Novel Studies in the Designs of Natural, Synthetic, and Compound Hydrogels with Biomedical Applications / Novedosos Estudios en el Diseño de Hidrogeles Naturales, Sintéticos y Compuestos con Aplicaciones Biomédicas

ABSTRACT Hydrogels are gaining widespread popularity in the biomedical field due to their extraordinary properties, such as biocompatibility, biodegradability, zero toxicity, easy processing, and similarity to physiological tissue. They have applications in controlled drug release, wound dressing, tissue engineering, and regenerative medicine. Among these applications, hydrogels as a controlled drug delivery system stands out, which releases active substances in precise amounts and at specific times. To explore the latest advances in the design of hydrogels, a literature review of articles published in indexed scientific journals, in Scopus and Science Direct, was carried out. This review aimed to discover and describe the most innovative hydrogel research with applications in the biomedical field; hydrogels synthesized with polymers of different origins were selected, such as; i. Natural (dextran, agarose, chitosan, etc.); ii. Synthetic (polyacrylamide, polyethylene glycol, polyvinyl alcohol, etc.); iii. Composites (interpenetrants, hybrid crosslinkers, nanocomposites, etc.). Comparative analysis revealed that hydrogels with composite materials show the most promise. These composite hydrogels combine the advantages of different polymers or incorporate additional components, offering enhanced properties and functionalities. In summary, hydrogels are versatile biomaterials with immense potential in biomedicine. Their unique properties make them suitable for diverse applications. However, innovative designs and formulations must continue to be explored to further advance the capabilities of hydrogels and expand their biomedical applications.

RESUMEN Los hidrogeles están ganando una extensa popularidad en el campo biomédico gracias a que presentan propiedades extraordinarias como biocompatibilidad, biodegradabilidad, nula toxicidad, fácil procesamiento, y similitud con el tejido fisiológico. tienen aplicaciones en la liberación controlada de fármacos, el vendaje de heridas, la ingeniería de tejidos y la medicina regenerativa. Entre estas aplicaciones, destaca el uso de hidrogeles como sistema de administración controlada de fármacos, que liberan sustancias activas en cantidades precisas y en momentos concretos. Para explorar los últimos avances en el diseño de hidrogeles, se realizó una revisión bibliográfica de artículos publicados en revistas científicas indexadas, en Scopus y Science Direct. El objetivo de esta revisión fue descubrir y describir las investigaciones de hidrogeles más innovadoras con aplicaciones en el campo biomédico, se seleccionaron hidrogeles sintetizados con polímeros de diferente índole como; i. Naturales (dextrano, agarosa, quitosano, etc.); ii. Sintéticos (poliacrilamida, polietilenglicol, alcohol polivinílico, etc); iii. Compuestos (interpenetrantes, reticulantes híbridos, nanocompuestos, etc.). El análisis comparativo reveló que los hidrogeles que utilizan materiales compuestos son los más prometedores. Estos hidrogeles compuestos combinan las ventajas de distintos polímeros o incorporan componentes adicionales, ofreciendo propiedades y funcionalidades mejoradas. En resumen, los hidrogeles son biomateriales versátiles con un inmenso potencial en biomedicina. Sus propiedades únicas los hacen adecuados para diversas aplicaciones, sin embargo, se debe seguir explorando diseños y formulaciones innovadores para seguir avanzando en las capacidades de los hidrogeles y ampliar sus aplicaciones biomédicas.

Research progress in microenvironmentally responsive hydrogel materials for chronic refractory wounds / 国际生物医学工程杂志

Chronic refractory wounds have been a challenge for clinical treatment because of their diverse causative factors and complex pathological processes, long healing times, and high treatment costs. The microenvironment of the wound surface includes the external microenvironment of the periwound surface, the internal microenvironment of the wound surface, and subsurface physiological structures. Research on clinical treatment strategies based on the microenvironment of chronic refractory wounds continues to innovate and make progress. Hydrogels have the advantages of high-water content, adjustable performance, good biocompatibility, and similarity to extracellular matrix. The ability of hydrogels to load drugs and their modification to confer excellent tissue adhesion, antibacterial, antioxidant, and modulation of inflammatory factor expression can be used to achieve a multi-factor response and modulation of the physical, chemical, and biological aspects of the trauma microenvironment. Therefore, hydrogels have outstanding advantages and clinical application prospects in the repair of chronic, difficult-to-heal wounds. In this review paper, the characteristics and etiology of chronic refractory wounds were introduced, and the classification of microenvironment-responsive hydrogels for chronic refractory wounds and their application in the repair of refractory wounds were reviewed. Besides, the shortcomings of current hydrogels were discussed, and an outlook was proposed.

