BACKGROUND:Platelet-rich fibrin(PRF)has many advantages,such as simple preparation,low production cost,and high safety,and has been widely used in the study of bone defect repair in oral and maxillofacial surgery,but there are problems such as too fast degradation rate and short release time of growth factors. OBJECTIVE:PRF was loaded into gelatin methacryloyl(GelMA)hydrogel and its osteogenic properties were analyzed by in vivo and in vitro experiments. METHODS:(1)New Zealand white rabbit venous blood was extracted to prepare PRF.GelMA hydrogels containing 0,0.05,0.075,and 0.1 g PRF were prepared,respectively,and were recorded as GelMA,GelMA/PRF-0.05,GelMA/PRF-0.075,and GelMA/PRF-0.1,respectively,to characterize the micromorphology and in vitro slow-release properties of the hydrogels.(2)Four kinds of hydrogels were co-cultured with MC3T3-E1 cells,respectively,and the cell proliferation activity was detected with the single cultured cells as the control.After osteogenic induction,alkaline phosphatase activity,mineralization ability,mRNA and protein expression levels of osteogenic genes(osteocalcin,osteopontin,RUNX2),ERK1/2-p38 MAPK pathway protein mRNA and protein expression levels were detected.(3)Fifteen New Zealand white rabbits were taken.Four full-layer bone defects of 8 mm diameter were prepared in the skull of each rabbit,one of which was implanted without any material(blank control group),and the other three were implanted with GelMA hydrogel,PRF,and GelMA/PRF-0.1 hydrogel,respectively.The bone defect was detected by Micro-CT and bone morphology was observed at 4,8,and 12 weeks after operation. RESULTS AND CONCLUSION:(1)Scanning electron microscopy observed that all the hydrogels of the four groups had honeycomb pore structure,and the pore size of the hydrogels decreased slightly with the increase of PRF content,but there was no significant difference between the groups.The three groups of GelMA/PRF hydrogel could release transforming growth factor β1 and insulin-like growth factor 1 at a certain rate,and the cumulative release of transforming growth factor β1 and insulin-like growth factor 1 increased significantly with the extension of time.(2)CCK-8 assay and live/dead staining showed that GelMA/PRF hydrogel could promote the proliferation of MC3T3-E1 cells.The results of alkaline phosphatase staining,alizarin red staining,and osteogenic gene detection showed that GelMA/PRF hydrogel could promote the osteogenic differentiation of MC3T3-E1 cells,and inhibit the expression of ERK1/2-p38 MAPK pathway protein,and showed a PRF content dependence.(3)Micro-CT scan showed that the bone mineral density and bone volume fraction in the bone defect of GelMA/PRF-0.1 hydrogel group were higher than those in the other three groups(P<0.05).Hematoxylin-eosin staining showed that compared with the other three groups,GelMA/PRF-0.1 hydrogel group had faster and more mature new bone formation at the bone defect.(4)These findings indicate that GelMA/PRF hydrogel has good osteogenic activity both in vivo and in vitro,which may be related to inhibiting the expression of ERK1/2-p38 MAPK pathway protein.

Objective To develop an unmanned aerial vehicle (UAV)-borne radiation monitoring system with high detection efficiency and nuclide identification ability for airborne monitoring in nuclear emergency. Methods The UAV-borne CeBr₃ radiation monitoring system was composed of four cerium bromide (CeBr₃) crystal detectors coupled with silicon photomultipliers (SiPMs) and other components including integrated modules, intelligent electronic devices, and new composite materials. Results According to various performance tests on the system, the crystal energy resolution was better than 5% (@0.662 MeV), the peak drift of the energy spectrum was within ±1 channel, the linear fit of energy was 0.99997, the change in the count rate of each energy window during 12 h long-term measurement was less than 5%, and the detection efficiency was higher compared with that of NaI (Tl) detectors of the same volume. Conclusion Through ground point source testing and theoretical calculation, the system has reliable ability to identify radionuclides, which can be used in nuclide identification and the preparedness and response for nuclear and radiation emergencies.

