Size-dependent influences of nano- and micro-plastics exposure on feeding, antioxidant systems, and organic sulfur compounds in ciliate Uronema marinum.

Protozoa play a pivotal role in the microbial cycle, and ciliated protozoan grazing habits are associated with dimethyl sulfide (DMS) cycle. Many studies have explored the impacts of nanoplastics (NPs) and microplastics (MPs) on ecotoxicological effects of ciliates. However, limited research exists on NPs and MPs influences on the production of organic sulfur compounds. The impact of NPs and MPs on the production of dimethyl sulfoxide (DMSO) and carbonyl sulfide (COS) remains unclear. Therefore, we examined the impacts of three concentrations (1 × 105, 5 × 105, and 1 × 106 items/mL) of polystyrene (PS) NPs (50 nm) and MPs (1 and 5 µm) on the ecotoxicology and DMS/dimethylsulfoniopropionate (DMSP)/DMSO/COS production in the ciliate Uronema marinum. NPs and MPs exposure were found to reduce the abundance, growth rate, volume, and biomass of U. marinum. Additionally, NPs and MPs increased the superoxide anion radical (O2˙─) production rates and malondialdehyde (MDA) contents (24 h), leading to a decline in glutathione (GSH) content and an ascend in superoxide dismutase (SOD) activity to mitigate the effects of reactive oxygen species (ROS). Exposure to PS NPs and MPs decreased the ingestion rates of algae by 7.5‒14.4%, resulting in decreases in DMS production by 56.8‒85.4%, with no significant impact on DMSO production. The results suggest a distinct pathway for the production of DMSO or COS compared to DMS. These findings help us to understand the NPs and MPs impacts on the marine ecosystem and organic sulfur compound yield, potentially influencing the global climate.

Cryopreservation of human kidney organoids.

Recent advances in stem cell research have led to the creation of organoids, miniature replicas of human organs, offering innovative avenues for studying diseases. Kidney organoids, with their ability to replicate complex renal structures, provide a novel platform for investigating kidney diseases and assessing drug efficacy, albeit hindered by labor-intensive generation and batch variations, highlighting the need for tailored cryopreservation methods to enable widespread utilization. Here, we evaluated cryopreservation strategies for kidney organoids by contrasting slow-freezing and vitrification methods. 118 kidney organoids were categorized into five conditions. Control organoids followed standard culture, while two slow-freezing groups used 10% DMSO (SF1) or commercial freezing media (SF2). Vitrification involved V1 (20% DMSO, 20% Ethylene Glycol with sucrose) and V2 (15% DMSO, 15% Ethylene Glycol). Assessment of viability, functionality, and structural integrity post-thawing revealed notable differences. Vitrification, particularly V1, exhibited superior viability (91% for V1, 26% for V2, 79% for SF1, and 83% for SF2 compared to 99.4% in controls). 3D imaging highlighted distinct nephron segments among groups, emphasizing V1's efficacy in preserving both podocytes and tubules in kidney organoids. Cisplatin-induced injury revealed a significant reduction in regenerative capacities in organoids cryopreserved by flow-freezing methods, while the V1 method did not show statistical significance compared to the unfrozen controls. This study underscores vitrification, especially with high concentrations of cryoprotectants, as an effective approach for maintaining kidney organoid viability and structure during cryopreservation, offering practical approaches for kidney organoid research.

Optimizing the feasibility of polyvinyl alcohol-potassium iodine gel for medical dosimeter.

This work aims to improve the post stabilty of reusable potassium iodide hydrogel dosimter. A reusable and low-cost radiochromic dosimeter containing a gel matrix of polyvinyl alcohol, potassium iodide dye, froctose as reducing agent and glutaraldehyde as cross-linking agent was developed for dose calibration in radiotherapy. The gel samples were exposed to different absorbed doses using a medical linear acceleration. UV-vis Spectrophotometry was utilized to investigate the changes in optical-properties of irradiated gels with regard to peak wavelength of 353 nm. The stability of the gel (one of the most limitation of using this dosimeter) was improved significantly by the addition of certain concentrations of dimethyl sulfoxide. The two-dimensional optical imaging system of charge-coupled-device (CCD) camera with a uniform RGB light-emitting-diode (LED) array source was used for diffusion coefficient purpose using two dimensional gel template. The value of diffusion coefficient reported is significant and highly reduced compared with other dosimeters reported in the literatures. Moreover, heating the improved gels to certain temperatures results in resetting their optical properties, which makes it possible to reuse for multiple times.

