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Nowadays, there are still many challenges to skin regeneration. As a new type of skin substitute, hydrogel has emerging gradually with its excellent properties. However, it is still a challenge to combine with biological active agents to facilitate skin regeneration. Under the circumstance, we synthesized arginine-based poly(ester amide) (Arg-PEA) and hyaluronic acid (HA-MA), and combined them into new hybrid hydrogels via photo-crosslinking. We found that the internal structure and physicochemical properties of hybrid hydrogels were greatly improved with the increase of content of Arg-PEA. Therefore, we designed hybrid hydrogels with 5 wt% and 10 wt% of Arg-PEA content, respectively. Besides, we selected the corresponding anti-inflammatory (CRP, TNF-α) indicators to detect the anti-inflammatory properties of the hybrid hydrogels at the protein level, and the corresponding antioxidant indicators (SOD, GSH/GSSG, MDA) were selected to investigate the antioxidant properties of hybrid hydrogels at the cellular level in vitro. In addition, we also selected relevant genes to test the effect of hybrid hydrogels on fibrosis and vascularization in the process of skin wound healing in vitro and verified them in vivo with a mouse dorsum wound model. The results confirmed that Arg-PEA/HA-MA (AH) hybrid hydrogel was a prospective scaffold material for skin regeneration.

Antioxidant hydrogel has exhibited great potential for diabetic wound treatment. However, it is still a difficult challenge to realize reactive oxygen species (ROS) scavenging in an intelligent manner. Herein, we designed a novel glucose-responsive antioxidant hybrid hydrogel for enhanced diabetic wound repair. In this study, phenylboronic acid (PBA) with unique glucose-sensitivity was modified onto a hyaluronic acid (HA) chain by one-step synthesis, which was then incorporated into a polyethylene glycol diacrylates (PEG-DA) hydrogel matrix to obtain a novel hybrid hydrogel (PEG-DA/HA-PBA). Then, myricetin (MY) molecules with strong antioxidant activity were immobilized into the hybrid hydrogel by the formation of a dynamic borate bond between the polyphenol group of MY and the phenylboronic acid group of HA-PBA. The PEG-DA/HA-PBA/MY (PHM) hybrid hydrogel achieved glucose-triggered MY release, efficient ROS-scavenging (80.0%), and also reshaped the hostile oxidative wound microenvironment (reduced MDA activity and increased SOD and GSH/GSSG levels). Furthermore, in vitro and in vivo results indicated that the PHM hydrogel platform effectively ameliorated the inflammatory response (decreased IL-6 and increased Il-10 expression), accelerated angiogenesis (increased VEGF and CD 31 expression), and increased tissue remodeling within 20 days, which was better than the nonresponsive PEG-DA/MY (PM) hydrogel platform in promoting diabetic wound healing. All results strongly suggested that this novel glucose-responsive antioxidant hybrid hydrogel platform has great potential in diabetic wound repair.

Stem cell therapy has shown unparalleled potential in tissue engineering, but it still faces challenges in the regulation of the stem cell fate. Inspired by the native stem cell niche, a variety of engineered hydrogels with programmed physicochemical properties have been developed to achieve flexible and controlled regulation of the stem cell fate, greatly enhancing the clinical application prospects of stem cell therapy in tissue regeneration. Here, the recent advances in hydrogels for stem cell therapy are summarized. The mechanism by which hydrogels regulate the stem cell fate is first presented, followed by the application of hydrogel/stem cell therapies in tissue engineering, including bone tissue engineering, skin wound healing and central nervous system regeneration. Finally, the current challenges and future prospects of hydrogel/stem cell therapies in tissue engineering are discussed. The purpose of this review is to provide a reference for the crossover and integration of hydrogels and stem cells in the field of tissue engineering.