Research progress of the application of peptide hydrogel in the revascularization of pulp regeneration / 国际生物医学工程杂志

In recent years, problems such as the devitalization of dental pulp and the increased brittleness and fragility of teeth after root canal treatment have attracted more and more attention. Therefore, pulp regeneration has become the focus of research in endodontics and periapical disease, in which vascularization is of paramount importance. It is found that peptide hydrogel scaffolds have been widely applied because of their properties of impacting cell behavior, promoting angiogenesis, and being adaptable. In this review paper, the research progress of the application of peptide hydrogel in the vascularization of pulp regeneration and the properties of various peptide hydrogels were summarized to provide a reference for the further application of peptide hydrogel in pulp regeneration.

Preparation and performance evaluation on chitosan/gelatin hydrogel hemostatic material containing Panax notoginseng / 国际生物医学工程杂志

Objective:To prepare chitosan/gelatin hydrogel composite hemostatic materials loaded with Panax notoginseng (PN/CMC/GMs) and evaluate their performance. Methods:PN/CMC/GMs hydrogel composite hemostatic material were prepared by the freeze-drying method, and their morphology was observed by scanning electron microscopy. Their rheological properties were observed by a rheometer. Their water absorption rate was tested by dissolution. Their biocompatibility was detected by a cytotoxicity assay. Their rapid hemostatic effect was tested using a SD rat liver hemorrhage model.Results:PN/CMC/GMs composite hemostatic materials were prepared in a lattice-like structure with certain porosity. With the increase in Panax notoginseng powder content, the modulus of PN/CMC/GMs increased accordingly, and the mechanical strength increased. PN/CMC/GMs have better water absorption and expansion functions, which can form compression hemostasis and concentrated blood to achieve rapid hemostasis, and have good biocompatibility. Hemostasis experiments showed that the hemostatic time and hemostatic effect of PN, CMC/GMs hemostatic materials on liver injury in rats were better than those of the blank control group. Conclusions:PN/CMC/GMs have good hemostatic effect and biocompatibility and have the potential for further research and clinical application.

Application of hydrogel-loaded stem cell exosomes in the field of tissue regeneration / 生物工程学报

In recent years, mesenchymal stem cell (MSCs)-derived exosomes have attracted much attention in the field of tissue regeneration. Mesenchymal stem cell-derived exosomes are signaling molecules for communication among cells. They are characterized by natural targeting and low immunogenicity, and are mostly absorbed by cells through the paracrine pathway of mesenchymal stem cells. Moreover, they participate in the regulation and promotion of cell or tissue regeneration. As a scaffold material in regenerative medicine, hydrogel has good biocompatibility and degradability. Combining the two compounds can not only improve the retention time of exosomes at the lesion site, but also improve the dose of exosomes reaching the lesion site by in situ injection, and the therapeutic effect in the lesion area is significant and continuous. This paper summarizes the research results of the interaction of exocrine and hydrogel composite materials to promote tissue repair and regeneration, in order to facilitate research in the field of tissue regeneration in the future.

Bone-derived MSCs encapsulated in alginate hydrogel prevent collagen-induced arthritis in mice through the activation of adenosine A2A/2B receptors in tolerogenic dendritic cells

