass loss. pH measurements indicated a significant decrease induced by BS, which was mitigated by SPG over the experimental periods. In vitro studies demonstrated the biocompatibility and non-cytotoxicity of scaffold extracts. .Also, the scaffolds promoted cellular differentiation. The micronucleus test further confirmed the absence of genotoxicity. These findings suggest that 3D printed BS and BS/SPG scaffolds may possess desirable morphological and physicochemical properties, indicating in vitro biocompatibility.

Electrospun skin dressings for diabetic wound treatment: a systematic review.

Abstract: Diabetes mellitus is a metabolic disease characterized by persistent hyperglycemia associated with a lack of insulin production or insulin resistance. In diabetic patients, the capacity for healing is generally decreased, leading to chronic wounds. One of the most common treatments for chronic wounds is skin dressings, which serve as protection from infection, reduce pain levels, and stimulate tissue healing. Furthermore, electrospinning is one of the most effective techniques used for manufacturing skin dressings. Objective: The purpose of this study was to perform a systematic review of the literature to examine the effects of electrospun skin dressings from different sources in the process of healing skin wounds using in vivo experiments in diabetic rats. Methods: The search was carried out according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and the Medical Subject Headings (MeSH) descriptors were defined as "wound dressing," "diabetes," "in vivo," and "electrospun." A total of 14 articles were retrieved from PubMed and Scopus databases. Results: The results were based mainly on histological analysis and macroscopic evaluation, demonstrating moderate evidence synthesis for all experimental studies, showing a positive effect of electrospun skin dressings for diabetic wound treatment. Conclusion: This review confirms the significant benefits of using electrospun skin dressings for skin repair and regeneration. All the inks used were demonstrated to be suitable for dressing manufacturing. Moreover, in vivo findings showed full wound closure in most of the studies, with well-organized dermal and epidermal layers.

Laparoscopic Versus Open Gastrectomy for Advanced Gastric Cancer: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Laparoscopy-assisted gastrectomy (LAG) is a well-established surgical technique in treating patients with early gastric cancer. However, the efficacy and safety of LAG versus open gastrectomy (OG) in patients with advanced gastric cancer (AGC) remains unclear. METHODS: We systematically searched PubMed, Embase, and Cochrane Library in June 2023 for RCTs comparing LAG versus OG in patients with AGC. We pooled risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI) for binary and continuous endpoints, respectively. We performed all statistical analyses using R software version 4.3.1 and a random-effects model. RESULTS: Nine RCTs comprising 3827 patients were included. There were no differences in terms of intraoperative complications (RR 1.14; 95% CI 0.72 to 1.82), number of retrieved lymph nodes (MD -0.54 lymph nodes; 95% CI -1.18 to 0.09), or mortality (RR 0.91; 95% CI 0.30 to 2.83). LAG was associated with a longer operative time (MD 49.28 minutes; 95% CI 30.88 to 67.69), lower intraoperative blood loss (MD -51.24 milliliters; 95% CI -81.41 to -21.06), shorter length of stay (MD -0.83 days; 95% CI -1.60 to -0.06), and higher incidence of pancreatic fistula (RR 2.44; 95% CI 1.08 to 5.50). Postoperatively, LAG was also superior to OG in reducing bleeding rates (RR 0.44; 95% CI 0.22 to 0.86) and time to first flatus (MD -0.27 days; 95% CI -0.47 to -0.07), with comparable results in anastomotic leakage, wound healing issues, major complications, time to ambulation, or time to first liquid intake. In the long-term analyses at 3 and 5 years, there were no significant differences between LAG and OG in terms of overall survival (RR 0.99; 95% CI 0.96 to 1.03) or relapse-free survival (RR 0.99; 95% CI 0.94 to 1.04). CONCLUSION: This meta-analysis of RCTs suggests that LAG may be an effective and safe alternative to OG for treating AGC; albeit, it may be associated with an increased risk for pancreatic fistula.