In studies on wound-dressing materials, bioactive materials have been developed rapidly to accelerate wound healing. In recent years, scientists have studied arginine as a bioactive component due to its excellent biosafety, antimicrobial properties and therapeutic effects on wound healing. Surprisingly, arginine therapy is also used under specific pathological conditions, such as diabetes and trauma/hemorrhagic shock. Due to the broad utilization of arginine-assisted therapy, we present the unique properties of arginine for healing lesions of damaged tissue and examined multiple arginine-based systems for the application of wound healing. This review shows that arginine-based therapy can be separated in two categories: direct supplemental approaches of free arginine, and indirect approaches based on arginine derivatives in which modified arginine can be released after biodegradation. Using these two pathways, arginine-based therapy may prove to be a promising strategy in the development of wound curative treatments.

The fabrication of functional tissue or organs substitutes has always been the pursuit of goals in the field of tissue engineering. But even biocompatible tissue-engineered scaffolds still suffer from immune rejection, subsequent long-term oxidative stress and inflammation, which can delay normal tissue repair and regeneration. As a well-known natural antioxidant, polyphenols have been widely used in tissue engineering in recent years. The introduced polyphenols not only reduce the damage of oxidative stress to normal tissues, but show specific affinity to functional molecules, such as receptors, enzyme, transcription and transduction factors, etc. Therefore, polyphenols can promote the recovery process of damaged tissues by both regulating tissue microenvironment and participating in cell events, which embody specifically in antioxidant, anti-inflammatory, antibacterial and growth-promoting properties. In addition, based on its hydrophilic and hydrophobic moieties, polyphenols have been widely used to improve the mechanical properties and anti-degradation properties of tissue engineering scaffolds. In this review, the research advances of tissue engineering scaffolds containing polyphenols is discussed systematically from the aspects of action mechanism, introduction method and regulation effect of polyphenols, in order to provide references for the rational design of polyphenol-related functional scaffolds.

Methionine (Met), an essential amino acid in the human body, possesses versatile features based on its chemical modification, cell metabolism and metabolic derivatives. Benefitting from its multifunctional properties, Met holds immense potential for biomedical applications. In this review, we systematically summarize the recent progress in Met-based strategies for biomedical applications. First, given the unique structural characteristics of Met, two chemical modification methods are briefly introduced. Subsequently, due to the disordered metabolic state of tumor cells, applications of Met in cancer treatment and diagnosis are summarized in detail. Furthermore, the efficacy of S-adenosylmethionine (SAM), as the most important metabolic derivative of Met, for treating liver diseases is mentioned. Finally, we analyze the current challenges and development trends of Met in the biomedical field, and suggest that Met-restriction therapy might be a promising approach to treat COVID-19.

Biomimetic scaffolds present the promising potential for bone regeneration. As a natural gel-like traditional food, tofu with porous architecture and proved biological safety indicated a good potential to be a natural scaffold and easy to be improved by surface modification. Hereon, we fabricated the tofu-based scaffolds and systematically explored the potential for bone tissue engineering. In addition, the collagen has been introduced by simple coating to further enhance the surface compatibility of the tofu-based scaffold in bone regeneration. The results showed that the tofu-based scaffolds possessed good porous structure and cytocompatibility. Notably, the tofu-based scaffolds could improve the expression of osteogenesis-related genes and proteins, leading to better bone regeneration after 2 months of implantation. All the results indicated that tofu would become an outstanding sustainable natural porous scaffold for bone regeneration with excellent bioactivities.

Various intelligent hydrogels have been developed for biomedical applications because they can achieve multiple, variable, controllable and reversible changes in their shape and properties in a spatial and temporal manner, thus greatly adapting to the complex application environments

