Quaternary ammonium salt of chitosan: preparation and antimicrobial property for paper

Carboxymethyl cellulose-chitosan edible films for food packaging: A review of recent advances

Polysaccharide-based edible films have been widely developed as food packaging materials in response to the rising environmental concerns caused by the extensive use of plastic packaging. In recent years, the integration of carboxymethyl cellulose (CMC) and chitosan (CS) for a binary edible film has received considerable interest because this binary edible film can retain the advantages of both constituents (e.g., the great oxygen barrier ability of CMC and moderate antimicrobial activity of CS) while mitigating their respective disadvantages (e.g., the low water resistance of CMC and poor mechanical strength of CS). This review aims to present the latest advancements in CMC-CS edible films. The preparation methods and properties of CMC-CS edible films are comprehensively introduced. Potential additives and technologies utilized to enhance the properties are discussed. The applications of CMC-CS edible films on food products are summarized. Literature shows that the current preparation methods for CMC-CS edible film are solvent-casting (main) and thermo-mechanical methods. The CMC-CS binary films have superior properties compared to films made from a single constituent. Moreover, some properties, such as physical strength, antibacterial ability, and antioxidant activity, can be greatly enhanced via the incorporation of some bioactive substances (e.g. essential oils and nanomaterials). To date, several applications of CMC-CS edible films in vegetables, fruits, dry foods, dairy products, and meats have been studied. Overall, CMC-CS edible films are highly promising as food packaging materials.

Modified chitosan: Insight on biomedical and industrial applications

Chitosan (CS), a by -product of chitin deacetylation can be useful in a broad range of purposes, to mention agriculture, pharmaceuticals, material science, food and nutrition, biotechnology and of recent, in gene therapy. Chitosan is a highly desired biomolecule due to the existence of many sensitive functional groups inside the molecule and also because of its net cationicity. The latter provides flexibility for creating a wide range of derivatives for particular end users across various industries. This overview aims to compile some of the most recent research on the bio-related applications that chitosan and its derivatives can be used for. However, chitosan's reactive functional groups are amendable to chemical reaction. Modifying the material to show enhanced solubility, a greater range of application options and pH-sensitive targeting and others have been a major focus of chitosan research. This review describes the modifications of chitosan that have been made to improve its water solubility, pH sensitivity, and capacity to target chitosan derivatives. Applying the by-products of chitosan as antibacterial, in targeting, extended release and as delivery systems is also covered. The by-products of chitosan will be important and potentially useful in developing new biomedical drugs in time to come.

A review of passive acid mine drainage treatment by PRB and LPB: From design, testing, to construction

An extensive volume of acid mine drainage (AMD) generated throughout the mining process has been widely regarded as one of the most catastrophic environmental problems. Surface water and groundwater impacted by pollution exhibit extreme low pH values and elevated sulfate and metal/metalloid concentrations, posing a serious threat to the production efficiency of enterprises, domestic water safety, and the ecological health of the basin. Over the recent years, a plethora of techniques has been developed to address the issue of AMD, encompassing nanofiltration membranes, lime neutralization, and carrier-microencapsulation. Nonetheless, these approaches often come with substantial financial implications and exhibit restricted long-term sustainability. Among the array of choices, the permeable reactive barrier (PRB) system emerges as a noteworthy passive remediation method for AMD. Distinguished by its modest construction expenses and enduring stability, this approach proves particularly well-suited for addressing the environmental challenges posed by abandoned mines. This study undertook a comprehensive evaluation of the PRB systems utilized in the remediation of AMD. Furthermore, it introduced the concept of low permeability barrier, derived from the realm of site-contaminated groundwater management. The strategies pertaining to the selection of materials, the physicochemical aspects influencing long-term efficacy, the intricacies of design and construction, as well as the challenges and prospects inherent in barrier technology, are elaborated upon in this discourse.

