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.

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.

Cryopreservation with DMSO affects the DNA integrity, apoptosis, cell cycle and function of human bone mesenchymal stem cells

Cryopreservation (CP) enables pooling and long-term banking of various types of cells, which is indispensable for the cell therapeutics. Dimethyl sulfoxide (DMSO) is universally used as a cryoprotectant in basic and clinical research. Although, the use of DMSO has been under serious debate due to significant clinical side effects correlated with infusions of cellular therapy products containing DMSO, the effect of CP with DMSO on the cell properties and functions remains unknown. Here, we experimentally found that the CP of human bone mesenchymal stem cells (hBMSCs) with 10 % DMSO results 10-15 % of cells apoptosis upon immediate freeze-thaw, ca. 3.8 times of DNA damage/repair relative to the fresh ones after post-thaw cultured in 48 h, and cell cycle arrests at G0/G1 after post-thaw cultured in 24 h. Moreover, CP with 10 % DMSO significantly increases the reactive oxygen species (ROS) level of the frozen-thawed MSCs which may be one of the causes impair cellular properties and functions. Indeed, we found that the differentiation and migration ability of post-thaw cultured hBMSCs decrease as the expression of adipogenic, osteogenic genes and F-actin reduces in the comparison with those of the fresh cells.

The flow behavior and sealing ability of calcium silicate root canal cement containing dimethyl sulfoxide: An in vitro study

INTRODUCTION

To develop a calcium silicate (CaSi)-based cement containing dimethyl sulfoxide (DMSO) and cement deliver device for new root canal filling technique, and to assess the flow behavior, leakage, and root canal filling quality of CaSi containing DMSO.

METHODS

CaSi containing DMSO (CSC-DMSO) and CaSi containing PEG (CSC-PEG) were prepared, and the flow characteristics of both cements were compared in gypsum and resin channels using a high-speed camera. Eight root canals were obturated by CSC-DMSO or CSC-PEG using a cement delivery device, and root canal filling quality was assessed in terms of filling length using periapical radiographs. The filling length was evaluated by 'apico-coronal extension,' measuring length in reference to apical constriction. Microleakage was measured for thirty human molars that were randomly filled with CSC-DMSO, CSC-PEG, or gutta-percha and AH plus. Preliminary obturation of CSC-DMSO with cement delivery device in human teeth was analyzed in terms of filling length and void, using periapical radiographs. Statistical analysis was performed with the Kruskal Wallis test for simulated root canal fillings and one-way ANOVA for leakage test.

RESULTS

The flow speed of CSC-DMSO reduced in gypsum channels compared to resin channels, but CSC-PEG did not exhibit significant differences in the channels. The median absolute value of apico-coronal extension was significantly lower in CSC-DMSO compared to CSC-PEG (p < 0.05). Microleakage did not statistically differ between the groups (p > 0.05). In the preliminary obturation, the mean apico-coronal extension of CSC-DMSO was -0.297 ± 0.724 mm, while CSC-PEG was not feasible due to excess apical extrusions.

CONCLUSIONS

CSC-DMSO could be considered as an alternative filling material for root canal obturation.

A novel sacrificial solvent method to synthesize self-supporting Co9S8/Ni3S2 heterostructure catalyst for efficient oxygen evolution reaction

Synthesizing catalysts for efficient oxygen evolution reaction (OER) with lower cost and simpler design is of significant importance to achieve sustainable hydrogen production. In this work, we propose a novel "sacrificial solvent method" for the first time. Dicobalt octacarbonyl (Co2(CO)8), dimethyl sulfoxide (DMSO), and Ni foam (NF) were used as the raw materials in the solvothermal process. DMSO played the role of both the sacrificial solvent and the sulfur source. Through the self-consumption of DMSO, we finally obtained the Co9S8/Ni3S2 heterostructure supported on the NF (Co9S8/Ni3S2@NF) in one step. The Co9S8/Ni3S2@NF catalyst exhibited excellent OER activity in alkaline environment, with an overpotential of only 264 mV at a current density of 20 mA cm-2, a low Tafel slope of 68.28 mV dec-1 and maintained its current density after 20 h of constant potential testing. This work introduces a new method for synthesizing metal sulfide catalysts using DMSO as a sacrificial solvent. It provides broader opportunities for the development of more efficient and sustainable catalysts for energy conversion and storage.

Influence of microsolvation on vibrational circular dichroism spectra in dimethyl sulfoxide solvent: A Bottom-Up approach using Quantum cluster growth

Chiroptical spectroscopic measurements serve as routine methods to assign the absolute configuration of chiral compounds and interpret their conformational behavior in solution. One common challenge is the use of strongly hydrogen-bonding solvents, which can significantly bias the conformational ensemble and affect the vibrational circular dichroism (VCD) active bands in solution. One such solvent is dimethyl sulfoxide (DMSO)-an excellent solvent for stubborn compounds-that must be explicitly considered in VCD analysis. Explicit consideration of solvent remains a critical challenge in chiroptical spectroscopy due to the need to explore solute-solvent conformational space and the computational expense in modeling these clusters. Interested in the recent development of the Quantum Cluster Growth (QCG) program by the Grimme lab, we set out to model and interpret previously reported VCD spectra for several molecules using their efficient program. Our purposes are two-fold: (1) to investigate the applicability of the QCG program to the problem of reproducing VCD spectra in DMSO solvent and (2) to identify limitations in using this approach. We find that we can conveniently model and analyze the VCD spectra of investigated molecules in DMSO. However, the final set of conformers used for VCD calculations are functional dependent and different sets of conformers can provide satisfactory quantitative agreement between experimental and predicted VCD spectra. We hope that this study provides guidance for future chiroptical studies in the challenging DMSO solvent.

Permeation kinetics of dimethyl sulfoxide in porcine corneoscleral discs

The cornea is the transparent tissue in front of the eye that bends light to help the eye focus. More than five million people's vision can be restored by a corneal transplant (keratoplasty), but there is a scarcity of suitable donor tissue. Cryopreservation could potentially increase the on-demand availability of corneas by reducing expiration and contamination during hypothermic storage, and allow equitable distribution. Understanding the transport of water and cryoprotectants across the tissue is important in developing effective cryopreservation protocols. Here, we first measured the shrinking and swelling kinetics at 22 °C and 0 °C of porcine corneoscleral discs when exposed to phosphate-buffered saline and to a cryoprotectant vehicle solution containing 2.5% chondroitin sulfate and 1% dextran. Other valuable measurements were made including the density and osmolality of the vehicle solution at 0 °C, and the water fraction of porcine cornea and sclera. Using the knowledge gained from this first part to minimize background swelling, we then examined permeation kinetics of dimethyl sulfoxide (Me2SO) in porcine corneoscleral discs at 0 °C, the temperature at which cryoprotectant loading typically occurs. The concentration data obtained as a function of time were fitted to a Fick's law model of one-dimensional diffusion to measure an effective diffusion coefficient of Me2SO, which was found to be 5.306×10-11 m2/s. We further quantified permeation kinetics of Me2SO in sclera alone at 0 °C to support our hypothesis that our measurements for corneoscleral discs will not be affected by the presence of the sclera. The obtained effective diffusion coefficient can be used in modelling aimed at developing cryopreservation protocols that minimize the exposure time of the corneas during the cryoprotectant loading step.

Concentration effect of DMSO-dry bonding on the stability of etch-and-rinse bonds

OBJECTIVES

To examine whether lower dimethyl sulfoxide (DMSO) concentrations would affect long-term bond stability of simplified or multistep water-based adhesives to dry-etched dentin.

METHODS

H3PO4-etched mid-coronal dentin surfaces from human molars were randomly blot- or air-dried for 30 s and pretreated or not with 5 or 50 % (v/v) ethanolic DMSO solutions. Untreated samples served as control. Samples were bonded with a two-step or a three-step etch-and-rinse adhesive. Restored crown segments (n = 5/group) were stored in distilled water for 24 h and sectioned for microtensile bond strength testing. Resin-dentin beams (0.8 mm2) were tested under tension until fracture (0.5 mm/min) after 24 h and one year of storage in artificial saliva at 37 °C. Nanoleakage evaluation and hybrid layer characterization were performed by SEM. Bond strength data was examined by three-way ANOVA followed by the Tukey test (α = 0.05).

RESULTS

Dry bonding produced significantly lower bond strengths than conventional wet bonding for both water-based adhesive systems (p < 0.05). DMSO-dry bonding restored bond strengths and reduced nanoleakage levels, regardless of adhesive type or DMSO concentration (p < 0.05). Bond strengths of DMSO-dry bonded samples were not significantly affected by long-term ageing regardless of adhesive type or DMSO concentration (p < 0.05).

