Objective:To study and design one kind of flash radiotherapy(Flash-RT)equipment with ultra-high dose rate,which can be used in the mechanism research of Flash-RT with ultra-high dose rate.Methods:Based on the technique roadmap of high-power petal accelerator,the Flash-RT equipment can realize the requirement of Flash-RT for ultra-high dose rate and multiple irradiation angles.The corresponding design and research work were carried out on the basis of the overall design of the equipment,the main components and characteristics,the dynamics design of beam,the construction of movable and preliminary experimental platform,etc.Result:The dose rate of the designed equipment can reach to 100 Gy/s at a distance of 0.8 meters from the target point,which is easy to realize the radiotherapy method with multi angles.Conclusion:The designed X-ray equipment based on the technique roadmap of high-power petal accelerator can realize the research for the mechanism of medical Flash-RT equipment with ultra-high dose rate.

The protection effect of flash-radiotherapy(Flash-RT)with super-high dose on normal tissue has obtained wide attention in therapeutic radiology since it was found in 2014 year.The increasing research demand of Flash-RT with super-high dose-rate proposed new challenge for the existing radiotherapy equipment.Based on the demands of FLASH-RT research and clinical application,this review analyzed the proposed new requirement of Flash-RT for equipment,and introduce current scientific facilities with the experimental ability of X-ray FLASH-RT,as well as the situation of the specialized FLASH-RT equipment which were developing.The research of Flash-RT mechanism need the existing equipment with high-energy X-ray source develop toward high power,while the clinical application of Flash-RT demand these transient high-power devices should possess a series of radiotherapy techniques such as multi angle irradiation,conformal radiotherapy and others.Currently,China's X-ray FLASH-RT research is at the forefront of the world,which is expected to achieve the first breakthrough of high-end medical equipment in the X-ray Flash RT field.

BACKGROUND:Pauwels Ⅲ femoral neck fracture is a typical unstable fracture characterized by high vertical shear force and high incidence of postoperative complications.At present,there are many fixation methods for Pauwels Ⅲ fracture,and there is no clear conclusion as to which internal fixation is the best fixation method for Pauwels Ⅲ femoral neck fracture in young adults. OBJECTIVE:To compare the clinical effect of three inverted triangle cannulated screws assisted transverse lag screws and femoral neck system in fixing Pauwels Ⅲ femoral neck fractures of young adults. METHODS:From May 2021 to December 2022,21 young and middle-aged patients with Pauwels Ⅲ femoral neck fracture were treated with three inverted triangle cannulated screws assisted by transverse lag screws and femoral neck system in Affiliated Hospital of Southwest Medical University.Of them,9 patients were treated with three inverted triangle cannulated screws and one transverse lag screws perpendicular to the fracture line as the 3+1 cannulated screw group and 12 patients were treated with femoral neck system as the femoral neck system group.The two fixation methods were compared in terms of operation time,intraoperative blood loss,total incision length,intraoperative fluoroscopy times,fracture healing time,and limb function. RESULTS AND CONCLUSION:(1)All patients were followed up.Patients in the 3+1 cannulated screw group were followed up for 10-25 months,with a mean of(17.44±4.30)months.The patients in the femoral neck system group were followed up for 8-24 months,with a mean of(15.58±4.68)months.(2)The intraoperative fluoroscopy times and Harris score at 3 months postoperatively in the femoral neck system group were better than those in the 3+1 cannulated screw group,and the difference was statistically significant(P<0.05).The intraoperative blood loss,total incision length,and femoral neck shortening distance in the 3+1 cannulated screw group were better than those in the femoral neck system group,and the differences were statistically significant(P<0.05).There was no significant difference in operation time,fracture healing time,and Harris score at the last follow-up between the two groups(P>0.05).(3)It is indicated that three inverted triangle cannulated screws assisted transverse lag screw and femoral neck system can achieve good clinical effects in the treatment of young and middle-aged Pauwels Ⅲ femoral neck fracture.The femoral neck system has fewer intraoperative fluoroscopy times and better early overall stability,while the 3+1 cannulated screw is more minimally invasive,easier to operate.Both fixation methods are worthy of clinical application and promotion,and can be selected according to the actual clinical situation.

Octapeptin has strong antibacterial activity against Gram-negative bacteria such as Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii, while it also has activity against some Gram-positive bacteria. This study used natural octapeptin A3 and B3 as lead compounds for structural modification. Twenty-one peptide derivatives (including A3 and B3) containing eight amino acid residues were prepared by solid-phase synthesis, and evaluated for antibacterial activity and renal cytotoxicity. Among them, three compounds 6, 7 and 17 exhibited broad-spectrum antibacterial activity and significantly enhanced the activity for Gram-positive bacteria while maintaining the activity of Gram-negative bacteria. Several compounds improved the activity for Pseudomonas aeruginosa. Compound 7 was active against all test strains and had relatively low renal cytotoxicity. The results provide a basis for the further development of novel polypeptide antibiotics.