Baicalin, extracted from traditional Chinese medicine Scutellaria baicalensis Georg, possesses multiple pharmacological activities and has great potential for chronic skin wound repair. However, the poor solubility and lack of suitable vehicles greatly limit its further application. Herein, we proposed a convenient and robust strategy, employing PBS solution as solvent, to enhance the solubility of baicalin. Furthermore, we constructed injectable baicalin/F127 hydrogels to study their application in skin wound treatment. The composition and temperature sensitivity of baicalin/Pluronic® F-127 hydrogels were confirmed by FTIR and rheological testing, respectively. In vitro release measurement indicated that the first order model was best fitted with the release profile of baicalin from hydrogel matrix. Besides, MTT assay, AO/EO staining assay as well as hemolytic activity test revealed the excellent cytocompatibility of baicalin/F127 hydrogels. Antioxidant activity assay demonstrated the cytoprotective activity of baicalin/F127 hydrogels against reactive oxygen species (ROS). Furthermore, the in vivo experiments exhibited the ability of baicalin/F127 hydrogel to accelerate wound healing. In conclusion, this novel injectable baicalin/F127 hydrogel should have bright application for chronic wound treatment.

Recently, tissue engineering has developed into a powerful tool for repairing and reconstructing damaged tissues and organs. Tissue engineering scaffolds play a vital role in tissue engineering, as they not only provide structural support for targeted cells but also serve as templates that guide tissue regeneration and control the tissue structure. Over the past few years, owing to unique physicochemical properties and excellent biocompatibility, various types of two-dimensional (2D) nanomaterials have been developed as candidates for the construction of tissue engineering scaffolds, enabling remarkable achievements in bone repair, wound healing, neural regeneration, and cardiac tissue engineering. These efforts have significantly advanced the development of tissue engineering. In this review, we summarize the latest advancements in the application of 2D nanomaterials in tissue engineering. First, each typical 2D nanomaterial is introduced briefly, followed by a detailed description of its applications in tissue engineering. Finally, the existing challenges and prospects for the future of the application of 2D nanomaterials in tissue engineering are discussed.

Although intelligent hydrogels have shown bright potential application in biomedical fields, they were prepared by conventional methods and still face many serious challenges, such as uncontrollable stimulus-response and low response sensitivity. Recently, RAFT polymerization provides a versatile strategy for the fabrication of intelligent hydrogels with improved stimulus-response properties, owing to the ability to efficiently construct hydrogel precursors with well-defined structure, such as block copolymer, graft copolymer, star copolymer. In this review, we summarized the recent progress on intelligent hydrogels based on RAFT polymerization with emphasis on their fabrication strategies and applications for controlled drug delivery.

Gene therapy is deemed to be a powerful and promising tool to treat many stubborn diseases in the near future. For successful gene therapy, gene vectors play a vital role as they determine whether the edited gene can be loaded and transferred into target cells effectively. However, traditional gene vectors face some serious challenges, especially in biosafety and trans-membrane efficiency. Recently, inspired by cell-penetrating peptides (CPPs) possessing excellent biosafety and trans-membrane efficiency, various types of arginine-based gene delivery systems have been designed and fabricated. In this review, the superiority and mechanism of action of arginine in promoting membrane penetration are briefly presented. Then, four types of arginine-based gene vectors, namely, typical linear polymers, dendrimers, lipids and arginine-based composite gene vectors and their applications are discussed in detail. Finally, the current challenges and future perspectives of arginine-based gene delivery systems are discussed.