A rapid spectrophotometric test for assessing skin sensitization potential of chemicals by using N-acetyl-L-cysteine methyl ester in chemico.

During the key event 1 of skin sensitization defined as covalent binding or haptenization of sensitizer to either thiol or amino group of skin proteins, a sensitizer not only covalently binds with skin proteins but also interacts with nucleophilic small molecules such as glutathione (GSH). Although GSH would not be directly associated with skin sensitization, this interaction may be applied for developing an alternative test method simulating key event 1, haptenization. Thus, the aim of the present study was to examine whether N-acetyl-L-cysteine methyl ester (NACME), a thiol-containing compound, was selected as an electron donor to determine whether NACME reacted with sensitizers. Following a reaction of NACME with a sensitizer in a 96-well plate, the remaining NACME was measured spectrophotometrically using 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB). Following the optimization of test conditions with two different vehicles, such as acetonitrile (ACN) and dimethyl sulfoxide (DMSO), 64 test chemicals were tested to determine the predictive capacity of current NACME test method. The results obtained showed, the predictive capacity of 94.6% sensitivity, 88.9% specificity, and 92.2% accuracy utilizing DMSO as a vehicle with a cutoff NACME depletion of 5.85%. The three parameters were also over 85% in case of ACN. These values were comparable to or better than other OECD-approved test methods. Data demonstrated that a simple thiol-containing compound NACME might constitute as a reliable candidate for identifying reactive skin sensitizers, and that this method be considered as practical method as a screening tool for assessing a chemical's tendency to initiate skin sensitization.

Zinc Iodide Dimethyl Sulfoxide Reduces Collagen Deposition by Increased Matrix Metalloproteinase-2 Expression and Activity in Lung Fibroblasts.

Chronic inflammatory lung diseases are characterized by disease-specific extracellular matrix accumulation resulting from an imbalance of matrix metalloproteinases (MMPs) and their inhibitors. Zinc is essential for the function of MMPs, and zinc deficiency has been associated with enhanced tissue remodeling. This study assessed if zinc iodide (ZnI) supplementation through dimethyl sulfoxide (DMSO) modifies the action of MMPs in isolated human lung fibroblasts. The expression and activity of two gelatinases, MMP-2 and MMP-9, were determined by gelatin zymography and enzyme-linked immuno-sorbent assay (ELISA). Collagen degradation was determined by cell-based ELISAs. Collagen type I and fibronectin deposition was stimulated by human recombinant tumor growth factor ß1 (TGF-ß1). Untreated fibroblasts secreted MMP-2 but only minute amounts of MMP-9. TGF-ß1 (5 ng/mL) reduced MMP-2 secretion, but stimulated collagen type I and fibronectin deposition. All the effects of TGF-ß1 were significantly reduced in cells treated with ZnI-DMSO over 24 h, while ZnI and DMSO alone had a lower reducing effect. ZnI-DMSO alone did not increase MMP secretion but enhanced the ratio of active to inactive of MMP-2. ZnI alone had a lower enhancing effect than ZnI-DMSO on MMP activity. Furthermore, MMP-2 activity was increased by ZnI-DMSO and ZnI in the absence of cells. Soluble collagen type I increased in the medium of ZnI-DMSO- and ZnI-treated cells. Blocking MMP activity counteracted all the effects of ZnI-DMSO. Conclusion: The data suggest that the combination of ZnI with DMSO reduces fibrotic processes by increasing the degradation of collagen type I by up-regulating the activity of gelatinases. Thus, the combination of ZnI with DMSO might be considered for treatment of fibrotic disorders of the lung. DMSO supported the beneficial effects of ZnI.

