Cellulose Solution Research Articles

Selülozun TBAF/DMSO Çözücü Sisteminde KH2PO4 ve Na2HPO4 Tuz Karışımı Yerine Transesterifikasyonunda Katalizör Olarak Potasyum Karbonat

Aim of study: This study's goal is to evaluate potassium carbonate as a catalyst for the transesterification of cellulose dissolved in TBAF/DMSO and to identify the optimal reaction conditions. Material and methods: First, a solvent system consisting of 33 g TBAF and 165 g DMSO was prepared for 10 g dissolving pulp in this solvent system for one hour, then the cellulose solution was generated. The catalysts were added to the solution. At reaction temperature, vinyl acetate was added to the solution and the 70-h transesterification process was started. The product was precipitated in ethyl alcohol and washed with water on a sieve, and then dried at room temperature. The effects of changes in catalyst ratio and temperature on bond acetyl groups were investigated by heterogeneous saponification method, FTIR, XRD, DSC, viscosity and solubility test. Main results: The samples' DS values ranged from 1.39 to 2.37 and using phosphate salt mixture catalyst and increasing the ratio of catalyst increased the DS. FTIR and XRD data revealed that acetylation was effective. DSC thermograms showed a minor endotherm at 283.3-291.2°C, and it was identified as the melting point. With potassium carbonate, the viscosity and the solubility of the products increased. Highlights: Cellulose in TBAF/DMSO could be acetylated using potassium carbonate as the catalyst. Potassium carbonate's catalyst activity was weak on DS.

Global characterization of hydrodynamics and gas-liquid mass transfer in a thin-gap bubble column in presence of Newtonian or non-Newtonian liquid phase

Bubble columns are commonly used as photobioreactors (PBRs) due to their good mixing and mass transfer capabilities. Modification in design and operating parameters are nevertheless needed to intensify volumetric productivity. Thin-gap bubble column can be used in this context to operate with high biomass concentration, up to conditions where the culture becomes non-Newtonian. In the present study, the global hydrodynamics and gas–liquid mass transfer inside a 4 mm thickness thin-gap bubble column are characterized in presence of low viscosity Newtonian fluid (water) and two aqueous solutions of Carboxymethyl Cellulose and Xanthan Gum. These shear-thinning solutions are used to mimic high concentration cultures of Chlorella Vulgaris at 42 g.L−1. A range of superficial gas velocities and different capillary diameters are explored to investigate the effect of sparging on hydrodynamics and gas–liquid mass transfer. Studied parameters are flow regimes, mixing, and gas–liquid mass transfer. Results are compared with literature results in classical bubble columns to put into evidence the original effects of both confinement and liquid rheology. Among others, these results show that compared to Newtonian media, non-Newtonian media result in higher gas holdup and mixing times and a lower gas–liquid mass transfer coefficient. The findings suggest that the presence of smaller bubbles would improve mass transfer due to the increased interfacial area, while the presence of larger bubbles would improve mixing performance due to increased vorticity in their wake and relatively greater species transport.

Bacterial cellulose composite hydrogel for pre-concentration and mass spectrometric detection of thiol-containing biomarker

Simple soaking of bacterial cellulose (BC) membrane in carboxymethyl cellulose (CMC) solution yielded BC/CMC hydrogel having re-swellable property. Then, gold nanoparticles (AuNPs) were embedded in the BC/CMC hydrogel via in situ chemical reduction to form BC/CMC/AuNPs composite hydrogel. It was found that the composite hydrogel exhibited physical/chemical characteristics similar to those of BC. The AuNPs with an average diameter of 13 nm distributed uniformly within the BC/CMC matrix as verified by transmission electron microscopy. The novelty of this work is the application of the BC/CMC/AuNPs composite hydrogel for selective adsorption of an important thiol-containing biomarker of Alzheimer's disease, glutathione (GSH), prior to direct laser desorption/ionization mass spectrometric (LDI-MS) detection. GSH adsorbed in the BC/CMC/AuNPs composite hydrogel showed the high ionization signal in LDI-MS providing a linear range of 50–10,000 nM with a limit of detection as low as 54.1 nM, which is a cut-off level for distinguishing between normal individuals and Alzheimer's patients. It should be emphasized that an additional matrix was not necessary as AuNPs can act as self-matrix for LDI-MS analysis. Furthermore, the BC/CMC/AuNPs composite hydrogel can effectively preconcentrate GSH approximately 10 times upon adsorption allowing for ultrasensitive detection of GSH required for disease diagnosis.

