Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis

AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web of Science,Cochrane,SinoMed,CNKI,Wanfang Database,CQVIP,and Chinese journals databases between inception and July 2023.Pooled standardized mean differences(SMD)or weighted mean difference(WMD)with 95%confidence intervals(CI)from RCTs evaluating Schirmer’s I test(SIT),corneal fluorescein staining score(CFS),tear breakup time(TBUT),DES score(DESS),and Ocular Surface Disease Index(OSDI)were calculated.Sensitivity analysis,Egger’s test and Meta-regression analysis were performed for all indicators.RESULTS:We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria,involving 1796 cases.High-concentrations group significantly improved the outcome of CFS according to random effects modelling(SMD,-3.37;95%CI,-5.25 to-1.48;P=0.0005).The rest of the results were not statistically significant,including indicators such as SIT,TBUT,DESS and OSDI.CONCLUSION:For dry eyes with positive corneal staining,a high concentration of HY is recommended,whereas in other cases,a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes.

A multi-functional MgF_(2)/polydopamine/hyaluronan-astaxanthin coating on the biodegradable ZE21B alloy with better corrosion resistance and biocompatibility for cardiovascular application

The cardiovascular diseases(CVD)continue to be the major threat to global public health over the years,while one of the effective methods to treat CVD is stent intervention.Biomedical magnesium(Mg)alloys have great potential applications in cardiovascular stents benefit from their excellent biodegradability and absorbability.However,excessive degradation rate and the delayed surface endothelialization still limit their further application.In this study,we modified a Mg-Zn-Y-Nd alloy(ZE21B)by preparing MgF_(2) as the corrosion resistance layer,the dopamine polymer film(PDA)as the bonding layer,and hyaluronic acid(HA)loaded astaxanthin(ASTA)as an important layer to directing the cardiovascular cells fate.The electrochemical test results showed that the MgF_(2)/PDA/HA-ASTA coating improved the corrosion resistance of ZE21B.The cytocompatibility experiments also demonstrated that this novel composite coating also selectively promoted endothelial cells proliferation,inhibited hyperproliferation of smooth muscle cells and adhesion of macrophages.Compared with the HAloaded rapamycin(RAPA)coating,our MgF_(2)/PDA/HA-ASTA coating showed better blood compatibility and cytocompatibility,indicating stronger multi-functions for the ZE21B alloy on cardiovascular application.

Effect of sodium hyaluronate combined with rehabilitation training on knee joint injury caused by golf

BACKGROUND In high-intensity sports like golf,knee joints are prone to injury,leading to pain,limited mobility,and decreased quality of life.Traditional treatment methods typically involve rehabilitation exercises,but their effectiveness may be limited.In recent years,sodium hyaluronate has emerged as a widely used biomedical material in the treatment of joint diseases.AIM To explore the effect of sodium hyaluronate combined with rehabilitation training on pain degree,flexion range of motion and motor function of knee joint injured by golf.METHODS Eighty patients with knee joint injury caused by golf were randomly divided into control(group B)and observation group(group A).The group B was treated with rehabilitation training,and the group A was treated with sodium hyaluronate combined with rehabilitation training.The clinical efficacy,range of motion and function of knee joint,quality of life and inflammatory factors were compared.RESULTS The excellent and good rate of rehabilitation in the group A was raised than group B.At 6 weeks and 3 months after treatment,the range of motion of the two groups was raised than that before treatment,and that of the group A was raised than group B.After treatment,the scores of Lysholm and International Knee Documentation Committee(IKDC)in the group A were raised,and those in the group A were raised than group B.The VAS score of the two groups was reduced than that of the group B,and the SF-36 score of the group A was reduced than group B.The interleukin(IL)-1β,IL-8 and tumor necrosis factor-αin the two groups were reduced,and those in the group A were reduced than group B.CONCLUSION Sodium hyaluronate combined with rehabilitation training has a good clinical effect in the treatment of patients with knee joint injury caused by golf,which relieve pain,maintain knee joint function and improve patients'life quality.