SIGNIFICANCE

Although bonding methacrylate-based resins to etched dentin is normally performed under wet conditions, hybridization of air-dried collagen can outperform conventional wet bonding by employing water-free DMSO solutions with concentrations as low as 5 %. Reduced moisture-related technique sensitivity, higher bonding performance and improved hybrid layer stability may contribute to extend the service life of resin-dentin bonding.

Dimethyl sulfoxide's impact on epileptiform activity in a mouse model of chronic temporal lobe epilepsy

In the quest for novel treatments for patients with drug-resistant seizures, poor water solubility of potential drug candidates is a frequent obstacle. Literature indicated that the highly efficient solvent dimethyl sulfoxide (DMSO) may have a confounding influence in epilepsy research, reporting both pro- and antiepileptic effects. In this study, we aim to clarify the effects of DMSO on epileptiform activity in one of the most frequently studied models of chronic epilepsy, the intrahippocampal kainic acid (IHKA) mouse model, and in a model of acute seizures. We show that 100 % DMSO (in a volume of 1.5 µl/g corresponding to 1651 mg/kg) causes a significant short-term anti-seizure effect in epileptic IHKA mice of both sexes, but does not affect the threshold of acute seizures induced by pentylenetetrazol (PTZ). These findings highlight that the choice of solvent and appropriate vehicle control is crucial to minimize undesirable misleading effects and that drug candidates exclusively soluble in 100 % DMSO need to be modified for better solubility already at initial testing.

Does the application of dimethyl sulfoxide improve resin bonding to eroded dentine? Four-year in vitro evaluation

OBJECTIVE

To evaluate the effect of dimethyl sulfoxide (DMSO) on the microtensile bond strength (µTBS) and nanoleakage (NL) of universal adhesives on eroded dentine, immediately and after four years of water storage.

METHODS

Sixty-four sound human molars were distributed into 16 groups according to (1) Dentine surface (sound and eroded dentine); (2) dimethyl sulfoxide application (with or without); (3) Application mode (etch-and-rinse or self-etch) and (4) Storage time (immediate and four years). One mild universal adhesive was used (Scotchbond Universal). The restoration was then performed with a composite resin and the specimens were sectioned into resin-dentine bonded sticks. Resin-dentine bonded sticks were tested (immediately and after four years of water storage) for µTBS (0.5 mm/min) or used to assess NL. Data on μTBS and NL were analyzed using four-way ANOVA and Tukey's test (α = 0.05).

RESULTS

Only the 3-way cross-product interaction 'substrate vs DMSO vs time' was statistically significant (p = 0.007). Eroded dentine showed a lower mean of µTBS and a higher mean of NL values than sound dentine. However, when DMSO was applied, no significant decrease of μTBS or NL values was observed after four years of water storage, regardless of adhesive strategies, or dentine evaluated, when compared to immediate results.

SIGNIFICANCE

Water-based DMSO pre-treatments not only prevent degradation of MDP-containing simplified adhesives but also serve as a potential alternative to improve long-term bonding properties to eroded dentine. The versatility of using a single pre-treatment for both self-etch or etch-and-rinse bonding to eroded dentin may facilitate future clinical applications.

Carboxymethylcellulose/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate membrane after dimethyl sulfoxide treatment for flexible and high electrochemical performance asymmetric supercapacitors

As the requirements for wearable electronic devices continue to increase, the development of bendable and foldable supercapacitors is becoming critical. However, it is still challenging to design free-standing electrodes with flexibility and high electrical conductivity. Herein, using carboxymethylcellulose (CMC) as the biological template and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) as the electroactive material, a flexible CMC/PEDOT:PSS membrane with a cross-linked mesh structure was firstly synthesized by a facile in-situ polymerization and vacuum filtration process. Subsequently, the CMC/PEDOT:PSS membrane was further treated with dimethyl sulfoxide (DMSO) to remove the excess PSS, thereby enhancing their electrochemical performance. The results showed that the best performing hybrid membrane had good mechanical properties (tensile strength of 48.1 MPa) and high electrical conductivity (45.1 S cm-1). The assembled asymmetric supercapacitor (ASC) is capable of delivering an energy density of 181.9 μW h cm-2 at a power density of 750 μW cm-2 and maintains an initial capacitance of 93.4 % and a coulombic efficiency of 100 % after 10,000 GCD cycles, demonstrating an ultra-long cycle life. Moreover, good electrochemical properties can be retained even in the bent and folded state. Therefore, the hybrid membrane electrode with both flexibility and high electrochemical performance has great potential for application in wearable electronics.

Dimethyl sulfoxide (DMSO): a solvent that may solve selected cutaneous clinical challenges

Dimethyl sulfoxide (DMSO) is a clear, odorless liquid, inexpensively produced as a by-product of the wood pulp industry. DMSO's unique chemical properties allow for its broad applications in a wide variety of cutaneous challenges. Widely available in the USA as a solvent, DMSO is FDA-approved only for the treatment of interstitial cystitis and for use as a preservative for organ transplant. DMSO readily penetrates and diffuses through biological membranes. At low concentrations, DMSO exhibits anti-inflammatory, analgesic, diuretic, vasodilator, anti-platelet aggregation, radio-protective, and muscle-relaxing properties. DMSO is also a vigorous scavenger of hydroxyl free radicals, which may explain its observed beneficial effects on skin rejuvenation and recovery from thermal injury. DMSO has a relatively low level of toxicity. DMSO has shown promise in the off-label treatment of basal cell carcinoma, pressure ulcers, scleroderma, herpes simplex, cutaneous fungal infections, and amyloidosis. The potential of DMSO to serve as an independent or adjuvant topical treatment for these conditions is explored in this review.

Dataset for the experimental study of dimethyl sulfoxide as a thermodynamic inhibitor of methane hydrate formation

To determine the ability of dimethyl sulfoxide (DMSO) to inhibit methane hydrate formation by the thermodynamic mechanism, we measured the pressures and temperatures of monovariant equilibrium of three phases: gaseous methane, aqueous DMSO solution, and methane hydrate. A total of 54 equilibrium points were obtained. Hydrate equilibrium conditions have been measured for eight different concentrations of dimethyl sulfoxide ranging from 0 to 55 mass%, at temperatures of 242-289 K and pressures of 3-13 MPa. Measurements were performed in an isochoric autoclave (volume of 600 cm³, inside diameter of 8.5 cm) at a heating rate of 0.1 K/h and intense fluid agitation (600 rpm) with four-blade impeller (diameter of 6.1 cm, blade height of 2 cm). The specified stirring speed for aqueous DMSO solutions at 273-293 K is equivalent to a range of Reynolds numbers of 5.3‧10³-3.7‧10⁴. The endpoint of methane hydrate dissociation at defined temperature and pressure values was taken as the equilibrium point. The anti-hydrate activity of DMSO was analyzed on a mass% and mol% scale. Precise correlations between the thermodynamic inhibition effect of dimethyl sulfoxide ΔT_h and the influencing factors (DMSO concentration and pressure) were derived. Powder X-ray diffractometry was employed to examine the phase composition of the samples at 153 K. Measurement of ice freezing points in aqueous solutions of dimethyl sulfoxide (up to 50 mass%) at ambient pressure allowed us to clarify the location of the liquidus line in the DMSO-H₂O system and to check the hydrate equilibrium data for thermodynamic consistency.

Improved defluoridation and energy production using dimethyl sulfoxide modified carbon cloth as bioanode in microbial desalination cell

In the present study, carbon cloth (CC) was functionalized using dimethyl sulfoxide (DMSO) and employed as an excellent bioanode for improving defluoridation efficiency, wastewater treatment, and power output from a microbial desalination cell (MDC). The Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis of DMSO modified carbon cloth (CC_DMSO) confirmed the functionalization of CC_DMSO, and the water drop contact angle of 0° ensured its superior hydrophilicity. The presence of -COOH (carboxyl), S[bond, double bond]O (sulfoxide) and O-C[bond, double bond]O (carbonyl) functional groups on CC_DMSO aids in enhancing the performance of the MDC. Besides, cyclic voltametric and electrochemical impedance analysis revealed that CC_DMSO had an excellent electrochemical performance with low charge transfer resistance. Replacing CC with CC_DMSO as anode in MDC, the time required for 3,10 and 20 mg/L of initial fluoride (F^-) concentrations in the middle chamber was reduced from 24 ± 0.75 to 17 ± 0.37, 72 ± 1 to 48 ± 0.70, and 120 ± 0.5 to 96 ± 0.53 h, respectively to meet the prescribed standards (1.5 mg/L). Furthermore, using CC_DMSO, the anode chamber of MDC exhibited a maximum of 83% substrate degradation, and simultaneously, the power output is increased by 2-2.8 times. CC_DMSO improved the power production from 0.009 ± 0.003, 1.394 ± 0.06 and 1.423 ± 0.15 mW/m² to 0.020 ± 0.07, 2.748 ± 0.22 and 3.245 ± 0.16 mW/m², respectively, for initial F^- concentrations of 3,10, and 20 mg/L. Modifying CC with DMSO thus proved to be an efficient and simple methodology for enhancing the overall performance of MDC.