Molecularly engineered cellulose hydrogel electrolyte for highly stable zinc ion hybrid capacitors

Zinc ion hybrid capacitors (ZIHCs) are promising candidate for potential large-scale energy storage, but they still suffer from trade-off in energy density and cycling life originated from Zn dendrite growth and side reactions. Herein, we proposed a sustainable molecular engineering strategy of in situ derivatization of cellulose and composition by taking the particular cellulose solution properties in the superbase/DMSO/CO2 solvent system to prepare a carboxylic acid functionalized cellulose (COOH-f-Cell) hydrogel electrolyte capable of regulating Zn electro-deposition behavior. The findings indicated that the solubilization and derivatization of cellulose expanded the inherent inter-/intra hydrogen bonds network, resulting in the formation of unblocking ion channels with grafted carboxylic acid groups. Impressively, carboxylic acid functional groups achieved the homogeneity of the Zn electrodeposition process and induced the formation of a flat stacking layer of (002) crystal planes, thus effectively inhibiting Zn dendrites. Consequently, the cycle stability of the Zn plating/stripping in symmetrical Zn||Zn cell exceeded 5250 h at 0.5 mA cm−2 (over 7.3 months). The ZIHCs delivered a superb cycling life of 70,000 cycles with 91 % capacity retention at 5 A g–1. This strategy proposed here opens up a fresh route for using cellulose hydrogel electrolytes to regulate the deposition behavior of Zn2+ for high-performance zinc-based energy storage systems.

Influence of Crystal Structure on the Set of Physicomechanical Characteristics of Composite Materials Based on Ultra-High Molecular Weight Polyethylene

Composite fibers containing boron(III) have been obtained based on solid solutions of cellulose in N-methylmorpholine-N-oxide and orthoboric acid with their subsequent transformation into a viscous-flow state. The rheological behavior of cellulose solutions with different content of orthoboric acid and water studied under conditions of continuous and dynamic shear loading has confirmed the intermolecular interaction between the components. It has been shown that the mechanical characteristics of the composite fibers obtained from a 16% solution in N-methylmorpholine-N-oxide are comparable to these for hydrated cellulose fibers. The process of transformation of the composite fibers of various compositions into carbon fiber has been investigated by means of thermogravimetric analysis and differential scanning calorimetry. Chemical, structural and morphological properties of composite hydrated cellulose fibers and carbon fibers obtained from them have been studied using FTIR-spectroscopy, X-ray diffraction, and scanning electron microscopy. The influence of boron(III) compounds on the carbonization process and the formation of graphite-like structures in carbon fiber has been investigated by Raman-spectroscopy.

Boron(III)-Containing Composite Hydrated Cellulose Fibers As Precursors of Carbon Materials

Composite fibers containing boron(III) have been obtained based on solid solutions of cellulose in N-methylmorpholine-N-oxide and orthoboric acid with their subsequent transformation into a viscous-flow state. The rheological behavior of cellulose solutions with different content of orthoboric acid and water studied under conditions of continuous and dynamic shear loading has confirmed the intermolecular interaction between the components. It has been shown that the mechanical characteristics of the composite fibers obtained from a 16% solution in N-methylmorpholine-N-oxide are comparable to these for hydrated cellulose fibers. The process of transformation of the composite fibers of various compositions into carbon fiber has been investigated by means of thermogravimetric analysis and differential scanning calorimetry. Chemical, structural and morphological properties of composite hydrated cellulose fibers and carbon fibers obtained from them have been studied using FTIR-spectroscopy, X-ray diffraction, and scanning electron microscopy. The influence of boron(III) compounds on the carbonization process and the formation of graphite-like structures in carbon fiber has been investigated by Raman-spectroscopy.

