Objective:To construct a microfluidic organ-on-a-chip and evaluate its capability in simulating subchondral bone remodeling during the progression of osteoarthritis.Methods:The chip′s main body was designed based on the microfluidic technology and cell co-culture technique. MC3T3-E1 cells were cultured adherently within the cell seeding micro-chamber, with the culture medium perfused at a flow rate of 0.5 ml/min at the bottom of the micro-chamber. Evaluation metrics were as follows: (1) Assessment of the microfluidic organ-on-a-chip: The growth culture medium was perfused and simulation experiments were conducted to test the concentration differences and equilibrium times of the fluid inside and at the bottom of the cell seeding micro-chamber at various time points; live-dead staining was performed to observe the biocompatibility of cells cultured continuously for 3 days and 7 days at a set flow rate, which was divided into 3-day and 7-day groups. (2) Osteogenic potential of the microfluidic organ-on-a-chip: The osteogenic induction medium was perfused, and ALP staining and PCR were performed to compare the number of the black alkaline phosphatase (ALP)-positive cells and the expression levels of osteogenesis-related marker genes including osteoblast-specific transcription factor 2 (RUNX2), type I collagen (COL1A1), bone morphogenetic protein-2 (BMP-2), and osteocalcin (OCN) under static, 3-day and 7-day perfusion conditions, which was divided into static non-induced, static-induced and perfusion-induced groups. (3) Characterization of morphology and size, and biocompatibility of extracellular vesicles (EVs) of three osteoblast subtypes: Three different subtypes of osteoblasts were obtained [endothelial-type osteoblasts (EnOB)-EVs, stromal-type osteoblasts (StOB)-EVs and mineralizing-type osteoblasts (MinOB)-EVs]. Their morphology and size were obtained through transmission electron microscopy and particle size analysis. Growth medium containing EVs of three different cell subtypes was perfused, and cell proliferation/apoptosis assay was performed to compare the biocompatibility of the addition of different EVs concentrations (1, 1.25, 2.5, and 5 μg/ml) for 24 hours, which was categorized into the EnOB-EVs group, StOB-EVs group and MinOB-EVs group. (4) Osteogenic effect of EVs from three subtypes of osteoblasts: Osteogenic induction media containing EVs from three different osteoblast subtypes were perfused for 3 days, and ALP staining and PCR were performed to compare the number of black ALP-positive cells and the expression levels of osteogenesis-related marker genes including RUNX2, COL1A1, BMP-2, and OCN, which was divided into non-EVs group, EnOB-EVs group, StOB-EVs group and MinOB-EVs group.Results:(1) Evaluation of the microfluidic organ-on-a-chip: Simulation results showed that the concentration in the top layer of the upper chamber reached more than 95% of that in the lower chamber and that the concentration in the bottom layer was about 96.5% of that in the lower chamber after 12 hours of continuous perfusion, reaching an equilibrium state of the concentration difference between the upper and lower chambers. The results of live-dead staining showed that the chip was biocompatible at a flow rate of 0.5 ml/min, and the cell survival rate at 3 and 7 days of perfusion was (99.48±0.12)% and (97.07±1.05)% ( P<0.01). (2) ALP staining results showed that at 3 days, the perfusion-induced group showed the highest number of black ALP-positive cells, followed by the static-induced group, and the least in the static non-induced group. At 7 days, the static-induced group had the highest number of black ALP-positive cells, followed by the perfusion-induced group, and the least in the static non-induced group. PCR results indicated that at 3 days, the expression levels of RUNX2, COL1A1, BMP-2, and OCN were 1.00±0.03, 1.00±0.12, 1.00±0.01, and 1.00±0.02 respectively in the static non-induced group; 1.80±0.04, 4.05±0.37, 9.80±1.94, and 4.38±0.89 respectively in the static-induced group, and 2.45±0.23, 5.48±0.42, 91.50±4.56, and 10.82±4.96 respectively in the perfusion-induced group ( P<0.01). At 7 days, the expression levels of RUNX2 was 1.00±0.01 in the static non-induced group, 1.46±0.46 in the static-induced group, and 1.11±0.08 in the perfusion-induced group ( P>0.05); the expression levels of COL1A1, BMP-2, and OCN were 1.00±0.03, 1.00±0.13, and 1.00±0.09 respectively in the static non-induced group, 9.38±0.25, 14.27±4.35, and 84.01±4.02 respectviely in the static-induced group, and 2.39±0.08, 133.64±8.87, and 86.64±8.36 respectively in the perfusion-induced group ( P<0.01). When comparing the static non-induced, static-induced, and perfusion-induced groups at both 3 and 7 days, the perfusion-induced group demonstrated the strongest osteogenic capability. (3) Characterization of morphology and size and biocompatibility of EVs from three osteoblast subtypes: Under the transmission electron microscope, EVs from EnOB-EVs, StOB-EVs, and MinOB-EVs all exhibited a typical saucer-shaped morphology. The particle sizes of EnOB-EVs, StOB-EVs, and MinOB-EVs were (91.3±14.7)nm, (106.0±16.0)nm, and (68.1±10.7)nm, respectively. Cell proliferation/apoptosis assay results indicated that the optimal administration concentration of EnOB-EVs, StOB-EVs, and MinOB-EVs was all 1.25 μg/mL. (4) Validation of osteogenic effect of the microfluidic organ-on-a-chip on three types of EVs: ALP staining results showed that the non-EVs group had the fewest black ALP-positive cells, followed by the EnOB-EVs group, then the StOB-EVs group, and the MinOB-EVs group had the most. PCR results showed that the expression levels of RUNX2, COL1A1, BMP-2, and OCN were 1.00±0.01, 1.00±0.03, 1.00±0.02, and 1.00±0.02 respectively in the non-EVs group, 1.95±0.11, 6.78±2.04, 7.99±0.57, and 6.93±3.83 repectively in the EnOB-EVs group, 0.79±0.12, 5.68±1.53, 12.59±3.15, and 25.59±0.95 respectively in the StOB-EVs group, and 0.68±0.10, 4.36±0.69, 18.75±3.21, and 34.74±3.98 repectively in the MinOB-EVs group ( P<0.01). Compared with the non-EVs group, EnOB-EVs group, StOB-EVs group, and MinOB-EVs group, the MinOB-EVs group showed the most significant osteogenic effect. Conclusions:The microfluidic organ-on-a-chip constructed using microfluidic technology and cell co-culture techniques is capable of maintaining the normal growth of MC3T3-E1 cells, enhancing their proliferation and osteogenic induction differentiation. EVs released by osteoblasts at different stages possess osteogenic effects and can accelerate the bone sclerosis in the remodeling of subchondral bone during the progression of osteoarthritis.