Tolerogenic dendritic cells (tolDCs) facilitate the suppression of autoimmune responses by differentiating regulatory T cells (Treg). The dysfunction of immunotolerance results in the development of autoimmune diseases, such as rheumatoid arthritis (RA). As multipotent progenitor cells, mesenchymal stem cells (MSCs), can regulate dendritic cells (DCs) to restore their immunosuppressive function and prevent disease development. However, the underlying mechanisms of MSCs in regulating DCs still need to be better defined. Simultaneously, the delivery system for MSCs also influences their function. Herein, MSCs are encapsulated in alginate hydrogel to improve cell survival and retention in situ, maximizing efficacy in vivo. The three-dimensional co-culture of encapsulated MSCs with DCs demonstrates that MSCs can inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines. In the collagen-induced arthritis (CIA) mice model, alginate hydrogel encapsulated MSCs induce a significantly higher expression of CD39+CD73+ on MSCs. These enzymes hydrolyze ATP to adenosine and activate A2A/2B receptors on immature DCs, further promoting the phenotypic transformation of DCs to tolDCs and regulating naïve T cells to Tregs. Therefore, encapsulated MSCs obviously alleviate the inflammatory response and prevent CIA progression. This finding clarifies the mechanism of MSCs-DCs crosstalk in eliciting the immunosuppression effect and provides insights into hydrogel-promoted stem cell therapy for autoimmune diseases.

Preparation of silk fibroin/hyaluronic acid composite hydrogel based on thiol-ene click chemistry / 浙江大学学报·医学版

OBJECTIVES@#To design and prepare silk fibroin/hyaluronic acid composite hydrogel.@*METHODS@#The thiol modified silk fibroin and the double-bond modified hyaluronic acid were rapidly cured into gels through thiol-ene click polymerization under ultraviolet light condition. The grafting rate of modified silk fibroin and hyaluronic acid was characterized by 1H NMR spectroscopy; the gel point and the internal microstructure of hydrogels were characterized by rheological test and scanning electron microscopy; the mechanical properties were characterized by compression test; the swelling rate and degradation rate were determined by mass method. The hydrogel was co-cultured with the cells, the cytotoxicity was measured by the lactate dehydrogenase method, the cell adhesion was measured by the float count method, and the cell growth and differentiation on the surface of the gel were observed by scanning electron microscope and fluorescence microscope.@*RESULTS@#The functional group substitution degrees of modified silk fibroin and hyaluronic acid were 17.99% and 48.03%, respectively. The prepared silk fibroin/hyaluronic acid composite hydrogel had a gel point of 40-60 s and had a porous structure inside the gel. The compressive strength was as high as 450 kPa and it would not break after ten cycles. The water absorption capacity of the composite hydrogel was 4-10 times of its own weight. Degradation experiments showed that the hydrogel was biodegradable, and the degradation rate reached 28%-42% after 35 d. The cell biology experiments showed that the cytotoxicity of the composite gel was low, the cell adhesion was good, and the growth and differentiation of the cells on the surface of the gel were good.@*CONCLUSIONS@#The photocurable silk fibroin/hyaluronic acid composite hydrogel can form a gel quickly, and has excellent mechanical properties, adjustable swelling rate and degradation degree, good biocompatibility, so it has promising application prospects in biomedicine.

Applicatoin of chitosan-based hydrogel in oral tissue engineering / 中南大学学报(医学版)

Pulpitis, periodontitis, jaw bone defect, and temporomandibular joint damage are common oral and maxillofacial diseases in clinic, but traditional treatments are unable to restore the structure and function of the injured tissues. Due to their good biocompatibility, biodegradability, antioxidant effect, anti-inflammatory activity, and broad-spectrum antimicrobial property, chitosan-based hydrogels have shown broad applicable prospects in the field of oral tissue engineering. Quaternization, carboxymethylation, and sulfonation are common chemical modification strategies to improve the physicochemical properties and biological functions of chitosan-based hydrogels, while the construction of hydrogel composite systems via carrying porous microspheres or nanoparticles can achieve local sequential delivery of diverse drugs or bioactive factors, laying a solid foundation for the well-organized regeneration of defective tissues. Chemical cross-linking is commonly employed to fabricate irreversible permanent chitosan gels, and physical cross-linking enables the formation of reversible gel networks. Representing suitable scaffold biomaterials, several chitosan-based hydrogels transplanted with stem cells, growth factors or exosomes have been used in an attempt to regenerate oral soft and hard tissues. Currently, remarkable advances have been made in promoting the regeneration of pulp-dentin complex, cementum-periodontium-alveolar bone complex, jaw bone, and cartilage. However, the clinical translation of chitosan-based hydrogels still encounters multiple challenges. In future, more in vivo clinical exploration under the conditions of oral complex microenvironments should be performed, and the combined application of chitosan-based hydrogels and a variety of bioactive factors, biomaterials, and state-of-the-art biotechnologies can be pursued in order to realize multifaceted complete regeneration of oral tissue.