Impacts of mesenchymal stem cells and hyaluronic acid on inflammatory indicators and antioxidant defense in experimental ankle osteoarthritis

BACKGROUND No effective treatment guarantees full recovery from osteoarthritis(OA),and few therapies have disadvantages.AIM To determine if bone marrow mesenchymal stem cells(BMMSCs)and hyaluronic acid(HA)treat ankle OA in Wistar rats.METHODS BMMSCs were characterized using flow cytometry with detection of surface markers[cluster of differentiation 90(CD90),CD105,CD34,and CD45].Fifty male Wistar rats were divided into five groups of 10 rats each:Group I,saline into the right tibiotarsal joint for 2 days;Group II,monosodium iodate(MIA)into the same joint;Groups III,MIA+BMMSCs;Group IV,MIA+HA;and Group V,MIA+BMMSCs+HA.BMMSCs(1×106 cells/rat),HA(75μg/rat),and BMMSCs(1×106 cells/rat)alongside HA(75μg/rat)were injected intra-articularly into the tibiotarsal joint of the right hind leg at the end of weeks 2,3,and 4 after the MIA injection.RESULTS The elevated right hind leg circumference values in the paw and arthritis clinical score of osteoarthritic rats were significantly ameliorated at weeks 4,5,and 6.Lipid peroxide significantly increased in the serum of osteoarthritic rats,whereas reduced serum glutathione and glutathione transferase levels were decreased.BMMSCs and HA significantly improved OA.The significantly elevated ankle matrix metalloproteinase 13(MMP-13)mRNA and transforming growth factor beta 1(TGF-β1)protein expression,and tumor necrosis factor alpha(TNF-α)and interleukin-17(IL-17)serum levels in osteoarthritic rats were significantly downregulated by BMMSCs and HA.The effects of BMMSCs and HA on serum TNF-αand IL-17 were more potent than their combination.The lowered serum IL-4 levels in osteoarthritic rats were significantly upregulated by BMMSCs and HA.Additionally,BMMSCs and HA caused a steady decrease in joint injury and cartilage degradation.CONCLUSION BMMSCs and/or HA have anti-arthritic effects mediated by antioxidant and anti-inflammatory effects on MIAinduced OA.MMP-13 and TGF-β1 expression improves BMMSCs and/or HA effects on OA in Wistar rats.

Intra-articular interventions in osteoarthritis:Navigating the landscape of hyaluronic acid,mesenchymal stem cells,and plateletrich plasma

Osteoarthritis(OA)poses a substantial burden on patients,leading to pain,functional decline,and reduced quality of life.While conventional treatments focus on symptom management,disease-modifying interventions are yet to be established.This review explores the efficacy of intra-articular interventions,particularly hyaluronic acid(HA),mesenchymal stem cells(MSCs),and platelet-rich plasma(PRP),in the context of OA management.HA injections,with diverse formulations like Hylan G-F20,sodium hyaluronate,and hyaluronan,present varying outcomes,necessitating a nuanced understanding of their effectiveness and timing.MSC therapy,derived from adipose tissue,umbilical cord,or bone marrow,shows promising results in clinical improvement,with adipose-derived MSCs demonstrating efficacy in maintaining benefits over 6 mo.Conversely,bone-marrow-derived MSCs show limited effectiveness,highlighting the need for sourcespecific considerations.PRP has emerged as a superior option for long-term pain reduction and quality of life improvement,with leukocyte-poor formulations and a critical platelet count of 10 billion demonstrating optimal results.This comprehensive analysis underscores the potential of intra-articular interventions in OA management,emphasizing the need for personalized and evidence-based approaches to enhance treatment efficacy and patient outcomes.