Hyaluronic acid (HA)-based antioxidant hydrogels have achieved remarkable results in diabetic wound repair. However, the realization of their glucose-responsive antioxidant functions remains a significant challenge. In this study, we modified hyaluronic acid methacrylate (HAMA) with phenylboronic acid (PBA) and developed a glucose-responsive HA derivative (HAMA-PBA). A glucose-responsive HAMA-PBA/catechin (HMPC) hydrogel platform was then fabricated by forming a borate ester bond between HAMA-PBA and catechin. The results showed that the HMPC hybrid hydrogel not only had a three-dimensional network structure and Young's modulus similar to those of skin tissue, but also possessed biocompatibility. The HMPC hydrogel also showed unique glucose-responsive catechin release behavior and remarkable antioxidant capability, which could effectively eliminate intracellular reactive oxygen species and protect cells from oxidative stress damage (increased superoxide dismutase activity, stabilized reduced glutathione/oxidized glutathione ratio, and reduced malondialdehyde content). Additionally, in vitro and in vivo experimental results showed that the HMPC hydrogel effectively promoted angiogenesis (enhanced VEGF and CD31 expression) and reduced inflammatory responses (decreased IL-6 level and increased IL-10 level), thus rapidly repairing diabetic wounds (within three weeks). This was a significant improvement as compared to that observed for the untreated control group and the HMP hydrogel group. These results indicated the potential for the application of the HMPC hydrogel for treating diabetic wounds. STATEMENT OF SIGNIFICANCE: At present, the delayed closure rate of diabetic chronic wounds caused by excessive reactive oxygen species (ROS) remains a worldwide challenge. Hyaluronic acid (HA)-based antioxidant hydrogels have made remarkable achievements in diabetic wound repair; however, the realization of their glucose-responsive antioxidant functions is a tough challenge. In this work, we developed a novel HA-based hydrogel platform with glucose-responsive antioxidant activity for rapid repair of diabetic wounds. In vitro and in vivo experimental results showed that the HMPC hydrogel could effectively promote angiogenesis (enhanced VEGF and CD31 expression) and reduce inflammatory response (decreased IL-6 level and increased IL-10 level), thus rapidly repairing diabetic wounds (within 3 weeks). These results indicated the potential of the HMPC hydrogel for application in diabetic wound treatment.

Hot-melt blending has been widely used in the pharmaceutical industry to produce drug delivery systems, however, realizing the controlled drug release behavior of a hot-melt blended medicament it is still a tough challenge. In this study, we developed a simple and effective heat treatment method to adjust the drug release behavior, without the addition of any release modifiers. Thin metoprolol tartrate (MPT)/poly(ε-caprolactone) (PCL) tablets were prepared through hot-melt processing, and different morphologies of MPT were obtained by altering processing temperatures and the following heat treatment. MPT particles with different particle sizes were obtained under different processing temperatures, and fibrous crystals of MPT were fabricated during the following heat treatment. Different morphological structures of MPT adjusted the drug diffusion channel when immersed in phosphate-buffered saline (PBS), and various drug release behaviors were approached. After being immersed for 24 h, 7% of the MPT was released from the blend processed at 130 °C, while more than 95% of the MPT were released after the following heat treatment of the same sample. Thus, flexible drug release behaviors were achieved using this simple and effective processing manufacture, which is demonstrated to be of profound importance for biomedical applications.

Background: As a leading cause of deaths worldwide, lung cancer is a collection of diseases with diverse etiologies which includes non-small-cell lung cancer (NSCLC). Increasing evidence reported that aberrant expression of BRAF activated non-coding RNA (BANCR) was involved in the tumorigenesis and progression of various malignancies. Purpose and methods: However, its role in NSCLC has not been completely clarified. In the present study, we identified the role of BANCR in the regulation of NSCLC cell viability, invasion, and apoptosis. Down-regulation of BANCR expression was significantly observed in different NSCLC cell lines (A549, H1299, H1650, H1975, SPC-A1, and PC-9), tumor tissue from NSCLC mouse model and 30 human NSCLC tissues compared with adjacent normal tissues. Result: Overexpression of BANCR in these six NSCLC cell lines attenuated the cell viability and invasion. An increased apoptotic level caused by BANCR overexpression was also detected and displayed a conversed influence on Bcl-2 and Bax expression in mRNA and protein level. Furthermore, we identified the effect of BANCR overexpression on tumor growth in NSCLC mouse model. The restoration of BANCR expression inhibits NSCLC. Conclusion: Taken together, our findings shed an insight on the novel molecular mechanisms of lung NSCLC oncogenesis and provide the information for new therapeutic approaches on the disease.