ObjectiveTo quantitatively investigate the changes in the total volume and contour density of hepatic oval cells （HOC） in hepatic lobules of rats with carbon tetrachloride （CCl₄）-induced hepatic fibrosis. MethodsA total of 11 healthy male Sprague-Dawley rats were randomly divided into control group with 5 rats and hepatic fibrosis group with 6 rats， and CCl₄ and olive oil suspension were injected subcutaneously twice a week， 3 mL/kg each time. After five weeks of hepatic fibrosis modeling， five liver tissue blocks with a size of about 1 mm³ were randomly selected from the liver of each rat to prepare one Epon812 epoxy resin-embedded ultrathin section， and the stereological method and transmission electron microscopy were used for the quantitative analysis of the total volume and contour density of HOC in the hepatic lobules of rats. In addition， four liver tissue blocks with a thickness of 2 mm were randomly selected from the remaining liver of each rat to prepare two paraffin-embedded Masson staining sections， and the degree of liver fibrosis in each rat was qualitatively evaluated according to the Metavir staging criteria for liver fibrosis. The independent-samples t test was used for comparison of continuous data between groups. ResultsThe quantitative stereological analysis showed that the total volume of HOC in hepatic lobules was 15.40±7.63 mm³ in the control group and 146.80±114.00 mm³ in the liver fibrosis group， and compared with the control group， the total volume of HOC in hepatic lobules of rats in the liver fibrosis group was significantly increased by 8.53 times （t=-2.551， P=0.031）； the contour density of HOC in hepatic lobules was 56.20±40.40 in the control group and 566.50±317.00 in the liver fibrosis group， and compared with the control group， the contour density of HOC in hepatic lobules of rats in the liver fibrosis group was significantly increased by 9.08 times （t=-3.539， P=0.006）. Qualitative observation showed that liver fibrosis stage of rats reached stage Ⅱ-Ⅲ according to the Metavir scoring criteria， and massive proliferation of HOC was observed around the proliferation site of hepatic stellate cells in the perisinusoidal space of rats. ConclusionCCl₄ induces significant proliferation of HOC in hepatic lobules of rats with liver fibrosis.

Objective:To evaluate the guiding value of ultrasound-guided selective nerve root block in the surgical treatment of multilevel lumbar degeneration.Methods:Retrospective case-control study was used. Clinical data of 47 patients with multi-level lumbar degeneration who underwent decompression surgery in Honghui Hospital, Xi′an Jiaotong University from January 2019 to December 2021 were retrospectively analyzed. They were divided into nerve root block group ( n=22)and non-nerve root block group( n=25) according to whether ultrasound-guided selective nerve root block was performed before decompression surgery. The operation time, intraoperative blood loss, number of decompression laminae, postoperative drainage volume and length of stay of the two groups were recorded and compared. The visual analogue scale of low back pain, the visual analogue scale (VAS) of leg pain, the Japanese orthopaedic association (JOA) score and Oswestry disability index (ODI) score were all compared before surgery and during follow-up between the two groups. Measurement data with normal distribution were represented as mean±standard deviation( ± s), and the comparison between groups was conducted using the paired t-test. Chi-square test was used for counting data. Results:All 47 patients successfully completed the operation without any serious complications such as neurovascular injury. All patients were followed up for (27.6±7.5)months. In the nerve root block group, the operation time, intraoperative blood loss, number of decompression laminae, postoperative drainage volume and hospital stay were (90.5±12.6) min, (110.5±15.8) mL, 1.2±0.8, (85.6±15.8) mL, (6.2±2.8) d, respectively. In the non-root block group, they were (190.6±25.5) min, (450.5±24.8) mL, 3.8±1.6, (210.5±16.8) mL, (9.5±2.2) d, respectively. The above indexes in the nerve root closure group were less than those in the non-root closure group, and the difference was significant between the two groups ( P< 0.05). The scores of VAS of low back pain and leg pain, JOA and ODI in both groups were significantly improved after surgery and during the follow-up period when compared with those of pre-operation ( P< 0.05). The VAS scores of low back pain on the 3rd day, 6 months after operation and at the last follow-up in the nerve block group were 3.2±1.4, 1.4±0.8, 0.5±0.2, the JOA scores were 15.8±4.3, 21.3±5.6, 25.6±1.4, and the ODI scores were 50.6±10.3, 22.8±7.8, 16.8±4.2, respectively. The VAS scores of low back pain on the 3rd day, 6 months after operation and at the last follow-up in the non-nerve block group were 5.1±1.8, 3.4±1.2, 1.8±0.5, the JOA scores were 14.1±4.8, 20.5±3.2, 24.2±1.8, and the ODI scores were 60.5±9.8, 31.6±8.2 and 21.3±5.5, respectively. The difference between the two groups was statistically significant ( P<0.05). However, there was no statistical difference in the VAS scores of leg pain between the two groups after surgery and during follow-up ( P>0.05). At the last follow-up, the internal fixation position of the two groups was good, no loosening and displacement, and bone graft fusion was good. Conclusion:For patients with multi-level lumbar degeneration, ultrasound-guided selective nerve root block before surgery can identify the responsible segment, and selective decompression and fusion based on this can effectively reduce surgical trauma, while improving patients′ back and leg pain and physical function, which has important surgical guidance value.

Hepato-pancreato-biliary diseases (HPBD) are often complicated. The diagnosis and treatment of HPBD involve many disciplines. The malignant degree of hepatobiliary pancreatic system is high, and the prognosis of patients is poor. The multidisciplinary team (MDT) brings specialists from different disciplines together to make a comprehensive and individualized treatment for patients. MDT is emerging in HPBD in recent years. MDT helps improve the accuracy of diagnosis and prognosis. However, there are still some controversies and obstacles in the application of MDT for patients with HPBD. We reviewed the development, current status and experience of MDT in the field of HPBD, analyze the current controversy and obstacles, and providing reference for its future application.