The effect of dentin surface pretreatment using dimethyl sulfoxide on the bond strength of a universal bonding agent to dentin

BACKGROUND

This study aimed to evaluate the effect of dentin pretreatment by Dimethyl Sulfoxide (DMSO) on the bond strength and microleakage of a universal bonding agent to dentin.

METHODS

Fifty-six dentinal discs (thickness = 2 mm) were obtained from the crowns of the human third molars. The disks were assigned into 4 groups and treated as follows; self-etch-control group: G-Premio universal adhesive was used in self-etch mode, total-etch-control: G-Premio universal adhesive was used in total-etch mode, self-etch-DMSO: Water-based DMSO (50% volume) was applied on the samples for 60 s followed by application of G-Premio universal adhesive in self-etch mode, and Total-etch-DMSO: The samples were etched, and then, water-based DMSO was applied on them for 60 s followed by the application of G-Premio universal adhesive in total-etch mode. Afterward, resin composite was placed on all samples and light-cured. The samples were kept in distilled water and subjected to 5000 thermal cycles. Microshear bond strength was measured using the universal testing machine and failure modes were analyzed using a stereomicroscope. Forty-eight human third molars were used for microleakage evaluation and a standardized class five cavity was prepared on the buccal surface of each tooth. The teeth were assigned into 4 groups and received aforementioned surface treatment and the cavities were filled with resin composite. After storing in water for 24 h, the samples were subjected to 5000 cycles of thermocycling and the microleakage level of the samples was evaluated using silver nitrate uptake at the bonded interface. Two-way ANOVA test was used to analyze the effect of bonding technique (self-etch/ total-etch) and DMSO pretreatment on the microshear bond strength and microleakage of G-Premio adhesive to dentin.

RESULTS

Bonding technique had no effect on the bond strength values (p = 0.17) while DMSO pretreatment significantly decreased the microshear bond strength of the samples (p = 0.001). DMSO application increased microleakage significantly in total-etch (P-value = 0.02) while it had no effect in self-etch mode (P-value = 0.44).

CONCLUSIONS

Pretreatment of dentin using 50% DMSO significantly reduced the bond strength of G-Premio Bond in both self-etch and total-etch modes. DMSO effect on microleakage depended on the etching technique; DMSO increased the microleakage level when the adhesive was used in total-etch mode while did not affect the microleakage in self-etch mode.

Surface modification of cellulose with succinic anhydride in dimethyl sulfoxide using potassium carbonate as a catalyst

Cellulose succinates (CSs) having degrees of substitution (DSs) ranging from 0.78 to 2.77 were successfully obtained by reacting cellulose with succinic anhydride (SA) in dimethyl sulfoxide at room temperature using a small amount of inexpensive solid potassium carbonate as a catalyst. Interestingly, CSs with higher DS values were obtained with a much smaller amount of catalyst than previously reported. Moreover, it is possible to control the DS by tailoring the reaction time and mass ratio of cellulose/SA. The hydroxyl groups at the C-6, C-2, and C-3 positions were the main esterification positions. In this process, most of the raw materials are either incorporated into the product or are recoverable. The E-factor, which reflects the sustainability of a given process, was demonstrated to be reduced by 93% by recovering the raw materials.

Prenatal exposure to corn oil, CMC-Na or DMSO affects physical development and multi-organ functions in fetal mice

Corn oil, sodium carboxymethyl cellulose (CMC-Na), and dimethyl sulfoxide (DMSO) are widely used as solvents or suspensions in animal experiments, but the effects of prenatal exposure to them on fetal development have not been reported. In this study, Kunming mice were given a conventional dose of corn oil (9.2g/kg·d), CMC-Na (0.05g/kg·d) or DMSO (0.088g/kg·d) during gestation days 10-18, and the pregnancy outcome, fetal physical development, serum phenotype, and multi-organ function changes were observed. The results showed that corn oil decreased serum triglyceride level in males but increased their serum testosterone and CORT levels, and affected female placenta and female/male multi-organ functions (mainly bone, liver, kidney). CMC-Na increased female/male body lengths and tail lengths, decreased serum glucose and total cholesterol levels in males as well as increased their serum LDL-C/HDL-C ratio and testosterone level, decreased female serum bile acid level, and affected male/female placenta and multi-organ functions (mainly bone, liver, hippocampus). DMSO decreased male body weight and serum glucose level, decreased male/female serum bile acid levels, and affected male/female placenta and multi-organs functions (mainly bone, hippocampus, adrenal gland). In conclusion, prenatal exposure to a conventional dose of corn oil, CMC-Na or DMSO could affect fetal physical development and multi-organ functions, and has the characteristics of "multi-pathway, multi-organ and multi-target". This study provides the experimental basis for the rational selection of solvents or suspensions in pharmacology and toxicology studies. DATA AVAILABILITY: Data will be made available on request.

Solvation role of dimethyl sulfoxide on the interaction with dentin bonding systems after 30 months

OBJECTIVES

To determine whether DMSO could serve as an effective pretreatment to improve the mechanical properties and minimize the degradation of the adhesive interface, through the degree of conversion (DC) and bond strength to dentin of different categories of dentin bonding systems (DBSs) after 30 months.

METHODS

DMSO (0, 0.5, 1, 2, 5, 10 vol%) were incorporated into four categories of DBSs: Adper Scotchbond Multipurpose (MP), Adper Single Bond 2 (SB), Clearfil SE Bond (CSE) and Adper Scotchbond Universal (SU). DC was evaluated by Fourier transform infrared spectroscopy (FTIR). For microtensile bond strength test (µTBS), 1 % DMSO were applied on dentin as pretreatment before DBSs. For SU, both strategies were tested. Specimens for µTBS were tested after 24 h, 6 and 30 months. DC and µTBS data were subjected to two-way ANOVA and Tukey test (α < 0.05).

RESULTS

Incorporating 5 %/10 % DMSO increased the DC of CSE. Controversially, when combined with SU, 2 % and 10 % DMSO jeopardized the DC. Regarding µTBS, 1 % DMSO pre-treatment increased the bond strength for MP, SB, SU-ER and SU-SE. After 30 months, MP, SU-ER and SU-SE showed a decrease compared to baseline but remained higher than the control.

CLINICAL SIGNIFICANCE

DMSO pretreatment may be a useful strategy to improve the bond interface over time. Its incorporation seems to favor the non-solvated systems regarding DC while it seems to show long-term benefits for bond strength using 1 % DMSO for MP and SU systems.

In Situ Fabrication of Lead-Free Double Perovskite/Polymer Composite Films for Optoelectronic Devices and Anticounterfeit Printing

Lead-free double perovskites (DP) have the potential to become a rising star in the next generation of lighting markets by addressing the toxicity and instability issues associated with traditional lead-based perovskites. However, high concentrations of hydrochloric acid (HCl) were often employed as a solvent in the preparation of most DPs, accompanied by slow crystallization at high temperatures, which not only raised the risk and cost in the preparation process, but also had a potential threat to the environment. Here, an in situ fabrication strategy was proposed to realize the crystallization of DP in the polymer at low temperature with a mild dimethyl sulfoxide (DMSO) solvent, and subsequently obtained optically well-behaved Cs₂Na_0.8Ag_0.2BiCl₆/PMMA composite films (CFs) by doping with Ag⁺, generating bright orange luminescence with a photoluminescence quantum yield (PLQY) of up to 21.52%. Moreover, the growth dynamics of Cs₂Na_0.8Ag_0.2BiCl₆/PMMA CFs was further investigated by in situ optical transformation, which was extended to other DP-based polymer CFs. Finally, these CFs exhibited excellent performance in optoelectronic devices and anticounterfeit printing, the results of which provide a new pathway to advance the development of lead-free DP materials in the optical field.