In recent years, clinicians have paid more attention to the biological and esthetic effects of the 2 mm keratinized mucosa width (KMW) around dental implant. How to increase the keratinized mucosa is the focus of clinicians. While the free gingival graft (FGG) is still the gold standard of keratinized mucosa augmentation, alveolar ridge preservation (ARP), connective tissue graft (CTG) and apically positioned flap (APF) can also be used to obtain more than 2 mm keratinized mucosa width when they are used before implantation, with implantation, within the implant-healing phase, with second stage of implantation or after rehabilitation according to different indications. This article comprehensively summarizes the influencing factors of timing and surgical procedures for keratinized mucosa augmentation, providing guidance for clinicians to treat peri-implant keratinized mucosa deficiencies.

Objective To investigate the effect of tigecycline on coagulation function and to provide a reference for the clinical rational use of tigecycline.Methods The data of patients treated with tigecycline in Shanghai Tenth People's Hospital between June 2019 and December 2023 by retrospective analysis.Statistical analysis was performed by collecting data on patients'basic information,routine coagulation parameters and thromboelastogram(TEG)parameters before and after the use of tigecycline.Results Activated partial thromboplastin time,prothrombin time and thrombin time were prolonged and fibrinogen levels were decreased with the use of tigecycline in 41 patients,the differences were statistically significant(P＜0.05).There was no significant difference in levels of coagulation factor activation time,clot formation rate parameter,maximum angle of tangency,maximum amplitude of elastography and coagulation index after treatment with tigecycline(P＞0.05).Conclusion For patients with suspected coagulation abnormalities after tigecycline administration,a comprehensive assessment of coagulation should be made by combining routine coagulation indexes with TEG.