Efficacy of recombinant human epidermal growth factor plus sodium hyaluronate eye drops in diabetic dry eye post-cataract surgery

BACKGROUND Dry eye syndrome(DES)after diabetic cataract surgery can seriously affect the patient’s quality of life.Therefore,effective alleviation of symptoms in patients with this disease has important clinical significance.AIM To explore the clinical effect of recombinant human epidermal growth factor(rhEGF)plus sodium hyaluronate(SH)eye drops on DES after cataract surgery in patients with diabetes.METHODS We retrospectively evaluated 82 patients with diabetes who experienced DES after cataract surgery at Tianjin Beichen Hospital,Affiliated Hospital of Nankai University between April 2021 and April 2023.They were classified into an observation group(42 cases,rhEGF+SH eye drops)and a control group(40 cases,SH eye drops alone),depending on the different treatment schemes.The therapeutic efficacy,dry eye symptom score,tear film breakup time(TFBUT),basic tear secretion score[assessed using Schirmer I test(SIt)],corneal fluorescein staining(FL)score,tear inflammatory markers,adverse reactions during treat-ment,and treatment satisfaction were compared between the two groups.RESULTS Therapeutic efficacy was higher in the observation group compared with the control group.Both groups showed improved TFBUT and dry eye,as well as improved SIt and FL scores after treatment,with a more pronounced improvement in the observation group.Although no marked differences in adverse reactions were observed between the two groups,treatment satisfaction was higher in the observation group.CONCLUSION rhEGF+SH eye drops rendered clinical benefits to patients by effectively ameliorating dry eye and visual impairment with favorable efficacy,fewer adverse reactions,and high safety levels.Thus,this treatment should be promoted in clinical practice.

Purification and Characterization of Hyaluronate Lyases Produced by Two Types of Bacteria

Hyaluronate lyases were obtained from two types of naturally isolated bacterial strains Paenibacillus yunnanensis and Paennarthrobacter nicotinovorans.PyHL(form P.yunnanensis)in the culture supernatant of the bacteria was purified by two steps of column chromatography.The enzyme showed the molecular mass of 74 kDa by SDS-PAGE and the maximal activity at pH 5.0,35℃.PyHL maximally degraded hyaluronate by an endo-type manner,and showed low degradation activity toward chondroitin sulfates.Dermatan sulfate was not the substrate.PnHL(from P.nicotinovorans)in the culture supernatant of the bacteria was purified by two steps of column chromatography.The enzyme showed the molecular mass of 70 kDa by SDS-PAGE and the maximal activity at pH 6.0,30℃.Genomic analysis of P.nicotinovorans on the bases of the internal amino acid sequences of PnHL.

A hyaluronic acid granular hydrogel nerve guidance conduit promotes regeneration and functional recovery of injured sciatic nerves in rats

A hyaluronic acid granular hydrogel can promote neuronal and astrocyte colony formation and axonal extension in vitro,suggesting that the hydrogel can simulate an extracellular matrix structure to promote neural regeneration.However,in vivo experiments have not been conducted.In this study,we transplanted a hyaluronic acid granular hydrogel nerve guidance conduit to repair a 10-mm long sciatic nerve gap.The Basso,Beattie,and Bresnahan locomotor rating scale,sciatic nerve compound muscle action potential recording,Fluoro-Gold retrograde tracing,growth related protein 43/S100 immunofluorescence staining,transmission electron microscopy,gastrocnemius muscle dry/wet weight ratio,and Masson’s trichrome staining results showed that the nerve guidance conduit exhibited similar regeneration of sciatic nerve axons and myelin sheath,and recovery of the electrophysiological function and motor function as autologous nerve transplantation.The conduit results were superior to those of a bulk hydrogel or silicone tube transplant.These findings suggest that tissue-engineered nerve conduits containing hyaluronic acid granular hydrogels effectively promote the morphological and functional recovery of the injured sciatic nerve.The nerve conduits have the potential as a material for repairing peripheral nerve defects.

Hyaluronic acid injection in the auricular base for the aesthetic correction of lying ears:A retrospective study