Cell-loaded hydrogel microspheres based on droplet microfluidics: a review / 生物工程学报

Droplet microfluidics technology offers refined control over the flows of multiple fluids in micro/nano-scale, enabling fabrication of micro/nano-droplets with precisely adjustable structures and compositions in a high-throughput manner. With the combination of proper hydrogel materials and preparation methods, single or multiple cells can be efficiently encapsulated into hydrogels to produce cell-loaded hydrogel microspheres. The cell-loaded hydrogel microspheres can provide a three-dimensional, relatively independent and controllable microenvironment for cell proliferation and differentiation, which is of great value for three-dimensional cell culture, tissue engineering and regenerative medicine, stem cell research, single cell study and many other biological science fields. In this review, the preparation methods of cell-loaded hydrogel microspheres based on droplet microfluidics and its applications in biomedical field are summarized and future prospects are proposed.

Association of Rhizophora mangle and ascorbic acid in hydrogels: Evaluation of cytotoxic and immunomodulatory effects

Abstract Polyphenolics from Rhizophora mangle (R. mangle) have shown wound healing and anti- inflammatory effects that may be potentiated by being associated with ascorbic acid, an important substance for collagen and elastin synthesis that plays a role in tissue repair. In our study, we aimed to formulate an association of R. mangle and ascorbic acid in hydrogels and evaluate the association's cytotoxic and immunomodulatory effects. In a pre-formulation study, three gelling polymers (i.e.xanthan gum, poloxamer and hydroxyethyl cellulose) were tested. The selected polymer (i.e. xanthan gum) was used to evaluate cytotoxic and immunomodulatory effects using flow cytometry. Xanthan gum (1.5%) had a homogeneous appearance, an orange colour, a smooth surface, intense brightness and the typical odour, as well as non-Newtonian pseudoplastic behaviour. With a pH of 5.0-5.3 and a non-cytotoxic profile, xanthan gum induced the proliferation and activation of CD4 +, CD8+ and NK T lymphocytes and the production of IL- 2, IL-4, IL-10, IL-17 and TNF-α cytokines in stimulated splenocytes. The results suggest that the association of R. mangle and ascorbic acid in 1.5% xanthan gum hydrogel may be promising in preparations for wound-healing processes.

Esferas de hidrogel relacionadas con oclusión intestinal / Bowel obstruction related to hydrogel beads

Resumen Introducción: La obstrucción intestinal por ingesta accidental de cuerpos extraños se presenta muy rara vez en la edad pediátrica debido a que del 80 al 90% de los objetos pueden pasar libremente por el tracto gastrointestinal. Caso clínico: Se aborda el caso de una paciente de sexo femenino de 1 año 2 meses quien presentó obstrucción intestinal debido a la ingesta de esferas de hidrogel (poliacrilato de sodio). Dichas esferas, que son utilizadas como juguetes didácticos o sensoriales, aumentan de 200 a 400 veces su tamaño inicial mediante la absorción de agua. Se realizó radiografía abdominal en proyección decúbito supino, donde llamó la atención el hallazgo de defecto de llenado redondeado en asa de flanco derecho, ya que las esferas de hidrogel son radiolúcidas. El diagnóstico se estableció mediante ultrasonido abdominal, donde se reportó líquido libre peritoneal con datos de suboclusión por cuerpos extraños a nivel intestinal. Se indicó tratamiento conservador, encontrando persistencia de aumento de perímetro abdominal. Se realizó enterotomía y se encontraron las esferas impactadas a 30 centímetros de la válvula ileocecal. Conclusiones: Las esferas de hidrogel son peligrosas para la población pediátrica. La evolución de la paciente fue favorable debido al conocimiento del objeto extraño ingerido. Sobresale la conducta expectante que se tuvo que desempeñar debido a que se desconocía el crecimiento de las esferas y en qué momento no podrían continuar su paso por el tracto gastrointestinal.