Phosphate-Buffered Saline and Dimethyl Sulfoxide Enhance the Antivenom Action of Ruthenium Chloride against Crotalus atrox Venom in Human Plasma-A Preliminary Report.

Ruthenium chloride (RuCl3) is widely utilized for synthesis and catalysis of numerous compounds in academia and industry and is utilized as a key molecule in a variety of compounds with medical applications. Interestingly, RuCl3 has been demonstrated to modulate human plasmatic coagulation and serves as a constituent of a compounded inorganic antivenom that neutralizes the coagulopathic effects of snake venom in vitro and in vivo. Using thrombelastography, this investigation sought to determine if RuCl3 inhibition of the fibrinogenolytic effects of Crotalus atrox venom could be modulated by vehicle composition in human plasma. Venom was exposed to RuCl3 in 0.9% NaCl, phosphate-buffered saline (PBS), or 0.9% NaCl containing 1% dimethyl sulfoxide (DMSO). RuCl3 inhibited venom-mediated delay in the onset of thrombus formation, decreased clot growth velocity, and decreased clot strength. PBS and DMSO enhanced the effects of RuCl3. It is concluded that while a Ru-based cation is responsible for significant inhibition of venom activity, a combination of Ru-based ions containing phosphate and DMSO enhances RuCl3-mediated venom inhibition. Additional investigation is indicated to determine what specific Ru-containing molecules cause venom inhibition and what other combinations of inorganic/organic compounds may enhance the antivenom effects of RuCl3.

A deep eutectic solvent is an effective cryoprotective agent for platelets.

The most widely used method of platelet cryopreservation requires the addition of dimethyl sulfoxide (DMSO; Me2SO) as a cryoprotective agent (CPA) and pre-freeze removal of Me2SO before freezing to mitigate toxicity. However, alternative CPAs such as deep eutectic solvents (DES), which are less toxic could simplify this process. The aim of this study was to determine the effectiveness of a Proline-Glycerol (Prol-Gly 1:3) DES as a platelet CPA. Platelets were cryopreserved at -80 °C using 10 % Prol-Gly 1:3 (DES; n = 6), or in the absence of a cryoprotectant (no CPA; n = 6). Platelets were also cryopreserved according to the gold-standard blood-banking method using 5.5 % Me2SO (n = 6), with centrifugation and pre-freeze removal of the excess Me2SO. Platelet quality was assessed by flow cytometry and thromboelastography (TEG). Post-thaw recovery was similar between the three groups. The abundance of labile platelet glycoproteins GPIbα and GPVI were highest in the DES group, however, markers of activation (CD62P and annexin-V) were also higher in this group. In terms of function, the strength of the clot (maximum amplitude; TEG) and extent of clot retraction was better with DES platelets compared to no CPA, but lower than Me2SO platelets. DES provides a cryoprotective advantage to platelets when compared to no CPA. Importantly, when compared to Me2SO platelets, most quality parameters were similar in DES platelets. The major advantage with using a DES is biocompatibility, therefore it does not need to be removed prior to transfusion. This greatly simplifies the freezing and thawing process, avoiding the toxic effects of Me2SO.

Efficient Reductive N-11C-Methylation Using Arylamines or Alkylamines and In Situ-Generated [11C]Formaldehyde From [11C]Methyl Iodide.

Reductive N-11C-methylation using [11C]formaldehyde and amines has been used to prepare N-11C-methylated compounds. However, the yields of the N-11C-methylated compounds are often insufficient. In this study, we developed an efficient method for base-free reductive N-11C-methylation that is applicable to a wide variety of substrates, including arylamines bearing electron-withdrawing and electron-donating substituents. A 2-picoline borane complex, which is a stable and mild reductant, was used. Dimethyl sulfoxide was used as the primary reaction solvent, and glacial acetic acid or aqueous acetic acid was used as a cosolvent. While reductive N-11C-methylation efficiently proceeded under anhydrous conditions in most cases, the addition of water to the reductive N-11C-methylation generally increased the yield of the N-11C-methylated compounds. Substrates with hydroxy, carboxyl, nitrile, nitro, ester, amide, and phenone moieties and amine salts were applicable to the reaction. This proposed method for reductive N-11C-methylation should be applicable to a wide variety of substrates, including thermo-labile and base-sensitive compounds because the reaction was performed under relatively mild conditions (70°C) without the need for a base.