Background Ears play an important role in facial profiles.Lying ears are not perceived favorably in Asian cultures;therefore,surgical procedures are implemented to adjust this defect.However,surgery has complications and requires recovery time.We introduced a hyaluronic acid(HA)injection technique to aesthetically improve ear prominence.Methods This retrospective study examined 25 Chinese patients aged 20-47 years with congenital lying ears who received HA injections in the auricular base at Shanghai Ninth People’s Hospital and Hangzhou Yijie Medical Cosmetology Clinic between November 2019 and December 2022.The average injection volume was 6.32±1.22 mL in the auricular base unilaterally,and the follow-up time ranged from 6 to 24 months.Morphological measurement data were recorded.Two-dimensional(2D)and three-dimensional(3D)images were obtained to evaluate the effects.Results All patients showed improvements in ear prominence.The cranioauricular angle(CAA)increased from 22.24°±4.53°to 65.90°±5.38°immediately post-injection and was maintained at 49.18°±4.74°6 months later.The ear projection(EP)increased from 14.75±2.72 mm to 26.26±2.94 mm immediately post-injection and was 22.51±2.68 mm after 6 months.No serious complications were noted.Conclusion HA injection in the auricular base effectively corrected the lying ears and aesthetically optimized the facial profile.It also had a face-lift effect that made the face look younger and more compact.The injection procedure was minimally invasive and required no recovery period.The effect was maintained for a long time and was satisfactory.

Development of hyaluronic acid-based edible film for alleviating dry mouth

For alleviating dry mouth symptoms,edible films based on hyaluronic acid(HA)with 3 different m(800,1200 and 2300 kDa)were prepared(800 F,1200 F and 2300 F,respectively),and the properties as well as effectiveness were compared.The concentration of each HA dispersion for film forming was set as 3.0%,1.5%or 1.0%,for the m800,1200 and 2300 kDa,respectively,based on the solubility.The 800 F showed the highest thickness,tensile strength,and water vapor transparency,whereas obtained the lowest transparency and elongation at break among samples.All of the HA films showed safety against microorganism during 28 storage day at 40℃with 60%humidity.The optimum site for film attachment in mouth was the palate,and800 F was the most effective for stimulating saliva secretion,eliciting a 38%increase compared to control(without film),tested by the elderly over 65 years old.By the sensory test,800 F was also the most acceptable.Based on above results,the edible films effectively stimulating saliva secretion could be produced with HA,and the physical,sensory characteristics as well as disintegration times of the film could be controlled by mand the dissolution concentration of HA.

A Comprehensive Review of Long-Term Safety and Effectiveness of FACILLE Modified Sodium Hyaluronate Gel for Injection over 3 Years

FACILLE modified sodium hyaluronate gel was designed to be used for nasolabial fold (NLF) correction. However, no study has investigated the long-term safety and effectiveness of FACILLE. Thus, a retrospective study of 14 aesthetic clinics in China was conducted. This was the first large-scale, postmarketing study on FACILLE to evaluate the occurrence of adverse events (AEs) and provide essential information on the satisfaction of patients with FACILLE injections. This study recruited participants aged >18 years. FACILLE was injected into the NLFs on both sides of each participant’s face. The primary endpoint for safety was systemic or severe AEs at an injection site. Effectiveness was assessed on the basis of the participants’ subjective perceptions and satisfaction levels. Safety and effectiveness data were collected on the day of injection and at 2 weeks and 1, 3, 6, 9, 12, 18, 24, 30 and 36 months postinjection. In total, 1552 participants were enrolled (mean age, 29.1 years), and most of them (96.5%) were women. The mean injection volume was 1.39 ± 0.658 mL, and the average number of injections was 2.4 ± 1.68. AEs were reported by 205 participants (13.2%). All AEs occurred at local injection sites. No systemic or severe AEs were observed. Local pain was the most frequently reported AE regardless of the number of injections or the injection volume. Only eight AE cases were correlated with FACILLE administration, with two cases involving local allergic reactions. The participants self-reported that they perceived the procedure to have an effectiveness of ≥90% within 6 months postinjection although this percentage decreased substantially after 9 months. Their satisfaction level was >90% within 1 month postinjection but decreased gradually after 3 months. Our results indicate that the long-term safety of FACILLE injection is adequate. The high self-reported perceived effectiveness and satisfaction levels indicate the considerable potential of FACILLE injections for correcting NLFs.