Endodontic diseases are a kind of chronic infectious oral disease.Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha.However,it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT).Recent research,encompassing bacterial etiology and advanced imaging techniques,contributes to our understanding of the root canal system's anatomy intricacies and the technique sensitivity of RCT.Success in RCT hinges on factors like patients,infection severity,root canal anatomy,and treatment techniques.Therefore,improving disease management is a key issue to combat endodontic diseases and cure periapical lesions.The clinical difficulty assessment system of RCT is established based on patient conditions,tooth conditions,root canal configuration,and root canal needing retreatment,and emphasizes pre-treatment risk assessment for optimal outcomes.The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT.These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics.

Objective To investigate the effect of minocycline(Mino)on the polarization of types M1/M2 microglia(pro-and anti-inflammatory type)in the spinal dorsal horn of rats with neuropathic pain(NP)induced by spinal nerve ligation(SNL)and its underlying mechanism.Methods A total of 36 adult male SD rats were randomly stratified into Sham-operation(Sham)group,SNL group and Mino+SNL group by stratified random sampling based on body weight.Mechanical pain threshold and cold nociceptive thresholds of rat hind paw were measured in 1 d before and 14 d after modelling.Spinal cord tissue at the lumbar 5(L5)segment was taken at 14 d after modelling,and the total number of microglia as well as the numbers of M1 and M2 microglia in the spinal dorsal horn were measured with immunohistochemistry and stereology.With aid of bioinformatics techniques,the core target in the spinal cord,Cst7,was selected.Then,the protein levels of microglia marker Iba-1,M1 microglia marker iNOS,M2 microglia marker CD206,Cst7 encoded protein cystatin F(CF)and pathway CatS/CX3CL1/CX3CR1 were detected with Western blotting.The expression levels of TNF-α,IL-6 and IL-10 in the spinal cord tissues were measured with ELISA.Results The mechanical pain and cold nociceptive thresholds were both significantly higher in the M+SNL group than the SNL group at 7～14 d after modelling(P＜0.01).The total number of microglia and the numbers of M1/M2 microglia in the spinal dorsal horn as well as the expression levels of CatS,CX3CL1,CX3CR1,TNF-α,IL-6,and IL-10 in the spinal cord tissues were obviously increased,and the expression level of CF was notably decreased in the SNL model group than the Sham group(P＜0.01).While,Mino treatment remarkably reversed above phenomena,with decreased total number of microglia and number of M1 microglia as well as expression levels of CatS,CX3CL1,CX3CR1,TNF-α and IL-6,and increased number of M2 microglia as well as CF and IL-10 levels when compared with the SNL group(P＜0.05).Conclusion Mino alleviates SNL induced neuropathic pain,probably through up-regulating CF in the microglia,and thus inhibiting the CatS/CX3CL1/CX3CR1 signaling pathway,promoting the conversion of microglia from type M1 to M2 to balance the imbalance in the M1/M2 polarization,and thus reducing neuroinflammation.

Purpose To investigate the characteristics of 18F-Florbetaben(18F-FBB)β-amyloid(Aβ)PET imaging in different brain regions of Alzheimer's disease(AD)patients with different degrees of cognitive impairment,and to explore the correlation between Aβ deposition and cognitive dysfunction.Materials and Methods A total of eighteen patients with a clinical diagnosis of probable AD from August 2022 to October 2023 were retrospectively included in Huashan Hospital.All patients had Aβ abnormal deposition in the brain as confirmed by 18F-FBB PET imaging.According to the severity of symptoms,they were divided into the AD-induced mild cognitive impairment(MCI)group(8 cases)and the dementia group(10 cases).In addition,12 healthy controls were included.First,the standardized uptake value ratio of abnormal Aβ deposition in the frontal lobe,lateral parietal lobe,lateral temporal lobe,anterior and posterior cingulate gyrus,and compound cortex was semi-quantitatively calculated and compared among the three groups based on the subjects'brain MRI and automated anatomical labeling template.The correlation between the degree of Aβ deposition in the brains of AD patients and cognitive scale scores(mini-mental state examination,Montreal cognitive assessment)was then further analyzed.Results The standardized uptake value ratio values of Aβabnormal deposition in the frontal lobe,lateral temporal lobe,lateral parietal lobe,anterior and posterior cingulate cortex and compound cortex in the AD-induced MCI and dementia groups were significantly higher than those in the healthy controls(t=7.442-9.151,all P＜0.05).However,there was no significant difference in the standardized uptake value ratio values of Aβ abnormal deposition in the above brain regions between the MCI and dementia groups(t=0.312-0.996,all P＞0.05).In addition,there was no significant correlation between the degree of Aβ deposition in the brain and the cognitive scale scores(mini-mental state examination,Montreal cognitive assessment)in the AD-induced MCI and dementia groups(r=-0.049-0.050,all P＞0.05).Conclusion Aβ deposition in the brains of AD-induced MCI and dementia is significantly higher than in the healthy controls.However,Aβ deposition cannot identify AD patients with different degrees of cognitive impairment,reflecting that Aβ deposition has certain limitations in assessing the severity of clinical symptoms of AD.