Development of cryopreservation media for the slow-freezing of cultured primordial germ cells in chicken

Conservation of chicken germplasm is crucial in supporting commercial breeds for sustainable egg and meat production and preserving the genetic diversity of indigenous breeds for future breeding. Cryopreservation of chicken fertilized eggs or embryos is not feasible, owing to the large yolk-laden structure of the eggs. Primordial germ cells (PGCs), the embryonic precursors of gametes, are the best candidates for the cryobanking of chicken germplasm. Effective cryobanking of chicken PGCs requires an optimal cryopreservation protocol. Cryomedia containing dimethyl sulfoxide (DMSO) or DMSO combined with serum have been widely used for the cryopreservation of chicken PGCs. However, as cryoprotectants are yet to be optimized for chicken PGCs, the efficacy of cryomedia can be further improved. Here, we investigated the cryoprotective effects of propylene glycol (PG), an alternative to DMSO, on chicken PGCs. We found that the addition of non-permeable cryoprotectants, such as trehalose or chicken serum, to DMSO or PG cryomedia improved the recovery and survival rates of post-thawed PGCs. We further investigated the cryoprotective effects of trehalose and chicken serum and found that these additives have different cryoprotective actions. Based on these findings, we designed two different cryomedia: DTS, including 5% DMSO, 0.3 M trehalose, and 1% chicken serum, and PTS, including 7.5% PG, 0.1 M trehalose, and 5% chicken serum. Among the different PGC lines and freshly isolated PGCs, the cryomedia showed similar post-thaw recovery rates. Following transplantation, post-thawed male PGCs can colonize gonads and differentiate into functional sperm. We successfully revived the offspring of Kurokashiwa, a rare chicken breed in Japan, with cryopreserved PGCs. In conclusion, we developed two different cryomedia that achieved > 50% recovery of viable PGCs after thawing while maintaining germline competency.

Reconsideration of the safety and effectiveness of human oocyte cryopreservation

Mature oocyte cryopreservation (OC) has become increasingly common since the American Society for Reproductive Medicine declared OC to no longer be experimental. Utilization of the open vitrification protocol has led to a marked improvement in the efficacy of oocyte cryopreservation. However, the safety and effectiveness of this cryopreservation method remain controversial. A previous report stated that among all initiated recipient cycles, the live-birth rate among recipients of all ages was significantly higher when using fresh donor oocytes (FDOs) rather than cryopreserved donor oocytes (CDOs). Confounding patient characteristics were noted as possible causes. OC stands as an acceptable elective medical intervention for preserving fertility in women. To further understand the effects of OC on the live birth rate resulting from fresh versus cryopreserved donor oocytes, reported data from the Society for Assisted Reproductive Technology from 2013 to 2020 were analyzed. The mean of the mean live-birth rate in all ages resulting from FDOs was 49.0% (44.6-53.3%) versus 41.0% (39.1-43.2%) for CDOs (difference, 8.0% [95% confidence interval, 5.35-10.57%], p value < 0.001). The lower live-birth rate observed for CDOs versus FDOs has been consistent throughout past decades. While there has been no reported increase in the aneuploidy rate for CDOs compared to FDOs, differences in the nondisjunction separation rate among different chromosomes were described in a recent report. Open vitrification culture medium usually contains high concentrations of cryoprotectants, such as 15% dimethyl sulfoxide (DMSO) and 15% ethylene glycol (EG). Recent studies showed that tissue culture with 0.1% DMSO or 10% EG resulted in deregulation of gene expression, disruption of epigenetic imprints, and accumulation of reactive oxygen species. The addition of melatonin, which can remove reactive oxygen species from vitrification medium, was shown to improve CDOs qualities and functions to conditions similar to those of FDOs; however, there were insufficient data to conclude that melatonin could improve the lower live-birth rate. These factors that affect live birth rates, birth defects, birth weights and developmental health cannot be ignored and perhaps need to be studied again and followed when evaluating the true effectiveness of human oocyte cryopreservation.

Combining environmental, health, and safety features with a conductor like Screening Model for selecting green solvents for antibiotic analyses

Extraction and chromatographic techniques for analyzing pharmaceutically active compounds necessitate large quantities of organic solvents, resulting in a high volume of hazardous waste. The concept of green solvents focuses on protecting the environment by reducing or even eliminating the use of toxic solvents. The main objective of this critical review article is to build a framework for choosing green solvents for antibiotic analyses. The article briefly discusses the chemical properties of ciprofloxacin, sulfamethoxazole, tetracycline, and trimethoprim, and the current state of methodologies for their analyses in water and wastewater. It evaluates the greenness of solvents used for antibiotic analyses and includes insights on the comparison between conventional and green solvents for the analyses. An economic and environmental health and safety analysis combined with a Conductor-like Screening Model for Real Solvent (COSMO-RS) molecular simulation technique for predicting extraction efficiency was used in the evaluation. Methyl acetate and propylene carbonate tied for the greenest solvents from an environmental and economic perspective, whereas the COSMO-RS approach suggests dimethyl sulfoxide (DMSO) as the most suitable candidate. Although DMSO ranked third environmentally and economically, after methyl acetate and propylene carbonate, it would be an ideal replacement of hazardous solvents if it could be manufactured at a lower cost. DMSO showed the highest extraction capacity, as it can interact with antibiotics through hydrophobic interaction and hydrogen bonding. This article can be used as a green solvent selection guide for developing sustainable processes for antibiotic analyses.

Effect of Sustained Systemic Administration of Ginger (Z officinale) Rhizome Extracts on Salivary Flow in Mice

OBJECTIVE

This study aimed to evaluate the effect of methanol (70% v/v), ethanol (80% v/v), dimethyl sulfoxide (DMSO; 100% v/v) extracts of ginger rhizome (GR), and 6-shogaol on the pilocarpine-stimulated salivary flow rate in C57BL/6 mice.

METHODS

Three extracts of ginger (Zingiber officinale) rhizome prepared by maceration using the respective solvents and 6-shogoal were reconstituted in normal saline with 0.2% DMSO. Thirty C57BL/6 15-week-old mice were divided into 5 groups: Group 1, saline; Group 2, 70% methanol extract; Group 3, 80% ethanol extract; Group 4, 100% DMSO extract; and Group 5, 6-shogaol. The baseline pilocarpine-stimulated salivary flow rate was measured at the age of 15 weeks (15th week), and treatment solutions were administered by intraperitoneal injection from the 16th to 18th week. The stimulated salivary flow rate during treatment weeks was recorded for each group, and its difference with baseline was analysed using paired-sample t test. The change in salivary flow rate between the treatment groups and the control group was analysed using one-way analysis of variance.

RESULTS

Groups 2, 3, 4, and 5 showed a significant increase in salivary flow rate when compared to baseline (P < .05). The increase in salivary flow rate in all 4 treatment groups was significant when compared to the control group (P < .05). Group 4 produced the highest increase in salivary flow rate; however, the differences amongst the treatment groups did not reach statistical significance (P > .05).

CONCLUSIONS

All GR extracts (70% methanol, 80% ethanol, 100% DMSO) and 6-shogaol were equally effective in increasing the pilocarpine-stimulated salivary flow rate in C57BL/6 mice when administered systemically as a sustained dose for 3 weeks.

Determination of water content in dimethyl sulfoxide/N,N-dimethyl formamide and methanol content in ethanol by solvatochromism of azo dye, 2-(tert-butyl)-4-methoxy-6-(naphthalen-1-yldiazenyl) phenol

A novel 2-(tert-butyl)-4-methoxy-6-(naphthalen-1-yldiazenyl)phenol (NAP) was synthesized by coupling reaction of 2-tert-butyl-4-methoxyphenol with diazotized naphthylamine as diazo component. The azo dye was characterized by NMR, FT-IR and UV-vis spectroscopic techniques. The visible spectrum of NAP was recorded in different solvents and at different pHs. NAP exhibited a large wavelength shift with increasing solvent polarity, showing significant color change over a wide range in different solvents. The determination of water content in organic solvents miscible with water such as dimethyl sulfoxide (DMSO)/N,N-dimethyl formamide (DMF) and methanol content in ethanol, which is also a common mixture were investigated with NAP which is azo dye. The present reported solvatochromic compound for the determination of water content in DMSO/DMF and methanol content in ethanol showed a fairly wide linear range compared to some previously reported solvatochromic compounds in the literature. In addition, the solvatochromism of NAP allows the determination of methanol content in ethanol, which has caused many deaths, with a fast, cheap and easy method.

Protective effect of nitroglycerin ointment and dimethyl sulfoxide on necrosis of skin flaps in rats

OBJECTIVE

To compare the protective effect of nitroglycerin ointment 2% and Dimethylsulfoxide (DMSO) in dorsal flaps of the rat.

METHODS

A blind, experimental study was conducted in 24 male Wistar rats, with a mean weight of 320 (286-376) grams. Group 1: Control. Petrolatum jelly (Vaseline), n = 8, Group 2: Nitroglycerin (NTG) ointment 2% (Nitro-Bid, Altana Co.) n = 8, and Group 3: DMSO gel 90% (Neogen corp. Lexington KY, 40611), n = 8.

RESULTS

A total of 24 rats were operated on in the 6-month period of this study. Using a non-parametric Mann-Whitney U-test analysis, a statistically significant p was obtained between the control group and 2% NTG ointment, both in the area of necrosis and in the healthy area (p = 0.026). In contrast, the comparison between DMSO [CH3) 2SO] and the control group (p = 0.180) and between both study groups, with a p = 0.18, was not significant.