Objective:To compare the clinical efficacy between robot-assisted and free-hand percutaneous cannulated screwing (PCS) in the treatment of femoral neck fractures in the middle-aged and young patients.Methods:A retrospective study was conducted to analyze the clinical data of 53 patients with femoral neck fracture who had been treated with PCS from May 2020 to May 2022 at Department of Traumatic Surgery, Maoming Hospital Affiliated to Southern Medical University. In the robot group of 25 patients subjected to robot-assisted PCS, there were 11 males and 14 females with an age of (48.2 ± 11.9) years; in the free-hand group of 28 patients subjected to free-hand PCS, there were 13 males and 15 females with an age of (48.5 ± 9.8) years. The 2 groups were compared in terms of operation time, intraoperative bleeding, intraoperative guide drills, intraoperative fluoroscopy frequency, fracture union time, Harris hip score at the last follow-up and postoperative complications. Postoperative imaging examination was performed to evaluate distribution accuracy of the cannulated screws in the femoral neck (deviation between the screws and the femoral neck axis, parallelism between the screws and distance between the screws and the neck cortex).Results:There was no statistically significant difference between the robot and free-hand groups in the general clinical data before operation, showing comparability ( P>0.05). The robot group showed significantly shorter operation time [(32.7 ± 4.8) min], significantly less intraoperative bleeding [(14.6 ± 4.8) mL], significantly less intraoperative guide drillings [(3.5 ± 0.7) times] and significantly less intraoperative fluoroscopy frequency [(7.9 ± 1.4) times] than the free-hand group [(56.9 ± 11.3) min, (27.0 ± 7.3) mL, (9.1 ± 1.8) times and (16.3 ± 6.0) times)] (all P<0.05). Postoperative imaging showed that the deviation between the screws and the femoral neck axis was 4.4° ± 1.1° on the anteroposterior X-ray film and 3.2° ± 0.8° on the lateral X-ray film, the parallelism between the screws 4.9° ± 0.8° on the anteroposterior X-ray film and 3.0° ± 0.7° on the lateral X-ray film, and the distance between the screws and the femoral neck cortex (10.4 ± 2.7) mm in the robot group, all significantly smaller than those in the free-hand group [10.5° ± 2.8°, 4.9° ± 1.1°, 12.1° ± 4.0°, 5.1° ± 1.3°, and (15.4 ± 3.2) mm] (all P<0.05). All the 53 patients were followed up for (22.2 ± 8.5) months. All fractures got united. The fracture union time in the robot group [(20.6 ± 4.6) weeks] was insignificantly shorter than that in the free-hand group [(23.7 ± 7.7) weeks] ( P>0.05). At the last follow-up, the Harris hip score in the robot group [(88.6 ± 5.6) points] was significantly higher than that in the free-hand group [(84.8 ± 6.3) points] ( P<0.05). Follow-ups revealed 2 cases of internal fixation loosening, 1 case of screw head cutting and 1 case of femoral head necrosis in the free-hand group but none of such complications in the robot group. Conclusion:In the treatment of femoral neck fractures in the middle-aged and young patients, compared with free-hand PCS, robot-assisted PCS shows advantages of shorter intraoperative time, less bleeding, less fluoroscopic radiation, higher accuracy of screw placement, a lower incidence of postoperative complications and better functional recovery of the hip joint.

Objective:To evaluate the efficacy and safety of sodium hyaluronate gel in preventing adhesion after prophylactic enterostomy.Methods:One hundred and twenty four patients from 6 hospitals were enrolled in this prospective multi-center randomized controlled trial. Patients were randomized into the study group ( n=59) or the control group ( n=65).All patients underwent prophylactic enterostomy. Patients of study group received odium hyaluronate gel for adhesion-prevention,while those in control group did not receive any adhesion-prevention treatment. The incidence of moderate to severe adhesion around the incision in the stoma area were evalutated during stoma reduction surgery. Results:The incidence of moderate to severe adhesion around the incision in the stoma area was 6.3% in the study group, the difference was statistically significant ( P<0.05) compared to that of the control group (32.6%). Conclusion:Sodium hyaluronate gel can safely and effectively reduce the incidence of moderate and severe adhesions after abdominal surgery.