Objective:To explore the efficacy of secondary targeted percutaneous vertebroplasty (PVP) for the treatment of refracture of injured vertebrae after vertebral augmentation for osteoporotic vertebral compression fracture (OVCF).Methods:A retrospective case series study was performed on the clinical data of 25 patients with refracture of injured vertebrae after vertebral augmentation for OVCF admitted to Honghui Hospital, Xi′an Jiaotong University from January 2019 to January 2022, including 10 males and 15 females, aged 62-86 years [(73.8±5.2)years]. The fractured segments involved T 10 in 1 patient, T 11 in 2, T 12 in 10, L 1 in 10 and L 2 in 2. All the patients were treated with secondary targeted PVP. The operation time and the amount of bone cement injected were recorded. The visual analogue scale (VAS) of lower back, Oswestry disability index (ODI), vertebral body index (VBI) and kyphotic angle (KA) were compared before surgery, at 1 day, 6 months after surgery and at the last follow-up. Odom criteria were used to evaluate the efficacy of the surgical procedure at the last follow-up. The intraoperative bone cement leakage and new vertebrae fracture during follow-up were observed. Results:All the patients were followed up for 23-59 months [(36.8±7.6)months]. The operation time was 35-60 minutes [(42.6±5.2)minutes], with the amount of bone cement injected for 3-5 ml [(3.6±0.8)ml]. The VAS scores of lower back at 1 day, 6 months after surgery and at the last follow-up were 3.1(2.0, 4.0)points, 1.7(1.0, 2.0)points and 0.6(0.0, 1.0)points respectively, significantly lower than 7.6(7.0, 9.0)points before surgery ( P<0.01), and a statistically singnificant decrease was found over follow-up time ( P<0.01). The ODI values at 1 day, 6 months after surgery and at the last follow-up were (49.5±5.9)%, (28.5±4.6)% and (19.2±4.8)% respectively, significantly lower than (78.8±6.8)% before surgery ( P<0.01), and a statistically singnificant decrease was found over follow-up time ( P<0.01). The VBI values at 1 day, 6 months after surgery and at the last follow-up were (76.6±4.5)%, (76.3±4.0)% and (76.1±3.8)% respectively, significantly higher than (58.9±5.8)% before surgery ( P<0.01), while there were no significant differences among those at 1 day, 6 months after surgery and at the last follow-up ( P>0.05). The KA values at 1 day, 6 months after surgery and at the last follow-up were (12.4±2.7)°, (12.6±2.5)° and (12.8±2.9)° respectively, significantly lower than (20.8±3.6)° before surgery ( P<0.01), while there were no significant differences among those at 1 day, 6 months after surgery and at the last follow-up ( P>0.05). According to the Odom criteria, 20 patients were rated excellent and 5 good at the last follow-up, with an excellent and good rate of 100%. Intraoperative asymptomatic bone cement leakage occurred in 3 patients (12%), including 2 with intervertebral leakage and 1 with lateral vertebral leakage. No adjacent vertebral body or other vertebral fracture was observed during the follow-up. Conclusions:For patients with refracture of injured vertebrae after vertebral augmentation for OVCF, the secondary targeted PVP has advantages of attenuation of the lower back pain, improvement of the quality of life, restoration of the height of refractured vertebrae, correction of the local kyphosis, and a low incidence of complications.

With widespread popularization, the radiological diagnosis and treatment technology has played an increasingly important role in clinical practice. The tertiary general hospital is generally featured as multiple types of radioisotope and radiation equipment, wide involvement of departments and persons, and many ways of use and potential harms of the radiological diagnosis and treatment technology. Radiation protection has become a content that cannot be ignored in hospital management. This article analyzes the radiation protection management structure of the tertiary general hospital - Guangdong Provincial People’s Hospital. The hospital radiation protection management is gradually improved by clarifying the main leading department, refining duties and responsibilities, strengthening multi-departmental communication and cooperation, and sorting out key connection links. A closed loop of refined management is formed through digging and correcting problems and continuously improving the management level and work efficiency. Valid qualifications are ensured to be obtained in time by radiation workers, radioactive drugs, equipment, and the venues to guarantee the radiation safety of radiation workers and patients and to further promote the construction of the Safe Hospital.