Gelatin methacryloyl (GelMA)-based biomaterials have been widely used in various biomedical applications due to their suitable biological properties and tuneable physical characteristics. In particular, GelMA can be used as a versatile matrix for bone tissue engineering scaffolds via various strategies to overcome major obstacles such as insufficient mechanical property and uncontrollable degradation. This review presents the research status of GelMA, its structure and function, GelMA-based biomaterials and the development of methods along with their existing challenges.

Edible materials have attracted increasing attention because of their excellent properties including availability, biocompatibility, biological activity, and biodegradability. Natural polysaccharides, phenolic compounds, and proteins are widely used in tissue regeneration. To better characterize their healing effect, this review article describes the applications of edible materials in tissue regeneration including wound healing and bone tissue regeneration. As an introduction to the topic, their sources and main bioactive properties are discussed. Then, the mechanism by which they facilitate wound healing based on their hemostasis, antibacterial, anti-inflammatory, and antioxidant properties is systematically investigated. Moreover, a more comprehensive discussion is presented on the approaches by which edible materials can be used as scaffolds or agents for the provision of the components of natural bones for regulating the level of osteogenesis-related cytokines to enhance bone repair. Finally, the prospects of edible materials for tissue regeneration are discussed.

Objective: Proximal gastrectomy was acted as a function-preserving operation for upper third gastric cancer. The aim of this study is to compare the surgical short-term outcomes between proximal gastrectomy with gastric tube reconstruction and proximal gastrectomy with Jejunal interposition reconstruction in the upper third gastric cancer. Methods: A retrospective review of 301 patients who underwent proximal gastrectomy with jejunal interposition (JI) or gastric tube (GT) at the Harbin Medical University Cancer Hospital between June 2007 and December 2016 was performed. The Gastrointestinal Symptom Rating Scale (GSRS) and Visick grade were used to evaluate the post-gastrectomy syndromes. The gastrointestinal fiberoscopy was used to evaluate the prevalence and severity of reflux esophagitis by Los Angeles (LA) classification system. Results: The JI group had a longer operation time than GT group (220±52 vs 182±50 min), whereas there was no significant difference in blood loss. Compared to the GT group, the Visick grade and GSRS score were significantly higher than that of the JI group. The reflux esophagitis of GT group was significantly higher than that of the JI group. Conclusion: Proximal gastrectomy is well tolerated, with excellent short-outcomes in patients with upper third gastric cancer . C ompared with GT construction, JI construction has clear functional advantages and may provide better quality of life for patients with upper third gastric cancer.

Currently, the treatment and care of diabetic wounds, which generally possess the characteristics of a high amputation rate, high recurrence rate and high mortality, has developed into a worldwide challenge. Wound dressings have been playing an important role in diabetic wound treatment and continuously innovated to obtain many amazing properties. Among them, hydrogel dressings have become one of the most attractive and promising wound dressings because of their considerable moisture retention, biocompatibility and therapeutic properties. In recent years, with the in depth understanding of the pathogenesis of diabetic wounds, various functionalized hydrogel dressings have been reported and shown encouraging results, which has brought great benefits to the improvement of diabetic wounds. In this work, we will systematically and comprehensively summarize the advances of hydrogel dressings in diabetic wounds, aiming to provide not only theoretical support for hydrogel dressing devising but also inspiration for diabetic wound treatment.

Tofu not only is a delicious vegetarian food, but also shows potential biomedical applications for its high protein content and typical porous scaffold structure. Herein, two kinds of porous soybean scaffolds were developed, the first based on the traditional tofu manufacturing processes, the second modified via covalent crosslinking. The morphology, physicochemical properties and biocompatibility in vitro and in vivo were systematically investigated. A similar porous micromorphology was observed in both the tofu scaffolds and crosslinked soybean protein scaffolds. Both scaffolds exhibited good cell proliferation and cellular adherence. No obvious inflammatory response was observed after subcutaneous implantation tests for either material. These results demonstrated that the tofu scaffolds or soybean protein scaffolds fabricated by tofu processing have potential as new food-source biomaterials in tissue engineering applications.