Objective To explore the effective management of post-operation infections through clinical pharmacists participating in the treatment of a gastric cancer patient with post operation abdominal infection and cellulitis. Methods Clinical pharmacists provided an rational anti-infective treatment plan with the combination of pharmacy and clinical practice, conducted medication education for the patient, and participated in the process of pharmacy care for the patient. Results Physicians modified the medication plan according to the recommendations from the clinical pharmacists. The patient’s infection was effectively controlled and the symptoms were alleviated. Conclusion With their professional knowledge, clinical pharmacists can select the best antibacterial drug regimen for the treatment of post-operation infections and provide patients with optimal pharmaceutical care.

Considering the substantial role played by dendritic cells (DCs) in the immune system to bridge innate and adaptive immunity, studies on DC-mediated immunity toward biomaterials principally center on their adjuvant effects in facilitating the adaptive immunity of codelivered antigens. However, the effect of the intrinsic properties of biomaterials on dendritic cells has not been clarified. Recently, researchers have begun to investigate and found that biomaterials that are nonadjuvant could also regulate the immune function of DCs and thus affect subsequent tissue regeneration. In the case of proteins adsorbed onto biomaterial surfaces, their intrinsic properties can direct their orientation and conformation, forming "biomaterial-associated molecular patterns (BAMPs)". Thus, in this review, we focused on the intrinsic physiochemical properties of biomaterials in the absence of antigens that affect DC immune function and summarized the underlying signaling pathways. Moreover, we preliminarily clarified the specific composition of BAMPs and the interplay between some key molecules and DCs, such as heat shock proteins (HSPs) and high mobility group box 1 (HMGB1). This review provides a new direction for future biomaterial design, through which modulation of host immune responses is applicable to tissue engineering and immunotherapy.
Biocompatible Materials/metabolism* ; Dendritic Cells/metabolism* ; Tissue Engineering ; Immunomodulation ; Adaptive Immunity

Metabolic-associated fatty liver disease (MAFLD), which is previously known as non-alcoholic fatty liver disease (NAFLD), represents a major health concern worldwide with limited therapy. Here, we provide evidence that ferroptosis, a novel form of regulated cell death characterized by iron-driven lipid peroxidation, was comprehensively activated in liver tissues from MAFLD patients. The canonical-GPX4 (cGPX4), which is the most important negative controller of ferroptosis, is downregulated at protein but not mRNA level. Interestingly, a non-canonical GPX4 transcript-variant is induced (inducible-GPX4, iGPX4) in MAFLD condition. The high fat-fructose/sucrose diet (HFFD) and methionine/choline-deficient diet (MCD)-induced MAFLD pathologies, including hepatocellular ballooning, steatohepatitis and fibrosis, were attenuated and aggravated, respectively, in cGPX4-and iGPX4-knockin mice. cGPX4 and iGPX4 isoforms also displayed opposing effects on oxidative stress and ferroptosis in hepatocytes. Knockdown of iGPX4 by siRNA alleviated lipid stress, ferroptosis and cell injury. Mechanistically, the triggered iGPX4 interacts with cGPX4 to facilitate the transformation of cGPX4 from enzymatic-active monomer to enzymatic-inactive oligomers upon lipid stress, and thus promotes ferroptosis. Co-immunoprecipitation and nano LC-MS/MS analyses confirmed the interaction between iGPX4 and cGPX4. Our results reveal a detrimental role of non-canonical GPX4 isoform in ferroptosis, and indicate selectively targeting iGPX4 may be a promising therapeutic strategy for MAFLD.