Direct dissolution of unbleached pulp from corncob and wheat straw in N-methylmorpholine-N-oxide

Lignocellulose, as a kind of abundant natural resource, continuously developed to convert high value-added biological products is of great significance. Herein, we report a N-methylmorpholine-N-oxide (NMMO) solvent system to completely dissolve unbleached pulp to prepare a renewable lignin-containing cellulose film. The viscosity of the completely dissolved cellulose solution was measured using a high-pressure rotary rheometer. The shear viscosity exceeded 85 Pa·s at a shear rate of 1.62 s−1. It exhibited shear-thinning non-Newtonian fluid behavior with increasing shear rate. CF-WS had excellent tensile strength (>73 MPa), and exhibited unique optical properties of high transmittance in the visible region and high shielding performance in the ultraviolet region. When the thickness is only 0.016 mm, the UV shielding rate exceeds 75 % (λ < 380 nm). The structure of the bioplastic was revealed by SEM, XPS, and Raman spectroscopy. Directly dissolving lignocellulose in NMMO aqueous solution is expected to yield bioplastics with high strength and biodegradability. It is a potential substitute for petrochemical plastics and provides a possible way for the utilization of agricultural waste.

Liquid crystallinity of aqueous TEMPO-oxidized hydroxypropyl cellulose solutions: effects of main-chain and side-chain substituents

Liquid crystallinity of aqueous TEMPO-oxidized hydroxypropyl cellulose solutions: effects of main-chain and side-chain substituents

Irreversibility analysis of hydromagnetic viscoelastic Ag-Al2O3/water hybrid nanofluid over a stretching sheet

In many practical applications, magnetic field is applied in modulating underlying flow over a stretching sheet. In the present study, effort has been taken to analyse thermodynamic irreversibility associated with the magnetically actuated flow of viscoelastic fluid over a stretching sheet. The viscoelastic fluid chosen here constitutes aqueous solution of carboxymethyl cellulose containing modest concentration (0.0–0.4%) of Al2O3-Ag nanoparticle. For the description of flow field and thermal transport of energy, the transport equations are solved numerically. Obtained results, primarily focused on parametric variation, are portrayed graphically for different cases pertaining to this analysis. As seen, increasing the magnitude of viscoelastic parameter (K), and Hartmann number (Ha), has significant impact on the flow velocity, convective transport of heat, and consequently, on the thermodynamic irreversibility of the system. Albeit the presence of nanoparticles seems to decrease the flow velocity by yielding more drag to the underlying flow, the same effect on the velocity is found to be insignificant in this analysis, attributed primarily to the accumulation of the nanoparticles in the working fluid.

The effect of hydrogen-rich water on letrozole-induced polycystic ovary syndrome in rats

Research questionWhat is the effect of hydrogen-rich water on rats with polycystic ovary syndrome (PCOS)? DesignFemale rats were divided into four groups, each consisting of eight animals. The control group received a carboxymethyl cellulose (CMC) solution, the molecular hydrogen (H2) group was given hydrogen-rich water and a CMC solution, the PCOS group was administered letrozole dissolved in a CMC solution and the PCOS + H2 group was given hydrogen-rich water and letrozole dissolved in a CMC solution. Blood and tissue samples were then collected, and biochemical and histopathological analyses were conducted on the samples. ResultsThe histopathological analysis showed a reduction in the number of cysts in the PCOS + H2 group compared with the PCOS group (P < 0.0001). Additionally, the malondialdehyde, cortisol and testosterone data revealed a significant decrease in the PCOS + H2 group compared with the PCOS group (P = 0.0458, P = 0.0003, P = 0.0041, respectively). The glutathione also showed a statistically significant increase in the PCOS + H2 group compared with the PCOS group (P = 0.0012). ConclusionThe study findings demonstrate that hydrogen-rich water reduces the number of cysts and oxidative damage in rats with PCOS.