Exposure to Hyaluronan and Radon-Containing Water during the Treatment of Periodontal Pockets

Hyaluronic acid (HA) preparations have emerged as pivotal components in contemporary dentistry, gaining widespread recognition for their multifaceted roles in various biological functions. Extensive literature underscores the significance of HA in maintaining tissue water balance, fostering cell proliferation, promoting rapid cell migration, influencing cell differentiation during organism development, and facilitating tissue regeneration. Notably, HA’s interactions with cell surface receptors contribute to the viscosity of synovial fluid, activate the immune system, and enhance cartilage elasticity. Beyond these established functions, HA has also been investigated for its potential involvement in determining and studying the hormetic effects of radon water, adding a novel dimension to its applications in dental research. A thorough exploration of existing studies reveals a nuanced understanding of how HA interventions impact the outcomes of dental procedures. The comprehensive scope of these investigations allows for a more accurate assessment of the potential effectiveness of specific interventions and provides valuable insights into post-procedural prognoses for individual patients. This synthesis of literature serves as the foundation for elucidating the intricate interplay between HA, radon exposure, and their relevance in modern dental practices.

Design of Novel Wound Dressing Composed of Collagen and Hyaluronic Acid Containing Epidermal Growth Factor

This research aims to develop a wound dressing composed of collagen (Col) and hyaluronic acid (HA) containing epidermal growth factor (EGF). First important issue is to contain EGF in the wound dressing in a stable state. The sheet-shaped sponge was manufactured by freeze-vacuum drying an aqueous solution of Col. Both sides of sponge were treated with ultraviolet (UV) irradiation to introduce intermolecular cross links between collagen molecules. This sponge was named Sponge-Col. Another sheet-shaped sponge was manufactured by freeze-vacuum drying an aqueous solution of HA containing EGF. This sponge was named Sponge-HA/EGF. The wound dressing was manufactured by laminating Sponge-Col on the top, Sponge-HA/EGF in the middle, and Sponge-Col on the bottom to create a sandwich structure. This method can prevent the reducing of EGF activity due to UV irradiation for intermolecular cross-linking. Second important issue is to enable gradual release of EGF from the wound dressing. The elution behavior of this wound dressing was investigated by measuring the weight change after immersion in water for a predetermined time. This wound dressing showed initially fast elution and subsequent very slow elution properties. The upper layer and lower layer Sponge-Col enabled gradual release of the middle layer Sponge-HA/EGF. This result suggests that EGF contained in the wound dressing is gradually released together with HA from the wound dressing. Third important issue is to provide moist wound-healing environment. The upper layer and lower layer Sponge-Col can provide the wound dressing with high water absorption and long-term water retention properties.

The Value of the Measurement of Urinary Hyaluronic Acid Levels for the Diagnosis of Bladder Cancer

Objective To investigate the value of the measurement of urinary hyaluronic acid (HA) levels for the diagnosis of bladder cancer and the possibility of replacing ELISA-like assay with radioimmunoassay to detect the levels of urinary HA. Methods Using the ELISA-like assay and radioimmunoassay at the same time to measure the HA levels in the urine specimens from 49 bladder cancer patients, 12 benign bladder tumor patients, 30 other genitourinary disease patients and 20 normal controls. Results There is not much difference between the consequences of the urinary HA levels whether we used the ELISA-like assay or radioimmunoassay to detect every specimen (P>0.05). When we used the results with radioimmunoassay for analysis, we found the levels of urinary HA of bladder cancer patients were 2–4 times than those of the benign bladder tumor patients, other genitourinary disease patients or normal individuals (P<0.01); With 137.5 ngHA/mg protein (113.6±23.9 ng/mg) as a minimum cutoff limit, this assay had a good sensitivity (91.8%) and specificity (91.9%) for the diagnosis of bladder cancer. Its difference in sensitivity meant a lot when compared with urine cytology (48.9%,P<0.01). Conclusion The urinary HA assay is a simple, convenient, noninvasive credible and cheap method with satisfactory sensitivity and specificity for the diagnosis of bladder carcinoma; radioimmunoassay is also a good means to measure the urinary HA levels. Key words Bladder carcinoma - Hyaluronic acid - Urine