CONCLUSIONS

Our study concluded that there is a protective effect of 2% NTG ointment for flap survival in relation to the control group (petrolatum). DMSO administered topically did not show a protective effect, compared to the control group.

Effects and mechanisms of decabromodiphenyl ethane on Chlorella sorokiniana: Transcriptomics, proteins and fatty acid production

Decabromodiphenyl ethane is a novel brominated flame retardant, that has always been dissolved in organic solvents to explore its activities on aquatic organisms. In this study, the influences of decabromodiphenyl ethane on the microalga Chlorella sorokiniana (C. sorokiniana) were studied, and three microalgae treatments, including decabromodiphenyl ethane dissolved in dimethyl sulfoxide solvent (DBDPE treatment), dimethyl sulfoxide alone (control II) or untreated (control I) were used in the experiment, respectively. The results showed that the growth of C. sorokiniana was remarkably enhanced in the DBDPE treatment compared with the control I and II groups. Conjoint analysis of transcriptomics and quantitative proteome displayed that the upregulated differentially expressed genes and proteins of DBDPE:control I were enriched in 6 pathways, and downregulated genes/proteins of DBDPE:control I were enriched in 3 pathways. The upregulated differentially expressed genes and proteins of DBDPE:control II were enriched in 4 pathways, and downregulated genes/proteins of DBDPE:control II were enriched in 6 pathways. In addition, decabromodiphenyl ethane changed the fatty acid concentration in C. sorokiniana cells. The activities of superoxide dismutase were enhanced when C. sorokiniana were treated by decabromodiphenyl ethane. The data highlighted that the mRNA and protein expression relating to the fatty acid production, of C. sorokiniana were significantly affected by decabromodiphenyl ethane, and decabromodiphenyl ethane pollution changed the physiological metabolism of microalgae and had harmful effects on natural environments.

Investigation on the role of graphene-based composites for in photocatalytic degradation of phenol-based compounds in wastewater: a review

The ineptitude of conventional water management systems to eradicate noxious compounds leads to the development of advanced treatment systems. The disclosure of graphene-based photocatalytic degradation for the eradication of phenolic compounds has become the "apple of the eye" for many researchers. This review article describes the advanced research progress during the period of 2008-2021 in graphene-based nanocomposites and discusses their different synthesis methods. We will also talk about the applications of nanocomposite in water splitting, dye degradation, solar fuel generations, and organic transformations. Multicomponent heterojunction structure, co-catalyst cohering, and noble metal coupling have been inspected to enhance the photocatalytic performance of graphene-based composite by increasing charge separation and stability. The photocatalytic system's remarkable stability has been described in terms of facile recyclability. The adsorption ability of phenolic compounds has been addressed in the form of Langmuir and Freundlich adsorption isotherm with various factors (pH, concentration, the intensity of light, the effect of catalyst, the effect of time, etc.). The purpose of this review is to survey mechanisms and processes that enlist graphene-based composite in terms of efficacy and dose of catalyst required to attain 99% degradation. Nanoparticles may cause toxicity and a pretext for their toxicity has been mentioned. Finally, it is anticipated that this article could allocate consequential knowledge to fabricating graphene-based composites that are in crucial demand of being discussed in future research.

Injectable redox albumin-based hydrogel with in-situ loaded dihydromyricetin

Albumin is widely used in clinics due to its demonstrated biological safety and functional flexibility. Hydrogels derived from natural albumin possess high moisture retention ability and good biodegradability, making albumin ideal biomaterials compared with synthetic polymers. Herein, by reducing disulfide bonds in bovine serum albumin molecules with glutathione and re-oxidizing the free thiols using dimethyl sulfoxide (DMSO) as additional oxidant, three-dimensional network was assembled, leading to the formation of hydrogel. Meanwhile, DMSO is also an excellent solvent for many drugs, and the hydrophobic drug dihydromyricetin (DMY) can be well dissolved in DMSO. During the crosslinking reaction, DMSO participated in fabricating a porous albumin hydrogel network. At the same time, increased loading of DMY and sustained release of DMY were achieved, improving bioavailability of hydrophobic drug DMY. Rheological test and cytotoxicity assay proved excellent elasticity and biocompatibility of the hydrogel. Self-healing property and narrow-needle injection provided potential application of the hydrogel as biomedical materials. This method for formation hydrogels and in situ loading of drugs may expand to preparing other drug loaded hydrogels and find wide applications.

Self-assembled zein organogels as in situ forming implant drug delivery system and 3D printing ink

Recently, biomedical applications of organogels have been increasing; however, there is a demand for bio-based polymers. Here, we report self-assembled zein organogels in N-methyl pyrrolidone (NMP), Dimethyl sulfoxide (DMSO), and glycerol formal (GF). The gel formation was driven by the solvent's polarity and the hydrogen bonding component of Hansen Solubility Parameters was important in promoting gelation. Gels exhibited shear-thinning and thixotropic properties. Furthermore, water-induced self-assembly of zein allows mechanically robust in situ implant formation by solvent exchange. Ciprofloxacin was incorporated as a model drug and sustained release depending upon the solvent exchange rate was observed. In situ implants in agarose gel retained antibacterial efficacy against S. aureus for more than 14 days. Zein-based organogels were further applied as 3D printing ink and it was found that zein gel in DMSO had superior printability than gels prepared in NMP and GF. Using three solvents to prepare organogels can enable the encapsulation of various drugs and facilitate the preparation of composite gels with other biocompatible polymers. These organogel systems can further be used for developing 3D printed drug delivery systems or scaffolds for tissue engineering.

Temperature-pressure correlations of cryoprotective additives for the design of constant volume cryopreservation protocols

In the recent years, the use of constant volume (isochoric) cryopreservation, in medicine and biotechnology has captured more attention from the research community and now there is an increasing interest in the use of this new technology. It has been established that the thermodynamics of isochoric freezing is different from that of isobaric (constant pressure) freezing. This study provides researchers in the field experimental results for various compositions of cryoprotectants commonly used in isobaric cryopreservation, in terms of temperature-pressure-molar concentration correlation. It also reveals experimental isochoric thermodynamic data for the following cryoprotectants, commonly used in isobaric cryopreservation: dimethyl sulfoxide, trehalose, ethylene glycol and diethylene glycol. Currently, the data on the pressure-temperature correlation in an isochoric system of cryoprotectants used in isobaric cryopreservation is not available. Our new experimental results indicate that the studied concentrations for each of the CPAs, lower and expands the range of temperatures in which cryopreservation by isochoric freezing can be safely practiced. We consider that these experiments will aid researchers developing new isochoric cryopreservation protocols.

Dimethyl sulfoxide and ascarosides improve the growth and yields of entomopathogenic nematodes in liquid cultures

Increasing the infective juvenile (IJ) yields of entomopathogenic nematodes in monoxenic culture systems would reduce their production cost for the market. Ascarosides act as universal nematode pheromones with developmental and behavioral effects of nematodes. Dimethyl sulfoxide (DMSO) is unexpectedly found to enhance the IJ yields of entomopathogenic nematodes on fortified nutrient broth plates. In this study, the influence of selected ascarosides (ascr#7, ascr#9 and ascr#11) and DMSO in three concentrations on the IJ yields of S. carpocapsae All and H. bacteriophora H06 in liquid culture flasks was determined, and the critical development parameters (IJ recovery rate, number of hermaphrodites, number of visible eggs in a hermaphrodite) were examined for H. bacteriophora H06. The results demonstrated that IJ yields were significantly improved in the liquid medium containing 0.01 % DMSO, and 0.02 nM ascr#11 for S. carpocapsae All, and 0.1 % and 0.01 % DMSO and 0.02 pM ascr#11 for H. bacteriophora H06 in proper concentrations. Furthermore, it was discovered that increased recovery rate, hermaphrodite numbers and eggs in the hermaphrodites may contribute to the improved IJ yields of H. bacteriophora H06 in DMSO-supplemented liquid medium. Compared with the control flasks, the IJ yields from the flasks containing 0.01 % DMSO were 15 % and 35 % higher for S. carpocapsae All and H. bacteriophora H06 respectively in 15 days. The cost for ascarosides and DMSO is almost negligible. The results would provide practical technology for low-cost commercial production of these nematodes for pest management program.

The auto-oxidative relithiation of spent cathode materials at low temperature environment for efficient and sustainable regeneration

The reasonable recycling of spent lithium ions batteries is urgently required and beneficial to new energy industry development to approach the "carbon neutral" target. It is urgent to understanding the structural evolution of spent lack lithium cathode materials during direct regeneration technology with low temperatures condition to avoid deficiencies of complex operation in existing technology. Herein, a novel approach was developed for direct regeneration of spent LiCoO₂ materials with a successful structural repair and electrochemical performance recovery, which are composed of auto-oxidative process followed by pre-treatment process of dismantling, soaking and sintering. The auto-oxidative system was composed of LiBr as lithium source and dimethyl sulfoxide as solvent and oxygen donor. The recycled LiCoO₂ material shows significantly close to capacity retention of 90.79% than that of the commercial LiCoO₂ material. Based on the structural evolution mechanism analysis, the novel approach is still expected to be applied into regeneration of other spent cathode materials and guide an efficient and sustainable direction for the recycling of spent lithium ions batteries.