Packaging films based on biopolymers from seafood processing wastes: Preparation, properties, and their applications for shelf-life extension of seafoods-A comprehensive review

Biopolymers derived from seafood processing byproducts are used to prepare active and biodegradable films as the packaging of food products. These films possess bioactivities to enhance the shelf life of packed foods by proactively releasing antimicrobial/antioxidative agents into the foods and providing sufficient barrier properties. Seafood processing byproducts are an eminent source of valuable compounds, including biopolymers and bioactive compounds. These biopolymers, including collagen, gelatin, chitosan, and muscle proteins, could be used to prepare robust and sustainable food packaging with some antimicrobial agents or antioxidants, for example, plant extracts rich in polyphenols or essential oils. These active packaging are not only biodegradable but also prevent the deterioration of packed foods caused by spoilage microorganisms as well as chemical deterioration. Seafood discards have a promising benefit for the development of environmentally friendly food packaging systems via the appropriate preparation methods or techniques. Therefore, the green packaging from seafood leftover can be better exploited and replace the synthetic counterpart.

Bandage modified with antibacterial films of quaternized chitosan & sodium carboxymethyl cellulose microgels/baicalein nanoparticles for accelerating infected wound healing

Wound dressings capable of sterilizing pathogenic bacteria and scavenging free radicals are important to inhibit bacterial invasion and accelerate wound healing. The target of this work is to develop an antibacterial dressing by modifying bandages with films composed of biological macromolecule microgels and baicalein@tannic acid (Bai@TA) nanoparticles (NPs). Firstly, hydrophobic Bai was made into water soluble Bai@TA NPs using a solvent exchange method with TA as stabilizer. Polymeric microgels of sodium carboxymethyl cellulose (CMC)&hydroxypropyltrimethyl ammonium chloride chitosan (HACC) were then prepared by a simple blending method. Further, CMC&HACC/Bai@TA multilayer films were deposited on medical bandages by using a layer-by-layer assembly technique to obtain an antibacterial dressing. The as-prepared dressings showed great antibacterial ability against E. coli, S. aureus and methicillin resistant Staphylococcus aureus (MRSA), excellent antioxidant activity and good biological safety. In addition, compared to conventional medical bandages, the dressings could efficaciously diminish inflammation in the wound, accelerate skin regeneration and functional restoration, and promote the in vivo healing speed of full-thickness skin wounds infected by MRSA. We believe that as a low-cost but effective wound dressing, the antibacterial bandage modified with CMC&HACC/Bai@TA films has potentials to replace traditional dressings in the clinical management of infected wounds.

High Strength, Conductivity, and Bacteriostasis of the P(AM-co-AA)/Chitosan Quaternary Ammonium Salt Composite Hydrogel through Ionic Crosslinking and Hydrogen Bonding

Traditional hydrogels with a single-crosslinked network structure suffer from poor stretchability, low sensitivity, and easy contamination, which seriously affect their practical application in the strain sensor field. To overcome these shortcomings, herein, a multiphysical crosslinking strategy (ionic crosslinking and hydrogen bonding) was designed to prepare a hydrogel strain sensor based on chitosan quaternary ammonium salt (HACC)-modified P(AM-co-AA) (acrylamide-co-acrylic acid copolymer) hydrogels. The ionic crosslinking for the double-network P(AM-co-AA)/HACC hydrogels was achieved by an immersion method with Fe³⁺ as crosslinking sites, which crosslinked with the amino group (-NH₂) on HACC and the carboxyl group (-COOH) on P(AM-co-AA) and enabled the hydrogels to recover and reorganize rapidly, resulting in a hydrogel-based strain sensor with excellent tensile stress (3 MPa), elongation (1390%), elastic modulus (0.42 MPa), and toughness (25 MJ/m³). In addition, the prepared hydrogel exhibited high electrical conductivity (21.6 mS/cm) and sensitivity (GF = 5.02 at 0-20% strain, GF = 6.84 at 20-100% strain, and GF = 10.27 at 100-480% strain). Furthermore, the introduction of HACC endowed the hydrogel with excellent antibacterial properties (up to 99.5%) and excellent antibacterial activity against bacteria of three forms, bacilli, cocci, and spores. The flexible, conductive, and antibacterial hydrogel can be applied as a strain sensor for real-time detection of human motions such as joint movement, speech, and respiration, which exhibits a promising application prospect in wearable devices, soft robotic systems, and other fields.

