Although metal blocks have been widely used for reconstructing uncontained tibial bone defects, the influence of their elastic modulus on the stability of tibial prosthesis fixation remains unclear. Based on this, a finite element model incorporating constrained condylar knee (CCK) prosthesis, tibia, and metal block was established. Considering the influence of the post-restraint structure of the prosthesis, the effects of variations in the elastic modulus of the block on the von Mises stress distribution in the tibia and the block, as well as on the micromotion at the bone-prosthesis fixation interface, were investigated. Results demonstrated that collision between the insert post and femoral prosthesis during tibial internal rotation increased tibial von Mises stress, significantly influencing the prediction of block elastic modulus variation. A decrease in the elastic modulus of the metal block resulted in increased von Mises stress in the proximal tibia, significantly reduced von Mises stress in the distal tibia, decreased von Mises stress of the block, and increased micromotion at the bone-prosthesis fixation interface. When the elastic modulus of the metal block fell below that of bone cement, inadequate block support substantially increased the risk of stress shielding in the distal tibia and fixation interface loosening. Therefore, this study recommends that biomechanical investigations of CCK prostheses must consider the post-constraint effect, and the elastic modulus of metal blocks for bone reconstruction should not be lower than 3 600 MPa.
Knee Prosthesis ; Humans ; Finite Element Analysis ; Tibia/surgery* ; Elastic Modulus ; Arthroplasty, Replacement, Knee/methods* ; Stress, Mechanical ; Metals ; Prosthesis Design ; Knee Joint/surgery* ; Biomechanical Phenomena

Non-small cell lung cancer(NSCLC)is one of the malignant tumors with high morbidity and mortality worldwide.Ferroptosis is a new type of programmed cell death caused by abnormal accumulation of iron-dependent reactive oxygen species(ROS)leading to lipid peroxidation.It involves the balance between iron metabolism,lipid metabolism,oxy-gen free radical reaction and lipid peroxidation.Recent studies have found that ferroptosis is closely related to the occurrence and development of NSCLC.Due to the emergence of chemotherapy resistance and radiotherapy resistance in the treatment of NSCLC,there is an urgent need to develop new effective drugs and treatment strategies.Traditional Chinese medicine has unique advantages in the prevention and treatment of NSCLC due to its multi-targets and minimal side effects.In this review,we summarize the mechanism of ferroptosis in NSCLC,and discuss the research status of active ingredients of traditional Chinese medicine,single-herb traditional Chinese medicine and Chinese herbal compounds in the intervention of NSCLC through ferroptosis,in order to provide a new theoretical basis for the research of ferroptosis pathway and the prevention and treatment of NSCLC by targeted ferroptosis of traditional Chinese medicine.

Oral and maxillofacial space infection(OMSI)as a mostly mixed infection,often requires the combination of anti-aerobe and an-ti-anaerobe antibiotics.The use of third-generation quinolones,such as levofloxacin,is limited in OMSI due to the tendon rupture and other serious adverse drug reactions(ADR).In the treatment of a case with OMSI and anaphilactic shock induced by levofloxacin,the association evaluation method of ADR and literature review method participated by clinical pharmacists were used.Suggestions on rational drug use and ADR treatment were gained,the patient was timely rescued from anaphylactic and cured of OMSI.

Nano-engineering-based tissue regeneration and local therapeutic delivery strategies show significant potential to reduce the health and economic burden associated with craniofacial defects, including traumas and tumours. Critical to the success of such nano-engineered non-resorbable craniofacial implants include load-bearing functioning and survival in complex local trauma conditions. Further, race to invade between multiple cells and pathogens is an important criterion that dictates the fate of the implant. In this pioneering review, we compare the therapeutic efficacy of nano-engineered titanium-based craniofacial implants towards maximised local therapy addressing bone formation/resorption, soft-tissue integration, bacterial infection and cancers/tumours. We present the various strategies to engineer titanium-based craniofacial implants in the macro-, micro- and nano-scales, using topographical, chemical, electrochemical, biological and therapeutic modifications. A particular focus is electrochemically anodised titanium implants with controlled nanotopographies that enable tailored and enhanced bioactivity and local therapeutic release. Next, we review the clinical translation challenges associated with such implants. This review will inform the readers of the latest developments and challenges related to therapeutic nano-engineered craniofacial implants.
Humans ; Titanium ; Dental Implants ; Wound Healing ; Surface Properties