Assessment of larval quality of two bivalve species, Crassostrea angulata and Chamelea gallina, exposed and cryopreserved with different cryoprotectant solutions

Marine bivalves are valuable resources, however, some shellfish populations are endangered due to factors such as anthropogenic pressure, pathologies or lack of reproduction synchrony. Portuguese oyster (Crassostrea angulata) and striped venus clam (Chamelea gallina) have high socio-economic value and their endangered natural populations require rehabilitation. Cryopreservation is a valuable method for the preservation and management of genetic resources for aquaculture and restocking. Larvae cryopreservation is particularly valuable since diploid organisms are obtained upon thawing. The objective of this work was the establishment of C. angulata and C. gallina D-larvae cryopreservation through the selection of permeant cryoprotectant in the freezing solution, namely ethylene glycol (EG) and dimethyl sulfoxide (Me₂SO). Cryoprotectants exposure showed that, in C. angulata, Me₂SO promoted significantly higher incidence of abnormalities and enhanced glutathione reductase activity when compared to control (larvae without cryoprotectant exposure) or even to EG treatment. However, for both species, EG significantly reduced D-larvae average path velocity (VAP). In C. angulata post-thaw D-larvae, EG treatment promoted significantly lower motility and velocity when compared to control and Me₂SO treatment. Superoxide dismutase (SOD) activity showed a reduction in C. angulata post-thaw D-larvae when compared to control, which was compensated by the enhancement of glutathione peroxidase (GPX) activity. In C. gallina post-thaw D-larvae, only motility, velocity and SOD activity were significantly lower than control. Therefore, the best treatment to cryopreserve C. angulata D-larvae was EG while for C. gallina Me₂SO produced better results. This work established for the first time D-larvae cryopreservation protocols for C. angulata and C. gallina.

Cocktail polysaccharides isolated from Ecklonia kurome against the SARS-CoV-2 infection

Previous researches suggested that polysaccharides from brown algae had anti-virus activity. We hypothesized that nature polysaccharide from marine plants might have the effect on anti-SARS-CoV-2 activity. By high throughput screening to target 3CLpro enzyme using polysaccharides library, we discover a crude polysaccharide 375 from seaweed Ecklonia kurome blocked 3CLpro enzymatic activity and shows good anti-SARS-CoV-2 infection activity in cell. Further, we show that homogeneous polysaccharide 37502 from the 375 may bind to 3CLpro well and disturb spike protein binding to ACE2 receptor. The structure characterization uncovers that 37502 is alginate. These results imply that the bioactivities of 375 on SARS-CoV-2 may target multiple key molecules implicated in the virus infection and replication. The above results suggest that 375 may be a potential drug candidate against SARS-CoV-2.

Cryopreservation of C. elegans and Other Nematodes with Dimethyl Sulfoxide and Trehalose

One of the key attributes that has contributed to the popularity of Caenorhabditis elegans as a model system is its ability to survive freezing. By preserving stocks at ultralow temperature, researchers have been able to generate an unlimited number of strains without the burden of constantly maintaining them. This has facilitated the use of large-scale forward genetic screens and CRISPR-mediated genome editing where large numbers of novel and informative mutants can be generated. Traditionally, C. elegans and other nematodes were frozen using glycerol as a cryoprotectant. While effective, a large majority of animals do not survive a typical freeze-thaw cycle. Here I describe an alternative method based on the popular combination of DMSO and trehalose as a cryoprotectant. This method allows the survival of large numbers of worms and effectively protects most developmental stages including adults.

Evaluation of growth, viability, and structural integrity of equine endometrial organoids following cryopreservation

Reproductive diseases in mares are a significant cause of subfertility and profound economic loss in the equine industry. Utilizing a 3D in vitro cell culture system that recapitulates the in vivo physiology will reduce time, cost, and welfare concerns associated with in vivo reproductive research in mares. If this 3D model is combined with effective cryopreservation, reproductive research on mares can occur year-round, which is not currently possible in this seasonal species. Endometrial organoids, 3D in vitro cell clusters that exhibit in vivo uterine physiology, have been established in mice, women, and mares. Here we report the first comprehensive assessment of cryopreservation of endometrial organoids in the domestic mare. Organoid growth rate was not affected by the type of freezing media. However, growth rate varied among non-cryopreserved controls, organoids cryopreserved at passage 0 (P0), and organoids cryopreserved at passage 3 (P3). Additionally, there was no difference in organoid viability among freezing media or freezing timepoint (passages). Furthermore, fresh and frozen-thawed organoids displayed positive immunohistochemical staining for ZO-1, which is a marker for intercellular tight junctions, and for periodic acid-Schiff staining as marker for organoid function through mucin production. Results demonstrate that equine endometrial organoids can be cryopreserved with 10% dimethyl sulfoxide with minimal detrimental effects while maintaining intercellular tight junctions (ZO-1) and secretory function. Availability of cryopreserved endometrial organoids may permit expanded research on uterine pathologies that negatively affect mare fertility and improve efficiency, reduce cost, and minimize animal welfare concerns associated with in vivo research in the domestic mare.

The influence of intermolecular correlations on the infrared spectrum of liquid dimethyl sulfoxide

Dimethyl sulfoxide (DMSO) is routinely applied as an excellent, water-miscible solvent and chemical reagent. Some of the most important data concerning its liquid structure were obtained using infrared (IR) spectroscopy. However, the actual extent of intermolecular correlations that connect the isolated monomer spectrum to the IR response of the bulk liquid is poorly studied thus far. Using ab initio molecular dynamics (AIMD) simulations, IR spectra of liquid DMSO are obtained here from first principles and further analyzed using an array of sophisticated spectral decomposition techniques. The calculated spectra when unfolded in space reveal non-trivial spatial correlations underlying the IR response of liquid DMSO. It is unequivocally demonstrated that some of the fundamental vibrations visible in the intramolecular limit are effectively suppressed by the solvation environment due to symmetry reasons and thus disappear in the bulk limit, escaping experimental detection. Overall, DMSO as an aprotic solvent with dominant dipole-dipole interactions displays strong intermolecular correlations that contribute significantly to the IR spectra, on par with the situation observed in strongly associated liquids, such as water.

Two fungal flavonoid-specific glucosidases/rutinosidases for rutin hydrolysis and rutinoside synthesis under homogeneous and heterogeneous reaction conditions

The glycosidases within GH5-23 cleave the glycosidic bond of β-glucosylated or rutinosylated flavonoids. Moreover, by virtue of their transglycosylation activity, glycoconjugates with glucosyl and rutinosyl moieties are accessible. Here we report the biochemical characterization and biotechnological assessment of two heterologously expressed members of GH5-23—McGlc from Mucor circinelloides and PcGlc from Penicillium chrysogenum. Both enzymes exhibited the highest hydrolytic activities with quercetin-3-β-O-glucopyranoside, whereas lower specificity constants were determined with the rutinosides narcissin, rutin and hesperidin. High stabilities against thermal, ethanol and dimethyl sulfoxide-induced inactivation, a very limited secondary hydrolysis of the formed transglycosylation products, and no detectable product inhibition were additional features appropriate for biotechnological applications. The enzymes were compared in their efficiencies to hydrolyze rutin and to synthesize 2-phenylethyl rutinoside under homogeneous and heterogeneous reaction conditions using high rutin concentrations of 100 and 300 mM. Highest transglycosylation efficiencies were achieved with fully dissolved rutin in reaction mixtures containing 25% dimethyl sulfoxide. Molecular docking and multiple sequence alignments suggest that the hydrophobic environment of aromatic residues within the + 1 subsite of GH5-23 glycosidases is very important for the binding of flavonoid glucosides and rutinosides.

Comparison of diagnosis of cracked tooth using contrast-enhanced CBCT and micro-CT

OBJECTIVES

To evaluate the diagnostic accuracy using sodium iodide (NaI) and dimethyl sulfoxide (DMSO) as contrast agent in cone beam computed tomography (CBCT) scanning, and compare this with micro-CT.

METHODS

18 teeth were cracked artificially by soaking them cyclically in liquid nitrogen and hot water. After pre-treatment with artificial saliva, the teeth were scanned in four modes: CBCT routine scanning without contrast agent (RS); CBCT with meglumine diatrizoate (MD) as contrast agent (ES1); CBCT with NaI + DMSO as contrast agent (ES2); and micro-CT (mCT). The number of crack lines was evaluated in all four modes. Depth of crack lines and number of cracks presented from the occlusal surface to the pulp cavity (Np) in ES2 and micro-CT images were evaluated.