The clinical outcome after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) is diverse in infertility patients with polycystic ovary syndrome (PCOS). The aim of this study was to develop a nomogram based on an association of patients’ characteristics to predict the live birth rate in PCOS patients. All women in a public university hospital who attempted to conceive by IVF/ICSI for PCOS infertility from January 2014 to October 2018 were included. The nomogram was built from a training cohort of 178 consecutive patients and tested on an independent validation cohort of 81 patients. PCOS was confirmed in all participants. Three variates significantly associated with live birth rate of PCOS patients were BMI, total serum cholesterol (TC) and basal FSH. This predictive model built on the basis of BMI, TC, basal FSH, type of embryo transferred and age showed good calibration and discriminatory abilities, with an area under the curve (AUC) of 0.708 (95% CI 0.632–0.785) for the training cohort. The nomogram showed satisfactory goodness-of-fit and discrimination abilities in the independent validation cohort, with an AUC of 0.686 (95% CI 0.556–0.815). Our simple evidence-based nomogram presents graphically risk factors and prognostic models for IVF/ICSI outcomes in patients with PCOS, which can offer useful guidance to clinicians and patients for individual adjuvant therapy.

Because of unparalleled advantages over other cells, stem cells are widely used in genetic diagnosis, drug delivery, and regenerative medicine. However, because the content of stem cells in the organism is far from satisfactory, it is of great significance of stem cells to in vitro proliferation and differentiation. However, many stem cell cultures have low expansion efficiency and stem cells lose their value-adding ability and differentiation ability after many generations of culture. To solve these problems, people hope to more realistically simulate the microenvironment in which stem cells grow in vivo. Cell scaffolds gradually evolve from 2D structures to 3D structures. The addition of growth factors influences cell behavior from internal biochemical conditions and the development of smart bioreactors gradually make progress to more precise regulate the external conditions of stem cell. In this paper, the key factors for constructing the microenvironment of stem cell growth were analyzed, and we revie...

The cyclodextrin (CD) based host–guest inclusion complexation between cyclodextrins (CDs) and guest moieties has inspired the fabrication of novel supramolecular hydrogels for biomedical applications. From a topology of view, this article reviews the recent developments of two kinds of CD-based supramolecular hydrogels and their applications in biomedical fields respectively. On one hand, supramolecular hydrogels derived from CD-based poly(pseudo)rotaxanes generally displayed thixotropic and reversible properties and have been extensively developed as injectable drug delivery systems. On the other hand, supramolecular hydrogels based on the host–guest interaction between CDs and small guest moieties generally exhibited stimuli-responsive behaviors, typically the release of therapeutic agents. The development of CD-based supramolecular hydrogels provides a new platform for the design of novel biomaterials.

The discovery of novel methods to fabricate optimal scaffolds that mimic both mechanical and functional properties of the extracellular matrix (ECM) has always been the “holy grail” in tissue engineering. In recent years, electrospinning has emerged as an attractive material fabrication method and has been widely applied in tissue engineering due to its capability of producing non-woven and nanoscale fibers. However, from the perspective of biomimicry, it is difficult for single-component electrospun fiber membranes to achieve the biomimetic purposes of the multi-component extracellular matrix. Based on electrospinning, various functional components can be efficiently and expediently introduced into the membranes, and through the complementation and correlation of the properties of each component, composite materials with comprehensive and superior properties are obtained while maintaining the primitive merits of each component. In this review, we will provide an overview of the attempts made to fabricate electrospinning-based composite tissue engineering materials in the past few decades, which have been divided into organic additives, inorganic additives and organic–inorganic additives.