Abstract Background: Bowel obstruction due to accidental ingestion of foreign objects occurs rarely in children because 80 to 90% of the objects can pass freely through the gastrointestinal tract. Case report: We report a case of a 14-month-old infant who presented bowel obstruction caused by the ingestion of hydrogel beads (sodium polyacrylate). Hydrogel beads are used as sensory and didactic toys that can increase their initial size 200 to 400 times by liquid absorption. An abdominal X-ray was perfomed in anteroposterior supine projection, where a round filling defect at the loop of the right flank was detected; this came to our attention because hydrogel beads are usually radiolucent. The diagnosis was established by abdominal ultrasound where free intraperitoneal fluid was reported with data of small bowel pseudo-obstruction by foreign objects. Conservative treatment was prescribed, finding persistence of increased abdominal perimeter, so an enterotomy was performed for their removal; finding impacted hydrogel beads 30 centimeters from the ileocecal valve. Conclusions: Hydrogel beads are dangerous for the pediatric population. The evolution of the patient was favorable thanks to the knowledge of the foreign objects ingested. The expectant behavior that had to be executed, stands out because we had no knowledge as to the maximum size of the hydrogel in the gastrointestinal tract.

The use of integrin binding domain loaded hydrogel (RGD) with minimally invasive surgical technique in treatment of periodontal intrabony defect: a randomized clinical and biochemical study

Abstract Periodontal regeneration faces multiple challenges, the most important being cellular insufficiency. In an attempt to improve defect cellularity, we aimed to demonstrate enhancing cellular attraction using arginine-glycine-aspartic acid (RGD) adhesion molecule legend blended hydrogel within the intrabony defects. Methodology Forty-five intrabony defects were selected from patients with stage III or IV - grade A or B periodontitis and divided randomly into three equal groups of 15 each: group1 (G1): received minimally invasive surgical technique (MIST) alone, group2 (G2): received MIST and placebo hydrogel injection, and group3 (G3): were treated with MIST and RGD hydrogel injection. Primary outcomes 6 months following therapy were; defect base fill (DBF) and defect width measurement (DW); secondary outcomes were clinical attachment level (CAL), pocket depth (PD), plaque index (PI), gingival index (GI), and biochemical analysis of bone morphogenetic protein (BMP-2) evaluated at 1,7,14 and 21 days following therapy. Results Significant improvements in DBF, CAL, and PD were observed in the three studied groups 6 months following therapy compared to baseline (p<0.05). A significant improvement in DBF was reported in G3 compared to G1 and 2 (p=0.005). Additionally, a significantly higher CAL gain was reported in G3 compared to that of G1 (p=0.02). Group 3 was associated with a significantly higher level of BMP-2 compared to G1 and G2 in all reported periods. Conclusion RGD peptide carried on a hydrogel delivery agent and contained with a minimally invasive flap could be a reliable option in improving the outcomes of periodontal therapy.

Development and clinical application of hydrogel formulations containing papain and urea for wound healing

Abstract Hydrogels are used for wound treatment, as they may contain one or more active components and protect the wound bed. Papain is one of the active substances that have been used with this purpose, alongside urea. In this paper, carboxypolymethylene hydrogels containing papain (2% and 10% concentrations) and urea (5% concentration) were produced. Physical-chemical stability was performed at 0, 7, 15 and 30 days at 2-8ºC, 25ºC and 40ºC, as well as the rheological aspects and proteolytic activity of papain by gel electrophoresis. Clinical efficacy of the formulations in patients with lower limb ulcers was also evaluated in a prospective, single-center, randomized, double-blind and comparative clinical trial. The results showed 7-day stability for the formulations under 25ºC, in addition to approximately 100% and 15% of protein activity for 10% and 2% papain hydrogel, respectively. The rheological profile was non-Newtonian for the 10% papain hydrogel tested. There were no significant differences regarding the mean time for healing of the lesions, although 10% papain presented a better approach to be used in all types of tissue present in the wound bed.