RESULTS

There were 63 crack lines in all 18 teeth. 45 crack lines were visible on ES2 images as against four on the RS and ES1 images (p<0.05) and 37 on micro-CT images (p>0.05). Further, 34 crack lines could be observed on both ES2 and micro-CT images, and the average depth presented on ES2 images was 4.56 ± 0.88 mm and 3.89 ± 1.08 mm on micro-CT images (p<0.05). More crack lines could be detected from the occlusal surface to the pulp cavity on ES2 images than on micro-CT images (22 vs 11).

CONCLUSION

CBCT with NaI +DMSO as the contrast agent was equivalent to micro-CT for number of crack lines and better for depth of crack lines. NaI + DMSO could be a potential CBCT contrast agent to improve diagnostic accuracy for cracked tooth.

Effects of storage media, supplements and cryopreservation methods on quality of stem cells

Despite a vast amount of different methods, protocols and cryoprotective agents (CPA), stem cells are often frozen using standard protocols that have been optimized for use with cell lines, rather than with stem cells. Relatively few comparative studies have been performed to assess the effects of cryopreservation methods on these stem cells. Dimethyl sulfoxide (DMSO) has been a key agent for the development of cryobiology and has been used universally for cryopreservation. However, the use of DMSO has been associated with in vitro and in vivo toxicity and has been shown to affect many cellular processes due to changes in DNA methylation and dysregulation of gene expression. Despite studies showing that DMSO may affect cell characteristics, DMSO remains the CPA of choice, both in a research setting and in the clinics. However, numerous alternatives to DMSO have been shown to hold promise for use as a CPA and include albumin, trehalose, sucrose, ethylene glycol, polyethylene glycol and many more. Here, we will discuss the use, advantages and disadvantages of these CPAs for cryopreservation of different types of stem cells, including hematopoietic stem cells, mesenchymal stromal/stem cells and induced pluripotent stem cells.

Distinct effects of polyphenols and solvents on dentin collagen crosslinking interactions and biostability

OBJECTIVE

To evaluate the effects of different polyphenols and solvents on dentin collagen's crosslinking interactions and biostabilization against MMPs and collagenase degradation.

METHODS

Two polyphenols [proanthocyanidin (PA) and quercetin (QC)] with different water solubility were prepared as treatment solutions using ethanol (EtOH) or dimethyl sulfoxide (DMSO) as solvents. 6-um-thick dentin films were microtomed from dentin slabs of third molars. Following demineralization, films or slabs were subject to 60-s treatment (PA or QC) or no treatment (control) with subsequent extended-rinse with original solvent (EtOH or DMSO) or distilled water (DW). Collagen crosslinking interactions were assessed by FTIR. Biostability was assessed through endogenous MMPs activity via confocal laser scanning microscopy, and exogenous collagenase degradation via weight loss, hydroxyproline release and SEM. Finally, direct collagenase inactivation was also evaluated. Data were analyzed by three-way ANOVA and post-hoc tests (α=0.05%).

RESULTS

Distinct effects of two polyphenols and solvents on collagen crosslinking and biostabilization were observed. Higher crosslinking and biostability efficacy occurred with PA than QC (p<0.001) that demonstrated negligible collagen interactions. With DMSO solvent, efficacy results were significantly reduced with both polyphenols (p<0.05). DMSO-rinse further weakened interactions of PA with collagen, diminishing biostability (p<0.05). Low biostability was detected with QC and DW-rinse, suggesting direct enzymatic inhibition due to physical presence in collagen.

SIGNIFICANCE

Collagen crosslinking interactions and biostability depend on polyphenol chemical characteristics. Treatment-solution solvents may affect interactions between polyphenols and collagen, specifically, DMSO showed detrimental effects on collagen crosslinking and biostability and should be used with caution.

Slow-delivery and distributed exchange of cryoprotective agents with hydrogel beads

Intracellular loading of cryoprotective agents (CPAs) into target cells is a critical step for cryopreservation. However, biological membranes are usually much less permeable to CPAs than to water, resulting in high osmotic pressures and osmotic damage during the CPA loading and unloading phases of cryopreservation. Here, we show that calcium alginate hydrogel beads several millimeters in diamater containing CPAs can be admixed with a cell suspension to spontaneously release CPAs in a gradual and distributed manner. We demonstrate that beads containing cell media enable the gradual removal of CPA from Jurkat cells equilibrated in a typical cryopreservation solution of 15% glycerol, protecting the cells from hypotonic damage. We show that the dynamics of CPA exchange are accurately described by a numerical model of free diffusion within the gel. This approach may enable semiautomated and closed methods of gradual CPA exchange from large volume cell suspensions.

Dry bonding to dentin: Broadening the moisture spectrum and increasing wettability of etch-and-rinse adhesives

OBJECTIVE

To determine whether the effect of dentin moisture on the etch-and-rinse bonding may be minimized by dry-bonding protocols utilizing aqueous or ethanolic dimethyl sulfoxide (DMSO) pretreatments.

METHODS

H₃PO₄-etched mid-coronal dentin surfaces from human molars were randomly blot- or air-dried for 30 s and pretreated with DMSO/H₂O or DMSO/EtOH solutions. Untreated samples served as control. Moisture control was performed by either blot- or air-drying. Samples were bonded with a multistep etch-and-rinse adhesive. Restored crown segments (n = 8/group) were stored in distilled water for 24 h and sectioned for microtensile bond strength testing. Resin-dentin beams (0.8 mm²) were tested under tension until fracture (0.5 mm/min) after 24 h and two years of storage in artificial saliva at 37 °C. SEM nanoleakage evaluation was performed on aged samples. Collagen wettability was also measured by sessile drops of the hydrophilic and hydrophobic bonding resins (n = 8/group). Data were examined by factorial ANOVA followed by the Tukey test (α = 0.05).

RESULTS

Dry bonding to untreated collagen produced inferior immediate and long-term bond strengths than wet bonding (p < 0.05). Regardless of initial hydration and moisture control, DMSO-dry bonding produced initially higher and stable bond strengths after aging (p < 0.05). DMSO-pretreated groups presented improved collagen wettability with lower silver uptake (p < 0.05).

SIGNIFICANCE

Despite the common belief that etch-and-rinse adhesives must be applied onto moist collagen, DMSO-dry bonding protocols not only improved bonding performance and hybrid layer integrity, but also brought more versatility to collagen hybridization by reducing overdrying-related issues.

Thiamine deficiency and recovery: impact of recurrent episodes and beneficial effect of treatment with Trolox and dimethyl sulfoxide

At present, thiamine deficiency (TD) is managed with administration of high doses of thiamine. Even so, severe and permanent neurological disorders can occur in recurrent episodes of TD. In this study, we used a murine model to assess the efficacy of TD recovery treatments using thiamine with or without additional administration of the antioxidant Trolox or the anti-inflammatory dimethyl sulfoxide (DMSO) after a single or recurrent episode of TD. TD was induced for 9 days with deficient chow and pyrithiamine, and the recovery period was 7 days with standard amounts of chow and thiamine, Trolox, and/or DMSO. After these periods, we evaluated behavior, histopathology, and ERK1/2 modulation in the brain. Deficient animals showed reductions in locomotor activity, motor coordination, and spatial memory. Morphologically, after a single episode of TD and recovery, deficient mice showed neuronal vacuolization in the dorsal thalamus and, after two episodes, a reduction in neuronal cell number. These effects were attenuated or reversed by the recovery treatments, mainly in the treatments with thiamine associated with Trolox or DMSO. Deficient animals showed a strong increase in ERK1/2 phosphorylation in the thalamus, hippocampus, and cerebral cortex after one deficiency episode and recovery. Interestingly, after recurrent TD and recovery, ERK1/2 phosphorylation remained high only in the deficient mice treated with thiamine and/or Trolox or thiamine with DMSO. Our data suggest that a protocol for TD treatment with thiamine in conjunction with Trolox or DMSO enhances the recovery of animals and possibly minimizes the late neurological sequelae.

