BACKGROUND:The anterior cruciate ligament has unique nonlinear mechanical properties under a complex physiological loading environment.Elastin is an important contributor to the mechanical properties of the anterior cruciate ligament,but its mechanical response to the anterior cruciate ligament under axial tension is not clear. OBJECTIVE:To quantitatively analyze the effect of elastin on the tensile mechanical response of the anterior cruciate ligament. METHODS:Elastase solution and control buffer were prepared.The porcine anterior cruciate ligament samples were prepared into small-size samples and randomly soaked in 0,0.1,1.0,2.0,5.0,and 10.0 U/mL elastase solution for 6 hours,and other small samples of the same size were soaked in 2 U/mL elastase solution for 0,1,3,6,9,and 12 hours.To determine suitable soaking conditions for elastin-targeted enzymes and verify the digestive effect,histological staining was used to compare the effects of enzyme treatment on tissue structure and composition.The ligament samples were randomly divided into elastase-treated group and PBS group,and immersed in 2 U/mL elastase solution and PBS buffer for 6 hours,respectively.A mechanical tensile test was performed before and after immersion. RESULTS AND CONCLUSION:(1)The biochemical results showed that being treated in 2 U/mL elastase solution for 6 hours could reduce the elastin content by 31.1%,and had no significant effect on other mechanical-related components in the tissue.(2)The histological results showed that elastase was able to penetrate the tissue,and the loose degree of tissue increased after treatment.(3)In the mechanical results before and after treatment,the mechanical properties of the PBS group decreased significantly,only the low-tension elastic modulus increased significantly and the initial length increased significantly in the elastase-treated group.(4)The intergroup comparison results showed that there was no significant difference between the two groups in pre-treatment,but the low-tension elastic modulus,initial slopes,saturated slopes,and initial length of the elastase-treated group after treatment were significantly higher than those in the PBS group.(5)These results suggest that elastin degradation significantly affects the biomechanical properties of the anterior cruciate ligament and further complements our understanding of the structure-function relationship of the anterior cruciate ligament.

Background and purpose:Long noncoding RNA(lncRNA)can regulate gene transcription,mRNA shear,stabilization and translation,and it is an important regulatory factor in a variety of biological processes.This study aimed to investigate the expression and clinical features of lncRNA FLJ30679 in oral squamous cell carcinoma(OSCC)and its effect on the malignant biological behavior of OSCC.Methods:The expression of FLJ30679 in head and neck squamous cell carcinoma(HNSCC)tissues and normal tissues was analyzed by the UCSC Xena database for expression and prognosis.The expression of FLJ30679 in OSCC cell lines was detected by real-time fluorescence quantitative polymerase chain reaction(RTFQ-PCR).The subcellular localization of FLJ30679 in OSCC cells was detected by RNA nuclear-cytoplasmic fractionation assays.FLJ30679 Smart Silencer was used to establish the FLJ30679 knockdown group(SS-FLJ30679),and overexpression plasmid of FLJ30679 was used to establish FLJ30679 overexpression group(FLJ30679).The effects of altered FLJ30679 expression on the proliferative and migration capacity of OSCC cells were examined by cell counting kit-8(CCK-8)and transwell migration assays.RTFQ-PCR and Western blot were used to determine the effect of altered FLJ30679 expression on the expression of epithelial-mesenchymal transition(EMT)-related genes in OSCC cells.The effects of altered FLJ30679 expression on the phosphoinositide 3-kinase(PI3K)/protein kinase(AKT)pathway were detected by Western blot.Results:Online query of database showed that FLJ30679 expression was higher in HNSCC tissues compared to normal tissues(P＜0.01).HNSCC patients with higher FLJ30679 expression had lower overall survival(P＜0.01).The RTFQ-PCR results showed that FLJ30679 was expressed at a higher level in six OSCC cell lines compared with normal cells,and was predominantly localized in the nucleus.The ability of OSCC cells in the SS-FLJ30679 group to proliferate and migrate was significantly lower compared with the SS-NC group(P＜0.01).OSCC cells in the FLJ30679 overexpression group had significantly higher proliferative and migratory capacities than those in the vector group(P＜0.001).RTFQ-PCR and Western blot results showed that FLJ30679 knockdown resulted in upregulation of mRNA and protein expression levels of E-cadherin(P＜0.01)and downregulation of mRNA and protein expression levels of N-cadherin and vimentin(P＜0.01).FLJ30679 overexpression resulted in downregulation of protein expression levels of E-cadherin(P＜0.01)and upregulation of mRNA and protein expression levels of N-cadherin and vimentin(P＜0.05).Western blot results showed that knockdown of FLJ30679 resulted in decreased protein expression levels of phosphorylated-PI3K(p-PI3K)and phosphorylated-AKT(p-AKT)(P＜0.001),and overexpression of FLJ30679 resulted in increased protein expression levels of p-PI3K and p-AKT(P＜0.01).Conclusion:The expression of FLJ30679 was increased in OSCC tissues and cells.It promoted the proliferation and migration ability of OSCC cells,which may be caused by FLJ30679 promoting EMT via PI3K/AKT pathway.