Efficient recycle of waste poly-cotton and preparation of cellulose and polyester fibers using the system of ionic liquid and dimethyl sulfoxide

Efficient recycling of waste textiles is beneficial to the utilization of waste resources and environmental protection. In order to selectively dissolve the cotton from the waste poly-cotton fabrics, 1-allyl-3-methylimidazole chloride ([Amim]Cl)/Dimethyl sulfoxide (DMSO) and 1-ethyl-3-methylimidazolium diethyl phosphate ([Emim]DEP)/DMSO system were used as solvents to dissolve the cotton from the waste poly-cotton fabrics. The influence of dissolved parameters, such as the mass ratio of ionic liquids (ILs) to DMSO, the size and amount of waste poly-cotton fabrics, and the dissolution temperature and time on the dissolution performance were investigated systematically in this work. The results showed that when the mass ratio of [Emim]DEP/DMSO was 5:5, the size of 1.0 × 1.0 cm, the cotton content of 1.4 wt%, the dissolved temperature of 80 °C, and the dissolved time of 60 min, the dissolution rate of cotton from the waste poly-cotton fabrics was 99.9%. The solubilization ability of the [Emim]DEP/DMSO system was higher than that of the [Amim]Cl/DMSO system for cotton, and the viscosity of the obtained cellulose solution was 0.1 Pa·s, which was more favorable for the separation of polyester from the cellulose solution. Furthermore, the degradation of regenerated cellulose obtained in [Emim]DEP/DMSO system was 5.0%, which was much lower than that of the [Amim]Cl/DMSO system. After five recycles, the dissolution rates of each time on cotton were all above 98%, which was basically the consistency with fresh [Emim]DEP/DMSO. In addition, the separated cellulose solution was used to prepare regenerated cellulose fibers by wet spinning, and polyester was used to prepare regenerated polyester fibers by melt spinning, and both of these fibers had smooth and dense surfaces. This strategy may provide a new approach to efficiently recycling waste poly-cotton fabrics.

Pharmacological Evaluation of Ovulation Inducing Potential of Siddha Herbomineral Formulation Arputha Mathirai on Estradiol Valerate Induced Poly Cystic Ovarian Syndrome Wistar Albino Rat Model

Aim: The aim of this study is to examine the potential of Arputha Mathirai, a tablet-based Siddha herbomineral formulation, in promoting ovulation in Wistar Albino rats with polycystic ovary syndrome (PCOS) induced by Estradiol Valerate (EV).&#x0D; Place of Study: The study took place at C.L. Baid Metha College of Pharmacy located in Thorapakkam, Chennai - 600 092, Tamil Nadu.&#x0D; Methodology: Arputha Mathirai, the Siddha herbomineral formulation, was prepared in accordance with Good Manufacturing Practices (GMP) guidelines. Prior to conducting the study, approval was obtained from the Institutional Animal Ethics Committee (IAEC). The research adhered to ethical principles and guidelines established by the committee responsible for overseeing and regulating animal experimentation, ensuring proper control and supervision.&#x0D; Female Wistar Albino rats were selected as the preferred rodent species for the study. Polycystic ovary syndrome (PCOS) was induced in the animals by administering subcutaneous injection of 100μg Estardiol valerate (EV). The reproductive cycles of the rats were synchronized to ensure consistency.&#x0D; The rats were divided into four groups, each containing six rats, as follows:&#x0D; &#x0D; Group I: Normal Control animals received 1 ml/kg of Sodium Carboxymethyl Cellulose (CMC) solution.&#x0D; Group II: Rats were orally administered Arputha Mathirai at a dosage of 100 mg/kg for 10 days.&#x0D; Group III: Rats were orally administered Arputha Mathirai at a dosage of 200 mg/kg for 10 days.&#x0D; Group IV: Received Clomiphene at a dosage of 10 mg/kg and served as the standard group.&#x0D; &#x0D; At the end of the study, blood samples were collected from the rats through retro-orbital and cardiac puncture. The levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, and progesterone were estimated using ELISA method. Ovaries from the experimental rats were dissected out for histopathological studies.&#x0D; Results: The results consistently showed that the higher dosage of the drug (group III) had a more pronounced effect in normalizing hormone levels compared to the lower dosage group. However, it is important to note that the lower dosage group also exhibited effectiveness. While the results in both groups did not closely match those of the standard group (group IV), the drug Arputha Mathirai demonstrated significant potential in the experimental groups, supporting its efficacy in inducing ovulation.&#x0D; Furthermore, the histopathological analysis confirmed the drug's potential in inducing ovulation, particularly in the higher dosage group (group III) compared to the lower dosage group (group II).&#x0D; Overall, the findings suggest that Arputha Mathirai has promising ovulation-inducing activity, with the higher dosage showing more pronounced effects.&#x0D; Conclusion: It is hypothesized that the bioactive phytocompounds present in Arputha Mathirai may exert their effects at various stages to restore hormone levels and reverse the pathological condition associated with PCOS. These natural compounds have the potential to regulate hormone levels and promote ovulation. However, it is important to acknowledge that there is a scarcity of published evidence regarding the specific ability of these phytochemicals to address the underlying causes of the condition. Further research is needed to explore the mechanisms by which these compounds act and their potential in addressing the root causes of PCOS.