Gas-Phase Formation of Sulfurous Acid (H2SO3) in the Atmosphere.

Sulfurous acid (H2SO3) is known to be thermodynamically instable decomposing into SO2 and H2O. All attempts to detect this elusive acid in solution failed up to now. Reported H2SO3 formation from an experiment carried out in a mass spectrometer as well as results from theoretical calculations, however, indicated a possible kinetic stability in the gas phase. Here, it is shown experimentally that H2SO3 is formed in the OH radical-initiated gas-phase oxidation of methanesulfinic acid (CH3S(O)OH) at 295±0.5 K and 1 bar of air with a molar yield of 53 - 17 + 7 ${{53}_{-17}^{+\ 7}}$ %. Further main products are SO2, SO3 and methanesulfonic acid. CH3S(O)OH represents an important intermediate product of dimethyl sulfide oxidation in the atmosphere. Global modeling predicts an annual H2SO3 production of ∼8 million metric tons from the OH+CH3S(O)OH reaction. The investigated H2SO3 depletion in the presence of water vapor results in k(H2O+H2SO3) <3×10-18 cm3 molecule-1 s-1, which indicates a lifetime of at least one second for atmospheric humidity. This work provides experimental evidence that H2SO3, once formed in the gas phase, is kinetically stable enough to allow its characterization and subsequent reactions.

Morphological and Neurological Impairments Induced by Chronic Administration of Dimethyl Sulfoxide in Mice.

We studied the influence of DMSO administered ad libitum with drinking water in concentrations of 0.01, 0.1, and 1% for 4 and 6 weeks on pain sensitivity, motor coordination, and myelin content in the corpus callosum of C57BL/6 mice. After 6-week administration, DMSO in all studied concentrations decreased myelin content in the corpus callosum. Moreover, 4-week administration of 0.1% DMSO and 6-week administration of 1% DMSO increased the latency to fall in the rotarod test by 3.1 (p<0.05) and 5.1 (p<0.001) times, respectively. After 4-week administration of DMSO in concentrations of 0.01 and 0.1%, the latency of the tail flick response increased by 2.1 (p<0.05) and 1.8 times (p<0.001), respectively. Administration of DMSO in concentrations of 0.01 and 1% for 6 weeks led to a decrease of this parameter by 2.7 (p<0.05) and 3.8 times (p<0.01), respectively. Thus, DMSO in all studied concentrations decreased myelin content in the corpus callosum of C57BL/6 mice and modified motor coordination and pain sensitivity of animals.

Central Carbon Metabolism in Candida albicans Biofilms Is Altered by Dimethyl Sulfoxide.

The effect of dimethyl sulfoxide (DMSO) on fungal metabolism has not been well studied. This study aimed to evaluate, by metabolomics, the impact of DMSO on the central carbon metabolism of Candida albicans. Biofilms of C. albicans SC5314 were grown on paper discs, using minimum mineral (MM) medium, in a dynamic continuous flow system. The two experimental conditions were control and 0.03% DMSO (v/v). After 72 h of incubation (37 °C), the biofilms were collected and the metabolites were extracted. The extracted metabolites were subjected to gas chromatography-mass spectrometry (GC/MS). The experiment was conducted using five replicates on three independent occasions. The GC/MS analysis identified 88 compounds. Among the 88 compounds, the levels of 27 compounds were markedly different between the two groups. The DMSO group exhibited enhanced levels of putrescine and glutathione and decreased levels of methionine and lysine. Additionally, the DMSO group exhibited alterations in 13 metabolic pathways involved in primary and secondary cellular metabolism. Among the 13 altered pathways, seven were downregulated and six were upregulated in the DMSO group. These results indicated a differential intracellular metabolic profile between the untreated and DMSO-treated biofilms. Hence, DMSO was demonstrated to affect the metabolic pathways of C. albicans. These results suggest that DMSO may influence the results of laboratory tests when it is used as a solvent. Hence, the use of DMSO as a solvent must be carefully considered in drug research, as the effect of the researched drugs may not be reliably translated into clinical practice.