Forced degradation of cell-based medicinal products guided by flow imaging microscopy: Explorative studies with Jurkat cells

Cell-based medicinal products (CBMPs) offer ground-breaking opportunities to treat diseases with limited or no therapeutic options. However, the intrinsic complexity of CBMPs results in great challenges with respect to analytical characterization and stability assessment. In our study, we submitted Jurkat cell suspensions to forced degradation studies mimicking conditions to which CBMPs might be exposed from procurement of cells to administration of the product. Flow imaging microscopy assisted by machine learning was applied for determination of cell viability and concentration, and quantification of debris particles. Additionally, orthogonal cell characterization techniques were used. Thawing of cells at 5 °C was detrimental to cell viability and resulted in high numbers of debris particles, in contrast to thawing at 37 °C or 20 °C which resulted in better stability. After freezing of cell suspensions at -18 °C in presence of dimethyl sulfoxide (DMSO), a DMSO concentration of 2.5% (v/v) showed low stabilizing properties, whereas 5% or 10% was protective. Horizontal shaking of cell suspensions did not affect cell viability, but led to a reduction in cell concentration. Fetal bovine serum (10% [v/v]) protected the cells during shaking. In conclusion, forced degradation studies with application of orthogonal analytical characterization methods allow for CBMP stability assessment and formulation screening.

Dimethyl sulfoxide (DMSO) enhances direct cardiac reprogramming by inhibiting the bromodomain of coactivators CBP/p300

AIMS

Direct cardiac reprogramming represents an attractive way to reversing heart damage caused by myocardial infarction because it removes fibroblasts, while also generating new functional cardiomyocytes. Yet, the main hurdle for bringing this technique to the clinic is the lack of efficacy with current reprogramming protocols. Here, we describe our unexpected discovery that DMSO is capable of significantly augmenting direct cardiac reprogramming in vitro.

METHODS AND RESULTS

Upon induction with cardiac transcription factors- Gata4, Hand2, Mef2c and Tbx5 (GHMT), the treatment of mouse embryonic fibroblasts (MEFs) with 1% DMSO induced ~5 fold increase in Myh6-mCherry+ cells, and significantly upregulated global expression of cardiac genes, including Myh6, Ttn, Nppa, Myh7 and Ryr2. RNA-seq confirmed upregulation of cardiac gene programmes and downregulation of extracellular matrix-related genes. Treatment of TGF-β1, DMSO, or SB431542, and the combination thereof, revealed that DMSO most likely targets a separate but parallel pathway other than TGF-β signalling. Subsequent experiments using small molecule screening revealed that DMSO enhances direct cardiac reprogramming through inhibition of the CBP/p300 bromodomain, and not its acetyltransferase property.

CONCLUSION

In conclusion, our work points to a direct molecular target of DMSO, which can be used for augmenting GHMT-induced direct cardiac reprogramming and possibly other cell fate conversion processes.

Mouse oocyte vitrification with and without dimethyl sulfoxide: influence on cryo-survival, development, and maternal imprinted gene expression

PURPOSE

Oocytes and embryos can be vitrified with and without dimethyl sulfoxide (DMSO). Objectives were to compare no vitrification (No-Vitr), vitrification with DMSO (Vitr + DMSO), and vitrification without DMSO (Vitr - DMSO) on fresh/warmed oocyte survival, induced parthenogenetic activation, parthenogenetic embryo development, and embryonic maternal imprinted gene expression.

METHODS

In this prospective controlled laboratory study, mature B6C3F1 female mouse metaphase II oocytes were treated as: i) No-Vitr, ii) Vitr + DMSO/warmed, and iii) Vitr - DMSO/warmed with subsequent parthenogenetic activation and culture to the blastocyst stage. Oocyte cryo-survival, parthenogenetic activation and embryo development, parthenogenetic embryo maternal imprinted gene expression were outcome measures.

RESULTS

Oocyte cryo-survival was significantly improved in Vitr + DMSO versus Vitr - DMSO at initial warming and 2 h after warming. Induced parthenogenetic activation was similar between all three intervention groups. While early preimplantation parthenogenetic embryo development was similar between control, Vitr + DMSO, Vitr - DMSO oocytes, the development to blastocysts was significantly inferior in the Vitr - DMSO oocytes group compared to the control and Vitr + DMSO oocyte groups. Finally, maternal imprinted gene expression was similar between intervention groups at both the 2-cell and blastocyst parthenogenetic embryo stage.

CONCLUSION(S)

Inclusion of DMSO in oocyte vitrification solutions improved cryo-survival and developmental potential of parthenogenetic embryos to the blastocyst stage without significantly altering maternal imprinted gene expression.

Combined toxicity of dimethyl sulfoxide (DMSO) and vanadium towards zebrafish embryos (Danio rerio): Unexpected synergistic effect by DMSO

Dimethyl sulfoxide (DMSO) is produced in nature and is known to be a source of carbon and sulfur for marine microorganisms. It is currently used in many biological experiments, pharmaceutical preparations, and energy-producing systems such as lithium batteries. Therefore, the toxicity of DMSO has been studied because of its various implications to living organisms; however, such studies are largely limited to measuring individual toxicity whereas the combined toxicity of DMSO with other compounds has rarely been investigated. In the present study, the combined acute toxicity of 0.1% and 0.5% DMSO with vanadium was investigated in zebrafish embryos; the LC₅₀ values of these combinations were 62.0 and 6.38 ppm, respectively. In individual toxicity tests, neither DMSO nor vanadium caused such mortality levels. Therefore, both 0.1% and 0.5% DMSO had a synergistic effect with vanadium, and this result was confirmed using an independent action model. This combined toxicity delayed the development of zebrafish embryos and caused pericardial edema. The synergistic effect of DMSO and vanadium was found to be related to reduced pH and inhibition of cytochrome c oxidase activity. Given its potential synergistic toxicity to aquatic organisms, the introduction of DMSO into the environment should be investigated and routinely monitored.

The pursuit of resin-dentin bond durability: Simultaneous enhancement of collagen structure and polymer network formation in hybrid layers

OBJECTIVE

Imperfect polymer formation as well as collagen's susceptibility to enzymatic degradation increase the vulnerability of hybrid layers over time. This study investigated the effect of new dimethyl sulfoxide (DMSO)-containing pretreatments on long-term bond strength, hybrid layer quality, monomer conversion and collagen structure.

METHODS

H₃PO₄-etched mid-coronal dentin surfaces from extracted human molars (n = 8) were randomly treated with aqueous and ethanolic DMSO solutions or following the ethanol-wet bonding technique. Dentin bonding was performed with a three-step etch-and-rinse adhesive. Resin-dentin beams (0.8 mm²) were stored in artificial saliva at 37 °C for 24 h and 2.5 years, submitted to microtensile bond strength testing at 0.5 mm/min and semi-quantitative SEM nanoleakage analysis (n = 8). Micro-Raman spectroscopy was used to determine the degree of conversion at different depths in the hybrid layer (n = 6). Changes in the apparent modulus of elasticity of demineralized collagen beams measuring 0.5 × 1.7 × 7 mm (n = 10) and loss of dry mass (n = 10) after 30 days were calculated via three-point bending and precision weighing, respectively.

RESULTS

DMSO-containing pretreatments produced higher bond strengths, which did not change significantly over time presenting lower incidence of water-filled zones. Higher uniformity in monomer conversion across the hybrid layer occurred for all pretreatments. DMSO-induced collagen stiffening was reversible in water, but with lower peptide solubilization.

SIGNIFICANCE

Improved polymer formation and higher stability of the collagen-structure can be attributed to DMSO's unique ability to simultaneously modify both biological and resin components within the hybrid layer. Pretreatments composed of DMSO/ethanol may be a viable-effective alternative to extend the longevity of resin-dentin bonds.

Protein-free solution containing trehalose and dextran 40 for cryopreservation of human adipose tissue-derived mesenchymal stromal cells

We tested the efficacy of lactated Ringer's solution with 3% trehalose and 5% dextran 40 (LR-3T-5D) as a vehicle solution for cryopreservation using human adipose-derived mesenchymal stromal cells (hADSCs) with dimethyl sulfoxide (Me2SO). We also tested the effect of the Me2SO concentration in the cryopreservation solution, and the effect of washing with lactated Ringer's solution with 3% trehalose (LR-3T) and replacement with LR-3T or LR-3T-5D. LR-3T-5D was more effective for cell viability, viable cell recovery ratio, annexin V-positive ratio, and colony-forming capacity as a vehicle solution for cryopreservation with 10% Me2SO than LR. The additive effects as cryoprotectants of trehalose and dextran 40 were confirmed to be dose dependent. The cell viability, cell proliferation ability, cell differentiation ability, and the ratio of cell surface positive/negative markers of hADSCs were well maintained after cryopreservation with LR-3T-5D containing 10% Me2SO in liquid nitrogen or in a -80 °C freezer. The cell viability and the proliferation curve in LR-3T-5D with 5% Me2SO were comparable to those with 10% Me2SO. LR-3T-5D was superior to LR-3T as a replacement solution in terms of viability and annexin V positivity. Our data showed that LR-3T-5D is effective as a vehicle solution for cryopreservation. Reducing Me2SO concentration to 5%, and washing and replacement with fresh LR-3T and LR-3T-5D after thawing, are feasible approaches to maintain cryopreservation efficacy.