Efficient binding paradigm of protein and polysaccharide: Preparation of isolated soy protein-chitosan quaternary ammonium salt complex system and exploration of its emulsification potential

Soy protein isolate (SPI) has good emulsifying ability, but is greatly affected by the environment. The addition of polysaccharides either increases or decreases the stability of SPI. We report and prepared for the first time SPI/HACC complexes with different polysaccharide contents (SPI/HACC ratios are 1:1, 2:1 and 5:1). The binding properties, microstructure and emulsifying properties of the SPI/HACC complexes were determined and analyzed. The results showed that the interaction them is mainly through hydrogen bonding, electrostatic interaction, hydrophobic interaction and steric hindrance effect. The combination of SPI and HACC overcomes their respective limitations and the microstructure is more flat and smooth. It was also found that the emulsifying ability and concentration of SPI showed a certain correlation and the addition of HACC significantly improved the emulsifying ability and storage stability of SPI. This study shows that the prepared SPI/HACC complex has great potential for application in the food industry.

Converting Acellular Dermal Matrix into On-Demand Versatile Skin Scaffolds by a Balanceable Crosslinking Approach for Integrated Infected Wounds Therapy

Ideal tissue-engineered skin scaffolds should possess integrated therapeutic effects and multifunctionality, such as broad-spectrum antibacterial properties, adjustable mechanical properties, and bionic structure. Acellular dermal matrix (ADM) has been broadly used in many surgical applications as an alternative treatment to the "gold standard" tissue transplantation. However, insufficient broad-spectrum antibacterial and mechanical properties for therapeutic efficacy limit the practical clinical applications of ADM. Herein, a balanceable crosslinking approach based on oxidized 2-hydroxypropyltrimethyl ammonium chloride chitosan (OHTCC) was developed for converting ADM into on-demand versatile skin scaffolds for integrated infected wounds therapy. Comprehensive experiments show that different oxidation degrees of OHTCC have significative influences on the specific origins of OHTCC-crosslinked ADM scaffolds (OHTCC-ADM). OHTCC with an oxidation degree of about 13% could prosperously balance the physiochemical properties, antibacterial functionality, and cytocompatibility of the OHTCC-ADM scaffolds. Owing to the natural features and comprehensive crosslinking effects, the proposed OHTCC-ADM scaffolds possessed the desirable multifunctional properties, including adjustable mechanical, degradable characteristics, and thermal stability. In vitro/in vivo biostudies indicated that OHTCC-ADM scaffolds own well-pleasing broad-spectrum antibacterial performances and play effectively therapeutic roles in treating infection, inhibiting inflammation, promoting angiogenesis, and promoting collagen deposition to enhance the infected wound healing. This study proposes a facile balanceable crosslinking approach for the design of ADM-based versatile skin scaffolds for integrated infected wounds therapy.

Hydroxypropyltrimethyl Ammonium Chloride Chitosan Nanoparticles Coatings for Reinforcement and Concomitant Inhibition of Anionic Water-Sensitive Dyes Migration on Fragile Paper Documents

The fragile paper is treated to improve the stability and appearance of the paper artifact, such as washing, lining, deacidification, and reinforcement. During the above treatments, paper documents inevitably make contact with water directly, leading to the appearance change, stability decrease, and migration or fading of anionic water-sensitive dyes, which are seriously harmful to information security. Herein, Hydroxypropyltrimethyl ammonium chloride chitosan (HACC) nanoparticles were employed for the reinforcement and concomitant inhibition of anionic water-sensitive dye migration on fragile paper. HACC nanoparticles were prepared through physical ball grinding method and characterized via LPSA, SEM, TEM, XRD and FTIR. To evaluate the protective potential of HACC nanoparticles coating, the chemical and mechanical properties of coated and uncoated papers were evaluated after dry heat and hygrothermal accelerated aging. Additionally, good color stability of anionic water-sensitive dyes was observed on the paper coated with HACC nanoparticles after lining technology. Finally, the interaction mechanism between the anionic water-sensitive dyes and HACC nanoparticles was analyzed using an ultraviolet spectrophotometer and FTIR. The as-proposed technique can provide technical support to improve the mechanical properties of fragile paper and enhance the anionic water-sensitive dyes stability in the aqueous phase.