DMSO and Its Role in Differentiation Impact Efficacy of Human Adenovirus (HAdV) Infection in HepaRG Cells.

Differentiated HepaRG cells are popular in vitro cell models for hepatotoxicity studies. Their differentiation is usually supported by the addition of dimethyl sulfoxide (DMSO), an amphipathic solvent widely used in biomedicine, for example, in potential novel therapeutic drugs and cryopreservation of oocytes. Recent studies have demonstrated drastic effects, especially on epigenetics and extracellular matrix composition, induced by DMSO, making its postulated inert character doubtful. In this work, the influence of DMSO and DMSO-mediated modulation of differentiation on human adenovirus (HAdV) infection of HepaRG cells was investigated. We observed an increase in infectivity of HepaRG cells by HAdVs in the presence of 1% DMSO. However, this effect was dependent on the type of medium used for cell cultivation, as cells in William's E medium showed significantly stronger effects compared with those cultivated in DMEM. Using different DMSO concentrations, we proved that the impact of DMSO on infectability was dose-dependent. Infection of cells with a replication-deficient HAdV type demonstrated that the mode of action of DMSO was based on viral entry rather than on viral replication. Taken together, these results highlight the strong influence of the used cell-culture medium on the performed experiments as well as the impact of DMSO on infectivity of HepaRG cells by HAdVs. As this solvent is widely used in cell culture, those effects must be considered, especially in screening of new antiviral compounds.

Modulation of bacterial membranes and cellular macromolecules by dimethyl sulfoxide: A dose-dependent study providing novel insights.

Using Escherichia coli as a model, this manuscript delves into the intricate interactions between dimethyl sulfoxide (DMSO) and membranes, cellular macromolecules, and the effects on various aspects of bacterial physiology. Given DMSO's wide-ranging use as a solvent in microbiology, we investigate the impacts of both non-growth inhibitory (1.0 % and 2.5 % v/v) and slightly growth-inhibitory (5.0 % v/v) concentrations of DMSO. The results demonstrate that DMSO causes alterations in bacterial membrane potential, influences the electrochemical characteristics of the cell surface, and exerts substantial effects on the composition and structure of cellular biomolecules. Genome-wide gene expression data from DMSO-treated E. coli was used to further investigate and bolster the results. The findings of this study provide valuable insights into the complex relationship between DMSO and biological systems, with potential implications in drug delivery and cellular manipulation. However, it is essential to exercise caution when utilizing DMSO to enhance the solubility and delivery of bioactive compounds, as even at low concentrations, DMSO exerts non-inert effects on cellular macromolecules and processes.

Resource Recovery of Spent Lithium-Ion Battery Cathode Materials by a Supercritical Carbon Dioxide System.

The increasing global market size of high-energy storage devices due to the boom in electric vehicles and portable electronics has caused the battery industry to produce a lot of waste lithium-ion batteries. The liberation and de-agglomeration of cathode material are the necessary procedures to improve the recycling derived from spent lithium-ion batteries, as well as enabling the direct recycling pathway. In this study, the supercritical (SC) CO2 was innovatively adapted to enable the recycling of spent lithium-ion batteries (LIBs) based on facilitating the interaction with a binder and dimethyl sulfoxide (DMSO) co-solvent. The results show that the optimum experimental conditions to liberate the cathode particles are processing at a temperature of 70 °C and 80 bar pressure for a duration of 20 min. During the treatment, polyvinylidene fluoride (PVDF) was dissolved in the SC fluid system and collected in the dimethyl sulfoxide (DMSO), as detected by the Fourier Transform Infrared Spectrometer (FTIR). The liberation yield of the cathode from the current collector reaches 96.7% under optimal conditions and thus, the cathode particles are dispersed into smaller fragments. Afterwards, PVDF can be precipitated and reused. In addition, there is no hydrogen fluoride (HF) gas emission due to binder decomposition in the suggested process. The proposed SC-CO2 and co-solvent system effectively separate the PVDF from Li-ion battery electrodes. Thus, this approach is promising as an alternative pre-treatment method due to its efficiency, relatively low energy consumption, and environmental benign features.