Functional polymeric drug delivery systems have generated enormous interest due to their excellent features. This paper reports the development of a novel pH and redox dual-sensitive polymer for anticancer paclitaxel (PTX) delivery applications. The polymer was prepared by polycondensation of disulfide bond-containing dimethyl l-cystinate (Cys) and polycaprolactone (PCL) oligomer via a pH-responsive imine bond. Using the nanoprecipitation method, the polymer can be formulated as nanoparticles (poly(Cys-PCL)/PTX NPs) with a diameter less than 100 nm, as measured by TEM and DLS. The NPs release PTX significantly faster at mildly acidic pH and high concentrations of GSH, exhibiting almost no burst release under the physiological conditions of plasma. Notably, the NPs efficiently deliver PTX to the tumor cells, which was more cytotoxic to 4T1 cancer cells than the pure PTX alone. In vivo results reveal an excellent tumor inhibiting ability, good drug tolerability and biosafety of poly(Cys-PCL)/PTX NPs. Overall, the poly(Cys-PCL)/PTX NPs platform may have greater potential in enhancing cancer therapy.

To include the two key parameters of circulating air volume and instantaneous ultraviolet illuminance, as well as the minor influencing factors such as temperature, humidity, comings and goings of personnel and other parameters into the scope of conventional monitoring, and monitor and alarm each parameter, the key problem is to design the data transmission of sensors of existing products and debug the network management system, and solve every problem in the research process through the cycle of experiment-trial-experiment. The specific functions of a single instrument and system software can be achieved by solving the key links such as type selection of various sensors, circuit interface, guarantee measures for measurement accuracy of various parameters, research and development of networked air disinfection management system software, design of WiFi interface, cost control of single machine and system and so on. And ultraviolet luminance sensors can be used to monitor the ultraviolet intensity in the machine in real time, and monitor 7 parameters, including circulating air volume, ozone concentration, comings and goings of personnel, temperature, humidity and leaked ultraviolet intensity.

Homogeneous alginate hydrogels were facilely fabricated through solution extrusion process. CaCO3 and D-glucono-δ-lactone (GDL) were used as the gelation agents. The slow gelation of alginate was realized by the in-situ release of Ca2+ from CaCO3 particles induced by hydrolysis of GDL to reduce pH. Slight gelation during the extrusion caused the enhanced strength of the alginate solutions, leading to the extrudability of the blends. This method enables to produce alginate hydrogels in a single step via extrusion, which is economically advantageous to conventional lab-scale preparation for mass production. Three different drugs, ibuprofen, acetaminophen, and methylthionine chloride, were used as model drugs to evaluate the drug release behavior of the alginate hydrogels. It was demonstrated that the drug release behavior was significantly adjusted by both the drug solubility and the ionic interaction between alginate and the drug molecule. It was shown that solution extrusion process is a feasible ...

To investigate 4-HNE expression in diabetic rat kidneys and the protective effect of probucol. Diabetic rat models were established. Diabetic rats with successful modeling were randomly divided into the diabetic group (group D) and probucol treated group (group P). Normal rats were put into the control group (group C). Rats in group P were treated with probucol (110 mg/kg day), and rats in groups D and C were given equal volume of water instead. Serum creatinine (SCr), urea nitrogen (BUN), triglyceride (TG), total cholesterol (TC), and 24-h urinary protein were measured at the 4th, 8th, and 12th weeks. Periodic acid-schiff (PAS) staining and hematoxylin-eosin (HE) staining were used to evaluate the renal pathological changes. The immunohistochemistry and Western-blot were used to detect 4-HNE expression in renal tissue. The SCr, BUN, TG, TC, and 24-h urinary protein in group D increased in the 4th, 8th, and 12th weeks and were higher than those in group C (P

In this study, different types of poly(ϵ-caprolactone) (PCL)-based matrices were prepared by hot-melt extrusion. Methylene blue (MB) was used as a model drug, and various amounts and types of hydrophilic components (polyethylene glycol, PEG or polyethylene oxide, PEO) were added to the extrudates as release rate modifiers. The drug release mechanism and kinetics from these extrudates were investigated. Scanning electron microscopy (SEM) and micro-Fourier transform infrared spectroscopy (micro-FTIR) results revealed the dissolution of the hydrophilic components (PEG or PEO) during the drug release, and in-vitro release tests exhibited the tailorable release behavior of MB from the PCL/hydrophilic components. Based on the experimental results, it was speculated that the release kinetics of MB from the PCL/hydrophilic components was a combination of diffusion and dissolution models.