Pharmacological Effects of a New Indolinone Derivative in Experimental Pneumonitis in Rats.

We studied the effect of a new indolinone derivative GRS on animal survival and on functioning and histological structure of the lungs in rats with experimental pneumonitis. The rats of experimental groups were intratracheally administered 0.5% aqueous solution of carrageenan under intramuscular anesthesia. Compound GRS (10 mg/kg; a suspension in 0.5% aqueous solution of carboxymethyl cellulose) was orally administered for 4 days starting from the day of carrageenan administration; another rat group received the aqueous solution of carboxymethyl cellulose alone. Control rats received intratracheally isotonic solution of sodium chloride. Animal mortality was registered over 5 days; on day 5, the respiratory parameters were measured, the lungs were weighed, pulmonary edema was evaluated, and histological structure of the lungs was studied. GRS compound improved survival of animals with modeled pneumonitis, restored the respiratory parameters to the level of control animals, and reduced pulmonary edema by 35% and the severity of histological damage score in the lungs by 17% (p<0.05).

Pressure drop and bubble length prediction for gas-non-newtonian fluid two-phase flow in a curved microchannel

The control mechanism of the pressure drop and bubble size has a guiding significance for selecting the micropump, the pressure resistance design, and the precise control of the microfluidics. In this study, single-phase flows and gas-non-Newtonian fluid two-phase flows are studied in a microchannel containing curved structures. Sodium carboxymethyl cellulose solutions are used as the non-Newtonian fluids; water and nitrogen are used as Newtonian fluid and gas phases, respectively. The pressure drop and the bubble length are measured. The influences of operating conditions are discussed. The non-Newtonian properties of the solutions are found to affect the parameters measured significantly. The experimental results are compared with the existing models, and the fanning friction factor is used to evaluate the pressure drop. The two-phase flow pressure drop can be predicted by the Lockhart-Martinelli method with a newly developed C-coefficient as a function of the fluid characteristic parameters and microchannel structure parameters. The new correlation for two-phase pressure drop prediction has an error within 18%, smaller than existing models. A new prediction method for the dimensionless bubble length containing the two-phase friction multiplier is also given with an error of 16%.