BACKGROUND: Standard two-dimensional (2D) culture has confirmed the mechanism of mast cells (MCs) in the pathogenesis of inflammatory bowel disease (IBD), but the regulation of signaling responses of MCs may well differ in three-dimensional (3D) microenvironments. The aim of the study was to develop a 3D culture model based on decellularized intestinal scaffolds (DIS) and verify how MCs influenced fibroblasts phenotype in the 3D model. METHODS: DIS were achieved using the detergent technique and extracellular matrix (ECM) components were verified by histologic analysis, quantification and scanning electron microscope. After human colon fibroblasts recellularized into the scaffolds and activated by MCs tryptase and TGFb1, the changes in genes and signaling pathways during fibroblasts activation in 3D were studied and compared with the changes in 2D cell culture on plastic plates. RESULTS: Decellularization process effectively removed native cell debris while retaining natural ECM components and structure. The engrafted fibroblasts could penetrate into the scaffolds and maintain its phenotype. No matter whether fibroblasts were cultured in 2D or 3D, MCs tryptase and transforming growth factor b1 (TGF-b1) could promote the differentiation of fibroblasts into fibrotic-phenotype myofibroblasts through Akt and Smad2/3 signaling pathways. Furthermore, the pro-collagen1a1 and fibronectin synthesis of myofibroblasts in 3D was higher than in 2D culture. CONCLUSION Our results demonstrated that the DIS can be used as a bioactive microenvironment for the study of intestinal fibrosis, providing an innovative platform for future intestinal disease modeling and screening of genes and signaling pathways.

Objective:To evaluate the effect of the comprehensive reforms of clinic-pharmacy separation and medical-consumables expenditure linkage in Beijing.Methods:Monitoring data of the comprehensive reforms were collected from 363 public medical institutions in Beijing between January 2016 and December 2019, while descriptive analysis and interrupted times series analysis using segmented regression models were adopted to analyze the influence of the two reforms on medical expense and its structure. We also studied the impact mechanism of service utilization and service price factors on medical expense control.Results:During the period from 2016 to 2019, the medical expenditure of public medical institutions in Beijing increased steadily at an annual growth rate of 4.4%-7.2%. The proportion of drug expense decreased from 44.6% in 2016 to 34.6% in 2019, while the proportion of medical service expense rose from 15.6% in 2016 to 24.3% in 2019, the proportion of examination and laboratory test expenses respectively showed a significant decline in April 2017 and June 2019. These two months witnessed respectively the launch of the two comprehensive reforms. Service utilization played an important role in controlling outpatient and emergency expenses, and service price was the key factor for controlling inpatient expenditure.Conclusions:The implementation of the two reforms in Beijing has effectively curbed the unreasonable growth of medical expenditure, and the expense structure has been constantly optimized and labor value of medical staff gradually improved.

Objective: To identify the characteristics of social network and the association between ego-centric network and HIV status among young MSM Chinese students. Methods: The cross-sectional study was conducted in Chongqing, Tianjin, Harbin and Xi an city from April to December 2017 and from March to May 2018. A mixed recruitment method of snowball sampling and RDS approach was used to recruit participants who reported information on social network and received HIV test. The Multiple Regression Analysis method was used to for the analysis of association between ego-centric social network and HIV status of men who have sex with men (MSM) among young students. Results: The sample included 547 participants who nominated 1 088 social partners in total with average age of 13 to 60 years old. The MSM with different sexual orientation from their social members (aOR=0.38), embedded in a large network (aOR=0.63), with a high individual betweenness centrality (aOR=0.27) were at lower risk of HIV-positive status; while MSM who differed greatly in education level with their social members(aOR=1.60), existed in sexual networks(aOR=1.41), existed in the “risky networks” (aOR=1.88) , with high network density (aOR=1.91) and a high individual degree (aOR=4.10) had higher risk of HIV-positive status(P<0.05). Conclusion MSM with great difference in education level from social members, existed in sexual networks, with a large network density and a high degree were exposed to higher risk of HIV-positive status.