The role of aldehyde-functionalized crosslinkers on the property of chitosan hydrogels

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N-Alkylated chitosan coupled to the liquid-phase polymer-based retention (LPR) technique to remove arsenic (V) from aqueous systems

Water-soluble polymer based on alkylated chitosan with a quaternary ammonium group (Ch-QAG) was prepared, characterized, and applied to remove arsenate ions from aqueous solution by LPR technique. The arsenic removal was performed by the washing method (WM) and enrichment method (EM). Through the WM, studies of the pH and variation in the concentrations of interferents and arsenate ions were carried out. The effect of the removal of arsenate ions in simulated water was determined from the Camarones River in northern Chile. Ch-QAG showed high affinity for binding arsenate species (99% of removal) at pH 11.0 at a molar ratio of 20:1 polymer: As(V). High selectivity was also observed in the presence of interfering ions such as Cl^-, SO₄^2-, and PO₄^3-, resulting in a removal rate over 80% at percentages over 95% for a concentration of 100 mg L^-1 of As (V). The maximum retention capacity obtained was 112, 105, and 98 mg g^-1 for three load cycles. The retention percentage for simulated water was 46.3% at a concentration of 1300 μ g L^-1. In conclusion, the results presented in this study show that using Ch-QAG with ultrafiltration membranes is a great alternative to remove As (V) at high removal rates.

Chitosan and its Derivatives for Ocular Delivery Formulations: Recent Advances and Developments

Chitosan (CS) is a hemi-synthetic cationic linear polysaccharide produced by the deacetylation of chitin. CS is non-toxic, highly biocompatible, and biodegradable, and it has a low immunogenicity. Additionally, CS has inherent antibacterial properties and a mucoadhesive character and can disrupt epithelial tight junctions, thus acting as a permeability enhancer. As such, CS and its derivatives are well-suited for the challenging field of ocular drug delivery. In the present review article, we will discuss the properties of CS that contribute to its successful application in ocular delivery before reviewing the latest advances in the use of CS for the development of novel ophthalmic delivery systems. Colloidal nanocarriers (nanoparticles, micelles, liposomes) will be presented, followed by CS gels and lenses and ocular inserts. Finally, instances of CS coatings, aiming at conferring mucoadhesiveness to other matrixes, will be presented.

Chitosan Derivatives with Mucoadhesive and Antimicrobial Properties for Simultaneous Nanoencapsulation and Extended Ocular Release Formulations of Dexamethasone and Chloramphenicol Drugs

The aim of this work was to evaluate the effectiveness of neat chitosan (CS) and its derivatives with 2-acrylamido-2-methyl-1-propanesulfonic acid (AAMPS) and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (MEDSP) as appropriate nanocarriers for the simultaneous ocular administration of dexamethasone sodium phosphate (DxP) and chloramphenicol (CHL). The derivatives CS-AAMPS and CS-MEDSP have been synthesized by free-radical polymerization and their structure has been proved by Fourier-Transformed Infrared Spectroscopy (FT-IR) spectroscopy. Both derivatives exhibited low cytotoxicity, enhanced mucoadhesive properties and antimicrobial activity against Staphylococcus aureus (S.aureus) and Escherichia coli (E. coli). Encapsulation was performed via ionic crosslinking gelation using sodium tripolyphosphate (TPP) as the crosslinking agent. Dynamic light scattering measurements (DLS) showed that the prepared nanoparticles had bimodal distribution and sizes ranging from 50–200 nm and 300–800 nm. Drugs were encapsulated in their crystalline (CHL) or amorphous (DexSP) form inside nanoparticles and their release rate was dependent on the used polymer. The CHL dissolution rate was substantially enhanced compared to the neat drug and the release time was extended up to 7 days. The release rate of DexSP was much faster than that of CHL and was prolonged up to 3 days. Drug release modeling unveiled that diffusion is the main release mechanism for both drugs. Both prepared derivatives and their drug-loaded nanoparticles could be used for extended and simultaneous ocular release formulations of DexSP and CHL drugs.