Evaluating bubble chain phenomena as a mechanism for open system degassing in basaltic systems

Passive degassing – i.e., the open-system degassing of a magmatic gas phase that is decoupled from the melt phase – is common at many basaltic volcanic systems and consistently makes a greater contribution to total volcanic gas emissions than eruptive degassing. However, the mechanism for passive degassing is not fully understood. We investigate the feasibility of permeable gas flow through connected bubbles or pathways using experiments with aqueous solutions of hydroxyethyl cellulose (HEC), a non-Newtonian analogue material for magma. Stable chains of connected bubbles have previously been reported in similar non-Newtonian polymer solutions. We observe a range of bubble chain phenomena and identified five regimes, numbering in order of increasing gas flow rate: 1) small individual bubbles; 2) chains of rounded bubbles; 3) chains of elongate bubbles; 4) pipe-like ‘winding flue’; 5) large individual bubbles. The bubble chain phenomena (regimes 2–4) are observed over a restricted interval of gas flow rates. We determine the rheology of the solutions and conclude that the HEC solutions that produced bubble chain phenomena in our experiments are well scaled to shear-thinning and viscoelastic magmas, hence bubble chain phenomena could form in magmas. Our analysis also suggests that the viscoelastic rheology of HEC plays a fundamental role in the observed bubble chain phenomena.

Membranes Based on Cellulose and Copolymers of Acrylonitrile Prepared from Joint Solutions.

Cellulose and copolymers of acrylonitrile (PAN) are characterized by their chemical resistance to several conventional solvents. Therefore, these polymers are often used to obtain membranes for the recovery of such solvents. In this work, for the first time, composite membranes formed from highly concentrated mixed solutions based on cellulose and PAN are considered (the total content of polymers is 18 wt.%). For mixed solutions, the morphology and rheological behavior were evaluated. It is shown that the resulting solutions are two-phase, and their morphology depends on the components' ratio and the system's history. The non-monotonous change in the viscosity with the PAN content indicates a specific interaction of cellulose and PAN in N-methylmorpholine-N-oxide solutions. The rheological behavior of mixed solutions allows for their processing in conditions identical to those of cellulose solutions. The introduction of PAN into the cellulose matrix promotes a decrease in the structural order in the system, affecting the membranes' transport properties. For composite membranes, it was found that with an increase in the content of the PAN phase, the retention of Remazol and Orange decreases, while the observed values are several times higher than those for cellulose membranes. The permeability of ethanol increases with increasing terpolymer content.

A hydrophobic/oleophilic silica‐cellulose composite aerogel for oil–water separation

AbstractA cellulose aerogel with very low overall density is fabricated by freeze‐drying aqueous cellulose solution. A hydrophobic/oleophilic cellulose aerogel is further fabricated by coating the cellulose aerogel with hexyltrimethoxysilane‐modified SiO2 nanoparticles. The features of the developed hydrophobic/oleophilic cellulose aerogel are characterized with density and porosity measurement, infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, and contact angle measurement. Finally, the oil absorption performance of the developed hydrophobic/oleophilic cellulose aerogel is investigated. The results show that SiO2 nanoparticles have been successfully loaded on the surface of the aerogel backbone after fulfillment of fabrication, and the surface of the aerogel turns to be hydrophobic/oleophilic (water contact angle 131° and oil contact angle 0°). The oil absorption experiment results show that the absorption capacity for organic solvents is from 10 to 21 times the initial aerogel weight, depending on the density of the absorbed organic solvents. In addition, the aerogel still maintains good stability in high temperature, strong acid or strong base conditions. Furthermore, the aerogel also shows good performance in separating oil from oil–water mixtures. This hydrophobic/oleophilic cellulose aerogel can be a promising choice for remedying water pollution caused by oil contamination.

Effect on the Viscometric Properties of Sodium Carboxymethylcellulose in a Dimethylacetamide and Acetone Mixture

The main objective of our research described here was to determine the viscometric properties of polysaccharide solutions of sodium carboxymethyl cellulose (CMC) in dimethylacetamide (DMA)/acetone (A) mixtures. The evolution of the dynamic and intrinsic viscosities and the effect of the intrinsic Gibbs energy of CMC in DMA/A (44 ml/6 ml) were characterized as a function of the temperature (293.15 to 318.15) K, and concentration (1 to 10) g/l. We identified four main concentration regimes, corresponding to an absorption regime, a dilute regime, a critical regime, and the semi-dilute regime. The thermodynamic parameters of the viscosity also supported the obtained results. Exploiting our results, CMC/DMA/A is a promising solvent mixture for use in pharmaceutical and antibacterial applications.