In Situ Formed Robust Solid Electrolyte Interphase with Organic-Inorganic Hybrid Layer for Stable Zn Metal Anode.

Stabilizing the Zn anode/electrolyte interface is critical for advancing aqueous zinc ion storage technologies. Addressing this challenge helps minimize parasitic reactions and controls the formation of Zn dendrites, which is fundamental to achieving highly reversible Zn electrochemistry. In this study, 2% by volume of dimethyl sulfoxide (DMSO) is introduced into the baseline zinc sulfate (ZS) electrolyte, which acts as an efficient regulator to form a robust solid-electrolyte interphase (SEI) on the Zn anode. This innovative approach enables uniform Zn deposition and does not substantially modify the Zn2+ solvation structure. The Zn||Zn symmetric cell exhibits an extended cycle life of nearly one calendar year (>8500 h) at a current density of 0.5 mA cm-2 and an areal capacity of 0.5 mAh cm-2. Impressive full cell performance can be achieved. Specifically, the Zn||VS2 full cell achieves an areal capacity of 1.7 mAh cm-2, with a superior negative-to-positive capacity ratio of 2.5, and an electrolyte-to-capacity ratio of 101.4 µL mAh-1, displaying remarkable stability over 1000 cycles under a high mass loading of 11.0 mg cm-2 without significant degradation. This innovative approach in electrolyte engineering provides a new perspective on in situ SEI design and furthers the understanding of Zn anode stabilization.

Raloxifene-driven benzothiophene derivatives: Discovery, structural refinement, and biological evaluation as potent PPARγ modulators based on drug repurposing.

By virtue of the drug repurposing strategy, the anti-osteoporosis drug raloxifene was identified as a novel PPARγ ligand through structure-based virtual high throughput screening (SB-VHTS) of FDA-approved drugs and TR-FRET competitive binding assay. Subsequent structural refinement of raloxifene led to the synthesis of a benzothiophene derivative, YGL-12. This compound exhibited potent PPARγ modulation with partial agonism, uniquely promoting adiponectin expression and inhibiting PPARγ Ser273 phosphorylation by CDK5 without inducing the expression of adipongenesis associated genes, including PPARγ, aP2, CD36, FASN and C/EBPα. This specific activity profile resulted in effective hypoglycemic properties, avoiding major TZD-related adverse effects like weight gain and hepatomegaly, which were demonstrated in db/db mice. Molecular docking studies showed that YGL-12 established additional hydrogen bonds with Ile281 and enhanced hydrogen-bond interaction with Ser289 as well as PPARγ Ser273 phosphorylation-related residues Ser342 and Glu343. These findings suggested YGL-12 as a promising T2DM therapeutic candidate, thereby providing a molecular framework for the development of novel PPARγ modulators with an enhanced therapeutic index.

Exploring the neuroprotective activity of a lignanamides-rich extract in human neuroblastoma SH-SY5Y cells under dimethyl sulfoxide-induced stress.

Introduction: Dimethyl sulfoxide (DMSO) is widely used as a diluent and/or solvent for pharmacological compounds. Furthermore, DMSO crosses the blood-brain barrier acting on the nervous system. The natural compounds phenylamides and lignanamides (LnHS) have protective effects on neuronal health, being promising neuroprotective candidates. In this scenario, we evaluated the impact of DMSO and/or LnHS on SH-SY5Y and U-87 cells, taken as in vitro model of neurons and glia. Methods: Cells were treated with DMSO and/or LnHS at different doses and proliferation (MTT and trypan blue counting, colony forming ability, autophagy, oxidative stress (NO, ROS determination) and inflammatory (IL8, IL6, TNFα mRNA expression) response was evaluated. Results: We found that DMSO reduces both neuronal and glial cell viability, while LnHS does not affect viability of SH-SY5Y cells but reduces that of U-87 cells. Therefore, we focused on SHSY5Y cells and investigated whether LnHS could counteract DMSO toxicity. LnHS partially attenuates the inhibitory effects of DMSO on cell viability and restores the colony-forming ability of SH-SY5Y cells exposed to DMSO. Furthermore, we found that co-administration of LnHS modulates the expression of SIRT3 and SOD2 enzymes, reduces nitrite release and ROS generation increasing IL-8 levels. Interestingly, co-administration of LnHS counteracts the DMSO-induced production of IL-6, while no modification in TNF-α was found. Discussion: Our study indicates LnHS as a potential feasible compound to support neuronal health as it counteracts DMSO induced cytotoxic effects by improving SH-SY5Y cells survival. Further studies are needed to clarify the molecular mechanisms underlying the LnHS biological activities.