Synthesis of cationic quaternized pullulan derivatives for miRNA delivery

Pullulan is a natural polysaccharide of potential interest for biomedical applications due to its non-toxic, non-immunogenic and biodegradable properties. The aim of this work was to synthesize cationic pullulan derivatives able to form complexes with microRNAs (miRNAs) driven by electrostatic interaction (polyplexes). Quaternized ammonium groups were linked to pullulan backbone by adding the reactive glycidyltrimethylammonium chloride (GTMAC). The presence of these cationic groups within the pullulan was confirmed by elemental analysis, Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (¹H NMR). The alkylated pullulan was able to interact with miRNA and form stable polyplexes that were characterized regarding size, zeta potential and morphology. The presence of miRNA was confirmed by agarose gel electrophoresis and UV spectrophotometry. In vitro tests on human umbilical vein endothelial cells did not show any cytotoxicity after 1 day of incubation with nanosized polyplexes up to 200 µg/mL. QA-pullulan was able to promote miRNA delivery inside cells as demonstrated by fluorescence microscopy images of labelled miRNA. In conclusion, the formation of polyplexes using cationic derivatives of pullulan with miRNA provided an easy and versatile method for polysaccharide nanoparticle production in aqueous media and could be a new promising platform for gene delivery.

Homogeneous Synthesis of Cationic Chitosan via New Avenue

Using a solvent formed of alkali and urea, chitosan was successfully dissolved in a new solvent via the freezing⁻thawing process. Subsequently, quaternized chitosan (QC) was synthesized using 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) as the cationic reagent under different incubation times and temperatures in a homogeneous system. QCs cannot be synthesized at temperatures above 60 °C, as gel formation will occur. The structure and properties of the prepared QC were characterized and quaternary groups were comfirmed to be successfully incorporated onto chitosan backbones. The degree of substitution (DS) ranged from 16.5% to 46.8% and the yields ranged from 32.6% to 89.7%, which can be adjusted by changing the molar ratio of the chitosan unit to CHPTAC and the reaction time. QCs inhibits the growth of Alicyclobacillus acidoterrestris effectively. Thus, this work offers a simple and green method of functionalizing chitosan and producing quaternized chitosan with an antibacterial effect for potential applications in the food industry.

Preparation of chitin-amphipathic anion/quaternary ammonium salt ecofriendly dressing and its effect on wound healing in mice

Objective

This study aimed to prepare an eco-friendly dressing using a chitin-derived membrane with amphipathic anion/quaternary ammonium salt designed for antibacterial purposes.

Methods

Four dressings were prepared and group A was chitin, group B was chitin + amphiphilic ion, group C was chitin + quaternary ammonium salt, group D was chitin + amphiphilic ion + quaternary ammonium salt.

Results

In the group D material, precipitation of adherent composite ions was observed. The contact angle test showed that the material was hydrophilic. The drug loading rate in groups B, C, and D was 40-50 (ug:mg), the entrapment efficiency was 70%-75% (P>0.05), and the cumulative release percentages were 87.3%, 88.7%, and 90.2% after 72h for group B, C, and D, respectively. The anti-bacterial activity in vitro was in the order D>C>B>A> control (P>0.05). The anti-pollution activity in vitro was in the order D>B>C>A (P<0.05). The cell proliferation inhibition test showed slight proliferation inhibition (P<0.05) only on the seventh day for group D. Seven days after injury, the wound healing rate was in the order D>C> commercial chitin dressing >B>A> control (P<0.05), and the length of the neonatal epithelium also showed the same trend. Additionally, PCNA and CD31 expression indicated that cell proliferation and angiogenesis were enhanced when skin defects were covered with the D group material (P<0.05).

Conclusion

chitin-amphiphilic ion/quaternary ammonium salt dressing was successfully prepared. The antibacterial and antipollution effects of the prepared material (group D) were both very good, acting to promote wound healing.

Acitretin modulates HaCaT cells proliferation through STAT1- and STAT3-dependent signaling

Acitretin has been a valuable option for the treatment of psoriasis, however, the molecular events of acitretin leading to the normalization of keratinocytes differentiation on psoriasis patients have not been fully explored. To investigate whether there were certain relationship between keratinocytes proliferation and JAK/STAT signaling pathways in psoriasis, and how acitretin modulated the signaling pathways. HaCaT cells, an in vitro immortal human keratinocyte cell line, was chosen as a in vitro model of psoriasis. The small interfering RNA targeting STAT1 (siRNA-STAT1) and STAT3 (siRNA-STAT3) were subsequently transfected into the HaCaT cells which were treated with or without acitretin. We found that HaCaT cells proliferation and the expression of STAT1 or STAT3 were inhibited by acitretin, siRNA-STAT1 and siRNA-STAT3. Our experimental data shows that acitretin might inhibit HaCaT cells proliferation in psoriasis by decreasing the expression of STAT- and STAT3-dependent mechanism.