Objective: To understand the characteristics of sexual partners and the influence of having multiple sexual partners on substance use among young male students man who have sex with men (MSM) in China, and to provide scientific basis for the prevention and control of HIV/AIDS among young MSM students. Methods: A mixed recruitment method of snowball sampling and respondent driven sampling was used to recruit young MSM students in Beijing and Tianjin, and a questionnaire survey was conducted among 220 participants from November to December 2019. Chi-square test and generalized linear model multi-factor Logistic regression were used to analyze the influencing factors of substance use before sexual behavior. Results: The average age of them was (22.39±2.57) years old, 84.5% of them were students, the average age of first sexual behavior was (18.83±2.45) years old, 44.1% of them had two or more sexual partners (including fixed sexual partners, temporary sexual partners and commercial sexual partners), 22.7% had more than one male fixed partner. After adjusting for age and education, having multiple sexual partners was risk factor for drinking alcohol before sex (aOR=2.97) or substance abuse (aOR=2.39). Having male temporary sexual partner was an risk factor in substance use before sexual behavior(OR=4.10). Conclusion The characteristics of sexual partners among young MSM students are complex, and the proportion of multiple sexual partners is high. Having fixed single sexual partner can reduce the risk of substance use before sexual behavior. AIDS prevention education for young MSM students should be further strengthened.

Objective:To observe the clinical effect of hormone replacement therapy(HRT) on patients with cervical squamous cell carcinoma after operation and its effect on sex hormone, blood fat, bone content and tumor markers, and to evaluate the clinical significance of HRT therapy.Methods:From January 2016 to January 2019, a total of 100 patients with cervical squamous cell carcinoma admitted to Zhuhai Maternal and Child Health Hospital were analyzed retrospectively.After surgical treatment, 50 patients were willing to receive hormone replacement therapy as the experimental group and 50 patients received routine treatment as the control group, Kupperma score was used to evaluate the severity of perimenopausal symptoms, and the serum levels of sex hormones, blood fat, bone content and tumor markers in the two groups before and after treatment were detected and the occurrence of adverse reactions were evaluated.Results:Before treatment, there was no significant difference in kupperma score, estradiol, follicle-stimulating hormone, luteinizing hormone level, lipid level, bone content and tumor marker level between the two groups(all P>0.05). After HRT treatment, kupperma score in the experimental group was significantly lower than that before treatment((11.47±5.12) vs.(20.46±7.52), t=7.262). In the detection of sex hormones, the levels of estradiol in the experimental group was significantly increased((39.26±7.43) ng/L vs.(13.78±7.52) ng/L, t=12.345), and the levels of follicle stimulating hormone((34.25±7.61) U/L vs.(62.18±19.12) U/L, t=8.245)and luteinizing hormone((20.31±6.25) U/L vs.(35.08±6.27) U/L, t=5.452, P=0.004) in the experimental group were significantly decreased.In the detection of blood lipid level, bone content and tumor markers, high-density lipoprotein((1.62±0.33) mmol/L vs(1.34±0.26) mmol/L, t=4.592, P=0.008) and alkaline phosphatase levels((66.21±25.75) U/L vs.(46.88±9.06) U/L, t=5.912, P=0.001)was significantly increased, the low density lipoprotein((2.78±0.43) mmol/L vs.(2.87±0.78) mmol/L, t=4.265, P=0.012)and total cholestenone((4.02±0.45) mmol/L vs.(4.23±0.91) mmol/L, t=5.761, P=0.002) levels were significantly decreased in the experimental group, with statistically significant differences(all P<0.05). There was no significant difference in the level of serum SCC antigen between the experimental group and the control group before and after treatment ( P> 0.05); there was no significant difference in the above indicators between the experimental group and the control group before and after treatment ( P> 0.05); there was no significant increase in adverse reactions such as breast swelling and pain (3 cases), body mass increase (2 cases), bleeding (1 case), body pain (4 cases), vomiting (4 cases), etc. between the experimental group and the control group (2, 1, 2, 3, 1 case) There was no statistical significance ( P> 0.05). Conclusion:HRT treatment of cervical squamous cell carcinoma patients after surgery can significantly improve the peri menstrual syndrome caused by low estrogen level, and did not significantly increase the risk of recurrence of cervical cancer patients and adverse reactions.