Evaluation of superabsorbent polymer (SAP) in oviposition traps used in the integrated control of Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1894) (Diptera:Culicidae)

ABSTRACT Background: Egg collection traps have been studied to assist in the integrated control of arbovirus vectors. Many enhancements have been made over the years. Methods: This study evaluated the use of a hydrated superabsorbent polymer (SAP) in the egg collection of Aedes aegypti and Aedes albopictus in ovitraps. An experiment was conducted in the laboratory to determine the minimum concentration of the product to be used in traps in the field to prevent the development of larvae into adults. In the field, the use of polymers has been evaluated using a traditional model of ovitraps. The positive ovitrap index and mean number of eggs per trap indicator were calculated. Results: In the laboratory, the larvae did not successfully develop to the adult stage, even at the lowest SAP concentration. In the field, the results showed that ovitraps with SAP proved to be effective for egg collection from both species. It was possible to identify sites with the highest concentration of species and expose the ovitraps for a longer period without larval development. Conclusions: There is a need for studies on the adequacy of this technology for control programs. However, the results showed that ovitraps with hydrogel were potentiated to capture eggs, configuring themselves as another tool for vector control.

Pro-angiogenic photo-crosslinked silk fibroin hydrogel: a potential candidate for repairing alveolar bone defects

Abstract Objective: This study aimed to develop a pro-angiogenic hydrogel with in situ gelation ability for alveolar bone defects repair. Methodology: Silk fibroin was chemically modified by Glycidyl Methacrylate (GMA), which was evaluated by proton nuclear magnetic resonance (1H-NMR). Then, the photo-crosslinking ability of the modified silk fibroin was assessed. Scratch and transwell-based migration assays were conducted to investigate the effect of the photo-crosslinked silk fibroin hydrogel on the migration of human umbilical vein endothelial cells (HUVECs). In vitro angiogenesis was conducted to examine whether the photo-crosslinked silk fibroin hydrogel would affect the tube formation ability of HUVECs. Finally, subcutaneous implantation experiments were conducted to further examine the pro-angiogenic ability of the photo-crosslinked silk fibroin hydrogel, in which the CD31 and α-smooth muscle actin (α-SMA) were stained to assess neovascularization. The tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were also stained to evaluate inflammatory responses after implantation. Results: GMA successfully modified the silk fibroin, which we verified by our 1H-NMR and in vitro photo-crosslinking experiment. Scratch and transwell-based migration assays proved that the photo-crosslinked silk fibroin hydrogel promoted HUVEC migration. The hydrogel also enhanced the tube formation of HUVECs in similar rates to Matrigel®. After subcutaneous implantation in rats for one week, the hydrogel enhanced neovascularization without triggering inflammatory responses. Conclusion: This study found that photo-crosslinked silk fibroin hydrogel showed pro-angiogenic and inflammation inhibitory abilities. Its photo-crosslinking ability makes it suitable for matching irregular alveolar bone defects. Thus, the photo-crosslinkable silk fibroin-derived hydrogel is a potential candidate for constructing scaffolds for alveolar bone regeneration.

Improvement effects of Shangke xiaoyan hydrogel plaster on osteoarthritis model rats / 中国药房

OBJECTIVE To study the improvement effects of Shangke xiaoyan hydrogel plaster on osteoarthritis （OA） model rats. METHODS Rats were randomly divided into blank group， model group， voltaren group （200 mg/rat）， Shangke xiaoyan ointment group （500 mg/rat， containing Shangke xiaoyan fluid extract 50 mg） and Shangke xiaoyan hydrogel plaster group （200 mg/rat， containing Shangke xiaoyan fluid extract 50 mg）， with 8 rats in each group. Except for blank group， OA model was established in the other groups by injecting papain and L-cysteine into the right knee joint cavity of the rats； they applied the corresponding drugs， and changed the dressing once a day， for 14 consecutive days. The degree of knee joint swelling in rats was detected， and the magnetic resonance imaging characteristics of the knee joint in rats were observed； the levels of interleukin 1β （IL-1β）， IL-6， IL-18 and tumor necrosis factor （TNF- α） in rat serum were detected； the pathological and morphological characteristics of knee joint tissue were observed， and the histopathological and cartilage Mankin scores were performed； the protein expressions of IL-1β， IL-6 and TNF-α in knee joint tissue were all detected. RESULTS Compared with blank group， severe joint swelling， obvious joint effusion and patchy wear of the anterior horn of the lateral meniscus were observed in model group； the serum levels of IL-1β， IL-6， IL-18 and TNF- α and histopathological score and Mankin score were significantly increased （P＜0.05）； protein expressions of IL-1β， IL-6 and TNF-α in knee joint tissue were increased. Compared with model group， the knee swelling degree of the rats in Shangke xiaoyan hydrogel plaster group was reduced， a small amount 　　 of joint cavity effusion could be seen， and the shape of the meniscus was completely normal； the histopathological score E-mail：frankyan@cpu.edu.cn and Mankin score were significantly reduced （P＜0.05）levels of inflammatory factors in serum were reduced （P＜0.05） and those of knee tissue were decreased. CONCLUSIONS Shangke xiaoyan hydrogel plaster can improve OA of rats， the mechanism of which may be associated with reducing the levels of inflammatory factors in joint and serum.