The comparative study of clinical efficacy and safety of baclofen vs tolperisone in spasticity caused by spinal cord injury

In the present study we compared the clinical efficacy and safety of baclofen vs tolperisone in spasticity caused by spinal cord injury. A total of 150 patients were enrolled in the present study and were divided into two groups with 75 patients in each group, receiving baclofen or tolperisone, respectively. We used Modified Ashworth Scale, Medical research council scale, Barthel Index, and Coefficient of efficacy to measure clinical efficacy. After 6-week treatment, both groups demonstrated significant improvement in muscle tone, muscle strength and functional outcome (Group I, 1.55 ± 0.053, 2.79 ± 0.032, 59.31 ± 1.32; Group II, 1.57 ± 0.053, 3.04 ± 0.032, 73 ± 1.32 respectively). There was no significant difference regarding improvement in muscle tone and muscle strength between the two groups (Group I, 1.055 ± 0.053 vs Group II, 1.57 ± 0.053; Group I, 2.79 ± 0.032 vs Group II, 3.04 ± 0.032, p > 0.05). However, the improvement in functional outcomes was greater in group II as compared to that in group I (Group I, 59.31 ± 1.32 vs Group II, 73 ± 1.32, p < 0.05). In addition, overall efficacy coefficient was greater for group II as compared to group I (Group I, 3.6 vs Group II, 2.3, p < 0.05). Group I had more side effects compared to Group II. Compared to baclofen, tolperisone offers greater improvement in activities of daily living compared to baclofen.

Imperatorin protects H9c2 cardiomyoblasts cells from hypoxia/reoxygenation-induced injury through activation of ERK signaling pathway

BACKGROUND

Imperatorin is a compound found in plants and has been widely used in Chinese medicine for many years. It has many pharmacological effects, including the recently reported anti-apoptotic function, however, the mechanism largely remains unclear. This study is aimed to elucidate the mechanism of Imperatorin's anti-apoptotic function.

METHODS

A model of hypoxia and reoxygenation (H/R) treated h9c2 cardiomyoblasts was successfully constructed. The cells were treated with H/R condition, and followed by adding Imperatorin alone, Imperatorin with ERK inhibitor and/or ERK inhibitor alone, to examine the cell viability by Cell Counting Kit-8 assay, cell apoptosis rate by flow cytometry, and ERK expression by Western-blot under different conditions.

RESULTS

The results showed that imperatorin exerted protective effect on h9c2 cells from H/R injure. It was also found that it not only increased cell viability but also reduced the apoptotic rate for H/R treated h9c2 cells. The experiments also demonstrated that imperatorin could upregulate the expression levels of both ERK1 and ERK2, which is a key step in ERK signaling pathway activation.

CONCLUSIONS

These findings provided evidence that imperatorin could increase the cell viability and lower apoptotic rate in H/R treated h9c2 cells, and could also enhance the expression of ERK1/ERK2, demonstrating imperatorin's protective effect on H/R injured h9c2 cells through ERK signaling pathway.

The effects of low-molecular-weight heparin on lung and pulmonary artery injuries in acute pulmonary embolism rat model via platelet-derived growth factor-β

Objective

To evaluate the effects of anticoagulant agent (low-molecular-weight heparin, LMWH) on the pulmonary artery intima hyperplasia of rats with acute pulmonary embolism (APE) by assaying platelet-derived growth factor-β (PDGF-β).

Methods

A total of 90 Sprague-Dawley rats were randomly assigned into the sham, APE, and LMWH groups with 30 rats in each group. The APE rat models were established by injecting autologous blood clots via external jugular veins. In each group, six mice were sacrificed at the 1st day (D1), 4th day (D4), 7th day (D7), 14th day (D14), and 28th (D28) subsequent to the induction of APE to collect the lungs. Right ventricle pressure (RVP) and mean pulmonary arterial pressure (mPAP) were measured. Western blot and RT-PCR analyses were used to assess PDGF-β expression at various time points. In addition, changes in lung pathology were evaluated using hematoxylin and eosin (H&E) staining and electron microscope.