Determination of sodium hyaluronate in pharmaceutical formulations by HPLC–UV

A liquid chromatography （HPLC） method with UV detection was developed for determination of sodium hyaluronate in pharmaceutical formulation. Sodium hyaluronate is a polymer of disaccharides, composed of D-glucuronic acid and D-N-acetylglucosamine, linked via alternating 13-1, 4 and D-l, 3 glycosidic bonds. Being a polymer compound it lacks a UV absorbing chromophore. In the absence of a UV absorbing chromophore and highly polar nature of compound, the analysis becomes a major challenge. To overcome these problems a novel method for the determination of sodium hyaluronate was developed and validated based on size exclusion liquid chromatography （SEC） with UV detection. An isocratic mobile phase consisting of buffer 0.05 M potassium dihydrogen phosphate, pH adjusted to 7.0 using potassium hydroxide （10%） was used. Chromatography was carried out at 25 ~C on a BioSep SEC $2000, 300 mm ~ 7.8 mm column. The detection was carded out using variable wavelength UV-vis detector set at 205 nm. The compounds were eluted isocratically at a steady flow rate of 1.0 mL/min. Sodium hyaluronate retention time was about 4.9 min with an asymmetry factor of 1.93. A calibration curve was obtained from 1 to 38 g/mL （r〉0.9998）. Within-day % RSD was 1.0 and between-day % RSD was 1.10. Specificity/selectivity experiments revealed the absence of interference from excipients, recovery from spiked samples for sodium hyaluronate was 99-102. The developed method was applied to the determination of sodium hyaluronate in pharmaceutical drug substance and product.

Correlation Between Hyaluronic Acid,Hyaluronic Acid Synthase And Human Renal Clear Cell Carcinoma

Objective：To study the correlation between hyaluronic acid（HA）,hyaluronic acid synthase（HAS） and human renal clear cell carcinoma（RCCC）.Methods：The expression of three HAS isoforms＇ gene and HA in 93 RCCC tissues,27 nephridial tissues by the side of RCCC from two hospitals were measured with Real-Time RT-PCR、Western Blot and immunohistochemical methods and analyzed.Results：All RCCC and adjacent normal tissues expressed three HASs＇ mRNA protein;at the mRNA level,both RCCC and adjacent normal tissues,expressed more HAS3 than HAS1 or HAS2,their differences were statistically significant（all P values 0.05）;but,at the protein level,all HAS isoforms presented the equivalent expression.Compared with the adjacent non-neoplastic kidney tissues,the expression of all HAS isoforms＇ mRNA in RCCC tissues were increased evidently and their differences were significant（all P values 0.0001）;but at the protein level,only the expression of HAS3 increased evidently（P=0.022）.In all adjacent normal tissues,more than 80% renal tubular cells strongly expressed HA,however,only the minority RCCC cases（16/93） presented weakly positive HA staining in few cancer nests（5%-30%）,the difference were significant（P0.0001）.In RCCC tissues subgrouped according to clinical stage,pathological grade,lymphatic metastasis or not and distant metastasis or not,the HASs＇ mRNA protein differential expression all had no statistical significance（all P values 0.05）.Conclusion：Different from other malignancy,HA and HASs（except for HAS3） may not play important roles in the biological progress of human RCCC.

In vitro anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe grade black tea(Camellia sinensis L.)

Objective:To access the anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe（OP） grade black tea with a view to develop an anti-aging skin formulation.Methods:Five concentrations（0.125,0.250,0.500,1.000 and 2.000 mg/mL） of black tea brew（BTB） were made using a freeze dried sample of Sri Lankan low grown orthodox OP grade black tea which was prepared according to international organization for standardization specification.Epigallocatechin gallate（EGCG） was used as the reference agent（concentrations tested:0.012,0.025,0.050,0.100 and 0.200 mg/mL）.Anti-hyaluronidase activity of BTB and EGCG in vitro were ascertained spectrometrically using hyaluronic acid（from rooster comb）and bovine testicular hyaluronidase.Results:The results revealed that BTB had moderate[IC50=（1.09±0.12） mg/mL]and dose dependent（r2=0.94） anti-hyaluronidase activity.EGCG also exhibited dose dependent（r2=0.93,P【0.05） anti-hyaluronidase activity which was superior[IC50=（0.09±0.00） mg/mL]to BTB.Conclusions:Sri Lankan low grown orthodox OP gradc black tca has promising antihyaluronidase activity in vitro and has the potential to be used as an anti-aging cosmaceutical.In addition,it may prove useful as a beverage in the management of allergy,some joint diseases and cnvenomation.