A case report of Scleral Buckle implant mimicking an orbital tumor

Objective@#We report a case of a scleral buckle mimicking an orbital tumor 28 years after a retinal detachment repair.@*Methods@#This is a case report.@*Results@#A 75-year-old male consulted for progressive, painless blurred vision of the right eye. He had a history of scleral buckling surgery for retinal detachment on the right eye in 1990 that restored his vision. Examination showed right eye ophthalmoplegia and inferior displacement of the globe. Imaging revealed a right supero-temporal orbital mass. Excision of the encapsulated mass was performed. Histopathology revealed an acellular, amorphous, granular and eosinophilic material with no evidence of malignancy. These were consistent with a foreign body. Postoperatively, there were improvements in ocular motility and hypoglobus.@*Conclusion@#In patients who present with limited ocular motility and have undergone scleral buckling, hydrogel scleral buckle overexpansion should be considered. Excision of such implants is warranted to resolve the signs and symptoms and confirm the etiology.

The effects of natural polysaccharide supramolecular hydrogel on bacteriostatic activity and biofilm clearance of berberine / 药学学报

Taking berberine (BBR) as an example, to study whether the supramolecular hydrogel formed by berberine and lotus root starch (Nelumbo nucifera Gaertn; LRS), a natural polysaccharide, affects the inhibition to Staphylococcus aureus and the ability of biofilm clearance. The chemical structure and rheological properties of BBR@LRS gel were characterized by infrared spectroscopy and rheometer. The in vitro release of supramolecular hydrogel was observed at pH = 1.2 and pH = 7.4. Broth dilution method and biofilm clearence experiment were used to observe the bacteriostasis and biofilm clearance respectively. Cytotoxicity test and in vitro hemolysis test were used to evaluate the biosafety preliminarily. The results showed that the LRS polysaccharide hydrogel could encapsulate BBR, and there was an interaction between them. The BBR@LRS gel had good rheological properties and biosafety, and played a role in solubility enhancement and slow release of BBR, which was stronger than BBR in inhibiting the growth of Staphylococcus aureus and clearing biofilm. This study provides reference for the effect of natural polysaccharide supramolecular hydrogels on biological functions of active components of traditional Chinese medicine.

Progress in research on hydrogel and medium permeability / 中国生物制品学杂志

@#As a new research field,gel has been paid more attention and widely used for studies on tissue engineering,drug delivery and biosensor. Hydrogel is the carrier of cells,while the cell survival and death are keys to the construction of tissues and organs. However,the cell viability and biological behavior are limited by the exchange of hydrogel and nutrients in medium. This review summarizes the types of hydrogel,exchange mode of hydrogel and nutrients in medium and the relevant influencing factors,which will provide a reference for the development and research of tissue bioengineering.

Research progress on the application of hydrogel spacer in brachytherapy for gynecological tumors / 中华放射肿瘤学杂志

Radiotherapy is an important treatment of gynecological tumors. Although novel techniques or measures in recemy years have improved the tumor control rate and reduced radiation toxicity, radiation toxicity remains a major problem due to the location of some key organs adjacent to the tumor. A new material-hydrogel, as an organ spacer, provides a new method to reduce the radiotherapy toxicity. In this article, the application of hydrogel as an organ spacer in brachytherapy for gynecological tumors was reviewed from the aspects of hydrogel characteristics, suitable population, mode of injection, interval distance and dose effect, clinical benefits and cost effectiveness, etc.