Results

The overall success rate of establishing APE rat models was 85.7% (60/70). There was no difference in mPAP between the sham group and the APE group at the D1, D4, D7, and D14. However, at the D28, mPAP in the APE group was significantly higher than that in the sham group. There was no difference among the three groups regarding RVP. PDGF-β expression were decreased in the LMWH group at all time points compared with the sham and APE groups (P < 0.01). Furthermore, pulmonary embolism, alveolar wall necrosis and hemorrhage, and inflammation were significantly attenuated in the LMWH group compared with the sham and APE groups subsequent to the induction of APE.

Conclusion

LMWH attenuates lung and pulmonary artery injuries and improves prognosis. Decreased PDGF-β in the lungs may be the important factor in the effects observed.

The influence of connective tissue growth factor on rabbit ligament injury repair

Objectives

The injured anterior cruciate ligament (ACL) is deemed to exhibit an impaired healing response and attempts at surgical repair have not been successful. Connective tissue growth factor (CTGF) is reported to be associated with wound healing, probably through transforming growth factor beta1 (TGF-β1).

Methods

A rabbit ACL injury model was used to study the effect of CTGF on ligament recovery. Quantitative real-time PCR was performed for detection of changes in RNA levels of TGF-β1, type 1 collagen (COL-I), type 2 collagen (COL-II), SRY-related high mobility group-box gene9 (Sox9), metalloproteinase-1 (TIMP-1) as well as matrix metallopeptidase 13 (MMP-13). And expression of related proteins was detected by western blotting.

Results

The current study showed that CTGF could promote the recovery of inured anterior cruciate ligament. It can up-regulate the mRNA and expression of TGF-β1, COL-I, COL-II, Sox9, as well as the tissue inhibitor of TIMP-1, and down-regulated the mRNA and expression of MMP-13, suggesting the curative effect of CTGF on injured rabbit ligament is through regulating these cellular factors.

Conclusion

This finding revealed the mechanism of CTFG’s healing role in injured tissues and provided new possibilities of treating injured tissues and wound healing by using CTFG.

Impacts of triamcinolone acetonide on femoral head chondrocytic structures in lumbosacral plexus block

Objective: To investigate impacts of triamcinolone acetonide (TRI) on femoral head chondrocytic (FHC) structures when used for lumbosacral plexus block (LPB). Methods: A total of 32 6-month-old New Zealand white rabbits were selected (averagely weighing 2.75–3.25 kg) and added TRI into nerve block solution for LPB. The rabbit were randomly divided into four groups: group A1: 2.5 ml × 2 times, group A2 2.5 ml × 4 times, group B1 5 ml × 2 times, and group B2 5 ml × 4 times; the time interval among the injection was 5 days, and the structural changes of FHC were the observed using 50/100/200 light microscope; the modified Mankin pathological scoring was also performed for the evaluation. Results: There exhibited significant microscopic changes of FHC structures between the rabbits performed LPB and the normal rabbits, among which group B2 exhibited the most serious FHC damages, and the Mankin pathological score in group B2 was much higher than those in the other three groups, and the scores of the experimental group were higher than the control group. Conclusions: The addition of TRI in LPB can damage the FHC structures, and large-dose (5 ml/once) and long-course (four times) will result in more serious injuries.

Investigation on the immunomodulatory activities of Sarcodon imbricatus extracts in a cyclophosphamide (CTX)-induced immunosuppressanted mouse model

Aims: Sarcodon imbricatus, an edible fungus, is widely used in Asian medicine because of its significant pharmacological activities. In the present study, we investigated the immunomodulatory effects of polysaccharide-enriched S. imbricatus extracts (SP) in cyclophosphamide (CTX)-induced immunosuppressed mice. Results: Astragalus polysaccharide (AP) was used as a positive control. Compared with CTX-induced immunosuppressed mice, thirty-day SP treatment strongly enhanced the organ indexes of spleen and thymus and suppressed hind paw swelling. Both AP and SP increased the serum levels of immunoglobulin (IgA, IgG, and IgM), and suppressed the overproduction of interleukin-2 (IL-2). Moreover, SP reduced methane dicarboxylic aldehyde levels, and increased the total antioxidant capacity, superoxide dismutase, and glutathione peroxidase in both serum and liver tissues of CTX-induced immunosuppressed mice. Conclusion: S. imbricatus extracts significantly improved immune function in CTX-induced immunosuppressed mice via modulation of oxidative systems.