Escherichia coli is a highly adaptable opportunistic pathogen bacterium that can form biofilms on the surface of implants and generates persistent cells,leading to life-threatening infections that are difficult to treat with antibiotics alone.Therefore,there is a need for an effective E.coli biofilm inhibitor to combat this public health threat.Indole is a novel quorum-sensing signaling molecule of E.coli discovered in recent years,which is of great significance in regulating bacterial growth and biofilm formation,and is a potential target for future research on new anti-biofilm preparations.This article reviews the research progress on the formation of Escherichia coli biofilms,the microbial metabolism of indole and its regulation of Escherichia coli biofilm formation,in order to provide information for clinical treatment and drug development.

With the development of corneal refractive surgery, especially the application of femtosecond laser, and the lack of corneal donor, corneal stromal lenticules produced in refractive surgery have gradually attracted the attention of ophthalmologists.Most fresh corneal stromal lenticules are difficult to put into use immediately, so how to better preserve and treat the lenticules is a problem that ophthalmologists need to solve.Corneal stromal lenticules can be used in the treatment of many kinds of ophthalmic diseases.In this article, the preservation and treatment of corneal stromal lenticules, as well as its application and prospects in treating hyperopia and presbyopia, keratoconus, corneal ulcer, corneal dystrophy, dermoid tumors and recurrent pterygium, corneal thinning after laser in situ keratomileusis, and covering glaucoma drainage valve to prevent exposure were reviewed to provide reference for further clinical research and application.

Objective:To explore ways and methods for public mental health intervention during the COVID-19 epidemic.Methods:A comprehensive literature review was conducted. Mental healthcare publicity materials posted by over 100 Chinese hospitals in multiple media (till February 24, 2020) were also systematically collected and analyzed.Results:Firstly, anxiety and fear were the most common mental health problems among people during the epidemic. Secondly, to achieve better outcomes, mental health intervention should be provided according to the type of service clients. Thirdly, new media can facilitate the transmission of mental healthcare knowledge, but the limitation is that it can not approach older adults who have limited access to new media. It is therefore essential to strengthen the mental health knowledge transmission to older adults.Conclusions:Mental health intervention is effective when it is provided according to the type of service clients during the COVID-19 epidemic.

Objective To investigate the relationship between aberrant expression of interleukin 6 (IL-6) and gene methylation in patients with ulcerative colitis (UC),and to clarify the mechanism of epigenetics in UC.Methods From March 2017 to March 2018,a total of 59 UC patients admitted to the Department of Gastroenterology,General Hospital Affiliated to Tianjin Medical University were enrolled,and at the same time 58 normal individuals who received health checkups were selected as healthy controls.Blood samples and colonic mucosa specimens of UC group and healthy control group were collected.DNA methyltransferase (DNMT) activity,methylation level of CpG locus in IL-6 promoter region and expression level of IL-6 were detected.Chi-square test and student's t test were performed for statistical analysis.Results The methylation level and IL-6 expression level examination were completed in 24 and 30 cases of UC group,respectively;which were detected in 21 and 20 cases of healthy control group,respectively.The activity of DNMT of UC group was significantly lower than that of healthy control group ((16.48 ± 6.17) OD · h-1 · mg-1 vs.(62.48 ± 33.88) OD · h-1 ·mg-1),and the difference was statistically significant (t =3.707,P ＜ 0.05).The ratios of methylation,partial methylation and non-methylation of UC group were 31.2％ (15/48),50.0％ (24/48) and 18.8％ (9/48),respectively,and those of healthy control group were 58.3％ (35/60),21.7％ (13/60) and 20.0％ (12/60),and the difference between the two groups was statistically significant (x2 =10.495,P ＜ 0.05).The positive expression rate of IL-6 in intestinal mucosa of UC group was higher than that of healthy control group (100.0％,21/21 vs.25.0％,5/20),and the difference was statistically significant (x2 =24.837,P ＜0.05).The serum IL-6 level of UC group was higher than that of healthy control group ((1 075.02 ±661.95) ng/L vs.(583.43 ± 425.10) ng/L),and the difference was statistically significant (t =3.245,P ＜ 0.05).Conclusion The decrease of DNMT activity in the intestinal mucosa of UC patients may reduce the methylation level of IL-6 gene promoter region,which is correlated with the increased level of IL-6 expression in the intestinal mucosa and serum,and involve in the inflammatory process of UC.