Chemotherapy, combined with other treatments, is widely applied in the clinical treatment of cancer. However, deficiencies inherited from the traditional route of administration limit its successful application. With the development of nanotechnology, a series of smart nanodelivery systems have been developed to utilize the unique tumor environment (pH changes, different enzymes, and redox potential gradients) and exogenous stimuli (thermal changes, magnetic fields, and light) to improve the curative effect of anticancer drugs. In this review, endogenous and exogenous stimuli are briefly introduced. Among these stimuli, various redox-sensitive linkages are primarily described in detail, and their application with self-assembled nanoparticles is recounted. Finally, the application of redox-responsive self-assembled nanoparticles in cancer therapy is summarized.

Many hydrogel scaffolds for bone regeneration do not satisfy clinical needs due to uncontrollable mechanical properties and calcium supply and a lack of outstanding osteogenic functions. Herein, a novel acid-responsive composite hydrogel scaffold platform was developed to provide controllable stiffness and calcium supply for enhanced bone regeneration. For this purpose, pluronic F127 diacrylate (F127-DA) was selected as the model scaffold matrix material due to its good biocompatibility and easy formulation capability. Nano-CaCO3 was chosen as the composite material to provide an acid-responsive property and controlled calcium supply. The acid-responsive nano-CaCO3 may lead to space-controlled distribution of nano-CaCO3 in a hydrogel under acid treatment, leading to effective regulation of the mechanical properties of the hydrogel scaffold. Furthermore, the hydrogel may efficiently modulate the expression of Col1, BMP2 and OPN, which are beneficial for osteogenesis. In vivo studies in a rabbit skull bone defect model indicated that this F127-DA/nano-CaCO3 composite hydrogel platform performed better in bone regeneration than a pure F127-DA hydrogel. Therefore, this responsive composite hydrogel platform provides a simple and robust strategy for developing advanced composite hydrogel scaffolds for effective bone repair.

Bone transplantations are still facing many serious challenges, hydrogel as a new kind of artificial bone substitutes has developed into a promising bone scaffold material. However, it is still a challenge to combine bioactive agents and hydrogel matrix to promote osteoinductivity. Herein, we developed a novel bioactive hydrogel based on arginine-based unsaturated poly (ester amide) (Arg-UPEA) and methacrylated hyaluronic acid (HA-MA) via photo-crosslinking. As the results indicated, we found that the introduction of Arg-UPEA into HA-MA hydrogels could finely modulate their compressive modulus, swelling level and porous structure. Besides, among groups of different feed ratio, groups of 10 % and 15 % of Arg-UPEA content effectively enhanced osteogenic differentiation in osteoblasts when compared with HA-MA hydrogel. Furthermore, better bone regeneration and expression of osteogenesis-related factors in vivo also verified the Arg-UPEA/HA-MA hybrid hydrogels as a promising scaffold material for bone tissue engineering.

Studies have confirmed that lipid-lowering drugs can effectively control the morbidity and mortality of cardiovascular and cerebrovascular diseases and statins are the most widely used. The aim of this study is to investigate the effect and mechanism of different statins on atherosclerotic patients. The patients were randomly divided into 4 groups according to the digital method, and the patients were treated with conventional therapy, simvastatin treatment, pravastatin treatment, atorvastatin treatment. It is concluded that statins are safe, effective and reliable for the treatment of atherosclerosis, and worthy of clinical promotion. The results also showed that after 6 months of taking statins, the levels of NO and NOS increased, the thickness of carotid intima-media became thinner and the plaque score decreased. This study provides a basis for elucidating the role of statins in the body.