A Guide to Cheek Augmentation: Single-Point Deep Injection of Hyaluronic Acid Filler at Midface in Close Proximity to Medial Suborbicularis Oculi Fat (SOOF) Area

Loss of volume in midface can result in an aged, wasted appearance. Osseous and fat atrophy with aging may further contribute to the loss of soft tissue support and midface ptosis. In the aging of periorbital area and midface, fat atrophy occurs mostly in the suborbicularis oculi fat (SOOF) area. The authors proposed that injection of hyaluronic acid (HA) filler to support the SOOF area could counteract the aging sign due to fat atrophy, restore volume loss and achieve a more youthful appearance. The authors described the treatment of 10 female patients who received CHAP®-particle hyaluronic acid (CHAP®-HA) injections for cheek augmentation, using single-point deep injection technique at midface in close proximity to SOOF area. Such approach provides satisfactory cheek augmentation results without significant complications. The authors discussed a rationale for their choice of dermal filler and provided an injection technique for restoring volume in the midface region with CHAP®-HA. Such technique is relatively quick to perform, have little down time, and result in a high rate of patient satisfaction.

Therapeutic Use of Hyaluronidase in Obstetrics

Introduction: Hyaluronidases are a group of enzymes that permit greater diffusion of fluid through the tissues. These enzymes have the ability to reduce the viscosity of hyaluronic acid and increase cellular membrane and blood vessel permeability. This review discusses the indication, usage, effects, and safety of hyaluronidases in obstetrics. Materials and Methods: MEDLINE/ PubMed and the Cochrane Library were searched using the following terms: (“hyaluronidase” [Title/Abstract]) OR (“hyaluronidases” [Title/Abstract]) AND (“therapeutic use” [Title/Abstract]) OR (“therapeutic uses” [Title/Abstract]) OR (“perineal trauma” [Title/Abstract]) OR (“perineal tear” [Title/Abstract]) OR (“cervical ripening” [Title/Abstract]). Results: This review included four randomized controlled trials (RCT) that randomized a total of 642 pregnant women and two interventional non-RCTs that included a total of 2824 pregnant women. The data from two RCTs suggested that the incidence of perineal trauma was significantly lower in the intervention (perineal hyaluronidase injection in stage two of labor) than the control group (no intervention). However, both groups did not differ significantly in the incidence of first- and second-degree tears. Similarly, no significant difference in the incidence of episiotomy was found between both groups. In one interventional non-RCT, the administration of intracervical hyaluronidase was associated with a statistically significant acceleration and shortening of labor by approximately 1.95 hours after the injection of intracervical hyaluronidase. However, it had no effect on uterine contractions or the duration of stages two and three labor. Conclusions: While it is safe, clinicians should consider patient acceptance and the effectiveness of hyaluronidase compared to conventional less invasive methods.

Study on Chemical Cross-linking Modification of Hyaluronan and the Biocompatibility of its Derivatives

Objective: Prepare cross-linked HA gels with higher mechanical stability, lower degradation velocity and desirable biocompatibility,so as to extend the usage of HA.Method:1.Test molecular weight of HA (Mr_ HA ) by viscosimetry;2.prepare cross-linked HA gels by DVS, GTA, DEC;3.discuss the cross-linking and degradation procedure;4.evaluate the biocompatibility of the best HA gels. Results:The mechanical stability and durability to degradation of HA-DVS gels are superior to those of other gels, and when HA:DVS = 40:1(g/g), at 35℃ and in 0.2 M NaOH solution, the HA-DVS gel shows the best mechanical stability, and its cytotoxicity reaches class I, hemolysis ratio is lower than 5%. Conclusion:Our HA-DVS gel can be used to prepare biologic scaffolds.