Bone Transplantation/adverse effects* ; Transplantation, Autologous/adverse effects*

OBJECTIVE To establish fingerprints and multi-components determination of Jieze lotion, and use chemometrics methods for quality evaluation. METHODS The HPLC-DAD fingerprints was established and 10 components were recognized by comparison with references. Meanwhile, their contents were determined. The data were evaluated by the methods of chemometrics such as similarity evaluation, cluster analysis, principal component analysis, and orthogonal partial least squares-discriminant analysis. RESULTS The similarity of 11 batches of Jieze lotion were all >0.95. The linearity was good(r≥0. 999 1) and the average recoveries were between 89.70% and 106.0% with the RSD of 1.52%−3.41%. Instrument precision, stability and reproducibility of the method were all great. The contents of the common ten components(gallic acid, protocatechuic acid, neochlorogenic acid, caftaricacid, 5-O-feruloylquinicacid, chlorogenic acid, phellodendrine chloride, magnoflorine, 4-O-feruloylquinic acid, berberinehydrochloride) were 40.103−55.841, 2.347−6.179, 8.336−23.810, 7.084−21.956, 33.098−53.833, 24.597−49.610, 21.587−31.188, 5.915−13.162, 115.381−189.702, 31.378−112.686 μg·mL−1, respectively. The results of chemometrics showed that the 11 batches of samples could be divided into 4 categories, and the strong characteristic peaks used to distinguish each batch of samples were berberine hydrochloride, 4-O-feruloylquinic acid, chlorogenic acid, neochlorogenic acid and 5-O-feruloylquinic acid. CONCLUSION The method is accurate and reliable, and it can be used for the quality control and comprehensive evaluation of Jieze lotion.

177Lu-prostate specific membrane antigen(PSMA)radio-ligand therapy has been approved abroad for advanced prostate cancer and has been in several clinical trials in China.Based on domestic clinical practice and experimental data and referred to international experience and viewpoints,the expert group forms a consensus on the clinical application of 177Lu-PSMA radio-ligand therapy in prostate cancer to guide clinical practice.

Background::Few evidence is available in the early prediction models of behavioral and psychological symptoms of dementia (BPSD) in Alzheimer’s disease (AD). This study aimed to develop and validate a novel genetic-clinical-radiological nomogram for evaluating BPSD in patients with AD and explore its underlying nutritional mechanism.Methods::This retrospective study included 165 patients with AD from the Chinese Imaging, Biomarkers, and Lifestyle (CIBL) cohort between June 1, 2021, and March 31, 2022. Data on demographics, neuropsychological assessments, single-nucleotide polymorphisms of AD risk genes, and regional brain volumes were collected. A multivariate logistic regression model identified BPSD-associated factors, for subsequently constructing a diagnostic nomogram. This nomogram was internally validated through 1000-bootstrap resampling and externally validated using a time-series split based on the CIBL cohort data between June 1, 2022, and February 1, 2023. Area under receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were used to assess the discrimination, calibration, and clinical applicability of the nomogram.Results::Factors independently associated with BPSD were: CETP rs1800775 (odds ratio [OR] = 4.137, 95% confidence interval [CI]: 1.276-13.415, P = 0.018), decreased Mini Nutritional Assessment score (OR = 0.187, 95% CI: 0.086-0.405, P <0.001), increased caregiver burden inventory score (OR = 8.993, 95% CI: 3.830-21.119, P <0.001), and decreased brain stem volume (OR = 0.006, 95% CI: 0.001-0.191, P = 0.004). These variables were incorporated into the nomogram. The area under the ROC curve was 0.925 (95% CI: 0.884-0.967, P <0.001) in the internal validation and 0.791 (95% CI: 0.686-0.895, P <0.001) in the external validation. The calibration plots showed favorable consistency between the prediction of nomogram and actual observations, and the DCA showed that the model was clinically useful in both validations. Conclusion::A novel nomogram was established and validated based on lipid metabolism-related genes, nutritional status, and brain stem volumes, which may allow patients with AD to benefit from early triage and more intensive monitoring of BPSD.Registration::Chictr.org.cn, ChiCTR2100049131.

Objective To construct a big data sharing platform for clinical scientific research to solve the problems of clinical research in decentralized application systems and data sharing safety.Methods A clinical research information data usage management system was developed through the formulation of management methods in line with the actual situation of the institution,normalized standard data usage processes and a data usage service team.Then a clinical scientific research big data sharing platform including the components for sharing environment construction,research application integration,data desensitization and encryption and file management was established based on the existing hospital systems,the requirements of clinical research data usage management and the habits of clinical researchers.Results The platform realized the balance between open sharing of clinical research data and data security control,which improved the efficiency of clinical researchers while reducing data security risks during data transmission and data analysis.Conclusion The clinical scientific research big data sharing platform meets the needs of clinical scientific research application and data security management,and provides references for the co-construction-sharing of medical big data resources.[Chinese Medical Equipment Journal,2024,45(4):27-31]

Objective To compare the effects of transumbilical single-incision appendectomy and laparoscopic appendectomy in the treatment of acute appendicitis in pediatric patients.Methods The clinical data of 162 pediatric patients under 14 years old with acute appendicitis admitted to our department were retrospectively analyzed,and the pediatric patients were divided into the transumbilical single-incision surgery group(n=59)and the laparoscopic group(n=103)according to their surgeries.The completion of the operation was recorded,and the operation time,intraoperative blood loss,gastrointestinal function recovery time,hospitalization cost,hospital stay and complications were compared between the two groups.The postoperative wound healing was observed.The wound infection,abdominal pain,abdominal distension,vomiting and abnormal stool were observed during the 6-month follow-up after operation.Results The operations of pediatric patients in the laparoscopic group were successfully completed without conversion to open surgery.The appendixes of 2 cases in the transumbilical single-incision surgery group were found by transumbilical laparoscopy during the operation due to the difficulty in finding the appendixes.The operation time and hospital stay in the transumbilical single-incision surgery group were shorter than those in the laparoscopic group(P<0.05).There was no significant difference in the hospitalization cost,intraoperative blood loss,gastrointestinal function recovery time,or incidence of complications between the two groups(P>0.05).The incision healing in the transumbilical single-incision surgery group was more beautiful.During the follow-up period,the incision of the pediatric patients in the two groups healed well,and there was no abdominal pain,abdominal distension,vomiting or abnormal stool.Conclusion Compared with the traditional laparoscopic appendectomy,transumbilical single-incision appendectomy has the advantages of simple operation,short operation time and hospital stay,and more beautiful incision healing.