Objective:To evaluate the anterior expansion of sacral foramen and decompression of sacral plexus via the lateral-rectus approach (LRA) in the surgical treatment of sacral fractures complicated with sacral plexus injury.Methods:From January 2013 to June 2018, 11 patients were treated at Department of Orthopaedics, The Third Hospital Affiliated to Southern Medical University for obsolete sacral fractures complicated with sacral plexus injury. They were 8 males and 3 females, aged from 17 to 54 years (average, 38 years). According to the Denis classification, all the sacral fractures belonged to Denis Zone Ⅱ. According to British Medical Research Council (BMRC) grading system, the nerve injury was complete damage in 2 cases and partial damage in 9. The mean time from injury to surgery was 6 months (range, from 0.7 to 12.0 months). After the sacroiliac joint was exposed via the LRA, the lumbosacral trunk was exposed and released between iliac vessels and the iliopsoas. Next, the S1 foramen was expanded and the S1 nerve root was released after separation of the median sacral artery and the internal iliac artery. Reduction and fixation of the sacroiliac joint was carried out for patients with unstable sacral fracture. X-ray and CT examinations of the pelvis were performed to evaluate fracture healing and neurological function recovery postoperatively.Results:Of this cohort of 11 cases, operation succeeded in 10 but failed in one whose sacral fracture was found to have completely healed with the S1 foramina totally occluded. The surgical time averaged 110 min (range, from 70 to 220 min) and the blood loss 1, 100 mL (range, from 450 to 2, 800 mL). Postoperative X-ray and CT examinations showed that the sacral foramens were expanded significantly without any complications. The follow-up time averaged 18 months (range, from 12 months to 4 years). By the BMRC grading system at the last follow-up, the neural function was completely recovered in 5 cases, partially recovered in 4 cases and not recovered in one.Conclusion:Significant anterior expansion of sacral foramen and decompression of sacral plexus via the LRA is a viable and effective alternative for treatment of sacral fractures complicated with sacral plexus injury.

Objective:To explore the efficacyof direct anterior approach (DAA) combined with direct posterior approach (DPA) for the treatment of Pipkin IV fracture.Methods:Data of 18 patients with Pipkin IV fracture treated through DAA combined with DPA from January 2016 to April 2019 was retrospectively analyzed. There were 13 males and 5 females, with an average age of 43.2 years (range,19-56 years). Fractures were caused by traffic accident in 15 and by falling in 3. The fracture lines of 13 cases were located below the fovea of the femoral head and 5 cases were located above the fovea. According to Letournel-Judet classification for acetabular fractures, there were 14 cases of posterior acetabular wall fractures, 2 cases of posterior wall fractures involving posterior column, and 2 transverse plus posterior wall fractures. The operation was performed through DAA approach to treat the femoral head fractures, and DPA approach was used to treat acetabular fractures. Radiographs and CT scans of the pelvis were reexamined after surgery, and fracture reduction, healing, and complications such as femoral head necrosis, sciatic nerve injury, superior gluteal neurovascular injury and heterotopic ossification were evaluated. Quality of acetabular reduction was evaluated according to the criteria proposed by Matta. Thompson-Epstein scoring system was used to evaluate hip function.Results:The average operation time was 133 min (range, 75-205 min). And the average blood loss was 371 ml (range, 240-600 ml). All 18 patients were followed up for 6 to 36 months, with an average period of 15.7 months. All fractures healed 10 to14 weeks after surgery. Three patients had symptoms of sciatic nerve injury after the injury, who recovered 6 to 12 weeks after the operation. All femoral head fractures were reduced. According to Matta criteria of reduction quality, anatomic reduction was gained in 13 cases, and satisfactory reduction was obtained in 3 cases, while unsatisfactory reduction was found in 2 cases, and the overall satisfactory rate was 88.9%(16/18). Two patients had Brooker I level heterotopic ossification. There was no iatrogenic vascular injury, avascular necrosis of femoral head, infection, internal fixation failure or other complications. According to the Thompson-Epstein scoring system at the latest follow-up, the functional results of the affected hip were excellent in 7 cases, good in 8, fair in 2 and poor in 1.Conclusion:Treatment of Pipkin IV fractures through DAA combined with DPA approach reduces surgical invasion. And it can directly reduce and fix the femoral head and posterior acetabular fracture, and protect the important structures such as the arteriae circumflexa femoris medialis, sciatic nerve and lateral femoral cutaneous nerve, and reduce the occurrence of complications such as femoral head necrosis and heterotopic ossification. Therefore, DAA combined with DPA is aneffective method for the treatment of Pipkin IV fractures.