Effects of vehicles on the physical properties and biocompatibility of premixed calcium silicate cements.

Premixed calcium silicate cements (pCSCs) contain vehicles which endow fluidity and viscosity to CSCs. This study aimed to investigate the effects of three vehicles, namely, polyethylene glycol (PEG), propylene glycol (PG), and dimethyl sulfoxide (DMSO), on the physicochemical properties and biocompatibility of pCSCs. The setting time, solubility, expansion rate, and mechanical strength of the pCSCs were evaluated, and the formation of calcium phosphate precipitates was assessed in phosphate-buffered saline (PBS). The effects of pCSC extracts on the osteogenic differentiation of mesenchymal stem cells (MSCs) were investigated. Finally, the tissue compatibility of pCSCs in rat femurs was observed. CSC containing PEG (CSC-PEG) exhibited higher solubility and setting time, and CSC-DMSO showed the highest expansion rate and mechanical strength. All pCSCs generated calcium phosphate precipitates. The extract of CSC-PG induced the highest expressions of osteogenic markers along with the greatest calcium deposites. When implanted in rat femurs, CSC-PEG was absorbed considerably, whereas CSC-PG remained relatively unaltered inside the femur.

Chitin nanofibrils assisted 3D printing all-chitin hydrogels for wound dressing.

The direct ink writing technique used in 3D printing technology is generally applied to designing biomedical hydrogels. Herein, we proposed a strategy for preparing all-chitin-based inks for wound dressing via direct ink writing technique. The ß-chitin nanofibers (MACNF) with a high aspect ratio were applied as a nanofiller to modulate the rheological properties of the alkaline dissolved chitin solution. The printing fidelity significantly depends on the MACNF introduction amount to the composite ink. 5-10 wt% MACNF ratio showed superior printing performance. The printed scaffold showed a uniform micron-sized pore structure and a woven network of nanofibers. Due to the good biocompatibility of chitin and the stereoscopic spatial skeleton, this scaffold showed excellent performance as a wound dressing, which can promote cell proliferation, collagen deposition and the angiogenesis of wounds, demonstrating its potential in biomedical applications. This approach successfully balanced the chitinous printability and biofunctions.

Effect of DMSO on Structural Properties of DMPC and DPPC Liposome Suspensions.

The study and characterization of the biophysical properties of membranes and drug-membrane interactions represent a critical step in drug development, as biological membranes act as a barrier that the drug must overcome to reach its active site. Liposomes are widely used in drug delivery to circumvent the poor aqueous solubility of most drugs, improving systemic bioavailability and pharmacokinetics. Further, they can be targeted to deliver to specific disease sites, thus decreasing drug load, and reducing side effects and poor adherence to treatment. To improve drug solubility during liposome preparation, DMSO is the most widely used solvent. This raises concern about the potential effect of DMSO on membranes and leads us to investigate, using DSC and EPR, the influence of DMSO on the behavior of lipid model membranes of DMPC and DPPC. In addition, we tested the influence of DMSO on drug-membrane interaction, using compounds with different hydrophobicity and varying DMSO content, using the same experimental techniques. Overall, it was found that with up to 10% DMSO, changes in the bilayer fluidity or the thermotropic properties of the studied liposomes were not significant, within the experimental uncertainty. For higher concentrations of DMSO, there is a stabilization of both the gel and the rippled gel phases, and increased bilayer fluidity of DMPC and DPPC liposomes leading to an increase in membrane permeability.