Risk of false conformity decisions due to measurement uncertainty of Active Pharmaceutical Ingredient: A multiparametric evaluation

Abstract Medicines must be subject to physical, chemical, and biological analysis to guarantee their quality, safety, and effectiveness. Despite the efforts to ensure the reliability of analytical results, some uncertainty will always be associated with the measured value, which can lead to false decisions regarding conformity/non-conformity assessment. This work aims to calculate the specific risk of false decisions regarding conformity/non-conformity of acetaminophen oral solution dosage form. The acetaminophen samples from five different manufacturers (A, B, C, D, and E) were subject to an active pharmaceutical ingredient assay, density test, and dose per drop test according to the official compendia. Based on measured values and their respective uncertainties, the risk values were calculated using the Monte Carlo method implemented in an MS Excel spreadsheet. The results for two acetaminophen oral solution samples (C and D) provided an increased total risk value of false acceptance (33.1% and 9.6% for C and D, respectively). On the other hand, the results for the other three acetaminophen samples (A, B, and E) provided a negligible risk of false acceptance (0.004%, 0.025%, and 0.045% for A, B, and E, respectively). This indicates that measurement uncertainty is very relevant when a conformity assessment is carried out, and information on the risks of false decisions is essential to ensure proper decisions.

Spectrally multiplexed Hong-Ou-Mandel interference with weak coherent states.

We explore the suitability of a virtually imaged phased array as a spectral-to-spatial mode-mapper (SSMM) for applications in quantum communication such as a quantum repeater. To this end, we demonstrate spectrally resolved Hong-Ou-Mandel (HOM) interference with weak coherent states (WCSs). Spectral sidebands are generated on a common optical carrier, and WCSs are prepared in each spectral mode and sent to a beam splitter followed by two SSMMs and two single-photon detectors, allowing us to measure spectrally resolved HOM interference. We show that the so-called HOM dip can be observed in the coincidence detection pattern of matching spectral modes with visibilities as high as 45% (maximum 50% for WCSs). For unmatched modes, the visibility drops significantly, as expected. Due to the similarity between HOM interference and a linear-optics Bell-state measurement (BSM), this simple optical arrangement figures as a candidate for the implementation of a spectrally resolved BSM. Finally, we simulate the secret key generation rate using current and state-of-the-art parameters in a measurement-device-independent quantum key distribution scenario and explore the trade-off between rate and complexity of a spectrally multiplexed quantum communication link.

3D Printed Scaffolds Manufactured with Biosilica from Marine Sponges for Bone Healing in a Cranial Defect in Rats.

The inorganic part of marine sponges, called Biosilica (BS), presents an osteogenic potential and the ability of consolidating fractures. Moreover, 3D printing technique is highly effective for manufacturing scaffolds for tissue engineering proposals. Thus, the aims of this study were to characterize the 3D rinted scaffolds, to evaluate the biological effects in vitro and to investigate the in vivo response using an experimental model of cranial defects in rats. The physicochemical characteristics of 3D printed BS scaffolds were analyzed by FTIR, EDS, calcium assay, evaluation of mass loss and pH measurement. For in vitro analysis, the MC3T3-E1 and L929 cells viability was evaluated. For the in vivo evaluation, histopathology, morphometrical and immunohistochemistry analyses were performed in a cranial defect in rats. After the incubation, the 3D printed BS scaffolds presented lower values in pH and mass loss over time. Furthermore, the calcium assay showed an increased Ca uptake. The FTIR analysis indicated the characteristic peaks for materials with silica and the EDS analysis demonstrated the main presence of silica. Moreover, 3D printed BS demonstrated an increase in MC3T3-E1 and L929 cell viability in all periods analyzed. In addition, the histological analysis demonstrated no inflammation in days 15 and 45 post-surgery, and regions of newly formed bone were also observed. The immunohistochemistry analysis demonstrated increased Runx-2 and OPG immunostaining. Those findings support that 3D printed BS scaffolds may improve the process of bone repair in a critical bone defect as a result of stimulation of the newly formed bone.

3D printed wound constructs for skin tissue engineering: A systematic review in experimental animal models.

Wound dressings are one of the most used treatments for chronic wounds. Moreover, 3D printing has been emerging as a promising strategy for printing 3D printed wound constructs, being able of manufacturing multi layers, with a solid 3D structure. Although all these promising effects of 3D printed wound constructs, there is still few studies and limited understanding of the interaction of these dressings with skin tissue and their effect on the process of skin wound healing. In this context, the aim of this work was to perform a systematic review of the literature to examine the effects of 3D printed wound constructs on the process of skin wound healing in animal models. The articles were selected from three databases following Medical Subject Headings (MeSH) descriptors "3D printing," "skin," "wound," and "in vivo." After the selection, exclusion and inclusion criteria, nine articles were analyzed. This review confirms the significant benefits of using 3D printed wound constructs for skin repair and regeneration. All the used inks demonstrated the ability of mimicking the structure of skin tissue and promoting cell adhesion, proliferation, migration, and mobility. Furthermore, in vivo findings showed full wound closure in most of the studies, with well-organized dermal and epidermal layers.