Objective To introduce the classification of the perforators of the superficial circumflex iliac artery(SCIA),and the superficial circumflex iliac artery perforator (SCIP) flaps based on different perforators have different characters and harvesting methods.To explore a set of coping strategy for the drawbacks of the SCIP flap.Methods Review 90 cases of SCIP flaps in August,2011 to June,2017.The pre-operative radiology navigation was conducted in all cases.Different surgical approaches were applied in flaps based on different perforators.The pedicle elongation method was adopted when necessary.The thickness of the flap,the length of the pedicle,the survival rate of the flap and the closure of the donor site were analyzed.Regular follow-up was performed after the operation.Results All flaps were followed-up for 6-15 months (average 8 months).Fifty-seven flaps were raised on the basis of the proximal perforators of the superficial branch of the SCIA,whereas 29 cases were based on the distal perforators from the deep branch,and in 4 cases,the pedicle was switched to the superficial inferior epigastric artery.In 8 cases,the arterial pedicle lengthen technique was applied with a maximum length of 10 cm.All donor sites were closed directly.Conclusion These surgical strategies simplified the intraoperative decision-making and conquered the shortcomings of the SCIP flap.It is believed that the SCIP flap can possibly become the new workhorse flap in the field of reconstructive surgery.

Objective To study the clinical value of double balloon endoscopy (DBE) in diagnosis and treatment of intestinal diseases. Methods Clinical data of 344 patients suspected of small bowel lesions from March 2006 to April 2014 was retrospectively analyzed. All the patients clinical manifestations including varying degrees of abdominal pain, bloating, nause and vomiting, diarrhea. The 344 patients underwent DBE for 397 times. Results The incidence of adverse reactions in checking was only 4.53%, and there was no complications occurred after checking. Positive results shown in 214 cases by DBE, the other 130 patients shown negative results. While 28 of the other 130 patients were found small bowel lesions by capsule endoscopy and CT scans, the remaining 102 cases had no obvious abnormalities. The misdiagnosis rate of DBE was 8.13%, and mainly focuses on polyps and vascular malformation. 242 of the 344 patients were diagnosed with intestinal diseases, and mostly of them were tumor, ulcers and polyps. The detect rate of DBE examination for tumor and ulcer diseases was greater than that of small intestinal polyposis, the difference was statistically significant (P < 0.05). Conclusion DBE in diagnosis and treatment of intestinal diseases is a relatively safe and effective way. It is worthy being popularized and applied.

BACKGROUND: Bone exposed wounds are frequently required to deal with in orthopaedic surgeries, involving the treatment of open fractures, bone tumors, osteomyelitis, and many other diseases, in which the defect of soft tissue caused by open fractures is the most difficult to deal with. Conventional debridement or negative pressure closed drainage technology is difficult to make bone exposed wounds heal, and the process is extremely cumbersome, during which,patients suffer a lot of pain.OBJECTIVE: To evaluate the advantages and disadvantages of the various types of dressings, and review the application of new hydrogel dressing in bone exposed wounds based on its advantages, such as keeping wound environment moisture, restoring skin physical barrier, contributing to routine dressing change.METHODS: A computer-based online retrieval of PubMed and CNKI databases was performed to search papers published between 2000 and 2016 using the key words hydrogel dressing, bone exposed wound, traditional wound dressing, antibiotic in English and Chinese, respectively. A total of 55 papers suitable for final analysis from the application of traditional and new dressings in bone tissue engineering were reviewed.RESULTS AND CONCLUSION: The treatment of bone exposed wounds involves the treatment of many diseases, such as open fractures, bone tumors, osteomyelitis, which is still an orthopedic problem to solve. The novel hydrogel dressings with unique advantages are able to provide better plans for bone exposed wounds, and the use of these dressings solves the regeneration and repair of exposed bone, and improves the infection of antibiosis. In addition, the gel dressings currently have become a hot spot of research because of the characteristics of sustained-release.

Objective To evaluate the valuse of endoscopic ultrasonography ( EUS ) for upper gastrointestinal submucosal lesions and the role of Photoshop in differentiating leiomyoma and stromal tumors. Methods Data of 656 patients with upper gastrointestinal submucosal lesions evaluated by EUS and receiving endoscopic submucosal dissection ( ESD ) from April 2010 to March 2015 were collected and retrospectively analyzed. The goldern standard for lesions size and origin was the intraoperative diagnosis of ESD, and that of the type of lesions ( leiomyoma, stromal tumor, ectopic pancreas, lipoma, etc.) was pathological and immunohistochemical finding. The consistency of diagnosis of the EUS was evaluated. In addition, Photoshop was used to differentiate diagnosis of leiomyoma and stromal tumors which were confirmed by pathology and immunohistochemistry. Results The consistency in diagnosing the size and lesion origins was 92?56%(560/605) and 88?43%(535/605)between EUS and ESD intraoperative result. The consistency in pathological types of EUS was 79?34%(480/605). Photoshop was used to analyze the EUS images of 177 stromal tumor and 241 leiomyoma. The gray value of stromal tumor was significantly higher than that of leiomyoma(59?97 VS 39?39, t=43?27, P<0?05).The echo of stromal tumor was higher. The standard deviation of gray value of leiomyoma were significantly lower than that of the stromal tumor ( 4?81 VS 5?42, t = 2?83, P < 0?05 ) , indicating the echo uniformity of leiomyoma was better. Conclusion EUS shows high accuracy rate for upper gastrointestinal submucosal lesions, providing more accurate basis for endoscopic therapy. EUS combined with Photoshop is helpful for differentiating stromal tumor from leiomyoma.