30-LB: Study on the Mechanism of Calycosin in Promoting Wound Healing in Diabetic Foot Ulcers

Objective: To investigate the effect of calycosin in promoting wound healing of foot ulcers and explore the regulation on vascular endothelial growth factor (VEGF). Methods: 8-week-old male C57BL/6J mice were injected intraperitoneally with 1% streptozotocin 120 mg/kg for 3 consecutive times, and the mice with random blood glucose &amp;gt; 16.7 mmol/L were used and randomly divided into model group and calycosin suspension groups (30 mg/kg, 60 mg/kg, 90 mg/kg). Mice were pretreated for 30 days at a dose of 10 mL/kg of the corresponding drugs once a day, and the control group was given the same dose of 0.5% sodium carboxymethyl cellulose solution. At the end of administration, the animals were anesthetized with isoflurane and the whole layer of skin with diameter 10 mm was removed on the back to establish the wound model of diabetic foot ulcer as day 0. The wound healing was observed and photographed with a camera on the day 0, 2, 4, 6, 8, 10 and 12, respectively. At the end of the day 12, the new tissues around the wound were taken for the detections of the growth of new granulation tissue, VEGF, CD31 and the content of sorbitol. Results: Compared with the model group, the wound healed faster in calycosin groups. It closed on the 12th day, but the wound in the model group did not heal completely. However, there was no obvious dose-effect relationship between different dose groups. The mice in treatment groups showed a better structural integrity of epidermis, and a more expression of VEGF and CD31 in the newborn tissue. And the protein level of VEGF of the calycosin (60 mg/kg) group increased. And the sorbitol content in calycosin (90 mg/kg) group reduced significantly (P&amp;lt;0.05), while in 30 mg/kg and 60 mg/kg changed slightly. Conclusion: Calycosin could promote the wound healing of diabetic foot ulcer, which may be related to the effect of increasing the level of VEGF and reducing the accumulation of sorbitol in tissues. And further research was needed for fully exploration on the mechanism. Disclosure Y. Xu: None. J. Ke: None. L. Yang: None. D. Zhao: None. Funding Tongzhou District Science and Technology Plan Project (KJ2022CX024)

The effects of cystine and theanine mixture on the chronic survival rate and tumor incidence of rats after total body X-ray irradiation†.

Cystine and theanine (CT), an amino acid mixture, provides the substrates cysteine and glutamic acid that promote glutathione synthesis. We previously reported that CT pre-treatment significantly improved the acute survival rate and reduced acute radiation injury of the small intestine and bone marrow of rats after 5Gy of total body X-ray irradiation. To examine the long-term effects of CT administration after irradiation, we investigated the effects of CT pre-treatment and pre- and post-treatment on the chronic survival rate and solid tumor (spleen, skin and subcutis, and thyroid) incidence after irradiation using 7-week-old male Wistar rats. CT pre-treatment of 280mg/kg was administered orally for 5 days before 5Gy irradiation, and CT pre- and post-treatment was administered 5 days before and 5 days after irradiation. A 0.5% carboxymethyl cellulose solution was administered as a control. The chronic survival rate of the pre-treated rats was higher than that of the control rats at 441 days after irradiation (40 vs 8.1%, P = 0.011). However, the survival rate did not significantly differ between the pre- and post-treatment and control rats at 467 days after irradiation (33.8 vs 30.2%, P = 0.792). In addition, more solid tumors, especially subcutis sarcomas, were observed in the pre-treatment rats (26.1%, 6/23) than in the control rats (4.5%, 1/22) after irradiation. Therefore, pre-administration of CT improves the chronic survival rate after irradiation; however, the occurrence of solid tumors was not suppressed.