Effect of thermal processing on the antigenicity of allergenic milk, egg and soy proteins.

The detection of allergenic proteins and the influence of processing on the structure and antigenicity of these proteins are relevant topics. Using commercial enzyme-linked immunosorbent assay kits, this study aimed to evaluate the degradation profiles of milk, egg and soy proteins during the processing of semisweet biscuits. The formulations were baked under different conditions according to a complete factorial experiment that included a three-level temperature factor and a six-level time factor. ß-lactoglobulin and egg white proteins were severely degraded, the degradation of casein was intermediate, and soy proteins were the most stable. Complete allergen protein degradation was found under only the extreme baking conditions, which resulted in products that were not sensorily acceptable. Residual levels of the proteins were detected after baking, indicating that this thermal processing reduced but did not eliminate the antigenicity of these proteins; thus, baking cannot be considered a strategy to protect allergic consumers.

Long-Lived Solid-State Optical Memory for High-Rate Quantum Repeaters.

We argue that long optical storage times are required to establish entanglement at high rates over large distances using memory-based quantum repeaters. Triggered by this conclusion, we investigate the 795.325 nm^{3} H_{6}↔^{3}H_{4} transition of Tm:Y_{3}Ga_{5}O_{12} (Tm:YGG). Most importantly, we find that the optical coherence time can reach 1.1 ms, and, using laser pulses, we demonstrate optical storage based on the atomic frequency comb protocol during up to 100 µs as well as a memory decay time T_{m} of 13.1 µs. Possibilities of how to narrow the gap between the measured value of T_{m} and its maximum of 275 µs are discussed. In addition, we demonstrate multiplexed storage, including with feed-forward selection, shifting and filtering of spectral modes, as well as quantum state storage using members of nonclassical photon pairs. Our results show the potential of Tm:YGG for creating multiplexed quantum memories with long optical storage times, and open the path to repeater-based quantum networks with high entanglement distribution rates.

Alignment-free characterization of polarizing beamsplitters.

Traditional methods for measurement of polarizing beamsplitter (PBS) parameters, especially the extinction ratio, require highly polarized light sources, alignment procedures, and/or experimental parameters that change over time, such as polarization rotations. In this work, a new method is presented that employs unpolarized light and a Faraday mirror. It is shown that precise extinction ratio and insertion loss values can be achieved in three single-sweep measurements without any alignment requirements or time-varying signals of any kind.

Random bit generation using coherent state and threshold detectors at 1550 nanometers.

We theoretically propose and experimentally validate a practical random bit generation method based on the detections of a coherent state in the few-photon regime by a gated single-photon threshold detector, operating at the telecom wavelength of 1550 nanometers. By fine tuning the mean number of photons per pulse of a laser beam directed to the single-photon detector, a 50-50 chance of detection or no-detection is reached; under this condition, detections inside the gate window are treated as "1"s, while "0"s are associated with the absence of detections. The same method could also be applied in a free-running single-photon detector for increased throughput by chopping the light signal instead of gating the detector. Both hardware implementations yielded bit strings, which were evaluated by a standard randomness test suite with good confidence. Despite the yet low rates achieved by the proposed method, its hardware compatibility with quantum key distribution setups makes it an interesting candidate for random number generation within the context of practical quantum communications.

Time-polarization multiplexing for increased output power of semiconductor optical amplifiers in the pulsed regime.

We present a setup capable of overcoming the saturation output power of semiconductor optical amplifiers operating in the pulsed regime. The concept is to couple different time delays to orthogonal polarization modes, amplify the pulses multiplexed in time, and use the polarization information to recombine them into a single high-power optical pulse. Making use of a single amplifier and two polarizing beam splitters, we were able to amplify pulses with as much as 1.9 dB above the saturation output power of the device. We also show that the method is scalable if any number of polarizing beam splitters is available, where each extra device contributes roughly 1.9 dB to the overall above-saturation amplification factor.